Bump versions

Redstone behaviour tweaks

README.md

@@ -45,3 +45,22 @@ develop CC:T, you'll need to follow these steps:
  - **Test your changes:** `./gradlew runClient` (or run the `GradleStart` class from your IDE).
 
 If you want to run CC:T in a normal Minecraft instance, run `./gradlew build` and copy the `.jar` from `build/libs`.
+
+## Using
+If you want to depend on CC:Tweaked, we have a maven repo. However, you should be wary that some functionality is only
+exposed by CC:T's API and not vanilla ComputerCraft. If you wish to support all variations of ComputerCraft, I recommend
+using [cc.crzd.me's maven](https://cc.crzd.me/maven/) instead.
+
+```groovy
+dependencies {
+  maven { url 'https://squiddev.cc/maven/' }
+}
+
+dependencies {
+  implementation "org.squiddev:cc-tweaked-${mc_version}:${cct_version}"
+}
+```
+
+You should also be careful to only use classes within the `dan200.computercraft.api` package. Non-API classes are
+subject to change at any point. If you depend on functionality outside the API, file an issue, and we can look into
+exposing more features.

build.gradle

@@ -1,8 +1,7 @@
-
-// For those who want the bleeding edge
 buildscript {
     repositories {
         jcenter()
+        mavenCentral()
         maven {
             name = "forge"
             url = "http://files.minecraftforge.net/maven"
@@ -10,53 +9,76 @@ buildscript {
     }
     dependencies {
         classpath 'com.google.code.gson:gson:2.8.1'
-        classpath 'net.minecraftforge.gradle:ForgeGradle:2.3-SNAPSHOT'
+        classpath 'net.minecraftforge.gradle:ForgeGradle:3.0.117'
-        classpath 'net.sf.proguard:proguard-gradle:6.1.0beta1'
+        classpath 'net.sf.proguard:proguard-gradle:6.1.0beta2'
         classpath 'org.ajoberstar.grgit:grgit-gradle:3.0.0'
     }
 }
 
 plugins {
-    id 'com.matthewprenger.cursegradle' version '1.0.10'
+    id 'com.matthewprenger.cursegradle' version '1.2.0'
+    id "com.github.breadmoirai.github-release" version "2.2.4"
 }
 
-apply plugin: 'net.minecraftforge.gradle.forge'
+apply plugin: 'net.minecraftforge.gradle'
 apply plugin: 'org.ajoberstar.grgit'
 apply plugin: 'maven-publish'
 apply plugin: 'maven'
 
-def mc_version = "1.12.2"
+version = mod_version
-def main_version = "1.81.1"
-version = "${mc_version}-${main_version}"
 
 group = "org.squiddev"
-archivesBaseName = "cc-tweaked"
+archivesBaseName = "cc-tweaked-${mc_version}"
 
 minecraft {
-    version = "${mc_version}-14.23.4.2749"
+    runs {
-    runDir = "run"
+        client {
-    replace '${version}', main_version
+            workingDirectory project.file('run')
+            property 'forge.logging.markers', 'REGISTRIES'
+            property 'forge.logging.console.level', 'debug'
 
-    // the mappings can be changed at any time, and must be in the following format.
+            mods {
-    // snapshot_YYYYMMDD   snapshot are built nightly.
+                computercraft {
-    // stable_#            stables are built at the discretion of the MCP team.
+                    source sourceSets.main
-    // Use non-default mappings at your own risk. they may not allways work.
+                }
-    // simply re-run your setup task after changing the mappings to update your workspace.
+            }
-    mappings = "snapshot_20180724"
+        }
-    // makeObfSourceJar = false // an Srg named sources jar is made by default. uncomment this to disable.
+
+        server {
+            workingDirectory project.file('run')
+            property 'forge.logging.markers', 'SCAN,REGISTRIES,REGISTRYDUMP'
+            property 'forge.logging.console.level', 'debug'
+
+            mods {
+                computercraft {
+                    source sourceSets.main
+                }
+            }
+        }
+    }
+
+    mappings channel: 'snapshot', version: "${mappings_version}".toString()
+
+    accessTransformer file('src/main/resources/META-INF/accesstransformer.cfg')
 }
 
 repositories {
     maven {
-        name = "JEI"
+        name "JEI"
-        url  = "http://dvs1.progwml6.com/files/maven"
+        url  "http://dvs1.progwml6.com/files/maven"
     }
     maven {
-        name = "squiddev"
+        name "SquidDev"
-        url = "https://squiddev.cc/maven"
+        url "https://squiddev.cc/maven"
+    }
+    ivy {
+        name "Charset"
+        artifactPattern "https://asie.pl/files/mods/Charset/LibOnly/[module]-[revision](-[classifier]).[ext]"
+    }
+    maven {
+        name "Amadornes"
+        url "http://maven.amadornes.com/"
     }
-
-    ivy { artifactPattern "https://asie.pl/files/mods/Charset/LibOnly/[module]-[revision](-[classifier]).[ext]" }
 }
 
 configurations {
@@ -66,18 +88,31 @@ configurations {
 }
 
 dependencies {
-    deobfProvided "mezz.jei:jei_1.12.2:4.8.5.159:api"
+    minecraft "net.minecraftforge:forge:${mc_version}-${forge_version}"
-    deobfProvided "pl.asie:Charset-Lib:0.5.4.6"
 
-    runtime "mezz.jei:jei_1.12.2:4.8.5.159"
+    compileOnly fg.deobf("mezz.jei:jei-1.13.2:5.0.0.20:api")
+    // deobfProvided "pl.asie:Charset-Lib:0.5.4.6"
+    // deobfProvided "MCMultiPart2:MCMultiPart:2.5.3"
+
+    runtimeOnly fg.deobf("mezz.jei:jei-1.13.2:5.0.0.20")
 
     shade 'org.squiddev:Cobalt:0.5.0-SNAPSHOT'
 
-    testCompile 'junit:junit:4.11'
+    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.1.0'
+    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.1.0'
 
     deployerJars "org.apache.maven.wagon:wagon-ssh:3.0.0"
 }
 
+sourceSets {
+    main {
+        java {
+            exclude 'dan200/computercraft/shared/integration/mcmp'
+            exclude 'dan200/computercraft/shared/integration/charset'
+        }
+    }
+}
+
 javadoc {
     include "dan200/computercraft/api/**/*.java"
 }
@@ -86,7 +121,13 @@ jar {
     dependsOn javadoc
 
     manifest {
-        attributes('FMLAT': 'computercraft_at.cfg')
+        attributes(["Specification-Title": "computercraft",
+                    "Specification-Vendor": "SquidDev",
+                    "Specification-Version": "25.0",
+                    "Implementation-Title": "CC: Tweaked",
+                    "Implementation-Version": "${mod_version}",
+                    "Implementation-Vendor" :"SquidDev",
+                    "Implementation-Timestamp": new Date().format("yyyy-MM-dd'T'HH:mm:ssZ")])
     }
 
     from (sourceSets.main.allSource) {
@@ -131,6 +172,10 @@ task proguard(type: ProGuardTask, dependsOn: jar) {
 
     // Preserve the constructors in Cobalt library class, as we init them via reflection
     keepclassmembers 'class org.squiddev.cobalt.lib.** { <init>(...); }'
+
+    // LWJGL and Apache bundle Java 9 versions, which is great, but rather breaks Proguard
+    dontwarn 'module-info'
+    dontwarn 'org.apache.**,org.lwjgl.**'
 }
 
 task proguardMove(dependsOn: proguard) {
@@ -146,10 +191,10 @@ task proguardMove(dependsOn: proguard) {
     }
 }
 
-reobfJar.dependsOn proguardMove
+
 
 processResources {
-    inputs.property "version", main_version
+    inputs.property "version", mod_version
     inputs.property "mcversion", mc_version
 
     def hash = 'none'
@@ -168,21 +213,21 @@ processResources {
     inputs.property "commithash", hash
 
     from(sourceSets.main.resources.srcDirs) {
-        include 'mcmod.info'
+        include 'META-INF/mods.toml'
-        include 'assets/computercraft/lua/rom/help/credits.txt'
+        include 'data/computercraft/lua/rom/help/credits.txt'
 
-        expand 'version': main_version,
+        expand 'version': mod_version,
                'mcversion': mc_version,
                'gitcontributors': contributors.sort(false, String.CASE_INSENSITIVE_ORDER).join('\n')
     }
 
     from(sourceSets.main.resources.srcDirs) {
-        exclude 'mcmod.info'
+        exclude 'META-INF/mods.toml'
-        exclude 'assets/computercraft/lua/rom/help/credits.txt'
+        exclude 'data/computercraft/lua/rom/help/credits.txt'
     }
 }
 
-task compressJson(dependsOn: extractAnnotationsJar) {
+task compressJson(dependsOn: jar) {
     group "compact"
     description "Minifies all JSON files, stripping whitespace"
 
@@ -228,8 +273,8 @@ curseforge {
     apiKey = project.hasProperty('curseForgeApiKey') ? project.curseForgeApiKey : ''
     project {
         id = '282001'
-        releaseType = 'release'
+        releaseType = 'beta'
-        changelog = "Release notes can be found on the GitHub repository (https://github.com/SquidDev-CC/CC-Tweaked/releases/tag/v${project.version})."
+        changelog = "Release notes can be found on the GitHub repository (https://github.com/SquidDev-CC/CC-Tweaked/releases/tag/v${mc_version}-${mod_version})."
     }
 }
 
@@ -237,7 +282,7 @@ publishing {
     publications {
         mavenJava(MavenPublication) {
             from components.java
-            artifact sourceJar
+            // artifact sourceJar
         }
     }
 }
@@ -257,22 +302,22 @@ uploadArchives {
                 pom.project {
                     name 'CC: Tweaked'
                     packaging 'jar'
-                    description 'A fork of ComputerCraft which aims to provide earlier access to the more experimental and in-development features of the mod.'
+                    description 'CC: Tweaked is a fork of ComputerCraft, adding programmable computers, turtles and more to Minecraft.'
                     url 'https://github.com/SquidDev-CC/CC-Tweaked'
 
                     scm {
-                        url 'https://github.com/dan200/ComputerCraft.git'
+                        url 'https://github.com/SquidDev-CC/CC-Tweaked.git'
                     }
 
                     issueManagement {
                         system 'github'
-                        url 'https://github.com/dan200/ComputerCraft/issues'
+                        url 'https://github.com/SquidDev-CC/CC-Tweaked/issues'
                     }
 
                     licenses {
                         license {
                             name 'ComputerCraft Public License, Version 1.0'
-                            url 'https://github.com/dan200/ComputerCraft/blob/master/LICENSE'
+                            url 'https://github.com/SquidDev-CC/CC-Tweaked/blob/master/LICENSE'
                             distribution 'repo'
                         }
                     }
@@ -286,11 +331,37 @@ uploadArchives {
     }
 }
 
-gradle.projectsEvaluated {
+githubRelease {
-    tasks.withType(JavaCompile) {
+    token project.hasProperty('githubApiKey') ? project.githubApiKey : ''
-        options.compilerArgs << "-Xlint"
+    owner 'SquidDev-CC'
+    repo 'CC-Tweaked'
+    targetCommitish (mc_version == "1.12.2" ? "master" : mc_version)
+
+    tagName "v${mc_version}-${mod_version}"
+    releaseName "[${mc_version}] ${mod_version}"
+    body ''
+    prerelease true
+
+    releaseAssets.from(jar.archivePath)
+}
+
+task uploadAll(dependsOn: [uploadArchives, "curseforge", "githubRelease"]) {
+    group "upload"
+    description "Uploads to all repositories (Maven, Curse, GitHub release)"
+}
+
+test {
+    useJUnitPlatform()
+    testLogging {
+        events "passed", "skipped", "failed"
+    }
+}
+
+gradle.projectsEvaluated {
+    reobfJar.dependsOn proguardMove
+
+    tasks.withType(JavaCompile) {
+        options.compilerArgs << "-Xlint" << "-Xlint:-processing" // Causes Forge build to fail << "-Werror"
     }
 }
 
-runClient.outputs.upToDateWhen { false }
-runServer.outputs.upToDateWhen { false }

gradle.properties

@@ -0,0 +1,7 @@
+# Mod properties
+mod_version=1.82.3
+
+# Minecraft properties
+mc_version=1.13.2
+forge_version=25.0.175
+mappings_version=20190424-1.13.2

gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.9-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.3-bin.zip

settings.gradle

@@ -1 +1 @@
-rootProject.name = 'cc-tweaked'
+rootProject.name = "cc-tweaked-${mc_version}"

src/main/java/dan200/computercraft/ComputerCraft.java

@@ -7,115 +7,50 @@
 package dan200.computercraft;
 
 import dan200.computercraft.api.filesystem.IMount;
-import dan200.computercraft.api.filesystem.IWritableMount;
-import dan200.computercraft.api.lua.ILuaAPIFactory;
-import dan200.computercraft.api.media.IMedia;
-import dan200.computercraft.api.media.IMediaProvider;
-import dan200.computercraft.api.network.IPacketNetwork;
-import dan200.computercraft.api.network.wired.IWiredElement;
-import dan200.computercraft.api.network.wired.IWiredNode;
-import dan200.computercraft.api.peripheral.IPeripheral;
-import dan200.computercraft.api.peripheral.IPeripheralProvider;
-import dan200.computercraft.api.permissions.ITurtlePermissionProvider;
-import dan200.computercraft.api.pocket.IPocketUpgrade;
-import dan200.computercraft.api.redstone.IBundledRedstoneProvider;
-import dan200.computercraft.api.turtle.ITurtleUpgrade;
 import dan200.computercraft.api.turtle.event.TurtleAction;
 import dan200.computercraft.core.apis.AddressPredicate;
-import dan200.computercraft.core.apis.ApiFactories;
 import dan200.computercraft.core.apis.http.websocket.Websocket;
-import dan200.computercraft.core.filesystem.ComboMount;
+import dan200.computercraft.core.filesystem.ResourceMount;
-import dan200.computercraft.core.filesystem.FileMount;
+import dan200.computercraft.shared.Config;
-import dan200.computercraft.core.filesystem.JarMount;
-import dan200.computercraft.core.terminal.Terminal;
-import dan200.computercraft.core.tracking.Tracking;
-import dan200.computercraft.shared.*;
-import dan200.computercraft.shared.computer.blocks.BlockCommandComputer;
 import dan200.computercraft.shared.computer.blocks.BlockComputer;
-import dan200.computercraft.shared.computer.blocks.TileComputer;
 import dan200.computercraft.shared.computer.core.ClientComputerRegistry;
-import dan200.computercraft.shared.computer.core.ComputerFamily;
-import dan200.computercraft.shared.computer.core.ServerComputer;
 import dan200.computercraft.shared.computer.core.ServerComputerRegistry;
-import dan200.computercraft.shared.computer.items.ItemCommandComputer;
 import dan200.computercraft.shared.computer.items.ItemComputer;
-import dan200.computercraft.shared.media.items.ItemDiskExpanded;
+import dan200.computercraft.shared.media.items.ItemDisk;
-import dan200.computercraft.shared.media.items.ItemDiskLegacy;
 import dan200.computercraft.shared.media.items.ItemPrintout;
 import dan200.computercraft.shared.media.items.ItemTreasureDisk;
-import dan200.computercraft.shared.network.NetworkHandler;
+import dan200.computercraft.shared.peripheral.diskdrive.BlockDiskDrive;
-import dan200.computercraft.shared.peripheral.common.BlockPeripheral;
-import dan200.computercraft.shared.peripheral.common.ItemPeripheral;
-import dan200.computercraft.shared.peripheral.diskdrive.TileDiskDrive;
 import dan200.computercraft.shared.peripheral.modem.wired.BlockCable;
 import dan200.computercraft.shared.peripheral.modem.wired.BlockWiredModemFull;
-import dan200.computercraft.shared.peripheral.modem.wired.ItemCable;
+import dan200.computercraft.shared.peripheral.modem.wired.ItemBlockCable;
-import dan200.computercraft.shared.peripheral.modem.wireless.BlockAdvancedModem;
+import dan200.computercraft.shared.peripheral.modem.wireless.BlockWirelessModem;
-import dan200.computercraft.shared.peripheral.modem.wireless.ItemAdvancedModem;
+import dan200.computercraft.shared.peripheral.monitor.BlockMonitor;
-import dan200.computercraft.shared.peripheral.modem.wireless.WirelessNetwork;
+import dan200.computercraft.shared.peripheral.printer.BlockPrinter;
-import dan200.computercraft.shared.peripheral.printer.TilePrinter;
+import dan200.computercraft.shared.peripheral.speaker.BlockSpeaker;
 import dan200.computercraft.shared.pocket.items.ItemPocketComputer;
 import dan200.computercraft.shared.pocket.peripherals.PocketModem;
 import dan200.computercraft.shared.pocket.peripherals.PocketSpeaker;
-import dan200.computercraft.shared.proxy.ICCTurtleProxy;
-import dan200.computercraft.shared.proxy.IComputerCraftProxy;
 import dan200.computercraft.shared.turtle.blocks.BlockTurtle;
-import dan200.computercraft.shared.turtle.blocks.TileTurtle;
+import dan200.computercraft.shared.turtle.items.ItemTurtle;
-import dan200.computercraft.shared.turtle.items.ItemTurtleAdvanced;
-import dan200.computercraft.shared.turtle.items.ItemTurtleLegacy;
-import dan200.computercraft.shared.turtle.items.ItemTurtleNormal;
 import dan200.computercraft.shared.turtle.upgrades.*;
-import dan200.computercraft.shared.util.CreativeTabMain;
+import net.minecraft.resources.IReloadableResourceManager;
-import dan200.computercraft.shared.util.IDAssigner;
+import net.minecraft.util.ResourceLocation;
-import dan200.computercraft.shared.util.IoUtil;
-import dan200.computercraft.shared.wired.CapabilityWiredElement;
-import dan200.computercraft.shared.wired.WiredNode;
-import net.minecraft.entity.player.EntityPlayer;
-import net.minecraft.item.ItemBlock;
-import net.minecraft.item.ItemStack;
-import net.minecraft.server.MinecraftServer;
-import net.minecraft.tileentity.TileEntity;
-import net.minecraft.util.EnumFacing;
-import net.minecraft.util.EnumHand;
-import net.minecraft.util.math.BlockPos;
-import net.minecraft.world.IBlockAccess;
-import net.minecraft.world.World;
-import net.minecraftforge.common.DimensionManager;
-import net.minecraftforge.fml.common.FMLCommonHandler;
 import net.minecraftforge.fml.common.Mod;
-import net.minecraftforge.fml.common.SidedProxy;
+import net.minecraftforge.fml.server.ServerLifecycleHooks;
-import net.minecraftforge.fml.common.event.*;
+import org.apache.logging.log4j.LogManager;
-import net.minecraftforge.fml.relauncher.Side;
 import org.apache.logging.log4j.Logger;
 
-import java.io.*;
+import java.io.IOException;
-import java.net.MalformedURLException;
+import java.io.InputStream;
-import java.net.URISyntaxException;
-import java.net.URL;
-import java.util.ArrayList;
 import java.util.EnumSet;
-import java.util.List;
+import java.util.concurrent.TimeUnit;
-import java.util.zip.ZipEntry;
-import java.util.zip.ZipFile;
 
-@Mod(
+@Mod( ComputerCraft.MOD_ID )
-    modid = ComputerCraft.MOD_ID, name = "CC: Tweaked", version = "${version}",
+public final class ComputerCraft
-    guiFactory = "dan200.computercraft.client.gui.GuiConfigCC$Factory",
-    dependencies = "required:forge@[14.23.4.2746,)"
-)
-public class ComputerCraft
 {
     public static final String MOD_ID = "computercraft";
 
-    // GUI IDs
+    public static final int DATAFIXER_VERSION = 0;
-    public static final int diskDriveGUIID = 100;
-    public static final int computerGUIID = 101;
-    public static final int printerGUIID = 102;
-    public static final int turtleGUIID = 103;
-    // ComputerCraftEdu uses ID 104
-    public static final int printoutGUIID = 105;
-    public static final int pocketComputerGUIID = 106;
-    public static final int viewComputerGUIID = 110;
 
     // Configuration options
     public static final String[] DEFAULT_HTTP_WHITELIST = new String[] { "*" };
@@ -133,9 +68,12 @@ public class ComputerCraft
     public static boolean disable_lua51_features = false;
     public static String default_computer_settings = "";
     public static boolean debug_enable = true;
-    public static int computer_threads = 1;
     public static boolean logPeripheralErrors = false;
 
+    public static int computer_threads = 1;
+    public static long maxMainGlobalTime = TimeUnit.MILLISECONDS.toNanos( 10 );
+    public static long maxMainComputerTime = TimeUnit.MILLISECONDS.toNanos( 5 );
+
     public static boolean http_enable = true;
     public static boolean http_websocket_enable = true;
     public static AddressPredicate http_whitelist = new AddressPredicate( DEFAULT_HTTP_WHITELIST );
@@ -172,48 +110,56 @@ public class ComputerCraft
     public static final int terminalHeight_pocketComputer = 20;
 
     // Blocks and Items
-    public static class Blocks
+    public static final class Blocks
     {
-        public static BlockComputer computer;
+        public static BlockComputer computerNormal;
-        public static BlockCommandComputer commandComputer;
+        public static BlockComputer computerAdvanced;
+        public static BlockComputer computerCommand;
 
-        public static BlockTurtle turtle;
+        public static BlockTurtle turtleNormal;
-        public static BlockTurtle turtleExpanded;
         public static BlockTurtle turtleAdvanced;
 
-        public static BlockPeripheral peripheral;
+        public static BlockSpeaker speaker;
-        public static BlockCable cable;
+        public static BlockDiskDrive diskDrive;
-        public static BlockAdvancedModem advancedModem;
+        public static BlockPrinter printer;
+
+        public static BlockMonitor monitorNormal;
+        public static BlockMonitor monitorAdvanced;
+
+        public static BlockWirelessModem wirelessModemNormal;
+        public static BlockWirelessModem wirelessModemAdvanced;
+
         public static BlockWiredModemFull wiredModemFull;
+        public static BlockCable cable;
     }
 
-    public static class Items
+    public static final class Items
     {
-        public static ItemComputer computer;
+        public static ItemComputer computerNormal;
-        public static ItemCommandComputer commandComputer;
+        public static ItemComputer computerAdvanced;
+        public static ItemComputer computerCommand;
 
-        public static ItemTurtleLegacy turtle;
+        public static ItemPocketComputer pocketComputerNormal;
-        public static ItemTurtleNormal turtleExpanded;
+        public static ItemPocketComputer pocketComputerAdvanced;
-        public static ItemTurtleAdvanced turtleAdvanced;
 
-        public static ItemPocketComputer pocketComputer;
+        public static ItemTurtle turtleNormal;
+        public static ItemTurtle turtleAdvanced;
 
-        public static ItemDiskLegacy disk;
+        public static ItemDisk disk;
-        public static ItemDiskExpanded diskExpanded;
         public static ItemTreasureDisk treasureDisk;
 
-        public static ItemPrintout printout;
+        public static ItemPrintout printedPage;
+        public static ItemPrintout printedPages;
+        public static ItemPrintout printedBook;
 
-        public static ItemPeripheral peripheral;
+        public static ItemBlockCable.Cable cable;
-        public static ItemAdvancedModem advancedModem;
+        public static ItemBlockCable.WiredModem wiredModem;
-        public static ItemCable cable;
-        public static ItemBlock wiredModemFull;
     }
 
-    public static class TurtleUpgrades
+    public static final class TurtleUpgrades
     {
-        public static TurtleModem wirelessModem;
+        public static TurtleModem wirelessModemNormal;
-        public static TurtleModem advancedModem;
+        public static TurtleModem wirelessModemAdvanced;
         public static TurtleSpeaker speaker;
 
         public static TurtleCraftingTable craftingTable;
@@ -224,99 +170,23 @@ public class ComputerCraft
         public static TurtleHoe diamondHoe;
     }
 
-    public static class PocketUpgrades
+    public static final class PocketUpgrades
     {
-        public static PocketModem wirelessModem;
+        public static PocketModem wirelessModemNormal;
-        public static PocketModem advancedModem;
+        public static PocketModem wirelessModemAdvanced;
         public static PocketSpeaker speaker;
-
-        @Deprecated
-        public static PocketSpeaker pocketSpeaker;
-    }
-
-    @Deprecated
-    public static class Upgrades
-    {
-        public static TurtleModem advancedModem;
     }
 
     // Registries
     public static final ClientComputerRegistry clientComputerRegistry = new ClientComputerRegistry();
     public static final ServerComputerRegistry serverComputerRegistry = new ServerComputerRegistry();
 
-    // Creative
-    public static CreativeTabMain mainCreativeTab;
-
     // Logging
-    public static Logger log;
+    public static final Logger log = LogManager.getLogger( MOD_ID );
 
-    // Peripheral providers. This is still here to ensure compatibility with Plethora and Computronics
+    public ComputerCraft()
-    public static List<IPeripheralProvider> peripheralProviders = new ArrayList<>();
-
-    // Implementation
-    @Mod.Instance( value = ComputerCraft.MOD_ID )
-    public static ComputerCraft instance;
-
-    @SidedProxy(
-        clientSide = "dan200.computercraft.client.proxy.ComputerCraftProxyClient",
-        serverSide = "dan200.computercraft.shared.proxy.ComputerCraftProxyCommon"
-    )
-    private static IComputerCraftProxy proxy;
-
-    @SidedProxy(
-        clientSide = "dan200.computercraft.client.proxy.CCTurtleProxyClient",
-        serverSide = "dan200.computercraft.shared.proxy.CCTurtleProxyCommon"
-    )
-    private static ICCTurtleProxy turtleProxy;
-
-    @Mod.EventHandler
-    public void preInit( FMLPreInitializationEvent event )
     {
-        log = event.getModLog();
+        Config.load();
-
-        // Load config
-        Config.load( event.getSuggestedConfigurationFile() );
-
-        // Setup network
-        NetworkHandler.setup();
-
-        proxy.preInit();
-        turtleProxy.preInit();
-    }
-
-    @Mod.EventHandler
-    public void init( FMLInitializationEvent event )
-    {
-        proxy.init();
-        turtleProxy.init();
-    }
-
-    @Mod.EventHandler
-    public void onServerStarting( FMLServerStartingEvent event )
-    {
-        proxy.initServer( event.getServer() );
-    }
-
-    @Mod.EventHandler
-    public void onServerStart( FMLServerStartedEvent event )
-    {
-        if( FMLCommonHandler.instance().getEffectiveSide() == Side.SERVER )
-        {
-            ComputerCraft.serverComputerRegistry.reset();
-            WirelessNetwork.resetNetworks();
-            Tracking.reset();
-        }
-    }
-
-    @Mod.EventHandler
-    public void onServerStopped( FMLServerStoppedEvent event )
-    {
-        if( FMLCommonHandler.instance().getEffectiveSide() == Side.SERVER )
-        {
-            ComputerCraft.serverComputerRegistry.reset();
-            WirelessNetwork.resetNetworks();
-            Tracking.reset();
-        }
     }
 
     public static String getVersion()
@@ -324,411 +194,23 @@ public class ComputerCraft
         return "${version}";
     }
 
-    public static void openDiskDriveGUI( EntityPlayer player, TileDiskDrive drive )
+    static IMount createResourceMount( String domain, String subPath )
     {
-        BlockPos pos = drive.getPos();
+        IReloadableResourceManager manager = ServerLifecycleHooks.getCurrentServer().getResourceManager();
-        player.openGui( ComputerCraft.instance, ComputerCraft.diskDriveGUIID, player.getEntityWorld(), pos.getX(), pos.getY(), pos.getZ() );
+        ResourceMount mount = new ResourceMount( domain, subPath, manager );
+        return mount.exists( "" ) ? mount : null;
     }
 
-    public static void openComputerGUI( EntityPlayer player, TileComputer computer )
+    public static InputStream getResourceFile( String domain, String subPath )
-    {
-        BlockPos pos = computer.getPos();
-        player.openGui( ComputerCraft.instance, ComputerCraft.computerGUIID, player.getEntityWorld(), pos.getX(), pos.getY(), pos.getZ() );
-    }
-
-    public static void openPrinterGUI( EntityPlayer player, TilePrinter printer )
-    {
-        BlockPos pos = printer.getPos();
-        player.openGui( ComputerCraft.instance, ComputerCraft.printerGUIID, player.getEntityWorld(), pos.getX(), pos.getY(), pos.getZ() );
-    }
-
-    public static void openTurtleGUI( EntityPlayer player, TileTurtle turtle )
-    {
-        BlockPos pos = turtle.getPos();
-        player.openGui( instance, ComputerCraft.turtleGUIID, player.getEntityWorld(), pos.getX(), pos.getY(), pos.getZ() );
-    }
-
-    public static void openPrintoutGUI( EntityPlayer player, EnumHand hand )
-    {
-        player.openGui( ComputerCraft.instance, ComputerCraft.printoutGUIID, player.getEntityWorld(), hand.ordinal(), 0, 0 );
-    }
-
-    public static void openPocketComputerGUI( EntityPlayer player, EnumHand hand )
-    {
-        player.openGui( ComputerCraft.instance, ComputerCraft.pocketComputerGUIID, player.getEntityWorld(), hand.ordinal(), 0, 0 );
-    }
-
-    public static void openComputerGUI( EntityPlayer player, ServerComputer computer )
-    {
-        ComputerFamily family = computer.getFamily();
-        int width = 0, height = 0;
-        Terminal terminal = computer.getTerminal();
-        if( terminal != null )
-        {
-            width = terminal.getWidth();
-            height = terminal.getHeight();
-        }
-
-        // Pack useful terminal information into the various coordinate bits.
-        // These are extracted in ComputerCraftProxyCommon.getClientGuiElement
-        player.openGui( ComputerCraft.instance, ComputerCraft.viewComputerGUIID, player.getEntityWorld(),
-            computer.getInstanceID(), family.ordinal(), (width & 0xFFFF) << 16 | (height & 0xFFFF)
-        );
-    }
-
-    private static File getBaseDir()
-    {
-        return FMLCommonHandler.instance().getMinecraftServerInstance().getDataDirectory();
-    }
-
-    private static File getResourcePackDir()
-    {
-        return new File( getBaseDir(), "resourcepacks" );
-    }
-
-    public static boolean canPlayerUseCommands( EntityPlayer player )
-    {
-        MinecraftServer server = player.getServer();
-        if( server != null )
-        {
-            return server.getPlayerList().canSendCommands( player.getGameProfile() );
-        }
-        return false;
-    }
-
-    @Deprecated
-    public static void registerPermissionProvider( ITurtlePermissionProvider provider )
-    {
-        TurtlePermissions.register( provider );
-    }
-
-    @Deprecated
-    public static void registerPocketUpgrade( IPocketUpgrade upgrade )
-    {
-        dan200.computercraft.shared.PocketUpgrades.register( upgrade );
-    }
-
-    @Deprecated
-    public static void registerPeripheralProvider( IPeripheralProvider provider )
-    {
-        Peripherals.register( provider );
-    }
-
-    @Deprecated
-    public static void registerBundledRedstoneProvider( IBundledRedstoneProvider provider )
-    {
-        BundledRedstone.register( provider );
-    }
-
-    @Deprecated
-    public static void registerMediaProvider( IMediaProvider provider )
-    {
-        MediaProviders.register( provider );
-    }
-
-    @Deprecated
-    public static void registerAPIFactory( ILuaAPIFactory factory )
-    {
-        ApiFactories.register( factory );
-    }
-
-    @Deprecated
-    public static IWiredNode createWiredNodeForElement( IWiredElement element )
-    {
-        return new WiredNode( element );
-    }
-
-    @Deprecated
-    public static IWiredElement getWiredElementAt( IBlockAccess world, BlockPos pos, EnumFacing side )
-    {
-        TileEntity tile = world.getTileEntity( pos );
-        return tile != null && tile.hasCapability( CapabilityWiredElement.CAPABILITY, side )
-            ? tile.getCapability( CapabilityWiredElement.CAPABILITY, side )
-            : null;
-    }
-
-    @Deprecated
-    public static int getDefaultBundledRedstoneOutput( World world, BlockPos pos, EnumFacing side )
-    {
-        return BundledRedstone.getDefaultOutput( world, pos, side );
-    }
-
-    @Deprecated
-    public static IPacketNetwork getWirelessNetwork()
-    {
-        return WirelessNetwork.getUniversal();
-    }
-
-    @Deprecated
-    public static int createUniqueNumberedSaveDir( World world, String parentSubPath )
-    {
-        return IDAssigner.getNextIDFromDirectory( parentSubPath );
-    }
-
-    @Deprecated
-    public static IWritableMount createSaveDirMount( World world, String subPath, long capacity )
     {
+        IReloadableResourceManager manager = ServerLifecycleHooks.getCurrentServer().getResourceManager();
         try
         {
-            return new FileMount( new File( getWorldDir(), subPath ), capacity );
+            return manager.getResource( new ResourceLocation( domain, subPath ) ).getInputStream();
         }
-        catch( Exception e )
+        catch( IOException ignored )
         {
             return null;
         }
     }
-
-    @Deprecated
-    public static IMount createResourceMount( Class<?> modClass, String domain, String subPath )
-    {
-        // Start building list of mounts
-        List<IMount> mounts = new ArrayList<>();
-        subPath = "assets/" + domain + "/" + subPath;
-
-        // Mount from debug dir
-        File codeDir = getDebugCodeDir( modClass );
-        if( codeDir != null )
-        {
-            File subResource = new File( codeDir, subPath );
-            if( subResource.exists() )
-            {
-                IMount resourcePackMount = new FileMount( subResource, 0 );
-                mounts.add( resourcePackMount );
-            }
-        }
-
-        // Mount from mod jar
-        File modJar = getContainingJar( modClass );
-        if( modJar != null )
-        {
-            try
-            {
-                mounts.add( new JarMount( modJar, subPath ) );
-            }
-            catch( IOException | RuntimeException e )
-            {
-                ComputerCraft.log.error( "Could not load mount from mod jar", e );
-            }
-        }
-
-        // Mount from resource packs
-        File resourcePackDir = getResourcePackDir();
-        if( resourcePackDir.exists() && resourcePackDir.isDirectory() )
-        {
-            String[] resourcePacks = resourcePackDir.list();
-            for( String resourcePackName : resourcePacks )
-            {
-                try
-                {
-                    File resourcePack = new File( resourcePackDir, resourcePackName );
-                    if( !resourcePack.isDirectory() )
-                    {
-                        // Mount a resource pack from a jar
-                        mounts.add( new JarMount( resourcePack, subPath ) );
-                    }
-                    else
-                    {
-                        // Mount a resource pack from a folder
-                        File subResource = new File( resourcePack, subPath );
-                        if( subResource.exists() ) mounts.add( new FileMount( subResource, 0 ) );
-                    }
-                }
-                catch( IOException | RuntimeException e )
-                {
-                    ComputerCraft.log.error( "Could not load resource pack '" + resourcePackName + "'", e );
-                }
-            }
-        }
-
-        // Return the combination of all the mounts found
-        if( mounts.size() >= 2 )
-        {
-            IMount[] mountArray = new IMount[mounts.size()];
-            mounts.toArray( mountArray );
-            return new ComboMount( mountArray );
-        }
-        else if( mounts.size() == 1 )
-        {
-            return mounts.get( 0 );
-        }
-        else
-        {
-            return null;
-        }
-    }
-
-    public static InputStream getResourceFile( Class<?> modClass, String domain, String subPath )
-    {
-        // Start searching in possible locations
-        subPath = "assets/" + domain + "/" + subPath;
-
-        // Look in resource packs
-        File resourcePackDir = getResourcePackDir();
-        if( resourcePackDir.exists() && resourcePackDir.isDirectory() )
-        {
-            String[] resourcePacks = resourcePackDir.list();
-            for( String resourcePackPath : resourcePacks )
-            {
-                File resourcePack = new File( resourcePackDir, resourcePackPath );
-                if( resourcePack.isDirectory() )
-                {
-                    // Mount a resource pack from a folder
-                    File subResource = new File( resourcePack, subPath );
-                    if( subResource.exists() && subResource.isFile() )
-                    {
-                        try
-                        {
-                            return new FileInputStream( subResource );
-                        }
-                        catch( FileNotFoundException ignored )
-                        {
-                        }
-                    }
-                }
-                else
-                {
-                    ZipFile zipFile = null;
-                    try
-                    {
-                        final ZipFile zip = zipFile = new ZipFile( resourcePack );
-                        ZipEntry entry = zipFile.getEntry( subPath );
-                        if( entry != null )
-                        {
-                            // Return a custom InputStream which will close the original zip when finished.
-                            return new FilterInputStream( zipFile.getInputStream( entry ) )
-                            {
-                                @Override
-                                public void close() throws IOException
-                                {
-                                    super.close();
-                                    zip.close();
-                                }
-                            };
-                        }
-                        else
-                        {
-                            IoUtil.closeQuietly( zipFile );
-                        }
-                    }
-                    catch( IOException e )
-                    {
-                        if( zipFile != null ) IoUtil.closeQuietly( zipFile );
-                    }
-                }
-            }
-        }
-
-        // Look in debug dir
-        File codeDir = getDebugCodeDir( modClass );
-        if( codeDir != null )
-        {
-            File subResource = new File( codeDir, subPath );
-            if( subResource.exists() && subResource.isFile() )
-            {
-                try
-                {
-                    return new FileInputStream( subResource );
-                }
-                catch( FileNotFoundException ignored )
-                {
-                }
-            }
-        }
-
-        // Look in class loader
-        return modClass.getClassLoader().getResourceAsStream( subPath );
-    }
-
-    private static File getContainingJar( Class<?> modClass )
-    {
-        String path = modClass.getProtectionDomain().getCodeSource().getLocation().getPath();
-        int bangIndex = path.indexOf( "!" );
-        if( bangIndex >= 0 )
-        {
-            path = path.substring( 0, bangIndex );
-        }
-
-        URL url;
-        try
-        {
-            url = new URL( path );
-        }
-        catch( MalformedURLException e1 )
-        {
-            return null;
-        }
-
-        File file;
-        try
-        {
-            file = new File( url.toURI() );
-        }
-        catch( URISyntaxException e )
-        {
-            file = new File( url.getPath() );
-        }
-        return file;
-    }
-
-    private static File getDebugCodeDir( Class<?> modClass )
-    {
-        String path = modClass.getProtectionDomain().getCodeSource().getLocation().getPath();
-        int bangIndex = path.indexOf( "!" );
-        return bangIndex >= 0 ? null : new File( new File( path ).getParentFile(), "../.." );
-    }
-
-    @Deprecated
-    public static void registerTurtleUpgrade( ITurtleUpgrade upgrade )
-    {
-        dan200.computercraft.shared.TurtleUpgrades.register( upgrade );
-    }
-
-    public static File getWorldDir()
-    {
-        return DimensionManager.getCurrentSaveRootDirectory();
-    }
-
-    //region Compatibility
-    @Deprecated
-    public static File getWorldDir( World world )
-    {
-        return DimensionManager.getCurrentSaveRootDirectory();
-    }
-
-    @Deprecated
-    public static IMedia getMedia( ItemStack stack )
-    {
-        return MediaProviders.get( stack );
-    }
-
-    @Deprecated
-    public static IPocketUpgrade getPocketUpgrade( ItemStack stack )
-    {
-        return dan200.computercraft.shared.PocketUpgrades.get( stack );
-    }
-
-    @Deprecated
-    public static ITurtleUpgrade getTurtleUpgrade( ItemStack stack )
-    {
-        return dan200.computercraft.shared.TurtleUpgrades.get( stack );
-    }
-
-    @Deprecated
-    public static IPocketUpgrade getPocketUpgrade( String id )
-    {
-        return dan200.computercraft.shared.PocketUpgrades.get( id );
-    }
-
-    @Deprecated
-    public static ITurtleUpgrade getTurtleUpgrade( String id )
-    {
-        return dan200.computercraft.shared.TurtleUpgrades.get( id );
-    }
-
-    @Deprecated
-    public static IPeripheral getPeripheralAt( World world, BlockPos pos, EnumFacing side )
-    {
-        return Peripherals.getPeripheral( world, pos, side );
-    }
-    //endregion
 }

src/main/java/dan200/computercraft/ComputerCraftAPIImpl.java

@@ -0,0 +1,141 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+
+package dan200.computercraft;
+
+import dan200.computercraft.api.ComputerCraftAPI.IComputerCraftAPI;
+import dan200.computercraft.api.filesystem.IMount;
+import dan200.computercraft.api.filesystem.IWritableMount;
+import dan200.computercraft.api.lua.ILuaAPIFactory;
+import dan200.computercraft.api.media.IMediaProvider;
+import dan200.computercraft.api.network.IPacketNetwork;
+import dan200.computercraft.api.network.wired.IWiredElement;
+import dan200.computercraft.api.network.wired.IWiredNode;
+import dan200.computercraft.api.peripheral.IPeripheralProvider;
+import dan200.computercraft.api.pocket.IPocketUpgrade;
+import dan200.computercraft.api.redstone.IBundledRedstoneProvider;
+import dan200.computercraft.api.turtle.ITurtleUpgrade;
+import dan200.computercraft.core.apis.ApiFactories;
+import dan200.computercraft.core.filesystem.FileMount;
+import dan200.computercraft.shared.*;
+import dan200.computercraft.shared.peripheral.modem.wireless.WirelessNetwork;
+import dan200.computercraft.shared.util.IDAssigner;
+import dan200.computercraft.shared.wired.CapabilityWiredElement;
+import dan200.computercraft.shared.wired.WiredNode;
+import net.minecraft.tileentity.TileEntity;
+import net.minecraft.util.EnumFacing;
+import net.minecraft.util.math.BlockPos;
+import net.minecraft.world.IBlockReader;
+import net.minecraft.world.World;
+import net.minecraftforge.common.util.LazyOptional;
+
+import javax.annotation.Nonnull;
+import java.io.File;
+
+public final class ComputerCraftAPIImpl implements IComputerCraftAPI
+{
+    public static final ComputerCraftAPIImpl INSTANCE = new ComputerCraftAPIImpl();
+
+    private ComputerCraftAPIImpl()
+    {
+    }
+
+    @Nonnull
+    @Override
+    public String getInstalledVersion()
+    {
+        return "${version}";
+    }
+
+    @Override
+    public int createUniqueNumberedSaveDir( @Nonnull World world, @Nonnull String parentSubPath )
+    {
+        return IDAssigner.getNextId( parentSubPath );
+    }
+
+    @Override
+    public IWritableMount createSaveDirMount( @Nonnull World world, @Nonnull String subPath, long capacity )
+    {
+        try
+        {
+            return new FileMount( new File( IDAssigner.getDir(), subPath ), capacity );
+        }
+        catch( Exception e )
+        {
+            return null;
+        }
+    }
+
+    @Override
+    public IMount createResourceMount( @Nonnull String domain, @Nonnull String subPath )
+    {
+        return ComputerCraft.createResourceMount( domain, subPath );
+    }
+
+    @Override
+    public void registerPeripheralProvider( @Nonnull IPeripheralProvider provider )
+    {
+        Peripherals.register( provider );
+    }
+
+    @Override
+    public void registerTurtleUpgrade( @Nonnull ITurtleUpgrade upgrade )
+    {
+        TurtleUpgrades.register( upgrade );
+    }
+
+    @Override
+    public void registerBundledRedstoneProvider( @Nonnull IBundledRedstoneProvider provider )
+    {
+        BundledRedstone.register( provider );
+    }
+
+    @Override
+    public int getBundledRedstoneOutput( @Nonnull World world, @Nonnull BlockPos pos, @Nonnull EnumFacing side )
+    {
+        return BundledRedstone.getDefaultOutput( world, pos, side );
+    }
+
+    @Override
+    public void registerMediaProvider( @Nonnull IMediaProvider provider )
+    {
+        MediaProviders.register( provider );
+    }
+
+    @Override
+    public void registerPocketUpgrade( @Nonnull IPocketUpgrade upgrade )
+    {
+        PocketUpgrades.register( upgrade );
+    }
+
+    @Nonnull
+    @Override
+    public IPacketNetwork getWirelessNetwork()
+    {
+        return WirelessNetwork.getUniversal();
+    }
+
+    @Override
+    public void registerAPIFactory( @Nonnull ILuaAPIFactory factory )
+    {
+        ApiFactories.register( factory );
+    }
+
+    @Nonnull
+    @Override
+    public IWiredNode createWiredNodeForElement( @Nonnull IWiredElement element )
+    {
+        return new WiredNode( element );
+    }
+
+    @Nonnull
+    @Override
+    public LazyOptional<IWiredElement> getWiredElementAt( @Nonnull IBlockReader world, @Nonnull BlockPos pos, @Nonnull EnumFacing side )
+    {
+        TileEntity tile = world.getTileEntity( pos );
+        return tile == null ? LazyOptional.empty() : tile.getCapability( CapabilityWiredElement.CAPABILITY, side );
+    }
+}

src/main/java/dan200/computercraft/api/AbstractTurtleUpgrade.java

@@ -4,57 +4,50 @@
  * Send enquiries to dratcliffe@gmail.com
  */
 
-package dan200.computercraft.shared.turtle.upgrades;
+package dan200.computercraft.api;
 
 import dan200.computercraft.api.turtle.ITurtleUpgrade;
 import dan200.computercraft.api.turtle.TurtleUpgradeType;
-import net.minecraft.block.Block;
-import net.minecraft.item.Item;
 import net.minecraft.item.ItemStack;
+import net.minecraft.util.IItemProvider;
 import net.minecraft.util.ResourceLocation;
+import net.minecraft.util.Util;
 
 import javax.annotation.Nonnull;
 
+/**
+ * A base class for {@link ITurtleUpgrade}s.
+ *
+ * One does not have to use this, but it does provide a convenient template.
+ */
 public abstract class AbstractTurtleUpgrade implements ITurtleUpgrade
 {
     private final ResourceLocation id;
-    private final int legacyId;
     private final TurtleUpgradeType type;
     private final String adjective;
     private final ItemStack stack;
 
-    public AbstractTurtleUpgrade( ResourceLocation id, int legacyId, TurtleUpgradeType type, String adjective, ItemStack stack )
+    protected AbstractTurtleUpgrade( ResourceLocation id, TurtleUpgradeType type, String adjective, ItemStack stack )
     {
         this.id = id;
-        this.legacyId = legacyId;
         this.type = type;
         this.adjective = adjective;
         this.stack = stack;
     }
 
-    public AbstractTurtleUpgrade( ResourceLocation id, int legacyId, TurtleUpgradeType type, String adjective, Item item )
+    protected AbstractTurtleUpgrade( ResourceLocation id, TurtleUpgradeType type, String adjective, IItemProvider item )
     {
-        this( id, legacyId, type, adjective, new ItemStack( item ) );
+        this( id, type, adjective, new ItemStack( item ) );
     }
 
-    public AbstractTurtleUpgrade( ResourceLocation id, int legacyId, TurtleUpgradeType type, String adjective, Block block )
+    protected AbstractTurtleUpgrade( ResourceLocation id, TurtleUpgradeType type, ItemStack stack )
     {
-        this( id, legacyId, type, adjective, new ItemStack( block ) );
+        this( id, type, Util.makeTranslationKey( "upgrade", id ) + ".adjective", stack );
     }
 
-    public AbstractTurtleUpgrade( ResourceLocation id, int legacyId, TurtleUpgradeType type, ItemStack stack )
+    protected AbstractTurtleUpgrade( ResourceLocation id, TurtleUpgradeType type, IItemProvider item )
     {
-        this( id, legacyId, type, "upgrade." + id + ".adjective", stack );
+        this( id, type, new ItemStack( item ) );
-    }
-
-    public AbstractTurtleUpgrade( ResourceLocation id, int legacyId, TurtleUpgradeType type, Item item )
-    {
-        this( id, legacyId, type, new ItemStack( item ) );
-    }
-
-    public AbstractTurtleUpgrade( ResourceLocation id, int legacyId, TurtleUpgradeType type, Block block )
-    {
-        this( id, legacyId, type, new ItemStack( block ) );
     }
 
     @Nonnull
@@ -64,12 +57,6 @@ public abstract class AbstractTurtleUpgrade implements ITurtleUpgrade
         return id;
     }
 
-    @Override
-    public final int getLegacyUpgradeID()
-    {
-        return legacyId;
-    }
-
     @Nonnull
     @Override
     public final String getUnlocalisedAdjective()

src/main/java/dan200/computercraft/api/ComputerCraftAPI.java

@@ -17,18 +17,17 @@ import dan200.computercraft.api.network.wired.IWiredNode;
 import dan200.computercraft.api.peripheral.IComputerAccess;
 import dan200.computercraft.api.peripheral.IPeripheral;
 import dan200.computercraft.api.peripheral.IPeripheralProvider;
-import dan200.computercraft.api.permissions.ITurtlePermissionProvider;
 import dan200.computercraft.api.pocket.IPocketUpgrade;
 import dan200.computercraft.api.redstone.IBundledRedstoneProvider;
 import dan200.computercraft.api.turtle.ITurtleUpgrade;
 import net.minecraft.util.EnumFacing;
 import net.minecraft.util.math.BlockPos;
-import net.minecraft.world.IBlockAccess;
+import net.minecraft.world.IBlockReader;
 import net.minecraft.world.World;
+import net.minecraftforge.common.util.LazyOptional;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
-import java.lang.reflect.Method;
 
 /**
  * The static entry point to the ComputerCraft API.
@@ -37,28 +36,10 @@ import java.lang.reflect.Method;
  */
 public final class ComputerCraftAPI
 {
-    public static boolean isInstalled()
-    {
-        findCC();
-        return computerCraft != null;
-    }
-
     @Nonnull
     public static String getInstalledVersion()
     {
-        findCC();
+        return getInstance().getInstalledVersion();
-        if( computerCraft_getVersion != null )
-        {
-            try
-            {
-                return (String) computerCraft_getVersion.invoke( null );
-            }
-            catch( Exception e )
-            {
-                // It failed
-            }
-        }
-        return "";
     }
 
     @Nonnull
@@ -82,19 +63,7 @@ public final class ComputerCraftAPI
      */
     public static int createUniqueNumberedSaveDir( @Nonnull World world, @Nonnull String parentSubPath )
     {
-        findCC();
+        return getInstance().createUniqueNumberedSaveDir( world, parentSubPath );
-        if( computerCraft_createUniqueNumberedSaveDir != null )
-        {
-            try
-            {
-                return (Integer) computerCraft_createUniqueNumberedSaveDir.invoke( null, world, parentSubPath );
-            }
-            catch( Exception e )
-            {
-                // It failed
-            }
-        }
-        return -1;
     }
 
     /**
@@ -118,78 +87,66 @@ public final class ComputerCraftAPI
     @Nullable
     public static IWritableMount createSaveDirMount( @Nonnull World world, @Nonnull String subPath, long capacity )
     {
-        findCC();
+        return getInstance().createSaveDirMount( world, subPath, capacity );
-        if( computerCraft_createSaveDirMount != null )
-        {
-            try
-            {
-                return (IWritableMount) computerCraft_createSaveDirMount.invoke( null, world, subPath, capacity );
-            }
-            catch( Exception e )
-            {
-                // It failed
-            }
-        }
-        return null;
     }
 
     /**
      * Creates a file system mount to a resource folder, and returns it.
      *
-     * Use in conjunction with IComputerAccess.mount() or IComputerAccess.mountWritable() to mount a resource folder
+     * Use in conjunction with {@link IComputerAccess#mount} or {@link IComputerAccess#mountWritable} to mount a
-     * onto a computer's file system.
+     * resource folder onto a computer's file system.
      *
-     * The files in this mount will be a combination of files in the specified mod jar, and resource packs that contain
+     * The files in this mount will be a combination of files in all mod jar, and data packs that contain
      * resources with the same domain and path.
      *
-     * @param modClass A class in whose jar to look first for the resources to mount. Using your main mod class is recommended. eg: MyMod.class
+     * @param domain  The domain under which to look for resources. eg: "mymod".
-     * @param domain   The domain under which to look for resources. eg: "mymod".
+     * @param subPath The subPath under which to look for resources. eg: "lua/myfiles".
-     * @param subPath  The domain under which to look for resources. eg: "mymod/lua/myfiles".
+     * @return The mount, or {@code null} if it could be created for some reason.
-     * @return The mount, or {@code null} if it could be created for some reason. Use IComputerAccess.mount() or
-     * IComputerAccess.mountWritable() to mount this on a Computers' file system.
      * @see IComputerAccess#mount(String, IMount)
      * @see IComputerAccess#mountWritable(String, IWritableMount)
      * @see IMount
      */
     @Nullable
-    public static IMount createResourceMount( @Nonnull Class<?> modClass, @Nonnull String domain, @Nonnull String subPath )
+    public static IMount createResourceMount( @Nonnull String domain, @Nonnull String subPath )
     {
-        findCC();
+        return getInstance().createResourceMount( domain, subPath );
-        if( computerCraft_createResourceMount != null )
+    }
-        {
+
-            try
+    /**
-            {
+     * Creates a file system mount to a resource folder, and returns it.
-                return (IMount) computerCraft_createResourceMount.invoke( null, modClass, domain, subPath );
+     *
-            }
+     * Use in conjunction with {@link IComputerAccess#mount} or {@link IComputerAccess#mountWritable} to mount a
-            catch( Exception e )
+     * resource folder onto a computer's file system.
-            {
+     *
-                // It failed
+     * The files in this mount will be a combination of files in all mod jar, and data packs that contain
-            }
+     * resources with the same domain and path.
-        }
+     *
-        return null;
+     * @param klass   The mod class to which the files belong.
+     * @param domain  The domain under which to look for resources. eg: "mymod".
+     * @param subPath The subPath under which to look for resources. eg: "lua/myfiles".
+     * @return The mount, or {@code null} if it could be created for some reason.
+     * @see IComputerAccess#mount(String, IMount)
+     * @see IComputerAccess#mountWritable(String, IWritableMount)
+     * @see IMount
+     * @deprecated Use {@link #createResourceMount(String, String)} instead.
+     */
+    @Nullable
+    @Deprecated
+    public static IMount createResourceMount( Class<?> klass, @Nonnull String domain, @Nonnull String subPath )
+    {
+        return getInstance().createResourceMount( domain, subPath );
     }
 
     /**
      * Registers a peripheral provider to convert blocks into {@link IPeripheral} implementations.
      *
      * @param provider The peripheral provider to register.
-     * @see dan200.computercraft.api.peripheral.IPeripheral
+     * @see IPeripheral
-     * @see dan200.computercraft.api.peripheral.IPeripheralProvider
+     * @see IPeripheralProvider
      */
     public static void registerPeripheralProvider( @Nonnull IPeripheralProvider provider )
     {
-        findCC();
+        getInstance().registerPeripheralProvider( provider );
-        if( computerCraft_registerPeripheralProvider != null )
-        {
-            try
-            {
-                computerCraft_registerPeripheralProvider.invoke( null, provider );
-            }
-            catch( Exception e )
-            {
-                // It failed
-            }
-        }
     }
 
     /**
@@ -198,47 +155,22 @@ public final class ComputerCraftAPI
      * this during the load() method of your mod.
      *
      * @param upgrade The turtle upgrade to register.
-     * @see dan200.computercraft.api.turtle.ITurtleUpgrade
+     * @see ITurtleUpgrade
      */
     public static void registerTurtleUpgrade( @Nonnull ITurtleUpgrade upgrade )
     {
-        if( upgrade != null )
+        getInstance().registerTurtleUpgrade( upgrade );
-        {
-            findCC();
-            if( computerCraft_registerTurtleUpgrade != null )
-            {
-                try
-                {
-                    computerCraft_registerTurtleUpgrade.invoke( null, upgrade );
-                }
-                catch( Exception e )
-                {
-                    // It failed
-                }
-            }
-        }
     }
 
     /**
      * Registers a bundled redstone provider to provide bundled redstone output for blocks.
      *
      * @param provider The bundled redstone provider to register.
-     * @see dan200.computercraft.api.redstone.IBundledRedstoneProvider
+     * @see IBundledRedstoneProvider
      */
     public static void registerBundledRedstoneProvider( @Nonnull IBundledRedstoneProvider provider )
     {
-        findCC();
+        getInstance().registerBundledRedstoneProvider( provider );
-        if( computerCraft_registerBundledRedstoneProvider != null )
-        {
-            try
-            {
-                computerCraft_registerBundledRedstoneProvider.invoke( null, provider );
-            }
-            catch( Exception e )
-            {
-                // It failed
-            }
-        }
     }
 
     /**
@@ -249,85 +181,27 @@ public final class ComputerCraftAPI
      * @param side  The side to extract the bundled redstone output from.
      * @return If there is a block capable of emitting bundled redstone at the location, it's signal (0-65535) will be returned.
      * If there is no block capable of emitting bundled redstone at the location, -1 will be returned.
-     * @see dan200.computercraft.api.redstone.IBundledRedstoneProvider
+     * @see IBundledRedstoneProvider
      */
     public static int getBundledRedstoneOutput( @Nonnull World world, @Nonnull BlockPos pos, @Nonnull EnumFacing side )
     {
-        findCC();
+        return getInstance().getBundledRedstoneOutput( world, pos, side );
-        if( computerCraft_getDefaultBundledRedstoneOutput != null )
-        {
-            try
-            {
-                return (Integer) computerCraft_getDefaultBundledRedstoneOutput.invoke( null, world, pos, side );
-            }
-            catch( Exception e )
-            {
-                // It failed
-            }
-        }
-        return -1;
     }
 
     /**
      * Registers a media provider to provide {@link IMedia} implementations for Items
      *
      * @param provider The media provider to register.
-     * @see dan200.computercraft.api.media.IMediaProvider
+     * @see IMediaProvider
      */
     public static void registerMediaProvider( @Nonnull IMediaProvider provider )
     {
-        findCC();
+        getInstance().registerMediaProvider( provider );
-        if( computerCraft_registerMediaProvider != null )
-        {
-            try
-            {
-                computerCraft_registerMediaProvider.invoke( null, provider );
-            }
-            catch( Exception e )
-            {
-                // It failed
-            }
-        }
-    }
-
-    /**
-     * Registers a permission provider to restrict where turtles can move or build.
-     *
-     * @param provider The turtle permission provider to register.
-     * @see dan200.computercraft.api.permissions.ITurtlePermissionProvider
-     * @deprecated Prefer using {@link dan200.computercraft.api.turtle.event.TurtleBlockEvent} or the standard Forge events.
-     */
-    @Deprecated
-    public static void registerPermissionProvider( @Nonnull ITurtlePermissionProvider provider )
-    {
-        findCC();
-        if( computerCraft_registerPermissionProvider != null )
-        {
-            try
-            {
-                computerCraft_registerPermissionProvider.invoke( null, provider );
-            }
-            catch( Exception e )
-            {
-                // It failed
-            }
-        }
     }
 
     public static void registerPocketUpgrade( @Nonnull IPocketUpgrade upgrade )
     {
-        findCC();
+        getInstance().registerPocketUpgrade( upgrade );
-        if( computerCraft_registerPocketUpgrade != null )
-        {
-            try
-            {
-                computerCraft_registerPocketUpgrade.invoke( null, upgrade );
-            }
-            catch( Exception e )
-            {
-                // It failed
-            }
-        }
     }
 
     /**
@@ -337,36 +211,12 @@ public final class ComputerCraftAPI
      */
     public static IPacketNetwork getWirelessNetwork()
     {
-        findCC();
+        return getInstance().getWirelessNetwork();
-        if( computerCraft_getWirelessNetwork != null )
-        {
-            try
-            {
-                return (IPacketNetwork) computerCraft_getWirelessNetwork.invoke( null );
-            }
-            catch( Exception e )
-            {
-                // It failed;
-            }
-        }
-
-        return null;
     }
 
-    public static void registerAPIFactory( @Nonnull ILuaAPIFactory upgrade )
+    public static void registerAPIFactory( @Nonnull ILuaAPIFactory factory )
     {
-        findCC();
+        getInstance().registerAPIFactory( factory );
-        if( computerCraft_registerAPIFactory != null )
-        {
-            try
-            {
-                computerCraft_registerAPIFactory.invoke( null, upgrade );
-            }
-            catch( Exception e )
-            {
-                // It failed
-            }
-        }
     }
 
     /**
@@ -379,22 +229,7 @@ public final class ComputerCraftAPI
     @Nonnull
     public static IWiredNode createWiredNodeForElement( @Nonnull IWiredElement element )
     {
-        findCC();
+        return getInstance().createWiredNodeForElement( element );
-        if( computerCraft_createWiredNodeForElement != null )
-        {
-            try
-            {
-                return (IWiredNode) computerCraft_createWiredNodeForElement.invoke( null, element );
-            }
-            catch( ReflectiveOperationException e )
-            {
-                throw new IllegalStateException( "Error creating wired node", e );
-            }
-        }
-        else
-        {
-            throw new IllegalStateException( "ComputerCraft cannot be found" );
-        }
     }
 
     /**
@@ -406,118 +241,64 @@ public final class ComputerCraftAPI
      * @return The element's node
      * @see IWiredElement#getNode()
      */
-    @Nullable
+    @Nonnull
-    public static IWiredElement getWiredElementAt( @Nonnull IBlockAccess world, @Nonnull BlockPos pos, @Nonnull EnumFacing side )
+    public static LazyOptional<IWiredElement> getWiredElementAt( @Nonnull IBlockReader world, @Nonnull BlockPos pos, @Nonnull EnumFacing side )
     {
-        findCC();
+        return getInstance().getWiredElementAt( world, pos, side );
-        if( computerCraft_getWiredElementAt != null )
-        {
-            try
-            {
-                return (IWiredElement) computerCraft_getWiredElementAt.invoke( null, world, pos, side );
-            }
-            catch( ReflectiveOperationException ignored )
-            {
-            }
-        }
-
-        return null;
     }
 
-    // The functions below here are private, and are used to interface with the non-API ComputerCraft classes.
+    private static IComputerCraftAPI instance;
-    // Reflection is used here so you can develop your mod without decompiling ComputerCraft and including
-    // it in your solution, and so your mod won't crash if ComputerCraft is installed.
 
-    private static void findCC()
+    @Nonnull
+    private static IComputerCraftAPI getInstance()
     {
-        if( !ccSearched )
+        if( instance != null ) return instance;
-        {
-            try
-            {
-                computerCraft = Class.forName( "dan200.computercraft.ComputerCraft" );
-                computerCraft_getVersion = findCCMethod( "getVersion", new Class<?>[] {
-                } );
-                computerCraft_createUniqueNumberedSaveDir = findCCMethod( "createUniqueNumberedSaveDir", new Class<?>[] {
-                    World.class, String.class
-                } );
-                computerCraft_createSaveDirMount = findCCMethod( "createSaveDirMount", new Class<?>[] {
-                    World.class, String.class, Long.TYPE
-                } );
-                computerCraft_createResourceMount = findCCMethod( "createResourceMount", new Class<?>[] {
-                    Class.class, String.class, String.class
-                } );
-                computerCraft_registerPeripheralProvider = findCCMethod( "registerPeripheralProvider", new Class<?>[] {
-                    IPeripheralProvider.class
-                } );
-                computerCraft_registerTurtleUpgrade = findCCMethod( "registerTurtleUpgrade", new Class<?>[] {
-                    ITurtleUpgrade.class
-                } );
-                computerCraft_registerBundledRedstoneProvider = findCCMethod( "registerBundledRedstoneProvider", new Class<?>[] {
-                    IBundledRedstoneProvider.class
-                } );
-                computerCraft_getDefaultBundledRedstoneOutput = findCCMethod( "getDefaultBundledRedstoneOutput", new Class<?>[] {
-                    World.class, BlockPos.class, EnumFacing.class
-                } );
-                computerCraft_registerMediaProvider = findCCMethod( "registerMediaProvider", new Class<?>[] {
-                    IMediaProvider.class
-                } );
-                computerCraft_registerPermissionProvider = findCCMethod( "registerPermissionProvider", new Class<?>[] {
-                    ITurtlePermissionProvider.class
-                } );
-                computerCraft_registerPocketUpgrade = findCCMethod( "registerPocketUpgrade", new Class<?>[] {
-                    IPocketUpgrade.class
-                } );
-                computerCraft_getWirelessNetwork = findCCMethod( "getWirelessNetwork", new Class<?>[] {
-                } );
-                computerCraft_registerAPIFactory = findCCMethod( "registerAPIFactory", new Class<?>[] {
-                    ILuaAPIFactory.class
-                } );
-                computerCraft_createWiredNodeForElement = findCCMethod( "createWiredNodeForElement", new Class<?>[] {
-                    IWiredElement.class
-                } );
-                computerCraft_getWiredElementAt = findCCMethod( "getWiredElementAt", new Class<?>[] {
-                    IBlockAccess.class, BlockPos.class, EnumFacing.class
-                } );
-            }
-            catch( Exception e )
-            {
-                System.out.println( "ComputerCraftAPI: ComputerCraft not found." );
-            }
-            finally
-            {
-                ccSearched = true;
-            }
-        }
-    }
 
-    private static Method findCCMethod( String name, Class<?>[] args )
-    {
         try
         {
-            return computerCraft != null ? computerCraft.getMethod( name, args ) : null;
+            return instance = (IComputerCraftAPI) Class.forName( "dan200.computercraft.ComputerCraftAPIImpl" )
+                .getField( "INSTANCE" ).get( null );
         }
-        catch( NoSuchMethodException e )
+        catch( ReflectiveOperationException e )
         {
-            System.out.println( "ComputerCraftAPI: ComputerCraft method " + name + " not found." );
+            throw new IllegalStateException( "Cannot find ComputerCraft API", e );
-            return null;
         }
     }
 
-    private static boolean ccSearched = false;
+    public interface IComputerCraftAPI
-    private static Class<?> computerCraft = null;
+    {
-    private static Method computerCraft_getVersion = null;
+        @Nonnull
-    private static Method computerCraft_createUniqueNumberedSaveDir = null;
+        String getInstalledVersion();
-    private static Method computerCraft_createSaveDirMount = null;
+
-    private static Method computerCraft_createResourceMount = null;
+        int createUniqueNumberedSaveDir( @Nonnull World world, @Nonnull String parentSubPath );
-    private static Method computerCraft_registerPeripheralProvider = null;
+
-    private static Method computerCraft_registerTurtleUpgrade = null;
+        @Nullable
-    private static Method computerCraft_registerBundledRedstoneProvider = null;
+        IWritableMount createSaveDirMount( @Nonnull World world, @Nonnull String subPath, long capacity );
-    private static Method computerCraft_getDefaultBundledRedstoneOutput = null;
+
-    private static Method computerCraft_registerMediaProvider = null;
+        @Nullable
-    private static Method computerCraft_registerPermissionProvider = null;
+        IMount createResourceMount( @Nonnull String domain, @Nonnull String subPath );
-    private static Method computerCraft_registerPocketUpgrade = null;
+
-    private static Method computerCraft_getWirelessNetwork = null;
+        void registerPeripheralProvider( @Nonnull IPeripheralProvider provider );
-    private static Method computerCraft_registerAPIFactory = null;
+
-    private static Method computerCraft_createWiredNodeForElement = null;
+        void registerTurtleUpgrade( @Nonnull ITurtleUpgrade upgrade );
-    private static Method computerCraft_getWiredElementAt = null;
+
+        void registerBundledRedstoneProvider( @Nonnull IBundledRedstoneProvider provider );
+
+        int getBundledRedstoneOutput( @Nonnull World world, @Nonnull BlockPos pos, @Nonnull EnumFacing side );
+
+        void registerMediaProvider( @Nonnull IMediaProvider provider );
+
+        void registerPocketUpgrade( @Nonnull IPocketUpgrade upgrade );
+
+        @Nonnull
+        IPacketNetwork getWirelessNetwork();
+
+        void registerAPIFactory( @Nonnull ILuaAPIFactory factory );
+
+        @Nonnull
+        IWiredNode createWiredNodeForElement( @Nonnull IWiredElement element );
+
+        @Nonnull
+        LazyOptional<IWiredElement> getWiredElementAt( @Nonnull IBlockReader world, @Nonnull BlockPos pos, @Nonnull EnumFacing side );
+    }
 }

src/main/java/dan200/computercraft/api/filesystem/package-info.java

@@ -1,10 +0,0 @@
-/*
- * This file is part of the public ComputerCraft API - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2019. This API may be redistributed unmodified and in full only.
- * For help using the API, and posting your mods, visit the forums at computercraft.info.
- */
-
-@API( owner = "ComputerCraft", provides = "ComputerCraft|API|FileSystem", apiVersion = "${version}" )
-package dan200.computercraft.api.filesystem;
-
-import net.minecraftforge.fml.common.API;

src/main/java/dan200/computercraft/api/lua/ILuaAPIFactory.java

@@ -17,6 +17,7 @@ import javax.annotation.Nullable;
  * @see ILuaAPI
  * @see ComputerCraftAPI#registerAPIFactory(ILuaAPIFactory)
  */
+@FunctionalInterface
 public interface ILuaAPIFactory
 {
     /**

src/main/java/dan200/computercraft/api/lua/ILuaContext.java

@@ -32,7 +32,12 @@ public interface ILuaContext
      *                              intercepted, or the computer will leak memory and end up in a broken state.
      */
     @Nonnull
-    Object[] pullEvent( @Nullable String filter ) throws LuaException, InterruptedException;
+    default Object[] pullEvent( @Nullable String filter ) throws LuaException, InterruptedException
+    {
+        Object[] results = pullEventRaw( filter );
+        if( results.length >= 1 && results[0].equals( "terminate" ) ) throw new LuaException( "Terminated", 0 );
+        return results;
+    }
 
     /**
      * The same as {@link #pullEvent(String)}, except "terminated" events are ignored. Only use this if you want to
@@ -47,7 +52,10 @@ public interface ILuaContext
      * @see #pullEvent(String)
      */
     @Nonnull
-    Object[] pullEventRaw( @Nullable String filter ) throws InterruptedException;
+    default Object[] pullEventRaw( @Nullable String filter ) throws InterruptedException
+    {
+        return yield( new Object[] { filter } );
+    }
 
     /**
      * Yield the current coroutine with some arguments until it is resumed. This method is exactly equivalent to

src/main/java/dan200/computercraft/api/lua/package-info.java

@@ -1,10 +0,0 @@
-/*
- * This file is part of the public ComputerCraft API - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2019. This API may be redistributed unmodified and in full only.
- * For help using the API, and posting your mods, visit the forums at computercraft.info.
- */
-
-@API( owner = "ComputerCraft", provides = "ComputerCraft|API|Lua", apiVersion = "${version}" )
-package dan200.computercraft.api.lua;
-
-import net.minecraftforge.fml.common.API;

src/main/java/dan200/computercraft/api/media/IMedia.java

@@ -7,6 +7,7 @@
 package dan200.computercraft.api.media;
 
 import dan200.computercraft.api.filesystem.IMount;
+import net.minecraft.item.Item;
 import net.minecraft.item.ItemStack;
 import net.minecraft.util.SoundEvent;
 import net.minecraft.world.World;
@@ -16,7 +17,9 @@ import javax.annotation.Nullable;
 
 /**
  * Represents an item that can be placed in a disk drive and used by a Computer.
- * Implement this interface on your Item class to allow it to be used in the drive.
+ *
+ * Implement this interface on your {@link Item} class to allow it to be used in the drive. Alternatively, register
+ * a {@link IMediaProvider}.
  */
 public interface IMedia
 {
@@ -43,7 +46,7 @@ public interface IMedia
 
     /**
      * If this disk represents an item with audio (like a record), get the readable name of the audio track. ie:
-     * "Jonathon Coulton - Still Alive"
+     * "Jonathan Coulton - Still Alive"
      *
      * @param stack The {@link ItemStack} to modify.
      * @return The name, or null if this item does not represent an item with audio.
@@ -74,7 +77,7 @@ public interface IMedia
      * @param world The world in which the item and disk drive reside.
      * @return The mount, or null if this item does not represent an item with data. If the mount returned also
      * implements {@link dan200.computercraft.api.filesystem.IWritableMount}, it will mounted using mountWritable()
-     * @see dan200.computercraft.api.filesystem.IMount
+     * @see IMount
      * @see dan200.computercraft.api.filesystem.IWritableMount
      * @see dan200.computercraft.api.ComputerCraftAPI#createSaveDirMount(World, String, long)
      * @see dan200.computercraft.api.ComputerCraftAPI#createResourceMount(Class, String, String)

src/main/java/dan200/computercraft/api/media/IMediaProvider.java

@@ -23,7 +23,7 @@ public interface IMediaProvider
      * Produce an IMedia implementation from an ItemStack.
      *
      * @param stack The stack from which to extract the media information.
-     * @return An IMedia implementation, or null if the item is not something you wish to handle
+     * @return An {@link IMedia} implementation, or {@code null} if the item is not something you wish to handle
      * @see dan200.computercraft.api.ComputerCraftAPI#registerMediaProvider(IMediaProvider)
      */
     @Nullable

src/main/java/dan200/computercraft/api/media/package-info.java

@@ -1,10 +0,0 @@
-/*
- * This file is part of the public ComputerCraft API - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2019. This API may be redistributed unmodified and in full only.
- * For help using the API, and posting your mods, visit the forums at computercraft.info.
- */
-
-@API( owner = "ComputerCraft", provides = "ComputerCraft|API|Media", apiVersion = "${version}" )
-package dan200.computercraft.api.media;
-
-import net.minecraftforge.fml.common.API;

src/main/java/dan200/computercraft/api/network/package-info.java

@@ -1,10 +0,0 @@
-/*
- * This file is part of the public ComputerCraft API - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2019. This API may be redistributed unmodified and in full only.
- * For help using the API, and posting your mods, visit the forums at computercraft.info.
- */
-
-@API( owner = "ComputerCraft", provides = "ComputerCraft|API|Network", apiVersion = "${version}" )
-package dan200.computercraft.api.network;
-
-import net.minecraftforge.fml.common.API;

src/main/java/dan200/computercraft/api/network/wired/package-info.java

@@ -1,10 +0,0 @@
-/*
- * This file is part of the public ComputerCraft API - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2019. This API may be redistributed unmodified and in full only.
- * For help using the API, and posting your mods, visit the forums at computercraft.info.
- */
-
-@API( owner = "ComputerCraft", provides = "ComputerCraft|API|Network|Wired", apiVersion = "${version}" )
-package dan200.computercraft.api.network.wired;
-
-import net.minecraftforge.fml.common.API;

src/main/java/dan200/computercraft/api/package-info.java

@@ -1,10 +0,0 @@
-/*
- * This file is part of the public ComputerCraft API - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2019. This API may be redistributed unmodified and in full only.
- * For help using the API, and posting your mods, visit the forums at computercraft.info.
- */
-
-@API( owner = "ComputerCraft", provides = "ComputerCraft|API", apiVersion = "${version}" )
-package dan200.computercraft.api;
-
-import net.minecraftforge.fml.common.API;

src/main/java/dan200/computercraft/api/peripheral/IComputerAccess.java

@@ -9,6 +9,8 @@ package dan200.computercraft.api.peripheral;
 import dan200.computercraft.api.ComputerCraftAPI;
 import dan200.computercraft.api.filesystem.IMount;
 import dan200.computercraft.api.filesystem.IWritableMount;
+import dan200.computercraft.api.lua.ILuaContext;
+import dan200.computercraft.api.lua.ILuaTask;
 import net.minecraft.world.World;
 
 import javax.annotation.Nonnull;
@@ -146,7 +148,7 @@ public interface IComputerAccess
      *
      *                  You may supply {@code null} to indicate that no arguments are to be supplied.
      * @throws RuntimeException If the peripheral has been detached.
-     * @see dan200.computercraft.api.peripheral.IPeripheral#callMethod
+     * @see IPeripheral#callMethod
      */
     void queueEvent( @Nonnull String event, @Nullable Object[] arguments );
 
@@ -179,8 +181,8 @@ public interface IComputerAccess
     }
 
     /**
-     * Get a reachable peripheral with the given attachement name. This is a equivalent to
+     * Get a reachable peripheral with the given attachment name. This is a equivalent to
-     * {@link #getAvailablePeripherals()}{@code .get(name)}, though may be more performant.
+     * {@link #getAvailablePeripherals()}{@code .get(name)}, though may be more efficient.
      *
      * @param name The peripheral's attached name
      * @return The reachable peripheral, or {@code null} if none can be found.
@@ -191,4 +193,23 @@ public interface IComputerAccess
     {
         return null;
     }
+
+    /**
+     * Get a {@link IWorkMonitor} for tasks your peripheral might execute on the main (server) thread.
+     *
+     * This should be used to ensure your peripheral integrates with ComputerCraft's monitoring and limiting of how much
+     * server time each computer consumes. You should not need to use this if you use
+     * {@link ILuaContext#issueMainThreadTask(ILuaTask)} - this is intended for mods with their own system for running
+     * work on the main thread.
+     *
+     * Please note that the returned implementation is <em>not</em> thread-safe, and should only be used from the main
+     * thread.
+     *
+     * @return The work monitor for the main thread, or {@code null} if this computer does not have one.
+     */
+    @Nullable
+    default IWorkMonitor getMainThreadMonitor()
+    {
+        return null;
+    }
 }

src/main/java/dan200/computercraft/api/peripheral/IPeripheral.java

@@ -41,8 +41,8 @@ public interface IPeripheral
      * This is called when a lua program on an attached computer calls {@code peripheral.call()} with
      * one of the methods exposed by {@link #getMethodNames()}.
      *
-     * Be aware that this will be called from the ComputerCraft Lua thread, and must be thread-safe
+     * Be aware that this will be called from the ComputerCraft Lua thread, and must be thread-safe when interacting
-     * when interacting with Minecraft objects.
+     * with Minecraft objects.
      *
      * @param computer  The interface to the computer that is making the call. Remember that multiple
      *                  computers can be attached to a peripheral at once.
@@ -75,20 +75,21 @@ public interface IPeripheral
     Object[] callMethod( @Nonnull IComputerAccess computer, @Nonnull ILuaContext context, int method, @Nonnull Object[] arguments ) throws LuaException, InterruptedException;
 
     /**
-     * Is called when canAttachToSide has returned true, and a computer is attaching to the peripheral.
+     * Is called when when a computer is attaching to the peripheral.
      *
      * This will occur when a peripheral is placed next to an active computer, when a computer is turned on next to a
-     * peripheral, or when a turtle travels into a square next to a peripheral.
+     * peripheral, when a turtle travels into a square next to a peripheral, or when a wired modem adjacent to this
+     * peripheral is does any of the above.
      *
-     * Between calls to attach() and detach(), the attached computer can make method calls on the peripheral using
+     * Between calls to attach and {@link #detach}, the attached computer can make method calls on the peripheral using
      * {@code peripheral.call()}. This method can be used to keep track of which computers are attached to the
      * peripheral, or to take action when attachment occurs.
      *
-     * Be aware that this will be called from the ComputerCraft Lua thread, and must be thread-safe
+     * Be aware that will be called from both the server thread and ComputerCraft Lua thread, and so must be thread-safe
-     * when interacting with Minecraft objects.
+     * and reentrant.
      *
-     * @param computer The interface to the computer that is being attached. Remember that multiple
+     * @param computer The interface to the computer that is being attached. Remember that multiple computers can be
-     *                 computers can be attached to a peripheral at once.
+     *                 attached to a peripheral at once.
      * @see #detach
      */
     default void attach( @Nonnull IComputerAccess computer )
@@ -96,19 +97,21 @@ public interface IPeripheral
     }
 
     /**
-     * Is called when a computer is detaching from the peripheral.
+     * Called when a computer is detaching from the peripheral.
      *
-     * This will occur when a computer shuts down, when the peripheral is removed while attached to computers,
+     * This will occur when a computer shuts down, when the peripheral is removed while attached to computers, when a
-     * or when a turtle moves away from a square attached to a peripheral. This method can be used to keep track of
+     * turtle moves away from a block attached to a peripheral, or when a wired modem adjacent to this peripheral is
-     * which computers are attached to the peripheral, or to take action when detachment
+     * detached.
-     * occurs.
      *
-     * Be aware that this will be called from the ComputerCraft Lua thread, and must be thread-safe
+     * This method can be used to keep track of which computers are attached to the peripheral, or to take action when
-     * when interacting with Minecraft objects.
+     * detachment occurs.
      *
-     * @param computer The interface to the computer that is being detached. Remember that multiple
+     * Be aware that this will be called from both the server and ComputerCraft Lua thread, and must be thread-safe
-     *                 computers can be attached to a peripheral at once.
+     * and reentrant.
-     * @see #detach
+     *
+     * @param computer The interface to the computer that is being detached. Remember that multiple computers can be
+     *                 attached to a peripheral at once.
+     * @see #attach
      */
     default void detach( @Nonnull IComputerAccess computer )
     {

src/main/java/dan200/computercraft/api/peripheral/IPeripheralProvider.java

@@ -6,6 +6,7 @@
 
 package dan200.computercraft.api.peripheral;
 
+import net.minecraft.tileentity.TileEntity;
 import net.minecraft.util.EnumFacing;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.world.World;
@@ -16,6 +17,8 @@ import javax.annotation.Nullable;
 /**
  * This interface is used to create peripheral implementations for blocks.
  *
+ * If you have a {@link TileEntity} which acts as a peripheral, you may alternatively implement {@link IPeripheralTile}.
+ *
  * @see dan200.computercraft.api.ComputerCraftAPI#registerPeripheralProvider(IPeripheralProvider)
  */
 @FunctionalInterface

src/main/java/dan200/computercraft/api/peripheral/IPeripheralTile.java

@@ -0,0 +1,32 @@
+/*
+ * This file is part of the public ComputerCraft API - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2019. This API may be redistributed unmodified and in full only.
+ * For help using the API, and posting your mods, visit the forums at computercraft.info.
+ */
+package dan200.computercraft.api.peripheral;
+
+import net.minecraft.util.EnumFacing;
+import net.minecraft.util.math.BlockPos;
+import net.minecraft.world.World;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
+/**
+ * A {@link net.minecraft.tileentity.TileEntity} which may act as a peripheral.
+ *
+ * If you need more complex capabilities (such as handling TEs not belonging to your mod), you should use
+ * {@link IPeripheralProvider}.
+ */
+public interface IPeripheralTile
+{
+    /**
+     * Get the peripheral on the given {@code side}.
+     *
+     * @param side The side to get the peripheral from.
+     * @return A peripheral, or {@code null} if there is not a peripheral here.
+     * @see IPeripheralProvider#getPeripheral(World, BlockPos, EnumFacing)
+     */
+    @Nullable
+    IPeripheral getPeripheral( @Nonnull EnumFacing side );
+}

src/main/java/dan200/computercraft/api/peripheral/IWorkMonitor.java

@@ -0,0 +1,78 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+
+package dan200.computercraft.api.peripheral;
+
+import javax.annotation.Nonnull;
+import java.util.Objects;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * Monitors "work" associated with a computer, keeping track of how much a computer has done, and ensuring every
+ * computer receives a fair share of any processing time.
+ *
+ * This is primarily intended for work done by peripherals on the main thread (such as on a tile entity's tick), but
+ * could be used for other purposes (such as complex computations done on another thread).
+ *
+ * Before running a task, one should call {@link #canWork()} to determine if the computer is currently allowed to
+ * execute work. If that returns true, you should execute the task and use {@link #trackWork(long, TimeUnit)} to inform
+ * the monitor how long that task took.
+ *
+ * Alternatively, use {@link #runWork(Runnable)} to run and keep track of work.
+ *
+ * @see IComputerAccess#getMainThreadMonitor()
+ */
+public interface IWorkMonitor
+{
+    /**
+     * If the owning computer is currently allowed to execute work.
+     *
+     * @return If we can execute work right now.
+     */
+    boolean canWork();
+
+    /**
+     * If the owning computer is currently allowed to execute work, and has ample time to do so.
+     *
+     * This is effectively a more restrictive form of {@link #canWork()}. One should use that in order to determine if
+     * you may do an initial piece of work, and shouldWork to determine if any additional task may be performed.
+     *
+     * @return If we should execute work right now.
+     */
+    boolean shouldWork();
+
+    /**
+     * Inform the monitor how long some piece of work took to execute.
+     *
+     * @param time The time some task took to run
+     * @param unit The unit that {@code time} was measured in.
+     */
+    void trackWork( long time, @Nonnull TimeUnit unit );
+
+    /**
+     * Run a task if possible, and inform the monitor of how long it took.
+     *
+     * @param runnable The task to run.
+     * @return If the task was actually run (namely, {@link #canWork()} returned {@code true}).
+     */
+    default boolean runWork( @Nonnull Runnable runnable )
+    {
+        Objects.requireNonNull( runnable, "runnable should not be null" );
+        if( !canWork() ) return false;
+
+        long start = System.nanoTime();
+        try
+        {
+            runnable.run();
+        }
+        finally
+        {
+            trackWork( System.nanoTime() - start, TimeUnit.NANOSECONDS );
+        }
+
+        return true;
+    }
+}

src/main/java/dan200/computercraft/api/peripheral/package-info.java

@@ -1,10 +0,0 @@
-/*
- * This file is part of the public ComputerCraft API - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2019. This API may be redistributed unmodified and in full only.
- * For help using the API, and posting your mods, visit the forums at computercraft.info.
- */
-
-@API( owner = "ComputerCraft", provides = "ComputerCraft|API|Peripheral", apiVersion = "${version}" )
-package dan200.computercraft.api.peripheral;
-
-import net.minecraftforge.fml.common.API;

src/main/java/dan200/computercraft/api/permissions/ITurtlePermissionProvider.java

@@ -1,42 +0,0 @@
-/*
- * This file is part of the public ComputerCraft API - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2019. This API may be redistributed unmodified and in full only.
- * For help using the API, and posting your mods, visit the forums at computercraft.info.
- */
-
-package dan200.computercraft.api.permissions;
-
-import net.minecraft.util.math.BlockPos;
-import net.minecraft.world.World;
-
-import javax.annotation.Nonnull;
-
-/**
- * This interface is used to restrict where turtles can move or build.
- *
- * Turtles will call these methods before attempting to perform an action, allowing them to be cancelled.
- *
- * @see dan200.computercraft.api.ComputerCraftAPI#registerPermissionProvider(ITurtlePermissionProvider)
- */
-public interface ITurtlePermissionProvider
-{
-    /**
-     * Determine whether a block can be entered by a turtle.
-     *
-     * @param world The world the block exists in
-     * @param pos   The location of the block.
-     * @return Whether the turtle can move into this block.
-     */
-    boolean isBlockEnterable( @Nonnull World world, @Nonnull BlockPos pos );
-
-    /**
-     * Determine whether a block can be modified by a turtle.
-     *
-     * This includes breaking and placing blocks.
-     *
-     * @param world The world the block exists in
-     * @param pos   The location of the block.
-     * @return Whether the turtle can modify this block.
-     */
-    boolean isBlockEditable( @Nonnull World world, @Nonnull BlockPos pos );
-}

src/main/java/dan200/computercraft/api/permissions/package-info.java

@@ -1,10 +0,0 @@
-/*
- * This file is part of the public ComputerCraft API - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2019. This API may be redistributed unmodified and in full only.
- * For help using the API, and posting your mods, visit the forums at computercraft.info.
- */
-
-@API( owner = "ComputerCraft", provides = "ComputerCraft|API|Permissions", apiVersion = "${version}" )
-package dan200.computercraft.api.permissions;
-
-import net.minecraftforge.fml.common.API;

src/main/java/dan200/computercraft/api/pocket/AbstractPocketUpgrade.java

@@ -4,14 +4,20 @@
  * Send enquiries to dratcliffe@gmail.com
  */
 
-package dan200.computercraft.shared.pocket.peripherals;
+package dan200.computercraft.api.pocket;
 
-import dan200.computercraft.api.pocket.IPocketUpgrade;
 import net.minecraft.item.ItemStack;
+import net.minecraft.util.IItemProvider;
 import net.minecraft.util.ResourceLocation;
+import net.minecraft.util.Util;
 
 import javax.annotation.Nonnull;
 
+/**
+ * A base class for {@link IPocketUpgrade}s.
+ *
+ * One does not have to use this, but it does provide a convenient template.
+ */
 public abstract class AbstractPocketUpgrade implements IPocketUpgrade
 {
     private final ResourceLocation id;
@@ -25,9 +31,14 @@ public abstract class AbstractPocketUpgrade implements IPocketUpgrade
         this.stack = stack;
     }
 
-    protected AbstractPocketUpgrade( ResourceLocation id, ItemStack stack )
+    protected AbstractPocketUpgrade( ResourceLocation id, String adjective, IItemProvider item )
     {
-        this( id, "upgrade." + id + ".adjective", stack );
+        this( id, adjective, new ItemStack( item ) );
+    }
+
+    protected AbstractPocketUpgrade( ResourceLocation id, IItemProvider item )
+    {
+        this( id, Util.makeTranslationKey( "upgrade", id ) + ".adjective", new ItemStack( item ) );
     }
 
     @Nonnull

src/main/java/dan200/computercraft/api/pocket/IPocketAccess.java

@@ -23,7 +23,9 @@ public interface IPocketAccess
     /**
      * Gets the entity holding this item.
      *
-     * @return The holding entity. This may be {@code null}.
+     * This must be called on the server thread.
+     *
+     * @return The holding entity, or {@code null} if none exists.
      */
     @Nullable
     Entity getEntity();

src/main/java/dan200/computercraft/api/pocket/IPocketUpgrade.java

@@ -19,7 +19,7 @@ import javax.annotation.Nullable;
 /**
  * Additional peripherals for pocket computers.
  *
- * This is similar to {@link dan200.computercraft.api.turtle.ITurtleUpgrade}.
+ * This is similar to {@link ITurtleUpgrade}.
  */
 public interface IPocketUpgrade
 {
@@ -54,6 +54,9 @@ public interface IPocketUpgrade
      * pocket computer which holds this upgrade. This item stack is also used to determine the upgrade given by
      * {@code pocket.equip()}/{@code pocket.unequip()}.
      *
+     * Ideally this should be constant over a session. It is recommended that you cache
+     * the item too, in order to prevent constructing it every time the method is called.
+     *
      * @return The item stack used for crafting. This can be {@link ItemStack#EMPTY} if crafting is disabled.
      */
     @Nonnull

src/main/java/dan200/computercraft/api/redstone/package-info.java

@@ -1,10 +0,0 @@
-/*
- * This file is part of the public ComputerCraft API - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2019. This API may be redistributed unmodified and in full only.
- * For help using the API, and posting your mods, visit the forums at computercraft.info.
- */
-
-@API( owner = "ComputerCraft", provides = "ComputerCraft|API|Redstone", apiVersion = "${version}" )
-package dan200.computercraft.api.redstone;
-
-import net.minecraftforge.fml.common.API;

src/main/java/dan200/computercraft/api/turtle/ITurtleAccess.java

@@ -54,8 +54,7 @@ public interface ITurtleAccess
      * @param world The new world to move it to
      * @param pos   The new position to move it to.
      * @return Whether the movement was successful. It may fail if the block was not loaded or the block placement
-     * was cancelled. Note this will not check
+     * was cancelled.
-     * {@link dan200.computercraft.api.permissions.ITurtlePermissionProvider#isBlockEnterable(World, BlockPos)}.
      * @throws UnsupportedOperationException When attempting to teleport on the client side.
      */
     boolean teleportTo( @Nonnull World world, @Nonnull BlockPos pos );

src/main/java/dan200/computercraft/api/turtle/ITurtleUpgrade.java

@@ -10,15 +10,15 @@ import dan200.computercraft.api.ComputerCraftAPI;
 import dan200.computercraft.api.peripheral.IPeripheral;
 import dan200.computercraft.api.turtle.event.TurtleAttackEvent;
 import dan200.computercraft.api.turtle.event.TurtleBlockEvent;
-import net.minecraft.client.renderer.block.model.IBakedModel;
+import net.minecraft.client.renderer.model.IBakedModel;
-import net.minecraft.client.renderer.block.model.ModelResourceLocation;
+import net.minecraft.client.renderer.model.ModelResourceLocation;
 import net.minecraft.item.ItemStack;
 import net.minecraft.util.EnumFacing;
 import net.minecraft.util.ResourceLocation;
+import net.minecraftforge.api.distmarker.Dist;
+import net.minecraftforge.api.distmarker.OnlyIn;
 import net.minecraftforge.event.entity.player.AttackEntityEvent;
 import net.minecraftforge.event.world.BlockEvent;
-import net.minecraftforge.fml.relauncher.Side;
-import net.minecraftforge.fml.relauncher.SideOnly;
 import org.apache.commons.lang3.tuple.Pair;
 
 import javax.annotation.Nonnull;
@@ -44,17 +44,6 @@ public interface ITurtleUpgrade
     @Nonnull
     ResourceLocation getUpgradeID();
 
-    /**
-     * Gets a numerical identifier representing this type of turtle upgrade,
-     * for backwards compatibility with pre-1.76 worlds. If your upgrade was
-     * not released for older ComputerCraft versions, you can return -1 here.
-     * The turtle will fail registration if an already used positive ID is specified.
-     *
-     * @return The legacy ID, or -1 if is needed.
-     * @see ComputerCraftAPI#registerTurtleUpgrade(ITurtleUpgrade)
-     */
-    int getLegacyUpgradeID();
-
     /**
      * Return an unlocalised string to describe this type of turtle in turtle item names.
      *
@@ -79,6 +68,9 @@ public interface ITurtleUpgrade
      * with to create a turtle which holds this upgrade. This item stack is also used
      * to determine the upgrade given by {@code turtle.equip()}
      *
+     * Ideally this should be constant over a session. It is recommended that you cache
+     * the item too, in order to prevent constructing it every time the method is called.
+     *
      * @return The item stack to craft with, or {@link ItemStack#EMPTY} if it cannot be crafted.
      */
     @Nonnull
@@ -130,7 +122,7 @@ public interface ITurtleUpgrade
      * Called to obtain the model to be used when rendering a turtle peripheral.
      *
      * This can be obtained from {@link net.minecraft.client.renderer.ItemModelMesher#getItemModel(ItemStack)},
-     * {@link net.minecraft.client.renderer.block.model.ModelManager#getModel(ModelResourceLocation)} or any other
+     * {@link net.minecraft.client.renderer.model.ModelManager#getModel(ModelResourceLocation)} or any other
      * source.
      *
      * @param turtle Access to the turtle that the upgrade resides on. This will be null when getting item models!
@@ -139,7 +131,7 @@ public interface ITurtleUpgrade
      * a transformation of {@code null} has the same effect as the identify matrix.
      */
     @Nonnull
-    @SideOnly( Side.CLIENT )
+    @OnlyIn( Dist.CLIENT )
     Pair<IBakedModel, Matrix4f> getModel( @Nullable ITurtleAccess turtle, @Nonnull TurtleSide side );
 
     /**

src/main/java/dan200/computercraft/api/turtle/event/TurtleActionEvent.java

@@ -8,7 +8,7 @@ package dan200.computercraft.api.turtle.event;
 
 import dan200.computercraft.api.turtle.ITurtleAccess;
 import dan200.computercraft.api.turtle.TurtleCommandResult;
-import net.minecraftforge.fml.common.eventhandler.Cancelable;
+import net.minecraftforge.eventbus.api.Cancelable;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;

src/main/java/dan200/computercraft/api/turtle/event/TurtleBlockEvent.java

@@ -19,7 +19,6 @@ import net.minecraft.util.math.BlockPos;
 import net.minecraft.world.World;
 import net.minecraftforge.common.util.FakePlayer;
 import net.minecraftforge.event.world.BlockEvent;
-import net.minecraftforge.fml.common.eventhandler.Cancelable;
 
 import javax.annotation.Nonnull;
 import java.util.Map;
@@ -37,7 +36,6 @@ import java.util.Objects;
  * Be aware that some events (such as {@link TurtleInventoryEvent}) do not necessarily interact
  * with a block, simply objects within that block space.
  */
-@Cancelable
 public abstract class TurtleBlockEvent extends TurtlePlayerEvent
 {
     private final World world;
@@ -84,7 +82,6 @@ public abstract class TurtleBlockEvent extends TurtlePlayerEvent
      *
      * @see TurtleAction#DIG
      */
-    @Cancelable
     public static class Dig extends TurtleBlockEvent
     {
         private final IBlockState block;
@@ -142,7 +139,6 @@ public abstract class TurtleBlockEvent extends TurtlePlayerEvent
      *
      * @see TurtleAction#MOVE
      */
-    @Cancelable
     public static class Move extends TurtleBlockEvent
     {
         public Move( @Nonnull ITurtleAccess turtle, @Nonnull FakePlayer player, @Nonnull World world, @Nonnull BlockPos pos )
@@ -156,7 +152,6 @@ public abstract class TurtleBlockEvent extends TurtlePlayerEvent
      *
      * @see TurtleAction#PLACE
      */
-    @Cancelable
     public static class Place extends TurtleBlockEvent
     {
         private final ItemStack stack;
@@ -188,7 +183,6 @@ public abstract class TurtleBlockEvent extends TurtlePlayerEvent
      *
      * @see TurtleAction#INSPECT
      */
-    @Cancelable
     public static class Inspect extends TurtleBlockEvent
     {
         private final IBlockState state;
@@ -229,7 +223,7 @@ public abstract class TurtleBlockEvent extends TurtlePlayerEvent
         /**
          * Add new information to the inspection result. Note this will override fields with the same name.
          *
-         * @param newData The data to add. Note all values should be convertable to Lua (see
+         * @param newData The data to add. Note all values should be convertible to Lua (see
          *                {@link dan200.computercraft.api.peripheral.IPeripheral#callMethod(IComputerAccess, ILuaContext, int, Object[])}).
          */
         public void addData( @Nonnull Map<String, ?> newData )

src/main/java/dan200/computercraft/api/turtle/event/TurtleEvent.java

@@ -7,7 +7,7 @@
 package dan200.computercraft.api.turtle.event;
 
 import dan200.computercraft.api.turtle.ITurtleAccess;
-import net.minecraftforge.fml.common.eventhandler.Event;
+import net.minecraftforge.eventbus.api.Event;
 
 import javax.annotation.Nonnull;
 import java.util.Objects;

src/main/java/dan200/computercraft/api/turtle/event/TurtleInspectItemEvent.java

@@ -0,0 +1,74 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+
+package dan200.computercraft.api.turtle.event;
+
+import dan200.computercraft.api.lua.ILuaContext;
+import dan200.computercraft.api.peripheral.IComputerAccess;
+import dan200.computercraft.api.turtle.ITurtleAccess;
+import net.minecraft.item.ItemStack;
+
+import javax.annotation.Nonnull;
+import java.util.Map;
+import java.util.Objects;
+
+/**
+ * Fired when a turtle gathers data on an item in its inventory.
+ *
+ * You may prevent items being inspected, or add additional information to the result. Be aware that this is fired on
+ * the computer thread, and so any operations on it must be thread safe.
+ *
+ * @see TurtleAction#INSPECT_ITEM
+ */
+public class TurtleInspectItemEvent extends TurtleActionEvent
+{
+    private final ItemStack stack;
+    private final Map<String, Object> data;
+
+    public TurtleInspectItemEvent( @Nonnull ITurtleAccess turtle, @Nonnull ItemStack stack, @Nonnull Map<String, Object> data )
+    {
+        super( turtle, TurtleAction.INSPECT_ITEM );
+
+        Objects.requireNonNull( stack, "stack cannot be null" );
+        Objects.requireNonNull( data, "data cannot be null" );
+        this.stack = stack;
+        this.data = data;
+    }
+
+    /**
+     * The item which is currently being inspected.
+     *
+     * @return The item stack which is being inspected. This should <b>not</b> be modified.
+     */
+    @Nonnull
+    public ItemStack getStack()
+    {
+        return stack;
+    }
+
+    /**
+     * Get the "inspection data" from this item, which will be returned to the user.
+     *
+     * @return This items's inspection data.
+     */
+    @Nonnull
+    public Map<String, Object> getData()
+    {
+        return data;
+    }
+
+    /**
+     * Add new information to the inspection result. Note this will override fields with the same name.
+     *
+     * @param newData The data to add. Note all values should be convertible to Lua (see
+     *                {@link dan200.computercraft.api.peripheral.IPeripheral#callMethod(IComputerAccess, ILuaContext, int, Object[])}).
+     */
+    public void addData( @Nonnull Map<String, ?> newData )
+    {
+        Objects.requireNonNull( newData, "newData cannot be null" );
+        data.putAll( newData );
+    }
+}

src/main/java/dan200/computercraft/api/turtle/event/TurtleInventoryEvent.java

@@ -11,7 +11,6 @@ import net.minecraft.item.ItemStack;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.world.World;
 import net.minecraftforge.common.util.FakePlayer;
-import net.minecraftforge.fml.common.eventhandler.Cancelable;
 import net.minecraftforge.items.IItemHandler;
 
 import javax.annotation.Nonnull;
@@ -21,7 +20,6 @@ import java.util.Objects;
 /**
  * Fired when a turtle attempts to interact with an inventory.
  */
-@Cancelable
 public abstract class TurtleInventoryEvent extends TurtleBlockEvent
 {
     private final IItemHandler handler;
@@ -48,7 +46,6 @@ public abstract class TurtleInventoryEvent extends TurtleBlockEvent
      *
      * @see TurtleAction#SUCK
      */
-    @Cancelable
     public static class Suck extends TurtleInventoryEvent
     {
         public Suck( @Nonnull ITurtleAccess turtle, @Nonnull FakePlayer player, @Nonnull World world, @Nonnull BlockPos pos, @Nullable IItemHandler handler )
@@ -62,7 +59,6 @@ public abstract class TurtleInventoryEvent extends TurtleBlockEvent
      *
      * @see TurtleAction#DROP
      */
-    @Cancelable
     public static class Drop extends TurtleInventoryEvent
     {
         private final ItemStack stack;
@@ -78,13 +74,12 @@ public abstract class TurtleInventoryEvent extends TurtleBlockEvent
         /**
          * The item which will be inserted into the inventory/dropped on the ground.
          *
-         * Note that this is a copy of the original stack, and so should not be modified, as that will have no effect.
+         * @return The item stack which will be dropped. This should <b>not</b> be modified.
-         *
-         * @return The item stack which will be dropped.
          */
+        @Nonnull
         public ItemStack getStack()
         {
-            return stack.copy();
+            return stack;
         }
     }
 }

src/main/java/dan200/computercraft/api/turtle/event/TurtleRefuelEvent.java

@@ -0,0 +1,91 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+
+package dan200.computercraft.api.turtle.event;
+
+import dan200.computercraft.api.turtle.ITurtleAccess;
+import net.minecraft.item.ItemStack;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+import java.util.Objects;
+
+/**
+ * Fired when a turtle attempts to refuel from an item.
+ *
+ * One may use {@link #setCanceled(boolean, String)} to prevent refueling from this specific item. Additionally, you
+ * may use {@link #setHandler(Handler)} to register a custom fuel provider.
+ */
+public class TurtleRefuelEvent extends TurtleActionEvent
+{
+    private final ItemStack stack;
+    private Handler handler;
+
+    public TurtleRefuelEvent( @Nonnull ITurtleAccess turtle, @Nonnull ItemStack stack )
+    {
+        super( turtle, TurtleAction.REFUEL );
+
+        Objects.requireNonNull( turtle, "turtle cannot be null" );
+        this.stack = stack;
+    }
+
+    /**
+     * Get the stack we are attempting to refuel from.
+     *
+     * Do not modify the returned stack - all modifications should be done within the {@link Handler}.
+     *
+     * @return The stack to refuel from.
+     */
+    public ItemStack getStack()
+    {
+        return stack;
+    }
+
+    /**
+     * Get the refuel handler for this stack.
+     *
+     * @return The refuel handler, or {@code null} if none has currently been set.
+     * @see #setHandler(Handler)
+     */
+    @Nullable
+    public Handler getHandler()
+    {
+        return handler;
+    }
+
+    /**
+     * Set the refuel handler for this stack.
+     *
+     * You should call this if you can actually refuel from this item, and ideally only if there are no existing
+     * handlers.
+     *
+     * @param handler The new refuel handler.
+     * @see #getHandler()
+     */
+    public void setHandler( @Nullable Handler handler )
+    {
+        this.handler = handler;
+    }
+
+    /**
+     * Handles refuelling a turtle from a specific item.
+     */
+    @FunctionalInterface
+    public interface Handler
+    {
+        /**
+         * Refuel a turtle using an item.
+         *
+         * @param turtle The turtle to refuel.
+         * @param stack  The stack to refuel with.
+         * @param slot   The slot the stack resides within. This may be used to modify the inventory afterwards.
+         * @param limit  The maximum number of refuel operations to perform. This will often correspond to the number of
+         *               items to consume.
+         * @return The amount of fuel gained.
+         */
+        int refuel( @Nonnull ITurtleAccess turtle, @Nonnull ItemStack stack, int slot, int limit );
+    }
+}

src/main/java/dan200/computercraft/api/turtle/event/package-info.java

@@ -1,10 +0,0 @@
-/*
- * This file is part of the public ComputerCraft API - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2019. This API may be redistributed unmodified and in full only.
- * For help using the API, and posting your mods, visit the forums at computercraft.info.
- */
-
-@API( owner = "ComputerCraft", provides = "ComputerCraft|API|Turtle|Event", apiVersion = "${version}" )
-package dan200.computercraft.api.turtle.event;
-
-import net.minecraftforge.fml.common.API;

src/main/java/dan200/computercraft/api/turtle/package-info.java

@@ -1,10 +0,0 @@
-/*
- * This file is part of the public ComputerCraft API - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2019. This API may be redistributed unmodified and in full only.
- * For help using the API, and posting your mods, visit the forums at computercraft.info.
- */
-
-@API( owner = "ComputerCraft", provides = "ComputerCraft|API|Turtle", apiVersion = "${version}" )
-package dan200.computercraft.api.turtle;
-
-import net.minecraftforge.fml.common.API;

src/main/java/dan200/computercraft/client/ClientRegistry.java

@@ -8,101 +8,81 @@ package dan200.computercraft.client;
 
 import dan200.computercraft.ComputerCraft;
 import dan200.computercraft.client.render.TurtleModelLoader;
-import dan200.computercraft.shared.media.items.ItemDiskLegacy;
+import dan200.computercraft.shared.common.IColouredItem;
-import dan200.computercraft.shared.turtle.items.ItemTurtleBase;
+import dan200.computercraft.shared.media.items.ItemDisk;
+import dan200.computercraft.shared.pocket.items.ItemPocketComputer;
 import dan200.computercraft.shared.util.Colour;
 import net.minecraft.client.Minecraft;
-import net.minecraft.client.renderer.ItemMeshDefinition;
+import net.minecraft.client.renderer.model.IBakedModel;
-import net.minecraft.client.renderer.block.model.IBakedModel;
+import net.minecraft.client.renderer.model.IUnbakedModel;
-import net.minecraft.client.renderer.block.model.ModelBakery;
+import net.minecraft.client.renderer.model.ModelResourceLocation;
-import net.minecraft.client.renderer.block.model.ModelResourceLocation;
+import net.minecraft.client.renderer.model.ModelRotation;
-import net.minecraft.client.renderer.texture.TextureMap;
 import net.minecraft.client.renderer.vertex.DefaultVertexFormats;
-import net.minecraft.item.Item;
+import net.minecraft.resources.IResourceManager;
-import net.minecraft.item.ItemStack;
 import net.minecraft.util.ResourceLocation;
+import net.minecraftforge.api.distmarker.Dist;
 import net.minecraftforge.client.event.ColorHandlerEvent;
 import net.minecraftforge.client.event.ModelBakeEvent;
 import net.minecraftforge.client.event.ModelRegistryEvent;
 import net.minecraftforge.client.event.TextureStitchEvent;
-import net.minecraftforge.client.model.IModel;
 import net.minecraftforge.client.model.ModelLoader;
 import net.minecraftforge.client.model.ModelLoaderRegistry;
+import net.minecraftforge.eventbus.api.SubscribeEvent;
 import net.minecraftforge.fml.common.Mod;
-import net.minecraftforge.fml.common.eventhandler.SubscribeEvent;
-import net.minecraftforge.fml.relauncher.Side;
 
-import javax.annotation.Nonnull;
+import java.util.HashSet;
+import java.util.Map;
 
 /**
  * Registers textures and models for items.
  */
-@Mod.EventBusSubscriber( modid = ComputerCraft.MOD_ID, value = Side.CLIENT )
+@Mod.EventBusSubscriber( modid = ComputerCraft.MOD_ID, value = Dist.CLIENT )
-public class ClientRegistry
+public final class ClientRegistry
 {
-    private static final String[] EXTRA_MODELS = {
+    private static final String[] EXTRA_MODELS = new String[] {
-        "turtle_modem_off_left",
+        "turtle_modem_normal_off_left",
-        "turtle_modem_on_left",
+        "turtle_modem_normal_on_left",
-        "turtle_modem_off_right",
+        "turtle_modem_normal_off_right",
-        "turtle_modem_on_right",
+        "turtle_modem_normal_on_right",
+
+        "turtle_modem_advanced_off_left",
+        "turtle_modem_advanced_on_left",
+        "turtle_modem_advanced_off_right",
+        "turtle_modem_advanced_on_right",
         "turtle_crafting_table_left",
         "turtle_crafting_table_right",
-        "advanced_turtle_modem_off_left",
+
-        "advanced_turtle_modem_on_left",
-        "advanced_turtle_modem_off_right",
-        "advanced_turtle_modem_on_right",
         "turtle_speaker_upgrade_left",
         "turtle_speaker_upgrade_right",
 
-        "turtle_white",
+        "turtle_colour",
         "turtle_elf_overlay",
     };
 
+    private static final String[] EXTRA_TEXTURES = new String[] {
+        // TODO: Gather these automatically from the model. I'm unable to get this working with Forge's current
+        //  model loading code.
+        "block/turtle_colour",
+        "block/turtle_elf_overlay",
+        "block/turtle_crafty_face",
+        "block/turtle_speaker_face",
+    };
+
+    private ClientRegistry() {}
+
     @SubscribeEvent
     public static void registerModels( ModelRegistryEvent event )
     {
         ModelLoaderRegistry.registerLoader( TurtleModelLoader.INSTANCE );
-
-        // Register item models
-        registerUniversalItemModel( ComputerCraft.Items.computer, "computer" );
-        registerItemModel( ComputerCraft.Items.commandComputer, 0, "command_computer" );
-
-        registerItemModel( ComputerCraft.Items.pocketComputer, 0, "pocket_computer" );
-        registerItemModel( ComputerCraft.Items.pocketComputer, 1, "advanced_pocket_computer" );
-
-        registerItemModel( ComputerCraft.Items.peripheral, 0, "peripheral" );
-        registerItemModel( ComputerCraft.Items.peripheral, 1, "wireless_modem" );
-        registerItemModel( ComputerCraft.Items.peripheral, 2, "monitor" );
-        registerItemModel( ComputerCraft.Items.peripheral, 3, "printer" );
-        registerItemModel( ComputerCraft.Items.peripheral, 4, "advanced_monitor" );
-        registerItemModel( ComputerCraft.Items.cable, 0, "cable" );
-        registerItemModel( ComputerCraft.Items.cable, 1, "wired_modem" );
-        registerItemModel( ComputerCraft.Items.advancedModem, 0, "advanced_modem" );
-        registerItemModel( ComputerCraft.Items.peripheral, 5, "speaker" );
-        registerItemModel( ComputerCraft.Items.wiredModemFull, 0, "wired_modem_full" );
-
-        registerUniversalItemModel( ComputerCraft.Items.disk, "disk" );
-        registerItemModel( ComputerCraft.Items.diskExpanded, 0, "disk_expanded" );
-        registerItemModel( ComputerCraft.Items.treasureDisk, 0, "treasure_disk" );
-
-        registerItemModel( ComputerCraft.Items.printout, 0, "printout" );
-        registerItemModel( ComputerCraft.Items.printout, 1, "pages" );
-        registerItemModel( ComputerCraft.Items.printout, 2, "book" );
-
-        registerUniversalItemModel( ComputerCraft.Items.turtle, "turtle" );
-        registerUniversalItemModel( ComputerCraft.Items.turtleExpanded, "turtle" );
-        registerUniversalItemModel( ComputerCraft.Items.turtleAdvanced, "turtle_advanced" );
     }
 
     @SubscribeEvent
     public static void onTextureStitchEvent( TextureStitchEvent.Pre event )
     {
-        // Load all textures for the extra models
+        IResourceManager manager = Minecraft.getInstance().getResourceManager();
-        TextureMap map = event.getMap();
+        for( String extra : EXTRA_TEXTURES )
-        for( String upgrade : EXTRA_MODELS )
         {
-            IModel model = ModelLoaderRegistry.getModelOrMissing( new ResourceLocation( "computercraft", "block/" + upgrade ) );
+            event.getMap().registerSprite( manager, new ResourceLocation( ComputerCraft.MOD_ID, extra ) );
-            for( ResourceLocation texture : model.getTextures() ) map.registerSprite( texture );
         }
     }
 
@@ -110,84 +90,79 @@ public class ClientRegistry
     public static void onModelBakeEvent( ModelBakeEvent event )
     {
         // Load all extra models
-        for( String model : EXTRA_MODELS ) loadBlockModel( event, model );
+        ModelLoader loader = event.getModelLoader();
+        Map<ModelResourceLocation, IBakedModel> registry = event.getModelRegistry();
+
+        for( String model : EXTRA_MODELS )
+        {
+            IBakedModel bakedModel = bake( loader, loader.getUnbakedModel( new ResourceLocation( ComputerCraft.MOD_ID, "item/" + model ) ) );
+
+            if( bakedModel != null )
+            {
+                registry.put(
+                    new ModelResourceLocation( new ResourceLocation( ComputerCraft.MOD_ID, model ), "inventory" ),
+                    bakedModel
+                );
+            }
+        }
+
+        // And load the custom turtle models in too.
+        registry.put(
+            new ModelResourceLocation( new ResourceLocation( ComputerCraft.MOD_ID, "turtle_normal" ), "inventory" ),
+            bake( loader, TurtleModelLoader.INSTANCE.loadModel( new ResourceLocation( ComputerCraft.MOD_ID, "item/turtle_normal" ) ) )
+        );
+
+        registry.put(
+            new ModelResourceLocation( new ResourceLocation( ComputerCraft.MOD_ID, "turtle_advanced" ), "inventory" ),
+            bake( loader, TurtleModelLoader.INSTANCE.loadModel( new ResourceLocation( ComputerCraft.MOD_ID, "item/turtle_advanced" ) ) )
+        );
     }
 
     @SubscribeEvent
     public static void onItemColours( ColorHandlerEvent.Item event )
     {
-        event.getItemColors().registerItemColorHandler(
+        if( ComputerCraft.Items.disk == null || ComputerCraft.Blocks.turtleNormal == null )
-            ( stack, layer ) -> layer == 0 ? 0xFFFFFF : ((ItemDiskLegacy) stack.getItem()).getColour( stack ),
+        {
-            ComputerCraft.Items.disk, ComputerCraft.Items.diskExpanded
+            ComputerCraft.log.warn( "Block/item registration has failed. Skipping registration of item colours." );
+            return;
+        }
+
+        event.getItemColors().register(
+            ( stack, layer ) -> layer == 1 ? ((ItemDisk) stack.getItem()).getColour( stack ) : 0xFFFFFF,
+            ComputerCraft.Items.disk
         );
 
-        event.getItemColors().registerItemColorHandler( ( stack, layer ) -> {
+        event.getItemColors().register( ( stack, layer ) -> {
             switch( layer )
             {
                 case 0:
                 default:
                     return 0xFFFFFF;
-                case 1:
+                case 1: // Frame colour
+                    return IColouredItem.getColourBasic( stack );
+                case 2: // Light colour
                 {
-                    // Frame colour
+                    int light = ItemPocketComputer.getLightState( stack );
-                    int colour = ComputerCraft.Items.pocketComputer.getColour( stack );
+                    return light == -1 ? Colour.Black.getHex() : light;
-                    return colour == -1 ? 0xFFFFFF : colour;
-                }
-                case 2:
-                {
-                    // Light colour
-                    int colour = ComputerCraft.Items.pocketComputer.getLightState( stack );
-                    return colour == -1 ? Colour.Black.getHex() : colour;
                 }
             }
-        }, ComputerCraft.Items.pocketComputer );
+        }, ComputerCraft.Items.pocketComputerNormal, ComputerCraft.Items.pocketComputerAdvanced );
 
         // Setup turtle colours
-        event.getItemColors().registerItemColorHandler( ( stack, tintIndex ) -> {
+        event.getItemColors().register(
-            if( tintIndex == 0 )
+            ( stack, tintIndex ) -> tintIndex == 0 ? ((IColouredItem) stack.getItem()).getColour( stack ) : 0xFFFFFF,
-            {
+            ComputerCraft.Blocks.turtleNormal, ComputerCraft.Blocks.turtleAdvanced
-                ItemTurtleBase turtle = (ItemTurtleBase) stack.getItem();
-                int colour = turtle.getColour( stack );
-                if( colour != -1 ) return colour;
-            }
-
-            return 0xFFFFFF;
-        }, ComputerCraft.Blocks.turtle, ComputerCraft.Blocks.turtleExpanded, ComputerCraft.Blocks.turtleAdvanced );
-    }
-
-    private static void registerItemModel( Item item, int damage, String name )
-    {
-        ResourceLocation location = new ResourceLocation( ComputerCraft.MOD_ID, name );
-        final ModelResourceLocation res = new ModelResourceLocation( location, "inventory" );
-        ModelBakery.registerItemVariants( item, location );
-        ModelLoader.setCustomModelResourceLocation( item, damage, res );
-    }
-
-    private static void registerUniversalItemModel( Item item, String mainModel )
-    {
-        ResourceLocation mainLocation = new ResourceLocation( ComputerCraft.MOD_ID, mainModel );
-        ModelBakery.registerItemVariants( item, mainLocation );
-
-        final ModelResourceLocation mainModelLocation = new ModelResourceLocation( mainLocation, "inventory" );
-        ModelLoader.setCustomMeshDefinition( item, new ItemMeshDefinition()
-        {
-            @Nonnull
-            @Override
-            public ModelResourceLocation getModelLocation( @Nonnull ItemStack stack )
-            {
-                return mainModelLocation;
-            }
-        } );
-    }
-
-    private static void loadBlockModel( ModelBakeEvent event, String name )
-    {
-        IModel model = ModelLoaderRegistry.getModelOrMissing( new ResourceLocation( ComputerCraft.MOD_ID, "block/" + name ) );
-        IBakedModel bakedModel = model.bake(
-            model.getDefaultState(), DefaultVertexFormats.ITEM,
-            location -> Minecraft.getMinecraft().getTextureMapBlocks().getAtlasSprite( location.toString() )
         );
+    }
 
-        event.getModelRegistry().putObject( new ModelResourceLocation( ComputerCraft.MOD_ID + ":" + name, "inventory" ), bakedModel );
+    private static IBakedModel bake( ModelLoader loader, IUnbakedModel model )
+    {
+        model.getTextures( loader::getUnbakedModel, new HashSet<>() );
+
+        return model.bake(
+            loader::getUnbakedModel,
+            ModelLoader.defaultTextureGetter(),
+            ModelRotation.X0_Y0, false, DefaultVertexFormats.BLOCK
+        );
     }
 }

src/main/java/dan200/computercraft/client/ClientTableFormatter.java

@@ -28,9 +28,9 @@ public class ClientTableFormatter implements TableFormatter
 
     private static Int2IntOpenHashMap lastHeights = new Int2IntOpenHashMap();
 
-    private FontRenderer renderer()
+    private static FontRenderer renderer()
     {
-        return Minecraft.getMinecraft().fontRenderer;
+        return Minecraft.getInstance().fontRenderer;
     }
 
     @Override
@@ -42,7 +42,7 @@ public class ClientTableFormatter implements TableFormatter
 
         FontRenderer renderer = renderer();
 
-        float spaceWidth = renderer.getCharWidth( ' ' );
+        float spaceWidth = renderer.getStringWidth( " " );
         int spaces = MathHelper.floor( extraWidth / spaceWidth );
         int extra = extraWidth - (int) (spaces * spaceWidth);
 
@@ -64,11 +64,11 @@ public class ClientTableFormatter implements TableFormatter
     @Override
     public void writeLine( int id, ITextComponent component )
     {
-        Minecraft mc = Minecraft.getMinecraft();
+        Minecraft mc = Minecraft.getInstance();
         GuiNewChat chat = mc.ingameGUI.getChatGUI();
 
         // Trim the text if it goes over the allowed length
-        int maxWidth = MathHelper.floor( chat.getChatWidth() / chat.getChatScale() );
+        int maxWidth = MathHelper.floor( chat.getChatWidth() / chat.getScale() );
         List<ITextComponent> list = GuiUtilRenderComponents.splitText( component, maxWidth, mc.fontRenderer, false, false );
         if( !list.isEmpty() ) chat.printChatMessageWithOptionalDeletion( list.get( 0 ), id );
     }
@@ -76,7 +76,7 @@ public class ClientTableFormatter implements TableFormatter
     @Override
     public int display( TableBuilder table )
     {
-        GuiNewChat chat = Minecraft.getMinecraft().ingameGUI.getChatGUI();
+        GuiNewChat chat = Minecraft.getInstance().ingameGUI.getChatGUI();
 
         int lastHeight = lastHeights.get( table.getId() );
 

src/main/java/dan200/computercraft/client/FrameInfo.java

@@ -7,12 +7,12 @@
 package dan200.computercraft.client;
 
 import dan200.computercraft.ComputerCraft;
+import net.minecraftforge.api.distmarker.Dist;
+import net.minecraftforge.eventbus.api.SubscribeEvent;
 import net.minecraftforge.fml.common.Mod;
-import net.minecraftforge.fml.common.eventhandler.SubscribeEvent;
 import net.minecraftforge.fml.common.gameevent.TickEvent;
-import net.minecraftforge.fml.relauncher.Side;
 
-@Mod.EventBusSubscriber( modid = ComputerCraft.MOD_ID, value = Side.CLIENT )
+@Mod.EventBusSubscriber( modid = ComputerCraft.MOD_ID, value = Dist.CLIENT )
 public final class FrameInfo
 {
     private static int tick;

src/main/java/dan200/computercraft/client/gui/FixedWidthFontRenderer.java

@@ -19,7 +19,7 @@ import org.lwjgl.opengl.GL11;
 
 import java.util.Arrays;
 
-public class FixedWidthFontRenderer
+public final class FixedWidthFontRenderer
 {
     private static final ResourceLocation FONT = new ResourceLocation( "computercraft", "textures/gui/term_font.png" );
     public static final ResourceLocation BACKGROUND = new ResourceLocation( "computercraft", "textures/gui/term_background.png" );
@@ -39,7 +39,7 @@ public class FixedWidthFontRenderer
 
     private FixedWidthFontRenderer()
     {
-        m_textureManager = Minecraft.getMinecraft().getTextureManager();
+        m_textureManager = Minecraft.getInstance().getTextureManager();
     }
 
     private static void greyscaleify( double[] rgb )
@@ -93,7 +93,7 @@ public class FixedWidthFontRenderer
 
     private boolean isGreyScale( int colour )
     {
-        return (colour == 0 || colour == 15 || colour == 7 || colour == 8);
+        return colour == 0 || colour == 15 || colour == 7 || colour == 8;
     }
 
     public void drawStringBackgroundPart( int x, int y, TextBuffer backgroundColour, double leftMarginSize, double rightMarginSize, boolean greyScale, Palette p )
@@ -195,6 +195,6 @@ public class FixedWidthFontRenderer
     public void bindFont()
     {
         m_textureManager.bindTexture( FONT );
-        GlStateManager.glTexParameteri( GL11.GL_TEXTURE_2D, GL11.GL_TEXTURE_WRAP_S, GL11.GL_CLAMP );
+        GlStateManager.texParameteri( GL11.GL_TEXTURE_2D, GL11.GL_TEXTURE_WRAP_S, GL11.GL_CLAMP );
     }
 }

src/main/java/dan200/computercraft/client/gui/GuiComputer.java

@@ -8,23 +8,19 @@ package dan200.computercraft.client.gui;
 
 import dan200.computercraft.ComputerCraft;
 import dan200.computercraft.client.gui.widgets.WidgetTerminal;
+import dan200.computercraft.client.gui.widgets.WidgetWrapper;
 import dan200.computercraft.shared.computer.blocks.TileComputer;
 import dan200.computercraft.shared.computer.core.ClientComputer;
 import dan200.computercraft.shared.computer.core.ComputerFamily;
-import dan200.computercraft.shared.computer.core.IComputer;
 import dan200.computercraft.shared.computer.inventory.ContainerComputer;
 import net.minecraft.client.gui.inventory.GuiContainer;
 import net.minecraft.client.renderer.GlStateManager;
 import net.minecraft.inventory.Container;
 import net.minecraft.util.ResourceLocation;
-import org.lwjgl.input.Keyboard;
-import org.lwjgl.input.Mouse;
-
-import java.io.IOException;
 
 public class GuiComputer extends GuiContainer
 {
-    private static final ResourceLocation BACKGROUND = new ResourceLocation( "computercraft", "textures/gui/corners.png" );
+    private static final ResourceLocation BACKGROUND_NORMAL = new ResourceLocation( "computercraft", "textures/gui/corners_normal.png" );
     private static final ResourceLocation BACKGROUND_ADVANCED = new ResourceLocation( "computercraft", "textures/gui/corners_advanced.png" );
     private static final ResourceLocation BACKGROUND_COMMAND = new ResourceLocation( "computercraft", "textures/gui/corners_command.png" );
 
@@ -32,7 +28,9 @@ public class GuiComputer extends GuiContainer
     private final ClientComputer m_computer;
     private final int m_termWidth;
     private final int m_termHeight;
-    private WidgetTerminal m_terminal;
+
+    private WidgetTerminal terminal;
+    private WidgetWrapper terminalWrapper;
 
     public GuiComputer( Container container, ComputerFamily family, ClientComputer computer, int termWidth, int termHeight )
     {
@@ -41,13 +39,7 @@ public class GuiComputer extends GuiContainer
         m_computer = computer;
         m_termWidth = termWidth;
         m_termHeight = termHeight;
-        m_terminal = null;
+        terminal = null;
-    }
-
-    @Deprecated
-    public GuiComputer( Container container, ComputerFamily family, IComputer computer, int termWidth, int termHeight )
-    {
-        this( container, family, (ClientComputer) computer, termWidth, termHeight );
     }
 
     public GuiComputer( TileComputer computer )
@@ -62,122 +54,67 @@ public class GuiComputer extends GuiContainer
     }
 
     @Override
-    public void initGui()
+    protected void initGui()
     {
-        super.initGui();
+        mc.keyboardListener.enableRepeatEvents( true );
-        Keyboard.enableRepeatEvents( true );
 
-        m_terminal = new WidgetTerminal( 0, 0, m_termWidth, m_termHeight, () -> m_computer, 2, 2, 2, 2 );
+        int termPxWidth = m_termWidth * FixedWidthFontRenderer.FONT_WIDTH;
-        m_terminal.setAllowFocusLoss( false );
+        int termPxHeight = m_termHeight * FixedWidthFontRenderer.FONT_HEIGHT;
-        xSize = m_terminal.getWidth() + 24;
+
-        ySize = m_terminal.getHeight() + 24;
+        xSize = termPxWidth + 4 + 24;
+        ySize = termPxHeight + 4 + 24;
+
+        super.initGui();
+
+        terminal = new WidgetTerminal( mc, () -> m_computer, m_termWidth, m_termHeight, 2, 2, 2, 2 );
+        terminalWrapper = new WidgetWrapper( terminal, 2 + 12 + guiLeft, 2 + 12 + guiTop, termPxWidth, termPxHeight );
+
+        children.add( terminalWrapper );
+        setFocused( terminalWrapper );
     }
 
     @Override
     public void onGuiClosed()
     {
         super.onGuiClosed();
-        Keyboard.enableRepeatEvents( false );
+        children.remove( terminal );
+        terminal = null;
+        mc.keyboardListener.enableRepeatEvents( false );
     }
 
     @Override
-    public boolean doesGuiPauseGame()
+    public void tick()
     {
-        return false;
+        super.tick();
+        terminal.update();
     }
 
     @Override
-    public void updateScreen()
+    public void drawGuiContainerBackgroundLayer( float partialTicks, int mouseX, int mouseY )
-    {
-        super.updateScreen();
-        m_terminal.update();
-    }
-
-    @Override
-    protected void keyTyped( char c, int k ) throws IOException
-    {
-        if( k == 1 )
-        {
-            super.keyTyped( c, k );
-        }
-        else
-        {
-            if( m_terminal.onKeyTyped( c, k ) ) keyHandled = true;
-        }
-    }
-
-    @Override
-    protected void mouseClicked( int x, int y, int button )
-    {
-        int startX = (width - m_terminal.getWidth()) / 2;
-        int startY = (height - m_terminal.getHeight()) / 2;
-        m_terminal.mouseClicked( x - startX, y - startY, button );
-    }
-
-    @Override
-    public void handleMouseInput() throws IOException
-    {
-        super.handleMouseInput();
-
-        int x = Mouse.getEventX() * width / mc.displayWidth;
-        int y = height - Mouse.getEventY() * height / mc.displayHeight - 1;
-        int startX = (width - m_terminal.getWidth()) / 2;
-        int startY = (height - m_terminal.getHeight()) / 2;
-        m_terminal.handleMouseInput( x - startX, y - startY );
-    }
-
-    @Override
-    public void handleKeyboardInput() throws IOException
-    {
-        super.handleKeyboardInput();
-        if( m_terminal.onKeyboardInput() ) keyHandled = true;
-    }
-
-    @Override
-    protected void drawGuiContainerForegroundLayer( int par1, int par2 )
-    {
-    }
-
-    @Override
-    protected void drawGuiContainerBackgroundLayer( float var1, int var2, int var3 )
-    {
-    }
-
-    @Override
-    public void drawScreen( int mouseX, int mouseY, float f )
     {
         // Work out where to draw
-        int startX = (width - m_terminal.getWidth()) / 2;
+        int startX = terminalWrapper.getX() - 2;
-        int startY = (height - m_terminal.getHeight()) / 2;
+        int startY = terminalWrapper.getY() - 2;
-        int endX = startX + m_terminal.getWidth();
+        int endX = startX + terminalWrapper.getWidth() + 4;
-        int endY = startY + m_terminal.getHeight();
+        int endY = startY + terminalWrapper.getHeight() + 4;
-
-        // Draw background
-        drawDefaultBackground();
 
         // Draw terminal
-        m_terminal.draw( this.mc, startX, startY, mouseX, mouseY );
+        terminal.draw( terminalWrapper.getX(), terminalWrapper.getY() );
 
         // Draw a border around the terminal
-        GlStateManager.color( 1.0f, 1.0f, 1.0f, 1.0f );
+        GlStateManager.color4f( 1.0f, 1.0f, 1.0f, 1.0f );
         switch( m_family )
         {
             case Normal:
             default:
-            {
+                mc.getTextureManager().bindTexture( BACKGROUND_NORMAL );
-                this.mc.getTextureManager().bindTexture( BACKGROUND );
                 break;
-            }
             case Advanced:
-            {
+                mc.getTextureManager().bindTexture( BACKGROUND_ADVANCED );
-                this.mc.getTextureManager().bindTexture( BACKGROUND_ADVANCED );
                 break;
-            }
             case Command:
-            {
+                mc.getTextureManager().bindTexture( BACKGROUND_COMMAND );
-                this.mc.getTextureManager().bindTexture( BACKGROUND_COMMAND );
                 break;
-            }
         }
 
         drawTexturedModalRect( startX - 12, startY - 12, 12, 28, 12, 12 );
@@ -191,4 +128,26 @@ public class GuiComputer extends GuiContainer
         drawTexturedModalRect( startX - 12, startY, 0, 28, 12, endY - startY );
         drawTexturedModalRect( endX, startY, 36, 28, 12, endY - startY );
     }
+
+    @Override
+    public void render( int mouseX, int mouseY, float partialTicks )
+    {
+        drawDefaultBackground();
+        super.render( mouseX, mouseY, partialTicks );
+        renderHoveredToolTip( mouseX, mouseY );
+    }
+
+    @Override
+    public boolean mouseDragged( double x, double y, int button, double deltaX, double deltaY )
+    {
+        return (getFocused() != null && getFocused().mouseDragged( x, y, button, deltaX, deltaY ))
+            || super.mouseDragged( x, y, button, deltaX, deltaY );
+    }
+
+    @Override
+    public boolean mouseReleased( double x, double y, int button )
+    {
+        return (getFocused() != null && getFocused().mouseReleased( x, y, button ))
+            || super.mouseReleased( x, y, button );
+    }
 }

src/main/java/dan200/computercraft/client/gui/GuiConfigCC.java

@@ -1,52 +0,0 @@
-/*
- * This file is part of ComputerCraft - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
- * Send enquiries to dratcliffe@gmail.com
- */
-
-package dan200.computercraft.client.gui;
-
-import dan200.computercraft.ComputerCraft;
-import dan200.computercraft.shared.Config;
-import net.minecraft.client.Minecraft;
-import net.minecraft.client.gui.GuiScreen;
-import net.minecraftforge.fml.client.IModGuiFactory;
-import net.minecraftforge.fml.client.config.GuiConfig;
-
-import java.util.Set;
-
-public class GuiConfigCC extends GuiConfig
-{
-    public GuiConfigCC( GuiScreen parentScreen )
-    {
-        super( parentScreen, Config.getConfigElements(), ComputerCraft.MOD_ID, false, false, "CC: Tweaked" );
-    }
-
-    public static class Factory
-        implements IModGuiFactory
-    {
-
-        @Override
-        public void initialize( Minecraft minecraft )
-        {
-        }
-
-        @Override
-        public boolean hasConfigGui()
-        {
-            return true;
-        }
-
-        @Override
-        public GuiScreen createConfigGui( GuiScreen parentScreen )
-        {
-            return new GuiConfigCC( parentScreen );
-        }
-
-        @Override
-        public Set<RuntimeOptionCategoryElement> runtimeGuiCategories()
-        {
-            return null;
-        }
-    }
-}

src/main/java/dan200/computercraft/client/gui/GuiDiskDrive.java

@@ -14,7 +14,7 @@ import net.minecraft.util.ResourceLocation;
 
 public class GuiDiskDrive extends GuiContainer
 {
-    private static final ResourceLocation BACKGROUND = new ResourceLocation( "computercraft", "textures/gui/diskdrive.png" );
+    private static final ResourceLocation BACKGROUND = new ResourceLocation( "computercraft", "textures/gui/disk_drive.png" );
 
     private final ContainerDiskDrive m_container;
 
@@ -25,28 +25,26 @@ public class GuiDiskDrive extends GuiContainer
     }
 
     @Override
-    protected void drawGuiContainerForegroundLayer( int par1, int par2 )
+    protected void drawGuiContainerForegroundLayer( int mouseX, int mouseY )
     {
-        String title = m_container.getDiskDrive().getDisplayName().getUnformattedText();
+        String title = m_container.getDiskDrive().getDisplayName().getString();
-        fontRenderer.drawString( title, (xSize - fontRenderer.getStringWidth( title )) / 2, 6, 0x404040 );
+        fontRenderer.drawString( title, (xSize - fontRenderer.getStringWidth( title )) / 2.0f, 6, 0x404040 );
-        fontRenderer.drawString( I18n.format( "container.inventory" ), 8, (ySize - 96) + 2, 0x404040 );
+        fontRenderer.drawString( I18n.format( "container.inventory" ), 8, ySize - 96 + 2, 0x404040 );
     }
 
     @Override
-    protected void drawGuiContainerBackgroundLayer( float f, int i, int j )
+    protected void drawGuiContainerBackgroundLayer( float partialTicks, int mouseX, int mouseY )
     {
-        GlStateManager.color( 1.0F, 1.0F, 1.0F, 1.0F );
+        GlStateManager.color4f( 1.0F, 1.0F, 1.0F, 1.0F );
-        this.mc.getTextureManager().bindTexture( BACKGROUND );
+        mc.getTextureManager().bindTexture( BACKGROUND );
-        int l = (width - xSize) / 2;
+        drawTexturedModalRect( guiLeft, guiTop, 0, 0, xSize, ySize );
-        int i1 = (height - ySize) / 2;
-        drawTexturedModalRect( l, i1, 0, 0, xSize, ySize );
     }
 
     @Override
-    public void drawScreen( int mouseX, int mouseY, float partialTicks )
+    public void render( int mouseX, int mouseY, float partialTicks )
     {
         drawDefaultBackground();
-        super.drawScreen( mouseX, mouseY, partialTicks );
+        super.render( mouseX, mouseY, partialTicks );
         renderHoveredToolTip( mouseX, mouseY );
     }
 }

src/main/java/dan200/computercraft/client/gui/GuiPocketComputer.java

@@ -7,18 +7,28 @@
 package dan200.computercraft.client.gui;
 
 import dan200.computercraft.ComputerCraft;
-import dan200.computercraft.shared.media.inventory.ContainerHeldItem;
+import dan200.computercraft.shared.computer.core.ComputerFamily;
+import dan200.computercraft.shared.pocket.inventory.ContainerPocketComputer;
+import dan200.computercraft.shared.pocket.items.ItemPocketComputer;
+import net.minecraft.item.Item;
+import net.minecraft.item.ItemStack;
 
 public class GuiPocketComputer extends GuiComputer
 {
-    public GuiPocketComputer( ContainerHeldItem container )
+    public GuiPocketComputer( ContainerPocketComputer container )
     {
         super(
             container,
-            ComputerCraft.Items.pocketComputer.getFamily( container.getStack() ),
+            getFamily( container.getStack() ),
-            ComputerCraft.Items.pocketComputer.createClientComputer( container.getStack() ),
+            ItemPocketComputer.createClientComputer( container.getStack() ),
             ComputerCraft.terminalWidth_pocketComputer,
             ComputerCraft.terminalHeight_pocketComputer
         );
     }
+
+    private static ComputerFamily getFamily( ItemStack stack )
+    {
+        Item item = stack.getItem();
+        return item instanceof ItemPocketComputer ? ((ItemPocketComputer) item).getFamily() : ComputerFamily.Normal;
+    }
 }

src/main/java/dan200/computercraft/client/gui/GuiPrinter.java

@@ -16,43 +16,37 @@ public class GuiPrinter extends GuiContainer
 {
     private static final ResourceLocation BACKGROUND = new ResourceLocation( "computercraft", "textures/gui/printer.png" );
 
-    private final ContainerPrinter m_container;
+    private final ContainerPrinter container;
 
     public GuiPrinter( ContainerPrinter container )
     {
         super( container );
-        m_container = container;
+        this.container = container;
     }
 
     @Override
-    protected void drawGuiContainerForegroundLayer( int par1, int par2 )
+    protected void drawGuiContainerForegroundLayer( int mouseX, int mouseY )
     {
-        String title = m_container.getPrinter().getDisplayName().getUnformattedText();
+        String title = container.getPrinter().getDisplayName().getString();
-        fontRenderer.drawString( title, (xSize - fontRenderer.getStringWidth( title )) / 2, 6, 0x404040 );
+        fontRenderer.drawString( title, (xSize - fontRenderer.getStringWidth( title )) / 2.0f, 6, 0x404040 );
-        fontRenderer.drawString( I18n.format( "container.inventory" ), 8, (ySize - 96) + 2, 0x404040 );
+        fontRenderer.drawString( I18n.format( "container.inventory" ), 8, ySize - 96 + 2, 0x404040 );
     }
 
     @Override
-    protected void drawGuiContainerBackgroundLayer( float f, int i, int j )
+    protected void drawGuiContainerBackgroundLayer( float partialTicks, int mouseX, int mouseY )
     {
-        GlStateManager.color( 1.0F, 1.0F, 1.0F, 1.0F );
+        GlStateManager.color4f( 1.0F, 1.0F, 1.0F, 1.0F );
-        this.mc.getTextureManager().bindTexture( BACKGROUND );
+        mc.getTextureManager().bindTexture( BACKGROUND );
-        int startX = (width - xSize) / 2;
+        drawTexturedModalRect( guiLeft, guiTop, 0, 0, xSize, ySize );
-        int startY = (height - ySize) / 2;
-        drawTexturedModalRect( startX, startY, 0, 0, xSize, ySize );
 
-        boolean printing = m_container.isPrinting();
+        if( container.isPrinting() ) drawTexturedModalRect( guiLeft + 34, guiTop + 21, 176, 0, 25, 45 );
-        if( printing )
-        {
-            drawTexturedModalRect( startX + 34, startY + 21, 176, 0, 25, 45 );
-        }
     }
 
     @Override
-    public void drawScreen( int mouseX, int mouseY, float partialTicks )
+    public void render( int mouseX, int mouseY, float partialTicks )
     {
         drawDefaultBackground();
-        super.drawScreen( mouseX, mouseY, partialTicks );
+        super.render( mouseX, mouseY, partialTicks );
         renderHoveredToolTip( mouseX, mouseY );
     }
 }

src/main/java/dan200/computercraft/client/gui/GuiPrintout.java

@@ -7,13 +7,11 @@
 package dan200.computercraft.client.gui;
 
 import dan200.computercraft.core.terminal.TextBuffer;
-import dan200.computercraft.shared.media.inventory.ContainerHeldItem;
+import dan200.computercraft.shared.common.ContainerHeldItem;
 import dan200.computercraft.shared.media.items.ItemPrintout;
 import net.minecraft.client.gui.inventory.GuiContainer;
 import net.minecraft.client.renderer.GlStateManager;
-import org.lwjgl.input.Mouse;
+import org.lwjgl.glfw.GLFW;
-
-import java.io.IOException;
 
 import static dan200.computercraft.client.render.PrintoutRenderer.*;
 
@@ -29,6 +27,8 @@ public class GuiPrintout extends GuiContainer
     {
         super( container );
 
+        ySize = Y_SIZE;
+
         String[] text = ItemPrintout.getText( container.getStack() );
         m_text = new TextBuffer[text.length];
         for( int i = 0; i < m_text.length; i++ ) m_text[i] = new TextBuffer( text[i] );
@@ -39,75 +39,70 @@ public class GuiPrintout extends GuiContainer
 
         m_page = 0;
         m_pages = Math.max( m_text.length / ItemPrintout.LINES_PER_PAGE, 1 );
-        m_book = ItemPrintout.getType( container.getStack() ) == ItemPrintout.Type.Book;
+        m_book = ((ItemPrintout) container.getStack().getItem()).getType() == ItemPrintout.Type.BOOK;
     }
 
     @Override
-    public boolean doesGuiPauseGame()
+    public boolean keyPressed( int key, int scancode, int modifiers )
     {
+        if( super.keyPressed( key, scancode, modifiers ) ) return true;
+
+        if( key == GLFW.GLFW_KEY_RIGHT )
+        {
+            if( m_page < m_pages - 1 ) m_page++;
+            return true;
+        }
+
+        if( key == GLFW.GLFW_KEY_LEFT )
+        {
+            if( m_page > 0 ) m_page--;
+            return true;
+        }
+
         return false;
     }
 
     @Override
-    protected void keyTyped( char c, int k ) throws IOException
+    public boolean mouseScrolled( double delta )
     {
-        super.keyTyped( c, k );
+        if( super.mouseScrolled( delta ) ) return true;
-
+        if( delta < 0 )
-        if( k == 205 )
         {
-            // Right
+            // Scroll up goes to the next page
             if( m_page < m_pages - 1 ) m_page++;
+            return true;
         }
-        else if( k == 203 )
+
+        if( delta > 0 )
         {
-            // Left
+            // Scroll down goes to the previous page
             if( m_page > 0 ) m_page--;
+            return true;
         }
+
+        return false;
     }
 
     @Override
-    public void handleMouseInput() throws IOException
+    public void drawGuiContainerBackgroundLayer( float partialTicks, int mouseX, int mouseY )
     {
-        super.handleMouseInput();
-
-        int mouseWheelChange = Mouse.getEventDWheel();
-        if( mouseWheelChange < 0 )
-        {
-            // Up
-            if( m_page < m_pages - 1 ) m_page++;
-        }
-        else if( mouseWheelChange > 0 )
-        {
-            // Down
-            if( m_page > 0 ) m_page--;
-        }
-    }
-
-    @Override
-    protected void drawGuiContainerForegroundLayer( int par1, int par2 )
-    {
-    }
-
-    @Override
-    protected void drawGuiContainerBackgroundLayer( float var1, int var2, int var3 )
-    {
-    }
-
-    @Override
-    public void drawScreen( int mouseX, int mouseY, float f )
-    {
-        // Draw background
-        zLevel = zLevel - 1;
-        drawDefaultBackground();
-        zLevel = zLevel + 1;
-
         // Draw the printout
-        GlStateManager.color( 1.0f, 1.0f, 1.0f, 1.0f );
+        GlStateManager.color4f( 1.0f, 1.0f, 1.0f, 1.0f );
+        GlStateManager.enableDepthTest();
 
-        int startY = (height - Y_SIZE) / 2;
+        drawBorder( guiLeft, guiTop, zLevel, m_page, m_pages, m_book );
-        int startX = (width - X_SIZE) / 2;
+        drawText( guiLeft + X_TEXT_MARGIN, guiTop + Y_TEXT_MARGIN, ItemPrintout.LINES_PER_PAGE * m_page, m_text, m_colours );
+    }
 
-        drawBorder( startX, startY, zLevel, m_page, m_pages, m_book );
+    @Override
-        drawText( startX + X_TEXT_MARGIN, startY + Y_TEXT_MARGIN, ItemPrintout.LINES_PER_PAGE * m_page, m_text, m_colours );
+    public void render( int mouseX, int mouseY, float partialTicks )
+    {
+        // We must take the background further back in order to not overlap with our printed pages.
+        zLevel--;
+        drawDefaultBackground();
+        zLevel++;
+
+        super.render( mouseX, mouseY, partialTicks );
+        renderHoveredToolTip( mouseX, mouseY );
     }
 }

src/main/java/dan200/computercraft/client/gui/GuiTurtle.java

@@ -8,29 +8,27 @@ package dan200.computercraft.client.gui;
 
 import dan200.computercraft.ComputerCraft;
 import dan200.computercraft.client.gui.widgets.WidgetTerminal;
+import dan200.computercraft.client.gui.widgets.WidgetWrapper;
 import dan200.computercraft.shared.computer.core.ClientComputer;
 import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.turtle.blocks.TileTurtle;
 import dan200.computercraft.shared.turtle.inventory.ContainerTurtle;
-import net.minecraft.client.Minecraft;
 import net.minecraft.client.gui.inventory.GuiContainer;
 import net.minecraft.client.renderer.GlStateManager;
 import net.minecraft.util.ResourceLocation;
-import org.lwjgl.input.Keyboard;
-import org.lwjgl.input.Mouse;
-
-import java.io.IOException;
 
 public class GuiTurtle extends GuiContainer
 {
-    private static final ResourceLocation BACKGROUND = new ResourceLocation( "computercraft", "textures/gui/turtle.png" );
+    private static final ResourceLocation BACKGROUND_NORMAL = new ResourceLocation( "computercraft", "textures/gui/turtle_normal.png" );
     private static final ResourceLocation BACKGROUND_ADVANCED = new ResourceLocation( "computercraft", "textures/gui/turtle_advanced.png" );
 
     private ContainerTurtle m_container;
 
     private final ComputerFamily m_family;
     private final ClientComputer m_computer;
-    private WidgetTerminal m_terminalGui;
+
+    private WidgetTerminal terminal;
+    private WidgetWrapper terminalWrapper;
 
     public GuiTurtle( TileTurtle turtle, ContainerTurtle container )
     {
@@ -45,110 +43,75 @@ public class GuiTurtle extends GuiContainer
     }
 
     @Override
-    public void initGui()
+    protected void initGui()
     {
         super.initGui();
-        Keyboard.enableRepeatEvents( true );
+        mc.keyboardListener.enableRepeatEvents( true );
-        m_terminalGui = new WidgetTerminal(
+
-            (width - xSize) / 2 + 8,
+        int termPxWidth = ComputerCraft.terminalWidth_turtle * FixedWidthFontRenderer.FONT_WIDTH;
-            (height - ySize) / 2 + 8,
+        int termPxHeight = ComputerCraft.terminalHeight_turtle * FixedWidthFontRenderer.FONT_HEIGHT;
+
+        terminal = new WidgetTerminal(
+            mc, () -> m_computer,
             ComputerCraft.terminalWidth_turtle,
             ComputerCraft.terminalHeight_turtle,
-            () -> m_computer,
             2, 2, 2, 2
         );
-        m_terminalGui.setAllowFocusLoss( false );
+        terminalWrapper = new WidgetWrapper( terminal, 2 + 8 + guiLeft, 2 + 8 + guiTop, termPxWidth, termPxHeight );
+
+        children.add( terminalWrapper );
+        setFocused( terminalWrapper );
     }
 
     @Override
     public void onGuiClosed()
     {
-        super.onGuiClosed();
+        children.remove( terminal );
-        Keyboard.enableRepeatEvents( false );
+        terminal = null;
+        mc.keyboardListener.enableRepeatEvents( false );
     }
 
     @Override
-    public void updateScreen()
+    public void tick()
     {
-        super.updateScreen();
+        super.tick();
-        m_terminalGui.update();
+        terminal.update();
     }
 
-    @Override
+    private void drawSelectionSlot( boolean advanced )
-    protected void keyTyped( char c, int k ) throws IOException
     {
-        if( k == 1 )
-        {
-            super.keyTyped( c, k );
-        }
-        else
-        {
-            if( m_terminalGui.onKeyTyped( c, k ) ) keyHandled = true;
-        }
-    }
-
-    @Override
-    protected void mouseClicked( int x, int y, int button ) throws IOException
-    {
-        super.mouseClicked( x, y, button );
-        m_terminalGui.mouseClicked( x, y, button );
-    }
-
-    @Override
-    public void handleMouseInput() throws IOException
-    {
-        super.handleMouseInput();
-        int x = Mouse.getEventX() * this.width / mc.displayWidth;
-        int y = this.height - Mouse.getEventY() * this.height / mc.displayHeight - 1;
-        m_terminalGui.handleMouseInput( x, y );
-    }
-
-    @Override
-    public void handleKeyboardInput() throws IOException
-    {
-        super.handleKeyboardInput();
-        if( m_terminalGui.onKeyboardInput() ) keyHandled = true;
-    }
-
-    protected void drawSelectionSlot( boolean advanced )
-    {
-        int x = (width - xSize) / 2;
-        int y = (height - ySize) / 2;
-
         // Draw selection slot
         int slot = m_container.getSelectedSlot();
         if( slot >= 0 )
         {
-            GlStateManager.color( 1.0F, 1.0F, 1.0F, 1.0F );
+            GlStateManager.color4f( 1.0F, 1.0F, 1.0F, 1.0F );
-            int slotX = (slot % 4);
+            int slotX = slot % 4;
-            int slotY = (slot / 4);
+            int slotY = slot / 4;
-            this.mc.getTextureManager().bindTexture( advanced ? BACKGROUND_ADVANCED : BACKGROUND );
+            mc.getTextureManager().bindTexture( advanced ? BACKGROUND_ADVANCED : BACKGROUND_NORMAL );
-            drawTexturedModalRect( x + m_container.m_turtleInvStartX - 2 + slotX * 18, y + m_container.m_playerInvStartY - 2 + slotY * 18, 0, 217, 24, 24 );
+            drawTexturedModalRect( guiLeft + m_container.m_turtleInvStartX - 2 + slotX * 18, guiTop + m_container.m_playerInvStartY - 2 + slotY * 18, 0, 217, 24, 24 );
         }
     }
 
     @Override
-    protected void drawGuiContainerBackgroundLayer( float f, int mouseX, int mouseY )
+    protected void drawGuiContainerBackgroundLayer( float partialTicks, int mouseX, int mouseY )
     {
         // Draw term
-        boolean advanced = (m_family == ComputerFamily.Advanced);
+        boolean advanced = m_family == ComputerFamily.Advanced;
-        m_terminalGui.draw( Minecraft.getMinecraft(), 0, 0, mouseX, mouseY );
+        terminal.draw( terminalWrapper.getX(), terminalWrapper.getY() );
 
         // Draw border/inventory
-        GlStateManager.color( 1.0F, 1.0F, 1.0F, 1.0F );
+        GlStateManager.color4f( 1.0F, 1.0F, 1.0F, 1.0F );
-        this.mc.getTextureManager().bindTexture( advanced ? BACKGROUND_ADVANCED : BACKGROUND );
+        mc.getTextureManager().bindTexture( advanced ? BACKGROUND_ADVANCED : BACKGROUND_NORMAL );
-        int x = (width - xSize) / 2;
+        drawTexturedModalRect( guiLeft, guiTop, 0, 0, xSize, ySize );
-        int y = (height - ySize) / 2;
-        drawTexturedModalRect( x, y, 0, 0, xSize, ySize );
 
         drawSelectionSlot( advanced );
     }
 
     @Override
-    public void drawScreen( int mouseX, int mouseY, float partialTicks )
+    public void render( int mouseX, int mouseY, float partialTicks )
     {
         drawDefaultBackground();
-        super.drawScreen( mouseX, mouseY, partialTicks );
+        super.render( mouseX, mouseY, partialTicks );
         renderHoveredToolTip( mouseX, mouseY );
     }
 }

src/main/java/dan200/computercraft/client/gui/widgets/Widget.java

@@ -1,84 +0,0 @@
-/*
- * This file is part of ComputerCraft - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
- * Send enquiries to dratcliffe@gmail.com
- */
-
-package dan200.computercraft.client.gui.widgets;
-
-import net.minecraft.client.Minecraft;
-import net.minecraft.client.gui.Gui;
-
-public abstract class Widget extends Gui
-{
-    private int m_xPosition;
-    private int m_yPosition;
-    private int m_width;
-    private int m_height;
-
-    protected Widget( int x, int y, int width, int height )
-    {
-        m_xPosition = x;
-        m_yPosition = y;
-        m_width = width;
-        m_height = height;
-    }
-
-    public int getXPosition()
-    {
-        return m_xPosition;
-    }
-
-    public int getYPosition()
-    {
-        return m_yPosition;
-    }
-
-    public int getWidth()
-    {
-        return m_width;
-    }
-
-    public int getHeight()
-    {
-        return m_height;
-    }
-
-    public void update()
-    {
-    }
-
-    public void draw( Minecraft mc, int xOrigin, int yOrigin, int mouseX, int mouseY )
-    {
-    }
-
-    public void handleMouseInput( int mouseX, int mouseY )
-    {
-    }
-
-    public boolean onKeyboardInput()
-    {
-        return false;
-    }
-
-    @Deprecated
-    public void handleKeyboardInput()
-    {
-        onKeyboardInput();
-    }
-
-    public void mouseClicked( int mouseX, int mouseY, int mouseButton )
-    {
-    }
-
-    public boolean onKeyTyped( char c, int k )
-    {
-        return false;
-    }
-
-    @Deprecated
-    public void keyTyped( char c, int k )
-    {
-        onKeyTyped( c, k );
-    }
-}

src/main/java/dan200/computercraft/client/gui/widgets/WidgetTerminal.java

@@ -10,411 +10,349 @@ import dan200.computercraft.client.FrameInfo;
 import dan200.computercraft.client.gui.FixedWidthFontRenderer;
 import dan200.computercraft.core.terminal.Terminal;
 import dan200.computercraft.core.terminal.TextBuffer;
+import dan200.computercraft.shared.computer.core.ClientComputer;
 import dan200.computercraft.shared.computer.core.IComputer;
-import dan200.computercraft.shared.computer.core.IComputerContainer;
 import dan200.computercraft.shared.util.Colour;
 import dan200.computercraft.shared.util.Palette;
 import net.minecraft.client.Minecraft;
-import net.minecraft.client.gui.GuiScreen;
+import net.minecraft.client.gui.IGuiEventListener;
+import net.minecraft.client.renderer.BufferBuilder;
 import net.minecraft.client.renderer.GlStateManager;
-import net.minecraft.util.ChatAllowedCharacters;
+import net.minecraft.client.renderer.Tessellator;
-import org.lwjgl.input.Keyboard;
+import net.minecraft.client.renderer.vertex.DefaultVertexFormats;
-import org.lwjgl.input.Mouse;
+import net.minecraft.util.SharedConstants;
+import org.lwjgl.glfw.GLFW;
+import org.lwjgl.opengl.GL11;
 
-import java.util.ArrayList;
+import java.util.BitSet;
+import java.util.function.Supplier;
 
 import static dan200.computercraft.client.gui.FixedWidthFontRenderer.BACKGROUND;
 
-public class WidgetTerminal extends Widget
+public class WidgetTerminal implements IGuiEventListener
 {
     private static final float TERMINATE_TIME = 0.5f;
 
-    private final IComputerContainer m_computer;
+    private final Minecraft client;
 
-    private float m_terminateTimer;
+    private final Supplier<ClientComputer> computer;
-    private float m_rebootTimer;
+    private final int termWidth;
-    private float m_shutdownTimer;
+    private final int termHeight;
 
-    private int m_lastClickButton;
+    private float terminateTimer = -1;
-    private int m_lastClickX;
+    private float rebootTimer = -1;
-    private int m_lastClickY;
+    private float shutdownTimer = -1;
 
-    private boolean m_focus;
+    private int lastMouseButton = -1;
-    private boolean m_allowFocusLoss;
+    private int lastMouseX = -1;
+    private int lastMouseY = -1;
 
-    private int m_leftMargin;
+    private final int leftMargin;
-    private int m_rightMargin;
+    private final int rightMargin;
-    private int m_topMargin;
+    private final int topMargin;
-    private int m_bottomMargin;
+    private final int bottomMargin;
 
-    private ArrayList<Integer> m_keysDown;
+    private final BitSet keysDown = new BitSet( 256 );
 
-    public WidgetTerminal( int x, int y, int termWidth, int termHeight, IComputerContainer computer, int leftMargin, int rightMargin, int topMargin, int bottomMargin )
+    public WidgetTerminal( Minecraft client, Supplier<ClientComputer> computer, int termWidth, int termHeight, int leftMargin, int rightMargin, int topMargin, int bottomMargin )
     {
-        super(
+        this.client = client;
-            x, y,
+        this.computer = computer;
-            leftMargin + rightMargin + termWidth * FixedWidthFontRenderer.FONT_WIDTH,
+        this.termWidth = termWidth;
-            topMargin + bottomMargin + termHeight * FixedWidthFontRenderer.FONT_HEIGHT
+        this.termHeight = termHeight;
-        );
+        this.leftMargin = leftMargin;
-
+        this.rightMargin = rightMargin;
-        m_computer = computer;
+        this.topMargin = topMargin;
-        m_terminateTimer = 0.0f;
+        this.bottomMargin = bottomMargin;
-        m_rebootTimer = 0.0f;
-        m_shutdownTimer = 0.0f;
-
-        m_lastClickButton = -1;
-        m_lastClickX = -1;
-        m_lastClickY = -1;
-
-        m_focus = false;
-        m_allowFocusLoss = true;
-
-        m_leftMargin = leftMargin;
-        m_rightMargin = rightMargin;
-        m_topMargin = topMargin;
-        m_bottomMargin = bottomMargin;
-
-        m_keysDown = new ArrayList<>();
-    }
-
-    public void setAllowFocusLoss( boolean allowFocusLoss )
-    {
-        m_allowFocusLoss = allowFocusLoss;
-        m_focus = m_focus || !allowFocusLoss;
     }
 
     @Override
-    public boolean onKeyTyped( char ch, int key )
+    public boolean charTyped( char ch, int modifiers )
     {
-        if( m_focus )
+        if( ch >= 32 && ch <= 126 || ch >= 160 && ch <= 255 ) // printable chars in byte range
         {
-            // Ctrl+V for paste
+            // Queue the "char" event
-            if( ch == 22 )
+            queueEvent( "char", Character.toString( ch ) );
+        }
+
+        return true;
+    }
+
+    @Override
+    public boolean keyPressed( int key, int scancode, int modifiers )
+    {
+        if( key == GLFW.GLFW_KEY_ESCAPE ) return false;
+        if( (modifiers & GLFW.GLFW_MOD_CONTROL) != 0 )
+        {
+            switch( key )
             {
-                String clipboard = GuiScreen.getClipboardString();
+                case GLFW.GLFW_KEY_T:
-                if( clipboard != null )
+                    if( terminateTimer < 0 ) terminateTimer = 0;
-                {
+                    return true;
-                    // Clip to the first occurance of \r or \n
+                case GLFW.GLFW_KEY_S:
-                    int newLineIndex1 = clipboard.indexOf( "\r" );
+                    if( shutdownTimer < 0 ) shutdownTimer = 0;
-                    int newLineIndex2 = clipboard.indexOf( "\n" );
+                    return true;
-                    if( newLineIndex1 >= 0 && newLineIndex2 >= 0 )
+                case GLFW.GLFW_KEY_R:
-                    {
+                    if( rebootTimer < 0 ) rebootTimer = 0;
-                        clipboard = clipboard.substring( 0, Math.min( newLineIndex1, newLineIndex2 ) );
+                    return true;
-                    }
-                    else if( newLineIndex1 >= 0 )
-                    {
-                        clipboard = clipboard.substring( 0, newLineIndex1 );
-                    }
-                    else if( newLineIndex2 >= 0 )
-                    {
-                        clipboard = clipboard.substring( 0, newLineIndex2 );
-                    }
 
-                    // Filter the string
+                case GLFW.GLFW_KEY_V:
-                    clipboard = ChatAllowedCharacters.filterAllowedCharacters( clipboard );
+                    // Ctrl+V for paste
-
+                    String clipboard = client.keyboardListener.getClipboardString();
-                    if( !clipboard.isEmpty() )
+                    if( clipboard != null )
                     {
-                        // Clip to 512 characters
+                        // Clip to the first occurrence of \r or \n
-                        if( clipboard.length() > 512 )
+                        int newLineIndex1 = clipboard.indexOf( "\r" );
+                        int newLineIndex2 = clipboard.indexOf( "\n" );
+                        if( newLineIndex1 >= 0 && newLineIndex2 >= 0 )
                         {
-                            clipboard = clipboard.substring( 0, 512 );
+                            clipboard = clipboard.substring( 0, Math.min( newLineIndex1, newLineIndex2 ) );
+                        }
+                        else if( newLineIndex1 >= 0 )
+                        {
+                            clipboard = clipboard.substring( 0, newLineIndex1 );
+                        }
+                        else if( newLineIndex2 >= 0 )
+                        {
+                            clipboard = clipboard.substring( 0, newLineIndex2 );
                         }
 
-                        // Queue the "paste" event
+                        // Filter the string
-                        queueEvent( "paste", new Object[] {
+                        clipboard = SharedConstants.filterAllowedCharacters( clipboard );
-                            clipboard
+                        if( !clipboard.isEmpty() )
-                        } );
+                        {
-                    }
+                            // Clip to 512 characters and queue the event
-                }
+                            if( clipboard.length() > 512 ) clipboard = clipboard.substring( 0, 512 );
-                return true;
+                            queueEvent( "paste", clipboard );
-            }
+                        }
 
-            // Regular keys normally
+                        return true;
-            if( m_terminateTimer <= 0.0f && m_rebootTimer <= 0.0f && m_shutdownTimer <= 0.0f )
+                    }
+            }
+        }
+
+        if( key >= 0 && terminateTimer < 0 && rebootTimer < 0 && shutdownTimer < 0 )
+        {
+            // Queue the "key" event and add to the down set
+            boolean repeat = keysDown.get( key );
+            keysDown.set( key );
+            IComputer computer = this.computer.get();
+            if( computer != null ) computer.keyDown( key, repeat );
+        }
+
+        return true;
+    }
+
+    @Override
+    public boolean keyReleased( int key, int scancode, int modifiers )
+    {
+        // Queue the "key_up" event and remove from the down set
+        if( key >= 0 && keysDown.get( key ) )
+        {
+            keysDown.set( key, false );
+            IComputer computer = this.computer.get();
+            if( computer != null ) computer.keyUp( key );
+        }
+
+        switch( key )
+        {
+            case GLFW.GLFW_KEY_T:
+                terminateTimer = -1;
+                break;
+            case GLFW.GLFW_KEY_R:
+                rebootTimer = -1;
+                break;
+            case GLFW.GLFW_KEY_S:
+                shutdownTimer = -1;
+                break;
+            case GLFW.GLFW_KEY_LEFT_CONTROL:
+            case GLFW.GLFW_KEY_RIGHT_CONTROL:
+                terminateTimer = rebootTimer = shutdownTimer = -1;
+                break;
+        }
+
+        return true;
+    }
+
+    @Override
+    public boolean mouseClicked( double mouseX, double mouseY, int button )
+    {
+        ClientComputer computer = this.computer.get();
+        if( computer == null || !computer.isColour() || button < 0 || button > 2 ) return false;
+
+        Terminal term = computer.getTerminal();
+        if( term != null )
+        {
+            int charX = (int) (mouseX / FixedWidthFontRenderer.FONT_WIDTH);
+            int charY = (int) (mouseY / FixedWidthFontRenderer.FONT_HEIGHT);
+            charX = Math.min( Math.max( charX, 0 ), term.getWidth() - 1 );
+            charY = Math.min( Math.max( charY, 0 ), term.getHeight() - 1 );
+
+            computer.mouseClick( button + 1, charX + 1, charY + 1 );
+
+            lastMouseButton = button;
+            lastMouseX = charX;
+            lastMouseY = charY;
+        }
+
+        return true;
+    }
+
+    @Override
+    public boolean mouseReleased( double mouseX, double mouseY, int button )
+    {
+        ClientComputer computer = this.computer.get();
+        if( computer == null || !computer.isColour() || button < 0 || button > 2 ) return false;
+
+        Terminal term = computer.getTerminal();
+        if( term != null )
+        {
+            int charX = (int) (mouseX / FixedWidthFontRenderer.FONT_WIDTH);
+            int charY = (int) (mouseY / FixedWidthFontRenderer.FONT_HEIGHT);
+            charX = Math.min( Math.max( charX, 0 ), term.getWidth() - 1 );
+            charY = Math.min( Math.max( charY, 0 ), term.getHeight() - 1 );
+
+            if( lastMouseButton == button )
             {
-                boolean repeat = Keyboard.isRepeatEvent();
+                computer.mouseUp( lastMouseButton + 1, charX + 1, charY + 1 );
-                boolean handled = false;
+                lastMouseButton = -1;
-                if( key > 0 )
-                {
-                    if( !repeat )
-                    {
-                        m_keysDown.add( key );
-                    }
-
-                    // Queue the "key" event
-                    queueEvent( "key", new Object[] {
-                        key, repeat
-                    } );
-                    handled = true;
-                }
-
-                if( (ch >= 32 && ch <= 126) || (ch >= 160 && ch <= 255) ) // printable chars in byte range
-                {
-                    // Queue the "char" event
-                    queueEvent( "char", new Object[] {
-                        Character.toString( ch )
-                    } );
-                    handled = true;
-                }
-
-                return handled;
             }
+
+            lastMouseX = charX;
+            lastMouseY = charY;
         }
 
         return false;
     }
 
     @Override
-    public void mouseClicked( int mouseX, int mouseY, int button )
+    public boolean mouseDragged( double mouseX, double mouseY, int button, double v2, double v3 )
     {
-        if( mouseX >= getXPosition() && mouseX < getXPosition() + getWidth() &&
+        ClientComputer computer = this.computer.get();
-            mouseY >= getYPosition() && mouseY < getYPosition() + getHeight() )
+        if( computer == null || !computer.isColour() || button < 0 || button > 2 ) return false;
+
+        Terminal term = computer.getTerminal();
+        if( term != null )
         {
-            if( !m_focus && button == 0 )
+            int charX = (int) (mouseX / FixedWidthFontRenderer.FONT_WIDTH);
-            {
+            int charY = (int) (mouseY / FixedWidthFontRenderer.FONT_HEIGHT);
-                m_focus = true;
+            charX = Math.min( Math.max( charX, 0 ), term.getWidth() - 1 );
-            }
+            charY = Math.min( Math.max( charY, 0 ), term.getHeight() - 1 );
 
-            if( m_focus )
+            computer.mouseDrag( button + 1, charX + 1, charY + 1 );
-            {
-                IComputer computer = m_computer.getComputer();
-                if( computer != null && computer.isColour() && button >= 0 && button <= 2 )
-                {
-                    Terminal term = computer.getTerminal();
-                    if( term != null )
-                    {
-                        int charX = (mouseX - (getXPosition() + m_leftMargin)) / FixedWidthFontRenderer.FONT_WIDTH;
-                        int charY = (mouseY - (getYPosition() + m_topMargin)) / FixedWidthFontRenderer.FONT_HEIGHT;
-                        charX = Math.min( Math.max( charX, 0 ), term.getWidth() - 1 );
-                        charY = Math.min( Math.max( charY, 0 ), term.getHeight() - 1 );
 
-                        computer.queueEvent( "mouse_click", new Object[] {
+            lastMouseX = charX;
-                            button + 1, charX + 1, charY + 1
+            lastMouseY = charY;
-                        } );
+            lastMouseButton = button;
-
-                        m_lastClickButton = button;
-                        m_lastClickX = charX;
-                        m_lastClickY = charY;
-                    }
-                }
-            }
-        }
-        else
-        {
-            if( m_focus && button == 0 && m_allowFocusLoss )
-            {
-                m_focus = false;
-            }
         }
+
+        return false;
     }
 
     @Override
-    public boolean onKeyboardInput()
+    public boolean mouseScrolled( double delta )
     {
-        boolean handled = false;
+        ClientComputer computer = this.computer.get();
-        for( int i = m_keysDown.size() - 1; i >= 0; --i )
+        if( computer == null || !computer.isColour() ) return false;
+
+        if( lastMouseX >= 0 && lastMouseY >= 0 && delta != 0 )
         {
-            int key = m_keysDown.get( i );
+            queueEvent( "mouse_scroll", delta < 0 ? 1 : -1, lastMouseX + 1, lastMouseY + 1 );
-            if( !Keyboard.isKeyDown( key ) )
-            {
-                m_keysDown.remove( i );
-                if( m_focus )
-                {
-                    // Queue the "key_up" event
-                    queueEvent( "key_up", new Object[] {
-                        key
-                    } );
-                    handled = true;
-                }
-            }
         }
 
-        return handled;
+        return true;
     }
 
-    @Override
-    public void handleMouseInput( int mouseX, int mouseY )
-    {
-        IComputer computer = m_computer.getComputer();
-        if( mouseX >= getXPosition() && mouseX < getXPosition() + getWidth() &&
-            mouseY >= getYPosition() && mouseY < getYPosition() + getHeight() &&
-            computer != null && computer.isColour() )
-        {
-            Terminal term = computer.getTerminal();
-            if( term != null )
-            {
-                int charX = (mouseX - (getXPosition() + m_leftMargin)) / FixedWidthFontRenderer.FONT_WIDTH;
-                int charY = (mouseY - (getYPosition() + m_topMargin)) / FixedWidthFontRenderer.FONT_HEIGHT;
-                charX = Math.min( Math.max( charX, 0 ), term.getWidth() - 1 );
-                charY = Math.min( Math.max( charY, 0 ), term.getHeight() - 1 );
-
-                if( m_lastClickButton >= 0 && !Mouse.isButtonDown( m_lastClickButton ) )
-                {
-                    if( m_focus )
-                    {
-                        computer.queueEvent( "mouse_up", new Object[] {
-                            m_lastClickButton + 1, charX + 1, charY + 1
-                        } );
-                    }
-                    m_lastClickButton = -1;
-                }
-
-                int wheelChange = Mouse.getEventDWheel();
-                if( wheelChange == 0 && m_lastClickButton == -1 )
-                {
-                    return;
-                }
-
-                if( m_focus )
-                {
-                    if( wheelChange < 0 )
-                    {
-                        computer.queueEvent( "mouse_scroll", new Object[] {
-                            1, charX + 1, charY + 1
-                        } );
-                    }
-                    else if( wheelChange > 0 )
-                    {
-                        computer.queueEvent( "mouse_scroll", new Object[] {
-                            -1, charX + 1, charY + 1
-                        } );
-                    }
-
-                    if( m_lastClickButton >= 0 && (charX != m_lastClickX || charY != m_lastClickY) )
-                    {
-                        computer.queueEvent( "mouse_drag", new Object[] {
-                            m_lastClickButton + 1, charX + 1, charY + 1
-                        } );
-                        m_lastClickX = charX;
-                        m_lastClickY = charY;
-                    }
-                }
-            }
-        }
-    }
-
-    @Override
     public void update()
     {
-        // Handle special keys
+        if( terminateTimer >= 0 && terminateTimer < TERMINATE_TIME && (terminateTimer += 0.05f) > TERMINATE_TIME )
-        if( m_focus && (Keyboard.isKeyDown( 29 ) || Keyboard.isKeyDown( 157 )) )
         {
-            // Ctrl+T for terminate
+            queueEvent( "terminate" );
-            if( Keyboard.isKeyDown( 20 ) )
-            {
-                if( m_terminateTimer < TERMINATE_TIME )
-                {
-                    m_terminateTimer = m_terminateTimer + 0.05f;
-                    if( m_terminateTimer >= TERMINATE_TIME )
-                    {
-                        queueEvent( "terminate" );
-                    }
-                }
-            }
-            else
-            {
-                m_terminateTimer = 0.0f;
-            }
-
-            // Ctrl+R for reboot
-            if( Keyboard.isKeyDown( 19 ) )
-            {
-                if( m_rebootTimer < TERMINATE_TIME )
-                {
-                    m_rebootTimer = m_rebootTimer + 0.05f;
-                    if( m_rebootTimer >= TERMINATE_TIME )
-                    {
-                        IComputer computer = m_computer.getComputer();
-                        if( computer != null )
-                        {
-                            computer.reboot();
-                        }
-                    }
-                }
-            }
-            else
-            {
-                m_rebootTimer = 0.0f;
-            }
-
-            // Ctrl+S for shutdown
-            if( Keyboard.isKeyDown( 31 ) )
-            {
-                if( m_shutdownTimer < TERMINATE_TIME )
-                {
-                    m_shutdownTimer = m_shutdownTimer + 0.05f;
-                    if( m_shutdownTimer >= TERMINATE_TIME )
-                    {
-                        IComputer computer = m_computer.getComputer();
-                        if( computer != null )
-                        {
-                            computer.shutdown();
-                        }
-                    }
-                }
-            }
-            else
-            {
-                m_shutdownTimer = 0.0f;
-            }
         }
-        else
+
+        if( shutdownTimer >= 0 && shutdownTimer < TERMINATE_TIME && (shutdownTimer += 0.05f) > TERMINATE_TIME )
         {
-            m_terminateTimer = 0.0f;
+            ClientComputer computer = this.computer.get();
-            m_rebootTimer = 0.0f;
+            if( computer != null ) computer.shutdown();
-            m_shutdownTimer = 0.0f;
+        }
+
+        if( rebootTimer >= 0 && rebootTimer < TERMINATE_TIME && (rebootTimer += 0.05f) > TERMINATE_TIME )
+        {
+            ClientComputer computer = this.computer.get();
+            if( computer != null ) computer.reboot();
         }
     }
 
     @Override
-    public void draw( Minecraft mc, int xOrigin, int yOrigin, int mouseX, int mouseY )
+    public void focusChanged( boolean focused )
     {
-        int startX = xOrigin + getXPosition();
+        if( !focused )
-        int startY = yOrigin + getYPosition();
+        {
+            // When blurring, we should make all keys go up
+            for( int key = 0; key < keysDown.size(); key++ )
+            {
+                if( keysDown.get( key ) ) queueEvent( "key_up", key );
+            }
+            keysDown.clear();
 
-        synchronized( m_computer )
+            // When blurring, we should make the last mouse button go up
+            if( lastMouseButton > 0 )
+            {
+                IComputer computer = this.computer.get();
+                if( computer != null ) computer.mouseUp( lastMouseButton + 1, lastMouseX + 1, lastMouseY + 1 );
+                lastMouseButton = -1;
+            }
+
+            shutdownTimer = terminateTimer = rebootTimer = -1;
+        }
+    }
+
+    public void draw( int originX, int originY )
+    {
+        synchronized( computer )
         {
             // Draw the screen contents
-            IComputer computer = m_computer.getComputer();
+            ClientComputer computer = this.computer.get();
-            Terminal terminal = (computer != null) ? computer.getTerminal() : null;
+            Terminal terminal = computer != null ? computer.getTerminal() : null;
             if( terminal != null )
             {
                 // Draw the terminal
                 boolean greyscale = !computer.isColour();
-
                 Palette palette = terminal.getPalette();
 
                 // Get the data from the terminal first
                 // Unfortunately we have to keep the lock for the whole of drawing, so the text doesn't change under us.
                 FixedWidthFontRenderer fontRenderer = FixedWidthFontRenderer.instance();
-                boolean tblink = m_focus && terminal.getCursorBlink() && FrameInfo.getGlobalCursorBlink();
+                boolean tblink = terminal.getCursorBlink() && FrameInfo.getGlobalCursorBlink();
                 int tw = terminal.getWidth();
                 int th = terminal.getHeight();
                 int tx = terminal.getCursorX();
                 int ty = terminal.getCursorY();
 
-                int x = startX + m_leftMargin;
-                int y = startY + m_topMargin;
-
                 // Draw margins
                 TextBuffer emptyLine = new TextBuffer( ' ', tw );
-                if( m_topMargin > 0 )
+                if( topMargin > 0 )
                 {
-                    fontRenderer.drawString( emptyLine, x, startY, terminal.getTextColourLine( 0 ), terminal.getBackgroundColourLine( 0 ), m_leftMargin, m_rightMargin, greyscale, palette );
+                    fontRenderer.drawString( emptyLine, originX, originY - topMargin,
+                        terminal.getTextColourLine( 0 ), terminal.getBackgroundColourLine( 0 ),
+                        leftMargin, rightMargin, greyscale, palette );
                 }
-                if( m_bottomMargin > 0 )
+
+                if( bottomMargin > 0 )
                 {
-                    fontRenderer.drawString( emptyLine, x, startY + 2 * m_bottomMargin + (th - 1) * FixedWidthFontRenderer.FONT_HEIGHT, terminal.getTextColourLine( th - 1 ), terminal.getBackgroundColourLine( th - 1 ), m_leftMargin, m_rightMargin, greyscale, palette );
+                    fontRenderer.drawString( emptyLine, originX, originY + bottomMargin + (th - 1) * FixedWidthFontRenderer.FONT_HEIGHT,
+                        terminal.getTextColourLine( th - 1 ), terminal.getBackgroundColourLine( th - 1 ),
+                        leftMargin, rightMargin, greyscale, palette );
                 }
 
                 // Draw lines
+                int y = originY;
                 for( int line = 0; line < th; line++ )
                 {
                     TextBuffer text = terminal.getLine( line );
                     TextBuffer colour = terminal.getTextColourLine( line );
                     TextBuffer backgroundColour = terminal.getBackgroundColourLine( line );
-                    fontRenderer.drawString( text, x, y, colour, backgroundColour, m_leftMargin, m_rightMargin, greyscale, palette );
+                    fontRenderer.drawString( text, originX, y, colour, backgroundColour, leftMargin, rightMargin, greyscale, palette );
                     y += FixedWidthFontRenderer.FONT_HEIGHT;
                 }
 
@@ -425,8 +363,8 @@ public class WidgetTerminal extends Widget
 
                     fontRenderer.drawString(
                         cursor,
-                        x + FixedWidthFontRenderer.FONT_WIDTH * tx,
+                        originX + FixedWidthFontRenderer.FONT_WIDTH * tx,
-                        startY + m_topMargin + FixedWidthFontRenderer.FONT_HEIGHT * ty,
+                        originY + FixedWidthFontRenderer.FONT_HEIGHT * ty,
                         cursorColour, null,
                         0, 0,
                         greyscale,
@@ -437,16 +375,29 @@ public class WidgetTerminal extends Widget
             else
             {
                 // Draw a black background
-                mc.getTextureManager().bindTexture( BACKGROUND );
                 Colour black = Colour.Black;
-                GlStateManager.color( black.getR(), black.getG(), black.getB(), 1.0f );
+                GlStateManager.color4f( black.getR(), black.getG(), black.getB(), 1.0f );
                 try
                 {
-                    drawTexturedModalRect( startX, startY, 0, 0, getWidth(), getHeight() );
+                    int x = originX - leftMargin;
+                    int y = originY - rightMargin;
+                    int width = termWidth * FixedWidthFontRenderer.FONT_WIDTH + leftMargin + rightMargin;
+                    int height = termHeight * FixedWidthFontRenderer.FONT_HEIGHT + topMargin + bottomMargin;
+
+                    client.getTextureManager().bindTexture( BACKGROUND );
+
+                    Tessellator tesslector = Tessellator.getInstance();
+                    BufferBuilder buffer = tesslector.getBuffer();
+                    buffer.begin( GL11.GL_QUADS, DefaultVertexFormats.POSITION_TEX );
+                    buffer.pos( x, y + height, 0 ).tex( 0 / 256.0, height / 256.0 ).endVertex();
+                    buffer.pos( x + width, y + height, 0 ).tex( width / 256.0, height / 256.0 ).endVertex();
+                    buffer.pos( x + width, y, 0 ).tex( width / 256.0, 0 / 256.0 ).endVertex();
+                    buffer.pos( x, y, 0 ).tex( 0 / 256.0, 0 / 256.0 ).endVertex();
+                    tesslector.draw();
                 }
                 finally
                 {
-                    GlStateManager.color( 1.0f, 1.0f, 1.0f, 1.0f );
+                    GlStateManager.color4f( 1.0f, 1.0f, 1.0f, 1.0f );
                 }
             }
         }
@@ -454,19 +405,13 @@ public class WidgetTerminal extends Widget
 
     private void queueEvent( String event )
     {
-        IComputer computer = m_computer.getComputer();
+        ClientComputer computer = this.computer.get();
-        if( computer != null )
+        if( computer != null ) computer.queueEvent( event );
-        {
-            computer.queueEvent( event );
-        }
     }
 
-    private void queueEvent( String event, Object[] args )
+    private void queueEvent( String event, Object... args )
     {
-        IComputer computer = m_computer.getComputer();
+        ClientComputer computer = this.computer.get();
-        if( computer != null )
+        if( computer != null ) computer.queueEvent( event, args );
-        {
-            computer.queueEvent( event, args );
-        }
     }
 }

src/main/java/dan200/computercraft/client/gui/widgets/WidgetWrapper.java

@@ -0,0 +1,104 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+
+package dan200.computercraft.client.gui.widgets;
+
+import net.minecraft.client.gui.IGuiEventListener;
+
+public class WidgetWrapper implements IGuiEventListener
+{
+    private final IGuiEventListener listener;
+    private final int x;
+    private final int y;
+    private final int width;
+    private final int height;
+
+    public WidgetWrapper( IGuiEventListener listener, int x, int y, int width, int height )
+    {
+        this.listener = listener;
+        this.x = x;
+        this.y = y;
+        this.width = width;
+        this.height = height;
+    }
+
+    @Override
+    public void focusChanged( boolean b )
+    {
+        listener.focusChanged( b );
+    }
+
+    @Override
+    public boolean canFocus()
+    {
+        return listener.canFocus();
+    }
+
+    @Override
+    public boolean mouseClicked( double x, double y, int button )
+    {
+        double dx = x - this.x, dy = y - this.y;
+        return dx >= 0 && dx < width && dy >= 0 && dy < height && listener.mouseClicked( dx, dy, button );
+    }
+
+    @Override
+    public boolean mouseReleased( double x, double y, int button )
+    {
+        double dx = x - this.x, dy = y - this.y;
+        return dx >= 0 && dx < width && dy >= 0 && dy < height && listener.mouseReleased( dx, dy, button );
+    }
+
+    @Override
+    public boolean mouseDragged( double x, double y, int button, double deltaX, double deltaY )
+    {
+        double dx = x - this.x, dy = y - this.y;
+        return dx >= 0 && dx < width && dy >= 0 && dy < height && listener.mouseDragged( dx, dy, button, deltaX, deltaY );
+    }
+
+    @Override
+    public boolean mouseScrolled( double delta )
+    {
+        return listener.mouseScrolled( delta );
+    }
+
+    @Override
+    public boolean keyPressed( int key, int scancode, int modifiers )
+    {
+        return listener.keyPressed( key, scancode, modifiers );
+    }
+
+    @Override
+    public boolean keyReleased( int key, int scancode, int modifiers )
+    {
+        return listener.keyReleased( key, scancode, modifiers );
+    }
+
+    @Override
+    public boolean charTyped( char character, int modifiers )
+    {
+        return listener.charTyped( character, modifiers );
+    }
+
+    public int getX()
+    {
+        return x;
+    }
+
+    public int getY()
+    {
+        return y;
+    }
+
+    public int getWidth()
+    {
+        return width;
+    }
+
+    public int getHeight()
+    {
+        return height;
+    }
+}

src/main/java/dan200/computercraft/client/proxy/CCTurtleProxyClient.java

@@ -1,24 +0,0 @@
-/*
- * This file is part of ComputerCraft - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
- * Send enquiries to dratcliffe@gmail.com
- */
-
-package dan200.computercraft.client.proxy;
-
-import dan200.computercraft.client.render.TileEntityTurtleRenderer;
-import dan200.computercraft.shared.proxy.CCTurtleProxyCommon;
-import dan200.computercraft.shared.turtle.blocks.TileTurtle;
-import net.minecraftforge.fml.client.registry.ClientRegistry;
-
-public class CCTurtleProxyClient extends CCTurtleProxyCommon
-{
-    @Override
-    public void init()
-    {
-        super.init();
-
-        // Setup renderers
-        ClientRegistry.bindTileEntitySpecialRenderer( TileTurtle.class, new TileEntityTurtleRenderer() );
-    }
-}

src/main/java/dan200/computercraft/client/proxy/ComputerCraftProxyClient.java

@@ -7,53 +7,90 @@
 package dan200.computercraft.client.proxy;
 
 import dan200.computercraft.ComputerCraft;
+import dan200.computercraft.client.gui.*;
 import dan200.computercraft.client.render.TileEntityCableRenderer;
 import dan200.computercraft.client.render.TileEntityMonitorRenderer;
-import dan200.computercraft.shared.command.CommandCopy;
+import dan200.computercraft.client.render.TileEntityTurtleRenderer;
+import dan200.computercraft.shared.computer.blocks.TileComputer;
+import dan200.computercraft.shared.computer.core.ClientComputer;
+import dan200.computercraft.shared.computer.inventory.ContainerViewComputer;
+import dan200.computercraft.shared.network.container.*;
 import dan200.computercraft.shared.peripheral.modem.wired.TileCable;
 import dan200.computercraft.shared.peripheral.monitor.ClientMonitor;
 import dan200.computercraft.shared.peripheral.monitor.TileMonitor;
-import dan200.computercraft.shared.proxy.ComputerCraftProxyCommon;
+import dan200.computercraft.shared.turtle.blocks.TileTurtle;
-import net.minecraftforge.client.ClientCommandHandler;
+import dan200.computercraft.shared.turtle.inventory.ContainerTurtle;
+import net.minecraft.client.Minecraft;
+import net.minecraft.client.gui.inventory.GuiContainer;
+import net.minecraft.entity.player.EntityPlayer;
+import net.minecraftforge.api.distmarker.Dist;
 import net.minecraftforge.event.world.WorldEvent;
+import net.minecraftforge.eventbus.api.SubscribeEvent;
+import net.minecraftforge.fml.ExtensionPoint;
+import net.minecraftforge.fml.ModLoadingContext;
 import net.minecraftforge.fml.client.registry.ClientRegistry;
 import net.minecraftforge.fml.common.Mod;
-import net.minecraftforge.fml.common.eventhandler.SubscribeEvent;
+import net.minecraftforge.fml.event.lifecycle.FMLClientSetupEvent;
-import net.minecraftforge.fml.relauncher.Side;
 
-public class ComputerCraftProxyClient extends ComputerCraftProxyCommon
+import java.util.function.BiFunction;
+
+@Mod.EventBusSubscriber( modid = ComputerCraft.MOD_ID, value = Dist.CLIENT, bus = Mod.EventBusSubscriber.Bus.MOD )
+public final class ComputerCraftProxyClient
 {
-    @Override
+    @SubscribeEvent
-    public void preInit()
+    public static void setupClient( FMLClientSetupEvent event )
     {
-        super.preInit();
+        registerContainers();
 
-        // Register any client-specific commands
+        // Setup TESRs
-        ClientCommandHandler.instance.registerCommand( CommandCopy.INSTANCE );
-    }
-
-    @Override
-    public void init()
-    {
-        super.init();
-
-        // Setup renderers
         ClientRegistry.bindTileEntitySpecialRenderer( TileMonitor.class, new TileEntityMonitorRenderer() );
         ClientRegistry.bindTileEntitySpecialRenderer( TileCable.class, new TileEntityCableRenderer() );
+        ClientRegistry.bindTileEntitySpecialRenderer( TileTurtle.class, new TileEntityTurtleRenderer() );
     }
 
-    @Mod.EventBusSubscriber( modid = ComputerCraft.MOD_ID, value = Side.CLIENT )
+    private static void registerContainers()
-    public static class ForgeHandlers
+    {
+        ContainerType.registerGui( TileEntityContainerType::computer, ( packet, player ) ->
+            new GuiComputer( (TileComputer) packet.getTileEntity( player ) ) );
+        ContainerType.registerGui( TileEntityContainerType::diskDrive, GuiDiskDrive::new );
+        ContainerType.registerGui( TileEntityContainerType::printer, GuiPrinter::new );
+        ContainerType.registerGui( TileEntityContainerType::turtle, ( packet, player ) -> {
+            TileTurtle turtle = (TileTurtle) packet.getTileEntity( player );
+            return new GuiTurtle( turtle, new ContainerTurtle( player.inventory, turtle.getAccess(), turtle.getClientComputer() ) );
+        } );
+
+        ContainerType.registerGui( PocketComputerContainerType::new, GuiPocketComputer::new );
+        ContainerType.registerGui( PrintoutContainerType::new, GuiPrintout::new );
+        ContainerType.registerGui( ViewComputerContainerType::new, ( packet, player ) -> {
+            ClientComputer computer = ComputerCraft.clientComputerRegistry.get( packet.instanceId );
+            if( computer == null )
+            {
+                ComputerCraft.clientComputerRegistry.add( packet.instanceId, computer = new ClientComputer( packet.instanceId ) );
+            }
+
+            ContainerViewComputer container = new ContainerViewComputer( computer );
+            return new GuiComputer( container, packet.family, computer, packet.width, packet.height );
+        } );
+
+        ModLoadingContext.get().registerExtensionPoint( ExtensionPoint.GUIFACTORY, () -> packet -> {
+            ContainerType<?> type = ContainerType.factories.get( packet.getId() ).get();
+            if( packet.getAdditionalData() != null ) type.fromBytes( packet.getAdditionalData() );
+            @SuppressWarnings( "unchecked" )
+            BiFunction<ContainerType<?>, EntityPlayer, GuiContainer> factory = (BiFunction<ContainerType<?>, EntityPlayer, GuiContainer>) ContainerType.guiFactories.get( packet.getId() );
+            return factory.apply( type, Minecraft.getInstance().player );
+        } );
+    }
+
+    @Mod.EventBusSubscriber( modid = ComputerCraft.MOD_ID, value = Dist.CLIENT )
+    public static final class ForgeHandlers
     {
         @SubscribeEvent
         public static void onWorldUnload( WorldEvent.Unload event )
         {
-            if( event.getWorld().isRemote )
+            if( event.getWorld().isRemote() )
             {
                 ClientMonitor.destroyAll();
             }
         }
     }
-
-
 }

src/main/java/dan200/computercraft/client/render/ItemMapLikeRenderer.java

@@ -7,8 +7,8 @@
 package dan200.computercraft.client.render;
 
 import net.minecraft.client.Minecraft;
+import net.minecraft.client.renderer.FirstPersonRenderer;
 import net.minecraft.client.renderer.GlStateManager;
-import net.minecraft.client.renderer.ItemRenderer;
 import net.minecraft.entity.player.EntityPlayer;
 import net.minecraft.item.ItemStack;
 import net.minecraft.util.EnumHand;
@@ -21,13 +21,13 @@ public abstract class ItemMapLikeRenderer
      * The main rendering method for the item
      *
      * @param stack The stack to render
-     * @see ItemRenderer#renderMapFirstPerson(ItemStack)
+     * @see FirstPersonRenderer#renderMapFirstPerson(ItemStack)
      */
     protected abstract void renderItem( ItemStack stack );
 
     protected void renderItemFirstPerson( EnumHand hand, float pitch, float equipProgress, float swingProgress, ItemStack stack )
     {
-        EntityPlayer player = Minecraft.getMinecraft().player;
+        EntityPlayer player = Minecraft.getInstance().player;
 
         GlStateManager.pushMatrix();
         if( hand == EnumHand.MAIN_HAND && player.getHeldItemOffhand().isEmpty() )
@@ -51,35 +51,35 @@ public abstract class ItemMapLikeRenderer
      * @param equipProgress The equip progress of this item
      * @param swingProgress The swing progress of this item
      * @param stack         The stack to render
-     * @see ItemRenderer#renderMapFirstPersonSide(float, EnumHandSide, float, ItemStack)
+     * @see FirstPersonRenderer#renderMapFirstPersonSide(float, EnumHandSide, float, ItemStack)
      */
     private void renderItemFirstPersonSide( EnumHandSide side, float equipProgress, float swingProgress, ItemStack stack )
     {
-        Minecraft minecraft = Minecraft.getMinecraft();
+        Minecraft minecraft = Minecraft.getInstance();
         float offset = side == EnumHandSide.RIGHT ? 1f : -1f;
-        GlStateManager.translate( offset * 0.125f, -0.125f, 0f );
+        GlStateManager.translatef( offset * 0.125f, -0.125f, 0f );
 
         // If the player is not invisible then render a single arm
         if( !minecraft.player.isInvisible() )
         {
             GlStateManager.pushMatrix();
-            GlStateManager.rotate( offset * 10f, 0f, 0f, 1f );
+            GlStateManager.rotatef( offset * 10f, 0f, 0f, 1f );
-            minecraft.getItemRenderer().renderArmFirstPerson( equipProgress, swingProgress, side );
+            minecraft.getFirstPersonRenderer().renderArmFirstPerson( equipProgress, swingProgress, side );
             GlStateManager.popMatrix();
         }
 
         // Setup the appropriate transformations. This is just copied from the
         // corresponding method in ItemRenderer.
         GlStateManager.pushMatrix();
-        GlStateManager.translate( offset * 0.51f, -0.08f + equipProgress * -1.2f, -0.75f );
+        GlStateManager.translatef( offset * 0.51f, -0.08f + equipProgress * -1.2f, -0.75f );
         float f1 = MathHelper.sqrt( swingProgress );
         float f2 = MathHelper.sin( f1 * (float) Math.PI );
         float f3 = -0.5f * f2;
         float f4 = 0.4f * MathHelper.sin( f1 * ((float) Math.PI * 2f) );
         float f5 = -0.3f * MathHelper.sin( swingProgress * (float) Math.PI );
-        GlStateManager.translate( offset * f3, f4 - 0.3f * f2, f5 );
+        GlStateManager.translatef( offset * f3, f4 - 0.3f * f2, f5 );
-        GlStateManager.rotate( f2 * -45f, 1f, 0f, 0f );
+        GlStateManager.rotatef( f2 * -45f, 1f, 0f, 0f );
-        GlStateManager.rotate( offset * f2 * -30f, 0f, 1f, 0f );
+        GlStateManager.rotatef( offset * f2 * -30f, 0f, 1f, 0f );
 
         renderItem( stack );
 
@@ -93,25 +93,25 @@ public abstract class ItemMapLikeRenderer
      * @param equipProgress The equip progress of this item
      * @param swingProgress The swing progress of this item
      * @param stack         The stack to render
-     * @see ItemRenderer#renderMapFirstPerson(float, float, float)
+     * @see FirstPersonRenderer#renderMapFirstPerson(float, float, float)
      */
     private void renderItemFirstPersonCenter( float pitch, float equipProgress, float swingProgress, ItemStack stack )
     {
-        ItemRenderer itemRenderer = Minecraft.getMinecraft().getItemRenderer();
+        FirstPersonRenderer renderer = Minecraft.getInstance().getFirstPersonRenderer();
 
         // Setup the appropriate transformations. This is just copied from the
         // corresponding method in ItemRenderer.
         float swingRt = MathHelper.sqrt( swingProgress );
         float tX = -0.2f * MathHelper.sin( swingProgress * (float) Math.PI );
         float tZ = -0.4f * MathHelper.sin( swingRt * (float) Math.PI );
-        GlStateManager.translate( 0f, -tX / 2f, tZ );
+        GlStateManager.translatef( 0f, -tX / 2f, tZ );
-        float pitchAngle = itemRenderer.getMapAngleFromPitch( pitch );
+        float pitchAngle = renderer.getMapAngleFromPitch( pitch );
-        GlStateManager.translate( 0f, 0.04f + equipProgress * -1.2f + pitchAngle * -0.5f, -0.72f );
+        GlStateManager.translatef( 0f, 0.04f + equipProgress * -1.2f + pitchAngle * -0.5f, -0.72f );
-        GlStateManager.rotate( pitchAngle * -85f, 1f, 0f, 0f );
+        GlStateManager.rotatef( pitchAngle * -85f, 1f, 0f, 0f );
-        itemRenderer.renderArms();
+        renderer.renderArms();
         float rX = MathHelper.sin( swingRt * (float) Math.PI );
-        GlStateManager.rotate( rX * 20f, 1f, 0f, 0f );
+        GlStateManager.rotatef( rX * 20f, 1f, 0f, 0f );
-        GlStateManager.scale( 2f, 2f, 2f );
+        GlStateManager.scalef( 2f, 2f, 2f );
 
         renderItem( stack );
     }

src/main/java/dan200/computercraft/client/render/ItemPocketRenderer.java

@@ -16,17 +16,16 @@ import dan200.computercraft.shared.pocket.items.ItemPocketComputer;
 import dan200.computercraft.shared.util.Palette;
 import net.minecraft.client.Minecraft;
 import net.minecraft.client.renderer.GlStateManager;
-import net.minecraft.client.renderer.RenderItem;
+import net.minecraft.client.renderer.ItemRenderer;
-import net.minecraft.client.renderer.block.model.IBakedModel;
+import net.minecraft.client.renderer.model.IBakedModel;
-import net.minecraft.client.renderer.block.model.ItemCameraTransforms;
 import net.minecraft.client.renderer.texture.TextureManager;
 import net.minecraft.client.renderer.texture.TextureMap;
 import net.minecraft.item.ItemStack;
+import net.minecraftforge.api.distmarker.Dist;
 import net.minecraftforge.client.ForgeHooksClient;
 import net.minecraftforge.client.event.RenderSpecificHandEvent;
+import net.minecraftforge.eventbus.api.SubscribeEvent;
 import net.minecraftforge.fml.common.Mod;
-import net.minecraftforge.fml.common.eventhandler.SubscribeEvent;
-import net.minecraftforge.fml.relauncher.Side;
 import org.lwjgl.opengl.GL11;
 
 import static dan200.computercraft.client.gui.FixedWidthFontRenderer.FONT_HEIGHT;
@@ -35,7 +34,7 @@ import static dan200.computercraft.client.gui.FixedWidthFontRenderer.FONT_WIDTH;
 /**
  * Emulates map rendering for pocket computers
  */
-@Mod.EventBusSubscriber( modid = ComputerCraft.MOD_ID, value = Side.CLIENT )
+@Mod.EventBusSubscriber( modid = ComputerCraft.MOD_ID, value = Dist.CLIENT )
 public final class ItemPocketRenderer extends ItemMapLikeRenderer
 {
     private static final ItemPocketRenderer INSTANCE = new ItemPocketRenderer();
@@ -57,44 +56,41 @@ public final class ItemPocketRenderer extends ItemMapLikeRenderer
     @Override
     protected void renderItem( ItemStack stack )
     {
-        // Setup various transformations. Note that these are partially adapated from the corresponding method
+        // Setup various transformations. Note that these are partially adapted from the corresponding method
         // in ItemRenderer
         GlStateManager.disableLighting();
 
-        GlStateManager.rotate( 180f, 0f, 1f, 0f );
+        GlStateManager.rotatef( 180f, 0f, 1f, 0f );
-        GlStateManager.rotate( 180f, 0f, 0f, 1f );
+        GlStateManager.rotatef( 180f, 0f, 0f, 1f );
-        GlStateManager.scale( 0.5, 0.5, 0.5 );
+        GlStateManager.scalef( 0.5f, 0.5f, 0.5f );
 
-        ItemPocketComputer pocketComputer = ComputerCraft.Items.pocketComputer;
+        ClientComputer computer = ItemPocketComputer.createClientComputer( stack );
-        ClientComputer computer = pocketComputer.createClientComputer( stack );
 
         {
             // First render the background item. We use the item's model rather than a direct texture as this ensures
             // we display the pocket light and other such decorations.
             GlStateManager.pushMatrix();
 
-            GlStateManager.scale( 1.0f, -1.0f, 1.0f );
+            GlStateManager.scalef( 1.0f, -1.0f, 1.0f );
 
-            Minecraft minecraft = Minecraft.getMinecraft();
+            Minecraft minecraft = Minecraft.getInstance();
             TextureManager textureManager = minecraft.getTextureManager();
-            RenderItem renderItem = minecraft.getRenderItem();
+            ItemRenderer renderItem = minecraft.getItemRenderer();
 
             // Copy of RenderItem#renderItemModelIntoGUI but without the translation or scaling
             textureManager.bindTexture( TextureMap.LOCATION_BLOCKS_TEXTURE );
             textureManager.getTexture( TextureMap.LOCATION_BLOCKS_TEXTURE ).setBlurMipmap( false, false );
 
             GlStateManager.enableRescaleNormal();
-            GlStateManager.enableAlpha();
+            GlStateManager.enableAlphaTest();
             GlStateManager.alphaFunc( GL11.GL_GREATER, 0.1F );
             GlStateManager.enableBlend();
             GlStateManager.blendFunc( GlStateManager.SourceFactor.SRC_ALPHA, GlStateManager.DestFactor.ONE_MINUS_SRC_ALPHA );
-            GlStateManager.color( 1.0F, 1.0F, 1.0F, 1.0F );
+            GlStateManager.color4f( 1.0F, 1.0F, 1.0F, 1.0F );
 
-            IBakedModel bakedmodel = renderItem.getItemModelWithOverrides( stack, null, null );
+            renderItem.renderItem( stack, transform( renderItem.getItemModelWithOverrides( stack, null, null ) ) );
-            bakedmodel = ForgeHooksClient.handleCameraTransforms( bakedmodel, ItemCameraTransforms.TransformType.GUI, false );
-            renderItem.renderItem( stack, bakedmodel );
 
-            GlStateManager.disableAlpha();
+            GlStateManager.disableAlphaTest();
             GlStateManager.disableRescaleNormal();
 
             GlStateManager.popMatrix();
@@ -109,13 +105,13 @@ public final class ItemPocketRenderer extends ItemMapLikeRenderer
                 synchronized( terminal )
                 {
                     GlStateManager.pushMatrix();
-                    GlStateManager.disableDepth();
+                    GlStateManager.disableDepthTest();
 
                     // Reset the position to be at the top left corner of the pocket computer
                     // Note we translate towards the screen slightly too.
-                    GlStateManager.translate( -8 / 16.0, -8 / 16.0, 0.5 / 16.0 );
+                    GlStateManager.translated( -8 / 16.0, -8 / 16.0, 0.5 / 16.0 );
                     // Translate to the top left of the screen.
-                    GlStateManager.translate( 4 / 16.0, 3 / 16.0, 0 );
+                    GlStateManager.translated( 4 / 16.0, 3 / 16.0, 0 );
 
                     // Work out the scaling required to resize the terminal in order to fit on the computer
                     final int margin = 2;
@@ -127,7 +123,7 @@ public final class ItemPocketRenderer extends ItemMapLikeRenderer
 
                     // The grid is 8 * 8 wide, so we start with a base of 1/2 (8 / 16).
                     double scale = 1.0 / 2.0 / max;
-                    GlStateManager.scale( scale, scale, scale );
+                    GlStateManager.scaled( scale, scale, scale );
 
                     // The margin/start positions are determined in order for the terminal to be centred.
                     int startX = (max - width) / 2 + margin;
@@ -161,7 +157,7 @@ public final class ItemPocketRenderer extends ItemMapLikeRenderer
                         );
                     }
 
-                    GlStateManager.enableDepth();
+                    GlStateManager.enableDepthTest();
                     GlStateManager.popMatrix();
                 }
             }
@@ -169,4 +165,10 @@ public final class ItemPocketRenderer extends ItemMapLikeRenderer
 
         GlStateManager.enableLighting();
     }
+
+    @SuppressWarnings( { "deprecation" } )
+    private static IBakedModel transform( IBakedModel model )
+    {
+        return ForgeHooksClient.handleCameraTransforms( model, net.minecraft.client.renderer.model.ItemCameraTransforms.TransformType.GUI, false );
+    }
 }

src/main/java/dan200/computercraft/client/render/ItemPrintoutRenderer.java

@@ -10,11 +10,11 @@ import dan200.computercraft.ComputerCraft;
 import dan200.computercraft.shared.media.items.ItemPrintout;
 import net.minecraft.client.renderer.GlStateManager;
 import net.minecraft.item.ItemStack;
+import net.minecraftforge.api.distmarker.Dist;
 import net.minecraftforge.client.event.RenderItemInFrameEvent;
 import net.minecraftforge.client.event.RenderSpecificHandEvent;
+import net.minecraftforge.eventbus.api.SubscribeEvent;
 import net.minecraftforge.fml.common.Mod;
-import net.minecraftforge.fml.common.eventhandler.SubscribeEvent;
-import net.minecraftforge.fml.relauncher.Side;
 
 import static dan200.computercraft.client.gui.FixedWidthFontRenderer.FONT_HEIGHT;
 import static dan200.computercraft.client.gui.FixedWidthFontRenderer.FONT_WIDTH;
@@ -23,9 +23,9 @@ import static dan200.computercraft.shared.media.items.ItemPrintout.LINES_PER_PAG
 import static dan200.computercraft.shared.media.items.ItemPrintout.LINE_MAX_LENGTH;
 
 /**
- * Emulates map and item-frame rendering for prinouts
+ * Emulates map and item-frame rendering for printouts
  */
-@Mod.EventBusSubscriber( modid = ComputerCraft.MOD_ID, value = Side.CLIENT )
+@Mod.EventBusSubscriber( modid = ComputerCraft.MOD_ID, value = Dist.CLIENT )
 public final class ItemPrintoutRenderer extends ItemMapLikeRenderer
 {
     private static final ItemPrintoutRenderer INSTANCE = new ItemPrintoutRenderer();
@@ -38,10 +38,9 @@ public final class ItemPrintoutRenderer extends ItemMapLikeRenderer
     public static void onRenderInHand( RenderSpecificHandEvent event )
     {
         ItemStack stack = event.getItemStack();
-        if( stack.getItem() != ComputerCraft.Items.printout ) return;
+        if( !(stack.getItem() instanceof ItemPrintout) ) return;
 
         event.setCanceled( true );
-
         INSTANCE.renderItemFirstPerson( event.getHand(), event.getInterpolatedPitch(), event.getEquipProgress(), event.getSwingProgress(), event.getItemStack() );
     }
 
@@ -49,13 +48,13 @@ public final class ItemPrintoutRenderer extends ItemMapLikeRenderer
     protected void renderItem( ItemStack stack )
     {
         // Setup various transformations. Note that these are partially adapated from the corresponding method
-        // in ItemRenderer.renderMapFirstPerson
+        // in FirstPersonRenderer.renderFirstPersonMap
         GlStateManager.disableLighting();
 
-        GlStateManager.rotate( 180f, 0f, 1f, 0f );
+        GlStateManager.rotatef( 180f, 0f, 1f, 0f );
-        GlStateManager.rotate( 180f, 0f, 0f, 1f );
+        GlStateManager.rotatef( 180f, 0f, 0f, 1f );
-        GlStateManager.scale( 0.42f, 0.42f, -0.42f );
+        GlStateManager.scalef( 0.42f, 0.42f, -0.42f );
-        GlStateManager.translate( -0.5f, -0.48f, 0.0f );
+        GlStateManager.translatef( -0.5f, -0.48f, 0.0f );
 
         drawPrintout( stack );
 
@@ -66,17 +65,17 @@ public final class ItemPrintoutRenderer extends ItemMapLikeRenderer
     public static void onRenderInFrame( RenderItemInFrameEvent event )
     {
         ItemStack stack = event.getItem();
-        if( stack.getItem() != ComputerCraft.Items.printout ) return;
+        if( !(stack.getItem() instanceof ItemPrintout) ) return;
 
         event.setCanceled( true );
 
         GlStateManager.disableLighting();
 
         // Move a little bit forward to ensure we're not clipping with the frame
-        GlStateManager.translate( 0.0f, 0.0f, -0.001f );
+        GlStateManager.translatef( 0.0f, 0.0f, -0.001f );
-        GlStateManager.rotate( 180f, 0f, 0f, 1f );
+        GlStateManager.rotatef( 180f, 0f, 0f, 1f );
-        GlStateManager.scale( 0.95f, 0.95f, -0.95f );
+        GlStateManager.scalef( 0.95f, 0.95f, -0.95f );
-        GlStateManager.translate( -0.5f, -0.5f, 0.0f );
+        GlStateManager.translatef( -0.5f, -0.5f, 0.0f );
 
         drawPrintout( stack );
 
@@ -87,7 +86,7 @@ public final class ItemPrintoutRenderer extends ItemMapLikeRenderer
     private static void drawPrintout( ItemStack stack )
     {
         int pages = ItemPrintout.getPageCount( stack );
-        boolean book = ItemPrintout.getType( stack ) == ItemPrintout.Type.Book;
+        boolean book = ((ItemPrintout) stack.getItem()).getType() == ItemPrintout.Type.BOOK;
 
         double width = LINE_MAX_LENGTH * FONT_WIDTH + X_TEXT_MARGIN * 2;
         double height = LINES_PER_PAGE * FONT_HEIGHT + Y_TEXT_MARGIN * 2;
@@ -108,8 +107,8 @@ public final class ItemPrintoutRenderer extends ItemMapLikeRenderer
 
         // Scale the printout to fit correctly.
         double scale = 1.0 / max;
-        GlStateManager.scale( scale, scale, scale );
+        GlStateManager.scaled( scale, scale, scale );
-        GlStateManager.translate( (max - width) / 2.0f, (max - height) / 2.0f, 0.0f );
+        GlStateManager.translated( (max - width) / 2.0, (max - height) / 2.0, 0.0 );
 
         drawBorder( 0, 0, -0.01, 0, pages, book );
         drawText( X_TEXT_MARGIN, Y_TEXT_MARGIN, 0, ItemPrintout.getText( stack ), ItemPrintout.getColours( stack ) );

src/main/java/dan200/computercraft/client/render/ModelTransformer.java

@@ -6,7 +6,7 @@
 
 package dan200.computercraft.client.render;
 
-import net.minecraft.client.renderer.block.model.BakedQuad;
+import net.minecraft.client.renderer.model.BakedQuad;
 import net.minecraft.client.renderer.texture.TextureAtlasSprite;
 import net.minecraft.client.renderer.vertex.VertexFormat;
 import net.minecraft.util.EnumFacing;
@@ -180,7 +180,7 @@ public final class ModelTransformer
      *
      * This also provides the ability to swap vertices through {@link #swap(int, int)} to allow reordering.
      */
-    private static class BakedQuadBuilder implements IVertexConsumer
+    private static final class BakedQuadBuilder implements IVertexConsumer
     {
         private final VertexFormat format;
 
@@ -195,7 +195,7 @@ public final class ModelTransformer
         private BakedQuadBuilder( VertexFormat format )
         {
             this.format = format;
-            this.vertexData = new int[format.getSize()];
+            vertexData = new int[format.getSize()];
         }
 
         @Nonnull
@@ -208,7 +208,7 @@ public final class ModelTransformer
         @Override
         public void setQuadTint( int tint )
         {
-            this.quadTint = tint;
+            quadTint = tint;
         }
 
         @Override

src/main/java/dan200/computercraft/client/render/PrintoutRenderer.java

@@ -12,6 +12,8 @@ import dan200.computercraft.shared.util.Palette;
 import net.minecraft.client.Minecraft;
 import net.minecraft.client.renderer.BufferBuilder;
 import net.minecraft.client.renderer.GlStateManager;
+import net.minecraft.client.renderer.GlStateManager.DestFactor;
+import net.minecraft.client.renderer.GlStateManager.SourceFactor;
 import net.minecraft.client.renderer.Tessellator;
 import net.minecraft.client.renderer.vertex.DefaultVertexFormats;
 import net.minecraft.util.ResourceLocation;
@@ -20,7 +22,7 @@ import org.lwjgl.opengl.GL11;
 import static dan200.computercraft.client.gui.FixedWidthFontRenderer.FONT_HEIGHT;
 import static dan200.computercraft.shared.media.items.ItemPrintout.LINES_PER_PAGE;
 
-public class PrintoutRenderer
+public final class PrintoutRenderer
 {
     private static final ResourceLocation BG = new ResourceLocation( "computercraft", "textures/gui/printout.png" );
     private static final double BG_SIZE = 256.0;
@@ -58,6 +60,8 @@ public class PrintoutRenderer
     private static final int COVER_Y = Y_SIZE;
     private static final int COVER_X = X_SIZE + 4 * X_FOLD_SIZE;
 
+    private PrintoutRenderer() {}
+
     public static void drawText( int x, int y, int start, TextBuffer[] text, TextBuffer[] colours )
     {
         FixedWidthFontRenderer fontRenderer = FixedWidthFontRenderer.instance();
@@ -70,9 +74,10 @@ public class PrintoutRenderer
 
     public static void drawText( int x, int y, int start, String[] text, String[] colours )
     {
-        GlStateManager.color( 1.0f, 1.0f, 1.0f, 1.0f );
+        GlStateManager.color4f( 1.0f, 1.0f, 1.0f, 1.0f );
         GlStateManager.enableBlend();
         GlStateManager.enableTexture2D();
+        GlStateManager.blendFuncSeparate( SourceFactor.SRC_ALPHA, DestFactor.ONE_MINUS_SRC_ALPHA, SourceFactor.ONE, DestFactor.ZERO );
 
         FixedWidthFontRenderer fontRenderer = FixedWidthFontRenderer.instance();
 
@@ -84,11 +89,12 @@ public class PrintoutRenderer
 
     public static void drawBorder( double x, double y, double z, int page, int pages, boolean isBook )
     {
-        GlStateManager.color( 1.0f, 1.0f, 1.0f, 1.0f );
+        GlStateManager.color4f( 1.0f, 1.0f, 1.0f, 1.0f );
         GlStateManager.enableBlend();
         GlStateManager.enableTexture2D();
+        GlStateManager.blendFuncSeparate( SourceFactor.SRC_ALPHA, DestFactor.ONE_MINUS_SRC_ALPHA, SourceFactor.ONE, DestFactor.ZERO );
 
-        Minecraft.getMinecraft().getTextureManager().bindTexture( BG );
+        Minecraft.getInstance().getTextureManager().bindTexture( BG );
 
         Tessellator tessellator = Tessellator.getInstance();
         BufferBuilder buffer = tessellator.getBuffer();

src/main/java/dan200/computercraft/client/render/RenderOverlayCable.java

@@ -7,216 +7,82 @@
 package dan200.computercraft.client.render;
 
 import dan200.computercraft.ComputerCraft;
-import dan200.computercraft.shared.peripheral.PeripheralType;
 import dan200.computercraft.shared.peripheral.modem.wired.BlockCable;
-import dan200.computercraft.shared.peripheral.modem.wired.CableBounds;
+import dan200.computercraft.shared.peripheral.modem.wired.CableShapes;
 import dan200.computercraft.shared.util.WorldUtil;
 import net.minecraft.block.state.IBlockState;
-import net.minecraft.client.renderer.BufferBuilder;
+import net.minecraft.client.Minecraft;
 import net.minecraft.client.renderer.GlStateManager;
-import net.minecraft.client.renderer.RenderGlobal;
+import net.minecraft.client.renderer.WorldRenderer;
-import net.minecraft.client.renderer.Tessellator;
-import net.minecraft.client.renderer.vertex.DefaultVertexFormats;
 import net.minecraft.entity.player.EntityPlayer;
-import net.minecraft.util.EnumFacing;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.util.math.RayTraceResult;
+import net.minecraft.util.math.shapes.VoxelShape;
 import net.minecraft.world.World;
+import net.minecraftforge.api.distmarker.Dist;
 import net.minecraftforge.client.event.DrawBlockHighlightEvent;
+import net.minecraftforge.eventbus.api.SubscribeEvent;
 import net.minecraftforge.fml.common.Mod;
-import net.minecraftforge.fml.common.eventhandler.SubscribeEvent;
-import net.minecraftforge.fml.relauncher.Side;
 import org.lwjgl.opengl.GL11;
 
-@Mod.EventBusSubscriber( modid = ComputerCraft.MOD_ID, value = Side.CLIENT )
+@Mod.EventBusSubscriber( modid = ComputerCraft.MOD_ID, value = Dist.CLIENT )
 public final class RenderOverlayCable
 {
-    private static final float EXPAND = 0.002f;
-    private static final double MIN = CableBounds.MIN - EXPAND;
-    private static final double MAX = CableBounds.MAX + EXPAND;
-
     private RenderOverlayCable()
     {
     }
 
+    /**
+     * Draw an outline for a specific part of a cable "Multipart".
+     *
+     * @param event The event to observe
+     * @see WorldRenderer#drawSelectionBox(EntityPlayer, RayTraceResult, int, float)
+     */
     @SubscribeEvent
     public static void drawHighlight( DrawBlockHighlightEvent event )
     {
-        if( event.getTarget().typeOfHit != RayTraceResult.Type.BLOCK ) return;
+        if( event.getTarget().type != RayTraceResult.Type.BLOCK ) return;
 
         BlockPos pos = event.getTarget().getBlockPos();
         World world = event.getPlayer().getEntityWorld();
 
         IBlockState state = world.getBlockState( pos );
-        if( state.getBlock() != ComputerCraft.Blocks.cable ) return;
 
-        state = state.getActualState( world, pos );
+        // We only care about instances with both cable and modem.
+        if( state.getBlock() != ComputerCraft.Blocks.cable || state.get( BlockCable.MODEM ).getFacing() == null || !state.get( BlockCable.CABLE ) )
+        {
+            return;
+        }
 
         event.setCanceled( true );
-        PeripheralType type = ComputerCraft.Blocks.cable.getPeripheralType( state );
+
+        EntityPlayer player = event.getPlayer();
+        Minecraft mc = Minecraft.getInstance();
+        float partialTicks = event.getPartialTicks();
 
         GlStateManager.enableBlend();
-        GlStateManager.tryBlendFuncSeparate( GL11.GL_SRC_ALPHA, GL11.GL_ONE_MINUS_SRC_ALPHA, 1, 0 );
+        GlStateManager.blendFuncSeparate( GlStateManager.SourceFactor.SRC_ALPHA, GlStateManager.DestFactor.ONE_MINUS_SRC_ALPHA, GlStateManager.SourceFactor.ONE, GlStateManager.DestFactor.ZERO );
-        GlStateManager.color( 0.0f, 0.0f, 0.0f, 0.4f );
+        GlStateManager.lineWidth( Math.max( 2.5F, mc.mainWindow.getFramebufferWidth() / 1920.0F * 2.5F ) );
-        GL11.glLineWidth( 2.0F );
         GlStateManager.disableTexture2D();
         GlStateManager.depthMask( false );
+        GlStateManager.matrixMode( GL11.GL_PROJECTION );
         GlStateManager.pushMatrix();
+        GlStateManager.scalef( 1.0F, 1.0F, 0.999F );
 
-        {
+        double x = player.lastTickPosX + (player.posX - player.lastTickPosX) * partialTicks;
-            EntityPlayer player = event.getPlayer();
+        double y = player.lastTickPosY + (player.posY - player.lastTickPosY) * partialTicks;
-            double x = player.lastTickPosX + (player.posX - player.lastTickPosX) * event.getPartialTicks();
+        double z = player.lastTickPosZ + (player.posZ - player.lastTickPosZ) * partialTicks;
-            double y = player.lastTickPosY + (player.posY - player.lastTickPosY) * event.getPartialTicks();
-            double z = player.lastTickPosZ + (player.posZ - player.lastTickPosZ) * event.getPartialTicks();
 
-            GlStateManager.translate( -x + pos.getX(), -y + pos.getY(), -z + pos.getZ() );
+        VoxelShape shape = WorldUtil.isVecInside( CableShapes.getModemShape( state ), event.getTarget().hitVec.subtract( pos.getX(), pos.getY(), pos.getZ() ) )
-        }
+            ? CableShapes.getModemShape( state )
+            : CableShapes.getCableShape( state );
 
-        if( type != PeripheralType.Cable && WorldUtil.isVecInsideInclusive( CableBounds.getModemBounds( state ), event.getTarget().hitVec.subtract( pos.getX(), pos.getY(), pos.getZ() ) ) )
+        WorldRenderer.drawShape( shape, pos.getX() - x, pos.getY() - y, pos.getZ() - z, 0.0F, 0.0F, 0.0F, 0.4F );
-        {
-            RenderGlobal.drawSelectionBoundingBox( CableBounds.getModemBounds( state ), 0, 0, 0, 0.4f );
-        }
-        else
-        {
-            int flags = 0;
-
-            Tessellator tessellator = Tessellator.getInstance();
-            BufferBuilder buffer = tessellator.getBuffer();
-
-            for( EnumFacing facing : EnumFacing.VALUES )
-            {
-                if( BlockCable.doesConnectVisually( state, world, pos, facing ) )
-                {
-                    flags |= 1 << facing.ordinal();
-
-
-                    switch( facing.getAxis() )
-                    {
-                        case X:
-                        {
-                            double offset = facing == EnumFacing.WEST ? -EXPAND : 1 + EXPAND;
-                            double centre = facing == EnumFacing.WEST ? MIN : MAX;
-
-                            buffer.begin( GL11.GL_LINE_STRIP, DefaultVertexFormats.POSITION );
-                            buffer.pos( offset, MIN, MIN ).endVertex();
-                            buffer.pos( offset, MAX, MIN ).endVertex();
-                            buffer.pos( offset, MAX, MAX ).endVertex();
-                            buffer.pos( offset, MIN, MAX ).endVertex();
-                            buffer.pos( offset, MIN, MIN ).endVertex();
-                            tessellator.draw();
-
-                            buffer.begin( GL11.GL_LINES, DefaultVertexFormats.POSITION );
-                            buffer.pos( offset, MIN, MIN ).endVertex();
-                            buffer.pos( centre, MIN, MIN ).endVertex();
-                            buffer.pos( offset, MAX, MIN ).endVertex();
-                            buffer.pos( centre, MAX, MIN ).endVertex();
-                            buffer.pos( offset, MAX, MAX ).endVertex();
-                            buffer.pos( centre, MAX, MAX ).endVertex();
-                            buffer.pos( offset, MIN, MAX ).endVertex();
-                            buffer.pos( centre, MIN, MAX ).endVertex();
-                            tessellator.draw();
-                            break;
-                        }
-                        case Y:
-                        {
-                            double offset = facing == EnumFacing.DOWN ? -EXPAND : 1 + EXPAND;
-                            double centre = facing == EnumFacing.DOWN ? MIN : MAX;
-
-                            buffer.begin( GL11.GL_LINE_STRIP, DefaultVertexFormats.POSITION );
-                            buffer.pos( MIN, offset, MIN ).endVertex();
-                            buffer.pos( MAX, offset, MIN ).endVertex();
-                            buffer.pos( MAX, offset, MAX ).endVertex();
-                            buffer.pos( MIN, offset, MAX ).endVertex();
-                            buffer.pos( MIN, offset, MIN ).endVertex();
-                            tessellator.draw();
-
-                            buffer.begin( GL11.GL_LINES, DefaultVertexFormats.POSITION );
-                            buffer.pos( MIN, offset, MIN ).endVertex();
-                            buffer.pos( MIN, centre, MIN ).endVertex();
-                            buffer.pos( MAX, offset, MIN ).endVertex();
-                            buffer.pos( MAX, centre, MIN ).endVertex();
-                            buffer.pos( MAX, offset, MAX ).endVertex();
-                            buffer.pos( MAX, centre, MAX ).endVertex();
-                            buffer.pos( MIN, offset, MAX ).endVertex();
-                            buffer.pos( MIN, centre, MAX ).endVertex();
-                            tessellator.draw();
-                            break;
-                        }
-                        case Z:
-                        {
-                            double offset = facing == EnumFacing.NORTH ? -EXPAND : 1 + EXPAND;
-                            double centre = facing == EnumFacing.NORTH ? MIN : MAX;
-
-                            buffer.begin( GL11.GL_LINE_STRIP, DefaultVertexFormats.POSITION );
-                            buffer.pos( MIN, MIN, offset ).endVertex();
-                            buffer.pos( MAX, MIN, offset ).endVertex();
-                            buffer.pos( MAX, MAX, offset ).endVertex();
-                            buffer.pos( MIN, MAX, offset ).endVertex();
-                            buffer.pos( MIN, MIN, offset ).endVertex();
-                            tessellator.draw();
-
-                            buffer.begin( GL11.GL_LINES, DefaultVertexFormats.POSITION );
-                            buffer.pos( MIN, MIN, offset ).endVertex();
-                            buffer.pos( MIN, MIN, centre ).endVertex();
-                            buffer.pos( MAX, MIN, offset ).endVertex();
-                            buffer.pos( MAX, MIN, centre ).endVertex();
-                            buffer.pos( MAX, MAX, offset ).endVertex();
-                            buffer.pos( MAX, MAX, centre ).endVertex();
-                            buffer.pos( MIN, MAX, offset ).endVertex();
-                            buffer.pos( MIN, MAX, centre ).endVertex();
-                            tessellator.draw();
-                            break;
-                        }
-                    }
-                }
-            }
-
-            buffer.begin( GL11.GL_LINES, DefaultVertexFormats.POSITION );
-
-            draw( buffer, flags, EnumFacing.WEST, EnumFacing.DOWN, EnumFacing.Axis.Z );
-            draw( buffer, flags, EnumFacing.WEST, EnumFacing.UP, EnumFacing.Axis.Z );
-            draw( buffer, flags, EnumFacing.EAST, EnumFacing.DOWN, EnumFacing.Axis.Z );
-            draw( buffer, flags, EnumFacing.EAST, EnumFacing.UP, EnumFacing.Axis.Z );
-
-            draw( buffer, flags, EnumFacing.WEST, EnumFacing.NORTH, EnumFacing.Axis.Y );
-            draw( buffer, flags, EnumFacing.WEST, EnumFacing.SOUTH, EnumFacing.Axis.Y );
-            draw( buffer, flags, EnumFacing.EAST, EnumFacing.NORTH, EnumFacing.Axis.Y );
-            draw( buffer, flags, EnumFacing.EAST, EnumFacing.SOUTH, EnumFacing.Axis.Y );
-
-            draw( buffer, flags, EnumFacing.DOWN, EnumFacing.NORTH, EnumFacing.Axis.X );
-            draw( buffer, flags, EnumFacing.DOWN, EnumFacing.SOUTH, EnumFacing.Axis.X );
-            draw( buffer, flags, EnumFacing.UP, EnumFacing.NORTH, EnumFacing.Axis.X );
-            draw( buffer, flags, EnumFacing.UP, EnumFacing.SOUTH, EnumFacing.Axis.X );
-
-            tessellator.draw();
-        }
 
         GlStateManager.popMatrix();
+        GlStateManager.matrixMode( GL11.GL_MODELVIEW );
         GlStateManager.depthMask( true );
         GlStateManager.enableTexture2D();
         GlStateManager.disableBlend();
     }
-
-    private static void draw( BufferBuilder buffer, int flags, EnumFacing a, EnumFacing b, EnumFacing.Axis other )
-    {
-        if( ((flags >> a.ordinal()) & 1) != ((flags >> b.ordinal()) & 1) ) return;
-
-        double offA = a.getAxisDirection() == EnumFacing.AxisDirection.NEGATIVE ? MIN : MAX;
-        double offB = b.getAxisDirection() == EnumFacing.AxisDirection.NEGATIVE ? MIN : MAX;
-        switch( other )
-        {
-            case X:
-                buffer.pos( MIN, offA, offB ).endVertex();
-                buffer.pos( MAX, offA, offB ).endVertex();
-                break;
-            case Y:
-                buffer.pos( offA, MIN, offB ).endVertex();
-                buffer.pos( offA, MAX, offB ).endVertex();
-                break;
-            case Z:
-                buffer.pos( offA, offB, MIN ).endVertex();
-                buffer.pos( offA, offB, MAX ).endVertex();
-                break;
-        }
-    }
 }

src/main/java/dan200/computercraft/client/render/TileEntityCableRenderer.java

@@ -7,10 +7,9 @@
 package dan200.computercraft.client.render;
 
 import dan200.computercraft.ComputerCraft;
-import dan200.computercraft.shared.peripheral.PeripheralType;
 import dan200.computercraft.shared.peripheral.modem.wired.BlockCable;
-import dan200.computercraft.shared.peripheral.modem.wired.BlockCableModemVariant;
+import dan200.computercraft.shared.peripheral.modem.wired.CableModemVariant;
-import dan200.computercraft.shared.peripheral.modem.wired.CableBounds;
+import dan200.computercraft.shared.peripheral.modem.wired.CableShapes;
 import dan200.computercraft.shared.peripheral.modem.wired.TileCable;
 import dan200.computercraft.shared.util.WorldUtil;
 import net.minecraft.block.Block;
@@ -18,11 +17,11 @@ import net.minecraft.block.state.IBlockState;
 import net.minecraft.client.Minecraft;
 import net.minecraft.client.renderer.BufferBuilder;
 import net.minecraft.client.renderer.GlStateManager;
-import net.minecraft.client.renderer.RenderGlobal;
 import net.minecraft.client.renderer.Tessellator;
-import net.minecraft.client.renderer.block.model.IBakedModel;
+import net.minecraft.client.renderer.WorldRenderer;
+import net.minecraft.client.renderer.model.IBakedModel;
 import net.minecraft.client.renderer.texture.TextureAtlasSprite;
-import net.minecraft.client.renderer.tileentity.TileEntitySpecialRenderer;
+import net.minecraft.client.renderer.tileentity.TileEntityRenderer;
 import net.minecraft.client.renderer.vertex.DefaultVertexFormats;
 import net.minecraft.util.BlockRenderLayer;
 import net.minecraft.util.math.BlockPos;
@@ -33,20 +32,23 @@ import net.minecraftforge.client.MinecraftForgeClient;
 import org.lwjgl.opengl.GL11;
 
 import javax.annotation.Nonnull;
+import java.util.Random;
 
 /**
  * Render breaking animation only over part of a {@link TileCable}.
  */
-public class TileEntityCableRenderer extends TileEntitySpecialRenderer<TileCable>
+public class TileEntityCableRenderer extends TileEntityRenderer<TileCable>
 {
+    private static final Random random = new Random();
+
     @Override
-    public void render( @Nonnull TileCable te, double x, double y, double z, float partialTicks, int destroyStage, float alpha )
+    public void render( @Nonnull TileCable te, double x, double y, double z, float partialTicks, int destroyStage )
     {
         if( destroyStage < 0 ) return;
 
         BlockPos pos = te.getPos();
 
-        Minecraft mc = Minecraft.getMinecraft();
+        Minecraft mc = Minecraft.getInstance();
 
         RayTraceResult hit = mc.objectMouseOver;
         if( hit == null || !hit.getBlockPos().equals( pos ) ) return;
@@ -58,18 +60,11 @@ public class TileEntityCableRenderer extends TileEntitySpecialRenderer<TileCable
         Block block = state.getBlock();
         if( block != ComputerCraft.Blocks.cable ) return;
 
-        state = state.getActualState( world, pos );
+        state = WorldUtil.isVecInside( CableShapes.getModemShape( state ), hit.hitVec.subtract( pos.getX(), pos.getY(), pos.getZ() ) )
-        if( te.getPeripheralType() != PeripheralType.Cable && WorldUtil.isVecInsideInclusive( CableBounds.getModemBounds( state ), hit.hitVec.subtract( pos.getX(), pos.getY(), pos.getZ() ) ) )
+            ? block.getDefaultState().with( BlockCable.MODEM, state.get( BlockCable.MODEM ) )
-        {
+            : state.with( BlockCable.MODEM, CableModemVariant.None );
-            state = block.getDefaultState().withProperty( BlockCable.Properties.MODEM, state.getValue( BlockCable.Properties.MODEM ) );
-        }
-        else
-        {
-            state = state.withProperty( BlockCable.Properties.MODEM, BlockCableModemVariant.None );
-        }
 
         IBakedModel model = mc.getBlockRendererDispatcher().getModelForState( state );
-        if( model == null ) return;
 
         preRenderDamagedBlocks();
 
@@ -81,11 +76,11 @@ public class TileEntityCableRenderer extends TileEntitySpecialRenderer<TileCable
         ForgeHooksClient.setRenderLayer( block.getRenderLayer() );
 
         // See BlockRendererDispatcher#renderBlockDamage
-        TextureAtlasSprite breakingTexture = mc.getTextureMapBlocks().getAtlasSprite( "minecraft:blocks/destroy_stage_" + destroyStage );
+        TextureAtlasSprite breakingTexture = mc.getTextureMap().getSprite( DESTROY_STAGES[destroyStage] );
-        Minecraft.getMinecraft().getBlockRendererDispatcher().getBlockModelRenderer().renderModel(
+        mc.getBlockRendererDispatcher().getBlockModelRenderer().renderModel(
             world,
             ForgeHooksClient.getDamageModel( model, breakingTexture, state, world, pos ),
-            state, pos, buffer, true
+            state, pos, buffer, true, random, state.getPositionRandom( pos )
         );
 
         ForgeHooksClient.setRenderLayer( BlockRenderLayer.SOLID );
@@ -97,30 +92,30 @@ public class TileEntityCableRenderer extends TileEntitySpecialRenderer<TileCable
     }
 
     /**
-     * @see RenderGlobal#preRenderDamagedBlocks()
+     * @see WorldRenderer#preRenderDamagedBlocks()
      */
     private void preRenderDamagedBlocks()
     {
         GlStateManager.disableLighting();
 
         GlStateManager.enableBlend();
-        GlStateManager.tryBlendFuncSeparate( GlStateManager.SourceFactor.DST_COLOR, GlStateManager.DestFactor.SRC_COLOR, GlStateManager.SourceFactor.ONE, GlStateManager.DestFactor.ZERO );
+        GlStateManager.blendFuncSeparate( GlStateManager.SourceFactor.DST_COLOR, GlStateManager.DestFactor.SRC_COLOR, GlStateManager.SourceFactor.ONE, GlStateManager.DestFactor.ZERO );
         GlStateManager.enableBlend();
-        GlStateManager.color( 1.0F, 1.0F, 1.0F, 0.5F );
+        GlStateManager.color4f( 1.0F, 1.0F, 1.0F, 0.5F );
-        GlStateManager.doPolygonOffset( -3.0F, -3.0F );
+        GlStateManager.polygonOffset( -3.0F, -3.0F );
         GlStateManager.enablePolygonOffset();
         GlStateManager.alphaFunc( 516, 0.1F );
-        GlStateManager.enableAlpha();
+        GlStateManager.enableAlphaTest();
         GlStateManager.pushMatrix();
     }
 
     /**
-     * @see RenderGlobal#postRenderDamagedBlocks()
+     * @see WorldRenderer#postRenderDamagedBlocks()
      */
     private void postRenderDamagedBlocks()
     {
-        GlStateManager.disableAlpha();
+        GlStateManager.disableAlphaTest();
-        GlStateManager.doPolygonOffset( 0.0F, 0.0F );
+        GlStateManager.polygonOffset( 0.0F, 0.0F );
         GlStateManager.disablePolygonOffset();
         GlStateManager.disablePolygonOffset();
         GlStateManager.depthMask( true );

src/main/java/dan200/computercraft/client/render/TileEntityMonitorRenderer.java

@@ -20,16 +20,16 @@ import net.minecraft.client.renderer.BufferBuilder;
 import net.minecraft.client.renderer.GlStateManager;
 import net.minecraft.client.renderer.OpenGlHelper;
 import net.minecraft.client.renderer.Tessellator;
-import net.minecraft.client.renderer.tileentity.TileEntitySpecialRenderer;
+import net.minecraft.client.renderer.tileentity.TileEntityRenderer;
 import net.minecraft.client.renderer.vertex.DefaultVertexFormats;
 import net.minecraft.util.EnumFacing;
 import net.minecraft.util.math.BlockPos;
 import org.lwjgl.opengl.GL11;
 
-public class TileEntityMonitorRenderer extends TileEntitySpecialRenderer<TileMonitor>
+public class TileEntityMonitorRenderer extends TileEntityRenderer<TileMonitor>
 {
     @Override
-    public void render( TileMonitor tileEntity, double posX, double posY, double posZ, float f, int i, float f2 )
+    public void render( TileMonitor tileEntity, double posX, double posY, double posZ, float f, int i )
     {
         if( tileEntity != null )
         {
@@ -37,7 +37,7 @@ public class TileEntityMonitorRenderer extends TileEntitySpecialRenderer<TileMon
         }
     }
 
-    private void renderMonitorAt( TileMonitor monitor, double posX, double posY, double posZ, float f, int i )
+    private static void renderMonitorAt( TileMonitor monitor, double posX, double posY, double posZ, float f, int i )
     {
         // Render from the origin monitor
         ClientMonitor originTerminal = monitor.getClientMonitor();
@@ -73,19 +73,19 @@ public class TileEntityMonitorRenderer extends TileEntitySpecialRenderer<TileMon
         try
         {
             // Setup initial transform
-            GlStateManager.translate( posX + 0.5, posY + 0.5, posZ + 0.5 );
+            GlStateManager.translated( posX + 0.5, posY + 0.5, posZ + 0.5 );
-            GlStateManager.rotate( -yaw, 0.0f, 1.0f, 0.0f );
+            GlStateManager.rotatef( -yaw, 0.0f, 1.0f, 0.0f );
-            GlStateManager.rotate( pitch, 1.0f, 0.0f, 0.0f );
+            GlStateManager.rotatef( pitch, 1.0f, 0.0f, 0.0f );
-            GlStateManager.translate(
+            GlStateManager.translated(
                 -0.5 + TileMonitor.RENDER_BORDER + TileMonitor.RENDER_MARGIN,
-                (origin.getHeight() - 0.5) - (TileMonitor.RENDER_BORDER + TileMonitor.RENDER_MARGIN),
+                origin.getHeight() - 0.5 - (TileMonitor.RENDER_BORDER + TileMonitor.RENDER_MARGIN) + 0,
                 0.5
             );
             double xSize = origin.getWidth() - 2.0 * (TileMonitor.RENDER_MARGIN + TileMonitor.RENDER_BORDER);
             double ySize = origin.getHeight() - 2.0 * (TileMonitor.RENDER_MARGIN + TileMonitor.RENDER_BORDER);
 
             // Get renderers
-            Minecraft mc = Minecraft.getMinecraft();
+            Minecraft mc = Minecraft.getInstance();
             Tessellator tessellator = Tessellator.getInstance();
             BufferBuilder renderer = tessellator.getBuffer();
 
@@ -94,9 +94,9 @@ public class TileEntityMonitorRenderer extends TileEntitySpecialRenderer<TileMon
 
             // Draw the contents
             GlStateManager.depthMask( false );
-            OpenGlHelper.setLightmapTextureCoords( OpenGlHelper.lightmapTexUnit, 0xFF, 0xFF );
+            OpenGlHelper.glMultiTexCoord2f( OpenGlHelper.GL_TEXTURE1, 0xFFFF, 0xFFFF );
             GlStateManager.disableLighting();
-            mc.entityRenderer.disableLightmap();
+            mc.gameRenderer.disableLightmap();
             try
             {
                 Terminal terminal = originTerminal.getTerminal();
@@ -124,14 +124,14 @@ public class TileEntityMonitorRenderer extends TileEntitySpecialRenderer<TileMon
                     {
                         double xScale = xSize / (width * FixedWidthFontRenderer.FONT_WIDTH);
                         double yScale = ySize / (height * FixedWidthFontRenderer.FONT_HEIGHT);
-                        GlStateManager.scale( xScale, -yScale, 1.0 );
+                        GlStateManager.scaled( xScale, -yScale, 1.0 );
 
                         // Draw background
                         mc.getTextureManager().bindTexture( FixedWidthFontRenderer.BACKGROUND );
                         if( redraw )
                         {
                             // Build background display list
-                            GlStateManager.glNewList( originTerminal.renderDisplayLists[0], GL11.GL_COMPILE );
+                            GlStateManager.newList( originTerminal.renderDisplayLists[0], GL11.GL_COMPILE );
                             try
                             {
                                 double marginXSize = TileMonitor.RENDER_MARGIN / xScale;
@@ -142,10 +142,10 @@ public class TileEntityMonitorRenderer extends TileEntitySpecialRenderer<TileMon
                                 GlStateManager.pushMatrix();
                                 try
                                 {
-                                    GlStateManager.scale( 1.0, marginSquash, 1.0 );
+                                    GlStateManager.scaled( 1.0, marginSquash, 1.0 );
-                                    GlStateManager.translate( 0.0, -marginYSize / marginSquash, 0.0 );
+                                    GlStateManager.translated( 0.0, -marginYSize / marginSquash, 0.0 );
                                     fontRenderer.drawStringBackgroundPart( 0, 0, terminal.getBackgroundColourLine( 0 ), marginXSize, marginXSize, greyscale, palette );
-                                    GlStateManager.translate( 0.0, (marginYSize + height * FixedWidthFontRenderer.FONT_HEIGHT) / marginSquash, 0.0 );
+                                    GlStateManager.translated( 0.0, (marginYSize + height * FixedWidthFontRenderer.FONT_HEIGHT) / marginSquash, 0.0 );
                                     fontRenderer.drawStringBackgroundPart( 0, 0, terminal.getBackgroundColourLine( height - 1 ), marginXSize, marginXSize, greyscale, palette );
                                 }
                                 finally
@@ -167,7 +167,7 @@ public class TileEntityMonitorRenderer extends TileEntitySpecialRenderer<TileMon
                             }
                             finally
                             {
-                                GlStateManager.glEndList();
+                                GlStateManager.endList();
                             }
                         }
                         GlStateManager.callList( originTerminal.renderDisplayLists[0] );
@@ -178,7 +178,7 @@ public class TileEntityMonitorRenderer extends TileEntitySpecialRenderer<TileMon
                         if( redraw )
                         {
                             // Build text display list
-                            GlStateManager.glNewList( originTerminal.renderDisplayLists[1], GL11.GL_COMPILE );
+                            GlStateManager.newList( originTerminal.renderDisplayLists[1], GL11.GL_COMPILE );
                             try
                             {
                                 // Lines
@@ -195,7 +195,7 @@ public class TileEntityMonitorRenderer extends TileEntitySpecialRenderer<TileMon
                             }
                             finally
                             {
-                                GlStateManager.glEndList();
+                                GlStateManager.endList();
                             }
                         }
                         GlStateManager.callList( originTerminal.renderDisplayLists[1] );
@@ -206,7 +206,7 @@ public class TileEntityMonitorRenderer extends TileEntitySpecialRenderer<TileMon
                         if( redraw )
                         {
                             // Build cursor display list
-                            GlStateManager.glNewList( originTerminal.renderDisplayLists[2], GL11.GL_COMPILE );
+                            GlStateManager.newList( originTerminal.renderDisplayLists[2], GL11.GL_COMPILE );
                             try
                             {
                                 // Cursor
@@ -227,7 +227,7 @@ public class TileEntityMonitorRenderer extends TileEntitySpecialRenderer<TileMon
                             }
                             finally
                             {
-                                GlStateManager.glEndList();
+                                GlStateManager.endList();
                             }
                         }
                         if( FrameInfo.getGlobalCursorBlink() )
@@ -262,7 +262,7 @@ public class TileEntityMonitorRenderer extends TileEntitySpecialRenderer<TileMon
             finally
             {
                 GlStateManager.depthMask( true );
-                mc.entityRenderer.enableLightmap();
+                mc.gameRenderer.enableLightmap();
                 GlStateManager.enableLighting();
             }
 
@@ -285,7 +285,7 @@ public class TileEntityMonitorRenderer extends TileEntitySpecialRenderer<TileMon
         }
         finally
         {
-            GlStateManager.color( 1.0f, 1.0f, 1.0f, 1.0f );
+            GlStateManager.color4f( 1.0f, 1.0f, 1.0f, 1.0f );
             GlStateManager.popMatrix();
         }
     }

src/main/java/dan200/computercraft/client/render/TileEntityTurtleRenderer.java

@@ -10,20 +10,21 @@ import dan200.computercraft.api.turtle.ITurtleUpgrade;
 import dan200.computercraft.api.turtle.TurtleSide;
 import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.turtle.blocks.TileTurtle;
+import dan200.computercraft.shared.util.DirectionUtil;
 import dan200.computercraft.shared.util.Holiday;
 import dan200.computercraft.shared.util.HolidayUtil;
 import net.minecraft.block.state.IBlockState;
 import net.minecraft.client.Minecraft;
 import net.minecraft.client.renderer.BufferBuilder;
-import net.minecraft.client.renderer.EntityRenderer;
+import net.minecraft.client.renderer.GameRenderer;
 import net.minecraft.client.renderer.GlStateManager;
 import net.minecraft.client.renderer.Tessellator;
-import net.minecraft.client.renderer.block.model.BakedQuad;
+import net.minecraft.client.renderer.model.BakedQuad;
-import net.minecraft.client.renderer.block.model.IBakedModel;
+import net.minecraft.client.renderer.model.IBakedModel;
-import net.minecraft.client.renderer.block.model.ModelManager;
+import net.minecraft.client.renderer.model.ModelManager;
-import net.minecraft.client.renderer.block.model.ModelResourceLocation;
+import net.minecraft.client.renderer.model.ModelResourceLocation;
 import net.minecraft.client.renderer.texture.TextureMap;
-import net.minecraft.client.renderer.tileentity.TileEntitySpecialRenderer;
+import net.minecraft.client.renderer.tileentity.TileEntityRenderer;
 import net.minecraft.client.renderer.vertex.DefaultVertexFormats;
 import net.minecraft.client.renderer.vertex.VertexFormat;
 import net.minecraft.util.EnumFacing;
@@ -36,18 +37,19 @@ import org.lwjgl.opengl.GL11;
 
 import javax.vecmath.Matrix4f;
 import java.util.List;
+import java.util.Random;
 
-public class TileEntityTurtleRenderer extends TileEntitySpecialRenderer<TileTurtle>
+public class TileEntityTurtleRenderer extends TileEntityRenderer<TileTurtle>
 {
-    private static final ModelResourceLocation NORMAL_TURTLE_MODEL = new ModelResourceLocation( "computercraft:turtle", "inventory" );
+    private static final ModelResourceLocation NORMAL_TURTLE_MODEL = new ModelResourceLocation( "computercraft:turtle_normal", "inventory" );
     private static final ModelResourceLocation ADVANCED_TURTLE_MODEL = new ModelResourceLocation( "computercraft:turtle_advanced", "inventory" );
-    private static final ModelResourceLocation COLOUR_TURTLE_MODEL = new ModelResourceLocation( "computercraft:turtle_white", "inventory" );
+    private static final ModelResourceLocation COLOUR_TURTLE_MODEL = new ModelResourceLocation( "computercraft:turtle_colour", "inventory" );
     private static final ModelResourceLocation ELF_OVERLAY_MODEL = new ModelResourceLocation( "computercraft:turtle_elf_overlay", "inventory" );
 
     @Override
-    public void render( TileTurtle tileEntity, double posX, double posY, double posZ, float f, int i, float f2 )
+    public void render( TileTurtle tileEntity, double posX, double posY, double posZ, float partialTicks, int breaking )
     {
-        if( tileEntity != null ) renderTurtleAt( tileEntity, posX, posY, posZ, f, i );
+        if( tileEntity != null ) renderTurtleAt( tileEntity, posX, posY, posZ, partialTicks );
     }
 
     public static ModelResourceLocation getTurtleModel( ComputerFamily family, boolean coloured )
@@ -78,14 +80,14 @@ public class TileEntityTurtleRenderer extends TileEntitySpecialRenderer<TileTurt
         }
     }
 
-    private void renderTurtleAt( TileTurtle turtle, double posX, double posY, double posZ, float f, int i )
+    private void renderTurtleAt( TileTurtle turtle, double posX, double posY, double posZ, float partialTicks )
     {
         // Render the label
         String label = turtle.createProxy().getLabel();
         if( label != null && rendererDispatcher.cameraHitResult != null && turtle.getPos().equals( rendererDispatcher.cameraHitResult.getBlockPos() ) )
         {
             setLightmapDisabled( true );
-            EntityRenderer.drawNameplate(
+            GameRenderer.drawNameplate(
                 getFontRenderer(), label,
                 (float) posX + 0.5F, (float) posY + 1.2F, (float) posZ + 0.5F, 0,
                 rendererDispatcher.entityYaw, rendererDispatcher.entityPitch, false, false
@@ -93,34 +95,28 @@ public class TileEntityTurtleRenderer extends TileEntitySpecialRenderer<TileTurt
             setLightmapDisabled( false );
         }
 
-        IBlockState state = turtle.getWorld().getBlockState( turtle.getPos() );
         GlStateManager.pushMatrix();
         try
         {
+            IBlockState state = turtle.getBlockState();
             // Setup the transform
-            Vec3d offset;
+            Vec3d offset = turtle.getRenderOffset( partialTicks );
-            float yaw;
+            float yaw = turtle.getRenderYaw( partialTicks );
-            offset = turtle.getRenderOffset( f );
+            GlStateManager.translated( posX + offset.x, posY + offset.y, posZ + offset.z );
-            yaw = turtle.getRenderYaw( f );
-            GlStateManager.translate( posX + offset.x, posY + offset.y, posZ + offset.z );
-
             // Render the turtle
-            GlStateManager.translate( 0.5f, 0.5f, 0.5f );
+            GlStateManager.translatef( 0.5f, 0.5f, 0.5f );
-            GlStateManager.rotate( 180.0f - yaw, 0.0f, 1.0f, 0.0f );
+            GlStateManager.rotatef( 180.0f - yaw, 0.0f, 1.0f, 0.0f );
             if( label != null && (label.equals( "Dinnerbone" ) || label.equals( "Grumm" )) )
             {
                 // Flip the model and swap the cull face as winding order will have changed.
-                GlStateManager.scale( 1.0f, -1.0f, 1.0f );
+                GlStateManager.scalef( 1.0f, -1.0f, 1.0f );
                 GlStateManager.cullFace( GlStateManager.CullFace.FRONT );
             }
-            GlStateManager.translate( -0.5f, -0.5f, -0.5f );
+            GlStateManager.translatef( -0.5f, -0.5f, -0.5f );
             // Render the turtle
-            int colour;
+            int colour = turtle.getColour();
-            ComputerFamily family;
+            ComputerFamily family = turtle.getFamily();
-            ResourceLocation overlay;
+            ResourceLocation overlay = turtle.getOverlay();
-            colour = turtle.getColour();
-            family = turtle.getFamily();
-            overlay = turtle.getOverlay();
 
             renderModel( state, getTurtleModel( family, colour != -1 ), colour == -1 ? null : new int[] { colour } );
 
@@ -146,8 +142,8 @@ public class TileEntityTurtleRenderer extends TileEntitySpecialRenderer<TileTurt
             }
 
             // Render the upgrades
-            renderUpgrade( state, turtle, TurtleSide.Left, f );
+            renderUpgrade( state, turtle, TurtleSide.Left, partialTicks );
-            renderUpgrade( state, turtle, TurtleSide.Right, f );
+            renderUpgrade( state, turtle, TurtleSide.Right, partialTicks );
         }
         finally
         {
@@ -165,9 +161,9 @@ public class TileEntityTurtleRenderer extends TileEntitySpecialRenderer<TileTurt
             try
             {
                 float toolAngle = turtle.getToolRenderAngle( side, f );
-                GlStateManager.translate( 0.0f, 0.5f, 0.5f );
+                GlStateManager.translatef( 0.0f, 0.5f, 0.5f );
-                GlStateManager.rotate( -toolAngle, 1.0f, 0.0f, 0.0f );
+                GlStateManager.rotatef( -toolAngle, 1.0f, 0.0f, 0.0f );
-                GlStateManager.translate( 0.0f, -0.5f, -0.5f );
+                GlStateManager.translatef( 0.0f, -0.5f, -0.5f );
 
                 Pair<IBakedModel, Matrix4f> pair = upgrade.getModel( turtle.getAccess(), side );
                 if( pair != null )
@@ -191,24 +187,24 @@ public class TileEntityTurtleRenderer extends TileEntitySpecialRenderer<TileTurt
 
     private void renderModel( IBlockState state, ModelResourceLocation modelLocation, int[] tints )
     {
-        Minecraft mc = Minecraft.getMinecraft();
+        Minecraft mc = Minecraft.getInstance();
-        ModelManager modelManager = mc.getRenderItem().getItemModelMesher().getModelManager();
+        ModelManager modelManager = mc.getItemRenderer().getItemModelMesher().getModelManager();
         renderModel( state, modelManager.getModel( modelLocation ), tints );
     }
 
     private void renderModel( IBlockState state, IBakedModel model, int[] tints )
     {
-        Minecraft mc = Minecraft.getMinecraft();
+        Random random = new Random( 0 );
         Tessellator tessellator = Tessellator.getInstance();
-        mc.getTextureManager().bindTexture( TextureMap.LOCATION_BLOCKS_TEXTURE );
+        rendererDispatcher.textureManager.bindTexture( TextureMap.LOCATION_BLOCKS_TEXTURE );
-        renderQuads( tessellator, model.getQuads( state, null, 0 ), tints );
+        renderQuads( tessellator, model.getQuads( state, null, random ), tints );
-        for( EnumFacing facing : EnumFacing.VALUES )
+        for( EnumFacing facing : DirectionUtil.FACINGS )
         {
-            renderQuads( tessellator, model.getQuads( state, facing, 0 ), tints );
+            renderQuads( tessellator, model.getQuads( state, facing, random ), tints );
         }
     }
 
-    private void renderQuads( Tessellator tessellator, List<BakedQuad> quads, int[] tints )
+    private static void renderQuads( Tessellator tessellator, List<BakedQuad> quads, int[] tints )
     {
         BufferBuilder buffer = tessellator.getBuffer();
         VertexFormat format = DefaultVertexFormats.ITEM;

src/main/java/dan200/computercraft/client/render/TurtleModelLoader.java

@@ -6,26 +6,29 @@
 
 package dan200.computercraft.client.render;
 
-import com.google.common.collect.ImmutableMap;
 import dan200.computercraft.ComputerCraft;
-import net.minecraft.client.renderer.block.model.IBakedModel;
+import net.minecraft.client.renderer.model.IBakedModel;
+import net.minecraft.client.renderer.model.IUnbakedModel;
 import net.minecraft.client.renderer.texture.TextureAtlasSprite;
 import net.minecraft.client.renderer.vertex.VertexFormat;
-import net.minecraft.client.resources.IResourceManager;
+import net.minecraft.resources.IResourceManager;
 import net.minecraft.util.ResourceLocation;
 import net.minecraftforge.client.model.ICustomModelLoader;
-import net.minecraftforge.client.model.IModel;
-import net.minecraftforge.client.model.ModelLoaderRegistry;
 import net.minecraftforge.common.model.IModelState;
 
 import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Set;
 import java.util.function.Function;
+import java.util.stream.Collectors;
 
-public class TurtleModelLoader implements ICustomModelLoader
+public final class TurtleModelLoader implements ICustomModelLoader
 {
-    private static final ResourceLocation NORMAL_TURTLE_MODEL = new ResourceLocation( ComputerCraft.MOD_ID, "block/turtle" );
+    private static final ResourceLocation NORMAL_TURTLE_MODEL = new ResourceLocation( ComputerCraft.MOD_ID, "block/turtle_normal" );
-    private static final ResourceLocation ADVANCED_TURTLE_MODEL = new ResourceLocation( ComputerCraft.MOD_ID, "block/advanced_turtle" );
+    private static final ResourceLocation ADVANCED_TURTLE_MODEL = new ResourceLocation( ComputerCraft.MOD_ID, "block/turtle_advanced" );
-    private static final ResourceLocation COLOUR_TURTLE_MODEL = new ResourceLocation( ComputerCraft.MOD_ID, "block/turtle_white" );
+    private static final ResourceLocation COLOUR_TURTLE_MODEL = new ResourceLocation( ComputerCraft.MOD_ID, "block/turtle_colour" );
 
     public static final TurtleModelLoader INSTANCE = new TurtleModelLoader();
 
@@ -42,80 +45,57 @@ public class TurtleModelLoader implements ICustomModelLoader
     public boolean accepts( @Nonnull ResourceLocation name )
     {
         return name.getNamespace().equals( ComputerCraft.MOD_ID )
-            && (name.getPath().equals( "turtle" ) || name.getPath().equals( "turtle_advanced" ));
+            && (name.getPath().equals( "item/turtle_normal" ) || name.getPath().equals( "item/turtle_advanced" ));
     }
 
     @Nonnull
     @Override
-    public IModel loadModel( @Nonnull ResourceLocation name ) throws Exception
+    public IUnbakedModel loadModel( @Nonnull ResourceLocation name )
     {
         if( name.getNamespace().equals( ComputerCraft.MOD_ID ) )
         {
-            IModel colourModel = ModelLoaderRegistry.getModel( COLOUR_TURTLE_MODEL );
             switch( name.getPath() )
             {
-                case "turtle":
+                case "item/turtle_normal":
-                    return new TurtleModel( ModelLoaderRegistry.getModel( NORMAL_TURTLE_MODEL ), colourModel );
+                    return new TurtleModel( NORMAL_TURTLE_MODEL );
-                case "turtle_advanced":
+                case "item/turtle_advanced":
-                    return new TurtleModel( ModelLoaderRegistry.getModel( ADVANCED_TURTLE_MODEL ), colourModel );
+                    return new TurtleModel( ADVANCED_TURTLE_MODEL );
             }
         }
 
         throw new IllegalStateException( "Loader does not accept " + name );
     }
 
-    private static class TurtleModel implements IModel
+    private static final class TurtleModel implements IUnbakedModel
     {
-        private final IModel family;
+        private final ResourceLocation family;
-        private final IModel colour;
 
-        private TurtleModel( IModel family, IModel colour )
+        private TurtleModel( ResourceLocation family ) {this.family = family;}
+
+        @Nonnull
+        @Override
+        public Collection<ResourceLocation> getDependencies()
         {
-            this.family = family;
+            return Arrays.asList( family, COLOUR_TURTLE_MODEL );
-            this.colour = colour;
         }
 
         @Nonnull
         @Override
-        public IBakedModel bake( @Nonnull IModelState state, @Nonnull VertexFormat format, @Nonnull Function<ResourceLocation, TextureAtlasSprite> function )
+        public Collection<ResourceLocation> getTextures( @Nonnull Function<ResourceLocation, IUnbakedModel> modelGetter, @Nonnull Set<String> missingTextureErrors )
+        {
+            return getDependencies().stream()
+                .flatMap( x -> modelGetter.apply( x ).getTextures( modelGetter, missingTextureErrors ).stream() )
+                .collect( Collectors.toSet() );
+        }
+
+        @Nullable
+        @Override
+        public IBakedModel bake( @Nonnull Function<ResourceLocation, IUnbakedModel> modelGetter, @Nonnull Function<ResourceLocation, TextureAtlasSprite> spriteGetter, @Nonnull IModelState state, boolean uvlock, @Nonnull VertexFormat format )
         {
             return new TurtleSmartItemModel(
-                family.bake( state, format, function ),
+                modelGetter.apply( family ).bake( modelGetter, spriteGetter, state, uvlock, format ),
-                colour.bake( state, format, function )
+                modelGetter.apply( COLOUR_TURTLE_MODEL ).bake( modelGetter, spriteGetter, state, uvlock, format )
             );
         }
-
-        private TurtleModel copy( IModel family, IModel colour )
-        {
-            return this.family == family && this.colour == colour ? this : new TurtleModel( family, colour );
-        }
-
-        @Nonnull
-        @Override
-        public IModel smoothLighting( boolean value )
-        {
-            return copy( family.smoothLighting( value ), colour.smoothLighting( value ) );
-        }
-
-        @Nonnull
-        @Override
-        public IModel gui3d( boolean value )
-        {
-            return copy( family.gui3d( value ), colour.gui3d( value ) );
-        }
-
-        @Nonnull
-        @Override
-        public IModel uvlock( boolean value )
-        {
-            return copy( family.uvlock( value ), colour.uvlock( value ) );
-        }
-
-        @Nonnull
-        @Override
-        public IModel retexture( ImmutableMap<String, String> textures )
-        {
-            return copy( family.retexture( textures ), colour.retexture( textures ) );
-        }
     }
 }

src/main/java/dan200/computercraft/client/render/TurtleMultiModel.java

@@ -7,19 +7,15 @@
 package dan200.computercraft.client.render;
 
 import net.minecraft.block.state.IBlockState;
-import net.minecraft.client.renderer.block.model.BakedQuad;
+import net.minecraft.client.renderer.model.BakedQuad;
-import net.minecraft.client.renderer.block.model.IBakedModel;
+import net.minecraft.client.renderer.model.IBakedModel;
-import net.minecraft.client.renderer.block.model.ItemCameraTransforms;
+import net.minecraft.client.renderer.model.ItemOverrideList;
-import net.minecraft.client.renderer.block.model.ItemOverrideList;
 import net.minecraft.client.renderer.texture.TextureAtlasSprite;
 import net.minecraft.util.EnumFacing;
 
 import javax.annotation.Nonnull;
 import javax.vecmath.Matrix4f;
-import java.util.ArrayList;
+import java.util.*;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
 
 public class TurtleMultiModel implements IBakedModel
 {
@@ -30,8 +26,8 @@ public class TurtleMultiModel implements IBakedModel
     private final Matrix4f m_leftUpgradeTransform;
     private final IBakedModel m_rightUpgradeModel;
     private final Matrix4f m_rightUpgradeTransform;
-    private List<BakedQuad> m_generalQuads;
+    private List<BakedQuad> m_generalQuads = null;
-    private Map<EnumFacing, List<BakedQuad>> m_faceQuads;
+    private Map<EnumFacing, List<BakedQuad>> m_faceQuads = new EnumMap<>( EnumFacing.class );
 
     public TurtleMultiModel( IBakedModel baseModel, IBakedModel overlayModel, Matrix4f generalTransform, IBakedModel leftUpgradeModel, Matrix4f leftUpgradeTransform, IBakedModel rightUpgradeModel, Matrix4f rightUpgradeTransform )
     {
@@ -43,13 +39,11 @@ public class TurtleMultiModel implements IBakedModel
         m_rightUpgradeModel = rightUpgradeModel;
         m_rightUpgradeTransform = rightUpgradeTransform;
         m_generalTransform = generalTransform;
-        m_generalQuads = null;
-        m_faceQuads = new HashMap<>();
     }
 
     @Nonnull
     @Override
-    public List<BakedQuad> getQuads( IBlockState state, EnumFacing side, long rand )
+    public List<BakedQuad> getQuads( IBlockState state, EnumFacing side, @Nonnull Random rand )
     {
         if( side != null )
         {
@@ -63,7 +57,7 @@ public class TurtleMultiModel implements IBakedModel
         }
     }
 
-    private List<BakedQuad> buildQuads( IBlockState state, EnumFacing side, long rand )
+    private List<BakedQuad> buildQuads( IBlockState state, EnumFacing side, Random rand )
     {
         ArrayList<BakedQuad> quads = new ArrayList<>();
         ModelTransformer.transformQuadsTo( quads, m_baseModel.getQuads( state, side, rand ), m_generalTransform );
@@ -127,7 +121,7 @@ public class TurtleMultiModel implements IBakedModel
     @Nonnull
     @Override
     @Deprecated
-    public ItemCameraTransforms getItemCameraTransforms()
+    public net.minecraft.client.renderer.model.ItemCameraTransforms getItemCameraTransforms()
     {
         return m_baseModel.getItemCameraTransforms();
     }
@@ -136,6 +130,6 @@ public class TurtleMultiModel implements IBakedModel
     @Override
     public ItemOverrideList getOverrides()
     {
-        return ItemOverrideList.NONE;
+        return ItemOverrideList.EMPTY;
     }
 }

src/main/java/dan200/computercraft/client/render/TurtleSmartItemModel.java

@@ -9,12 +9,12 @@ package dan200.computercraft.client.render;
 import com.google.common.base.Objects;
 import dan200.computercraft.api.turtle.ITurtleUpgrade;
 import dan200.computercraft.api.turtle.TurtleSide;
-import dan200.computercraft.shared.turtle.items.ItemTurtleBase;
+import dan200.computercraft.shared.turtle.items.ItemTurtle;
 import dan200.computercraft.shared.util.Holiday;
 import dan200.computercraft.shared.util.HolidayUtil;
 import net.minecraft.block.state.IBlockState;
 import net.minecraft.client.Minecraft;
-import net.minecraft.client.renderer.block.model.*;
+import net.minecraft.client.renderer.model.*;
 import net.minecraft.client.renderer.texture.TextureAtlasSprite;
 import net.minecraft.entity.EntityLivingBase;
 import net.minecraft.item.ItemStack;
@@ -26,9 +26,9 @@ import org.apache.commons.lang3.tuple.Pair;
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 import javax.vecmath.Matrix4f;
-import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
+import java.util.Random;
 
 public class TurtleSmartItemModel implements IBakedModel
 {
@@ -106,13 +106,13 @@ public class TurtleSmartItemModel implements IBakedModel
         this.colourModel = colourModel;
 
         m_cachedModels = new HashMap<>();
-        m_overrides = new ItemOverrideList( new ArrayList<>() )
+        m_overrides = new ItemOverrideList()
         {
             @Nonnull
             @Override
-            public IBakedModel handleItemState( @Nonnull IBakedModel originalModel, @Nonnull ItemStack stack, @Nullable World world, @Nullable EntityLivingBase entity )
+            public IBakedModel getModelWithOverrides( @Nonnull IBakedModel originalModel, @Nonnull ItemStack stack, @Nullable World world, @Nullable EntityLivingBase entity )
             {
-                ItemTurtleBase turtle = (ItemTurtleBase) stack.getItem();
+                ItemTurtle turtle = (ItemTurtle) stack.getItem();
                 int colour = turtle.getColour( stack );
                 ITurtleUpgrade leftUpgrade = turtle.getUpgrade( stack, TurtleSide.Left );
                 ITurtleUpgrade rightUpgrade = turtle.getUpgrade( stack, TurtleSide.Right );
@@ -138,15 +138,15 @@ public class TurtleSmartItemModel implements IBakedModel
 
     private IBakedModel buildModel( TurtleModelCombination combo )
     {
-        Minecraft mc = Minecraft.getMinecraft();
+        Minecraft mc = Minecraft.getInstance();
-        ModelManager modelManager = mc.getRenderItem().getItemModelMesher().getModelManager();
+        ModelManager modelManager = mc.getItemRenderer().getItemModelMesher().getModelManager();
         ModelResourceLocation overlayModelLocation = TileEntityTurtleRenderer.getTurtleOverlayModel( combo.m_overlay, combo.m_christmas );
 
         IBakedModel baseModel = combo.m_colour ? colourModel : familyModel;
-        IBakedModel overlayModel = (overlayModelLocation != null) ? modelManager.getModel( overlayModelLocation ) : null;
+        IBakedModel overlayModel = overlayModelLocation != null ? modelManager.getModel( overlayModelLocation ) : null;
         Matrix4f transform = combo.m_flip ? s_flip : s_identity;
-        Pair<IBakedModel, Matrix4f> leftModel = (combo.m_leftUpgrade != null) ? combo.m_leftUpgrade.getModel( null, TurtleSide.Left ) : null;
+        Pair<IBakedModel, Matrix4f> leftModel = combo.m_leftUpgrade != null ? combo.m_leftUpgrade.getModel( null, TurtleSide.Left ) : null;
-        Pair<IBakedModel, Matrix4f> rightModel = (combo.m_rightUpgrade != null) ? combo.m_rightUpgrade.getModel( null, TurtleSide.Right ) : null;
+        Pair<IBakedModel, Matrix4f> rightModel = combo.m_rightUpgrade != null ? combo.m_rightUpgrade.getModel( null, TurtleSide.Right ) : null;
         if( leftModel != null && rightModel != null )
         {
             return new TurtleMultiModel( baseModel, overlayModel, transform, leftModel.getLeft(), leftModel.getRight(), rightModel.getLeft(), rightModel.getRight() );
@@ -167,7 +167,7 @@ public class TurtleSmartItemModel implements IBakedModel
 
     @Nonnull
     @Override
-    public List<BakedQuad> getQuads( IBlockState state, EnumFacing facing, long rand )
+    public List<BakedQuad> getQuads( IBlockState state, EnumFacing facing, @Nonnull Random rand )
     {
         return familyModel.getQuads( state, facing, rand );
     }

src/main/java/dan200/computercraft/core/apis/AddressPredicate.java

@@ -12,6 +12,7 @@ import dan200.computercraft.ComputerCraft;
 import java.net.Inet6Address;
 import java.net.InetAddress;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.List;
 import java.util.regex.Pattern;
 
@@ -20,7 +21,7 @@ import java.util.regex.Pattern;
  */
 public class AddressPredicate
 {
-    private static class HostRange
+    private static final class HostRange
     {
         private final byte[] min;
         private final byte[] max;
@@ -50,6 +51,11 @@ public class AddressPredicate
     private final List<HostRange> ranges;
 
     public AddressPredicate( String... filters )
+    {
+        this( Arrays.asList( filters ) );
+    }
+
+    public AddressPredicate( Iterable<? extends String> filters )
     {
         List<Pattern> wildcards = this.wildcards = new ArrayList<>();
         List<HostRange> ranges = this.ranges = new ArrayList<>();
@@ -69,7 +75,10 @@ public class AddressPredicate
                 }
                 catch( NumberFormatException e )
                 {
-                    ComputerCraft.log.warn( "Cannot parse CIDR size from {} ({})", filter, prefixSizeStr );
+                    ComputerCraft.log.error(
+                        "Malformed http whitelist/blacklist entry '{}': Cannot extract size of CIDR mask from '{}'.",
+                        filter, prefixSizeStr
+                    );
                     continue;
                 }
 
@@ -80,7 +89,10 @@ public class AddressPredicate
                 }
                 catch( IllegalArgumentException e )
                 {
-                    ComputerCraft.log.warn( "Cannot parse IP address from {} ({})", filter, addressStr );
+                    ComputerCraft.log.error(
+                        "Malformed http whitelist/blacklist entry '{}': Cannot extract IP address from '{}'.",
+                        filter, prefixSizeStr
+                    );
                     continue;
                 }
 

src/main/java/dan200/computercraft/core/apis/ApiFactories.java

@@ -6,13 +6,13 @@
 
 package dan200.computercraft.core.apis;
 
-import com.google.common.base.Preconditions;
 import dan200.computercraft.api.lua.ILuaAPIFactory;
 
 import javax.annotation.Nonnull;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.LinkedHashSet;
+import java.util.Objects;
 
 public final class ApiFactories
 {
@@ -23,9 +23,9 @@ public final class ApiFactories
     private static final Collection<ILuaAPIFactory> factories = new LinkedHashSet<>();
     private static final Collection<ILuaAPIFactory> factoriesView = Collections.unmodifiableCollection( factories );
 
-    public static void register( @Nonnull ILuaAPIFactory factory )
+    public static synchronized void register( @Nonnull ILuaAPIFactory factory )
     {
-        Preconditions.checkNotNull( factory, "provider cannot be null" );
+        Objects.requireNonNull( factory, "provider cannot be null" );
         factories.add( factory );
     }
 

src/main/java/dan200/computercraft/core/apis/ComputerAccess.java

@@ -6,12 +6,10 @@
 
 package dan200.computercraft.core.apis;
 
-import com.google.common.base.Preconditions;
 import dan200.computercraft.api.filesystem.IMount;
 import dan200.computercraft.api.filesystem.IWritableMount;
 import dan200.computercraft.api.peripheral.IComputerAccess;
-import dan200.computercraft.core.computer.Computer;
+import dan200.computercraft.api.peripheral.IWorkMonitor;
-import dan200.computercraft.core.computer.IComputerOwned;
 import dan200.computercraft.core.filesystem.FileSystem;
 import dan200.computercraft.core.filesystem.FileSystemException;
 
@@ -21,22 +19,22 @@ import java.util.HashSet;
 import java.util.Objects;
 import java.util.Set;
 
-public abstract class ComputerAccess implements IComputerAccess, IComputerOwned
+public abstract class ComputerAccess implements IComputerAccess
 {
     private final IAPIEnvironment m_environment;
     private final Set<String> m_mounts = new HashSet<>();
 
-    protected ComputerAccess( IAPIEnvironment m_environment )
+    protected ComputerAccess( IAPIEnvironment environment )
     {
-        this.m_environment = m_environment;
+        this.m_environment = environment;
     }
 
     public void unmountAll()
     {
         FileSystem fileSystem = m_environment.getFileSystem();
-        for( String m_mount : m_mounts )
+        for( String mount : m_mounts )
         {
-            fileSystem.unmount( m_mount );
+            fileSystem.unmount( mount );
         }
         m_mounts.clear();
     }
@@ -122,15 +120,15 @@ public abstract class ComputerAccess implements IComputerAccess, IComputerOwned
     @Override
     public void queueEvent( @Nonnull final String event, final Object[] arguments )
     {
-        Preconditions.checkNotNull( event, "event cannot be null" );
+        Objects.requireNonNull( event, "event cannot be null" );
         m_environment.queueEvent( event, arguments );
     }
 
     @Nullable
     @Override
-    public Computer getComputer()
+    public IWorkMonitor getMainThreadMonitor()
     {
-        return m_environment.getComputer();
+        return m_environment.getMainThreadMonitor();
     }
 
     private String findFreeLocation( String desiredLoc )

src/main/java/dan200/computercraft/core/apis/FSAPI.java

@@ -34,9 +34,9 @@ public class FSAPI implements ILuaAPI
     private IAPIEnvironment m_env;
     private FileSystem m_fileSystem;
 
-    public FSAPI( IAPIEnvironment _env )
+    public FSAPI( IAPIEnvironment env )
     {
-        m_env = _env;
+        m_env = env;
         m_fileSystem = null;
     }
 
@@ -353,10 +353,8 @@ public class FSAPI implements ILuaAPI
                 return new Object[] { FileSystem.getDirectory( path ) };
             }
             default:
-            {
+                assert false;
-                assert (false);
                 return null;
-            }
         }
     }
 }

src/main/java/dan200/computercraft/core/apis/HTTPAPI.java

@@ -199,9 +199,7 @@ public class HTTPAPI implements ILuaAPI
                 }
             }
             default:
-            {
                 return null;
-            }
         }
     }
 
@@ -209,14 +207,14 @@ public class HTTPAPI implements ILuaAPI
     private static HttpHeaders getHeaders( @Nonnull Map<?, ?> headerTable ) throws LuaException
     {
         HttpHeaders headers = new DefaultHttpHeaders();
-        for( Object key : headerTable.keySet() )
+        for( Map.Entry<?, ?> entry : headerTable.entrySet() )
         {
-            Object value = headerTable.get( key );
+            Object value = entry.getValue();
-            if( key instanceof String && value instanceof String )
+            if( entry.getKey() instanceof String && value instanceof String )
             {
                 try
                 {
-                    headers.add( (String) key, value );
+                    headers.add( (String) entry.getKey(), value );
                 }
                 catch( IllegalArgumentException e )
                 {

src/main/java/dan200/computercraft/core/apis/IAPIEnvironment.java

@@ -7,9 +7,9 @@
 package dan200.computercraft.core.apis;
 
 import dan200.computercraft.api.peripheral.IPeripheral;
-import dan200.computercraft.core.computer.Computer;
+import dan200.computercraft.api.peripheral.IWorkMonitor;
+import dan200.computercraft.core.computer.ComputerSide;
 import dan200.computercraft.core.computer.IComputerEnvironment;
-import dan200.computercraft.core.computer.IComputerOwned;
 import dan200.computercraft.core.filesystem.FileSystem;
 import dan200.computercraft.core.terminal.Terminal;
 import dan200.computercraft.core.tracking.TrackingField;
@@ -17,28 +17,22 @@ import dan200.computercraft.core.tracking.TrackingField;
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 
-public interface IAPIEnvironment extends IComputerOwned
+public interface IAPIEnvironment
 {
-    String[] SIDE_NAMES = new String[] {
+    @FunctionalInterface
-        "bottom", "top", "back", "front", "right", "left",
-    };
-
-    int SIDE_COUNT = 6;
-
     interface IPeripheralChangeListener
     {
-        void onPeripheralChanged( int side, @Nullable IPeripheral newPeripheral );
+        void onPeripheralChanged( ComputerSide side, @Nullable IPeripheral newPeripheral );
     }
 
-    @Nonnull
-    @Override
-    Computer getComputer();
-
     int getComputerID();
 
     @Nonnull
     IComputerEnvironment getComputerEnvironment();
 
+    @Nonnull
+    IWorkMonitor getMainThreadMonitor();
+
     @Nonnull
     Terminal getTerminal();
 
@@ -50,22 +44,22 @@ public interface IAPIEnvironment extends IComputerOwned
 
     void queueEvent( String event, Object[] args );
 
-    void setOutput( int side, int output );
+    void setOutput( ComputerSide side, int output );
 
-    int getOutput( int side );
+    int getOutput( ComputerSide side );
 
-    int getInput( int side );
+    int getInput( ComputerSide side );
 
-    void setBundledOutput( int side, int output );
+    void setBundledOutput( ComputerSide side, int output );
 
-    int getBundledOutput( int side );
+    int getBundledOutput( ComputerSide side );
 
-    int getBundledInput( int side );
+    int getBundledInput( ComputerSide side );
 
     void setPeripheralChangeListener( @Nullable IPeripheralChangeListener listener );
 
     @Nullable
-    IPeripheral getPeripheral( int side );
+    IPeripheral getPeripheral( ComputerSide side );
 
     String getLabel();
 

src/main/java/dan200/computercraft/core/apis/OSAPI.java

@@ -39,7 +39,7 @@ public class OSAPI implements ILuaAPI
         }
     }
 
-    private class Alarm implements Comparable<Alarm>
+    private static class Alarm implements Comparable<Alarm>
     {
         public final double m_time;
         public final int m_day;
@@ -110,7 +110,7 @@ public class OSAPI implements ILuaAPI
             {
                 Map.Entry<Integer, Timer> entry = it.next();
                 Timer timer = entry.getValue();
-                timer.m_ticksLeft = timer.m_ticksLeft - 1;
+                timer.m_ticksLeft--;
                 if( timer.m_ticksLeft <= 0 )
                 {
                     // Queue the "timer" event
@@ -198,7 +198,7 @@ public class OSAPI implements ILuaAPI
 
     private int getDayForCalendar( Calendar c )
     {
-        GregorianCalendar g = (c instanceof GregorianCalendar) ? (GregorianCalendar) c : new GregorianCalendar();
+        GregorianCalendar g = c instanceof GregorianCalendar ? (GregorianCalendar) c : new GregorianCalendar();
         int year = c.get( Calendar.YEAR );
         int day = 0;
         for( int y = 1970; y < year; y++ )
@@ -219,12 +219,9 @@ public class OSAPI implements ILuaAPI
     {
         switch( method )
         {
-            case 0:
+            case 0: // queueEvent
-            {
-                // queueEvent
                 queueLuaEvent( getString( args, 0 ), trimArray( args, 1 ) );
                 return null;
-            }
             case 1:
             {
                 // startTimer
@@ -245,29 +242,20 @@ public class OSAPI implements ILuaAPI
                 }
                 synchronized( m_alarms )
                 {
-                    int day = (time > m_time) ? m_day : (m_day + 1);
+                    int day = time > m_time ? m_day : m_day + 1;
                     m_alarms.put( m_nextAlarmToken, new Alarm( time, day ) );
                     return new Object[] { m_nextAlarmToken++ };
                 }
             }
-            case 3:
+            case 3: // shutdown
-            {
-                // shutdown
                 m_apiEnvironment.shutdown();
                 return null;
-            }
+            case 4: // reboot
-            case 4:
-            {
-                // reboot
                 m_apiEnvironment.reboot();
                 return null;
-            }
             case 5:
-            case 6:
+            case 6: // computerID/getComputerID
-            {
-                // computerID/getComputerID
                 return new Object[] { getComputerID() };
-            }
             case 7:
             {
                 // setComputerLabel
@@ -286,19 +274,16 @@ public class OSAPI implements ILuaAPI
                 }
                 return null;
             }
-            case 10:
+            case 10: // clock
-            {
-                // clock
                 synchronized( m_timers )
                 {
                     return new Object[] { m_clock * 0.05 };
                 }
-            }
             case 11:
             {
                 // time
                 String param = optString( args, 0, "ingame" );
-                switch( param )
+                switch( param.toLowerCase( Locale.ROOT ) )
                 {
                     case "utc":
                     {
@@ -326,7 +311,7 @@ public class OSAPI implements ILuaAPI
             {
                 // day
                 String param = optString( args, 0, "ingame" );
-                switch( param )
+                switch( param.toLowerCase( Locale.ROOT ) )
                 {
                     case "utc":
                     {
@@ -356,10 +341,7 @@ public class OSAPI implements ILuaAPI
                 int token = getInt( args, 0 );
                 synchronized( m_timers )
                 {
-                    if( m_timers.containsKey( token ) )
+                    m_timers.remove( token );
-                    {
-                        m_timers.remove( token );
-                    }
                 }
                 return null;
             }
@@ -369,10 +351,7 @@ public class OSAPI implements ILuaAPI
                 int token = getInt( args, 0 );
                 synchronized( m_alarms )
                 {
-                    if( m_alarms.containsKey( token ) )
+                    m_alarms.remove( token );
-                    {
-                        m_alarms.remove( token );
-                    }
                 }
                 return null;
             }
@@ -380,7 +359,7 @@ public class OSAPI implements ILuaAPI
             {
                 // epoch
                 String param = optString( args, 0, "ingame" );
-                switch( param )
+                switch( param.toLowerCase( Locale.ROOT ) )
                 {
                     case "utc":
                     {
@@ -407,9 +386,7 @@ public class OSAPI implements ILuaAPI
                 }
             }
             default:
-            {
                 return null;
-            }
         }
     }
 

src/main/java/dan200/computercraft/core/apis/PeripheralAPI.java

@@ -12,9 +12,7 @@ import dan200.computercraft.api.lua.ILuaAPI;
 import dan200.computercraft.api.lua.ILuaContext;
 import dan200.computercraft.api.lua.LuaException;
 import dan200.computercraft.api.peripheral.IPeripheral;
-import dan200.computercraft.core.computer.Computer;
+import dan200.computercraft.core.computer.ComputerSide;
-import dan200.computercraft.core.computer.ComputerThread;
-import dan200.computercraft.core.computer.ITask;
 import dan200.computercraft.core.tracking.TrackingField;
 
 import javax.annotation.Nonnull;
@@ -47,8 +45,8 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
 
             m_type = peripheral.getType();
             m_methods = peripheral.getMethodNames();
-            assert (m_type != null);
+            assert m_type != null;
-            assert (m_methods != null);
+            assert m_methods != null;
 
             m_methodMap = new HashMap<>();
             for( int i = 0; i < m_methods.length; i++ )
@@ -231,9 +229,9 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
     private final PeripheralWrapper[] m_peripherals;
     private boolean m_running;
 
-    public PeripheralAPI( IAPIEnvironment _environment )
+    public PeripheralAPI( IAPIEnvironment environment )
     {
-        m_environment = _environment;
+        m_environment = environment;
         m_environment.setPeripheralChangeListener( this );
 
         m_peripherals = new PeripheralWrapper[6];
@@ -248,76 +246,33 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
     // IPeripheralChangeListener
 
     @Override
-    public void onPeripheralChanged( int side, IPeripheral newPeripheral )
+    public void onPeripheralChanged( ComputerSide side, IPeripheral newPeripheral )
     {
         synchronized( m_peripherals )
         {
-            if( m_peripherals[side] != null )
+            int index = side.ordinal();
+            if( m_peripherals[index] != null )
             {
                 // Queue a detachment
-                final PeripheralWrapper wrapper = m_peripherals[side];
+                final PeripheralWrapper wrapper = m_peripherals[index];
-                ComputerThread.queueTask( new ITask()
+                if( wrapper.isAttached() ) wrapper.detach();
-                {
-                    @Override
-                    public Computer getOwner()
-                    {
-                        return m_environment.getComputer();
-                    }
-
-                    @Override
-                    public void execute()
-                    {
-                        synchronized( m_peripherals )
-                        {
-                            if( wrapper.isAttached() )
-                            {
-                                wrapper.detach();
-                            }
-                        }
-                    }
-                }, null );
 
                 // Queue a detachment event
-                m_environment.queueEvent( "peripheral_detach", new Object[] { IAPIEnvironment.SIDE_NAMES[side] } );
+                m_environment.queueEvent( "peripheral_detach", new Object[] { side.getName() } );
             }
 
             // Assign the new peripheral
-            if( newPeripheral != null )
+            m_peripherals[index] = newPeripheral == null ? null
-            {
+                : new PeripheralWrapper( newPeripheral, side.getName() );
-                m_peripherals[side] = new PeripheralWrapper( newPeripheral, IAPIEnvironment.SIDE_NAMES[side] );
-            }
-            else
-            {
-                m_peripherals[side] = null;
-            }
 
-            if( m_peripherals[side] != null )
+            if( m_peripherals[index] != null )
             {
                 // Queue an attachment
-                final PeripheralWrapper wrapper = m_peripherals[side];
+                final PeripheralWrapper wrapper = m_peripherals[index];
-                ComputerThread.queueTask( new ITask()
+                if( m_running && !wrapper.isAttached() ) wrapper.attach();
-                {
-                    @Override
-                    public Computer getOwner()
-                    {
-                        return m_environment.getComputer();
-                    }
-
-                    @Override
-                    public void execute()
-                    {
-                        synchronized( m_peripherals )
-                        {
-                            if( m_running && !wrapper.isAttached() )
-                            {
-                                wrapper.attach();
-                            }
-                        }
-                    }
-                }, null );
 
                 // Queue an attachment event
-                m_environment.queueEvent( "peripheral", new Object[] { IAPIEnvironment.SIDE_NAMES[side] } );
+                m_environment.queueEvent( "peripheral", new Object[] { side.getName() } );
             }
         }
     }
@@ -341,10 +296,7 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
             for( int i = 0; i < 6; i++ )
             {
                 PeripheralWrapper wrapper = m_peripherals[i];
-                if( wrapper != null && !wrapper.isAttached() )
+                if( wrapper != null && !wrapper.isAttached() ) wrapper.attach();
-                {
-                    wrapper.attach();
-                }
             }
         }
     }
@@ -387,16 +339,13 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
             {
                 // isPresent
                 boolean present = false;
-                int side = parseSide( args );
+                ComputerSide side = ComputerSide.valueOfInsensitive( getString( args, 0 ) );
-                if( side >= 0 )
+                if( side != null )
                 {
                     synchronized( m_peripherals )
                     {
-                        PeripheralWrapper p = m_peripherals[side];
+                        PeripheralWrapper p = m_peripherals[side.ordinal()];
-                        if( p != null )
+                        if( p != null ) present = true;
-                        {
-                            present = true;
-                        }
                     }
                 }
                 return new Object[] { present };
@@ -404,21 +353,14 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
             case 1:
             {
                 // getType
-                String type = null;
+                ComputerSide side = ComputerSide.valueOfInsensitive( getString( args, 0 ) );
-                int side = parseSide( args );
+                if( side != null )
-                if( side >= 0 )
                 {
+                    String type = null;
                     synchronized( m_peripherals )
                     {
-                        PeripheralWrapper p = m_peripherals[side];
+                        PeripheralWrapper p = m_peripherals[side.ordinal()];
-                        if( p != null )
+                        if( p != null ) return new Object[] { p.getType() };
-                        {
-                            type = p.getType();
-                        }
-                    }
-                    if( type != null )
-                    {
-                        return new Object[] { type };
                     }
                 }
                 return null;
@@ -427,12 +369,12 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
             {
                 // getMethods
                 String[] methods = null;
-                int side = parseSide( args );
+                ComputerSide side = ComputerSide.valueOfInsensitive( getString( args, 0 ) );
-                if( side >= 0 )
+                if( side != null )
                 {
                     synchronized( m_peripherals )
                     {
-                        PeripheralWrapper p = m_peripherals[side];
+                        PeripheralWrapper p = m_peripherals[side.ordinal()];
                         if( p != null )
                         {
                             methods = p.getMethods();
@@ -453,16 +395,16 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
             case 3:
             {
                 // call
-                int side = parseSide( args );
+                ComputerSide side = ComputerSide.valueOfInsensitive( getString( args, 0 ) );
                 String methodName = getString( args, 1 );
                 Object[] methodArgs = Arrays.copyOfRange( args, 2, args.length );
 
-                if( side >= 0 )
+                if( side != null )
                 {
                     PeripheralWrapper p;
                     synchronized( m_peripherals )
                     {
-                        p = m_peripherals[side];
+                        p = m_peripherals[side.ordinal()];
                     }
                     if( p != null )
                     {
@@ -472,24 +414,7 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
                 throw new LuaException( "No peripheral attached" );
             }
             default:
-            {
                 return null;
-            }
         }
     }
-
-    // Privates
-
-    private int parseSide( Object[] args ) throws LuaException
-    {
-        String side = getString( args, 0 );
-        for( int n = 0; n < IAPIEnvironment.SIDE_NAMES.length; n++ )
-        {
-            if( side.equals( IAPIEnvironment.SIDE_NAMES[n] ) )
-            {
-                return n;
-            }
-        }
-        return -1;
-    }
 }

src/main/java/dan200/computercraft/core/apis/RedstoneAPI.java

@@ -9,6 +9,7 @@ package dan200.computercraft.core.apis;
 import dan200.computercraft.api.lua.ILuaAPI;
 import dan200.computercraft.api.lua.ILuaContext;
 import dan200.computercraft.api.lua.LuaException;
+import dan200.computercraft.core.computer.ComputerSide;
 
 import javax.annotation.Nonnull;
 import java.util.HashMap;
@@ -64,65 +65,49 @@ public class RedstoneAPI implements ILuaAPI
             {
                 // getSides
                 Map<Object, Object> table = new HashMap<>();
-                for( int i = 0; i < IAPIEnvironment.SIDE_NAMES.length; i++ )
+                for( int i = 0; i < ComputerSide.NAMES.length; i++ )
                 {
-                    table.put( i + 1, IAPIEnvironment.SIDE_NAMES[i] );
+                    table.put( i + 1, ComputerSide.NAMES[i] );
                 }
                 return new Object[] { table };
             }
             case 1:
             {
                 // setOutput
-                int side = parseSide( args );
+                ComputerSide side = parseSide( args );
                 boolean output = getBoolean( args, 1 );
                 m_environment.setOutput( side, output ? 15 : 0 );
                 return null;
             }
-            case 2:
+            case 2: // getOutput
-            {
+                return new Object[] { m_environment.getOutput( parseSide( args ) ) > 0 };
-                // getOutput
+            case 3: // getInput
-                int side = parseSide( args );
+                return new Object[] { m_environment.getInput( parseSide( args ) ) > 0 };
-                return new Object[] { m_environment.getOutput( side ) > 0 };
-            }
-            case 3:
-            {
-                // getInput
-                int side = parseSide( args );
-                return new Object[] { m_environment.getInput( side ) > 0 };
-            }
             case 4:
             {
                 // setBundledOutput
-                int side = parseSide( args );
+                ComputerSide side = parseSide( args );
                 int output = getInt( args, 1 );
                 m_environment.setBundledOutput( side, output );
                 return null;
             }
-            case 5:
+            case 5: // getBundledOutput
-            {
+                return new Object[] { m_environment.getBundledOutput( parseSide( args ) ) };
-                // getBundledOutput
+            case 6: // getBundledInput
-                int side = parseSide( args );
+                return new Object[] { m_environment.getBundledInput( parseSide( args ) ) };
-                return new Object[] { m_environment.getBundledOutput( side ) };
-            }
-            case 6:
-            {
-                // getBundledInput
-                int side = parseSide( args );
-                return new Object[] { m_environment.getBundledInput( side ) };
-            }
             case 7:
             {
                 // testBundledInput
-                int side = parseSide( args );
+                ComputerSide side = parseSide( args );
                 int mask = getInt( args, 1 );
                 int input = m_environment.getBundledInput( side );
-                return new Object[] { ((input & mask) == mask) };
+                return new Object[] { (input & mask) == mask };
             }
             case 8:
             case 9:
             {
                 // setAnalogOutput/setAnalogueOutput
-                int side = parseSide( args );
+                ComputerSide side = parseSide( args );
                 int output = getInt( args, 1 );
                 if( output < 0 || output > 15 )
                 {
@@ -132,36 +117,20 @@ public class RedstoneAPI implements ILuaAPI
                 return null;
             }
             case 10:
-            case 11:
+            case 11: // getAnalogOutput/getAnalogueOutput
-            {
+                return new Object[] { m_environment.getOutput( parseSide( args ) ) };
-                // getAnalogOutput/getAnalogueOutput
-                int side = parseSide( args );
-                return new Object[] { m_environment.getOutput( side ) };
-            }
             case 12:
-            case 13:
+            case 13: // getAnalogInput/getAnalogueInput
-            {
+                return new Object[] { m_environment.getInput( parseSide( args ) ) };
-                // getAnalogInput/getAnalogueInput
-                int side = parseSide( args );
-                return new Object[] { m_environment.getInput( side ) };
-            }
             default:
-            {
                 return null;
-            }
         }
     }
 
-    private int parseSide( Object[] args ) throws LuaException
+    private static ComputerSide parseSide( Object[] args ) throws LuaException
     {
-        String side = getString( args, 0 );
+        ComputerSide side = ComputerSide.valueOfInsensitive( getString( args, 0 ) );
-        for( int n = 0; n < IAPIEnvironment.SIDE_NAMES.length; n++ )
+        if( side == null ) throw new LuaException( "Invalid side." );
-        {
+        return side;
-            if( side.equals( IAPIEnvironment.SIDE_NAMES[n] ) )
-            {
-                return n;
-            }
-        }
-        throw new LuaException( "Invalid side." );
     }
 }

src/main/java/dan200/computercraft/core/apis/TermAPI.java

@@ -24,10 +24,10 @@ public class TermAPI implements ILuaAPI
     private final Terminal m_terminal;
     private final IComputerEnvironment m_environment;
 
-    public TermAPI( IAPIEnvironment _environment )
+    public TermAPI( IAPIEnvironment environment )
     {
-        m_terminal = _environment.getTerminal();
+        m_terminal = environment.getTerminal();
-        m_environment = _environment.getComputerEnvironment();
+        m_environment = environment.getComputerEnvironment();
     }
 
     @Override
@@ -111,16 +111,7 @@ public class TermAPI implements ILuaAPI
             case 0:
             {
                 // write
-                String text;
+                String text = args.length > 0 && args[0] != null ? args[0].toString() : "";
-                if( args.length > 0 && args[0] != null )
-                {
-                    text = args[0].toString();
-                }
-                else
-                {
-                    text = "";
-                }
-
                 synchronized( m_terminal )
                 {
                     m_terminal.write( text );
@@ -181,24 +172,18 @@ public class TermAPI implements ILuaAPI
                 }
                 return new Object[] { width, height };
             }
-            case 6:
+            case 6: // clear
-            {
-                // clear
                 synchronized( m_terminal )
                 {
                     m_terminal.clear();
                 }
                 return null;
-            }
+            case 7: // clearLine
-            case 7:
-            {
-                // clearLine
                 synchronized( m_terminal )
                 {
                     m_terminal.clearLine();
                 }
                 return null;
-            }
             case 8:
             case 9:
             {
@@ -222,23 +207,14 @@ public class TermAPI implements ILuaAPI
                 return null;
             }
             case 12:
-            case 13:
+            case 13: // isColour/isColor
-            {
-                // isColour/isColor
                 return new Object[] { m_environment.isColour() };
-            }
             case 14:
-            case 15:
+            case 15: // getTextColour/getTextColor
-            {
-                // getTextColour/getTextColor
                 return encodeColour( m_terminal.getTextColour() );
-            }
             case 16:
-            case 17:
+            case 17: // getBackgroundColour/getBackgroundColor
-            {
-                // getBackgroundColour/getBackgroundColor
                 return encodeColour( m_terminal.getBackgroundColour() );
-            }
             case 18:
             {
                 // blit
@@ -308,9 +284,7 @@ public class TermAPI implements ILuaAPI
                 // getCursorBlink
                 return new Object[] { m_terminal.getCursorBlink() };
             default:
-            {
                 return null;
-            }
         }
     }
 

src/main/java/dan200/computercraft/core/apis/handles/ArrayByteChannel.java

@@ -6,13 +6,11 @@
 
 package dan200.computercraft.core.apis.handles;
 
-import com.google.common.base.Preconditions;
-
-import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.nio.channels.ClosedChannelException;
 import java.nio.channels.NonWritableChannelException;
 import java.nio.channels.SeekableByteChannel;
+import java.util.Objects;
 
 /**
  * A seekable, readable byte channel which is backed by a simple byte array.
@@ -30,10 +28,10 @@ public class ArrayByteChannel implements SeekableByteChannel
     }
 
     @Override
-    public int read( ByteBuffer destination ) throws IOException
+    public int read( ByteBuffer destination ) throws ClosedChannelException
     {
         if( closed ) throw new ClosedChannelException();
-        Preconditions.checkNotNull( destination, "destination" );
+        Objects.requireNonNull( destination, "destination" );
 
         if( position >= backing.length ) return -1;
 
@@ -44,21 +42,21 @@ public class ArrayByteChannel implements SeekableByteChannel
     }
 
     @Override
-    public int write( ByteBuffer src ) throws IOException
+    public int write( ByteBuffer src ) throws ClosedChannelException
     {
         if( closed ) throw new ClosedChannelException();
         throw new NonWritableChannelException();
     }
 
     @Override
-    public long position() throws IOException
+    public long position() throws ClosedChannelException
     {
         if( closed ) throw new ClosedChannelException();
         return position;
     }
 
     @Override
-    public SeekableByteChannel position( long newPosition ) throws IOException
+    public SeekableByteChannel position( long newPosition ) throws ClosedChannelException
     {
         if( closed ) throw new ClosedChannelException();
         if( newPosition < 0 || newPosition > Integer.MAX_VALUE )
@@ -70,14 +68,14 @@ public class ArrayByteChannel implements SeekableByteChannel
     }
 
     @Override
-    public long size() throws IOException
+    public long size() throws ClosedChannelException
     {
         if( closed ) throw new ClosedChannelException();
         return backing.length;
     }
 
     @Override
-    public SeekableByteChannel truncate( long size ) throws IOException
+    public SeekableByteChannel truncate( long size ) throws ClosedChannelException
     {
         if( closed ) throw new ClosedChannelException();
         throw new NonWritableChannelException();

src/main/java/dan200/computercraft/core/apis/handles/BinaryReadableHandle.java

@@ -38,8 +38,8 @@ public class BinaryReadableHandle extends HandleGeneric
     public BinaryReadableHandle( ReadableByteChannel channel, Closeable closeable )
     {
         super( closeable );
-        this.m_reader = channel;
+        m_reader = channel;
-        this.m_seekable = asSeekable( channel );
+        m_seekable = asSeekable( channel );
     }
 
     public BinaryReadableHandle( ReadableByteChannel channel )

src/main/java/dan200/computercraft/core/apis/handles/BinaryWritableHandle.java

@@ -32,8 +32,8 @@ public class BinaryWritableHandle extends HandleGeneric
     public BinaryWritableHandle( WritableByteChannel channel, Closeable closeable )
     {
         super( closeable );
-        this.m_writer = channel;
+        m_writer = channel;
-        this.m_seekable = asSeekable( channel );
+        m_seekable = asSeekable( channel );
     }
 
     public BinaryWritableHandle( WritableByteChannel channel )

src/main/java/dan200/computercraft/core/apis/handles/EncodedReadableHandle.java

@@ -32,7 +32,7 @@ public class EncodedReadableHandle extends HandleGeneric
     public EncodedReadableHandle( @Nonnull BufferedReader reader, @Nonnull Closeable closable )
     {
         super( closable );
-        this.m_reader = reader;
+        m_reader = reader;
     }
 
     public EncodedReadableHandle( @Nonnull BufferedReader reader )
@@ -84,7 +84,7 @@ public class EncodedReadableHandle extends HandleGeneric
                 checkOpen();
                 try
                 {
-                    StringBuilder result = new StringBuilder( "" );
+                    StringBuilder result = new StringBuilder();
                     String line = m_reader.readLine();
                     while( line != null )
                     {

src/main/java/dan200/computercraft/core/apis/handles/EncodedWritableHandle.java

@@ -27,7 +27,7 @@ public class EncodedWritableHandle extends HandleGeneric
     public EncodedWritableHandle( @Nonnull BufferedWriter writer, @Nonnull Closeable closable )
     {
         super( closable );
-        this.m_writer = writer;
+        m_writer = writer;
     }
 
     public EncodedWritableHandle( @Nonnull BufferedWriter writer )

src/main/java/dan200/computercraft/core/apis/handles/HandleGeneric.java

@@ -26,7 +26,7 @@ public abstract class HandleGeneric implements ILuaObject
 
     protected HandleGeneric( @Nonnull Closeable closable )
     {
-        this.m_closable = closable;
+        m_closable = closable;
     }
 
     protected void checkOpen() throws LuaException
@@ -46,7 +46,7 @@ public abstract class HandleGeneric implements ILuaObject
      *
      * @param channel The channel to seek in
      * @param args    The Lua arguments to process, like Lua's {@code file:seek}.
-     * @return The new position of the file, or null if some error occured.
+     * @return The new position of the file, or null if some error occurred.
      * @throws LuaException If the arguments were invalid
      * @see <a href="https://www.lua.org/manual/5.1/manual.html#pdf-file:seek">{@code file:seek} in the Lua manual.</a>
      */

src/main/java/dan200/computercraft/core/apis/http/CheckUrl.java

@@ -31,7 +31,7 @@ public class CheckUrl extends Resource<CheckUrl>
         super( limiter );
         this.environment = environment;
         this.address = address;
-        this.host = uri.getHost();
+        host = uri.getHost();
     }
 
     public void run()

src/main/java/dan200/computercraft/core/apis/http/Resource.java

@@ -140,6 +140,6 @@ public abstract class Resource<T extends Resource<T>> implements Closeable
     public static void cleanup()
     {
         Reference<?> reference;
-        while( (reference = QUEUE.poll()) != null ) ((CloseReference) reference).resource.close();
+        while( (reference = QUEUE.poll()) != null ) ((CloseReference<?>) reference).resource.close();
     }
 }

src/main/java/dan200/computercraft/core/apis/http/ResourceGroup.java

@@ -32,7 +32,7 @@ public class ResourceGroup<T extends Resource<T>>
 
     public ResourceGroup()
     {
-        this.limit = ZERO;
+        limit = ZERO;
     }
 
     public void startup()

src/main/java/dan200/computercraft/core/apis/http/request/HttpRequest.java

@@ -67,12 +67,12 @@ public class HttpRequest extends Resource<HttpRequest>
         super( limiter );
         this.environment = environment;
         this.address = address;
-        this.postBuffer = postText != null
+        postBuffer = postText != null
             ? Unpooled.wrappedBuffer( postText.getBytes( StandardCharsets.UTF_8 ) )
             : Unpooled.buffer( 0 );
         this.headers = headers;
         this.binary = binary;
-        this.redirects = new AtomicInteger( followRedirects ? MAX_REDIRECTS : 0 );
+        redirects = new AtomicInteger( followRedirects ? MAX_REDIRECTS : 0 );
 
         if( postText != null )
         {
@@ -113,6 +113,7 @@ public class HttpRequest extends Resource<HttpRequest>
     {
         // Validate the URL
         if( url.getScheme() == null ) throw new HTTPRequestException( "Must specify http or https" );
+        if( url.getHost() == null ) throw new HTTPRequestException( "URL malformed" );
 
         String scheme = url.getScheme().toLowerCase( Locale.ROOT );
         if( !scheme.equalsIgnoreCase( "http" ) && !scheme.equalsIgnoreCase( "https" ) )

src/main/java/dan200/computercraft/core/apis/http/request/HttpRequestHandler.java

@@ -37,7 +37,7 @@ public final class HttpRequestHandler extends SimpleChannelInboundHandler<HttpOb
     /**
      * Same as {@link io.netty.handler.codec.MessageAggregator}.
      */
-    private static final int DEFAULT_MAX_COMPOSITEBUFFER_COMPONENTS = 1024;
+    private static final int DEFAULT_MAX_COMPOSITE_BUFFER_COMPONENTS = 1024;
 
     private static final byte[] EMPTY_BYTES = new byte[0];
 
@@ -147,7 +147,7 @@ public final class HttpRequestHandler extends SimpleChannelInboundHandler<HttpOb
 
             if( responseBody == null )
             {
-                responseBody = ctx.alloc().compositeBuffer( DEFAULT_MAX_COMPOSITEBUFFER_COMPONENTS );
+                responseBody = ctx.alloc().compositeBuffer( DEFAULT_MAX_COMPOSITE_BUFFER_COMPONENTS );
             }
 
             ByteBuf partial = content.content();

src/main/java/dan200/computercraft/core/apis/http/websocket/Websocket.java

@@ -95,7 +95,7 @@ public class Websocket extends Resource<Websocket>
         {
             try
             {
-                uri = new URI( "ws://" + uri.toString() );
+                uri = new URI( "ws://" + uri );
             }
             catch( URISyntaxException e )
             {
@@ -186,7 +186,7 @@ public class Websocket extends Resource<Websocket>
 
         WebsocketHandle handle = new WebsocketHandle( this, channel );
         environment().queueEvent( SUCCESS_EVENT, new Object[] { address, handle } );
-        this.websocketHandle = createOwnerReference( handle );
+        websocketHandle = createOwnerReference( handle );
 
         checkClosed();
     }
@@ -216,7 +216,7 @@ public class Websocket extends Resource<Websocket>
         executorFuture = closeFuture( executorFuture );
         connectFuture = closeChannel( connectFuture );
 
-        WeakReference<WebsocketHandle> websocketHandleRef = this.websocketHandle;
+        WeakReference<WebsocketHandle> websocketHandleRef = websocketHandle;
         WebsocketHandle websocketHandle = websocketHandleRef == null ? null : websocketHandleRef.get();
         if( websocketHandle != null ) IoUtil.closeQuietly( websocketHandle );
         this.websocketHandle = null;

src/main/java/dan200/computercraft/core/computer/ApiWrapper.java

@@ -16,7 +16,7 @@ import javax.annotation.Nullable;
 /**
  * A wrapper for {@link ILuaAPI}s which cleans up after a {@link ComputerSystem} when the computer is shutdown.
  */
-public class ApiWrapper implements ILuaAPI
+final class ApiWrapper implements ILuaAPI
 {
     private final ILuaAPI delegate;
     private final ComputerSystem system;

src/main/java/dan200/computercraft/core/computer/Computer.java

@@ -7,54 +7,48 @@
 package dan200.computercraft.core.computer;
 
 import com.google.common.base.Objects;
-import dan200.computercraft.ComputerCraft;
-import dan200.computercraft.api.filesystem.IMount;
-import dan200.computercraft.api.filesystem.IWritableMount;
 import dan200.computercraft.api.lua.ILuaAPI;
-import dan200.computercraft.api.lua.ILuaAPIFactory;
+import dan200.computercraft.api.peripheral.IWorkMonitor;
-import dan200.computercraft.api.peripheral.IPeripheral;
+import dan200.computercraft.core.apis.IAPIEnvironment;
-import dan200.computercraft.core.apis.*;
 import dan200.computercraft.core.filesystem.FileSystem;
-import dan200.computercraft.core.filesystem.FileSystemException;
-import dan200.computercraft.core.lua.CobaltLuaMachine;
-import dan200.computercraft.core.lua.ILuaMachine;
 import dan200.computercraft.core.terminal.Terminal;
 
-import java.io.IOException;
+import java.util.concurrent.atomic.AtomicBoolean;
-import java.io.InputStream;
-import java.util.ArrayList;
-import java.util.List;
 
+/**
+ * Represents a computer which may exist in-world or elsewhere.
+ *
+ * Note, this class has several (read: far, far too many) responsibilities, so can get a little unwieldy at times.
+ *
+ * <ul>
+ * <li>Updates the {@link Environment}.</li>
+ * <li>Keeps track of whether the computer is on and blinking.</li>
+ * <li>Monitors whether the computer's visible state (redstone, on/off/blinking) has changed.</li>
+ * <li>Passes commands and events to the {@link ComputerExecutor}.</li>
+ * <li>Passes main thread tasks to the {@link MainThreadExecutor}.</li>
+ * </ul>
+ */
 public class Computer
 {
-    private enum State
+    private static final int START_DELAY = 50;
-    {
-        Off,
-        Starting,
-        Running,
-        Stopping,
-    }
-
-    private static IMount s_romMount = null;
 
+    // Various properties of the computer
     private int m_id;
     private String m_label = null;
+
+    // Read-only fields about the computer
     private final IComputerEnvironment m_environment;
-
-    private int m_ticksSinceStart = -1;
-    private boolean m_startRequested = false;
-    private State m_state = State.Off;
-    private boolean m_blinking = false;
-
-    private ILuaMachine m_machine = null;
-    private final List<ILuaAPI> m_apis = new ArrayList<>();
-    private final Environment m_internalEnvironment = new Environment( this );
-
     private final Terminal m_terminal;
-    private FileSystem m_fileSystem = null;
+    private final ComputerExecutor executor;
-    private IWritableMount m_rootMount = null;
+    private final MainThreadExecutor serverExecutor;
 
-    private boolean m_externalOutputChanged;
+    // Additional state about the computer and its environment.
+    private boolean m_blinking = false;
+    private final Environment internalEnvironment = new Environment( this );
+    private AtomicBoolean externalOutputChanged = new AtomicBoolean();
+
+    private boolean startRequested;
+    private int m_ticksSinceStart = -1;
 
     public Computer( IComputerEnvironment environment, Terminal terminal, int id )
     {
@@ -62,24 +56,8 @@ public class Computer
         m_environment = environment;
         m_terminal = terminal;
 
-        // Ensure the computer thread is running as required.
+        executor = new ComputerExecutor( this );
-        ComputerThread.start();
+        serverExecutor = new MainThreadExecutor( this );
-
-        // Add all default APIs to the loaded list.
-        m_apis.add( new TermAPI( m_internalEnvironment ) );
-        m_apis.add( new RedstoneAPI( m_internalEnvironment ) );
-        m_apis.add( new FSAPI( m_internalEnvironment ) );
-        m_apis.add( new PeripheralAPI( m_internalEnvironment ) );
-        m_apis.add( new OSAPI( m_internalEnvironment ) );
-        if( ComputerCraft.http_enable ) m_apis.add( new HTTPAPI( m_internalEnvironment ) );
-
-        // Load in the API registered APIs.
-        for( ILuaAPIFactory factory : ApiFactories.getAll() )
-        {
-            ComputerSystem system = new ComputerSystem( m_internalEnvironment );
-            ILuaAPI api = factory.create( system );
-            if( api != null ) m_apis.add( new ApiWrapper( api, system ) );
-        }
     }
 
     IComputerEnvironment getComputerEnvironment()
@@ -89,7 +67,7 @@ public class Computer
 
     FileSystem getFileSystem()
     {
-        return m_fileSystem;
+        return executor.getFileSystem();
     }
 
     Terminal getTerminal()
@@ -99,58 +77,58 @@ public class Computer
 
     public Environment getEnvironment()
     {
-        return m_internalEnvironment;
+        return internalEnvironment;
     }
 
     public IAPIEnvironment getAPIEnvironment()
     {
-        return m_internalEnvironment;
+        return internalEnvironment;
-    }
-
-    public void turnOn()
-    {
-        if( m_state == State.Off ) m_startRequested = true;
-    }
-
-    public void shutdown()
-    {
-        stopComputer( false );
-    }
-
-    public void reboot()
-    {
-        stopComputer( true );
     }
 
     public boolean isOn()
     {
-        synchronized( this )
+        return executor.isOn();
-        {
-            return m_state == State.Running;
-        }
     }
 
-    public void abort( boolean hard )
+    public void turnOn()
     {
-        synchronized( this )
+        startRequested = true;
-        {
+    }
-            if( m_state != State.Off && m_machine != null )
+
-            {
+    public void shutdown()
-                if( hard )
+    {
-                {
+        executor.queueStop( false, false );
-                    m_machine.hardAbort( "Too long without yielding" );
+    }
-                }
+
-                else
+    public void reboot()
-                {
+    {
-                    m_machine.softAbort( "Too long without yielding" );
+        executor.queueStop( true, false );
-                }
-            }
-        }
     }
 
     public void unload()
     {
-        stopComputer( false );
+        executor.queueStop( false, true );
+    }
+
+    public void queueEvent( String event, Object[] args )
+    {
+        executor.queueEvent( event, args );
+    }
+
+    /**
+     * Queue a task to be run on the main thread, using {@link MainThread}.
+     *
+     * @param runnable The task to run
+     * @return If the task was successfully queued (namely, whether there is space on it).
+     */
+    public boolean queueMainThread( Runnable runnable )
+    {
+        return serverExecutor.enqueue( runnable );
+    }
+
+    public IWorkMonitor getMainThreadMonitor()
+    {
+        return serverExecutor;
     }
 
     public int getID()
@@ -182,59 +160,52 @@ public class Computer
         if( !Objects.equal( label, m_label ) )
         {
             m_label = label;
-            m_externalOutputChanged = true;
+            externalOutputChanged.set( true );
         }
     }
 
-    public void advance()
+    public void tick()
     {
-        synchronized( this )
+        // We keep track of the number of ticks since the last start, only
+        if( m_ticksSinceStart >= 0 && m_ticksSinceStart <= START_DELAY ) m_ticksSinceStart++;
+
+        if( startRequested && (m_ticksSinceStart < 0 || m_ticksSinceStart > START_DELAY) )
         {
-            // Start after a number of ticks
+            startRequested = false;
-            if( m_ticksSinceStart >= 0 )
+            if( !executor.isOn() )
             {
-                m_ticksSinceStart++;
+                m_ticksSinceStart = 0;
-            }
+                executor.queueStart();
-            if( m_startRequested && (m_ticksSinceStart < 0 || m_ticksSinceStart > 50) )
-            {
-                startComputer();
-                m_startRequested = false;
-            }
-
-            if( m_state == State.Running )
-            {
-                // Update the environment's internal state.
-                m_internalEnvironment.update();
-
-                // Advance our APIs
-                for( ILuaAPI api : m_apis ) api.update();
             }
         }
 
-        // Prepare to propagate the environment's output to the world.
+        executor.tick();
-        if( m_internalEnvironment.updateOutput() ) m_externalOutputChanged = true;
+
+        // Update the environment's internal state.
+        internalEnvironment.update();
+
+        // Propagate the environment's output to the world.
+        if( internalEnvironment.updateOutput() ) externalOutputChanged.set( true );
 
         // Set output changed if the terminal has changed from blinking to not
-        boolean blinking =
+        boolean blinking = m_terminal.getCursorBlink() &&
-            m_terminal.getCursorBlink() &&
+            m_terminal.getCursorX() >= 0 && m_terminal.getCursorX() < m_terminal.getWidth() &&
-                m_terminal.getCursorX() >= 0 && m_terminal.getCursorX() < m_terminal.getWidth() &&
+            m_terminal.getCursorY() >= 0 && m_terminal.getCursorY() < m_terminal.getHeight();
-                m_terminal.getCursorY() >= 0 && m_terminal.getCursorY() < m_terminal.getHeight();
-
         if( blinking != m_blinking )
         {
             m_blinking = blinking;
-            m_externalOutputChanged = true;
+            externalOutputChanged.set( true );
         }
     }
 
+    void markChanged()
+    {
+        externalOutputChanged.set( true );
+    }
+
     public boolean pollAndResetChanged()
     {
-        synchronized( this )
+        return externalOutputChanged.getAndSet( false );
-        {
-            boolean changed = m_externalOutputChanged;
-            m_externalOutputChanged = false;
-            return changed;
-        }
     }
 
     public boolean isBlinking()
@@ -242,334 +213,8 @@ public class Computer
         return isOn() && m_blinking;
     }
 
-    public IWritableMount getRootMount()
+    public void addApi( ILuaAPI api )
     {
-        if( m_rootMount == null )
+        executor.addApi( api );
-        {
-            m_rootMount = m_environment.createSaveDirMount( "computer/" + assignID(), m_environment.getComputerSpaceLimit() );
-        }
-        return m_rootMount;
     }
-
-    // FileSystem
-
-    private boolean initFileSystem()
-    {
-        // Create the file system
-        assignID();
-        try
-        {
-            m_fileSystem = new FileSystem( "hdd", getRootMount() );
-            if( s_romMount == null ) s_romMount = m_environment.createResourceMount( "computercraft", "lua/rom" );
-            if( s_romMount != null )
-            {
-                m_fileSystem.mount( "rom", "rom", s_romMount );
-                return true;
-            }
-            return false;
-        }
-        catch( FileSystemException e )
-        {
-            ComputerCraft.log.error( "Cannot mount rom", e );
-            return false;
-        }
-    }
-
-    // Peripherals
-
-    public void addAPI( ILuaAPI api )
-    {
-        m_apis.add( api );
-    }
-
-    // Lua
-
-    private void initLua()
-    {
-        // Create the lua machine
-        ILuaMachine machine = new CobaltLuaMachine( this );
-
-        // Add the APIs
-        for( ILuaAPI api : m_apis )
-        {
-            machine.addAPI( api );
-            api.startup();
-        }
-
-        // Load the bios resource
-        InputStream biosStream;
-        try
-        {
-            biosStream = m_environment.createResourceFile( "computercraft", "lua/bios.lua" );
-        }
-        catch( Exception e )
-        {
-            biosStream = null;
-        }
-
-        // Start the machine running the bios resource
-        if( biosStream != null )
-        {
-            machine.loadBios( biosStream );
-            try
-            {
-                biosStream.close();
-            }
-            catch( IOException e )
-            {
-                // meh
-            }
-
-            if( machine.isFinished() )
-            {
-                m_terminal.reset();
-                m_terminal.write( "Error starting bios.lua" );
-                m_terminal.setCursorPos( 0, 1 );
-                m_terminal.write( "ComputerCraft may be installed incorrectly" );
-
-                machine.unload();
-                m_machine = null;
-            }
-            else
-            {
-                m_machine = machine;
-            }
-        }
-        else
-        {
-            m_terminal.reset();
-            m_terminal.write( "Error loading bios.lua" );
-            m_terminal.setCursorPos( 0, 1 );
-            m_terminal.write( "ComputerCraft may be installed incorrectly" );
-
-            machine.unload();
-            m_machine = null;
-        }
-    }
-
-    private void startComputer()
-    {
-        synchronized( this )
-        {
-            if( m_state != State.Off )
-            {
-                return;
-            }
-            m_state = State.Starting;
-            m_externalOutputChanged = true;
-            m_ticksSinceStart = 0;
-        }
-
-        // Turn the computercraft on
-        final Computer computer = this;
-        ComputerThread.queueTask( new ITask()
-        {
-            @Override
-            public Computer getOwner()
-            {
-                return computer;
-            }
-
-            @Override
-            public void execute()
-            {
-                synchronized( this )
-                {
-                    if( m_state != State.Starting )
-                    {
-                        return;
-                    }
-
-                    // Init terminal
-                    m_terminal.reset();
-
-                    // Init filesystem
-                    if( !initFileSystem() )
-                    {
-                        // Init failed, so shutdown
-                        m_terminal.reset();
-                        m_terminal.write( "Error mounting lua/rom" );
-                        m_terminal.setCursorPos( 0, 1 );
-                        m_terminal.write( "ComputerCraft may be installed incorrectly" );
-
-                        m_state = State.Running;
-                        stopComputer( false );
-                        return;
-                    }
-
-                    // Init lua
-                    initLua();
-                    if( m_machine == null )
-                    {
-                        m_terminal.reset();
-                        m_terminal.write( "Error loading bios.lua" );
-                        m_terminal.setCursorPos( 0, 1 );
-                        m_terminal.write( "ComputerCraft may be installed incorrectly" );
-
-                        // Init failed, so shutdown
-                        m_state = State.Running;
-                        stopComputer( false );
-                        return;
-                    }
-
-                    // Start a new state
-                    m_state = State.Running;
-                    m_externalOutputChanged = true;
-                    synchronized( m_machine )
-                    {
-                        m_machine.handleEvent( null, null );
-                    }
-                }
-            }
-        }, computer );
-    }
-
-    private void stopComputer( final boolean reboot )
-    {
-        synchronized( this )
-        {
-            if( m_state != State.Running )
-            {
-                return;
-            }
-            m_state = State.Stopping;
-            m_externalOutputChanged = true;
-        }
-
-        // Turn the computercraft off
-        final Computer computer = this;
-        ComputerThread.queueTask( new ITask()
-        {
-            @Override
-            public Computer getOwner()
-            {
-                return computer;
-            }
-
-            @Override
-            public void execute()
-            {
-                synchronized( this )
-                {
-                    if( m_state != State.Stopping )
-                    {
-                        return;
-                    }
-
-                    // Shutdown our APIs
-                    synchronized( m_apis )
-                    {
-                        for( ILuaAPI api : m_apis )
-                        {
-                            api.shutdown();
-                        }
-                    }
-
-                    // Shutdown terminal and filesystem
-                    if( m_fileSystem != null )
-                    {
-                        m_fileSystem.unload();
-                        m_fileSystem = null;
-                    }
-
-                    if( m_machine != null )
-                    {
-                        m_terminal.reset();
-
-                        synchronized( m_machine )
-                        {
-                            m_machine.unload();
-                            m_machine = null;
-                        }
-                    }
-
-                    // Reset redstone output
-                    m_internalEnvironment.resetOutput();
-
-                    m_state = State.Off;
-                    m_externalOutputChanged = true;
-                    if( reboot )
-                    {
-                        m_startRequested = true;
-                    }
-                }
-            }
-        }, computer );
-    }
-
-    public void queueEvent( final String event, final Object[] arguments )
-    {
-        synchronized( this )
-        {
-            if( m_state != State.Running )
-            {
-                return;
-            }
-        }
-
-        final Computer computer = this;
-        ITask task = new ITask()
-        {
-            @Override
-            public Computer getOwner()
-            {
-                return computer;
-            }
-
-            @Override
-            public void execute()
-            {
-                synchronized( this )
-                {
-                    if( m_state != State.Running )
-                    {
-                        return;
-                    }
-                }
-
-                synchronized( m_machine )
-                {
-                    m_machine.handleEvent( event, arguments );
-                    if( m_machine.isFinished() )
-                    {
-                        m_terminal.reset();
-                        m_terminal.write( "Error resuming bios.lua" );
-                        m_terminal.setCursorPos( 0, 1 );
-                        m_terminal.write( "ComputerCraft may be installed incorrectly" );
-
-                        stopComputer( false );
-                    }
-                }
-            }
-        };
-
-        ComputerThread.queueTask( task, computer );
-    }
-
-    @Deprecated
-    public IPeripheral getPeripheral( int side )
-    {
-        return m_internalEnvironment.getPeripheral( side );
-    }
-
-    @Deprecated
-    public void setPeripheral( int side, IPeripheral peripheral )
-    {
-        m_internalEnvironment.setPeripheral( side, peripheral );
-    }
-
-    @Deprecated
-    public void addAPI( dan200.computercraft.core.apis.ILuaAPI api )
-    {
-        addAPI( (ILuaAPI) api );
-    }
-
-    @Deprecated
-    @SuppressWarnings( "unused" )
-    public void advance( double dt )
-    {
-        advance();
-    }
-
-    public static final String[] s_sideNames = IAPIEnvironment.SIDE_NAMES;
 }

src/main/java/dan200/computercraft/core/computer/ComputerExecutor.java

@@ -0,0 +1,668 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+
+package dan200.computercraft.core.computer;
+
+import dan200.computercraft.ComputerCraft;
+import dan200.computercraft.api.filesystem.IMount;
+import dan200.computercraft.api.filesystem.IWritableMount;
+import dan200.computercraft.api.lua.ILuaAPI;
+import dan200.computercraft.api.lua.ILuaAPIFactory;
+import dan200.computercraft.core.apis.*;
+import dan200.computercraft.core.filesystem.FileSystem;
+import dan200.computercraft.core.filesystem.FileSystemException;
+import dan200.computercraft.core.lua.CobaltLuaMachine;
+import dan200.computercraft.core.lua.ILuaMachine;
+import dan200.computercraft.core.lua.MachineResult;
+import dan200.computercraft.core.terminal.Terminal;
+import dan200.computercraft.core.tracking.Tracking;
+import dan200.computercraft.shared.util.Colour;
+import dan200.computercraft.shared.util.IoUtil;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+import java.io.InputStream;
+import java.util.ArrayDeque;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Queue;
+import java.util.concurrent.atomic.AtomicReference;
+import java.util.concurrent.locks.ReentrantLock;
+
+/**
+ * The main task queue and executor for a single computer. This handles turning on and off a computer, as well as
+ * running events.
+ *
+ * When the computer is instructed to turn on or off, or handle an event, we queue a task and register this to be
+ * executed on the {@link ComputerThread}. Note, as we may be starting many events in a single tick, the external
+ * cannot lock on anything which may be held for a long time.
+ *
+ * The executor is effectively composed of two separate queues. Firstly, we have a "single element" queue
+ * {@link #command} which determines which state the computer should transition too. This is set by
+ * {@link #queueStart()} and {@link #queueStop(boolean, boolean)}.
+ *
+ * When a computer is on, we simply push any events onto to the {@link #eventQueue}.
+ *
+ * Both queues are run from the {@link #work()} method, which tries to execute a command if one exists, or resumes the
+ * machine with an event otherwise.
+ *
+ * One final responsibility for the executor is calling {@link ILuaAPI#update()} every tick, via the {@link #tick()}
+ * method. This should only be called when the computer is actually on ({@link #isOn}).
+ */
+final class ComputerExecutor
+{
+    private static final int QUEUE_LIMIT = 256;
+
+    private static IMount romMount;
+    private static final Object romMountLock = new Object();
+
+    private final Computer computer;
+    private final List<ILuaAPI> apis = new ArrayList<>();
+    final TimeoutState timeout = new TimeoutState();
+
+    private FileSystem fileSystem;
+
+    private ILuaMachine machine;
+
+    /**
+     * Whether the computer is currently on. This is set to false when a shutdown starts, or when turning on completes
+     * (but just before the Lua machine is started).
+     *
+     * @see #isOnLock
+     */
+    private volatile boolean isOn = false;
+
+    /**
+     * The lock to acquire when you need to modify the "on state" of a computer.
+     *
+     * We hold this lock when running any command, and attempt to hold it when updating APIs. This ensures you don't
+     * update APIs while also starting/stopping them.
+     *
+     * @see #isOn
+     * @see #tick()
+     * @see #turnOn()
+     * @see #shutdown()
+     */
+    private final ReentrantLock isOnLock = new ReentrantLock();
+
+    /**
+     * A lock used for any changes to {@link #eventQueue}, {@link #command} or {@link #onComputerQueue}. This will be
+     * used on the main thread, so locks should be kept as brief as possible.
+     */
+    private final Object queueLock = new Object();
+
+    /**
+     * Determines if this executor is present within {@link ComputerThread}.
+     *
+     * @see #queueLock
+     * @see #enqueue()
+     * @see #afterWork()
+     */
+    volatile boolean onComputerQueue = false;
+
+    /**
+     * The amount of time this computer has used on a theoretical machine which shares work evenly amongst computers.
+     *
+     * @see ComputerThread
+     */
+    long virtualRuntime = 0;
+
+    /**
+     * The last time at which we updated {@link #virtualRuntime}.
+     *
+     * @see ComputerThread
+     */
+    long vRuntimeStart;
+
+    /**
+     * The command that {@link #work()} should execute on the computer thread.
+     *
+     * One sets the command with {@link #queueStart()} and {@link #queueStop(boolean, boolean)}. Neither of these will
+     * queue a new event if there is an existing one in the queue.
+     *
+     * Note, if command is not {@code null}, then some command is scheduled to be executed. Otherwise it is not
+     * currently in the queue (or is currently being executed).
+     */
+    private volatile StateCommand command;
+
+    /**
+     * The queue of events which should be executed when this computer is on.
+     *
+     * Note, this should be empty if this computer is off - it is cleared on shutdown and when turning on again.
+     */
+    private final Queue<Event> eventQueue = new ArrayDeque<>( 4 );
+
+    /**
+     * Whether we interrupted an event and so should resume it instead of executing another task.
+     *
+     * @see #work()
+     * @see #resumeMachine(String, Object[])
+     */
+    private boolean interruptedEvent = false;
+
+    /**
+     * Whether this executor has been closed, and will no longer accept any incoming commands or events.
+     *
+     * @see #queueStop(boolean, boolean)
+     */
+    private boolean closed;
+
+    private IWritableMount rootMount;
+
+    /**
+     * The thread the executor is running on. This is non-null when performing work. We use this to ensure we're only
+     * doing one bit of work at one time.
+     *
+     * @see ComputerThread
+     */
+    final AtomicReference<Thread> executingThread = new AtomicReference<>();
+
+    ComputerExecutor( Computer computer )
+    {
+        // Ensure the computer thread is running as required.
+        ComputerThread.start();
+
+        this.computer = computer;
+
+        Environment environment = computer.getEnvironment();
+
+        // Add all default APIs to the loaded list.
+        apis.add( new TermAPI( environment ) );
+        apis.add( new RedstoneAPI( environment ) );
+        apis.add( new FSAPI( environment ) );
+        apis.add( new PeripheralAPI( environment ) );
+        apis.add( new OSAPI( environment ) );
+        if( ComputerCraft.http_enable ) apis.add( new HTTPAPI( environment ) );
+
+        // Load in the externally registered APIs.
+        for( ILuaAPIFactory factory : ApiFactories.getAll() )
+        {
+            ComputerSystem system = new ComputerSystem( environment );
+            ILuaAPI api = factory.create( system );
+            if( api != null ) apis.add( new ApiWrapper( api, system ) );
+        }
+    }
+
+    boolean isOn()
+    {
+        return isOn;
+    }
+
+    FileSystem getFileSystem()
+    {
+        return fileSystem;
+    }
+
+    Computer getComputer()
+    {
+        return computer;
+    }
+
+    void addApi( ILuaAPI api )
+    {
+        apis.add( api );
+    }
+
+    /**
+     * Schedule this computer to be started if not already on.
+     */
+    void queueStart()
+    {
+        synchronized( queueLock )
+        {
+            // We should only schedule a start if we're not currently on and there's turn on.
+            if( closed || isOn || command != null ) return;
+
+            command = StateCommand.TURN_ON;
+            enqueue();
+        }
+    }
+
+    /**
+     * Schedule this computer to be stopped if not already on.
+     *
+     * @param reboot Reboot the computer after stopping
+     * @param close  Close the computer after stopping.
+     * @see #closed
+     */
+    void queueStop( boolean reboot, boolean close )
+    {
+        synchronized( queueLock )
+        {
+            if( closed ) return;
+            closed = close;
+
+            StateCommand newCommand = reboot ? StateCommand.REBOOT : StateCommand.SHUTDOWN;
+
+            // We should only schedule a stop if we're currently on and there's no shutdown pending.
+            if( !isOn || command != null )
+            {
+                // If we're closing, set the command just in case.
+                if( close ) command = newCommand;
+                return;
+            }
+
+            command = newCommand;
+            enqueue();
+        }
+    }
+
+    /**
+     * Abort this whole computer due to a timeout. This will immediately destroy the Lua machine,
+     * and then schedule a shutdown.
+     */
+    void abort()
+    {
+        ILuaMachine machine = this.machine;
+        if( machine != null ) machine.close();
+
+        synchronized( queueLock )
+        {
+            if( closed ) return;
+            command = StateCommand.ABORT;
+            if( isOn ) enqueue();
+        }
+    }
+
+    /**
+     * Queue an event if the computer is on
+     *
+     * @param event The event's name
+     * @param args  The event's arguments
+     */
+    void queueEvent( @Nonnull String event, @Nullable Object[] args )
+    {
+        // Events should be skipped if we're not on.
+        if( !isOn ) return;
+
+        synchronized( queueLock )
+        {
+            // And if we've got some command in the pipeline, then don't queue events - they'll
+            // probably be disposed of anyway.
+            // We also limit the number of events which can be queued.
+            if( closed || command != null || eventQueue.size() >= QUEUE_LIMIT ) return;
+
+            eventQueue.offer( new Event( event, args ) );
+            enqueue();
+        }
+    }
+
+    /**
+     * Add this executor to the {@link ComputerThread} if not already there.
+     */
+    private void enqueue()
+    {
+        synchronized( queueLock )
+        {
+            if( !onComputerQueue ) ComputerThread.queue( this );
+        }
+    }
+
+    /**
+     * Update the internals of the executor.
+     */
+    void tick()
+    {
+        if( isOn && isOnLock.tryLock() )
+        {
+            // This horrific structure means we don't try to update APIs while the state is being changed
+            // (and so they may be running startup/shutdown).
+            // We use tryLock here, as it has minimal delay, and it doesn't matter if we miss an advance at the
+            // beginning or end of a computer's lifetime.
+            try
+            {
+                if( isOn )
+                {
+                    // Advance our APIs.
+                    for( ILuaAPI api : apis ) api.update();
+                }
+            }
+            finally
+            {
+                isOnLock.unlock();
+            }
+        }
+    }
+
+    private IMount getRomMount()
+    {
+        if( romMount != null ) return romMount;
+
+        synchronized( romMountLock )
+        {
+            if( romMount != null ) return romMount;
+            return romMount = computer.getComputerEnvironment().createResourceMount( "computercraft", "lua/rom" );
+        }
+    }
+
+    IWritableMount getRootMount()
+    {
+        if( rootMount == null )
+        {
+            rootMount = computer.getComputerEnvironment().createSaveDirMount(
+                "computer/" + computer.assignID(),
+                computer.getComputerEnvironment().getComputerSpaceLimit()
+            );
+        }
+        return rootMount;
+    }
+
+    private FileSystem createFileSystem()
+    {
+        FileSystem filesystem = null;
+        try
+        {
+            filesystem = new FileSystem( "hdd", getRootMount() );
+
+            IMount romMount = getRomMount();
+            if( romMount == null )
+            {
+                displayFailure( "Cannot mount ROM", null );
+                return null;
+            }
+
+            filesystem.mount( "rom", "rom", romMount );
+            return filesystem;
+        }
+        catch( FileSystemException e )
+        {
+            if( filesystem != null ) filesystem.close();
+            ComputerCraft.log.error( "Cannot mount computer filesystem", e );
+
+            displayFailure( "Cannot mount computer system", null );
+            return null;
+        }
+    }
+
+    private ILuaMachine createLuaMachine()
+    {
+        // Load the bios resource
+        InputStream biosStream = null;
+        try
+        {
+            biosStream = computer.getComputerEnvironment().createResourceFile( "computercraft", "lua/bios.lua" );
+        }
+        catch( Exception ignored )
+        {
+        }
+
+        if( biosStream == null )
+        {
+            displayFailure( "Error loading bios.lua", null );
+            return null;
+        }
+
+        // Create the lua machine
+        ILuaMachine machine = new CobaltLuaMachine( computer, timeout );
+
+        // Add the APIs
+        for( ILuaAPI api : apis ) machine.addAPI( api );
+
+        // Start the machine running the bios resource
+        MachineResult result = machine.loadBios( biosStream );
+        IoUtil.closeQuietly( biosStream );
+
+        if( result.isError() )
+        {
+            machine.close();
+            displayFailure( "Error loading bios.lua", result.getMessage() );
+            return null;
+        }
+
+        return machine;
+    }
+
+    private void turnOn() throws InterruptedException
+    {
+        isOnLock.lockInterruptibly();
+        try
+        {
+            // Reset the terminal and event queue
+            computer.getTerminal().reset();
+            interruptedEvent = false;
+            synchronized( queueLock )
+            {
+                eventQueue.clear();
+            }
+
+            // Init filesystem
+            if( (fileSystem = createFileSystem()) == null )
+            {
+                shutdown();
+                return;
+            }
+
+            // Init APIs
+            for( ILuaAPI api : apis ) api.startup();
+
+            // Init lua
+            if( (machine = createLuaMachine()) == null )
+            {
+                shutdown();
+                return;
+            }
+
+            // Initialisation has finished, so let's mark ourselves as on.
+            isOn = true;
+            computer.markChanged();
+        }
+        finally
+        {
+            isOnLock.unlock();
+        }
+
+        // Now actually start the computer, now that everything is set up.
+        resumeMachine( null, null );
+    }
+
+    private void shutdown() throws InterruptedException
+    {
+        isOnLock.lockInterruptibly();
+        try
+        {
+            isOn = false;
+            interruptedEvent = false;
+            synchronized( queueLock )
+            {
+                eventQueue.clear();
+            }
+
+            // Shutdown Lua machine
+            if( machine != null )
+            {
+                machine.close();
+                machine = null;
+            }
+
+            // Shutdown our APIs
+            for( ILuaAPI api : apis ) api.shutdown();
+
+            // Unload filesystem
+            if( fileSystem != null )
+            {
+                fileSystem.close();
+                fileSystem = null;
+            }
+
+            computer.getEnvironment().resetOutput();
+            computer.markChanged();
+        }
+        finally
+        {
+            isOnLock.unlock();
+        }
+    }
+
+    /**
+     * Called before calling {@link #work()}, setting up any important state.
+     */
+    void beforeWork()
+    {
+        vRuntimeStart = System.nanoTime();
+        timeout.startTimer();
+    }
+
+    /**
+     * Called after executing {@link #work()}.
+     *
+     * @return If we have more work to do.
+     */
+    boolean afterWork()
+    {
+        if( interruptedEvent )
+        {
+            timeout.pauseTimer();
+        }
+        else
+        {
+            timeout.stopTimer();
+        }
+
+        Tracking.addTaskTiming( getComputer(), timeout.nanoCurrent() );
+
+        if( interruptedEvent ) return true;
+
+        synchronized( queueLock )
+        {
+            if( eventQueue.isEmpty() && command == null ) return onComputerQueue = false;
+            return true;
+        }
+    }
+
+    /**
+     * The main worker function, called by {@link ComputerThread}.
+     *
+     * This either executes a {@link StateCommand} or attempts to run an event
+     *
+     * @throws InterruptedException If various locks could not be acquired.
+     * @see #command
+     * @see #eventQueue
+     */
+    void work() throws InterruptedException
+    {
+        if( interruptedEvent )
+        {
+            interruptedEvent = false;
+            if( machine != null )
+            {
+                resumeMachine( null, null );
+                return;
+            }
+        }
+
+        StateCommand command;
+        Event event = null;
+        synchronized( queueLock )
+        {
+            command = this.command;
+            this.command = null;
+
+            // If we've no command, pull something from the event queue instead.
+            if( command == null )
+            {
+                if( !isOn )
+                {
+                    // We're not on and had no command, but we had work queued. This should never happen, so clear
+                    // the event queue just in case.
+                    eventQueue.clear();
+                    return;
+                }
+
+                event = eventQueue.poll();
+            }
+        }
+
+        if( command != null )
+        {
+            switch( command )
+            {
+                case TURN_ON:
+                    if( isOn ) return;
+                    turnOn();
+                    break;
+
+                case SHUTDOWN:
+
+                    if( !isOn ) return;
+                    computer.getTerminal().reset();
+                    shutdown();
+                    break;
+
+                case REBOOT:
+                    if( !isOn ) return;
+                    computer.getTerminal().reset();
+                    shutdown();
+
+                    computer.turnOn();
+                    break;
+
+                case ABORT:
+                    if( !isOn ) return;
+                    displayFailure( "Error running computer", TimeoutState.ABORT_MESSAGE );
+                    shutdown();
+                    break;
+            }
+        }
+        else if( event != null )
+        {
+            resumeMachine( event.name, event.args );
+        }
+    }
+
+    private void displayFailure( String message, String extra )
+    {
+        Terminal terminal = computer.getTerminal();
+        boolean colour = computer.getComputerEnvironment().isColour();
+        terminal.reset();
+
+        // Display our primary error message
+        if( colour ) terminal.setTextColour( 15 - Colour.Red.ordinal() );
+        terminal.write( message );
+
+        if( extra != null )
+        {
+            // Display any additional information. This generally comes from the Lua Machine, such as compilation or
+            // runtime errors.
+            terminal.setCursorPos( 0, terminal.getCursorY() + 1 );
+            terminal.write( extra );
+        }
+
+        // And display our generic "CC may be installed incorrectly" message.
+        terminal.setCursorPos( 0, terminal.getCursorY() + 1 );
+        if( colour ) terminal.setTextColour( 15 - Colour.White.ordinal() );
+        terminal.write( "ComputerCraft may be installed incorrectly" );
+    }
+
+    private void resumeMachine( String event, Object[] args ) throws InterruptedException
+    {
+        MachineResult result = machine.handleEvent( event, args );
+        interruptedEvent = result.isPause();
+        if( !result.isError() ) return;
+
+        displayFailure( "Error running computer", result.getMessage() );
+        shutdown();
+    }
+
+    private enum StateCommand
+    {
+        TURN_ON,
+        SHUTDOWN,
+        REBOOT,
+        ABORT,
+    }
+
+    private static final class Event
+    {
+        final String name;
+        final Object[] args;
+
+        private Event( String name, Object[] args )
+        {
+            this.name = name;
+            this.args = args;
+        }
+    }
+}

src/main/java/dan200/computercraft/core/computer/ComputerSide.java

@@ -0,0 +1,56 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+
+package dan200.computercraft.core.computer;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
+/**
+ * A side on a computer. Unlike {@link net.minecraft.util.EnumFacing}, this is relative to the direction the computer is
+ * facing..
+ */
+public enum ComputerSide
+{
+    BOTTOM( "bottom" ),
+    TOP( "top" ),
+    BACK( "back" ),
+    FRONT( "front" ),
+    RIGHT( "right" ),
+    LEFT( "left" );
+
+    public static final String[] NAMES = new String[] { "bottom", "top", "back", "front", "right", "left" };
+
+    public static final int COUNT = 6;
+
+    private static final ComputerSide[] VALUES = values();
+
+    private final String name;
+
+    ComputerSide( String name ) {this.name = name;}
+
+    @Nonnull
+    public static ComputerSide valueOf( int side )
+    {
+        return VALUES[side];
+    }
+
+    @Nullable
+    public static ComputerSide valueOfInsensitive( @Nonnull String name )
+    {
+        for( ComputerSide side : VALUES )
+        {
+            if( side.name.equalsIgnoreCase( name ) ) return side;
+        }
+
+        return null;
+    }
+
+    public String getName()
+    {
+        return name;
+    }
+}

src/main/java/dan200/computercraft/core/computer/ComputerSystem.java

@@ -18,7 +18,7 @@ import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 
 /**
- * Implementation of {@link IComputerAccess}/{@link IComputerSystem} for external APIs.
+ * Implementation of {@link IComputerAccess}/{@link IComputerSystem} for usage by externally registered APIs.
  *
  * @see dan200.computercraft.api.ComputerCraftAPI#registerAPIFactory(ILuaAPIFactory)
  * @see ILuaAPIFactory
@@ -26,12 +26,12 @@ import javax.annotation.Nullable;
  */
 public class ComputerSystem extends ComputerAccess implements IComputerSystem
 {
-    private final IAPIEnvironment m_environment;
+    private final IAPIEnvironment environment;
 
-    ComputerSystem( IAPIEnvironment m_environment )
+    ComputerSystem( IAPIEnvironment environment )
     {
-        super( m_environment );
+        super( environment );
-        this.m_environment = m_environment;
+        this.environment = environment;
     }
 
     @Nonnull
@@ -45,7 +45,7 @@ public class ComputerSystem extends ComputerAccess implements IComputerSystem
     @Override
     public IFileSystem getFileSystem()
     {
-        FileSystem fs = m_environment.getFileSystem();
+        FileSystem fs = environment.getFileSystem();
         return fs == null ? null : fs.getMountWrapper();
     }
 
@@ -53,6 +53,6 @@ public class ComputerSystem extends ComputerAccess implements IComputerSystem
     @Override
     public String getLabel()
     {
-        return m_environment.getLabel();
+        return environment.getLabel();
     }
 }

src/main/java/dan200/computercraft/core/computer/ComputerThread.java

@@ -7,153 +7,351 @@
 package dan200.computercraft.core.computer;
 
 import dan200.computercraft.ComputerCraft;
-import dan200.computercraft.core.tracking.Tracking;
 import dan200.computercraft.shared.util.ThreadUtils;
 
-import java.util.HashSet;
+import javax.annotation.Nonnull;
-import java.util.Set;
+import javax.annotation.Nullable;
-import java.util.WeakHashMap;
+import java.util.TreeSet;
-import java.util.concurrent.BlockingQueue;
-import java.util.concurrent.LinkedBlockingQueue;
 import java.util.concurrent.ThreadFactory;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicReference;
+import java.util.concurrent.locks.Condition;
 import java.util.concurrent.locks.LockSupport;
+import java.util.concurrent.locks.ReentrantLock;
 
-public class ComputerThread
+import static dan200.computercraft.core.computer.TimeoutState.ABORT_TIMEOUT;
+import static dan200.computercraft.core.computer.TimeoutState.TIMEOUT;
+
+/**
+ * Responsible for running all tasks from a {@link Computer}.
+ *
+ * This is split into two components: the {@link TaskRunner}s, which pull an executor from the queue and execute it, and
+ * a single {@link Monitor} which observes all runners and kills them if they have not been terminated by
+ * {@link TimeoutState#isSoftAborted()}.
+ *
+ * Computers are executed using a priority system, with those who have spent less time executing having a higher
+ * priority than those hogging the thread. This, combined with {@link TimeoutState#isPaused()} means we can reduce the
+ * risk of badly behaved computers stalling execution for everyone else.
+ *
+ * This is done using an implementation of Linux's Completely Fair Scheduler. When a computer executes, we compute what
+ * share of execution time it has used (time executed/number of tasks). We then pick the computer who has the least
+ * "virtual execution time" (aka {@link ComputerExecutor#virtualRuntime}).
+ *
+ * When adding a computer to the queue, we make sure its "virtual runtime" is at least as big as the smallest runtime.
+ * This means that adding computers which have slept a lot do not then have massive priority over everyone else. See
+ * {@link #queue(ComputerExecutor)} for how this is implemented.
+ *
+ * In reality, it's unlikely that more than a few computers are waiting to execute at once, so this will not have much
+ * effect unless you have a computer hogging execution time. However, it is pretty effective in those situations.
+ *
+ * @see TimeoutState For how hard timeouts are handled.
+ * @see ComputerExecutor For how computers actually do execution.
+ */
+public final class ComputerThread
 {
-    private static final int QUEUE_LIMIT = 256;
+    /**
+     * How often the computer thread monitor should run, in milliseconds
+     *
+     * @see Monitor
+     */
+    private static final int MONITOR_WAKEUP = 100;
 
     /**
-     * Lock used for modifications to the object
+     * The target latency between executing two tasks on a single machine.
+     *
+     * An average tick takes 50ms, and so we ideally need to have handled a couple of events within that window in order
+     * to have a perceived low latency.
      */
-    private static final Object s_stateLock = new Object();
+    private static final long DEFAULT_LATENCY = TimeUnit.MILLISECONDS.toNanos( 50 );
 
     /**
-     * Lock for various task operations
+     * The minimum value that {@link #DEFAULT_LATENCY} can have when scaled.
+     *
+     * From statistics gathered on SwitchCraft, almost all machines will execute under 15ms, 75% under 1.5ms, with the
+     * mean being about 3ms. Most computers shouldn't be too impacted with having such a short period to execute in.
      */
-    private static final Object s_taskLock = new Object();
+    private static final long DEFAULT_MIN_PERIOD = TimeUnit.MILLISECONDS.toNanos( 5 );
 
     /**
-     * Map of objects to task list
+     * The maximum number of tasks before we have to start scaling latency linearly.
      */
-    private static final WeakHashMap<Object, BlockingQueue<ITask>> s_computerTaskQueues = new WeakHashMap<>();
+    private static final long LATENCY_MAX_TASKS = DEFAULT_LATENCY / DEFAULT_MIN_PERIOD;
+
+    /**
+     * Lock used for modifications to the array of current threads.
+     */
+    private static final Object threadLock = new Object();
+
+    /**
+     * Whether the computer thread system is currently running
+     */
+    private static volatile boolean running = false;
+
+    /**
+     * The current task manager.
+     */
+    private static Thread monitor;
+
+    /**
+     * The array of current runners, and their owning threads.
+     */
+    private static TaskRunner[] runners;
+
+    private static long latency;
+    private static long minPeriod;
+
+    private static final ReentrantLock computerLock = new ReentrantLock();
+
+    private static final Condition hasWork = computerLock.newCondition();
 
     /**
      * Active queues to execute
      */
-    private static final BlockingQueue<BlockingQueue<ITask>> s_computerTasksActive = new LinkedBlockingQueue<>();
+    private static final TreeSet<ComputerExecutor> computerQueue = new TreeSet<>( ( a, b ) -> {
-    private static final Set<BlockingQueue<ITask>> s_computerTasksActiveSet = new HashSet<>();
+        if( a == b ) return 0; // Should never happen, but let's be consistent here
+
+        long at = a.virtualRuntime, bt = b.virtualRuntime;
+        if( at == bt ) return Integer.compare( a.hashCode(), b.hashCode() );
+        return at < bt ? -1 : 1;
+    } );
 
     /**
-     * The default object for items which don't have an owner
+     * The minimum {@link ComputerExecutor#virtualRuntime} time on the tree.
      */
-    private static final Object s_defaultOwner = new Object();
+    private static long minimumVirtualRuntime = 0;
 
-    /**
+    private static final ThreadFactory monitorFactory = ThreadUtils.factory( "Computer-Monitor" );
-     * Whether the thread is stopped or should be stopped
+    private static final ThreadFactory runnerFactory = ThreadUtils.factory( "Computer-Runner" );
-     */
-    private static boolean s_stopped = false;
 
-    /**
+    private ComputerThread() {}
-     * The thread tasks execute on
-     */
-    private static Thread[] s_threads = null;
-
-    private static final ThreadFactory s_ManagerFactory = ThreadUtils.factory( "Computer-Manager" );
-    private static final ThreadFactory s_RunnerFactory = ThreadUtils.factory( "Computer-Runner" );
 
     /**
      * Start the computer thread
      */
-    public static void start()
+    static void start()
     {
-        synchronized( s_stateLock )
+        synchronized( threadLock )
         {
-            s_stopped = false;
+            running = true;
-            if( s_threads == null || s_threads.length != ComputerCraft.computer_threads )
+            if( monitor == null || !monitor.isAlive() ) (monitor = monitorFactory.newThread( new Monitor() )).start();
+
+            if( runners == null )
             {
-                s_threads = new Thread[ComputerCraft.computer_threads];
+                // TODO: Change the runners length on config reloads
+                runners = new TaskRunner[ComputerCraft.computer_threads];
+
+                // latency and minPeriod are scaled by 1 + floor(log2(threads)). We can afford to execute tasks for
+                // longer when executing on more than one thread.
+                long factor = 64 - Long.numberOfLeadingZeros( runners.length );
+                latency = DEFAULT_LATENCY * factor;
+                minPeriod = DEFAULT_MIN_PERIOD * factor;
             }
 
-            for( int i = 0; i < s_threads.length; i++ )
+            for( int i = 0; i < runners.length; i++ )
             {
-                Thread thread = s_threads[i];
+                TaskRunner runner = runners[i];
-                if( thread == null || !thread.isAlive() )
+                if( runner == null || runner.owner == null || !runner.owner.isAlive() )
                 {
-                    (s_threads[i] = s_ManagerFactory.newThread( new TaskExecutor() )).start();
+                    // Mark the old runner as dead, just in case.
+                    if( runner != null ) runner.running = false;
+                    // And start a new runner
+                    runnerFactory.newThread( runners[i] = new TaskRunner() ).start();
                 }
             }
         }
     }
 
     /**
-     * Attempt to stop the computer thread
+     * Attempt to stop the computer thread. This interrupts each runner, and clears the task queue.
      */
     public static void stop()
     {
-        synchronized( s_stateLock )
+        synchronized( threadLock )
         {
-            if( s_threads != null )
+            running = false;
+            if( runners != null )
             {
-                s_stopped = true;
+                for( TaskRunner runner : runners )
-                for( Thread thread : s_threads )
                 {
-                    if( thread != null && thread.isAlive() )
+                    if( runner == null ) continue;
-                    {
+
-                        thread.interrupt();
+                    runner.running = false;
-                    }
+                    if( runner.owner != null ) runner.owner.interrupt();
                 }
             }
         }
 
-        synchronized( s_taskLock )
+        computerLock.lock();
+        try
         {
-            s_computerTaskQueues.clear();
+            computerQueue.clear();
-            s_computerTasksActive.clear();
+        }
-            s_computerTasksActiveSet.clear();
+        finally
+        {
+            computerLock.unlock();
         }
     }
 
     /**
-     * Queue a task to execute on the thread
+     * Mark a computer as having work, enqueuing it on the thread
      *
-     * @param task     The task to execute
+     * You must be holding {@link ComputerExecutor}'s {@code queueLock} when calling this method - it should only
-     * @param computer The computer to execute it on, use {@code null} to execute on the default object.
+     * be called from {@code enqueue}.
+     *
+     * @param executor The computer to execute work on.
      */
-    public static void queueTask( ITask task, Computer computer )
+    static void queue( @Nonnull ComputerExecutor executor )
     {
-        Object queueObject = computer == null ? s_defaultOwner : computer;
+        computerLock.lock();
-
+        try
-        BlockingQueue<ITask> queue;
-        synchronized( s_computerTaskQueues )
         {
-            queue = s_computerTaskQueues.get( queueObject );
+            if( executor.onComputerQueue ) throw new IllegalStateException( "Cannot queue already queued executor" );
-            if( queue == null )
+            executor.onComputerQueue = true;
+
+            updateRuntimes( null );
+
+            // We're not currently on the queue, so update its current execution time to
+            // ensure its at least as high as the minimum.
+            long newRuntime = minimumVirtualRuntime;
+
+            if( executor.virtualRuntime == 0 )
             {
-                s_computerTaskQueues.put( queueObject, queue = new LinkedBlockingQueue<>( QUEUE_LIMIT ) );
+                // Slow down new computers a little bit.
+                newRuntime += scaledPeriod();
+            }
+            else
+            {
+                // Give a small boost to computers which have slept a little.
+                newRuntime -= latency / 2;
+            }
+
+            executor.virtualRuntime = Math.max( newRuntime, executor.virtualRuntime );
+
+            // Add to the queue, and signal the workers.
+            computerQueue.add( executor );
+            hasWork.signal();
+        }
+        finally
+        {
+            computerLock.unlock();
+        }
+    }
+
+
+    /**
+     * Update the {@link ComputerExecutor#virtualRuntime}s of all running tasks, and then update the
+     * {@link #minimumVirtualRuntime} based on the current tasks.
+     *
+     * This is called before queueing tasks, to ensure that {@link #minimumVirtualRuntime} is up-to-date.
+     */
+    private static void updateRuntimes( @Nullable ComputerExecutor current )
+    {
+        long minRuntime = Long.MAX_VALUE;
+
+        // If we've a task on the queue, use that as our base time.
+        if( !computerQueue.isEmpty() ) minRuntime = computerQueue.first().virtualRuntime;
+
+        // Update all the currently executing tasks
+        long now = System.nanoTime();
+        int tasks = 1 + computerQueue.size();
+        TaskRunner[] currentRunners = runners;
+        if( currentRunners != null )
+        {
+            for( TaskRunner runner : currentRunners )
+            {
+                if( runner == null ) continue;
+                ComputerExecutor executor = runner.currentExecutor.get();
+                if( executor == null ) continue;
+
+                // We do two things here: first we update the task's virtual runtime based on when we
+                // last checked, and then we check the minimum.
+                minRuntime = Math.min( minRuntime, executor.virtualRuntime += (now - executor.vRuntimeStart) / tasks );
+                executor.vRuntimeStart = now;
             }
         }
 
-        synchronized( s_taskLock )
+        // And update the most recently executed one (if set).
+        if( current != null )
         {
-            if( queue.offer( task ) && !s_computerTasksActiveSet.contains( queue ) )
+            minRuntime = Math.min( minRuntime, current.virtualRuntime += (now - current.vRuntimeStart) / tasks );
-            {
+        }
-                s_computerTasksActive.add( queue );
+
-                s_computerTasksActiveSet.add( queue );
+        if( minRuntime > minimumVirtualRuntime && minRuntime < Long.MAX_VALUE )
-            }
+        {
+            minimumVirtualRuntime = minRuntime;
         }
     }
 
     /**
-     * Responsible for pulling and managing computer tasks. This pulls a task from {@link #s_computerTasksActive},
+     * Ensure the "currently working" state of the executor is reset, the timings are updated, and then requeue the
-     * creates a new thread using {@link TaskRunner} or reuses a previous one and uses that to execute the task.
+     * executor if needed.
      *
-     * If the task times out, then it will attempt to interrupt the {@link TaskRunner} instance.
+     * @param runner   The runner this task was on.
+     * @param executor The executor to requeue
      */
-    private static final class TaskExecutor implements Runnable
+    private static void afterWork( TaskRunner runner, ComputerExecutor executor )
     {
-        private TaskRunner runner;
+        // Clear the executor's thread.
-        private Thread thread;
+        Thread currentThread = executor.executingThread.getAndSet( null );
+        if( currentThread != runner.owner )
+        {
+            ComputerCraft.log.error(
+                "Expected computer #{} to be running on {}, but already running on {}. This is a SERIOUS bug, please report with your debug.log.",
+                executor.getComputer().getID(), runner.owner.getName(), currentThread == null ? "nothing" : currentThread.getName()
+            );
+        }
 
+        computerLock.lock();
+        try
+        {
+            updateRuntimes( executor );
+
+            // If we've no more tasks, just return.
+            if( !executor.afterWork() ) return;
+
+            // Otherwise, add to the queue, and signal any waiting workers.
+            computerQueue.add( executor );
+            hasWork.signal();
+        }
+        finally
+        {
+            computerLock.unlock();
+        }
+    }
+
+    /**
+     * The scaled period for a single task
+     *
+     * @return The scaled period for the task
+     * @see #DEFAULT_LATENCY
+     * @see #DEFAULT_MIN_PERIOD
+     * @see #LATENCY_MAX_TASKS
+     */
+    static long scaledPeriod()
+    {
+        // +1 to include the current task
+        int count = 1 + computerQueue.size();
+        return count < LATENCY_MAX_TASKS ? latency / count : minPeriod;
+    }
+
+    /**
+     * Determine if the thread has computers queued up
+     *
+     * @return If we have work queued up.
+     */
+    static boolean hasPendingWork()
+    {
+        return !computerQueue.isEmpty();
+    }
+
+    /**
+     * Observes all currently active {@link TaskRunner}s and terminates their tasks once they have exceeded the hard
+     * abort limit.
+     *
+     * @see TimeoutState
+     */
+    private static final class Monitor implements Runnable
+    {
         @Override
         public void run()
         {
@@ -161,201 +359,171 @@ public class ComputerThread
             {
                 while( true )
                 {
-                    // Wait for an active queue to execute
+                    Thread.sleep( MONITOR_WAKEUP );
-                    BlockingQueue<ITask> queue = s_computerTasksActive.take();
 
-                    // If threads should be stopped then return
+                    TaskRunner[] currentRunners = ComputerThread.runners;
-                    synchronized( s_stateLock )
+                    if( currentRunners != null )
                     {
-                        if( s_stopped ) return;
+                        for( int i = 0; i < currentRunners.length; i++ )
-                    }
+                        {
+                            TaskRunner runner = currentRunners[i];
+                            // If we've no runner, skip.
+                            if( runner == null ) continue;
 
-                    execute( queue );
+                            // If the runner has no work, skip
+                            ComputerExecutor executor = runner.currentExecutor.get();
+                            if( executor == null ) continue;
+
+                            // If we're still within normal execution times (TIMEOUT) or soft abort (ABORT_TIMEOUT),
+                            // then we can let the Lua machine do its work.
+                            long afterStart = executor.timeout.nanoCumulative();
+                            long afterHardAbort = afterStart - TIMEOUT - ABORT_TIMEOUT;
+                            if( afterHardAbort < 0 ) continue;
+
+                            // Set the hard abort flag.
+                            executor.timeout.hardAbort();
+                            executor.abort();
+
+                            if( afterHardAbort >= ABORT_TIMEOUT )
+                            {
+                                // If we've hard aborted but we're still not dead, dump the stack trace and interrupt
+                                // the task.
+                                timeoutTask( executor, runner.owner, afterStart );
+                                runner.owner.interrupt();
+                            }
+                            else if( afterHardAbort >= ABORT_TIMEOUT * 2 )
+                            {
+                                // If we've hard aborted and interrupted, and we're still not dead, then mark the runner
+                                // as dead, finish off the task, and spawn a new runner.
+                                timeoutTask( executor, runner.owner, afterStart );
+                                runner.running = false;
+                                runner.owner.interrupt();
+
+                                ComputerExecutor thisExecutor = runner.currentExecutor.getAndSet( null );
+                                if( thisExecutor != null ) afterWork( runner, executor );
+
+                                synchronized( threadLock )
+                                {
+                                    if( running && runners.length > i && runners[i] == runner )
+                                    {
+                                        runnerFactory.newThread( currentRunners[i] = new TaskRunner() ).start();
+                                    }
+                                }
+                            }
+                        }
+                    }
                 }
             }
             catch( InterruptedException ignored )
             {
-                Thread.currentThread().interrupt();
-            }
-        }
-
-        private void execute( BlockingQueue<ITask> queue ) throws InterruptedException
-        {
-            ITask task = queue.remove();
-
-            if( thread == null || !thread.isAlive() )
-            {
-                runner = new TaskRunner();
-                (thread = s_RunnerFactory.newThread( runner )).start();
-            }
-
-            long start = System.nanoTime();
-
-            // Execute the task
-            runner.submit( task );
-
-            try
-            {
-                // If we timed out rather than exiting:
-                boolean done = runner.await( 7000 );
-                if( !done )
-                {
-                    // Attempt to soft then hard abort
-                    Computer computer = task.getOwner();
-                    if( computer != null )
-                    {
-                        computer.abort( false );
-
-                        done = runner.await( 1500 );
-                        if( !done )
-                        {
-                            computer.abort( true );
-                            done = runner.await( 1500 );
-                        }
-                    }
-
-                    // Interrupt the thread
-                    if( !done )
-                    {
-                        if( ComputerCraft.logPeripheralErrors )
-                        {
-                            long time = System.nanoTime() - start;
-                            StringBuilder builder = new StringBuilder( "Terminating " );
-                            if( computer != null )
-                            {
-                                builder.append( "computer #" ).append( computer.getID() );
-                            }
-                            else
-                            {
-                                builder.append( "unknown computer" );
-                            }
-
-                            {
-                                builder.append( " due to timeout (running for " )
-                                    .append( time / 1e9 )
-                                    .append( " seconds). This is NOT a bug, but may mean a computer is misbehaving. " )
-                                    .append( thread.getName() )
-                                    .append( " is currently " )
-                                    .append( thread.getState() );
-                                Object blocking = LockSupport.getBlocker( thread );
-                                if( blocking != null ) builder.append( "\n  on " ).append( blocking );
-
-                                for( StackTraceElement element : thread.getStackTrace() )
-                                {
-                                    builder.append( "\n  at " ).append( element );
-                                }
-                            }
-
-                            ComputerCraft.log.warn( builder.toString() );
-                        }
-
-                        thread.interrupt();
-                        thread = null;
-                        runner = null;
-                    }
-                }
-            }
-            finally
-            {
-                long stop = System.nanoTime();
-                Computer computer = task.getOwner();
-                if( computer != null ) Tracking.addTaskTiming( computer, stop - start );
-
-                // Re-add it back onto the queue or remove it
-                synchronized( s_taskLock )
-                {
-                    if( queue.isEmpty() )
-                    {
-                        s_computerTasksActiveSet.remove( queue );
-                    }
-                    else
-                    {
-                        s_computerTasksActive.add( queue );
-                    }
-                }
             }
         }
     }
 
     /**
-     * Responsible for the actual running of tasks. It waitin for the {@link TaskRunner#input} semaphore to be
+     * Pulls tasks from the {@link #computerQueue} queue and runs them.
-     * triggered, consumes a task and then triggers {@link TaskRunner#finished}.
+     *
+     * This is responsible for running the {@link ComputerExecutor#work()}, {@link ComputerExecutor#beforeWork()} and
+     * {@link ComputerExecutor#afterWork()} functions. Everything else is either handled by the executor, timeout
+     * state or monitor.
      */
     private static final class TaskRunner implements Runnable
     {
-        private final Semaphore input = new Semaphore();
+        Thread owner;
-        private final Semaphore finished = new Semaphore();
+        volatile boolean running = true;
-        private ITask task;
+
+        final AtomicReference<ComputerExecutor> currentExecutor = new AtomicReference<>();
 
         @Override
         public void run()
         {
-            try
+            owner = Thread.currentThread();
+
+            tasks:
+            while( running && ComputerThread.running )
             {
-                while( true )
+                // Wait for an active queue to execute
+                ComputerExecutor executor;
+                try
                 {
-                    input.await();
+                    computerLock.lockInterruptibly();
                     try
                     {
-                        task.execute();
+                        while( computerQueue.isEmpty() ) hasWork.await();
+                        executor = computerQueue.pollFirst();
+                        assert executor != null : "hasWork should ensure we never receive null work";
                     }
-                    catch( RuntimeException e )
+                    finally
                     {
-                        ComputerCraft.log.error( "Error running task.", e );
+                        computerLock.unlock();
                     }
-                    task = null;
+                }
-                    finished.signal();
+                catch( InterruptedException ignored )
+                {
+                    // If we've been interrupted, our running flag has probably been reset, so we'll
+                    // just jump into the next iteration.
+                    continue;
+                }
+
+                // If we're trying to executing some task on this computer while someone else is doing work, something
+                // is seriously wrong.
+                while( !executor.executingThread.compareAndSet( null, owner ) )
+                {
+                    Thread existing = executor.executingThread.get();
+                    if( existing != null )
+                    {
+                        ComputerCraft.log.error(
+                            "Trying to run computer #{} on thread {}, but already running on {}. This is a SERIOUS bug, please report with your debug.log.",
+                            executor.getComputer().getID(), owner.getName(), existing.getName()
+                        );
+                        continue tasks;
+                    }
+                }
+
+                // Reset the timers
+                executor.beforeWork();
+
+                // And then set the current executor. It's important to do it afterwards, as otherwise we introduce
+                // race conditions with the monitor.
+                currentExecutor.set( executor );
+
+                // Execute the task
+                try
+                {
+                    executor.work();
+                }
+                catch( Exception e )
+                {
+                    ComputerCraft.log.error( "Error running task on computer #" + executor.getComputer().getID(), e );
+                }
+                finally
+                {
+                    ComputerExecutor thisExecutor = currentExecutor.getAndSet( null );
+                    if( thisExecutor != null ) afterWork( this, executor );
                 }
             }
-            catch( InterruptedException e )
-            {
-                ComputerCraft.log.error( "Error running task.", e );
-                Thread.currentThread().interrupt();
-            }
-        }
-
-        void submit( ITask task )
-        {
-            this.task = task;
-            input.signal();
-        }
-
-        boolean await( long timeout ) throws InterruptedException
-        {
-            return finished.await( timeout );
         }
     }
 
-    /**
+    private static void timeoutTask( ComputerExecutor executor, Thread thread, long time )
-     * A simple method to allow awaiting/providing a signal.
-     *
-     * Java does provide similar classes, but I only needed something simple.
-     */
-    private static final class Semaphore
     {
-        private volatile boolean state = false;
+        if( !ComputerCraft.logPeripheralErrors ) return;
 
-        synchronized void signal()
+        StringBuilder builder = new StringBuilder()
+            .append( "Terminating computer #" ).append( executor.getComputer().getID() )
+            .append( " due to timeout (running for " ).append( time * 1e-9 )
+            .append( " seconds). This is NOT a bug, but may mean a computer is misbehaving. " )
+            .append( thread.getName() )
+            .append( " is currently " )
+            .append( thread.getState() );
+        Object blocking = LockSupport.getBlocker( thread );
+        if( blocking != null ) builder.append( "\n  on " ).append( blocking );
+
+        for( StackTraceElement element : thread.getStackTrace() )
         {
-            state = true;
+            builder.append( "\n  at " ).append( element );
-            notify();
         }
 
-        synchronized void await() throws InterruptedException
+        ComputerCraft.log.warn( builder.toString() );
-        {
-            while( !state ) wait();
-            state = false;
-        }
-
-        synchronized boolean await( long timeout ) throws InterruptedException
-        {
-            if( !state )
-            {
-                wait( timeout );
-                if( !state ) return false;
-            }
-            state = false;
-            return true;
-        }
     }
 }

src/main/java/dan200/computercraft/core/computer/Environment.java

@@ -7,6 +7,7 @@
 package dan200.computercraft.core.computer;
 
 import dan200.computercraft.api.peripheral.IPeripheral;
+import dan200.computercraft.api.peripheral.IWorkMonitor;
 import dan200.computercraft.core.apis.IAPIEnvironment;
 import dan200.computercraft.core.filesystem.FileSystem;
 import dan200.computercraft.core.terminal.Terminal;
@@ -21,7 +22,7 @@ import java.util.Arrays;
  *
  * This handles storing and updating of peripherals and redstone.
  *
- * <h2>Redstone</h2>
+ * <h1>Redstone</h1>
  * We holds three kinds of arrays for redstone, in normal and bundled versions:
  * <ul>
  * <li>{@link #internalOutput} is the redstone output which the computer has currently set. This is read on both
@@ -32,7 +33,7 @@ import java.util.Arrays;
  * thread.</li>
  * </ul>
  *
- * <h2>Peripheral</h2>
+ * <h1>Peripheral</h1>
  * We also keep track of peripherals. These are read on both threads, and only written on the main thread.
  */
 public final class Environment implements IAPIEnvironment
@@ -40,17 +41,17 @@ public final class Environment implements IAPIEnvironment
     private final Computer computer;
 
     private boolean internalOutputChanged = false;
-    private final int[] internalOutput = new int[SIDE_COUNT];
+    private final int[] internalOutput = new int[ComputerSide.COUNT];
-    private final int[] internalBundledOutput = new int[SIDE_COUNT];
+    private final int[] internalBundledOutput = new int[ComputerSide.COUNT];
 
-    private final int[] externalOutput = new int[SIDE_COUNT];
+    private final int[] externalOutput = new int[ComputerSide.COUNT];
-    private final int[] externalBundledOutput = new int[SIDE_COUNT];
+    private final int[] externalBundledOutput = new int[ComputerSide.COUNT];
 
     private boolean inputChanged = false;
-    private final int[] input = new int[SIDE_COUNT];
+    private final int[] input = new int[ComputerSide.COUNT];
-    private final int[] bundledInput = new int[SIDE_COUNT];
+    private final int[] bundledInput = new int[ComputerSide.COUNT];
 
-    private final IPeripheral[] peripherals = new IPeripheral[SIDE_COUNT];
+    private final IPeripheral[] peripherals = new IPeripheral[ComputerSide.COUNT];
     private IPeripheralChangeListener peripheralListener = null;
 
     Environment( Computer computer )
@@ -58,13 +59,6 @@ public final class Environment implements IAPIEnvironment
         this.computer = computer;
     }
 
-    @Nonnull
-    @Override
-    public Computer getComputer()
-    {
-        return computer;
-    }
-
     @Override
     public int getComputerID()
     {
@@ -78,6 +72,13 @@ public final class Environment implements IAPIEnvironment
         return computer.getComputerEnvironment();
     }
 
+    @Nonnull
+    @Override
+    public IWorkMonitor getMainThreadMonitor()
+    {
+        return computer.getMainThreadMonitor();
+    }
+
     @Nonnull
     @Override
     public Terminal getTerminal()
@@ -110,85 +111,89 @@ public final class Environment implements IAPIEnvironment
     }
 
     @Override
-    public int getInput( int side )
+    public int getInput( ComputerSide side )
     {
-        return input[side];
+        return input[side.ordinal()];
     }
 
     @Override
-    public int getBundledInput( int side )
+    public int getBundledInput( ComputerSide side )
     {
-        return bundledInput[side];
+        return bundledInput[side.ordinal()];
     }
 
     @Override
-    public void setOutput( int side, int output )
+    public void setOutput( ComputerSide side, int output )
     {
+        int index = side.ordinal();
         synchronized( internalOutput )
         {
-            if( internalOutput[side] != output )
+            if( internalOutput[index] != output )
             {
-                internalOutput[side] = output;
+                internalOutput[index] = output;
                 internalOutputChanged = true;
             }
         }
     }
 
     @Override
-    public int getOutput( int side )
+    public int getOutput( ComputerSide side )
     {
         synchronized( internalOutput )
         {
-            return computer.isOn() ? internalOutput[side] : 0;
+            return computer.isOn() ? internalOutput[side.ordinal()] : 0;
         }
     }
 
     @Override
-    public void setBundledOutput( int side, int output )
+    public void setBundledOutput( ComputerSide side, int output )
     {
+        int index = side.ordinal();
         synchronized( internalOutput )
         {
-            if( internalBundledOutput[side] != output )
+            if( internalBundledOutput[index] != output )
             {
-                internalBundledOutput[side] = output;
+                internalBundledOutput[index] = output;
                 internalOutputChanged = true;
             }
         }
     }
 
     @Override
-    public int getBundledOutput( int side )
+    public int getBundledOutput( ComputerSide side )
     {
         synchronized( internalOutput )
         {
-            return computer.isOn() ? internalBundledOutput[side] : 0;
+            return computer.isOn() ? internalBundledOutput[side.ordinal()] : 0;
         }
     }
 
-    public int getExternalRedstoneOutput( int side )
+    public int getExternalRedstoneOutput( ComputerSide side )
     {
-        return computer.isOn() ? externalOutput[side] : 0;
+        return computer.isOn() ? externalOutput[side.ordinal()] : 0;
     }
 
-    public int getExternalBundledRedstoneOutput( int side )
+    public int getExternalBundledRedstoneOutput( ComputerSide side )
     {
-        return computer.isOn() ? externalBundledOutput[side] : 0;
+        return computer.isOn() ? externalBundledOutput[side.ordinal()] : 0;
     }
 
-    public void setRedstoneInput( int side, int level )
+    public void setRedstoneInput( ComputerSide side, int level )
     {
-        if( input[side] != level )
+        int index = side.ordinal();
+        if( input[index] != level )
         {
-            input[side] = level;
+            input[index] = level;
             inputChanged = true;
         }
     }
 
-    public void setBundledRedstoneInput( int side, int combination )
+    public void setBundledRedstoneInput( ComputerSide side, int combination )
     {
-        if( bundledInput[side] != combination )
+        int index = side.ordinal();
+        if( bundledInput[index] != combination )
         {
-            bundledInput[side] = combination;
+            bundledInput[index] = combination;
             inputChanged = true;
         }
     }
@@ -214,14 +219,14 @@ public final class Environment implements IAPIEnvironment
      */
     boolean updateOutput()
     {
-        // Set outputchanged if the internal redstone has changed
+        // Mark output as changed if the internal redstone has changed
         synchronized( internalOutput )
         {
             if( !internalOutputChanged ) return false;
 
             boolean changed = false;
 
-            for( int i = 0; i < SIDE_COUNT; i++ )
+            for( int i = 0; i < ComputerSide.COUNT; i++ )
             {
                 if( externalOutput[i] != internalOutput[i] )
                 {
@@ -254,24 +259,25 @@ public final class Environment implements IAPIEnvironment
     }
 
     @Override
-    public IPeripheral getPeripheral( int side )
+    public IPeripheral getPeripheral( ComputerSide side )
     {
         synchronized( peripherals )
         {
-            return peripherals[side];
+            return peripherals[side.ordinal()];
         }
     }
 
-    public void setPeripheral( int side, IPeripheral peripheral )
+    public void setPeripheral( ComputerSide side, IPeripheral peripheral )
     {
         synchronized( peripherals )
         {
-            IPeripheral existing = peripherals[side];
+            int index = side.ordinal();
+            IPeripheral existing = peripherals[index];
             if( (existing == null && peripheral != null) ||
                 (existing != null && peripheral == null) ||
                 (existing != null && !existing.equals( peripheral )) )
             {
-                peripherals[side] = peripheral;
+                peripherals[index] = peripheral;
                 if( peripheralListener != null ) peripheralListener.onPeripheralChanged( side, peripheral );
             }
         }