Fix finding inventories below y=0.

Thankfully, the surface level of redstone ready flat worlds is now below
y=0 or, I wouldn't have noticed.

I reformatted some things to keep the diffs down against CC-Tweaked.
It might be nicer to make this return an ItemStorage as most
places we grab the Container and immediately wrap it.

.gitpod.yml

@@ -1,5 +1,5 @@
 image:
-  file: .gitpod.Dockerfile
+  file: config/gitpod/Dockerfile
 
 ports:
   - port: 25565
@@ -7,12 +7,14 @@ ports:
 
 vscode:
   extensions:
+    - eamodio.gitlens
+    - github.vscode-pull-request-github
     - ms-azuretools.vscode-docker
     - redhat.java
     - richardwillis.vscode-gradle
     - vscjava.vscode-java-debug
     - vscode.github
 
-
 tasks:
-  - init: ./gradlew
+  - name: Setup pre-commit hool
+    init: pre-commit install --config config/pre-commit/config.yml --allow-missing-config

build.gradle

@@ -7,7 +7,7 @@ plugins {
     id 'fabric-loom' version '0.10-SNAPSHOT'
 }
 
-def javaVersion = JavaLanguageVersion.of(16)
+def javaVersion = JavaLanguageVersion.of(17)
 java {
     toolchain {
         languageVersion = javaVersion
@@ -83,8 +83,8 @@ dependencies {
     include 'com.electronwill.night-config:toml:3.6.3'
     include "me.shedaniel.cloth:cloth-config-fabric:${cloth_config_version}"
 
-    modRuntimeOnly "me.shedaniel:RoughlyEnoughItems-api-fabric:6.0.254-alpha"
-    modRuntimeOnly "me.shedaniel:RoughlyEnoughItems-fabric:6.0.254-alpha"
+    //modRuntimeOnly "me.shedaniel:RoughlyEnoughItems-api-fabric:6.0.254-alpha"
+    //modRuntimeOnly "me.shedaniel:RoughlyEnoughItems-fabric:6.0.254-alpha"
 
     testImplementation 'org.junit.jupiter:junit-jupiter-api:5.7.0'
     testImplementation 'org.junit.jupiter:junit-jupiter-params:5.7.0'
@@ -93,7 +93,7 @@ dependencies {
     testImplementation 'org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.5.21'
     testImplementation 'org.jetbrains.kotlinx:kotlinx-coroutines-core:1.5.1'
 
-    cctJavadoc 'cc.tweaked:cct-javadoc:1.4.1'
+    cctJavadoc 'cc.tweaked:cct-javadoc:1.4.2'
 }
 
 processResources {

doc/events/redstone.md

@@ -2,7 +2,7 @@
 module: [kind=event] redstone
 ---
 
-The @{redstone} event is fired whenever any redstone inputs on the computer change.
+The @{event!redstone} event is fired whenever any redstone inputs on the computer change.
 
 ## Example
 Prints a message when a redstone input changes:

gradle.properties

@@ -2,14 +2,13 @@
 org.gradle.jvmargs=-Xmx1G
 
 # Mod properties
-mod_version=1.97.2
+mod_version=1.99.1
 
 # Minecraft properties
-mc_version=1.17.1
-fabric_api_version=0.40.1+1.17
-fabric_loader_version=0.12.0
+mc_version=1.18.1
+fabric_api_version=0.44.0+1.18
+fabric_loader_version=0.12.11
 
 cloth_api_version=2.0.54
-cloth_config_version=5.0.34
-jankson_version=1.2.0
-modmenu_version=2.0.2
+cloth_config_version=6.0.42
+modmenu_version=3.0.0

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

@@ -3,12 +3,11 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft;
 
 import dan200.computercraft.core.apis.http.options.Action;
 import dan200.computercraft.core.apis.http.options.AddressRule;
-import dan200.computercraft.shared.ComputerCraftRegistry.ModBlocks;
+import dan200.computercraft.shared.Registry.ModBlocks;
 import dan200.computercraft.shared.common.ColourableRecipe;
 import dan200.computercraft.shared.computer.core.ClientComputerRegistry;
 import dan200.computercraft.shared.computer.core.ServerComputerRegistry;
@@ -37,24 +36,20 @@ import net.minecraft.world.item.ItemStack;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
-import java.util.Arrays;
-import java.util.Collections;
 import java.util.List;
 import java.util.concurrent.TimeUnit;
 
-import static dan200.computercraft.shared.ComputerCraftRegistry.init;
+import static dan200.computercraft.shared.Registry.init;
 
 public final class ComputerCraft implements ModInitializer
 {
     public static final String MOD_ID = "computercraft";
 
-    // Configuration fields
     public static int computerSpaceLimit = 1000 * 1000;
     public static int floppySpaceLimit = 125 * 1000;
     public static int maximumFilesOpen = 128;
     public static boolean disableLua51Features = false;
     public static String defaultComputerSettings = "";
-    public static boolean debugEnable = true;
     public static boolean logComputerErrors = true;
     public static boolean commandRequireCreative = true;
 
@@ -64,10 +59,11 @@ public final class ComputerCraft implements ModInitializer
 
     public static boolean httpEnabled = true;
     public static boolean httpWebsocketEnabled = true;
-    public static List<AddressRule> httpRules = Collections.unmodifiableList( Arrays.asList(
+    public static List<AddressRule> httpRules = List.of(
         AddressRule.parse( "$private", null, Action.DENY.toPartial() ),
         AddressRule.parse( "*", null, Action.ALLOW.toPartial() )
-    ) );
+    );
+
     public static int httpMaxRequests = 16;
     public static int httpMaxWebsockets = 4;
     public static int httpDownloadBandwidth = 32 * 1024 * 1024;
@@ -80,7 +76,6 @@ public final class ComputerCraft implements ModInitializer
     public static int modemHighAltitudeRangeDuringStorm = 384;
     public static int maxNotesPerTick = 8;
     public static MonitorRenderer monitorRenderer = MonitorRenderer.BEST;
-    public static double monitorDistanceSq = 4096;
     public static int monitorDistance = 65;
     public static long monitorBandwidth = 1_000_000;
 
@@ -98,6 +93,7 @@ public final class ComputerCraft implements ModInitializer
 
     public static int pocketTermWidth = 26;
     public static int pocketTermHeight = 20;
+
     public static int monitorWidth = 8;
     public static int monitorHeight = 6;
 

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

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft;
 
 import dan200.computercraft.api.ComputerCraftAPI.IComputerCraftAPI;
@@ -35,7 +34,6 @@ import net.fabricmc.loader.api.FabricLoader;
 import net.minecraft.core.BlockPos;
 import net.minecraft.core.Direction;
 import net.minecraft.resources.ResourceLocation;
-import net.minecraft.server.MinecraftServer;
 import net.minecraft.server.packs.resources.ReloadableResourceManager;
 import net.minecraft.world.level.BlockGetter;
 import net.minecraft.world.level.Level;
@@ -59,36 +57,24 @@ public final class ComputerCraftAPIImpl implements IComputerCraftAPI
 
     public static InputStream getResourceFile( String domain, String subPath )
     {
-        MinecraftServer server = GameInstanceUtils.getServer();
-        if( server != null )
+        ReloadableResourceManager manager = (ReloadableResourceManager) ((MinecraftServerAccess) GameInstanceUtils.getServer()).callGetResourceManager();
+        try
         {
-            ReloadableResourceManager manager = (ReloadableResourceManager) ((MinecraftServerAccess) server).callGetResourceManager();
-            try
-            {
-                return manager.getResource( new ResourceLocation( domain, subPath ) )
-                    .getInputStream();
-            }
-            catch( IOException ignored )
-            {
-                return null;
-            }
+            return manager.getResource( new ResourceLocation( domain, subPath ) ).getInputStream();
+        }
+        catch( IOException ignored )
+        {
+            return null;
         }
-        return null;
     }
 
     @Nonnull
     @Override
     public String getInstalledVersion()
     {
-        if( version != null )
-        {
-            return version;
-        }
-        return version = FabricLoader.getInstance()
-            .getModContainer( ComputerCraft.MOD_ID )
-            .map( x -> x.getMetadata()
-                .getVersion()
-                .toString() )
+        if( version != null ) return version;
+        return version = FabricLoader.getInstance().getModContainer( ComputerCraft.MOD_ID )
+            .map( x -> x.getMetadata().getVersion().toString() )
             .orElse( "unknown" );
     }
 
@@ -114,14 +100,9 @@ public final class ComputerCraftAPIImpl implements IComputerCraftAPI
     @Override
     public IMount createResourceMount( @Nonnull String domain, @Nonnull String subPath )
     {
-        MinecraftServer server = GameInstanceUtils.getServer();
-        if( server != null )
-        {
-            ReloadableResourceManager manager = (ReloadableResourceManager) ((MinecraftServerAccess) server).callGetResourceManager();
-            ResourceMount mount = ResourceMount.get( domain, subPath, manager );
-            return mount.exists( "" ) ? mount : null;
-        }
-        return null;
+        ReloadableResourceManager manager = (ReloadableResourceManager) ((MinecraftServerAccess) GameInstanceUtils.getServer()).callGetResourceManager();
+        ResourceMount mount = ResourceMount.get( domain, subPath, manager );
+        return mount.exists( "" ) ? mount : null;
     }
 
     @Override
@@ -130,12 +111,24 @@ public final class ComputerCraftAPIImpl implements IComputerCraftAPI
         Peripherals.register( provider );
     }
 
+    @Override
+    public void registerGenericSource( @Nonnull GenericSource source )
+    {
+        GenericMethod.register( source );
+    }
+
     @Override
     public void registerTurtleUpgrade( @Nonnull ITurtleUpgrade upgrade )
     {
         TurtleUpgrades.register( upgrade );
     }
 
+    @Override
+    public void registerPocketUpgrade( @Nonnull IPocketUpgrade upgrade )
+    {
+        PocketUpgrades.register( upgrade );
+    }
+
     @Override
     public void registerBundledRedstoneProvider( @Nonnull IBundledRedstoneProvider provider )
     {
@@ -154,18 +147,6 @@ public final class ComputerCraftAPIImpl implements IComputerCraftAPI
         MediaProviders.register( provider );
     }
 
-    @Override
-    public void registerPocketUpgrade( @Nonnull IPocketUpgrade upgrade )
-    {
-        PocketUpgrades.register( upgrade );
-    }
-
-    @Override
-    public void registerGenericSource( @Nonnull GenericSource source )
-    {
-        GenericMethod.register( source );
-    }
-
     @Nonnull
     @Override
     public IPacketNetwork getWirelessNetwork()

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

@@ -36,19 +36,14 @@ import javax.annotation.Nullable;
  */
 public final class ComputerCraftAPI
 {
+    public static final String MOD_ID = "computercraft";
+
     @Nonnull
     public static String getInstalledVersion()
     {
         return getInstance().getInstalledVersion();
     }
 
-    @Nonnull
-    @Deprecated
-    public static String getAPIVersion()
-    {
-        return getInstalledVersion();
-    }
-
     /**
      * Creates a numbered directory in a subfolder of the save directory for a given world, and returns that number.
      *
@@ -139,9 +134,9 @@ public final class ComputerCraftAPI
     }
 
     /**
-     * Registers a new turtle turtle for use in ComputerCraft. After calling this,
-     * users should be able to craft Turtles with your new turtle. It is recommended to call
-     * this during the load() method of your mod.
+     * Registers a new turtle upgrade for use in ComputerCraft. After calling this,
+     * users should be able to craft Turtles with your upgrade's ItemStack. It is
+     * recommended to call this during the load() method of your mod.
      *
      * @param upgrade The turtle upgrade to register.
      * @see ITurtleUpgrade
@@ -151,6 +146,19 @@ public final class ComputerCraftAPI
         getInstance().registerTurtleUpgrade( upgrade );
     }
 
+    /**
+     * Registers a new pocket upgrade for use in ComputerCraft. After calling this,
+     * users should be able to craft pocket computers with your upgrade's ItemStack. It is
+     * recommended to call this during the load() method of your mod.
+     *
+     * @param upgrade The pocket upgrade to register.
+     * @see IPocketUpgrade
+     */
+    public static void registerPocketUpgrade( @Nonnull IPocketUpgrade upgrade )
+    {
+        getInstance().registerPocketUpgrade( upgrade );
+    }
+
     /**
      * Registers a bundled redstone provider to provide bundled redstone output for blocks.
      *
@@ -188,11 +196,6 @@ public final class ComputerCraftAPI
         getInstance().registerMediaProvider( provider );
     }
 
-    public static void registerPocketUpgrade( @Nonnull IPocketUpgrade upgrade )
-    {
-        getInstance().registerPocketUpgrade( upgrade );
-    }
-
     /**
      * Attempt to get the game-wide wireless network.
      *
@@ -273,14 +276,13 @@ public final class ComputerCraftAPI
 
         void registerTurtleUpgrade( @Nonnull ITurtleUpgrade upgrade );
 
+        void registerPocketUpgrade( @Nonnull IPocketUpgrade upgrade );
+
         void registerBundledRedstoneProvider( @Nonnull IBundledRedstoneProvider provider );
 
         int getBundledRedstoneOutput( @Nonnull Level world, @Nonnull BlockPos pos, @Nonnull Direction side );
 
         void registerMediaProvider( @Nonnull IMediaProvider provider );
-
-        void registerPocketUpgrade( @Nonnull IPocketUpgrade upgrade );
-
         @Nonnull
         IPacketNetwork getWirelessNetwork();
 

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

@@ -0,0 +1,65 @@
+/*
+ * This file is part of the public ComputerCraft API - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2021. 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;
+
+import dan200.computercraft.ComputerCraft;
+import net.fabricmc.fabric.api.tag.TagFactory;
+import net.minecraft.resources.ResourceLocation;
+import net.minecraft.tags.Tag;
+import net.minecraft.world.item.Item;
+import net.minecraft.world.level.block.Block;
+
+/**
+ * Tags provided by ComputerCraft.
+ */
+public class ComputerCraftTags
+{
+    public static class Items
+    {
+        public static final Tag.Named<Item> COMPUTER = make( "computer" );
+        public static final Tag.Named<Item> TURTLE = make( "turtle" );
+        public static final Tag.Named<Item> WIRED_MODEM = make( "wired_modem" );
+        public static final Tag.Named<Item> MONITOR = make( "monitor" );
+
+        private static Tag.Named<Item> make( String name )
+        {
+            return TagFactory.ITEM.create( new ResourceLocation( ComputerCraft.MOD_ID, name ) );
+        }
+    }
+
+    public static class Blocks
+    {
+        public static final Tag.Named<Block> COMPUTER = make( "computer" );
+        public static final Tag.Named<Block> TURTLE = make( "turtle" );
+        public static final Tag.Named<Block> WIRED_MODEM = make( "wired_modem" );
+        public static final Tag.Named<Block> MONITOR = make( "monitor" );
+
+        /**
+         * Blocks which can be broken by any turtle tool.
+         */
+        public static final Tag.Named<Block> TURTLE_ALWAYS_BREAKABLE = make( "turtle_always_breakable" );
+
+        /**
+         * Blocks which can be broken by the default shovel tool.
+         */
+        public static final Tag.Named<Block> TURTLE_SHOVEL_BREAKABLE = make( "turtle_shovel_harvestable" );
+
+        /**
+         * Blocks which can be broken with the default sword tool.
+         */
+        public static final Tag.Named<Block> TURTLE_SWORD_BREAKABLE = make( "turtle_sword_harvestable" );
+
+        /**
+         * Blocks which can be broken with the default hoe tool.
+         */
+        public static final Tag.Named<Block> TURTLE_HOE_BREAKABLE = make( "turtle_hoe_harvestable" );
+
+        private static Tag.Named<Block> make( String name )
+        {
+            return TagFactory.BLOCK.create( new ResourceLocation( ComputerCraft.MOD_ID, name ) );
+        }
+    }
+}

src/main/java/dan200/computercraft/api/client/TransformedModel.java

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. 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.client;
 
 import com.mojang.blaze3d.vertex.PoseStack;

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

@@ -183,6 +183,24 @@ public interface IArguments
         return (Map<?, ?>) value;
     }
 
+    /**
+     * Get an argument as a table in an unsafe manner.
+     *
+     * Classes implementing this interface may choose to implement a more optimised version which does not copy the
+     * table, instead returning a wrapper version, making it more efficient. However, the caller must guarantee that
+     * they do not access off the computer thread (and so should not be used with main-thread functions) or once the
+     * function call has finished (for instance, in callbacks).
+     *
+     * @param index The argument number.
+     * @return The argument's value.
+     * @throws LuaException If the value is not a table.
+     */
+    @Nonnull
+    default LuaTable<?, ?> getTableUnsafe( int index ) throws LuaException
+    {
+        return new ObjectLuaTable( getTable( index ) );
+    }
+
     /**
      * Get an argument as a double.
      *
@@ -314,6 +332,27 @@ public interface IArguments
         return Optional.of( (Map<?, ?>) value );
     }
 
+    /**
+     * Get an argument as a table in an unsafe manner.
+     *
+     * Classes implementing this interface may choose to implement a more optimised version which does not copy the
+     * table, instead returning a wrapper version, making it more efficient. However, the caller must guarantee that
+     * they do not access off the computer thread (and so should not be used with main-thread functions) or once the
+     * function call has finished (for instance, in callbacks).
+     *
+     * @param index The argument number.
+     * @return The argument's value, or {@link Optional#empty()} if not present.
+     * @throws LuaException If the value is not a table.
+     */
+    @Nonnull
+    default Optional<LuaTable<?, ?>> optTableUnsafe( int index ) throws LuaException
+    {
+        Object value = get( index );
+        if( value == null ) return Optional.empty();
+        if( !(value instanceof Map) ) throw LuaValues.badArgumentOf( index, "map", value );
+        return Optional.of( new ObjectLuaTable( (Map<?, ?>) value ) );
+    }
+
     /**
      * Get an argument as a double.
      *
@@ -404,4 +443,13 @@ public interface IArguments
     {
         return optTable( index ).orElse( def );
     }
+
+    /**
+     * This is called when the current function finishes, before any main thread tasks have run.
+     *
+     * Called when the current function returns, and so some values are no longer guaranteed to be safe to access.
+     */
+    default void releaseImmediate()
+    {
+    }
 }

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

@@ -51,8 +51,17 @@ public @interface LuaFunction
      * Run this function on the main server thread. This should be specified for any method which interacts with
      * Minecraft in a thread-unsafe manner.
      *
-     * @return Whether this functi
+     * @return Whether this function should be run on the main thread.
      * @see ILuaContext#issueMainThreadTask(ILuaTask)
      */
     boolean mainThread() default false;
+
+    /**
+     * Allow using "unsafe" arguments, such {@link IArguments#getTableUnsafe(int)}.
+     *
+     * This is incompatible with {@link #mainThread()}.
+     *
+     * @return Whether this function supports unsafe arguments.
+     */
+    boolean unsafe() default false;
 }

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

@@ -0,0 +1,114 @@
+/*
+ * This file is part of the public ComputerCraft API - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2021. 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.lua;
+
+import org.jetbrains.annotations.Nullable;
+
+import javax.annotation.Nonnull;
+import java.util.Map;
+
+import static dan200.computercraft.api.lua.LuaValues.*;
+
+public interface LuaTable<K, V> extends Map<K, V>
+{
+    /**
+     * Compute the length of the array part of this table.
+     *
+     * @return This table's length.
+     */
+    default int length()
+    {
+        int size = 0;
+        while( containsKey( (double) (size + 1) ) ) size++;
+        return size;
+    }
+
+    /**
+     * Get an array entry as an integer.
+     *
+     * @param index The index in the table, starting at 1.
+     * @return The table's value.
+     * @throws LuaException If the value is not an integer.
+     */
+    default long getLong( int index ) throws LuaException
+    {
+        Object value = get( (double) index );
+        if( !(value instanceof Number) ) throw badTableItem( index, "number", getType( value ) );
+
+        Number number = (Number) value;
+        double asDouble = number.doubleValue();
+        if( !Double.isFinite( asDouble ) ) throw badTableItem( index, "number", getNumericType( asDouble ) );
+        return number.longValue();
+    }
+
+    /**
+     * Get a table entry as an integer.
+     *
+     * @param key The name of the field in the table.
+     * @return The table's value.
+     * @throws LuaException If the value is not an integer.
+     */
+    default long getLong( String key ) throws LuaException
+    {
+        Object value = get( key );
+        if( !(value instanceof Number) ) throw badField( key, "number", getType( value ) );
+
+        Number number = (Number) value;
+        double asDouble = number.doubleValue();
+        if( !Double.isFinite( asDouble ) ) throw badField( key, "number", getNumericType( asDouble ) );
+        return number.longValue();
+    }
+
+    /**
+     * Get an array entry as an integer.
+     *
+     * @param index The index in the table, starting at 1.
+     * @return The table's value.
+     * @throws LuaException If the value is not an integer.
+     */
+    default int getInt( int index ) throws LuaException
+    {
+        return (int) getLong( index );
+    }
+
+    /**
+     * Get a table entry as an integer.
+     *
+     * @param key The name of the field in the table.
+     * @return The table's value.
+     * @throws LuaException If the value is not an integer.
+     */
+    default int getInt( String key ) throws LuaException
+    {
+        return (int) getLong( key );
+    }
+
+
+    @Nullable
+    @Override
+    default V put( K o, V o2 )
+    {
+        throw new UnsupportedOperationException( "Cannot modify LuaTable" );
+    }
+
+    @Override
+    default V remove( Object o )
+    {
+        throw new UnsupportedOperationException( "Cannot modify LuaTable" );
+    }
+
+    @Override
+    default void putAll( @Nonnull Map<? extends K, ? extends V> map )
+    {
+        throw new UnsupportedOperationException( "Cannot modify LuaTable" );
+    }
+
+    @Override
+    default void clear()
+    {
+        throw new UnsupportedOperationException( "Cannot modify LuaTable" );
+    }
+}

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

@@ -102,6 +102,34 @@ public final class LuaValues
         return new LuaException( "bad argument #" + (index + 1) + " (" + expected + " expected, got " + actual + ")" );
     }
 
+    /**
+     * Construct a table item exception, from an expected and actual type.
+     *
+     * @param index    The index into the table, starting from 1.
+     * @param expected The expected type for this table item.
+     * @param actual   The provided type for this table item.
+     * @return The constructed exception, which should be thrown immediately.
+     */
+    @Nonnull
+    public static LuaException badTableItem( int index, @Nonnull String expected, @Nonnull String actual )
+    {
+        return new LuaException( "table item #" + index + " is not " + expected + " (got " + actual + ")" );
+    }
+
+    /**
+     * Construct a field exception, from an expected and actual type.
+     *
+     * @param key      The name of the field.
+     * @param expected The expected type for this table item.
+     * @param actual   The provided type for this table item.
+     * @return The constructed exception, which should be thrown immediately.
+     */
+    @Nonnull
+    public static LuaException badField( String key, @Nonnull String expected, @Nonnull String actual )
+    {
+        return new LuaException( "field " + key + " is not " + expected + " (got " + actual + ")" );
+    }
+
     /**
      * Ensure a numeric argument is finite (i.e. not infinite or {@link Double#NaN}.
      *

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

@@ -98,7 +98,10 @@ public final class MethodResult
     {
         Objects.requireNonNull( callback, "callback cannot be null" );
         return new MethodResult( new Object[] { filter }, results -> {
-            if( results.length >= 1 && results[0].equals( "terminate" ) ) throw new LuaException( "Terminated", 0 );
+            if( results.length >= 1 && Objects.equals( results[0], "terminate" ) )
+            {
+                throw new LuaException( "Terminated", 0 );
+            }
             return callback.resume( results );
         } );
     }

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

@@ -5,10 +5,12 @@
  */
 package dan200.computercraft.api.lua;
 
+import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 import java.util.Arrays;
 import java.util.List;
 import java.util.Objects;
+import java.util.Optional;
 
 /**
  * An implementation of {@link IArguments} which wraps an array of {@link Object}.
@@ -16,6 +18,8 @@ import java.util.Objects;
 public final class ObjectArguments implements IArguments
 {
     private static final IArguments EMPTY = new ObjectArguments();
+
+    private boolean released = false;
     private final List<Object> args;
 
     @Deprecated
@@ -63,4 +67,34 @@ public final class ObjectArguments implements IArguments
     {
         return args.toArray();
     }
+
+    @Nonnull
+    @Override
+    public LuaTable<?, ?> getTableUnsafe( int index ) throws LuaException
+    {
+        if( released )
+        {
+            throw new IllegalStateException( "Cannot use getTableUnsafe after IArguments has been released" );
+        }
+
+        return IArguments.super.getTableUnsafe( index );
+    }
+
+    @Nonnull
+    @Override
+    public Optional<LuaTable<?, ?>> optTableUnsafe( int index ) throws LuaException
+    {
+        if( released )
+        {
+            throw new IllegalStateException( "Cannot use optTableUnsafe after IArguments has been released" );
+        }
+
+        return IArguments.super.optTableUnsafe( index );
+    }
+
+    @Override
+    public void releaseImmediate()
+    {
+        released = true;
+    }
 }

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

@@ -0,0 +1,73 @@
+/*
+ * This file is part of the public ComputerCraft API - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2021. 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.lua;
+
+import javax.annotation.Nonnull;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Map;
+import java.util.Set;
+
+public class ObjectLuaTable implements LuaTable<Object, Object>
+{
+    private final Map<Object, Object> map;
+
+    public ObjectLuaTable( Map<?, ?> map )
+    {
+        this.map = Collections.unmodifiableMap( map );
+    }
+
+    @Override
+    public int size()
+    {
+        return map.size();
+    }
+
+    @Override
+    public boolean isEmpty()
+    {
+        return map.isEmpty();
+    }
+
+    @Override
+    public boolean containsKey( Object o )
+    {
+        return map.containsKey( o );
+    }
+
+    @Override
+    public boolean containsValue( Object o )
+    {
+        return map.containsKey( o );
+    }
+
+    @Override
+    public Object get( Object o )
+    {
+        return map.get( o );
+    }
+
+    @Nonnull
+    @Override
+    public Set<Object> keySet()
+    {
+        return map.keySet();
+    }
+
+    @Nonnull
+    @Override
+    public Collection<Object> values()
+    {
+        return map.values();
+    }
+
+    @Nonnull
+    @Override
+    public Set<Entry<Object, Object>> entrySet()
+    {
+        return map.entrySet();
+    }
+}

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

@@ -9,6 +9,8 @@ import dan200.computercraft.api.lua.LuaFunction;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
+import java.util.Collections;
+import java.util.Set;
 
 /**
  * The interface that defines a peripheral.
@@ -30,6 +32,18 @@ public interface IPeripheral
     @Nonnull
     String getType();
 
+    /**
+     * Return additional types/traits associated with this object.
+     *
+     * @return A collection of additional object traits.
+     * @see PeripheralType#getAdditionalTypes()
+     */
+    @Nonnull
+    default Set<String> getAdditionalTypes()
+    {
+        return Collections.emptySet();
+    }
+
     /**
      * Is called when when a computer is attaching to the peripheral.
      *

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

@@ -6,9 +6,13 @@
 package dan200.computercraft.api.peripheral;
 
 import com.google.common.base.Strings;
+import com.google.common.collect.ImmutableSet;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Set;
 
 /**
  * The type of a {@link GenericPeripheral}.
@@ -18,13 +22,19 @@ import javax.annotation.Nullable;
  */
 public final class PeripheralType
 {
-    private static final PeripheralType UNTYPED = new PeripheralType( null );
+    private static final PeripheralType UNTYPED = new PeripheralType( null, Collections.emptySet() );
 
     private final String type;
+    private final Set<String> additionalTypes;
 
-    public PeripheralType( String type )
+    public PeripheralType( String type, Set<String> additionalTypes )
     {
         this.type = type;
+        this.additionalTypes = additionalTypes;
+        if( additionalTypes.contains( null ) )
+        {
+            throw new IllegalArgumentException( "All additional types must be non-null" );
+        }
     }
 
     /**
@@ -46,7 +56,55 @@ public final class PeripheralType
     public static PeripheralType ofType( @Nonnull String type )
     {
         if( Strings.isNullOrEmpty( type ) ) throw new IllegalArgumentException( "type cannot be null or empty" );
-        return new PeripheralType( type );
+        return new PeripheralType( type, Collections.emptySet() );
+    }
+
+    /**
+     * Create a new non-empty peripheral type with additional traits.
+     *
+     * @param type            The name of the type.
+     * @param additionalTypes Additional types, or "traits" of this peripheral. For instance, {@literal "inventory"}.
+     * @return The constructed peripheral type.
+     */
+    public static PeripheralType ofType( @Nonnull String type, Collection<String> additionalTypes )
+    {
+        if( Strings.isNullOrEmpty( type ) ) throw new IllegalArgumentException( "type cannot be null or empty" );
+        return new PeripheralType( type, ImmutableSet.copyOf( additionalTypes ) );
+    }
+
+    /**
+     * Create a new non-empty peripheral type with additional traits.
+     *
+     * @param type            The name of the type.
+     * @param additionalTypes Additional types, or "traits" of this peripheral. For instance, {@literal "inventory"}.
+     * @return The constructed peripheral type.
+     */
+    public static PeripheralType ofType( @Nonnull String type, @Nonnull String... additionalTypes )
+    {
+        if( Strings.isNullOrEmpty( type ) ) throw new IllegalArgumentException( "type cannot be null or empty" );
+        return new PeripheralType( type, ImmutableSet.copyOf( additionalTypes ) );
+    }
+
+    /**
+     * Create a new peripheral type with no primary type but additional traits.
+     *
+     * @param additionalTypes Additional types, or "traits" of this peripheral. For instance, {@literal "inventory"}.
+     * @return The constructed peripheral type.
+     */
+    public static PeripheralType ofAdditional( Collection<String> additionalTypes )
+    {
+        return new PeripheralType( null, ImmutableSet.copyOf( additionalTypes ) );
+    }
+
+    /**
+     * Create a new peripheral type with no primary type but additional traits.
+     *
+     * @param additionalTypes Additional types, or "traits" of this peripheral. For instance, {@literal "inventory"}.
+     * @return The constructed peripheral type.
+     */
+    public static PeripheralType ofAdditional( @Nonnull String... additionalTypes )
+    {
+        return new PeripheralType( null, ImmutableSet.copyOf( additionalTypes ) );
     }
 
     /**
@@ -59,4 +117,15 @@ public final class PeripheralType
     {
         return type;
     }
+
+    /**
+     * Get any additional types or "traits" of this peripheral. These effectively act as a standard set of interfaces
+     * a peripheral might have.
+     *
+     * @return All additional types.
+     */
+    public Set<String> getAdditionalTypes()
+    {
+        return additionalTypes;
+    }
 }

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

@@ -6,7 +6,7 @@
 package dan200.computercraft.api.pocket;
 
 import dan200.computercraft.api.ComputerCraftAPI;
-import dan200.computercraft.api.IUpgradeBase;
+import dan200.computercraft.api.upgrades.IUpgradeBase;
 import dan200.computercraft.api.peripheral.IPeripheral;
 import net.minecraft.world.level.Level;
 

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

@@ -3,18 +3,13 @@
  * Copyright Daniel Ratcliffe, 2011-2021. 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.turtle;
 
-import dan200.computercraft.shared.util.NonNullSupplier;
-import net.minecraft.Util;
+import dan200.computercraft.api.upgrades.IUpgradeBase;
 import net.minecraft.resources.ResourceLocation;
-import net.minecraft.world.item.Item;
 import net.minecraft.world.item.ItemStack;
-import net.minecraft.world.level.ItemLike;
 
 import javax.annotation.Nonnull;
-import java.util.function.Supplier;
 
 /**
  * A base class for {@link ITurtleUpgrade}s.
@@ -26,9 +21,9 @@ public abstract class AbstractTurtleUpgrade implements ITurtleUpgrade
     private final ResourceLocation id;
     private final TurtleUpgradeType type;
     private final String adjective;
-    private final NonNullSupplier<ItemStack> stack;
+    private final ItemStack stack;
 
-    protected AbstractTurtleUpgrade( ResourceLocation id, TurtleUpgradeType type, String adjective, NonNullSupplier<ItemStack> stack )
+    protected AbstractTurtleUpgrade( ResourceLocation id, TurtleUpgradeType type, String adjective, ItemStack stack )
     {
         this.id = id;
         this.type = type;
@@ -36,39 +31,9 @@ public abstract class AbstractTurtleUpgrade implements ITurtleUpgrade
         this.stack = stack;
     }
 
-    protected AbstractTurtleUpgrade( ResourceLocation id, TurtleUpgradeType type, NonNullSupplier<ItemStack> stack )
-    {
-        this( id, type, Util.makeDescriptionId( "upgrade", id ) + ".adjective", stack );
-    }
-
-    protected AbstractTurtleUpgrade( ResourceLocation id, TurtleUpgradeType type, String adjective, ItemStack stack )
-    {
-        this( id, type, adjective, () -> stack );
-    }
-
     protected AbstractTurtleUpgrade( ResourceLocation id, TurtleUpgradeType type, ItemStack stack )
     {
-        this( id, type, () -> stack );
-    }
-
-    protected AbstractTurtleUpgrade( ResourceLocation id, TurtleUpgradeType type, String adjective, ItemLike item )
-    {
-        this( id, type, adjective, new CachedStack( () -> item ) );
-    }
-
-    protected AbstractTurtleUpgrade( ResourceLocation id, TurtleUpgradeType type, ItemLike item )
-    {
-        this( id, type, new CachedStack( () -> item ) );
-    }
-
-    protected AbstractTurtleUpgrade( ResourceLocation id, TurtleUpgradeType type, String adjective, Supplier<? extends ItemLike> item )
-    {
-        this( id, type, adjective, new CachedStack( item ) );
-    }
-
-    protected AbstractTurtleUpgrade( ResourceLocation id, TurtleUpgradeType type, Supplier<? extends ItemLike> item )
-    {
-        this( id, type, new CachedStack( item ) );
+        this( id, type, IUpgradeBase.getDefaultAdjective( id ), stack );
     }
 
     @Nonnull
@@ -96,32 +61,6 @@ public abstract class AbstractTurtleUpgrade implements ITurtleUpgrade
     @Override
     public final ItemStack getCraftingItem()
     {
-        return stack.get();
-    }
-
-    /**
-     * A supplier which converts an item into an item stack.
-     *
-     * Constructing item stacks is somewhat expensive due to attaching capabilities. We cache it if given a consistent item.
-     */
-    private static final class CachedStack implements NonNullSupplier<ItemStack>
-    {
-        private final Supplier<? extends ItemLike> provider;
-        private Item item;
-        private ItemStack stack;
-
-        CachedStack( Supplier<? extends ItemLike> provider )
-        {
-            this.provider = provider;
-        }
-
-        @Nonnull
-        @Override
-        public ItemStack get()
-        {
-            Item item = provider.get().asItem();
-            if( item == this.item && stack != null ) return stack;
-            return stack = new ItemStack( this.item = item );
-        }
+        return stack;
     }
 }

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

@@ -253,7 +253,7 @@ public class FakePlayer extends ServerPlayer
     }
 
     @Override
-    public void trackChunk( ChunkPos chunkPos, Packet<?> packet, Packet<?> packet2 )
+    public void trackChunk( ChunkPos chunkPos, Packet<?> packet )
     {
     }
 

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

@@ -6,7 +6,7 @@
 package dan200.computercraft.api.turtle;
 
 import dan200.computercraft.api.ComputerCraftAPI;
-import dan200.computercraft.api.IUpgradeBase;
+import dan200.computercraft.api.upgrades.IUpgradeBase;
 import dan200.computercraft.api.client.TransformedModel;
 import dan200.computercraft.api.peripheral.IPeripheral;
 import net.fabricmc.api.EnvType;

src/main/java/dan200/computercraft/api/upgrades/IUpgradeBase.java

@@ -3,10 +3,11 @@
  * Copyright Daniel Ratcliffe, 2011-2021. 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;
+package dan200.computercraft.api.upgrades;
 
 import dan200.computercraft.api.pocket.IPocketUpgrade;
 import dan200.computercraft.api.turtle.ITurtleUpgrade;
+import net.minecraft.Util;
 import net.minecraft.nbt.CompoundTag;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.item.ItemStack;
@@ -81,4 +82,18 @@ public interface IUpgradeBase
         if( craftingShareTag == null ) return shareTag.isEmpty();
         return shareTag.equals( craftingShareTag );
     }
+
+    /**
+     * Get a suitable default unlocalised adjective for an upgrade ID. This converts "modid:some_upgrade" to
+     * "upgrade.modid.some_upgrade.adjective".
+     *
+     * @param id The upgrade ID.
+     * @return The  generated adjective.
+     * @see #getUnlocalisedAdjective()
+     */
+    @Nonnull
+    static String getDefaultAdjective( @Nonnull ResourceLocation id )
+    {
+        return Util.makeDescriptionId( "upgrade", id ) + ".adjective";
+    }
 }

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

@@ -3,11 +3,10 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.client;
 
 import dan200.computercraft.ComputerCraft;
-import dan200.computercraft.shared.ComputerCraftRegistry;
+import dan200.computercraft.shared.Registry;
 import dan200.computercraft.shared.common.IColouredItem;
 import dan200.computercraft.shared.media.items.ItemDisk;
 import dan200.computercraft.shared.media.items.ItemTreasureDisk;
@@ -34,6 +33,7 @@ import java.util.function.Consumer;
 public final class ClientRegistry
 {
     private static final String[] EXTRA_MODELS = new String[] {
+        // Turtle upgrades
         "turtle_modem_normal_off_left",
         "turtle_modem_normal_on_left",
         "turtle_modem_normal_off_right",
@@ -49,6 +49,7 @@ public final class ClientRegistry
         "turtle_speaker_upgrade_left",
         "turtle_speaker_upgrade_right",
 
+        // Turtle block renderer
         "turtle_colour",
         "turtle_elf_overlay",
     };
@@ -85,10 +86,10 @@ public final class ClientRegistry
     {
         ColorProviderRegistry.ITEM.register( ( stack, layer ) -> {
             return layer == 1 ? ((ItemDisk) stack.getItem()).getColour( stack ) : 0xFFFFFF;
-        }, ComputerCraftRegistry.ModItems.DISK );
+        }, Registry.ModItems.DISK );
 
         ColorProviderRegistry.ITEM.register( ( stack, layer ) -> layer == 1 ? ItemTreasureDisk.getColour( stack ) : 0xFFFFFF,
-            ComputerCraftRegistry.ModItems.TREASURE_DISK );
+            Registry.ModItems.TREASURE_DISK );
 
         ColorProviderRegistry.ITEM.register( ( stack, layer ) -> {
             switch( layer )
@@ -102,12 +103,12 @@ public final class ClientRegistry
                     int light = ItemPocketComputer.getLightState( stack );
                     return light == -1 ? Colour.BLACK.getHex() : light;
             }
-        }, ComputerCraftRegistry.ModItems.POCKET_COMPUTER_NORMAL, ComputerCraftRegistry.ModItems.POCKET_COMPUTER_ADVANCED );
+        }, Registry.ModItems.POCKET_COMPUTER_NORMAL, Registry.ModItems.POCKET_COMPUTER_ADVANCED );
 
         // Setup turtle colours
         ColorProviderRegistry.ITEM.register( ( stack, tintIndex ) -> tintIndex == 0 ? ((IColouredItem) stack.getItem()).getColour( stack ) : 0xFFFFFF,
-            ComputerCraftRegistry.ModBlocks.TURTLE_NORMAL,
-            ComputerCraftRegistry.ModBlocks.TURTLE_ADVANCED );
+            Registry.ModBlocks.TURTLE_NORMAL,
+            Registry.ModBlocks.TURTLE_ADVANCED );
     }
 
     private static BakedModel bake( ModelBakery loader, UnbakedModel model, ResourceLocation identifier )

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

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.client;
 
 import dan200.computercraft.fabric.mixin.ChatComponentAccess;
@@ -25,17 +24,19 @@ public class ClientTableFormatter implements TableFormatter
 {
     public static final ClientTableFormatter INSTANCE = new ClientTableFormatter();
 
-    private static Int2IntOpenHashMap lastHeights = new Int2IntOpenHashMap();
+    private static final Int2IntOpenHashMap lastHeights = new Int2IntOpenHashMap();
+
+    private static Font renderer()
+    {
+        return Minecraft.getInstance().font;
+    }
 
     @Override
     @Nullable
     public Component getPadding( Component component, int width )
     {
         int extraWidth = width - getWidth( component );
-        if( extraWidth <= 0 )
-        {
-            return null;
-        }
+        if( extraWidth <= 0 ) return null;
 
         Font renderer = renderer();
 
@@ -46,11 +47,6 @@ public class ClientTableFormatter implements TableFormatter
         return ChatHelpers.coloured( StringUtils.repeat( ' ', spaces ) + StringUtils.repeat( (char) 712, extra ), ChatFormatting.GRAY );
     }
 
-    private static Font renderer()
-    {
-        return Minecraft.getInstance().font;
-    }
-
     @Override
     public int getColumnPadding()
     {
@@ -71,7 +67,7 @@ public class ClientTableFormatter implements TableFormatter
 
         // TODO: Trim the text if it goes over the allowed length
         // int maxWidth = MathHelper.floor( chat.getChatWidth() / chat.getScale() );
-        // List<ITextProperties> list = RenderComponentsUtil.func_238505_a_( component, maxWidth, mc.fontRenderer );
+        // List<ITextProperties> list = RenderComponentsUtil.wrapComponents( component, maxWidth, mc.fontRenderer );
         // if( !list.isEmpty() ) chat.printChatMessageWithOptionalDeletion( list.get( 0 ), id );
         ((ChatComponentAccess) chat).callAddMessage( component, id );
     }
@@ -86,10 +82,7 @@ public class ClientTableFormatter implements TableFormatter
         int height = TableFormatter.super.display( table );
         lastHeights.put( table.getId(), height );
 
-        for( int i = height; i < lastHeight; i++ )
-        {
-            ((ChatComponentAccess) chat).callRemoveById( i + table.getId() );
-        }
+        for( int i = height; i < lastHeight; i++ ) ((ChatComponentAccess) chat).callRemoveById( i + table.getId() );
         return height;
     }
 }

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

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.client;
 
 import net.fabricmc.fabric.api.client.event.lifecycle.v1.ClientTickEvents;

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

@@ -8,6 +8,7 @@ package dan200.computercraft.client.gui;
 import com.mojang.blaze3d.vertex.PoseStack;
 import dan200.computercraft.ComputerCraft;
 import dan200.computercraft.client.gui.widgets.ComputerSidebar;
+import dan200.computercraft.client.gui.widgets.DynamicImageButton;
 import dan200.computercraft.client.gui.widgets.WidgetTerminal;
 import dan200.computercraft.shared.computer.core.ClientComputer;
 import dan200.computercraft.shared.computer.core.ComputerFamily;
@@ -36,7 +37,6 @@ import java.util.List;
 
 public abstract class ComputerScreenBase<T extends ContainerComputerBase> extends AbstractContainerScreen<T>
 {
-
     private static final Component OK = new TranslatableComponent( "gui.ok" );
     private static final Component CANCEL = new TranslatableComponent( "gui.cancel" );
     private static final Component OVERWRITE = new TranslatableComponent( "gui.computercraft.upload.overwrite_button" );
@@ -94,6 +94,7 @@ public abstract class ComputerScreenBase<T extends ContainerComputerBase> extend
         return super.keyPressed( key, scancode, modifiers );
     }
 
+
     @Override
     public final void render( @Nonnull PoseStack stack, int mouseX, int mouseY, float partialTicks )
     {
@@ -102,12 +103,24 @@ public abstract class ComputerScreenBase<T extends ContainerComputerBase> extend
         renderTooltip( stack, mouseX, mouseY );
     }
 
+    @Override
+    public boolean mouseClicked( double x, double y, int button )
+    {
+        boolean changed = super.mouseClicked( x, y, button );
+        // Clicking the terminate/shutdown button steals focus, which means then pressing "enter" will click the button
+        // again. Restore the focus to the terminal in these cases.
+        if( getFocused() instanceof DynamicImageButton ) setFocused( terminal );
+        return changed;
+    }
+
     @Override
     public final 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 );
+        return (getFocused() != null && getFocused().mouseDragged( x, y, button, deltaX, deltaY ))
+            || super.mouseDragged( x, y, button, deltaX, deltaY );
     }
 
+
     @Override
     protected void renderLabels( @Nonnull PoseStack transform, int mouseX, int mouseY )
     {
@@ -207,7 +220,7 @@ public abstract class ComputerScreenBase<T extends ContainerComputerBase> extend
 
     private void continueUpload()
     {
-        if( minecraft.screen instanceof OptionScreen ) ((OptionScreen) minecraft.screen).disable();
+        if( minecraft.screen instanceof OptionScreen screen ) screen.disable();
         NetworkHandler.sendToServer( new ContinueUploadMessage( computer.getInstanceID(), true ) );
     }
 
@@ -224,5 +237,4 @@ public abstract class ComputerScreenBase<T extends ContainerComputerBase> extend
             () -> minecraft.setScreen( this )
         );
     }
-
 }

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

@@ -3,19 +3,17 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.client.gui;
 
+import com.mojang.blaze3d.vertex.Tesselator;
 import com.mojang.blaze3d.vertex.VertexConsumer;
 import com.mojang.math.Matrix4f;
-import com.mojang.math.Transformation;
 import dan200.computercraft.client.FrameInfo;
 import dan200.computercraft.client.render.RenderTypes;
 import dan200.computercraft.core.terminal.Terminal;
 import dan200.computercraft.core.terminal.TextBuffer;
 import dan200.computercraft.shared.util.Colour;
 import dan200.computercraft.shared.util.Palette;
-import net.minecraft.client.Minecraft;
 import net.minecraft.client.renderer.MultiBufferSource;
 import net.minecraft.resources.ResourceLocation;
 
@@ -24,25 +22,138 @@ import javax.annotation.Nullable;
 
 import static dan200.computercraft.client.render.RenderTypes.FULL_BRIGHT_LIGHTMAP;
 
+/**
+ * Handles rendering fixed width text and computer terminals.
+ *
+ * This class has several modes of usage:
+ * <ul>
+ * <li>{@link #drawString}: Drawing basic text without a terminal (such as for printouts). Unlike the other methods,
+ * this accepts a lightmap coordinate as, unlike terminals, printed pages render fullbright.</li>
+ * <li>{@link #drawTerminalWithoutCursor}/{@link #drawCursor}: Draw a terminal without a cursor and then draw the cursor
+ * separately. This is used by the monitor renderer to render the terminal to a VBO and draw the cursor dynamically.
+ * </li>
+ * <li>{@link #drawTerminal}: Draw a terminal with a cursor. This is used by the various computer GUIs to render the
+ * whole term.</li>
+ * <li>{@link #drawBlocker}: When rendering a terminal using {@link RenderTypes#TERMINAL_WITHOUT_DEPTH} you need to
+ * render an additional "depth blocker" on top of the monitor.</li>
+ * </ul>
+ */
 public final class FixedWidthFontRenderer
 {
+    public static final ResourceLocation FONT = new ResourceLocation( "computercraft", "textures/gui/term_font.png" );
+
     public static final int FONT_HEIGHT = 9;
     public static final int FONT_WIDTH = 6;
     public static final float WIDTH = 256.0f;
+
     public static final float BACKGROUND_START = (WIDTH - 6.0f) / WIDTH;
     public static final float BACKGROUND_END = (WIDTH - 4.0f) / WIDTH;
-    private static final Matrix4f IDENTITY = Transformation.identity()
-        .getMatrix();
-    public static final ResourceLocation FONT = new ResourceLocation( "computercraft", "textures/gui/term_font.png" );
-
 
     private FixedWidthFontRenderer()
     {
     }
 
-    public static void drawString( @Nonnull Matrix4f transform, @Nonnull VertexConsumer renderer, float x, float y, @Nonnull TextBuffer text,
-                                   @Nonnull TextBuffer textColour, @Nullable TextBuffer backgroundColour, @Nonnull Palette palette, boolean greyscale,
-                                   float leftMarginSize, float rightMarginSize, int light )
+    public static float toGreyscale( double[] rgb )
+    {
+        return (float) ((rgb[0] + rgb[1] + rgb[2]) / 3);
+    }
+
+    public static int getColour( char c, Colour def )
+    {
+        return 15 - Terminal.getColour( c, def );
+    }
+
+    private static void drawChar( Matrix4f transform, VertexConsumer buffer, float x, float y, int index, float r, float g, float b, int light )
+    {
+        // Short circuit to avoid the common case - the texture should be blank here after all.
+        if( index == '\0' || index == ' ' ) return;
+
+        int column = index % 16;
+        int row = index / 16;
+
+        int xStart = 1 + column * (FONT_WIDTH + 2);
+        int yStart = 1 + row * (FONT_HEIGHT + 2);
+
+        buffer.vertex( transform, x, y, 0f ).color( r, g, b, 1.0f ).uv( xStart / WIDTH, yStart / WIDTH ).uv2( light ).endVertex();
+        buffer.vertex( transform, x, y + FONT_HEIGHT, 0f ).color( r, g, b, 1.0f ).uv( xStart / WIDTH, (yStart + FONT_HEIGHT) / WIDTH ).uv2( light ).endVertex();
+        buffer.vertex( transform, x + FONT_WIDTH, y, 0f ).color( r, g, b, 1.0f ).uv( (xStart + FONT_WIDTH) / WIDTH, yStart / WIDTH ).uv2( light ).endVertex();
+        buffer.vertex( transform, x + FONT_WIDTH, y, 0f ).color( r, g, b, 1.0f ).uv( (xStart + FONT_WIDTH) / WIDTH, yStart / WIDTH ).uv2( light ).endVertex();
+        buffer.vertex( transform, x, y + FONT_HEIGHT, 0f ).color( r, g, b, 1.0f ).uv( xStart / WIDTH, (yStart + FONT_HEIGHT) / WIDTH ).uv2( light ).endVertex();
+        buffer.vertex( transform, x + FONT_WIDTH, y + FONT_HEIGHT, 0f ).color( r, g, b, 1.0f ).uv( (xStart + FONT_WIDTH) / WIDTH, (yStart + FONT_HEIGHT) / WIDTH ).uv2( light ).endVertex();
+    }
+
+    private static void drawQuad( Matrix4f transform, VertexConsumer buffer, float x, float y, float width, float height, float r, float g, float b )
+    {
+        buffer.vertex( transform, x, y, 0 ).color( r, g, b, 1.0f ).uv( BACKGROUND_START, BACKGROUND_START ).endVertex();
+        buffer.vertex( transform, x, y + height, 0 ).color( r, g, b, 1.0f ).uv( BACKGROUND_START, BACKGROUND_END ).endVertex();
+        buffer.vertex( transform, x + width, y, 0 ).color( r, g, b, 1.0f ).uv( BACKGROUND_END, BACKGROUND_START ).endVertex();
+        buffer.vertex( transform, x + width, y, 0 ).color( r, g, b, 1.0f ).uv( BACKGROUND_END, BACKGROUND_START ).endVertex();
+        buffer.vertex( transform, x, y + height, 0 ).color( r, g, b, 1.0f ).uv( BACKGROUND_START, BACKGROUND_END ).endVertex();
+        buffer.vertex( transform, x + width, y + height, 0 ).color( r, g, b, 1.0f ).uv( BACKGROUND_END, BACKGROUND_END ).endVertex();
+    }
+
+    private static void drawQuad( Matrix4f transform, VertexConsumer buffer, float x, float y, float width, float height, Palette palette, boolean greyscale, char colourIndex )
+    {
+        double[] colour = palette.getColour( getColour( colourIndex, Colour.BLACK ) );
+        float r, g, b;
+        if( greyscale )
+        {
+            r = g = b = toGreyscale( colour );
+        }
+        else
+        {
+            r = (float) colour[0];
+            g = (float) colour[1];
+            b = (float) colour[2];
+        }
+
+        drawQuad( transform, buffer, x, y, width, height, r, g, b );
+    }
+
+    private static void drawBackground(
+        @Nonnull Matrix4f transform, @Nonnull VertexConsumer renderer, float x, float y,
+        @Nonnull TextBuffer backgroundColour, @Nonnull Palette palette, boolean greyscale,
+        float leftMarginSize, float rightMarginSize, float height
+    )
+    {
+        if( leftMarginSize > 0 )
+        {
+            drawQuad( transform, renderer, x - leftMarginSize, y, leftMarginSize, height, palette, greyscale, backgroundColour.charAt( 0 ) );
+        }
+
+        if( rightMarginSize > 0 )
+        {
+            drawQuad( transform, renderer, x + backgroundColour.length() * FONT_WIDTH, y, rightMarginSize, height, palette, greyscale, backgroundColour.charAt( backgroundColour.length() - 1 ) );
+        }
+
+        // Batch together runs of identical background cells.
+        int blockStart = 0;
+        char blockColour = '\0';
+        for( int i = 0; i < backgroundColour.length(); i++ )
+        {
+            char colourIndex = backgroundColour.charAt( i );
+            if( colourIndex == blockColour ) continue;
+
+            if( blockColour != '\0' )
+            {
+                drawQuad( transform, renderer, x + blockStart * FONT_WIDTH, y, FONT_WIDTH * (i - blockStart), height, palette, greyscale, blockColour );
+            }
+
+            blockColour = colourIndex;
+            blockStart = i;
+        }
+
+        if( blockColour != '\0' )
+        {
+            drawQuad( transform, renderer, x + blockStart * FONT_WIDTH, y, FONT_WIDTH * (backgroundColour.length() - blockStart), height, palette, greyscale, blockColour );
+        }
+    }
+
+    public static void drawString(
+        @Nonnull Matrix4f transform, @Nonnull VertexConsumer renderer, float x, float y,
+        @Nonnull TextBuffer text, @Nonnull TextBuffer textColour, @Nullable TextBuffer backgroundColour,
+        @Nonnull Palette palette, boolean greyscale, float leftMarginSize, float rightMarginSize, int light
+    )
     {
         if( backgroundColour != null )
         {
@@ -66,223 +177,49 @@ public final class FixedWidthFontRenderer
 
             // Draw char
             int index = text.charAt( i );
-            if( index > 255 )
-            {
-                index = '?';
-            }
+            if( index > 255 ) index = '?';
             drawChar( transform, renderer, x + i * FONT_WIDTH, y, index, r, g, b, light );
         }
 
     }
 
-    private static void drawBackground( @Nonnull Matrix4f transform, @Nonnull VertexConsumer renderer, float x, float y,
-                                        @Nonnull TextBuffer backgroundColour, @Nonnull Palette palette, boolean greyscale, float leftMarginSize,
-                                        float rightMarginSize, float height )
-    {
-        if( leftMarginSize > 0 )
-        {
-            drawQuad( transform, renderer, x - leftMarginSize, y, leftMarginSize, height, palette, greyscale, backgroundColour.charAt( 0 ) );
-        }
-
-        if( rightMarginSize > 0 )
-        {
-            drawQuad( transform,
-                renderer,
-                x + backgroundColour.length() * FONT_WIDTH,
-                y,
-                rightMarginSize,
-                height,
-                palette,
-                greyscale,
-                backgroundColour.charAt( backgroundColour.length() - 1 ) );
-        }
-
-        // Batch together runs of identical background cells.
-        int blockStart = 0;
-        char blockColour = '\0';
-        for( int i = 0; i < backgroundColour.length(); i++ )
-        {
-            char colourIndex = backgroundColour.charAt( i );
-            if( colourIndex == blockColour )
-            {
-                continue;
-            }
-
-            if( blockColour != '\0' )
-            {
-                drawQuad( transform, renderer, x + blockStart * FONT_WIDTH, y, FONT_WIDTH * (i - blockStart), height, palette, greyscale, blockColour );
-            }
-
-            blockColour = colourIndex;
-            blockStart = i;
-        }
-
-        if( blockColour != '\0' )
-        {
-            drawQuad( transform,
-                renderer,
-                x + blockStart * FONT_WIDTH,
-                y,
-                FONT_WIDTH * (backgroundColour.length() - blockStart),
-                height,
-                palette,
-                greyscale,
-                blockColour );
-        }
-    }
-
-    public static int getColour( char c, Colour def )
-    {
-        return 15 - Terminal.getColour( c, def );
-    }
-
-    public static float toGreyscale( double[] rgb )
-    {
-        return (float) ((rgb[0] + rgb[1] + rgb[2]) / 3);
-    }
-
-    private static void drawChar( Matrix4f transform, VertexConsumer buffer, float x, float y, int index, float r, float g, float b, int light )
-    {
-        // Short circuit to avoid the common case - the texture should be blank here after all.
-        if( index == '\0' || index == ' ' )
-        {
-            return;
-        }
-
-        int column = index % 16;
-        int row = index / 16;
-
-        int xStart = 1 + column * (FONT_WIDTH + 2);
-        int yStart = 1 + row * (FONT_HEIGHT + 2);
-
-        buffer.vertex( transform, x, y, 0f )
-            .color( r, g, b, 1.0f )
-            .uv( xStart / WIDTH, yStart / WIDTH )
-            .uv2( light )
-            .endVertex();
-        buffer.vertex( transform, x, y + FONT_HEIGHT, 0f )
-            .color( r, g, b, 1.0f )
-            .uv( xStart / WIDTH, (yStart + FONT_HEIGHT) / WIDTH )
-            .uv2( light )
-            .endVertex();
-        buffer.vertex( transform, x + FONT_WIDTH, y, 0f )
-            .color( r, g, b, 1.0f )
-            .uv( (xStart + FONT_WIDTH) / WIDTH, yStart / WIDTH )
-            .uv2( light )
-            .endVertex();
-        buffer.vertex( transform, x + FONT_WIDTH, y, 0f )
-            .color( r, g, b, 1.0f )
-            .uv( (xStart + FONT_WIDTH) / WIDTH, yStart / WIDTH )
-            .uv2( light )
-            .endVertex();
-        buffer.vertex( transform, x, y + FONT_HEIGHT, 0f )
-            .color( r, g, b, 1.0f )
-            .uv( xStart / WIDTH, (yStart + FONT_HEIGHT) / WIDTH )
-            .uv2( light )
-            .endVertex();
-        buffer.vertex( transform, x + FONT_WIDTH, y + FONT_HEIGHT, 0f )
-            .color( r, g, b, 1.0f )
-            .uv( (xStart + FONT_WIDTH) / WIDTH, (yStart + FONT_HEIGHT) / WIDTH )
-            .uv2( light )
-            .endVertex();
-    }
-
-    private static void drawQuad( Matrix4f transform, VertexConsumer buffer, float x, float y, float width, float height, Palette palette,
-                                  boolean greyscale, char colourIndex )
-    {
-        double[] colour = palette.getColour( getColour( colourIndex, Colour.BLACK ) );
-        float r, g, b;
-        if( greyscale )
-        {
-            r = g = b = toGreyscale( colour );
-        }
-        else
-        {
-            r = (float) colour[0];
-            g = (float) colour[1];
-            b = (float) colour[2];
-        }
-
-        drawQuad( transform, buffer, x, y, width, height, r, g, b );
-    }
-
-    private static void drawQuad( Matrix4f transform, VertexConsumer buffer, float x, float y, float width, float height, float r, float g, float b )
-    {
-        buffer.vertex( transform, x, y, 0 )
-            .color( r, g, b, 1.0f )
-            .uv( BACKGROUND_START, BACKGROUND_START )
-            .endVertex();
-        buffer.vertex( transform, x, y + height, 0 )
-            .color( r, g, b, 1.0f )
-            .uv( BACKGROUND_START, BACKGROUND_END )
-            .endVertex();
-        buffer.vertex( transform, x + width, y, 0 )
-            .color( r, g, b, 1.0f )
-            .uv( BACKGROUND_END, BACKGROUND_START )
-            .endVertex();
-        buffer.vertex( transform, x + width, y, 0 )
-            .color( r, g, b, 1.0f )
-            .uv( BACKGROUND_END, BACKGROUND_START )
-            .endVertex();
-        buffer.vertex( transform, x, y + height, 0 )
-            .color( r, g, b, 1.0f )
-            .uv( BACKGROUND_START, BACKGROUND_END )
-            .endVertex();
-        buffer.vertex( transform, x + width, y + height, 0 )
-            .color( r, g, b, 1.0f )
-            .uv( BACKGROUND_END, BACKGROUND_END )
-            .endVertex();
-    }
-
-    public static void drawTerminalWithoutCursor( @Nonnull Matrix4f transform, @Nonnull VertexConsumer buffer, float x, float y,
-                                                  @Nonnull Terminal terminal, boolean greyscale, float topMarginSize, float bottomMarginSize,
-                                                  float leftMarginSize, float rightMarginSize )
+    public static void drawTerminalWithoutCursor(
+        @Nonnull Matrix4f transform, @Nonnull VertexConsumer buffer, float x, float y,
+        @Nonnull Terminal terminal, boolean greyscale,
+        float topMarginSize, float bottomMarginSize, float leftMarginSize, float rightMarginSize
+    )
     {
         Palette palette = terminal.getPalette();
         int height = terminal.getHeight();
 
         // Top and bottom margins
-        drawBackground( transform,
-            buffer,
-            x,
-            y - topMarginSize,
-            terminal.getBackgroundColourLine( 0 ),
-            palette,
-            greyscale,
-            leftMarginSize,
-            rightMarginSize,
-            topMarginSize );
+        drawBackground(
+            transform, buffer, x, y - topMarginSize,
+            terminal.getBackgroundColourLine( 0 ), palette, greyscale,
+            leftMarginSize, rightMarginSize, topMarginSize
+        );
 
-        drawBackground( transform,
-            buffer,
-            x,
-            y + height * FONT_HEIGHT,
-            terminal.getBackgroundColourLine( height - 1 ),
-            palette,
-            greyscale,
-            leftMarginSize,
-            rightMarginSize,
-            bottomMarginSize );
+        drawBackground(
+            transform, buffer, x, y + height * FONT_HEIGHT,
+            terminal.getBackgroundColourLine( height - 1 ), palette, greyscale,
+            leftMarginSize, rightMarginSize, bottomMarginSize
+        );
 
         // The main text
         for( int i = 0; i < height; i++ )
         {
-            drawString( transform,
-                buffer,
-                x,
-                y + FixedWidthFontRenderer.FONT_HEIGHT * i,
-                terminal.getLine( i ),
-                terminal.getTextColourLine( i ),
-                terminal.getBackgroundColourLine( i ),
-                palette,
-                greyscale,
-                leftMarginSize,
-                rightMarginSize, FULL_BRIGHT_LIGHTMAP );
+            drawString(
+                transform, buffer, x, y + FixedWidthFontRenderer.FONT_HEIGHT * i,
+                terminal.getLine( i ), terminal.getTextColourLine( i ), terminal.getBackgroundColourLine( i ),
+                palette, greyscale, leftMarginSize, rightMarginSize, FULL_BRIGHT_LIGHTMAP
+            );
         }
     }
 
-    public static void drawCursor( @Nonnull Matrix4f transform, @Nonnull VertexConsumer buffer, float x, float y, @Nonnull Terminal terminal,
-                                   boolean greyscale )
+    public static void drawCursor(
+        @Nonnull Matrix4f transform, @Nonnull VertexConsumer buffer, float x, float y,
+        @Nonnull Terminal terminal, boolean greyscale
+    )
     {
         Palette palette = terminal.getPalette();
         int width = terminal.getWidth();
@@ -309,52 +246,40 @@ public final class FixedWidthFontRenderer
         }
     }
 
-    public static void drawTerminal( @Nonnull Matrix4f transform, @Nonnull VertexConsumer buffer, float x, float y, @Nonnull Terminal terminal,
-                                     boolean greyscale, float topMarginSize, float bottomMarginSize, float leftMarginSize, float rightMarginSize )
+    public static void drawTerminal(
+        @Nonnull Matrix4f transform, @Nonnull VertexConsumer buffer, float x, float y,
+        @Nonnull Terminal terminal, boolean greyscale,
+        float topMarginSize, float bottomMarginSize, float leftMarginSize, float rightMarginSize
+    )
     {
         drawTerminalWithoutCursor( transform, buffer, x, y, terminal, greyscale, topMarginSize, bottomMarginSize, leftMarginSize, rightMarginSize );
         drawCursor( transform, buffer, x, y, terminal, greyscale );
     }
 
-    public static void drawTerminal( @Nonnull Matrix4f transform, float x, float y, @Nonnull Terminal terminal, boolean greyscale, float topMarginSize,
-                                     float bottomMarginSize, float leftMarginSize, float rightMarginSize )
+    public static void drawTerminal(
+        @Nonnull Matrix4f transform, float x, float y, @Nonnull Terminal terminal, boolean greyscale,
+        float topMarginSize, float bottomMarginSize, float leftMarginSize, float rightMarginSize
+    )
     {
-        MultiBufferSource.BufferSource renderer = Minecraft.getInstance()
-            .renderBuffers()
-            .bufferSource();
+        MultiBufferSource.BufferSource renderer = MultiBufferSource.immediate( Tesselator.getInstance().getBuilder() );
         VertexConsumer buffer = renderer.getBuffer( RenderTypes.TERMINAL_WITH_DEPTH );
         drawTerminal( transform, buffer, x, y, terminal, greyscale, topMarginSize, bottomMarginSize, leftMarginSize, rightMarginSize );
         renderer.endBatch();
     }
 
-    public static void drawTerminal( float x, float y, @Nonnull Terminal terminal, boolean greyscale, float topMarginSize, float bottomMarginSize,
-                                     float leftMarginSize, float rightMarginSize )
-    {
-        drawTerminal( IDENTITY, x, y, terminal, greyscale, topMarginSize, bottomMarginSize, leftMarginSize, rightMarginSize );
-    }
-
-    public static void drawEmptyTerminal( float x, float y, float width, float height )
+    public static void drawEmptyTerminal( @Nonnull Matrix4f transform, @Nonnull MultiBufferSource renderer, float x, float y, float width, float height )
     {
         Colour colour = Colour.BLACK;
-        drawEmptyTerminal( IDENTITY, x, y, width, height );
+        drawQuad( transform, renderer.getBuffer( RenderTypes.TERMINAL_WITH_DEPTH ), x, y, width, height, colour.getR(), colour.getG(), colour.getB() );
     }
 
     public static void drawEmptyTerminal( @Nonnull Matrix4f transform, float x, float y, float width, float height )
     {
-        MultiBufferSource.BufferSource renderer = Minecraft.getInstance()
-            .renderBuffers()
-            .bufferSource();
+        MultiBufferSource.BufferSource renderer = MultiBufferSource.immediate( Tesselator.getInstance().getBuilder() );
         drawEmptyTerminal( transform, renderer, x, y, width, height );
         renderer.endBatch();
     }
 
-    public static void drawEmptyTerminal( @Nonnull Matrix4f transform, @Nonnull MultiBufferSource renderer, float x, float y, float width,
-                                          float height )
-    {
-        Colour colour = Colour.BLACK;
-        drawQuad( transform, renderer.getBuffer( RenderTypes.TERMINAL_WITH_DEPTH ), x, y, width, height, colour.getR(), colour.getG(), colour.getB() );
-    }
-
     public static void drawBlocker( @Nonnull Matrix4f transform, @Nonnull MultiBufferSource renderer, float x, float y, float width, float height )
     {
         Colour colour = Colour.BLACK;

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

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.client.gui;
 
 import com.mojang.blaze3d.vertex.PoseStack;
@@ -20,14 +19,15 @@ import net.minecraft.world.entity.player.Inventory;
 import javax.annotation.Nonnull;
 
 import static dan200.computercraft.client.render.ComputerBorderRenderer.BORDER;
-import static dan200.computercraft.client.render.ComputerBorderRenderer.getTexture;
 
 public final class GuiComputer<T extends ContainerComputerBase> extends ComputerScreenBase<T>
 {
     private final int termWidth;
     private final int termHeight;
 
-    private GuiComputer( T container, Inventory player, Component title, int termWidth, int termHeight )
+    private GuiComputer(
+        T container, Inventory player, Component title, int termWidth, int termHeight
+    )
     {
         super( container, player, title, BORDER );
         this.termWidth = termWidth;
@@ -37,19 +37,31 @@ public final class GuiComputer<T extends ContainerComputerBase> extends Computer
         imageHeight = WidgetTerminal.getHeight( termHeight ) + BORDER * 2;
     }
 
+    @Nonnull
     public static GuiComputer<ContainerComputerBase> create( ContainerComputerBase container, Inventory inventory, Component component )
     {
-        return new GuiComputer<>( container, inventory, component, ComputerCraft.computerTermWidth, ComputerCraft.computerTermHeight );
+        return new GuiComputer<>(
+            container, inventory, component,
+            ComputerCraft.computerTermWidth, ComputerCraft.computerTermHeight
+        );
     }
 
+    @Nonnull
     public static GuiComputer<ContainerComputerBase> createPocket( ContainerComputerBase container, Inventory inventory, Component component )
     {
-        return new GuiComputer<>( container, inventory, component, ComputerCraft.pocketTermWidth, ComputerCraft.pocketTermHeight );
+        return new GuiComputer<>(
+            container, inventory, component,
+            ComputerCraft.pocketTermWidth, ComputerCraft.pocketTermHeight
+        );
     }
 
+    @Nonnull
     public static GuiComputer<ContainerViewComputer> createView( ContainerViewComputer container, Inventory inventory, Component component )
     {
-        return new GuiComputer<>( container, inventory, component, container.getWidth(), container.getHeight() );
+        return new GuiComputer<>(
+            container, inventory, component,
+            container.getWidth(), container.getHeight()
+        );
     }
 
     @Override
@@ -63,9 +75,11 @@ public final class GuiComputer<T extends ContainerComputerBase> extends Computer
     @Override
     public void renderBg( @Nonnull PoseStack stack, float partialTicks, int mouseX, int mouseY )
     {
+        // Draw a border around the terminal
         ComputerBorderRenderer.render(
-            getTexture( family ), terminal.x, terminal.y, getBlitOffset(),
-            RenderTypes.FULL_BRIGHT_LIGHTMAP, terminal.getWidth(), terminal.getHeight() );
+            ComputerBorderRenderer.getTexture( family ), terminal.x, terminal.y, getBlitOffset(),
+            RenderTypes.FULL_BRIGHT_LIGHTMAP, terminal.getWidth(), terminal.getHeight()
+        );
         ComputerSidebar.renderBackground( stack, leftPos, topPos + sidebarYOffset );
     }
 }

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

@@ -3,14 +3,12 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.client.gui;
 
 import com.mojang.blaze3d.systems.RenderSystem;
 import com.mojang.blaze3d.vertex.PoseStack;
 import dan200.computercraft.shared.peripheral.diskdrive.ContainerDiskDrive;
 import net.minecraft.client.gui.screens.inventory.AbstractContainerScreen;
-import net.minecraft.client.renderer.GameRenderer;
 import net.minecraft.network.chat.Component;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.entity.player.Inventory;
@@ -26,6 +24,14 @@ public class GuiDiskDrive extends AbstractContainerScreen<ContainerDiskDrive>
         super( container, player, title );
     }
 
+    @Override
+    protected void renderBg( @Nonnull PoseStack transform, float partialTicks, int mouseX, int mouseY )
+    {
+        RenderSystem.setShaderColor( 1.0F, 1.0F, 1.0F, 1.0F );
+        RenderSystem.setShaderTexture( 0, BACKGROUND );
+        blit( transform, leftPos, topPos, 0, 0, imageWidth, imageHeight );
+    }
+
     @Override
     public void render( @Nonnull PoseStack transform, int mouseX, int mouseY, float partialTicks )
     {
@@ -33,13 +39,4 @@ public class GuiDiskDrive extends AbstractContainerScreen<ContainerDiskDrive>
         super.render( transform, mouseX, mouseY, partialTicks );
         renderTooltip( transform, mouseX, mouseY );
     }
-
-    @Override
-    protected void renderBg( @Nonnull PoseStack transform, float partialTicks, int mouseX, int mouseY )
-    {
-        RenderSystem.setShader( GameRenderer::getPositionTexShader );
-        RenderSystem.setShaderColor( 1.0F, 1.0F, 1.0F, 1.0F );
-        RenderSystem.setShaderTexture( 0, BACKGROUND );
-        blit( transform, leftPos, topPos, 0, 0, imageWidth, imageHeight );
-    }
 }

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

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.client.gui;
 
 import com.mojang.blaze3d.systems.RenderSystem;
@@ -25,14 +24,6 @@ public class GuiPrinter extends AbstractContainerScreen<ContainerPrinter>
         super( container, player, title );
     }
 
-    @Override
-    public void render( @Nonnull PoseStack stack, int mouseX, int mouseY, float partialTicks )
-    {
-        renderBackground( stack );
-        super.render( stack, mouseX, mouseY, partialTicks );
-        renderTooltip( stack, mouseX, mouseY );
-    }
-
     @Override
     protected void renderBg( @Nonnull PoseStack transform, float partialTicks, int mouseX, int mouseY )
     {
@@ -40,9 +31,14 @@ public class GuiPrinter extends AbstractContainerScreen<ContainerPrinter>
         RenderSystem.setShaderTexture( 0, BACKGROUND );
         blit( transform, leftPos, topPos, 0, 0, imageWidth, imageHeight );
 
-        if( getMenu().isPrinting() )
-        {
-            blit( transform, leftPos + 34, topPos + 21, 176, 0, 25, 45 );
-        }
+        if( getMenu().isPrinting() ) blit( transform, leftPos + 34, topPos + 21, 176, 0, 25, 45 );
+    }
+
+    @Override
+    public void render( @Nonnull PoseStack stack, int mouseX, int mouseY, float partialTicks )
+    {
+        renderBackground( stack );
+        super.render( stack, mouseX, mouseY, partialTicks );
+        renderTooltip( stack, mouseX, mouseY );
     }
 }

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

@@ -3,16 +3,15 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.client.gui;
 
 import com.mojang.blaze3d.systems.RenderSystem;
 import com.mojang.blaze3d.vertex.PoseStack;
+import com.mojang.blaze3d.vertex.Tesselator;
 import com.mojang.math.Matrix4f;
 import dan200.computercraft.core.terminal.TextBuffer;
 import dan200.computercraft.shared.common.ContainerHeldItem;
 import dan200.computercraft.shared.media.items.ItemPrintout;
-import net.minecraft.client.Minecraft;
 import net.minecraft.client.gui.screens.inventory.AbstractContainerScreen;
 import net.minecraft.client.renderer.MultiBufferSource;
 import net.minecraft.network.chat.Component;
@@ -40,54 +39,72 @@ public class GuiPrintout extends AbstractContainerScreen<ContainerHeldItem>
 
         String[] text = ItemPrintout.getText( container.getStack() );
         this.text = new TextBuffer[text.length];
-        for( int i = 0; i < this.text.length; i++ )
-        {
-            this.text[i] = new TextBuffer( text[i] );
-        }
+        for( int i = 0; i < this.text.length; i++ ) this.text[i] = new TextBuffer( text[i] );
 
         String[] colours = ItemPrintout.getColours( container.getStack() );
         this.colours = new TextBuffer[colours.length];
-        for( int i = 0; i < this.colours.length; i++ )
-        {
-            this.colours[i] = new TextBuffer( colours[i] );
-        }
+        for( int i = 0; i < this.colours.length; i++ ) this.colours[i] = new TextBuffer( colours[i] );
 
         page = 0;
         pages = Math.max( this.text.length / ItemPrintout.LINES_PER_PAGE, 1 );
-        book = ((ItemPrintout) container.getStack()
-            .getItem()).getType() == ItemPrintout.Type.BOOK;
+        book = ((ItemPrintout) container.getStack().getItem()).getType() == ItemPrintout.Type.BOOK;
+    }
+
+    @Override
+    public boolean keyPressed( int key, int scancode, int modifiers )
+    {
+        if( super.keyPressed( key, scancode, modifiers ) ) return true;
+
+        if( key == GLFW.GLFW_KEY_RIGHT )
+        {
+            if( page < pages - 1 ) page++;
+            return true;
+        }
+
+        if( key == GLFW.GLFW_KEY_LEFT )
+        {
+            if( page > 0 ) page--;
+            return true;
+        }
+
+        return false;
     }
 
     @Override
     public boolean mouseScrolled( double x, double y, double delta )
     {
-        if( super.mouseScrolled( x, y, delta ) )
-        {
-            return true;
-        }
+        if( super.mouseScrolled( x, y, delta ) ) return true;
         if( delta < 0 )
         {
             // Scroll up goes to the next page
-            if( page < pages - 1 )
-            {
-                page++;
-            }
+            if( page < pages - 1 ) page++;
             return true;
         }
 
         if( delta > 0 )
         {
             // Scroll down goes to the previous page
-            if( page > 0 )
-            {
-                page--;
-            }
+            if( page > 0 ) page--;
             return true;
         }
 
         return false;
     }
 
+    @Override
+    protected void renderBg( @Nonnull PoseStack transform, float partialTicks, int mouseX, int mouseY )
+    {
+        // Draw the printout
+        RenderSystem.setShaderColor( 1.0f, 1.0f, 1.0f, 1.0f );
+        RenderSystem.enableDepthTest();
+
+        MultiBufferSource.BufferSource renderer = MultiBufferSource.immediate( Tesselator.getInstance().getBuilder() );
+        Matrix4f matrix = transform.last().pose();
+        drawBorder( matrix, renderer, leftPos, topPos, getBlitOffset(), page, pages, book, FULL_BRIGHT_LIGHTMAP );
+        drawText( matrix, renderer, leftPos + X_TEXT_MARGIN, topPos + Y_TEXT_MARGIN, ItemPrintout.LINES_PER_PAGE * page, FULL_BRIGHT_LIGHTMAP, text, colours );
+        renderer.endBatch();
+    }
+
     @Override
     public void render( @Nonnull PoseStack stack, int mouseX, int mouseY, float partialTicks )
     {
@@ -104,50 +121,4 @@ public class GuiPrintout extends AbstractContainerScreen<ContainerHeldItem>
     {
         // Skip rendering labels.
     }
-
-    @Override
-    protected void renderBg( @Nonnull PoseStack transform, float partialTicks, int mouseX, int mouseY )
-    {
-        // Draw the printout
-        RenderSystem.setShaderColor( 1.0f, 1.0f, 1.0f, 1.0f );
-        RenderSystem.enableDepthTest();
-
-        MultiBufferSource.BufferSource renderer = Minecraft.getInstance()
-            .renderBuffers()
-            .bufferSource();
-        Matrix4f matrix = transform.last()
-            .pose();
-        drawBorder( matrix, renderer, leftPos, topPos, getBlitOffset(), page, pages, book, FULL_BRIGHT_LIGHTMAP );
-        drawText( matrix, renderer, leftPos + X_TEXT_MARGIN, topPos + Y_TEXT_MARGIN, ItemPrintout.LINES_PER_PAGE * page, FULL_BRIGHT_LIGHTMAP, text, colours );
-        renderer.endBatch();
-    }
-
-    @Override
-    public boolean keyPressed( int key, int scancode, int modifiers )
-    {
-        if( super.keyPressed( key, scancode, modifiers ) )
-        {
-            return true;
-        }
-
-        if( key == GLFW.GLFW_KEY_RIGHT )
-        {
-            if( page < pages - 1 )
-            {
-                page++;
-            }
-            return true;
-        }
-
-        if( key == GLFW.GLFW_KEY_LEFT )
-        {
-            if( page > 0 )
-            {
-                page--;
-            }
-            return true;
-        }
-
-        return false;
-    }
 }

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

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.client.gui;
 
 import com.mojang.blaze3d.systems.RenderSystem;
@@ -20,12 +19,12 @@ import net.minecraft.world.entity.player.Inventory;
 
 import javax.annotation.Nonnull;
 
-import static dan200.computercraft.shared.turtle.inventory.ContainerTurtle.BORDER;
+import static dan200.computercraft.shared.turtle.inventory.ContainerTurtle.*;
 
 public class GuiTurtle extends ComputerScreenBase<ContainerTurtle>
 {
-    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 static final ResourceLocation BACKGROUND_NORMAL = new ResourceLocation( ComputerCraft.MOD_ID, "textures/gui/turtle_normal.png" );
+    private static final ResourceLocation BACKGROUND_ADVANCED = new ResourceLocation( ComputerCraft.MOD_ID, "textures/gui/turtle_advanced.png" );
 
     private static final int TEX_WIDTH = 254;
     private static final int TEX_HEIGHT = 217;
@@ -35,11 +34,10 @@ public class GuiTurtle extends ComputerScreenBase<ContainerTurtle>
     public GuiTurtle( ContainerTurtle container, Inventory player, Component title )
     {
         super( container, player, title, BORDER );
-
         family = container.getFamily();
+
         imageWidth = TEX_WIDTH + ComputerSidebar.WIDTH;
         imageHeight = TEX_HEIGHT;
-
     }
 
     @Override
@@ -52,23 +50,22 @@ public class GuiTurtle extends ComputerScreenBase<ContainerTurtle>
     }
 
     @Override
-    public void renderBg( @Nonnull PoseStack transform, float partialTicks, int mouseX, int mouseY )
+    protected void renderBg( @Nonnull PoseStack transform, float partialTicks, int mouseX, int mouseY )
     {
         boolean advanced = family == ComputerFamily.ADVANCED;
         RenderSystem.setShaderTexture( 0, advanced ? BACKGROUND_ADVANCED : BACKGROUND_NORMAL );
         blit( transform, leftPos + ComputerSidebar.WIDTH, topPos, 0, 0, TEX_WIDTH, TEX_HEIGHT );
 
-        // Draw selection slot
         int slot = getMenu().getSelectedSlot();
         if( slot >= 0 )
         {
+            RenderSystem.setShaderColor( 1.0F, 1.0F, 1.0F, 1.0F );
             int slotX = slot % 4;
             int slotY = slot / 4;
-            blit( transform, leftPos + ContainerTurtle.TURTLE_START_X - 2 + slotX * 18, topPos + ContainerTurtle.PLAYER_START_Y - 2 + slotY * 18,
-                0,
-                217,
-                24,
-                24 );
+            blit( transform,
+                leftPos + TURTLE_START_X - 2 + slotX * 18, topPos + PLAYER_START_Y - 2 + slotY * 18,
+                0, 217, 24, 24
+            );
         }
 
         RenderSystem.setShaderTexture( 0, advanced ? ComputerBorderRenderer.BACKGROUND_ADVANCED : ComputerBorderRenderer.BACKGROUND_NORMAL );

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

@@ -10,6 +10,7 @@ import dan200.computercraft.ComputerCraft;
 import dan200.computercraft.client.gui.widgets.WidgetTerminal;
 import dan200.computercraft.shared.computer.core.ClientComputer;
 import dan200.computercraft.shared.computer.inventory.ContainerComputerBase;
+import net.minecraft.client.KeyMapping;
 import net.minecraft.client.gui.Font;
 import net.minecraft.client.gui.screens.Screen;
 import net.minecraft.client.gui.screens.inventory.MenuAccess;
@@ -43,9 +44,13 @@ public class NoTermComputerScreen<T extends ContainerComputerBase> extends Scree
     @Override
     protected void init()
     {
-        this.passEvents = true;
+        passEvents = true; // Pass mouse vents through to the game's mouse handler.
+        // First ensure we're still grabbing the mouse, so the user can look around. Then reset bits of state that
+        // grabbing unsets.
         minecraft.mouseHandler.grabMouse();
         minecraft.screen = this;
+        KeyMapping.releaseAll();
+
         super.init();
         minecraft.keyboardHandler.setSendRepeatsToGui( true );
 
@@ -102,7 +107,7 @@ public class NoTermComputerScreen<T extends ContainerComputerBase> extends Scree
     }
 
     @Override
-    public void render( PoseStack transform, int mouseX, int mouseY, float partialTicks )
+    public void render( @Nonnull PoseStack transform, int mouseX, int mouseY, float partialTicks )
     {
         super.render( transform, mouseX, mouseY, partialTicks );
 

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

@@ -49,9 +49,9 @@ public final class OptionScreen extends Screen
         this.originalScreen = originalScreen;
     }
 
-    public static void show( Minecraft client, Component title, Component message, List<AbstractWidget> buttons, Runnable exit )
+    public static void show( Minecraft minecraft, Component title, Component message, List<AbstractWidget> buttons, Runnable exit )
     {
-        client.setScreen( new OptionScreen( title, message, buttons, exit, unwrap( client.screen ) ) );
+        minecraft.setScreen( new OptionScreen( title, message, buttons, exit, unwrap( minecraft.screen ) ) );
     }
 
     public static Screen unwrap( Screen screen )

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

@@ -8,7 +8,6 @@ package dan200.computercraft.client.gui.widgets;
 import com.mojang.blaze3d.vertex.PoseStack;
 import dan200.computercraft.ComputerCraft;
 import dan200.computercraft.client.render.ComputerBorderRenderer;
-import dan200.computercraft.shared.command.text.ChatHelpers;
 import dan200.computercraft.shared.computer.core.ClientComputer;
 import net.minecraft.ChatFormatting;
 import net.minecraft.client.gui.components.AbstractWidget;
@@ -55,10 +54,10 @@ public final class ComputerSidebar
             TEXTURE, TEX_SIZE, TEX_SIZE, b -> toggleComputer( computer ),
             () -> computer.isOn() ? Arrays.asList(
                 new TranslatableComponent( "gui.computercraft.tooltip.turn_off" ),
-                ChatHelpers.coloured( new TranslatableComponent( "gui.computercraft.tooltip.turn_off.key" ), ChatFormatting.GRAY )
+                new TranslatableComponent( "gui.computercraft.tooltip.turn_off.key" ).withStyle( ChatFormatting.GRAY )
             ) : Arrays.asList(
                 new TranslatableComponent( "gui.computercraft.tooltip.turn_on" ),
-                ChatHelpers.coloured( new TranslatableComponent( "gui.computercraft.tooltip.turn_off.key" ), ChatFormatting.GRAY )
+                new TranslatableComponent( "gui.computercraft.tooltip.turn_off.key" ).withStyle( ChatFormatting.GRAY )
             )
         ) );
 
@@ -69,7 +68,7 @@ public final class ComputerSidebar
             TEXTURE, TEX_SIZE, TEX_SIZE, b -> computer.queueEvent( "terminate" ),
             Arrays.asList(
                 new TranslatableComponent( "gui.computercraft.tooltip.terminate" ),
-                ChatHelpers.coloured( new TranslatableComponent( "gui.computercraft.tooltip.terminate.key" ), ChatFormatting.GRAY )
+                new TranslatableComponent( "gui.computercraft.tooltip.terminate.key" ).withStyle( ChatFormatting.GRAY )
             )
         ) );
     }

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

@@ -7,6 +7,7 @@ package dan200.computercraft.client.gui.widgets;
 
 import com.mojang.blaze3d.systems.RenderSystem;
 import com.mojang.blaze3d.vertex.PoseStack;
+import dan200.computercraft.shared.util.NonNullSupplier;
 import net.minecraft.client.gui.components.Button;
 import net.minecraft.client.gui.screens.Screen;
 import net.minecraft.network.chat.Component;
@@ -16,7 +17,6 @@ import net.minecraft.resources.ResourceLocation;
 import javax.annotation.Nonnull;
 import java.util.List;
 import java.util.function.IntSupplier;
-import java.util.function.Supplier;
 
 /**
  * Version of {@link net.minecraft.client.gui.components.ImageButton} which allows changing some properties
@@ -31,7 +31,7 @@ public class DynamicImageButton extends Button
     private final int yDiffTex;
     private final int textureWidth;
     private final int textureHeight;
-    private final Supplier<List<Component>> tooltip;
+    private final NonNullSupplier<List<Component>> tooltip;
 
     public DynamicImageButton(
         Screen screen, int x, int y, int width, int height, int xTexStart, int yTexStart, int yDiffTex,
@@ -50,7 +50,7 @@ public class DynamicImageButton extends Button
     public DynamicImageButton(
         Screen screen, int x, int y, int width, int height, IntSupplier xTexStart, int yTexStart, int yDiffTex,
         ResourceLocation texture, int textureWidth, int textureHeight,
-        OnPress onPress, Supplier<List<Component>> tooltip
+        OnPress onPress, NonNullSupplier<List<Component>> tooltip
     )
     {
         super( x, y, width, height, TextComponent.EMPTY, onPress );
@@ -71,12 +71,12 @@ public class DynamicImageButton extends Button
         RenderSystem.disableDepthTest();
 
         int yTex = yTexStart;
-        if( isHovered() ) yTex += yDiffTex;
+        if( isHoveredOrFocused() ) yTex += yDiffTex;
 
         blit( stack, x, y, xTexStart.getAsInt(), yTex, width, height, textureWidth, textureHeight );
         RenderSystem.enableDepthTest();
 
-        if( isHovered() ) renderToolTip( stack, mouseX, mouseY );
+        if( isHovered ) renderToolTip( stack, mouseX, mouseY );
     }
 
     @Nonnull
@@ -87,11 +87,10 @@ public class DynamicImageButton extends Button
         return tooltip.isEmpty() ? TextComponent.EMPTY : tooltip.get( 0 );
     }
 
-    // @Override
+    @Override
     public void renderToolTip( @Nonnull PoseStack stack, int mouseX, int mouseY )
     {
         List<Component> tooltip = this.tooltip.get();
-
         if( !tooltip.isEmpty() )
         {
             screen.renderComponentTooltip( stack, tooltip, mouseX, mouseY );

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

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.client.gui.widgets;
 
 import com.mojang.blaze3d.vertex.PoseStack;
@@ -65,15 +64,104 @@ public class WidgetTerminal extends AbstractWidget
         if( ch >= 32 && ch <= 126 || ch >= 160 && ch <= 255 ) // printable chars in byte range
         {
             // Queue the "char" event
-            queueEvent( "char", Character.toString( ch ) );
+            computer.queueEvent( "char", new Object[] { Character.toString( ch ) } );
         }
 
         return true;
     }
 
-    private boolean inTermRegion( double mouseX, double mouseY )
+    @Override
+    public boolean keyPressed( int key, int scancode, int modifiers )
     {
-        return active && visible && mouseX >= innerX && mouseY >= innerY && mouseX < innerX + innerWidth && mouseY < innerY + innerHeight;
+        if( key == GLFW.GLFW_KEY_ESCAPE ) return false;
+        if( (modifiers & GLFW.GLFW_MOD_CONTROL) != 0 )
+        {
+            switch( key )
+            {
+                case GLFW.GLFW_KEY_T:
+                    if( terminateTimer < 0 ) terminateTimer = 0;
+                    return true;
+                case GLFW.GLFW_KEY_S:
+                    if( shutdownTimer < 0 ) shutdownTimer = 0;
+                    return true;
+                case GLFW.GLFW_KEY_R:
+                    if( rebootTimer < 0 ) rebootTimer = 0;
+                    return true;
+
+                case GLFW.GLFW_KEY_V:
+                    // Ctrl+V for paste
+                    String clipboard = Minecraft.getInstance().keyboardHandler.getClipboard();
+                    if( clipboard != null )
+                    {
+                        // Clip to the first occurrence of \r or \n
+                        int newLineIndex1 = clipboard.indexOf( "\r" );
+                        int newLineIndex2 = clipboard.indexOf( "\n" );
+                        if( newLineIndex1 >= 0 && newLineIndex2 >= 0 )
+                        {
+                            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 );
+                        }
+
+                        // Filter the string
+                        clipboard = SharedConstants.filterText( clipboard );
+                        if( !clipboard.isEmpty() )
+                        {
+                            // Clip to 512 characters and queue the event
+                            if( clipboard.length() > 512 ) clipboard = clipboard.substring( 0, 512 );
+                            computer.queueEvent( "paste", new Object[] { clipboard } );
+                        }
+
+                        return true;
+                    }
+            }
+        }
+
+        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 );
+            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 );
+            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
@@ -175,113 +263,27 @@ public class WidgetTerminal extends AbstractWidget
         return true;
     }
 
-    @Override
-    public boolean keyPressed( int key, int scancode, int modifiers )
+    private boolean inTermRegion( double mouseX, double mouseY )
     {
-        if( key == GLFW.GLFW_KEY_ESCAPE )
-        {
-            return false;
-        }
-        if( (modifiers & GLFW.GLFW_MOD_CONTROL) != 0 )
-        {
-            switch( key )
-            {
-                case GLFW.GLFW_KEY_T:
-                    if( terminateTimer < 0 )
-                    {
-                        terminateTimer = 0;
-                    }
-                    return true;
-                case GLFW.GLFW_KEY_S:
-                    if( shutdownTimer < 0 )
-                    {
-                        shutdownTimer = 0;
-                    }
-                    return true;
-                case GLFW.GLFW_KEY_R:
-                    if( rebootTimer < 0 )
-                    {
-                        rebootTimer = 0;
-                    }
-                    return true;
-
-                case GLFW.GLFW_KEY_V:
-                    // Ctrl+V for paste
-                    String clipboard = Minecraft.getInstance().keyboardHandler.getClipboard();
-                    if( clipboard != null )
-                    {
-                        // Clip to the first occurrence of \r or \n
-                        int newLineIndex1 = clipboard.indexOf( "\r" );
-                        int newLineIndex2 = clipboard.indexOf( "\n" );
-                        if( newLineIndex1 >= 0 && newLineIndex2 >= 0 )
-                        {
-                            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 );
-                        }
-
-                        // Filter the string
-                        clipboard = SharedConstants.filterText( clipboard );
-                        if( !clipboard.isEmpty() )
-                        {
-                            // Clip to 512 characters and queue the event
-                            if( clipboard.length() > 512 )
-                            {
-                                clipboard = clipboard.substring( 0, 512 );
-                            }
-                            queueEvent( "paste", clipboard );
-                        }
-
-                        return true;
-                    }
-            }
-        }
-
-        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 );
-            computer.keyDown( key, repeat );
-        }
-
-        return true;
+        return active && visible && mouseX >= innerX && mouseY >= innerY && mouseX < innerX + innerWidth && mouseY < innerY + innerHeight;
     }
 
-    @Override
-    public boolean keyReleased( int key, int scancode, int modifiers )
+    public void update()
     {
-        // Queue the "key_up" event and remove from the down set
-        if( key >= 0 && keysDown.get( key ) )
+        if( terminateTimer >= 0 && terminateTimer < TERMINATE_TIME && (terminateTimer += 0.05f) > TERMINATE_TIME )
         {
-            keysDown.set( key, false );
-            computer.keyUp( key );
+            computer.queueEvent( "terminate" );
         }
 
-        switch( key )
+        if( shutdownTimer >= 0 && shutdownTimer < TERMINATE_TIME && (shutdownTimer += 0.05f) > TERMINATE_TIME )
         {
-            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;
+            computer.shutdown();
         }
 
-        return true;
+        if( rebootTimer >= 0 && rebootTimer < TERMINATE_TIME && (rebootTimer += 0.05f) > TERMINATE_TIME )
+        {
+            computer.reboot();
+        }
     }
 
     @Override
@@ -307,44 +309,6 @@ public class WidgetTerminal extends AbstractWidget
         }
     }
 
-    @Override
-    public boolean isMouseOver( double x, double y )
-    {
-        return true;
-    }
-
-    private void queueEvent( String event, Object... args )
-    {
-        computer.queueEvent( event, args );
-    }
-
-    public void update()
-    {
-        if( terminateTimer >= 0 && terminateTimer < TERMINATE_TIME && (terminateTimer += 0.05f) > TERMINATE_TIME )
-        {
-            queueEvent( "terminate" );
-        }
-
-        if( shutdownTimer >= 0 && shutdownTimer < TERMINATE_TIME && (shutdownTimer += 0.05f) > TERMINATE_TIME )
-        {
-            computer.shutdown();
-        }
-
-        if( rebootTimer >= 0 && rebootTimer < TERMINATE_TIME && (rebootTimer += 0.05f) > TERMINATE_TIME )
-        {
-            computer.reboot();
-        }
-    }
-
-    private void queueEvent( String event )
-    {
-        ClientComputer computer = this.computer;
-        if( computer != null )
-        {
-            computer.queueEvent( event );
-        }
-    }
-
     @Override
     public void render( @Nonnull PoseStack transform, int mouseX, int mouseY, float partialTicks )
     {
@@ -362,9 +326,9 @@ public class WidgetTerminal extends AbstractWidget
     }
 
     @Override
-    public void updateNarration( NarrationElementOutput builder )
+    public void updateNarration( @Nonnull NarrationElementOutput output )
     {
-
+        // I'm not sure what the right option is here.
     }
 
     public static int getWidth( int termWidth )

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

@@ -14,8 +14,8 @@ import dan200.computercraft.client.render.TileEntityMonitorRenderer;
 import dan200.computercraft.client.render.TileEntityTurtleRenderer;
 import dan200.computercraft.client.render.TurtleModelLoader;
 import dan200.computercraft.client.render.TurtlePlayerRenderer;
-import dan200.computercraft.fabric.events.ClientUnloadWorldEvent;
-import dan200.computercraft.shared.ComputerCraftRegistry;
+import dan200.computercraft.fabric.events.ComputerCraftCustomEvents;
+import dan200.computercraft.shared.Registry;
 import dan200.computercraft.shared.common.ContainerHeldItem;
 import dan200.computercraft.shared.common.IColouredItem;
 import dan200.computercraft.shared.common.TileGeneric;
@@ -23,6 +23,7 @@ import dan200.computercraft.shared.computer.inventory.ContainerComputerBase;
 import dan200.computercraft.shared.computer.inventory.ContainerViewComputer;
 import dan200.computercraft.shared.peripheral.diskdrive.ContainerDiskDrive;
 import dan200.computercraft.shared.peripheral.monitor.ClientMonitor;
+import dan200.computercraft.shared.peripheral.monitor.MonitorWatcher;
 import dan200.computercraft.shared.peripheral.printer.ContainerPrinter;
 import dan200.computercraft.shared.pocket.items.ItemPocketComputer;
 import dan200.computercraft.shared.turtle.inventory.ContainerTurtle;
@@ -60,7 +61,7 @@ public final class ComputerCraftProxyClient implements ClientModInitializer
             }
         } );
 
-        ClientUnloadWorldEvent.EVENT.register( () -> ClientMonitor.destroyAll() );
+        ComputerCraftCustomEvents.CLIENT_UNLOAD_WORLD_EVENT.register( () -> ClientMonitor.destroyAll() );
 
         // Config
         ClientLifecycleEvents.CLIENT_STARTED.register( Config::clientStarted );
@@ -70,20 +71,21 @@ public final class ComputerCraftProxyClient implements ClientModInitializer
     public void onInitializeClient()
     {
         FrameInfo.init();
+        MonitorWatcher.init();
         registerContainers();
 
         // While turtles themselves are not transparent, their upgrades may be.
-        BlockRenderLayerMap.INSTANCE.putBlock( ComputerCraftRegistry.ModBlocks.TURTLE_NORMAL, RenderType.translucent() );
-        BlockRenderLayerMap.INSTANCE.putBlock( ComputerCraftRegistry.ModBlocks.TURTLE_ADVANCED, RenderType.translucent() );
+        BlockRenderLayerMap.INSTANCE.putBlock( Registry.ModBlocks.TURTLE_NORMAL, RenderType.translucent() );
+        BlockRenderLayerMap.INSTANCE.putBlock( Registry.ModBlocks.TURTLE_ADVANCED, RenderType.translucent() );
         // Monitors' textures have transparent fronts and so count as cutouts.
-        BlockRenderLayerMap.INSTANCE.putBlock( ComputerCraftRegistry.ModBlocks.MONITOR_NORMAL, RenderType.cutout() );
-        BlockRenderLayerMap.INSTANCE.putBlock( ComputerCraftRegistry.ModBlocks.MONITOR_ADVANCED, RenderType.cutout() );
+        BlockRenderLayerMap.INSTANCE.putBlock( Registry.ModBlocks.MONITOR_NORMAL, RenderType.cutout() );
+        BlockRenderLayerMap.INSTANCE.putBlock( Registry.ModBlocks.MONITOR_ADVANCED, RenderType.cutout() );
 
         // Setup TESRs
-        BlockEntityRendererRegistry.register( ComputerCraftRegistry.ModTiles.MONITOR_NORMAL, TileEntityMonitorRenderer::new );
-        BlockEntityRendererRegistry.register( ComputerCraftRegistry.ModTiles.MONITOR_ADVANCED, TileEntityMonitorRenderer::new );
-        BlockEntityRendererRegistry.register( ComputerCraftRegistry.ModTiles.TURTLE_NORMAL, TileEntityTurtleRenderer::new );
-        BlockEntityRendererRegistry.register( ComputerCraftRegistry.ModTiles.TURTLE_ADVANCED, TileEntityTurtleRenderer::new );
+        BlockEntityRendererRegistry.register( Registry.ModBlockEntities.MONITOR_NORMAL, TileEntityMonitorRenderer::new );
+        BlockEntityRendererRegistry.register( Registry.ModBlockEntities.MONITOR_ADVANCED, TileEntityMonitorRenderer::new );
+        BlockEntityRendererRegistry.register( Registry.ModBlockEntities.TURTLE_NORMAL, TileEntityTurtleRenderer::new );
+        BlockEntityRendererRegistry.register( Registry.ModBlockEntities.TURTLE_ADVANCED, TileEntityTurtleRenderer::new );
 
         ClientSpriteRegistryCallback.event( InventoryMenu.BLOCK_ATLAS )
             .register( ClientRegistry::onTextureStitchEvent );
@@ -92,17 +94,17 @@ public final class ComputerCraftProxyClient implements ClientModInitializer
             TurtleModelLoader.INSTANCE.loadModel(
                 name ) : null );
 
-        EntityRendererRegistry.register( ComputerCraftRegistry.ModEntities.TURTLE_PLAYER, TurtlePlayerRenderer::new );
+        EntityRendererRegistry.register( Registry.ModEntities.TURTLE_PLAYER, TurtlePlayerRenderer::new );
 
         registerItemProperty( "state",
             ( stack, world, player, integer ) -> ItemPocketComputer.getState( stack )
                 .ordinal(),
-            () -> ComputerCraftRegistry.ModItems.POCKET_COMPUTER_NORMAL,
-            () -> ComputerCraftRegistry.ModItems.POCKET_COMPUTER_ADVANCED );
+            () -> Registry.ModItems.POCKET_COMPUTER_NORMAL,
+            () -> Registry.ModItems.POCKET_COMPUTER_ADVANCED );
         registerItemProperty( "state",
             ( stack, world, player, integer ) -> IColouredItem.getColourBasic( stack ) != -1 ? 1 : 0,
-            () -> ComputerCraftRegistry.ModItems.POCKET_COMPUTER_NORMAL,
-            () -> ComputerCraftRegistry.ModItems.POCKET_COMPUTER_ADVANCED );
+            () -> Registry.ModItems.POCKET_COMPUTER_NORMAL,
+            () -> Registry.ModItems.POCKET_COMPUTER_ADVANCED );
         ClientRegistry.onItemColours();
 
         initEvents();
@@ -111,18 +113,18 @@ public final class ComputerCraftProxyClient implements ClientModInitializer
     // My IDE doesn't think so, but we do actually need these generics.
     private static void registerContainers()
     {
-        ScreenRegistry.<ContainerComputerBase, GuiComputer<ContainerComputerBase>>register( ComputerCraftRegistry.ModContainers.COMPUTER, GuiComputer::create );
-        ScreenRegistry.<ContainerComputerBase, GuiComputer<ContainerComputerBase>>register( ComputerCraftRegistry.ModContainers.POCKET_COMPUTER,
+        ScreenRegistry.<ContainerComputerBase, GuiComputer<ContainerComputerBase>>register( Registry.ModContainers.COMPUTER, GuiComputer::create );
+        ScreenRegistry.<ContainerComputerBase, GuiComputer<ContainerComputerBase>>register( Registry.ModContainers.POCKET_COMPUTER,
             GuiComputer::createPocket );
-        ScreenRegistry.<ContainerComputerBase, NoTermComputerScreen<ContainerComputerBase>>register( ComputerCraftRegistry.ModContainers.POCKET_COMPUTER_NO_TERM,
+        ScreenRegistry.<ContainerComputerBase, NoTermComputerScreen<ContainerComputerBase>>register( Registry.ModContainers.POCKET_COMPUTER_NO_TERM,
             NoTermComputerScreen::new );
-        ScreenRegistry.<ContainerTurtle, GuiTurtle>register( ComputerCraftRegistry.ModContainers.TURTLE, GuiTurtle::new );
+        ScreenRegistry.<ContainerTurtle, GuiTurtle>register( Registry.ModContainers.TURTLE, GuiTurtle::new );
 
-        ScreenRegistry.<ContainerPrinter, GuiPrinter>register( ComputerCraftRegistry.ModContainers.PRINTER, GuiPrinter::new );
-        ScreenRegistry.<ContainerDiskDrive, GuiDiskDrive>register( ComputerCraftRegistry.ModContainers.DISK_DRIVE, GuiDiskDrive::new );
-        ScreenRegistry.<ContainerHeldItem, GuiPrintout>register( ComputerCraftRegistry.ModContainers.PRINTOUT, GuiPrintout::new );
+        ScreenRegistry.<ContainerPrinter, GuiPrinter>register( Registry.ModContainers.PRINTER, GuiPrinter::new );
+        ScreenRegistry.<ContainerDiskDrive, GuiDiskDrive>register( Registry.ModContainers.DISK_DRIVE, GuiDiskDrive::new );
+        ScreenRegistry.<ContainerHeldItem, GuiPrintout>register( Registry.ModContainers.PRINTOUT, GuiPrintout::new );
 
-        ScreenRegistry.<ContainerViewComputer, GuiComputer<ContainerViewComputer>>register( ComputerCraftRegistry.ModContainers.VIEW_COMPUTER,
+        ScreenRegistry.<ContainerViewComputer, GuiComputer<ContainerViewComputer>>register( Registry.ModContainers.VIEW_COMPUTER,
             GuiComputer::createView );
     }
 

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

@@ -3,14 +3,13 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.client.render;
 
 import com.mojang.blaze3d.vertex.PoseStack;
 import com.mojang.blaze3d.vertex.VertexConsumer;
 import com.mojang.math.Matrix3f;
 import com.mojang.math.Matrix4f;
-import dan200.computercraft.shared.ComputerCraftRegistry;
+import dan200.computercraft.shared.Registry;
 import dan200.computercraft.shared.peripheral.modem.wired.BlockCable;
 import dan200.computercraft.shared.peripheral.modem.wired.CableShapes;
 import dan200.computercraft.shared.util.WorldUtil;
@@ -33,35 +32,34 @@ public final class CableHighlightRenderer
     {
     }
 
-    public static boolean drawHighlight( PoseStack stack, VertexConsumer consumer, Entity entity, double d, double e, double f, BlockPos pos,
-                                         BlockState state )
+    /*
+     * Draw an outline for a specific part of a cable "Multipart".
+     *
+     * @see net.minecraft.client.renderer.LevelRenderer#renderHitOutline
+     */
+    public static boolean drawHighlight( PoseStack stack, VertexConsumer buffer, Entity entity, double d, double e, double f, BlockPos pos, BlockState state )
     {
+        HitResult hitResult = Minecraft.getInstance().hitResult;
         Camera info = Minecraft.getInstance().gameRenderer.getMainCamera();
 
         // We only care about instances with both cable and modem.
-        if( state.getBlock() != ComputerCraftRegistry.ModBlocks.CABLE || state.getValue( BlockCable.MODEM )
-            .getFacing() == null || !state.getValue( BlockCable.CABLE ) )
+        if( state.getBlock() != Registry.ModBlocks.CABLE || state.getValue( BlockCable.MODEM ).getFacing() == null || !state.getValue( BlockCable.CABLE ) )
         {
             return false;
         }
 
-        HitResult hitResult = Minecraft.getInstance().hitResult;
-
         Vec3 hitPos = hitResult != null ? hitResult.getLocation() : new Vec3( d, e, f );
 
-        VoxelShape shape = WorldUtil.isVecInside( CableShapes.getModemShape( state ),
-            hitPos.subtract( pos.getX(),
-                pos.getY(),
-                pos.getZ() ) ) ? CableShapes.getModemShape( state ) : CableShapes.getCableShape(
-            state );
+        VoxelShape shape = WorldUtil.isVecInside( CableShapes.getModemShape( state ), hitPos.subtract( pos.getX(), pos.getY(), pos.getZ() ) )
+            ? CableShapes.getModemShape( state )
+            : CableShapes.getCableShape( state );
 
         Vec3 cameraPos = info.getPosition();
-
         double xOffset = pos.getX() - cameraPos.x();
         double yOffset = pos.getY() - cameraPos.y();
         double zOffset = pos.getZ() - cameraPos.z();
-        Matrix4f matrix4f = stack.last()
-            .pose();
+
+        Matrix4f matrix4f = stack.last().pose();
         Matrix3f normal = stack.last().normal();
         shape.forAllEdges( ( x1, y1, z1, x2, y2, z2 ) -> {
             float xDelta = (float) (x2 - x1);
@@ -72,11 +70,13 @@ public final class CableHighlightRenderer
             yDelta = yDelta / len;
             zDelta = zDelta / len;
 
-            consumer.vertex( matrix4f, (float) (x1 + xOffset), (float) (y1 + yOffset), (float) (z1 + zOffset) )
+            buffer
+                .vertex( matrix4f, (float) (x1 + xOffset), (float) (y1 + yOffset), (float) (z1 + zOffset) )
                 .color( 0, 0, 0, 0.4f )
                 .normal( normal, xDelta, yDelta, zDelta )
                 .endVertex();
-            consumer.vertex( matrix4f, (float) (x2 + xOffset), (float) (y2 + yOffset), (float) (z2 + zOffset) )
+            buffer
+                .vertex( matrix4f, (float) (x2 + xOffset), (float) (y2 + yOffset), (float) (z2 + zOffset) )
                 .color( 0, 0, 0, 0.4f )
                 .normal( normal, xDelta, yDelta, zDelta )
                 .endVertex();

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

@@ -22,15 +22,24 @@ public class ComputerBorderRenderer
     public static final ResourceLocation BACKGROUND_ADVANCED = new ResourceLocation( ComputerCraft.MOD_ID, "textures/gui/corners_advanced.png" );
     public static final ResourceLocation BACKGROUND_COMMAND = new ResourceLocation( ComputerCraft.MOD_ID, "textures/gui/corners_command.png" );
     public static final ResourceLocation BACKGROUND_COLOUR = new ResourceLocation( ComputerCraft.MOD_ID, "textures/gui/corners_colour.png" );
+
+    private static final Matrix4f IDENTITY = new Matrix4f();
+
+    static
+    {
+        IDENTITY.setIdentity();
+    }
+
     /**
      * The margin between the terminal and its border.
      */
     public static final int MARGIN = 2;
+
     /**
      * The width of the terminal border.
      */
     public static final int BORDER = 12;
-    private static final Matrix4f IDENTITY = new Matrix4f();
+
     private static final int CORNER_TOP_Y = 28;
     private static final int CORNER_BOTTOM_Y = CORNER_TOP_Y + BORDER;
     private static final int CORNER_LEFT_X = BORDER;
@@ -40,21 +49,16 @@ public class ComputerBorderRenderer
     private static final int LIGHT_CORNER_Y = 80;
 
     public static final int LIGHT_HEIGHT = 8;
+
     public static final int TEX_SIZE = 256;
     private static final float TEX_SCALE = 1 / (float) TEX_SIZE;
 
-    static
-    {
-        IDENTITY.setIdentity();
-    }
-
     private final Matrix4f transform;
     private final VertexConsumer builder;
+    private final int light;
     private final int z;
     private final float r, g, b;
 
-    private final int light;
-
     public ComputerBorderRenderer( Matrix4f transform, VertexConsumer builder, int z, int light, float r, float g, float b )
     {
         this.transform = transform;
@@ -82,14 +86,19 @@ public class ComputerBorderRenderer
         }
     }
 
+    public static RenderType getRenderType( ResourceLocation location )
+    {
+        // See note in RenderTypes about why we use text rather than anything intuitive.
+        return RenderType.text( location );
+    }
+
     public static void render( ResourceLocation location, int x, int y, int z, int light, int width, int height )
     {
         MultiBufferSource.BufferSource source = MultiBufferSource.immediate( Tesselator.getInstance().getBuilder() );
-        render( IDENTITY, source.getBuffer( RenderType.text( location ) ), x, y, z, light, width, height, false, 1, 1, 1 );
+        render( IDENTITY, source.getBuffer( getRenderType( location ) ), x, y, z, light, width, height, false, 1, 1, 1 );
         source.endBatch();
     }
 
-
     public static void render( Matrix4f transform, VertexConsumer buffer, int x, int y, int z, int light, int width, int height, boolean withLight, float r, float g, float b )
     {
         new ComputerBorderRenderer( transform, buffer, z, light, r, g, b ).doRender( x, y, width, height, withLight );
@@ -125,16 +134,16 @@ public class ComputerBorderRenderer
         }
     }
 
-    private void renderLine( int x, int y, int u, int v, int width, int height )
-    {
-        renderTexture( x, y, u, v, width, height, BORDER, BORDER );
-    }
-
     private void renderCorner( int x, int y, int u, int v )
     {
         renderTexture( x, y, u, v, BORDER, BORDER, BORDER, BORDER );
     }
 
+    private void renderLine( int x, int y, int u, int v, int width, int height )
+    {
+        renderTexture( x, y, u, v, width, height, BORDER, BORDER );
+    }
+
     private void renderTexture( int x, int y, int u, int v, int width, int height )
     {
         renderTexture( x, y, u, v, width, height, width, height );
@@ -142,25 +151,9 @@ public class ComputerBorderRenderer
 
     private void renderTexture( int x, int y, int u, int v, int width, int height, int textureWidth, int textureHeight )
     {
-        builder.vertex( transform, x, y + height, z )
-            .color( r, g, b, 1.0f )
-            .uv( u * TEX_SCALE, (v + textureHeight) * TEX_SCALE )
-            .uv2( light )
-            .endVertex();
-        builder.vertex( transform, x + width, y + height, z )
-            .color( r, g, b, 1.0f )
-            .uv( (u + textureWidth) * TEX_SCALE, (v + textureHeight) * TEX_SCALE )
-            .uv2( light )
-            .endVertex();
-        builder.vertex( transform, x + width, y, z )
-            .color( r, g, b, 1.0f )
-            .uv( (u + textureWidth) * TEX_SCALE, v * TEX_SCALE )
-            .uv2( light )
-            .endVertex();
-        builder.vertex( transform, x, y, z )
-            .color( r, g, b, 1.0f )
-            .uv( u * TEX_SCALE, v * TEX_SCALE )
-            .uv2( light )
-            .endVertex();
+        builder.vertex( transform, x, y + height, z ).color( r, g, b, 1.0f ).uv( u * TEX_SCALE, (v + textureHeight) * TEX_SCALE ).uv2( light ).endVertex();
+        builder.vertex( transform, x + width, y + height, z ).color( r, g, b, 1.0f ).uv( (u + textureWidth) * TEX_SCALE, (v + textureHeight) * TEX_SCALE ).uv2( light ).endVertex();
+        builder.vertex( transform, x + width, y, z ).color( r, g, b, 1.0f ).uv( (u + textureWidth) * TEX_SCALE, v * TEX_SCALE ).uv2( light ).endVertex();
+        builder.vertex( transform, x, y, z ).color( r, g, b, 1.0f ).uv( u * TEX_SCALE, v * TEX_SCALE ).uv2( light ).endVertex();
     }
 }

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

@@ -3,30 +3,36 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.client.render;
 
 import com.mojang.blaze3d.vertex.PoseStack;
 import com.mojang.math.Vector3f;
 import dan200.computercraft.fabric.mixin.ItemInHandRendererAccess;
-import net.fabricmc.api.EnvType;
-import net.fabricmc.api.Environment;
 import net.minecraft.client.Minecraft;
 import net.minecraft.client.renderer.ItemInHandRenderer;
 import net.minecraft.client.renderer.MultiBufferSource;
+import net.minecraft.client.renderer.block.model.ItemTransforms;
 import net.minecraft.util.Mth;
 import net.minecraft.world.InteractionHand;
 import net.minecraft.world.entity.HumanoidArm;
+import net.minecraft.world.entity.LivingEntity;
 import net.minecraft.world.entity.player.Player;
 import net.minecraft.world.item.ItemStack;
 
-@Environment( EnvType.CLIENT )
 public abstract class ItemMapLikeRenderer
 {
-    public void renderItemFirstPerson(
-        PoseStack transform, MultiBufferSource render, int lightTexture, InteractionHand hand, float pitch, float equipProgress,
-        float swingProgress, ItemStack stack
-    )
+    /**
+     * The main rendering method for the item.
+     *
+     * @param transform The matrix transformation stack
+     * @param render    The buffer to render to
+     * @param stack     The stack to render
+     * @param light     The packed lightmap coordinates.
+     * @see ItemInHandRenderer#renderItem(LivingEntity, ItemStack, ItemTransforms.TransformType, boolean, PoseStack, MultiBufferSource, int)
+     */
+    protected abstract void renderItem( PoseStack transform, MultiBufferSource render, ItemStack stack, int light );
+
+    public void renderItemFirstPerson( PoseStack transform, MultiBufferSource render, int lightTexture, InteractionHand hand, float pitch, float equipProgress, float swingProgress, ItemStack stack )
     {
         Player player = Minecraft.getInstance().player;
 
@@ -37,17 +43,60 @@ public abstract class ItemMapLikeRenderer
         }
         else
         {
-            renderItemFirstPersonSide( transform,
-                render,
-                lightTexture,
+            renderItemFirstPersonSide(
+                transform, render, lightTexture,
                 hand == InteractionHand.MAIN_HAND ? player.getMainArm() : player.getMainArm().getOpposite(),
-                equipProgress,
-                swingProgress,
-                stack );
+                equipProgress, swingProgress, stack
+            );
         }
         transform.popPose();
     }
 
+    /**
+     * Renders the item to one side of the player.
+     *
+     * @param transform     The matrix transformation stack
+     * @param render        The buffer to render to
+     * @param combinedLight The current light level
+     * @param side          The side to render on
+     * @param equipProgress The equip progress of this item
+     * @param swingProgress The swing progress of this item
+     * @param stack         The stack to render
+     * @see ItemInHandRenderer#renderOneHandedMap(PoseStack, MultiBufferSource, int, float, HumanoidArm, float, ItemStack)
+     */
+    private void renderItemFirstPersonSide( PoseStack transform, MultiBufferSource render, int combinedLight, HumanoidArm side, float equipProgress, float swingProgress, ItemStack stack )
+    {
+        Minecraft minecraft = Minecraft.getInstance();
+        float offset = side == HumanoidArm.RIGHT ? 1f : -1f;
+        transform.translate( offset * 0.125f, -0.125f, 0f );
+
+        // If the player is not invisible then render a single arm
+        if( !minecraft.player.isInvisible() )
+        {
+            transform.pushPose();
+            transform.mulPose( Vector3f.ZP.rotationDegrees( offset * 10f ) );
+            ((ItemInHandRendererAccess) minecraft.getItemInHandRenderer()).callRenderPlayerArm( transform, render, combinedLight, equipProgress, swingProgress, side );
+            transform.popPose();
+        }
+
+        // Setup the appropriate transformations. This is just copied from the
+        // corresponding method in ItemRenderer.
+        transform.pushPose();
+        transform.translate( offset * 0.51f, -0.08f + equipProgress * -1.2f, -0.75f );
+        float f1 = Mth.sqrt( swingProgress );
+        float f2 = Mth.sin( f1 * (float) Math.PI );
+        float f3 = -0.5f * f2;
+        float f4 = 0.4f * Mth.sin( f1 * ((float) Math.PI * 2f) );
+        float f5 = -0.3f * Mth.sin( swingProgress * (float) Math.PI );
+        transform.translate( offset * f3, f4 - 0.3f * f2, f5 );
+        transform.mulPose( Vector3f.XP.rotationDegrees( f2 * -45f ) );
+        transform.mulPose( Vector3f.YP.rotationDegrees( offset * f2 * -30f ) );
+
+        renderItem( transform, render, stack, combinedLight );
+
+        transform.popPose();
+    }
+
     /**
      * Render an item in the middle of the screen.
      *
@@ -58,9 +107,9 @@ 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 ItemInHandRenderer#renderTwoHandedMap(PoseStack, MultiBufferSource, int, float, float, float)
      */
-    private void renderItemFirstPersonCenter( PoseStack transform, MultiBufferSource render, int combinedLight, float pitch, float equipProgress,
-                                              float swingProgress, ItemStack stack )
+    private void renderItemFirstPersonCenter( PoseStack transform, MultiBufferSource render, int combinedLight, float pitch, float equipProgress, float swingProgress, ItemStack stack )
     {
         Minecraft minecraft = Minecraft.getInstance();
         ItemInHandRenderer renderer = minecraft.getItemInHandRenderer();
@@ -91,60 +140,4 @@ public abstract class ItemMapLikeRenderer
 
         renderItem( transform, render, stack, combinedLight );
     }
-
-    /**
-     * Renders the item to one side of the player.
-     *
-     * @param transform     The matrix transformation stack
-     * @param render        The buffer to render to
-     * @param combinedLight The current light level
-     * @param side          The side to render on
-     * @param equipProgress The equip progress of this item
-     * @param swingProgress The swing progress of this item
-     * @param stack         The stack to render
-     */
-    private void renderItemFirstPersonSide( PoseStack transform, MultiBufferSource render, int combinedLight, HumanoidArm side, float equipProgress,
-                                            float swingProgress, ItemStack stack )
-    {
-        Minecraft minecraft = Minecraft.getInstance();
-        float offset = side == HumanoidArm.RIGHT ? 1f : -1f;
-        transform.translate( offset * 0.125f, -0.125f, 0f );
-
-        // If the player is not invisible then render a single arm
-        if( !minecraft.player.isInvisible() )
-        {
-            transform.pushPose();
-            transform.mulPose( Vector3f.ZP.rotationDegrees( offset * 10f ) );
-            ((ItemInHandRendererAccess) minecraft.getItemInHandRenderer())
-                .callRenderPlayerArm( transform, render, combinedLight, equipProgress, swingProgress, side );
-            transform.popPose();
-        }
-
-        // Setup the appropriate transformations. This is just copied from the
-        // corresponding method in ItemRenderer.
-        transform.pushPose();
-        transform.translate( offset * 0.51f, -0.08f + equipProgress * -1.2f, -0.75f );
-        float f1 = Mth.sqrt( swingProgress );
-        float f2 = Mth.sin( f1 * (float) Math.PI );
-        float f3 = -0.5f * f2;
-        float f4 = 0.4f * Mth.sin( f1 * ((float) Math.PI * 2f) );
-        float f5 = -0.3f * Mth.sin( swingProgress * (float) Math.PI );
-        transform.translate( offset * f3, f4 - 0.3f * f2, f5 );
-        transform.mulPose( Vector3f.XP.rotationDegrees( f2 * -45f ) );
-        transform.mulPose( Vector3f.YP.rotationDegrees( offset * f2 * -30f ) );
-
-        renderItem( transform, render, stack, combinedLight );
-
-        transform.popPose();
-    }
-
-    /**
-     * The main rendering method for the item.
-     *
-     * @param transform The matrix transformation stack
-     * @param render    The buffer to render to
-     * @param stack     The stack to render
-     * @param light     TODO rebase
-     */
-    protected abstract void renderItem( PoseStack transform, MultiBufferSource render, ItemStack stack, int light );
 }

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

@@ -3,10 +3,8 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.client.render;
 
-import com.mojang.blaze3d.systems.RenderSystem;
 import com.mojang.blaze3d.vertex.*;
 import com.mojang.math.Matrix4f;
 import com.mojang.math.Vector3f;
@@ -17,9 +15,7 @@ import dan200.computercraft.shared.computer.core.ClientComputer;
 import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.pocket.items.ItemPocketComputer;
 import dan200.computercraft.shared.util.Colour;
-import net.minecraft.client.Minecraft;
 import net.minecraft.client.renderer.MultiBufferSource;
-import net.minecraft.client.renderer.RenderType;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.item.ItemStack;
 
@@ -39,7 +35,7 @@ public final class ItemPocketRenderer extends ItemMapLikeRenderer
     }
 
     @Override
-    protected void renderItem( PoseStack transform, MultiBufferSource render, ItemStack stack, int light )
+    protected void renderItem( PoseStack transform, MultiBufferSource renderer, ItemStack stack, int light )
     {
         ClientComputer computer = ItemPocketComputer.createClientComputer( stack );
         Terminal terminal = computer == null ? null : computer.getTerminal();
@@ -67,7 +63,7 @@ public final class ItemPocketRenderer extends ItemMapLikeRenderer
         transform.scale( 0.5f, 0.5f, 0.5f );
 
         float scale = 0.75f / Math.max( width + BORDER * 2, height + BORDER * 2 + LIGHT_HEIGHT );
-        transform.scale( scale, scale, 0 );
+        transform.scale( scale, scale, -1.0f );
         transform.translate( -0.5 * width, -0.5 * height, 0 );
 
         // Render the main frame
@@ -75,26 +71,21 @@ public final class ItemPocketRenderer extends ItemMapLikeRenderer
         ComputerFamily family = item.getFamily();
         int frameColour = item.getColour( stack );
 
-        Matrix4f matrix = transform.last()
-            .pose();
-        renderFrame( matrix, render, family, frameColour, light, width, height );
+        Matrix4f matrix = transform.last().pose();
+        renderFrame( matrix, renderer, family, frameColour, light, width, height );
 
         // Render the light
         int lightColour = ItemPocketComputer.getLightState( stack );
-        if( lightColour == -1 )
-        {
-            lightColour = Colour.BLACK.getHex();
-        }
-        renderLight( matrix, lightColour, width, height );
+        if( lightColour == -1 ) lightColour = Colour.BLACK.getHex();
+        renderLight( matrix, renderer, lightColour, width, height );
 
         if( computer != null && terminal != null )
         {
             FixedWidthFontRenderer.drawTerminal(
-                matrix, render.getBuffer( RenderTypes.TERMINAL_WITHOUT_DEPTH ),
+                matrix, renderer.getBuffer( RenderTypes.TERMINAL_WITHOUT_DEPTH ),
                 MARGIN, MARGIN, terminal, !computer.isColour(), MARGIN, MARGIN, MARGIN, MARGIN
             );
-            FixedWidthFontRenderer.drawBlocker( transform.last().pose(), render, 0, 0, width, height );
-
+            FixedWidthFontRenderer.drawBlocker( transform.last().pose(), renderer, 0, 0, width, height );
         }
         else
         {
@@ -106,45 +97,26 @@ public final class ItemPocketRenderer extends ItemMapLikeRenderer
 
     private static void renderFrame( Matrix4f transform, MultiBufferSource render, ComputerFamily family, int colour, int light, int width, int height )
     {
-        RenderSystem.enableBlend();
-        Minecraft.getInstance()
-            .getTextureManager()
-            .bindForSetup( colour != -1 ? ComputerBorderRenderer.BACKGROUND_COLOUR : ComputerBorderRenderer.getTexture( family ) );
-
         ResourceLocation texture = colour != -1 ? ComputerBorderRenderer.BACKGROUND_COLOUR : ComputerBorderRenderer.getTexture( family );
 
         float r = ((colour >>> 16) & 0xFF) / 255.0f;
         float g = ((colour >>> 8) & 0xFF) / 255.0f;
         float b = (colour & 0xFF) / 255.0f;
 
-        ComputerBorderRenderer.render( transform, render.getBuffer( RenderType.text( texture ) ), 0, 0, 0, light, width, height, true, r, g, b );
+        ComputerBorderRenderer.render( transform, render.getBuffer( ComputerBorderRenderer.getRenderType( texture ) ), 0, 0, 0, light, width, height, true, r, g, b );
     }
 
-    private static void renderLight( Matrix4f transform, int colour, int width, int height )
+    private static void renderLight( Matrix4f transform, MultiBufferSource render, int colour, int width, int height )
     {
-        RenderSystem.disableTexture();
-
         float r = ((colour >>> 16) & 0xFF) / 255.0f;
         float g = ((colour >>> 8) & 0xFF) / 255.0f;
         float b = (colour & 0xFF) / 255.0f;
+        float z = 0.001f;
 
-        Tesselator tessellator = Tesselator.getInstance();
-        BufferBuilder buffer = tessellator.getBuilder();
-        buffer.begin( VertexFormat.Mode.QUADS, DefaultVertexFormat.POSITION_COLOR );
-        buffer.vertex( transform, width - LIGHT_HEIGHT * 2, height + LIGHT_HEIGHT + BORDER / 2.0f, 0 )
-            .color( r, g, b, 1.0f )
-            .endVertex();
-        buffer.vertex( transform, width, height + LIGHT_HEIGHT + BORDER / 2.0f, 0 )
-            .color( r, g, b, 1.0f )
-            .endVertex();
-        buffer.vertex( transform, width, height + BORDER / 2.0f, 0 )
-            .color( r, g, b, 1.0f )
-            .endVertex();
-        buffer.vertex( transform, width - LIGHT_HEIGHT * 2, height + BORDER / 2.0f, 0 )
-            .color( r, g, b, 1.0f )
-            .endVertex();
-
-        tessellator.end();
-        RenderSystem.enableTexture();
+        VertexConsumer buffer = render.getBuffer( RenderTypes.POSITION_COLOR );
+        buffer.vertex( transform, width - LIGHT_HEIGHT * 2, height + LIGHT_HEIGHT + BORDER / 2.0f, z ).color( r, g, b, 1.0f ).endVertex();
+        buffer.vertex( transform, width, height + LIGHT_HEIGHT + BORDER / 2.0f, z ).color( r, g, b, 1.0f ).endVertex();
+        buffer.vertex( transform, width, height + BORDER / 2.0f, z ).color( r, g, b, 1.0f ).endVertex();
+        buffer.vertex( transform, width - LIGHT_HEIGHT * 2, height + BORDER / 2.0f, z ).color( r, g, b, 1.0f ).endVertex();
     }
 }

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

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.client.render;
 
 import com.mojang.blaze3d.vertex.PoseStack;
@@ -30,6 +29,21 @@ public final class ItemPrintoutRenderer extends ItemMapLikeRenderer
     {
     }
 
+    public boolean renderInFrame( PoseStack matrixStack, MultiBufferSource consumerProvider, ItemStack stack, int light )
+    {
+        if( !(stack.getItem() instanceof ItemPrintout) ) return false;
+
+        // Move a little bit forward to ensure we're not clipping with the frame
+        matrixStack.translate( 0.0f, 0.0f, -0.001f );
+        matrixStack.mulPose( Vector3f.ZP.rotationDegrees( 180f ) );
+        matrixStack.scale( 0.95f, 0.95f, -0.95f );
+        matrixStack.translate( -0.5f, -0.5f, 0.0f );
+
+        drawPrintout( matrixStack, consumerProvider, stack, light );
+
+        return true;
+    }
+
     @Override
     protected void renderItem( PoseStack transform, MultiBufferSource render, ItemStack stack, int light )
     {
@@ -49,10 +63,7 @@ public final class ItemPrintoutRenderer extends ItemMapLikeRenderer
         double height = LINES_PER_PAGE * FONT_HEIGHT + Y_TEXT_MARGIN * 2;
 
         // Non-books will be left aligned
-        if( !book )
-        {
-            width += offsetAt( pages );
-        }
+        if( !book ) width += offsetAt( pages );
 
         double visualWidth = width, visualHeight = height;
 
@@ -70,27 +81,11 @@ public final class ItemPrintoutRenderer extends ItemMapLikeRenderer
         transform.scale( scale, scale, scale );
         transform.translate( (max - width) / 2.0, (max - height) / 2.0, 0.0 );
 
-        Matrix4f matrix = transform.last()
-            .pose();
+        Matrix4f matrix = transform.last().pose();
         drawBorder( matrix, render, 0, 0, -0.01f, 0, pages, book, light );
-        drawText( matrix, render, X_TEXT_MARGIN, Y_TEXT_MARGIN, 0, light, ItemPrintout.getText( stack ), ItemPrintout.getColours( stack ) );
-    }
-
-    public boolean renderInFrame( PoseStack matrixStack, MultiBufferSource consumerProvider, ItemStack stack, int light )
-    {
-        if( !(stack.getItem() instanceof ItemPrintout) )
-        {
-            return false;
-        }
-
-        // Move a little bit forward to ensure we're not clipping with the frame
-        matrixStack.translate( 0.0f, 0.0f, -0.001f );
-        matrixStack.mulPose( Vector3f.ZP.rotationDegrees( 180f ) );
-        matrixStack.scale( 0.95f, 0.95f, -0.95f );
-        matrixStack.translate( -0.5f, -0.5f, 0.0f );
-
-        drawPrintout( matrixStack, consumerProvider, stack, light );
-
-        return true;
+        drawText(
+            matrix, render, X_TEXT_MARGIN, Y_TEXT_MARGIN, 0, light,
+            ItemPrintout.getText( stack ), ItemPrintout.getColours( stack )
+        );
     }
 }

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

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.client.render;
 
 import com.mojang.blaze3d.vertex.PoseStack;
@@ -27,8 +26,8 @@ import java.util.EnumSet;
 import static net.minecraft.core.Direction.*;
 
 /**
- * Overrides monitor highlighting to only render the outline of the <em>whole</em> monitor, rather than the current block. This means you do not get an
- * intrusive outline on top of the screen.
+ * Overrides monitor highlighting to only render the outline of the <em>whole</em> monitor, rather than the current
+ * block. This means you do not get an intrusive outline on top of the screen.
  */
 @Environment( EnvType.CLIENT )
 public final class MonitorHighlightRenderer
@@ -37,115 +36,62 @@ public final class MonitorHighlightRenderer
     {
     }
 
-    public static boolean drawHighlight( PoseStack matrixStack, VertexConsumer vertexConsumer, Entity entity, double d, double e, double f, BlockPos pos, BlockState blockState )
+    public static boolean drawHighlight( PoseStack transformStack, VertexConsumer buffer, Entity entity, double d, double e, double f, BlockPos pos, BlockState blockState )
     {
         // Preserve normal behaviour when crouching.
-        if( entity.isCrouching() )
-        {
-            return false;
-        }
+        if( entity.isCrouching() ) return false;
 
         Level world = entity.getCommandSenderWorld();
 
         BlockEntity tile = world.getBlockEntity( pos );
-        if( !(tile instanceof TileMonitor monitor) )
-        {
-            return false;
-        }
+        if( !(tile instanceof TileMonitor monitor) ) return false;
 
         // Determine which sides are part of the external faces of the monitor, and so which need to be rendered.
         EnumSet<Direction> faces = EnumSet.allOf( Direction.class );
         Direction front = monitor.getFront();
         faces.remove( front );
-        if( monitor.getXIndex() != 0 )
-        {
-            faces.remove( monitor.getRight()
-                .getOpposite() );
-        }
-        if( monitor.getXIndex() != monitor.getWidth() - 1 )
-        {
-            faces.remove( monitor.getRight() );
-        }
-        if( monitor.getYIndex() != 0 )
-        {
-            faces.remove( monitor.getDown()
-                .getOpposite() );
-        }
-        if( monitor.getYIndex() != monitor.getHeight() - 1 )
-        {
-            faces.remove( monitor.getDown() );
-        }
+        if( monitor.getXIndex() != 0 ) faces.remove( monitor.getRight().getOpposite() );
+        if( monitor.getXIndex() != monitor.getWidth() - 1 ) faces.remove( monitor.getRight() );
+        if( monitor.getYIndex() != 0 ) faces.remove( monitor.getDown().getOpposite() );
+        if( monitor.getYIndex() != monitor.getHeight() - 1 ) faces.remove( monitor.getDown() );
 
-        Vec3 cameraPos = Minecraft.getInstance().gameRenderer.getMainCamera()
-            .getPosition();
-        matrixStack.pushPose();
-        matrixStack.translate( pos.getX() - cameraPos.x(), pos.getY() - cameraPos.y(), pos.getZ() - cameraPos.z() );
+        Vec3 cameraPos = Minecraft.getInstance().gameRenderer.getMainCamera().getPosition();
+        transformStack.pushPose();
+        transformStack.translate( pos.getX() - cameraPos.x(), pos.getY() - cameraPos.y(), pos.getZ() - cameraPos.z() );
 
         // I wish I could think of a better way to do this
-        Matrix4f transform = matrixStack.last()
-            .pose();
-        Matrix3f normal = matrixStack.last().normal();
-        if( faces.contains( NORTH ) || faces.contains( WEST ) )
-        {
-            line( vertexConsumer, transform, normal, 0, 0, 0, UP );
-        }
-        if( faces.contains( SOUTH ) || faces.contains( WEST ) )
-        {
-            line( vertexConsumer, transform, normal, 0, 0, 1, UP );
-        }
-        if( faces.contains( NORTH ) || faces.contains( EAST ) )
-        {
-            line( vertexConsumer, transform, normal, 1, 0, 0, UP );
-        }
-        if( faces.contains( SOUTH ) || faces.contains( EAST ) )
-        {
-            line( vertexConsumer, transform, normal, 1, 0, 1, UP );
-        }
-        if( faces.contains( NORTH ) || faces.contains( DOWN ) )
-        {
-            line( vertexConsumer, transform, normal, 0, 0, 0, EAST );
-        }
-        if( faces.contains( SOUTH ) || faces.contains( DOWN ) )
-        {
-            line( vertexConsumer, transform, normal, 0, 0, 1, EAST );
-        }
-        if( faces.contains( NORTH ) || faces.contains( UP ) )
-        {
-            line( vertexConsumer, transform, normal, 0, 1, 0, EAST );
-        }
-        if( faces.contains( SOUTH ) || faces.contains( UP ) )
-        {
-            line( vertexConsumer, transform, normal, 0, 1, 1, EAST );
-        }
-        if( faces.contains( WEST ) || faces.contains( DOWN ) )
-        {
-            line( vertexConsumer, transform, normal, 0, 0, 0, SOUTH );
-        }
-        if( faces.contains( EAST ) || faces.contains( DOWN ) )
-        {
-            line( vertexConsumer, transform, normal, 1, 0, 0, SOUTH );
-        }
-        if( faces.contains( WEST ) || faces.contains( UP ) )
-        {
-            line( vertexConsumer, transform, normal, 0, 1, 0, SOUTH );
-        }
-        if( faces.contains( EAST ) || faces.contains( UP ) )
-        {
-            line( vertexConsumer, transform, normal, 1, 1, 0, SOUTH );
-        }
-
-        matrixStack.popPose();
+        Matrix4f transform = transformStack.last().pose();
+        Matrix3f normal = transformStack.last().normal();
+        if( faces.contains( NORTH ) || faces.contains( WEST ) ) line( buffer, transform, normal, 0, 0, 0, UP );
+        if( faces.contains( SOUTH ) || faces.contains( WEST ) ) line( buffer, transform, normal, 0, 0, 1, UP );
+        if( faces.contains( NORTH ) || faces.contains( EAST ) ) line( buffer, transform, normal, 1, 0, 0, UP );
+        if( faces.contains( SOUTH ) || faces.contains( EAST ) ) line( buffer, transform, normal, 1, 0, 1, UP );
+        if( faces.contains( NORTH ) || faces.contains( DOWN ) ) line( buffer, transform, normal, 0, 0, 0, EAST );
+        if( faces.contains( SOUTH ) || faces.contains( DOWN ) ) line( buffer, transform, normal, 0, 0, 1, EAST );
+        if( faces.contains( NORTH ) || faces.contains( UP ) ) line( buffer, transform, normal, 0, 1, 0, EAST );
+        if( faces.contains( SOUTH ) || faces.contains( UP ) ) line( buffer, transform, normal, 0, 1, 1, EAST );
+        if( faces.contains( WEST ) || faces.contains( DOWN ) ) line( buffer, transform, normal, 0, 0, 0, SOUTH );
+        if( faces.contains( EAST ) || faces.contains( DOWN ) ) line( buffer, transform, normal, 1, 0, 0, SOUTH );
+        if( faces.contains( WEST ) || faces.contains( UP ) ) line( buffer, transform, normal, 0, 1, 0, SOUTH );
+        if( faces.contains( EAST ) || faces.contains( UP ) ) line( buffer, transform, normal, 1, 1, 0, SOUTH );
 
+        transformStack.popPose();
         return true;
     }
 
     private static void line( VertexConsumer buffer, Matrix4f transform, Matrix3f normal, float x, float y, float z, Direction direction )
     {
-        buffer.vertex( transform, x, y, z )
+        buffer
+            .vertex( transform, x, y, z )
             .color( 0, 0, 0, 0.4f )
             .normal( normal, direction.getStepX(), direction.getStepY(), direction.getStepZ() )
             .endVertex();
-        buffer.vertex( transform, x + direction.getStepX(), y + direction.getStepY(), z + direction.getStepZ() )
+        buffer
+            .vertex( transform,
+                x + direction.getStepX(),
+                y + direction.getStepY(),
+                z + direction.getStepZ()
+            )
             .color( 0, 0, 0, 0.4f )
             .normal( normal, direction.getStepX(), direction.getStepY(), direction.getStepZ() )
             .endVertex();

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

@@ -29,13 +29,13 @@ public class MonitorTextureBufferShader extends ShaderInstance
     private final Uniform width;
     private final Uniform height;
 
-    public MonitorTextureBufferShader( ResourceProvider factory, String name, VertexFormat format ) throws IOException
+    public MonitorTextureBufferShader( ResourceProvider provider, String name, VertexFormat format ) throws IOException
     {
-        super( factory, name, format );
+        super( provider, name, format );
 
         width = getUniformChecked( "Width" );
         height = getUniformChecked( "Height" );
-        palette = new Uniform( "Palette", Uniform.UT_FLOAT3 /* UT_FLOAT3 */, 16 * 3, this );
+        palette = new Uniform( "Palette", Uniform.UT_FLOAT3, 16 * 3, this );
         updateUniformLocation( palette );
 
         Uniform tbo = getUniformChecked( "Tbo" );

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

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.client.render;
 
 import com.mojang.blaze3d.vertex.VertexConsumer;
@@ -18,31 +17,38 @@ import static dan200.computercraft.shared.media.items.ItemPrintout.LINES_PER_PAG
 
 public final class PrintoutRenderer
 {
+    private static final float BG_SIZE = 256.0f;
+
     /**
      * Width of a page.
      */
     public static final int X_SIZE = 172;
+
     /**
      * Height of a page.
      */
     public static final int Y_SIZE = 209;
+
     /**
      * Padding between the left and right of a page and the text.
      */
     public static final int X_TEXT_MARGIN = 13;
+
     /**
      * Padding between the top and bottom of a page and the text.
      */
     public static final int Y_TEXT_MARGIN = 11;
-    /**
-     * Size of the leather cover.
-     */
-    public static final int COVER_SIZE = 12;
-    private static final float BG_SIZE = 256.0f;
+
     /**
      * Width of the extra page texture.
      */
     private static final int X_FOLD_SIZE = 12;
+
+    /**
+     * Size of the leather cover.
+     */
+    public static final int COVER_SIZE = 12;
+
     private static final int COVER_Y = Y_SIZE;
     private static final int COVER_X = X_SIZE + 4 * X_FOLD_SIZE;
 
@@ -53,18 +59,11 @@ public final class PrintoutRenderer
         VertexConsumer buffer = renderer.getBuffer( RenderTypes.PRINTOUT_TEXT );
         for( int line = 0; line < LINES_PER_PAGE && line < text.length; line++ )
         {
-            FixedWidthFontRenderer.drawString( transform,
-                buffer,
-                x,
-                y + line * FONT_HEIGHT,
-                text[start + line],
-                colours[start + line],
-                null,
-                Palette.DEFAULT,
-                false,
-                0,
-                0,
-                light );
+            FixedWidthFontRenderer.drawString( transform, buffer,
+                x, y + line * FONT_HEIGHT, text[start + line], colours[start + line], null, Palette.DEFAULT,
+                false, 0, 0,
+                light
+            );
         }
     }
 
@@ -73,18 +72,12 @@ public final class PrintoutRenderer
         VertexConsumer buffer = renderer.getBuffer( RenderTypes.PRINTOUT_TEXT );
         for( int line = 0; line < LINES_PER_PAGE && line < text.length; line++ )
         {
-            FixedWidthFontRenderer.drawString( transform,
-                buffer,
-                x,
-                y + line * FONT_HEIGHT,
-                new TextBuffer( text[start + line] ),
-                new TextBuffer( colours[start + line] ),
-                null,
-                Palette.DEFAULT,
-                false,
-                0,
-                0,
-                light );
+            FixedWidthFontRenderer.drawString( transform, buffer,
+                x, y + line * FONT_HEIGHT,
+                new TextBuffer( text[start + line] ), new TextBuffer( colours[start + line] ),
+                null, Palette.DEFAULT, false, 0, 0,
+                light
+            );
         }
     }
 
@@ -107,18 +100,11 @@ public final class PrintoutRenderer
             drawTexture( transform, buffer, right, y - 8, z - 0.02f, COVER_X + COVER_SIZE, 0, COVER_SIZE, Y_SIZE + COVER_SIZE * 2, light );
 
             // Draw centre panel (just stretched texture, sorry).
-            drawTexture( transform,
-                buffer,
-                x - offset,
-                y,
-                z - 0.02f,
-                X_SIZE + offset * 2,
-                Y_SIZE,
-                COVER_X + COVER_SIZE / 2.0f,
-                COVER_SIZE,
-                COVER_SIZE,
-                Y_SIZE,
-                light );
+            drawTexture( transform, buffer,
+                x - offset, y, z - 0.02f, X_SIZE + offset * 2, Y_SIZE,
+                COVER_X + COVER_SIZE / 2.0f, COVER_SIZE, COVER_SIZE, Y_SIZE,
+                light
+            );
 
             float borderX = left;
             while( borderX < right )
@@ -134,26 +120,27 @@ public final class PrintoutRenderer
         drawTexture( transform, buffer, x, y, z, X_FOLD_SIZE * 2, 0, X_SIZE / 2.0f, Y_SIZE, light );
         for( int n = 0; n <= leftPages; n++ )
         {
-            drawTexture( transform, buffer, x - offsetAt( n ), y, z - 1e-3f * n,
+            drawTexture( transform, buffer,
+                x - offsetAt( n ), y, z - 1e-3f * n,
                 // Use the left "bold" fold for the outermost page
-                n == leftPages ? 0 : X_FOLD_SIZE, 0, X_FOLD_SIZE, Y_SIZE, light );
+                n == leftPages ? 0 : X_FOLD_SIZE, 0,
+                X_FOLD_SIZE, Y_SIZE, light
+            );
         }
 
         // Right half
         drawTexture( transform, buffer, x + X_SIZE / 2.0f, y, z, X_FOLD_SIZE * 2 + X_SIZE / 2.0f, 0, X_SIZE / 2.0f, Y_SIZE, light );
         for( int n = 0; n <= rightPages; n++ )
         {
-            drawTexture( transform, buffer, x + (X_SIZE - X_FOLD_SIZE) + offsetAt( n ), y, z - 1e-3f * n,
+            drawTexture( transform, buffer,
+                x + (X_SIZE - X_FOLD_SIZE) + offsetAt( n ), y, z - 1e-3f * n,
                 // Two folds, then the main page. Use the right "bold" fold for the outermost page.
-                X_FOLD_SIZE * 2 + X_SIZE + (n == rightPages ? X_FOLD_SIZE : 0), 0, X_FOLD_SIZE, Y_SIZE, light );
+                X_FOLD_SIZE * 2 + X_SIZE + (n == rightPages ? X_FOLD_SIZE : 0), 0,
+                X_FOLD_SIZE, Y_SIZE, light
+            );
         }
     }
 
-    public static float offsetAt( int page )
-    {
-        return (float) (32 * (1 - Math.pow( 1.2, -page )));
-    }
-
     private static void drawTexture( Matrix4f matrix, VertexConsumer buffer, float x, float y, float z, float u, float v, float width, float height, int light )
     {
         vertex( buffer, matrix, x, y + height, z, u / BG_SIZE, (v + height) / BG_SIZE, light );
@@ -162,8 +149,7 @@ public final class PrintoutRenderer
         vertex( buffer, matrix, x, y, z, u / BG_SIZE, v / BG_SIZE, light );
     }
 
-    private static void drawTexture( Matrix4f matrix, VertexConsumer buffer, float x, float y, float z, float width, float height, float u, float v,
-                                     float tWidth, float tHeight, int light )
+    private static void drawTexture( Matrix4f matrix, VertexConsumer buffer, float x, float y, float z, float width, float height, float u, float v, float tWidth, float tHeight, int light )
     {
         vertex( buffer, matrix, x, y + height, z, u / BG_SIZE, (v + tHeight) / BG_SIZE, light );
         vertex( buffer, matrix, x + width, y + height, z, (u + tWidth) / BG_SIZE, (v + tHeight) / BG_SIZE, light );
@@ -175,4 +161,9 @@ public final class PrintoutRenderer
     {
         buffer.vertex( matrix, x, y, z ).color( 255, 255, 255, 255 ).uv( u, v ).uv2( light ).endVertex();
     }
+
+    public static float offsetAt( int page )
+    {
+        return (float) (32 * (1 - Math.pow( 1.2, -page )));
+    }
 }

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

@@ -14,25 +14,26 @@ import net.minecraft.client.renderer.ShaderInstance;
 import net.minecraft.resources.ResourceLocation;
 
 import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
 
 public class RenderTypes
 {
-
     public static final int FULL_BRIGHT_LIGHTMAP = (0xF << 4) | (0xF << 20);
 
-    @Nullable
     public static MonitorTextureBufferShader monitorTboShader;
-
-    @Nullable
     public static ShaderInstance terminalShader;
 
     public static final RenderType TERMINAL_WITHOUT_DEPTH = Types.TERMINAL_WITHOUT_DEPTH;
-    public static final RenderType MONITOR_TBO = Types.MONITOR_TBO;
-    public static final RenderType TERMINAL_BLOCKER = Types.BLOCKER;
+    public static final RenderType TERMINAL_BLOCKER = Types.TERMINAL_BLOCKER;
     public static final RenderType TERMINAL_WITH_DEPTH = Types.TERMINAL_WITH_DEPTH;
+    public static final RenderType MONITOR_TBO = Types.MONITOR_TBO;
     public static final RenderType PRINTOUT_TEXT = Types.PRINTOUT_TEXT;
 
+    /**
+     * This looks wrong (it should be POSITION_COLOR_TEX_LIGHTMAP surely!) but the fragment/vertex shader for that
+     * appear to entirely ignore the lightmap.
+     *
+     * Note that vanilla maps do the same, so this isn't unreasonable.
+     */
     public static final RenderType PRINTOUT_BACKGROUND = RenderType.text( new ResourceLocation( "computercraft", "textures/gui/printout.png" ) );
 
     public static final RenderType POSITION_COLOR = Types.POSITION_COLOR;
@@ -53,24 +54,26 @@ public class RenderTypes
 
     private static final class Types extends RenderStateShard
     {
-        private static final VertexFormat.Mode GL_MODE = VertexFormat.Mode.TRIANGLES;
-        private static final VertexFormat FORMAT = DefaultVertexFormat.POSITION_COLOR_TEX;
-        private static final ShaderStateShard TERM_SHADER = new ShaderStateShard( RenderTypes::getTerminalShader );
-
-        private static final RenderStateShard.TextureStateShard TERM_FONT_TEXTURE = new RenderStateShard.TextureStateShard(
+        private static final RenderStateShard.TextureStateShard TERM_FONT_TEXTURE = new TextureStateShard(
             FixedWidthFontRenderer.FONT,
             false, false // blur, minimap
         );
+        private static final VertexFormat TERM_FORMAT = DefaultVertexFormat.POSITION_COLOR_TEX;
+        private static final VertexFormat.Mode TERM_MODE = VertexFormat.Mode.TRIANGLES;
+        private static final ShaderStateShard TERM_SHADER = new ShaderStateShard( RenderTypes::getTerminalShader );
 
-        public static final RenderType MONITOR_TBO = RenderType.create( "monitor_tbo", DefaultVertexFormat.POSITION_TEX, VertexFormat.Mode.TRIANGLE_STRIP, 128, false, false, // useDelegate, needsSorting
+        static final RenderType MONITOR_TBO = RenderType.create(
+            "monitor_tbo", DefaultVertexFormat.POSITION_TEX, VertexFormat.Mode.TRIANGLE_STRIP, 128,
+            false, false, // useDelegate, needsSorting
             RenderType.CompositeState.builder()
-                .setTextureState( TERM_FONT_TEXTURE ) // blur, minimap
-                .setShaderState( new RenderStateShard.ShaderStateShard( RenderTypes::getMonitorTextureBufferShader ) )
-                .setWriteMaskState( RenderType.COLOR_DEPTH_WRITE )
-                .createCompositeState( false ) );
+                .setTextureState( TERM_FONT_TEXTURE )
+                .setShaderState( new ShaderStateShard( RenderTypes::getMonitorTextureBufferShader ) )
+                .setWriteMaskState( COLOR_WRITE )
+                .createCompositeState( false )
+        );
 
         static final RenderType TERMINAL_WITHOUT_DEPTH = RenderType.create(
-            "terminal_without_depth", FORMAT, GL_MODE, 1024,
+            "terminal_without_depth", TERM_FORMAT, TERM_MODE, 1024,
             false, false, // useDelegate, needsSorting
             RenderType.CompositeState.builder()
                 .setTextureState( TERM_FONT_TEXTURE )
@@ -79,15 +82,18 @@ public class RenderTypes
                 .createCompositeState( false )
         );
 
-        static final RenderType BLOCKER = RenderType.create( "terminal_blocker", FORMAT, GL_MODE, 256, false, false, // useDelegate, needsSorting
+        static final RenderType TERMINAL_BLOCKER = RenderType.create(
+            "terminal_blocker", TERM_FORMAT, TERM_MODE, 256,
+            false, false, // useDelegate, needsSorting
             RenderType.CompositeState.builder()
                 .setTextureState( TERM_FONT_TEXTURE )
                 .setShaderState( TERM_SHADER )
                 .setWriteMaskState( DEPTH_WRITE )
-                .createCompositeState( false ) );
+                .createCompositeState( false )
+        );
 
         static final RenderType TERMINAL_WITH_DEPTH = RenderType.create(
-            "terminal_with_depth", FORMAT, GL_MODE, 1024,
+            "terminal_with_depth", TERM_FORMAT, TERM_MODE, 1024,
             false, false, // useDelegate, needsSorting
             RenderType.CompositeState.builder()
                 .setTextureState( TERM_FONT_TEXTURE )
@@ -95,8 +101,11 @@ public class RenderTypes
                 .createCompositeState( false )
         );
 
+        /**
+         * A variant of {@link #TERMINAL_WITH_DEPTH} which uses the lightmap rather than rendering fullbright.
+         */
         static final RenderType PRINTOUT_TEXT = RenderType.create(
-            "printout_text", DefaultVertexFormat.POSITION_COLOR_TEX_LIGHTMAP, GL_MODE, 1024,
+            "printout_text", DefaultVertexFormat.POSITION_COLOR_TEX_LIGHTMAP, TERM_MODE, 1024,
             false, false, // useDelegate, needsSorting
             RenderType.CompositeState.builder()
                 .setTextureState( TERM_FONT_TEXTURE )

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

@@ -3,10 +3,10 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.client.render;
 
 import com.mojang.blaze3d.platform.GlStateManager;
+import com.mojang.blaze3d.platform.MemoryTracker;
 import com.mojang.blaze3d.systems.RenderSystem;
 import com.mojang.blaze3d.vertex.*;
 import com.mojang.math.Matrix4f;
@@ -35,27 +35,25 @@ import org.lwjgl.opengl.GL31;
 import javax.annotation.Nonnull;
 import java.nio.ByteBuffer;
 
-import static com.mojang.blaze3d.platform.MemoryTracker.create;
 import static dan200.computercraft.client.gui.FixedWidthFontRenderer.*;
 
 public class TileEntityMonitorRenderer implements BlockEntityRenderer<TileMonitor>
 {
     /**
-     * {@link TileMonitor#RENDER_MARGIN}, but a tiny bit of additional padding to ensure that there is no space between the monitor frame and contents.
+     * {@link TileMonitor#RENDER_MARGIN}, but a tiny bit of additional padding to ensure that there is no space between
+     * the monitor frame and contents.
      */
     private static final float MARGIN = (float) (TileMonitor.RENDER_MARGIN * 1.1);
-    private static final Matrix4f IDENTITY = Transformation.identity()
-        .getMatrix();
     private static ByteBuffer tboContents;
 
+    private static final Matrix4f IDENTITY = Transformation.identity().getMatrix();
+
     public TileEntityMonitorRenderer( BlockEntityRendererProvider.Context context )
     {
-        // super( context );
     }
 
     @Override
-    public void render( @Nonnull TileMonitor monitor, float partialTicks, @Nonnull PoseStack transform, @Nonnull MultiBufferSource renderer,
-                        int lightmapCoord, int overlayLight )
+    public void render( @Nonnull TileMonitor monitor, float partialTicks, @Nonnull PoseStack transform, @Nonnull MultiBufferSource renderer, int lightmapCoord, int overlayLight )
     {
         // Render from the origin monitor
         ClientMonitor originTerminal = monitor.getClientMonitor();
@@ -86,15 +84,19 @@ public class TileEntityMonitorRenderer implements BlockEntityRenderer<TileMonito
 
         // Setup initial transform
         transform.pushPose();
-        transform.translate( originPos.getX() - monitorPos.getX() + 0.5,
+        transform.translate(
+            originPos.getX() - monitorPos.getX() + 0.5,
             originPos.getY() - monitorPos.getY() + 0.5,
-            originPos.getZ() - monitorPos.getZ() + 0.5 );
+            originPos.getZ() - monitorPos.getZ() + 0.5
+        );
 
         transform.mulPose( Vector3f.YN.rotationDegrees( yaw ) );
         transform.mulPose( Vector3f.XP.rotationDegrees( pitch ) );
-        transform.translate( -0.5 + TileMonitor.RENDER_BORDER + TileMonitor.RENDER_MARGIN,
+        transform.translate(
+            -0.5 + TileMonitor.RENDER_BORDER + TileMonitor.RENDER_MARGIN,
             origin.getHeight() - 0.5 - (TileMonitor.RENDER_BORDER + TileMonitor.RENDER_MARGIN) + 0,
-            0.50 );
+            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);
 
@@ -116,58 +118,56 @@ public class TileEntityMonitorRenderer implements BlockEntityRenderer<TileMonito
 
             // We don't draw the cursor with the VBO, as it's dynamic and so we'll end up refreshing far more than is
             // reasonable.
-            FixedWidthFontRenderer.drawCursor( matrix, renderer.getBuffer( RenderTypes.TERMINAL_WITHOUT_DEPTH ), 0, 0, terminal, !originTerminal.isColour() );
+            FixedWidthFontRenderer.drawCursor(
+                matrix, renderer.getBuffer( RenderTypes.TERMINAL_WITHOUT_DEPTH ),
+                0, 0, terminal, !originTerminal.isColour()
+            );
 
             transform.popPose();
 
-            // Draw the background blocker
             FixedWidthFontRenderer.drawBlocker(
                 transform.last().pose(), renderer,
                 -MARGIN, MARGIN,
                 (float) (xSize + 2 * MARGIN), (float) -(ySize + MARGIN * 2)
             );
 
+            // Force a flush of the blocker. WorldRenderer.updateCameraAndRender will "finish" all the built-in
+            // buffers before calling renderer.finish, which means the blocker isn't actually rendered at that point!
             renderer.getBuffer( RenderType.solid() );
         }
         else
         {
-            FixedWidthFontRenderer.drawEmptyTerminal( transform.last()
-                    .pose(),
-                renderer,
-                -MARGIN,
-                MARGIN,
-                (float) (xSize + 2 * MARGIN),
-                (float) -(ySize + MARGIN * 2) );
+            FixedWidthFontRenderer.drawEmptyTerminal(
+                transform.last().pose(), renderer,
+                -MARGIN, MARGIN,
+                (float) (xSize + 2 * MARGIN), (float) -(ySize + MARGIN * 2)
+            );
         }
 
         transform.popPose();
     }
 
-    private static void renderTerminal( MultiBufferSource renderer, Matrix4f matrix, ClientMonitor monitor, float xMargin, float yMargin )
+    private static void renderTerminal( @Nonnull MultiBufferSource renderer, Matrix4f matrix, ClientMonitor monitor, float xMargin, float yMargin )
     {
         Terminal terminal = monitor.getTerminal();
 
         MonitorRenderer renderType = MonitorRenderer.current();
         boolean redraw = monitor.pollTerminalChanged();
-        if( monitor.createBuffer( renderType ) )
-        {
-            redraw = true;
-        }
+        if( monitor.createBuffer( renderType ) ) redraw = true;
 
         switch( renderType )
         {
             case TBO:
             {
-
                 int width = terminal.getWidth(), height = terminal.getHeight();
-                int pixelWidth = width * FONT_WIDTH, pixelHeight = height * FONT_HEIGHT;
 
+                int pixelWidth = width * FONT_WIDTH, pixelHeight = height * FONT_HEIGHT;
                 if( redraw )
                 {
                     int size = width * height * 3;
                     if( tboContents == null || tboContents.capacity() < size )
                     {
-                        tboContents = create( size );
+                        tboContents = MemoryTracker.create( size );
                     }
 
                     ByteBuffer monitorBuffer = tboContents;
@@ -204,37 +204,34 @@ public class TileEntityMonitorRenderer implements BlockEntityRenderer<TileMonito
                 tboVertex( buffer, matrix, pixelWidth + xMargin, -yMargin );
                 tboVertex( buffer, matrix, pixelWidth + xMargin, pixelHeight + yMargin );
 
+                // And force things to flush. We strictly speaking do this later on anyway for the cursor, but nice to
+                // be consistent.
                 renderer.getBuffer( RenderTypes.TERMINAL_WITHOUT_DEPTH );
                 break;
             }
 
             case VBO:
+            {
                 VertexBuffer vbo = monitor.buffer;
                 if( redraw )
                 {
                     Tesselator tessellator = Tesselator.getInstance();
                     BufferBuilder builder = tessellator.getBuilder();
                     builder.begin( RenderTypes.TERMINAL_WITHOUT_DEPTH.mode(), RenderTypes.TERMINAL_WITHOUT_DEPTH.format() );
-                    FixedWidthFontRenderer.drawTerminalWithoutCursor( IDENTITY,
-                        builder,
-                        0,
-                        0,
-                        terminal,
-                        !monitor.isColour(),
-                        yMargin,
-                        yMargin,
-                        xMargin,
-                        xMargin );
+                    FixedWidthFontRenderer.drawTerminalWithoutCursor(
+                        IDENTITY, builder, 0, 0,
+                        terminal, !monitor.isColour(), yMargin, yMargin, xMargin, xMargin
+                    );
 
                     builder.end();
                     vbo.upload( builder );
                 }
 
                 renderer.getBuffer( RenderTypes.TERMINAL_WITHOUT_DEPTH );
-
                 RenderTypes.TERMINAL_WITHOUT_DEPTH.setupRenderState();
                 vbo.drawWithShader( matrix, RenderSystem.getProjectionMatrix(), RenderTypes.getTerminalShader() );
                 break;
+            }
         }
     }
 

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

@@ -47,7 +47,7 @@ public class TileEntityTurtleRenderer implements BlockEntityRenderer<TileTurtle>
 
     private final Random random = new Random( 0 );
 
-    BlockEntityRenderDispatcher renderer;
+    private final BlockEntityRenderDispatcher renderer;
 
     public TileEntityTurtleRenderer( BlockEntityRendererProvider.Context context )
     {
@@ -68,39 +68,28 @@ public class TileEntityTurtleRenderer implements BlockEntityRenderer<TileTurtle>
 
     public static ModelResourceLocation getTurtleOverlayModel( ResourceLocation overlay, boolean christmas )
     {
-        if( overlay != null )
-        {
-            return new ModelResourceLocation( overlay, "inventory" );
-        }
-        if( christmas )
-        {
-            return ELF_OVERLAY_MODEL;
-        }
+        if( overlay != null ) return new ModelResourceLocation( overlay, "inventory" );
+        if( christmas ) return ELF_OVERLAY_MODEL;
         return null;
     }
 
     @Override
-    public void render( @Nonnull TileTurtle turtle, float partialTicks, @Nonnull PoseStack transform, @Nonnull MultiBufferSource buffers,
-                        int lightmapCoord, int overlayLight )
+    public void render( @Nonnull TileTurtle turtle, float partialTicks, @Nonnull PoseStack transform, @Nonnull MultiBufferSource buffers, int lightmapCoord, int overlayLight )
     {
         // Render the label
-        String label = turtle.createProxy()
-            .getLabel();
+        String label = turtle.createProxy().getLabel();
         HitResult hit = renderer.cameraHitResult;
-        if( label != null && hit.getType() == HitResult.Type.BLOCK && turtle.getBlockPos()
-            .equals( ((BlockHitResult) hit).getBlockPos() ) )
+        if( label != null && hit.getType() == HitResult.Type.BLOCK && turtle.getBlockPos().equals( ((BlockHitResult) hit).getBlockPos() ) )
         {
             Minecraft mc = Minecraft.getInstance();
             Font font = mc.font;
 
             transform.pushPose();
             transform.translate( 0.5, 1.2, 0.5 );
-            transform.mulPose( mc.getEntityRenderDispatcher()
-                .cameraOrientation() );
+            transform.mulPose( mc.getEntityRenderDispatcher().cameraOrientation() );
             transform.scale( -0.025f, -0.025f, 0.025f );
 
-            Matrix4f matrix = transform.last()
-                .pose();
+            Matrix4f matrix = transform.last().pose();
             int opacity = (int) (mc.options.getBackgroundOpacity( 0.25f ) * 255) << 24;
             float width = -font.width( label ) / 2.0f;
             font.drawInBatch( label, width, (float) 0, 0x20ffffff, false, matrix, buffers, true, opacity, lightmapCoord );
@@ -147,14 +136,10 @@ public class TileEntityTurtleRenderer implements BlockEntityRenderer<TileTurtle>
         transform.popPose();
     }
 
-    private void renderUpgrade( @Nonnull PoseStack transform, @Nonnull VertexConsumer renderer, int lightmapCoord, int overlayLight, TileTurtle turtle,
-                                TurtleSide side, float f )
+    private void renderUpgrade( @Nonnull PoseStack transform, @Nonnull VertexConsumer renderer, int lightmapCoord, int overlayLight, TileTurtle turtle, TurtleSide side, float f )
     {
         ITurtleUpgrade upgrade = turtle.getUpgrade( side );
-        if( upgrade == null )
-        {
-            return;
-        }
+        if( upgrade == null ) return;
         transform.pushPose();
 
         float toolAngle = turtle.getToolRenderAngle( side, f );
@@ -170,18 +155,13 @@ public class TileEntityTurtleRenderer implements BlockEntityRenderer<TileTurtle>
         transform.popPose();
     }
 
-    private void renderModel( @Nonnull PoseStack transform, @Nonnull VertexConsumer renderer, int lightmapCoord, int overlayLight,
-                              ModelResourceLocation modelLocation, int[] tints )
+    private void renderModel( @Nonnull PoseStack transform, @Nonnull VertexConsumer renderer, int lightmapCoord, int overlayLight, ModelResourceLocation modelLocation, int[] tints )
     {
-        ModelManager modelManager = Minecraft.getInstance()
-            .getItemRenderer()
-            .getItemModelShaper()
-            .getModelManager();
+        ModelManager modelManager = Minecraft.getInstance().getItemRenderer().getItemModelShaper().getModelManager();
         renderModel( transform, renderer, lightmapCoord, overlayLight, modelManager.getModel( modelLocation ), tints );
     }
 
-    private void renderModel( @Nonnull PoseStack transform, @Nonnull VertexConsumer renderer, int lightmapCoord, int overlayLight, BakedModel model,
-                              int[] tints )
+    private void renderModel( @Nonnull PoseStack transform, @Nonnull VertexConsumer renderer, int lightmapCoord, int overlayLight, BakedModel model, int[] tints )
     {
         random.setSeed( 0 );
         renderQuads( transform, renderer, lightmapCoord, overlayLight, model.getQuads( null, null, random ), tints );
@@ -191,8 +171,7 @@ public class TileEntityTurtleRenderer implements BlockEntityRenderer<TileTurtle>
         }
     }
 
-    private static void renderQuads( @Nonnull PoseStack transform, @Nonnull VertexConsumer buffer, int lightmapCoord, int overlayLight,
-                                     List<BakedQuad> quads, int[] tints )
+    private static void renderQuads( @Nonnull PoseStack transform, @Nonnull VertexConsumer buffer, int lightmapCoord, int overlayLight, List<BakedQuad> quads, int[] tints )
     {
         PoseStack.Pose matrix = transform.last();
 
@@ -202,10 +181,7 @@ public class TileEntityTurtleRenderer implements BlockEntityRenderer<TileTurtle>
             if( tints != null && bakedquad.isTinted() )
             {
                 int idx = bakedquad.getTintIndex();
-                if( idx >= 0 && idx < tints.length )
-                {
-                    tint = tints[bakedquad.getTintIndex()];
-                }
+                if( idx >= 0 && idx < tints.length ) tint = tints[bakedquad.getTintIndex()];
             }
 
             float f = (float) (tint >> 16 & 255) / 255.0F;

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

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.client.render;
 
 import com.mojang.datafixers.util.Pair;

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

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.client.render;
 
 import com.mojang.math.Transformation;
@@ -32,8 +31,7 @@ public class TurtleMultiModel implements BakedModel
     private List<BakedQuad> generalQuads = null;
     private final Map<Direction, List<BakedQuad>> faceQuads = new EnumMap<>( Direction.class );
 
-    public TurtleMultiModel( BakedModel baseModel, BakedModel overlayModel, Transformation generalTransform, TransformedModel leftUpgradeModel,
-                             TransformedModel rightUpgradeModel )
+    public TurtleMultiModel( BakedModel baseModel, BakedModel overlayModel, Transformation generalTransform, TransformedModel leftUpgradeModel, TransformedModel rightUpgradeModel )
     {
         // Get the models
         this.baseModel = baseModel;
@@ -45,22 +43,17 @@ public class TurtleMultiModel implements BakedModel
 
     @Nonnull
     @Override
+    @Deprecated
     public List<BakedQuad> getQuads( BlockState state, Direction side, @Nonnull Random rand )
     {
         if( side != null )
         {
-            if( !faceQuads.containsKey( side ) )
-            {
-                faceQuads.put( side, buildQuads( state, side, rand ) );
-            }
+            if( !faceQuads.containsKey( side ) ) faceQuads.put( side, buildQuads( state, side, rand ) );
             return faceQuads.get( side );
         }
         else
         {
-            if( generalQuads == null )
-            {
-                generalQuads = buildQuads( state, side, rand );
-            }
+            if( generalQuads == null ) generalQuads = buildQuads( state, side, rand );
             return generalQuads;
         }
     }
@@ -70,24 +63,20 @@ public class TurtleMultiModel implements BakedModel
         ArrayList<BakedQuad> quads = new ArrayList<>();
 
 
-        ModelTransformer.transformQuadsTo( quads, baseModel.getQuads( state, side, rand ), generalTransform.getMatrix() );
+        transformQuadsTo( quads, baseModel.getQuads( state, side, rand ), generalTransform );
         if( overlayModel != null )
         {
-            ModelTransformer.transformQuadsTo( quads, overlayModel.getQuads( state, side, rand ), generalTransform.getMatrix() );
+            transformQuadsTo( quads, overlayModel.getQuads( state, side, rand ), generalTransform );
         }
         if( leftUpgradeModel != null )
         {
             Transformation upgradeTransform = generalTransform.compose( leftUpgradeModel.getMatrix() );
-            ModelTransformer.transformQuadsTo( quads, leftUpgradeModel.getModel()
-                    .getQuads( state, side, rand ),
-                upgradeTransform.getMatrix() );
+            transformQuadsTo( quads, leftUpgradeModel.getModel().getQuads( state, side, rand ), upgradeTransform );
         }
         if( rightUpgradeModel != null )
         {
             Transformation upgradeTransform = generalTransform.compose( rightUpgradeModel.getMatrix() );
-            ModelTransformer.transformQuadsTo( quads, rightUpgradeModel.getModel()
-                    .getQuads( state, side, rand ),
-                upgradeTransform.getMatrix() );
+            transformQuadsTo( quads, rightUpgradeModel.getModel().getQuads( state, side, rand ), upgradeTransform );
         }
         quads.trimToSize();
         return quads;
@@ -105,18 +94,18 @@ public class TurtleMultiModel implements BakedModel
         return baseModel.isGui3d();
     }
 
-    @Override
-    public boolean usesBlockLight()
-    {
-        return baseModel.usesBlockLight();
-    }
-
     @Override
     public boolean isCustomRenderer()
     {
         return baseModel.isCustomRenderer();
     }
 
+    @Override
+    public boolean usesBlockLight()
+    {
+        return baseModel.usesBlockLight();
+    }
+
     @Nonnull
     @Override
     @Deprecated
@@ -139,4 +128,9 @@ public class TurtleMultiModel implements BakedModel
     {
         return ItemOverrides.EMPTY;
     }
+
+    private void transformQuadsTo( List<BakedQuad> output, List<BakedQuad> quads, Transformation transform )
+    {
+        ModelTransformer.transformQuadsTo( output, quads, transform.getMatrix() );
+    }
 }

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

@@ -15,16 +15,10 @@ import net.minecraft.resources.ResourceLocation;
 import javax.annotation.Nonnull;
 
 public class TurtlePlayerRenderer extends EntityRenderer<TurtlePlayer>
-{ //FIXME Make sure this isn't an issue. Context was EntityRenderDispatcher.
-    public TurtlePlayerRenderer( EntityRendererProvider.Context context )
-    {
-        super( context );
-    }
-
-    @Override
-    public void render( @Nonnull TurtlePlayer entityIn, float entityYaw, float partialTicks, @Nonnull PoseStack transform,
-                        @Nonnull MultiBufferSource buffer, int packedLightIn )
+{
+    public TurtlePlayerRenderer( EntityRendererProvider.Context renderManager )
     {
+        super( renderManager );
     }
 
     @Nonnull
@@ -33,4 +27,9 @@ public class TurtlePlayerRenderer extends EntityRenderer<TurtlePlayer>
     {
         return ComputerBorderRenderer.BACKGROUND_NORMAL;
     }
+
+    @Override
+    public void render( @Nonnull TurtlePlayer entityIn, float entityYaw, float partialTicks, @Nonnull PoseStack transform, @Nonnull MultiBufferSource buffer, int packedLightIn )
+    {
+    }
 }

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

@@ -5,7 +5,6 @@
  */
 package dan200.computercraft.client.render;
 
-import com.google.common.base.Objects;
 import com.mojang.blaze3d.vertex.PoseStack;
 import com.mojang.math.Transformation;
 import dan200.computercraft.api.client.TransformedModel;
@@ -50,59 +49,18 @@ public class TurtleSmartItemModel implements BakedModel
         stack.translate( 0, 0, 1 );
 
         identity = Transformation.identity();
-        flip = new Transformation( stack.last()
-            .pose() );
+        flip = new Transformation( stack.last().pose() );
     }
 
-    private static class TurtleModelCombination
+    private static record TurtleModelCombination(
+        boolean colour,
+        ITurtleUpgrade leftUpgrade,
+        ITurtleUpgrade rightUpgrade,
+        ResourceLocation overlay,
+        boolean christmas,
+        boolean flip
+    )
     {
-        final boolean colour;
-        final ITurtleUpgrade leftUpgrade;
-        final ITurtleUpgrade rightUpgrade;
-        final ResourceLocation overlay;
-        final boolean christmas;
-        final boolean flip;
-
-        TurtleModelCombination( boolean colour, ITurtleUpgrade leftUpgrade, ITurtleUpgrade rightUpgrade, ResourceLocation overlay, boolean christmas,
-                                boolean flip )
-        {
-            this.colour = colour;
-            this.leftUpgrade = leftUpgrade;
-            this.rightUpgrade = rightUpgrade;
-            this.overlay = overlay;
-            this.christmas = christmas;
-            this.flip = flip;
-        }
-
-        @Override
-        public boolean equals( Object other )
-        {
-            if( other == this )
-            {
-                return true;
-            }
-            if( !(other instanceof TurtleModelCombination otherCombo) )
-            {
-                return false;
-            }
-
-            return otherCombo.colour == colour && otherCombo.leftUpgrade == leftUpgrade && otherCombo.rightUpgrade == rightUpgrade && Objects.equal(
-                otherCombo.overlay, overlay ) && otherCombo.christmas == christmas && otherCombo.flip == flip;
-        }
-
-        @Override
-        public int hashCode()
-        {
-            final int prime = 31;
-            int result = 0;
-            result = prime * result + (colour ? 1 : 0);
-            result = prime * result + (leftUpgrade != null ? leftUpgrade.hashCode() : 0);
-            result = prime * result + (rightUpgrade != null ? rightUpgrade.hashCode() : 0);
-            result = prime * result + (overlay != null ? overlay.hashCode() : 0);
-            result = prime * result + (christmas ? 1 : 0);
-            result = prime * result + (flip ? 1 : 0);
-            return result;
-        }
     }
 
     private final BakedModel familyModel;
@@ -121,7 +79,7 @@ public class TurtleSmartItemModel implements BakedModel
         {
             @Nonnull
             @Override
-            public BakedModel resolve( BakedModel originalModel, ItemStack stack, @Nullable ClientLevel world, @Nullable LivingEntity entity, int seed )
+            public BakedModel resolve( @Nonnull BakedModel originalModel, @Nonnull ItemStack stack, @Nullable ClientLevel world, @Nullable LivingEntity entity, int random )
             {
                 ItemTurtle turtle = (ItemTurtle) stack.getItem();
                 int colour = turtle.getColour( stack );
@@ -134,21 +92,23 @@ public class TurtleSmartItemModel implements BakedModel
                 TurtleModelCombination combo = new TurtleModelCombination( colour != -1, leftUpgrade, rightUpgrade, overlay, christmas, flip );
 
                 BakedModel model = cachedModels.get( combo );
-                if( model == null )
-                {
-                    cachedModels.put( combo, model = buildModel( combo ) );
-                }
+                if( model == null ) cachedModels.put( combo, model = buildModel( combo ) );
                 return model;
             }
         };
     }
 
+    @Nonnull
+    @Override
+    public ItemOverrides getOverrides()
+    {
+        return overrides;
+    }
+
     private BakedModel buildModel( TurtleModelCombination combo )
     {
         Minecraft mc = Minecraft.getInstance();
-        ModelManager modelManager = mc.getItemRenderer()
-            .getItemModelShaper()
-            .getModelManager();
+        ModelManager modelManager = mc.getItemRenderer().getItemModelShaper().getModelManager();
         ModelResourceLocation overlayModelLocation = TileEntityTurtleRenderer.getTurtleOverlayModel( combo.overlay, combo.christmas );
 
         BakedModel baseModel = combo.colour ? colourModel : familyModel;
@@ -179,12 +139,6 @@ public class TurtleSmartItemModel implements BakedModel
         return familyModel.isGui3d();
     }
 
-    @Override
-    public boolean usesBlockLight()
-    {
-        return familyModel.usesBlockLight();
-    }
-
     @Override
     public boolean isCustomRenderer()
     {
@@ -192,17 +146,17 @@ public class TurtleSmartItemModel implements BakedModel
     }
 
     @Override
-    @Deprecated
-    public TextureAtlasSprite getParticleIcon()
+    public boolean usesBlockLight()
     {
-        return familyModel.getParticleIcon();
+        return familyModel.usesBlockLight();
     }
 
     @Nonnull
     @Override
-    public ItemOverrides getOverrides()
+    @Deprecated
+    public TextureAtlasSprite getParticleIcon()
     {
-        return overrides;
+        return familyModel.getParticleIcon();
     }
 
     @Nonnull

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

@@ -484,7 +484,7 @@ public class FSAPI implements ILuaAPI
      *
      * This string is formatted like a normal path string, but can include any
      * number of wildcards ({@code *}) to look for files matching anything.
-     * For example, {@code rom/* /command*} will look for any path starting with
+     * For example, <code>rom/&#42;/command*</code> will look for any path starting with
      * {@code command} inside any subdirectory of {@code /rom}.
      *
      * @param path The wildcard-qualified path to search for.

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

@@ -17,6 +17,7 @@ import dan200.computercraft.core.asm.NamedMethod;
 import dan200.computercraft.core.asm.PeripheralMethod;
 import dan200.computercraft.core.computer.ComputerSide;
 import dan200.computercraft.core.tracking.TrackingField;
+import dan200.computercraft.shared.util.LuaUtil;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
@@ -36,6 +37,7 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
         private final IPeripheral peripheral;
 
         private final String type;
+        private final Set<String> additionalTypes;
         private final Map<String, PeripheralMethod> methodMap;
         private boolean attached;
 
@@ -47,6 +49,7 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
             attached = false;
 
             type = Objects.requireNonNull( peripheral.getType(), "Peripheral type cannot be null" );
+            additionalTypes = peripheral.getAdditionalTypes();
 
             methodMap = PeripheralAPI.getMethods( peripheral );
         }
@@ -61,6 +64,11 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
             return type;
         }
 
+        public Set<String> getAdditionalTypes()
+        {
+            return additionalTypes;
+        }
+
         public Collection<String> getMethods()
         {
             return methodMap.keySet();
@@ -298,7 +306,23 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
         synchronized( peripherals )
         {
             PeripheralWrapper p = peripherals[side.ordinal()];
-            if( p != null ) return new Object[] { p.getType() };
+            return p == null ? null : LuaUtil.consArray( p.getType(), p.getAdditionalTypes() );
+        }
+    }
+
+    @LuaFunction
+    public final Object[] hasType( String sideName, String type )
+    {
+        ComputerSide side = ComputerSide.valueOfInsensitive( sideName );
+        if( side == null ) return null;
+
+        synchronized( peripherals )
+        {
+            PeripheralWrapper p = peripherals[side.ordinal()];
+            if( p != null )
+            {
+                return new Object[] { p.getType().equals( type ) || p.getAdditionalTypes().contains( type ) };
+            }
         }
         return null;
     }

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

@@ -100,7 +100,7 @@ public class BinaryWritableHandle extends HandleGeneric
         try
         {
             // Technically this is not needed
-            if( writer instanceof FileChannel ) ((FileChannel) writer).force( false );
+            if( writer instanceof FileChannel channel ) channel.force( false );
         }
         catch( IOException ignored )
         {

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

@@ -153,7 +153,7 @@ public class WebsocketHandle implements Closeable
                 return MethodResult.of();
             }
             else if( event.length >= 2 && timeoutId != -1 && Objects.equal( event[0], TIMER_EVENT )
-                && event[1] instanceof Number && ((Number) event[1]).intValue() == timeoutId )
+                && event[1] instanceof Number id && id.intValue() == timeoutId )
             {
                 // If we received a matching timer event then abort.
                 return MethodResult.of();

src/main/java/dan200/computercraft/core/asm/Generator.java

@@ -130,8 +130,6 @@ public final class Generator<T>
 
     private void addMethod( List<NamedMethod<T>> methods, Method method, LuaFunction annotation, PeripheralType genericType, T instance )
     {
-        if( annotation.mainThread() ) instance = wrap.apply( instance );
-
         String[] names = annotation.value();
         boolean isSimple = method.getReturnType() != MethodResult.class && !annotation.mainThread();
         if( names.length == 0 )
@@ -183,6 +181,13 @@ public final class Generator<T>
             }
         }
 
+        LuaFunction annotation = method.getAnnotation( LuaFunction.class );
+        if( annotation.unsafe() && annotation.mainThread() )
+        {
+            ComputerCraft.log.error( "Lua Method {} cannot use unsafe and mainThread", name );
+            return Optional.empty();
+        }
+
         // We have some rather ugly handling of static methods in both here and the main generate function. Static methods
         // only come from generic sources, so this should be safe.
         Class<?> target = Modifier.isStatic( modifiers ) ? method.getParameterTypes()[0] : method.getDeclaringClass();
@@ -190,11 +195,13 @@ public final class Generator<T>
         try
         {
             String className = method.getDeclaringClass().getName() + "$cc$" + method.getName() + METHOD_ID.getAndIncrement();
-            byte[] bytes = generate( className, target, method );
+            byte[] bytes = generate( className, target, method, annotation.unsafe() );
             if( bytes == null ) return Optional.empty();
 
             Class<?> klass = DeclaringClassLoader.INSTANCE.define( className, bytes, method.getDeclaringClass().getProtectionDomain() );
-            return Optional.of( klass.asSubclass( base ).getDeclaredConstructor().newInstance() );
+
+            T instance = klass.asSubclass( base ).getDeclaredConstructor().newInstance();
+            return Optional.of( annotation.mainThread() ? wrap.apply( instance ) : instance );
         }
         catch( ReflectiveOperationException | ClassFormatError | RuntimeException e )
         {
@@ -205,7 +212,7 @@ public final class Generator<T>
     }
 
     @Nullable
-    private byte[] generate( String className, Class<?> target, Method method )
+    private byte[] generate( String className, Class<?> target, Method method, boolean unsafe )
     {
         String internalName = className.replace( ".", "/" );
 
@@ -238,7 +245,7 @@ public final class Generator<T>
             int argIndex = 0;
             for( java.lang.reflect.Type genericArg : method.getGenericParameterTypes() )
             {
-                Boolean loadedArg = loadArg( mw, target, method, genericArg, argIndex );
+                Boolean loadedArg = loadArg( mw, target, method, unsafe, genericArg, argIndex );
                 if( loadedArg == null ) return null;
                 if( loadedArg ) argIndex++;
             }
@@ -285,7 +292,7 @@ public final class Generator<T>
         return cw.toByteArray();
     }
 
-    private Boolean loadArg( MethodVisitor mw, Class<?> target, Method method, java.lang.reflect.Type genericArg, int argIndex )
+    private Boolean loadArg( MethodVisitor mw, Class<?> target, Method method, boolean unsafe, java.lang.reflect.Type genericArg, int argIndex )
     {
         if( genericArg == target )
         {
@@ -324,7 +331,7 @@ public final class Generator<T>
                 return true;
             }
 
-            String name = Reflect.getLuaName( Primitives.unwrap( klass ) );
+            String name = Reflect.getLuaName( Primitives.unwrap( klass ), unsafe );
             if( name != null )
             {
                 mw.visitVarInsn( ALOAD, 2 + context.size() );
@@ -344,7 +351,7 @@ public final class Generator<T>
             return true;
         }
 
-        String name = arg == Object.class ? "" : Reflect.getLuaName( arg );
+        String name = arg == Object.class ? "" : Reflect.getLuaName( arg, unsafe );
         if( name != null )
         {
             if( Reflect.getRawType( method, genericArg, false ) == null ) return null;

src/main/java/dan200/computercraft/core/asm/Reflect.java

@@ -6,6 +6,7 @@
 package dan200.computercraft.core.asm;
 
 import dan200.computercraft.ComputerCraft;
+import dan200.computercraft.api.lua.LuaTable;
 import org.objectweb.asm.MethodVisitor;
 
 import javax.annotation.Nullable;
@@ -25,7 +26,7 @@ final class Reflect
     }
 
     @Nullable
-    static String getLuaName( Class<?> klass )
+    static String getLuaName( Class<?> klass, boolean unsafe )
     {
         if( klass.isPrimitive() )
         {
@@ -39,6 +40,7 @@ final class Reflect
             if( klass == Map.class ) return "Table";
             if( klass == String.class ) return "String";
             if( klass == ByteBuffer.class ) return "Bytes";
+            if( klass == LuaTable.class && unsafe ) return "TableUnsafe";
         }
 
         return null;

src/main/java/dan200/computercraft/core/lua/BasicFunction.java

@@ -59,6 +59,10 @@ class BasicFunction extends VarArgFunction
             }
             throw new LuaError( "Java Exception Thrown: " + t, 0 );
         }
+        finally
+        {
+            arguments.releaseImmediate();
+        }
 
         if( results.getCallback() != null )
         {

src/main/java/dan200/computercraft/core/lua/CobaltLuaMachine.java

@@ -15,6 +15,7 @@ import dan200.computercraft.core.tracking.Tracking;
 import dan200.computercraft.core.tracking.TrackingField;
 import dan200.computercraft.shared.util.ThreadUtils;
 import org.squiddev.cobalt.*;
+import org.squiddev.cobalt.LuaTable;
 import org.squiddev.cobalt.compiler.CompileException;
 import org.squiddev.cobalt.compiler.LoadState;
 import org.squiddev.cobalt.debug.DebugFrame;

src/main/java/dan200/computercraft/core/lua/ResultInterpreterFunction.java

@@ -69,6 +69,10 @@ class ResultInterpreterFunction extends ResumableVarArgFunction<ResultInterprete
             }
             throw new LuaError( "Java Exception Thrown: " + t, 0 );
         }
+        finally
+        {
+            arguments.releaseImmediate();
+        }
 
         ILuaCallback callback = results.getCallback();
         Varargs ret = machine.toValues( results.getResult() );

src/main/java/dan200/computercraft/core/lua/TableImpl.java

@@ -0,0 +1,141 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+package dan200.computercraft.core.lua;
+
+import dan200.computercraft.api.lua.LuaException;
+import dan200.computercraft.api.lua.LuaValues;
+import org.squiddev.cobalt.*;
+
+import javax.annotation.Nonnull;
+import java.util.*;
+
+import static dan200.computercraft.api.lua.LuaValues.badTableItem;
+import static dan200.computercraft.api.lua.LuaValues.getNumericType;
+
+class TableImpl implements dan200.computercraft.api.lua.LuaTable<Object, Object>
+{
+    private final VarargArguments arguments;
+    private final LuaTable table;
+    private Map<Object, Object> backingMap;
+
+    TableImpl( VarargArguments arguments, LuaTable table )
+    {
+        this.arguments = arguments;
+        this.table = table;
+    }
+
+    @Override
+    public int size()
+    {
+        checkValid();
+        try
+        {
+            return table.keyCount();
+        }
+        catch( LuaError e )
+        {
+            throw new IllegalStateException( e );
+        }
+    }
+
+    @Override
+    public int length()
+    {
+        return table.length();
+    }
+
+    @Override
+    public long getLong( int index ) throws LuaException
+    {
+        LuaValue value = table.rawget( index );
+        if( !(value instanceof LuaNumber) ) throw LuaValues.badTableItem( index, "number", value.typeName() );
+        if( value instanceof LuaInteger ) return value.toInteger();
+
+        double number = value.toDouble();
+        if( !Double.isFinite( number ) ) throw badTableItem( index, "number", getNumericType( number ) );
+        return (long) number;
+    }
+
+    @Override
+    public boolean isEmpty()
+    {
+        checkValid();
+        try
+        {
+            return table.next( Constants.NIL ).first().isNil();
+        }
+        catch( LuaError e )
+        {
+            throw new IllegalStateException( e );
+        }
+    }
+
+    @Nonnull
+    private LuaValue getImpl( Object o )
+    {
+        checkValid();
+        if( o instanceof String ) return table.rawget( (String) o );
+        if( o instanceof Integer ) return table.rawget( (Integer) o );
+        return Constants.NIL;
+    }
+
+    @Override
+    public boolean containsKey( Object o )
+    {
+        return !getImpl( o ).isNil();
+    }
+
+    @Override
+    public Object get( Object o )
+    {
+        return CobaltLuaMachine.toObject( getImpl( o ), null );
+    }
+
+    @Nonnull
+    private Map<Object, Object> getBackingMap()
+    {
+        checkValid();
+        if( backingMap != null ) return backingMap;
+        return backingMap = Collections.unmodifiableMap(
+            Objects.requireNonNull( (Map<?, ?>) CobaltLuaMachine.toObject( table, null ) )
+        );
+    }
+
+    @Override
+    public boolean containsValue( Object o )
+    {
+        return getBackingMap().containsKey( o );
+    }
+
+    @Nonnull
+    @Override
+    public Set<Object> keySet()
+    {
+        return getBackingMap().keySet();
+    }
+
+    @Nonnull
+    @Override
+    public Collection<Object> values()
+    {
+        return getBackingMap().values();
+    }
+
+    @Nonnull
+    @Override
+    public Set<Entry<Object, Object>> entrySet()
+    {
+        return getBackingMap().entrySet();
+    }
+
+    private void checkValid()
+    {
+        if( arguments.released )
+        {
+            throw new IllegalStateException( "Cannot use LuaTable after IArguments has been released" );
+        }
+    }
+}

src/main/java/dan200/computercraft/core/lua/VarargArguments.java

@@ -19,6 +19,7 @@ class VarargArguments implements IArguments
 {
     static final IArguments EMPTY = new VarargArguments( Constants.NONE );
 
+    boolean released;
     private final Varargs varargs;
     private Object[] cache;
 
@@ -98,4 +99,39 @@ class VarargArguments implements IArguments
         LuaString str = ((LuaBaseString) value).strvalue();
         return Optional.of( ByteBuffer.wrap( str.bytes, str.offset, str.length ).asReadOnlyBuffer() );
     }
+
+    @Nonnull
+    @Override
+    public dan200.computercraft.api.lua.LuaTable<?, ?> getTableUnsafe( int index ) throws LuaException
+    {
+        if( released )
+        {
+            throw new IllegalStateException( "Cannot use getTableUnsafe after IArguments has been released" );
+        }
+
+        LuaValue value = varargs.arg( index + 1 );
+        if( !(value instanceof LuaTable) ) throw LuaValues.badArgument( index, "table", value.typeName() );
+        return new TableImpl( this, (LuaTable) value );
+    }
+
+    @Nonnull
+    @Override
+    public Optional<dan200.computercraft.api.lua.LuaTable<?, ?>> optTableUnsafe( int index ) throws LuaException
+    {
+        if( released )
+        {
+            throw new IllegalStateException( "Cannot use optTableUnsafe after IArguments has been released" );
+        }
+
+        LuaValue value = varargs.arg( index + 1 );
+        if( value.isNil() ) return Optional.empty();
+        if( !(value instanceof LuaTable) ) throw LuaValues.badArgument( index, "table", value.typeName() );
+        return Optional.of( new TableImpl( this, (LuaTable) value ) );
+    }
+
+    @Override
+    public void releaseImmediate()
+    {
+        released = true;
+    }
 }

src/main/java/dan200/computercraft/fabric/events/ClientUnloadWorldEvent.java

@@ -1,23 +0,0 @@
-/*
- * This file is part of ComputerCraft - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
- * Send enquiries to dratcliffe@gmail.com
- */
-package dan200.computercraft.fabric.events;
-
-import net.fabricmc.fabric.api.event.Event;
-import net.fabricmc.fabric.api.event.EventFactory;
-
-@FunctionalInterface
-public interface ClientUnloadWorldEvent
-{
-    Event<ClientUnloadWorldEvent> EVENT = EventFactory.createArrayBacked( ClientUnloadWorldEvent.class,
-        callbacks -> () -> {
-            for( ClientUnloadWorldEvent callback : callbacks )
-            {
-                callback.onClientUnloadWorld();
-            }
-        } );
-
-    void onClientUnloadWorld();
-}

src/main/java/dan200/computercraft/fabric/events/ComputerCraftCustomEvents.java

@@ -0,0 +1,42 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+package dan200.computercraft.fabric.events;
+
+import net.fabricmc.fabric.api.event.Event;
+import net.fabricmc.fabric.api.event.EventFactory;
+import net.minecraft.server.level.ServerPlayer;
+import net.minecraft.world.level.ChunkPos;
+
+public final class ComputerCraftCustomEvents
+{
+    public static final Event<ClientUnloadWorld> CLIENT_UNLOAD_WORLD_EVENT = EventFactory.createArrayBacked( ClientUnloadWorld.class,
+        callbacks -> () -> {
+            for( ClientUnloadWorld callback : callbacks )
+            {
+                callback.onClientUnloadWorld();
+            }
+        } );
+
+    public static final Event<ServerPlayerLoadedChunk> SERVER_PLAYER_LOADED_CHUNK_EVENT = EventFactory.createArrayBacked( ServerPlayerLoadedChunk.class,
+        callbacks -> ( serverPlayer, chunkPos ) -> {
+            for( ServerPlayerLoadedChunk callback : callbacks )
+            {
+                callback.onServerPlayerLoadedChunk( serverPlayer, chunkPos );
+            }
+        } );
+
+    @FunctionalInterface
+    public interface ClientUnloadWorld
+    {
+        void onClientUnloadWorld();
+    }
+
+    @FunctionalInterface
+    public interface ServerPlayerLoadedChunk
+    {
+        void onServerPlayerLoadedChunk( ServerPlayer player, ChunkPos chunkPos );
+    }
+}

src/main/java/dan200/computercraft/fabric/mixin/MixinChunkMap.java

@@ -0,0 +1,52 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+package dan200.computercraft.fabric.mixin;
+
+import dan200.computercraft.shared.peripheral.monitor.MonitorWatcher;
+import net.minecraft.network.protocol.game.ClientboundLevelChunkWithLightPacket;
+import net.minecraft.server.level.ChunkMap;
+import net.minecraft.server.level.ServerLevel;
+import net.minecraft.server.level.ServerPlayer;
+import net.minecraft.world.level.chunk.LevelChunk;
+import org.apache.commons.lang3.mutable.MutableObject;
+import org.spongepowered.asm.mixin.Final;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+@Mixin( ChunkMap.class )
+public class MixinChunkMap
+{
+    @Final
+    @Shadow
+    ServerLevel level;
+
+    /*
+    * This mixin mimics the logic of Forge's ChunkWatchEvent.Watch but I don't believe it behaves as expected. Instead
+    * of firing once when the player initially come in server view distance of a chunk, it fires every time
+    * the chunk is checked against the player's view distance. This continually happens every tick that the player
+    * moves (or even rotates in place).
+    */
+
+    //    @Inject( method = "updateChunkTracking", at = @At( value = "HEAD" ) )
+    //    public void updateChunkTracking( ServerPlayer serverPlayer, ChunkPos chunkPos, MutableObject<ClientboundLevelChunkWithLightPacket> mutableObject, boolean bl, boolean bl2, CallbackInfo ci )
+    //    {
+    //        if( serverPlayer.level == this.level && bl )
+    //        {
+    //            ComputerCraftCustomEvents.SERVER_PLAYER_LOADED_CHUNK_EVENT.invoker().onServerPlayerLoadedChunk( serverPlayer, chunkPos );
+    //        }
+    //    }
+
+    // This version behaves as expected in my testing.
+    @Inject( method = "playerLoadedChunk", at = @At( value = "HEAD" ) )
+    private void playerLoadedChunk( ServerPlayer serverPlayer, MutableObject<ClientboundLevelChunkWithLightPacket> mutableObject, LevelChunk levelChunk, CallbackInfo ci )
+    {
+        MonitorWatcher.onWatch( serverPlayer, levelChunk.getPos() );
+    }
+
+}

src/main/java/dan200/computercraft/fabric/mixin/MixinLevel.java

@@ -1,59 +0,0 @@
-/*
- * This file is part of ComputerCraft - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
- * Send enquiries to dratcliffe@gmail.com
- */
-package dan200.computercraft.fabric.mixin;
-
-import dan200.computercraft.shared.common.TileGeneric;
-import net.minecraft.world.level.Level;
-import net.minecraft.world.level.block.entity.BlockEntity;
-import org.spongepowered.asm.mixin.Mixin;
-import org.spongepowered.asm.mixin.Shadow;
-import org.spongepowered.asm.mixin.injection.At;
-import org.spongepowered.asm.mixin.injection.Inject;
-import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
-
-import javax.annotation.Nullable;
-import java.util.Collection;
-
-/**
- * Horrible bodge to ensure a {@link BlockEntity}'s world is always present when setting a TE during another TE's tick.
- *
- * Forge does this, this is just a bodge to get Fabric in line with that behaviour.
- */
-@Mixin( Level.class )
-public class MixinLevel
-{
-    @Shadow
-    protected boolean tickingBlockEntities;
-
-    @Inject( method = "setBlockEntity", at = @At( "HEAD" ) )
-    public void setBlockEntity( @Nullable BlockEntity entity, CallbackInfo info )
-    {
-        if( entity != null && !entity.isRemoved() && entity.getLevel().isInWorldBounds( entity.getBlockPos() ) && tickingBlockEntities )
-        {
-            setWorld( entity, this );
-        }
-    }
-
-    private static void setWorld( BlockEntity entity, Object world )
-    {
-        if( entity.getLevel() != world && entity instanceof TileGeneric )
-        {
-            entity.setLevel( (Level) world ); //TODO why?
-        }
-    }
-
-    //    @Inject( method = "addBlockEntities", at = @At( "HEAD" ) )
-    public void addBlockEntities( Collection<BlockEntity> entities, CallbackInfo info )
-    {
-        if( tickingBlockEntities )
-        {
-            for( BlockEntity entity : entities )
-            {
-                setWorld( entity, this );
-            }
-        }
-    }
-}

src/main/java/dan200/computercraft/fabric/mixin/MixinMinecraft.java

@@ -6,7 +6,7 @@
 package dan200.computercraft.fabric.mixin;
 
 import dan200.computercraft.client.FrameInfo;
-import dan200.computercraft.fabric.events.ClientUnloadWorldEvent;
+import dan200.computercraft.fabric.events.ComputerCraftCustomEvents;
 import net.minecraft.client.Minecraft;
 import net.minecraft.client.gui.screens.Screen;
 import net.minecraft.client.multiplayer.ClientLevel;
@@ -27,12 +27,12 @@ public abstract class MixinMinecraft
     @Inject( method = "clearLevel(Lnet/minecraft/client/gui/screens/Screen;)V", at = @At( "RETURN" ) )
     private void disconnectAfter( Screen screen, CallbackInfo info )
     {
-        ClientUnloadWorldEvent.EVENT.invoker().onClientUnloadWorld();
+        ComputerCraftCustomEvents.CLIENT_UNLOAD_WORLD_EVENT.invoker().onClientUnloadWorld();
     }
 
     @Inject( method = "setLevel", at = @At( "RETURN" ) )
     private void setLevel( ClientLevel world, CallbackInfo info )
     {
-        ClientUnloadWorldEvent.EVENT.invoker().onClientUnloadWorld();
+        ComputerCraftCustomEvents.CLIENT_UNLOAD_WORLD_EVENT.invoker().onClientUnloadWorld();
     }
 }

src/main/java/dan200/computercraft/fabric/mixin/MixinServerPlayerGameMode.java

@@ -5,7 +5,7 @@
  */
 package dan200.computercraft.fabric.mixin;
 
-import dan200.computercraft.shared.ComputerCraftRegistry;
+import dan200.computercraft.shared.Registry;
 import net.minecraft.advancements.CriteriaTriggers;
 import net.minecraft.core.BlockPos;
 import net.minecraft.server.level.ServerPlayer;
@@ -33,7 +33,7 @@ public class MixinServerPlayerGameMode
     {
         BlockPos pos = hitResult.getBlockPos();
         BlockState state = world.getBlockState( pos );
-        if( player.getMainHandItem().getItem() == ComputerCraftRegistry.ModItems.DISK && state.getBlock() == ComputerCraftRegistry.ModBlocks.DISK_DRIVE )
+        if( player.getMainHandItem().getItem() == Registry.ModItems.DISK && state.getBlock() == Registry.ModBlocks.DISK_DRIVE )
         {
             InteractionResult actionResult = state.use( world, player, hand, hitResult );
             if( actionResult.consumesAction() )

src/main/java/dan200/computercraft/shared/BundledRedstone.java

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.shared;
 
 import dan200.computercraft.ComputerCraft;
@@ -34,18 +33,9 @@ public final class BundledRedstone
         return world.isInWorldBounds( pos ) ? DefaultBundledRedstoneProvider.getDefaultBundledRedstoneOutput( world, pos, side ) : -1;
     }
 
-    public static int getOutput( Level world, BlockPos pos, Direction side )
-    {
-        int signal = getUnmaskedOutput( world, pos, side );
-        return signal >= 0 ? signal : 0;
-    }
-
     private static int getUnmaskedOutput( Level world, BlockPos pos, Direction side )
     {
-        if( !world.isInWorldBounds( pos ) )
-        {
-            return -1;
-        }
+        if( !world.isInWorldBounds( pos ) ) return -1;
 
         // Try the providers in order:
         int combinedSignal = -1;
@@ -67,4 +57,10 @@ public final class BundledRedstone
 
         return combinedSignal;
     }
+
+    public static int getOutput( Level world, BlockPos pos, Direction side )
+    {
+        int signal = getUnmaskedOutput( world, pos, side );
+        return signal >= 0 ? signal : 0;
+    }
 }

src/main/java/dan200/computercraft/shared/ComputerCraftRegistry.java

@@ -1,330 +0,0 @@
-/*
- * This file is part of ComputerCraft - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
- * Send enquiries to dratcliffe@gmail.com
- */
-
-package dan200.computercraft.shared;
-
-import dan200.computercraft.ComputerCraft;
-import dan200.computercraft.api.ComputerCraftAPI;
-import dan200.computercraft.shared.common.ContainerHeldItem;
-import dan200.computercraft.shared.computer.blocks.BlockComputer;
-import dan200.computercraft.shared.computer.blocks.TileCommandComputer;
-import dan200.computercraft.shared.computer.blocks.TileComputer;
-import dan200.computercraft.shared.computer.core.ComputerFamily;
-import dan200.computercraft.shared.computer.inventory.ComputerMenuWithoutInventory;
-import dan200.computercraft.shared.computer.inventory.ContainerComputerBase;
-import dan200.computercraft.shared.computer.inventory.ContainerViewComputer;
-import dan200.computercraft.shared.computer.items.ItemComputer;
-import dan200.computercraft.shared.media.items.ItemDisk;
-import dan200.computercraft.shared.media.items.ItemPrintout;
-import dan200.computercraft.shared.media.items.ItemTreasureDisk;
-import dan200.computercraft.shared.network.container.ComputerContainerData;
-import dan200.computercraft.shared.network.container.ContainerData;
-import dan200.computercraft.shared.network.container.HeldItemContainerData;
-import dan200.computercraft.shared.network.container.ViewComputerContainerData;
-import dan200.computercraft.shared.peripheral.diskdrive.BlockDiskDrive;
-import dan200.computercraft.shared.peripheral.diskdrive.ContainerDiskDrive;
-import dan200.computercraft.shared.peripheral.diskdrive.TileDiskDrive;
-import dan200.computercraft.shared.peripheral.modem.wired.*;
-import dan200.computercraft.shared.peripheral.modem.wireless.BlockWirelessModem;
-import dan200.computercraft.shared.peripheral.modem.wireless.TileWirelessModem;
-import dan200.computercraft.shared.peripheral.monitor.BlockMonitor;
-import dan200.computercraft.shared.peripheral.monitor.TileMonitor;
-import dan200.computercraft.shared.peripheral.printer.BlockPrinter;
-import dan200.computercraft.shared.peripheral.printer.ContainerPrinter;
-import dan200.computercraft.shared.peripheral.printer.TilePrinter;
-import dan200.computercraft.shared.peripheral.speaker.BlockSpeaker;
-import dan200.computercraft.shared.peripheral.speaker.TileSpeaker;
-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.turtle.blocks.BlockTurtle;
-import dan200.computercraft.shared.turtle.blocks.TileTurtle;
-import dan200.computercraft.shared.turtle.core.TurtlePlayer;
-import dan200.computercraft.shared.turtle.inventory.ContainerTurtle;
-import dan200.computercraft.shared.turtle.items.ItemTurtle;
-import dan200.computercraft.shared.turtle.upgrades.*;
-import net.fabricmc.fabric.api.object.builder.v1.block.FabricBlockSettings;
-import net.fabricmc.fabric.api.object.builder.v1.block.entity.FabricBlockEntityTypeBuilder;
-import net.fabricmc.fabric.api.screenhandler.v1.ScreenHandlerRegistry;
-import net.fabricmc.fabric.api.tool.attribute.v1.FabricToolTags;
-import net.minecraft.core.BlockPos;
-import net.minecraft.core.Registry;
-import net.minecraft.resources.ResourceLocation;
-import net.minecraft.world.entity.EntityType;
-import net.minecraft.world.entity.MobCategory;
-import net.minecraft.world.inventory.AbstractContainerMenu;
-import net.minecraft.world.inventory.MenuType;
-import net.minecraft.world.item.BlockItem;
-import net.minecraft.world.item.CreativeModeTab;
-import net.minecraft.world.item.Item;
-import net.minecraft.world.item.Items;
-import net.minecraft.world.level.block.Block;
-import net.minecraft.world.level.block.Blocks;
-import net.minecraft.world.level.block.SoundType;
-import net.minecraft.world.level.block.entity.BlockEntity;
-import net.minecraft.world.level.block.entity.BlockEntityType;
-import net.minecraft.world.level.block.state.BlockBehaviour;
-import net.minecraft.world.level.block.state.BlockState;
-import net.minecraft.world.level.material.Material;
-
-import java.util.function.BiFunction;
-
-import static net.minecraft.core.Registry.BLOCK_ENTITY_TYPE;
-
-public final class ComputerCraftRegistry
-{
-    public static final String MOD_ID = ComputerCraft.MOD_ID;
-
-    public static void init()
-    {
-        Object[] o = {
-            ModTiles.CABLE,
-            ModBlocks.CABLE,
-            ModItems.CABLE,
-            ModEntities.TURTLE_PLAYER,
-            ModContainers.COMPUTER,
-        };
-
-        TurtleUpgrades.registerTurtleUpgrades();
-        PocketUpgrades.registerPocketUpgrades();
-    }
-
-    public static final class ModBlocks
-    {
-        public static final BlockComputer COMPUTER_NORMAL = register( "computer_normal",
-            new BlockComputer( properties(), ComputerFamily.NORMAL, ComputerCraftRegistry.ModTiles.COMPUTER_NORMAL ) );
-        public static final BlockComputer COMPUTER_ADVANCED = register( "computer_advanced",
-            new BlockComputer( properties(),
-                ComputerFamily.ADVANCED,
-                ComputerCraftRegistry.ModTiles.COMPUTER_ADVANCED ) );
-        public static final BlockComputer COMPUTER_COMMAND = register( "computer_command",
-            new BlockComputer( FabricBlockSettings.copyOf( Blocks.STONE )
-                .strength( -1, 6000000.0F ),
-                ComputerFamily.COMMAND,
-                ComputerCraftRegistry.ModTiles.COMPUTER_COMMAND ) );
-        public static final BlockTurtle TURTLE_NORMAL = register( "turtle_normal",
-            new BlockTurtle( turtleProperties(), ComputerFamily.NORMAL, ComputerCraftRegistry.ModTiles.TURTLE_NORMAL ) );
-        public static final BlockTurtle TURTLE_ADVANCED = register( "turtle_advanced",
-            new BlockTurtle( turtleProperties(), ComputerFamily.ADVANCED, ComputerCraftRegistry.ModTiles.TURTLE_ADVANCED ) );
-        public static final BlockSpeaker SPEAKER = register( "speaker", new BlockSpeaker( properties() ) );
-        public static final BlockDiskDrive DISK_DRIVE = register( "disk_drive", new BlockDiskDrive( properties() ) );
-        public static final BlockPrinter PRINTER = register( "printer", new BlockPrinter( properties() ) );
-        public static final BlockMonitor MONITOR_NORMAL = register( "monitor_normal", new BlockMonitor( properties(), ModTiles.MONITOR_NORMAL, false ) );
-        public static final BlockMonitor MONITOR_ADVANCED = register( "monitor_advanced", new BlockMonitor( properties(), ModTiles.MONITOR_ADVANCED, true ) );
-        public static final BlockWirelessModem WIRELESS_MODEM_NORMAL = register( "wireless_modem_normal",
-            new BlockWirelessModem( properties(), ComputerCraftRegistry.ModTiles.WIRELESS_MODEM_NORMAL, ComputerFamily.NORMAL ) );
-        public static final BlockWirelessModem WIRELESS_MODEM_ADVANCED = register( "wireless_modem_advanced",
-            new BlockWirelessModem( properties(), ComputerCraftRegistry.ModTiles.WIRELESS_MODEM_ADVANCED, ComputerFamily.ADVANCED ) );
-        public static final BlockWiredModemFull WIRED_MODEM_FULL = register( "wired_modem_full",
-            new BlockWiredModemFull( modemProperties(), ComputerCraftRegistry.ModTiles.WIRED_MODEM_FULL ) );
-        public static final BlockCable CABLE = register( "cable", new BlockCable( modemProperties() ) );
-
-        private static BlockBehaviour.Properties properties()
-        {
-            //return FabricBlockSettings.copyOf(Blocks.GLASS)
-            //                        .strength(2);
-            return BlockBehaviour.Properties.of( Material.GLASS )
-                .strength( 2F )
-                .sound( SoundType.STONE )
-                .noOcclusion();
-        }
-
-        private static BlockBehaviour.Properties turtleProperties()
-        {
-            return FabricBlockSettings.copyOf( Blocks.STONE )
-                .strength( 2.5f );
-        }
-
-        private static BlockBehaviour.Properties modemProperties()
-        {
-            return FabricBlockSettings.copyOf( Blocks.STONE )
-                .breakByHand( true )
-                .breakByTool( FabricToolTags.PICKAXES )
-                .strength( 1.5f );
-        }
-
-        public static <T extends Block> T register( String id, T value )
-        {
-            return Registry.register( Registry.BLOCK, new ResourceLocation( MOD_ID, id ), value );
-        }
-    }
-
-    public static class ModTiles
-    {
-
-        public static final BlockEntityType<TileMonitor> MONITOR_NORMAL = ofBlock( ModBlocks.MONITOR_NORMAL,
-            "monitor_normal",
-            ( blockPos, blockState ) -> new TileMonitor( ModTiles.MONITOR_NORMAL, false, blockPos, blockState ) );
-        public static final BlockEntityType<TileMonitor> MONITOR_ADVANCED = ofBlock( ModBlocks.MONITOR_ADVANCED,
-            "monitor_advanced",
-            ( blockPos, blockState ) -> new TileMonitor( ModTiles.MONITOR_ADVANCED, true, blockPos, blockState ) );
-        public static final BlockEntityType<TileComputer> COMPUTER_NORMAL = ofBlock( ModBlocks.COMPUTER_NORMAL,
-            "computer_normal",
-            ( blockPos, blockState ) -> new TileComputer( ComputerFamily.NORMAL, ModTiles.COMPUTER_NORMAL, blockPos, blockState ) );
-        public static final BlockEntityType<TileComputer> COMPUTER_ADVANCED = ofBlock( ModBlocks.COMPUTER_ADVANCED,
-            "computer_advanced",
-            ( blockPos, blockState ) -> new TileComputer( ComputerFamily.ADVANCED, ModTiles.COMPUTER_ADVANCED, blockPos, blockState ) );
-        public static final BlockEntityType<TileCommandComputer> COMPUTER_COMMAND = ofBlock( ModBlocks.COMPUTER_COMMAND,
-            "computer_command",
-            ( blockPos, blockState ) -> new TileCommandComputer( ComputerFamily.COMMAND, ModTiles.COMPUTER_COMMAND, blockPos, blockState ) );
-        public static final BlockEntityType<TileTurtle> TURTLE_NORMAL = ofBlock( ModBlocks.TURTLE_NORMAL,
-            "turtle_normal",
-            ( blockPos, blockState ) -> new TileTurtle( ModTiles.TURTLE_NORMAL, blockPos, blockState, ComputerFamily.NORMAL ) );
-        public static final BlockEntityType<TileTurtle> TURTLE_ADVANCED = ofBlock( ModBlocks.TURTLE_ADVANCED,
-            "turtle_advanced",
-            ( blockPos, blockState ) -> new TileTurtle( ModTiles.TURTLE_ADVANCED, blockPos, blockState, ComputerFamily.ADVANCED ) );
-        public static final BlockEntityType<TileSpeaker> SPEAKER = ofBlock( ModBlocks.SPEAKER, "speaker",
-            ( blockPos, blockState ) -> new TileSpeaker( ModTiles.SPEAKER, blockPos, blockState ) );
-        public static final BlockEntityType<TileDiskDrive> DISK_DRIVE = ofBlock( ModBlocks.DISK_DRIVE, "disk_drive",
-            ( blockPos, blockState ) -> new TileDiskDrive( ModTiles.DISK_DRIVE, blockPos, blockState ) );
-        public static final BlockEntityType<TilePrinter> PRINTER = ofBlock( ModBlocks.PRINTER, "printer",
-            ( blockPos, blockState ) -> new TilePrinter( ModTiles.PRINTER, blockPos, blockState ) );
-        public static final BlockEntityType<TileWiredModemFull> WIRED_MODEM_FULL = ofBlock( ModBlocks.WIRED_MODEM_FULL,
-            "wired_modem_full",
-            ( blockPos, blockState ) -> new TileWiredModemFull( ModTiles.WIRED_MODEM_FULL, blockPos, blockState ) );
-        public static final BlockEntityType<TileCable> CABLE = ofBlock( ModBlocks.CABLE, "cable",
-            ( blockPos, blockState ) -> new TileCable( ModTiles.CABLE, blockPos, blockState ) );
-        public static final BlockEntityType<TileWirelessModem> WIRELESS_MODEM_NORMAL = ofBlock( ModBlocks.WIRELESS_MODEM_NORMAL,
-            "wireless_modem_normal",
-            ( blockPos, blockState ) -> new TileWirelessModem( ModTiles.WIRELESS_MODEM_NORMAL, false, blockPos, blockState ) );
-        public static final BlockEntityType<TileWirelessModem> WIRELESS_MODEM_ADVANCED = ofBlock( ModBlocks.WIRELESS_MODEM_ADVANCED,
-            "wireless_modem_advanced",
-            ( blockPos, blockState ) -> new TileWirelessModem( ModTiles.WIRELESS_MODEM_ADVANCED, true, blockPos, blockState ) );
-
-        private static <T extends BlockEntity> BlockEntityType<T> ofBlock( Block block, String id, BiFunction<BlockPos, BlockState, T> factory )
-        {
-            BlockEntityType<T> blockEntityType = FabricBlockEntityTypeBuilder.create( factory::apply, block ).build();
-            return Registry.register( BLOCK_ENTITY_TYPE,
-                new ResourceLocation( MOD_ID, id ),
-                blockEntityType
-            );
-        }
-    }
-
-    public static final class ModItems
-    {
-        private static final CreativeModeTab mainItemGroup = ComputerCraft.MAIN_GROUP;
-        public static final ItemComputer COMPUTER_NORMAL = ofBlock( ModBlocks.COMPUTER_NORMAL, ItemComputer::new );
-        public static final ItemComputer COMPUTER_ADVANCED = ofBlock( ModBlocks.COMPUTER_ADVANCED, ItemComputer::new );
-        public static final ItemComputer COMPUTER_COMMAND = ofBlock( ModBlocks.COMPUTER_COMMAND, ItemComputer::new );
-        public static final ItemPocketComputer POCKET_COMPUTER_NORMAL = register( "pocket_computer_normal",
-            new ItemPocketComputer( properties().stacksTo( 1 ), ComputerFamily.NORMAL ) );
-        public static final ItemPocketComputer POCKET_COMPUTER_ADVANCED = register( "pocket_computer_advanced",
-            new ItemPocketComputer( properties().stacksTo( 1 ),
-                ComputerFamily.ADVANCED ) );
-        public static final ItemTurtle TURTLE_NORMAL = ofBlock( ModBlocks.TURTLE_NORMAL, ItemTurtle::new );
-        public static final ItemTurtle TURTLE_ADVANCED = ofBlock( ModBlocks.TURTLE_ADVANCED, ItemTurtle::new );
-        public static final ItemDisk DISK = register( "disk", new ItemDisk( properties().stacksTo( 1 ) ) );
-        public static final ItemTreasureDisk TREASURE_DISK = register( "treasure_disk", new ItemTreasureDisk( properties().stacksTo( 1 ) ) );
-        public static final ItemPrintout PRINTED_PAGE = register( "printed_page", new ItemPrintout( properties().stacksTo( 1 ), ItemPrintout.Type.PAGE ) );
-        public static final ItemPrintout PRINTED_PAGES = register( "printed_pages", new ItemPrintout( properties().stacksTo( 1 ), ItemPrintout.Type.PAGES ) );
-        public static final ItemPrintout PRINTED_BOOK = register( "printed_book", new ItemPrintout( properties().stacksTo( 1 ), ItemPrintout.Type.BOOK ) );
-        public static final BlockItem SPEAKER = ofBlock( ModBlocks.SPEAKER, BlockItem::new );
-        public static final BlockItem DISK_DRIVE = ofBlock( ModBlocks.DISK_DRIVE, BlockItem::new );
-        public static final BlockItem PRINTER = ofBlock( ModBlocks.PRINTER, BlockItem::new );
-        public static final BlockItem MONITOR_NORMAL = ofBlock( ModBlocks.MONITOR_NORMAL, BlockItem::new );
-        public static final BlockItem MONITOR_ADVANCED = ofBlock( ModBlocks.MONITOR_ADVANCED, BlockItem::new );
-        public static final BlockItem WIRELESS_MODEM_NORMAL = ofBlock( ModBlocks.WIRELESS_MODEM_NORMAL, BlockItem::new );
-        public static final BlockItem WIRELESS_MODEM_ADVANCED = ofBlock( ModBlocks.WIRELESS_MODEM_ADVANCED, BlockItem::new );
-        public static final BlockItem WIRED_MODEM_FULL = ofBlock( ModBlocks.WIRED_MODEM_FULL, BlockItem::new );
-        public static final ItemBlockCable.Cable CABLE = register( "cable", new ItemBlockCable.Cable( ModBlocks.CABLE, properties() ) );
-        public static final ItemBlockCable.WiredModem WIRED_MODEM = register( "wired_modem", new ItemBlockCable.WiredModem( ModBlocks.CABLE, properties() ) );
-
-        private static <B extends Block, I extends Item> I ofBlock( B parent, BiFunction<B, Item.Properties, I> supplier )
-        {
-            return Registry.register( Registry.ITEM, Registry.BLOCK.getKey( parent ), supplier.apply( parent, properties() ) );
-        }
-
-        private static Item.Properties properties()
-        {
-            return new Item.Properties().tab( mainItemGroup );
-        }
-
-        private static <T extends Item> T register( String id, T item )
-        {
-            return Registry.register( Registry.ITEM, new ResourceLocation( MOD_ID, id ), item );
-        }
-    }
-
-    public static class ModEntities
-    {
-        public static final EntityType<TurtlePlayer> TURTLE_PLAYER = Registry.register( Registry.ENTITY_TYPE,
-            new ResourceLocation( MOD_ID, "turtle_player" ),
-            EntityType.Builder.<TurtlePlayer>createNothing( MobCategory.MISC ).noSave()
-                .noSummon()
-                .sized(
-                    0,
-                    0 )
-                .build(
-                    ComputerCraft.MOD_ID + ":turtle_player" ) );
-    }
-
-    public static class ModContainers
-    {
-        public static final MenuType<ContainerComputerBase> COMPUTER = ContainerData.toType( new ResourceLocation( MOD_ID, "computer" ), ModContainers.COMPUTER, ComputerContainerData::new, ComputerMenuWithoutInventory::new );
-        public static final MenuType<ContainerComputerBase> POCKET_COMPUTER = ContainerData.toType( new ResourceLocation( MOD_ID, "pocket_computer" ), ModContainers.POCKET_COMPUTER, ComputerContainerData::new, ComputerMenuWithoutInventory::new );
-        public static final MenuType<ContainerComputerBase> POCKET_COMPUTER_NO_TERM = ContainerData.toType( new ResourceLocation( MOD_ID, "pocket_computer_no_term" ), ModContainers.POCKET_COMPUTER_NO_TERM, ComputerContainerData::new, ComputerMenuWithoutInventory::new );
-        public static final MenuType<ContainerTurtle> TURTLE = ContainerData.toType( new ResourceLocation( MOD_ID, "turtle" ), ComputerContainerData::new, ContainerTurtle::new );
-        public static final MenuType<ContainerDiskDrive> DISK_DRIVE = registerSimple( "disk_drive", ContainerDiskDrive::new );
-        public static final MenuType<ContainerPrinter> PRINTER = registerSimple( "printer", ContainerPrinter::new );
-        public static final MenuType<ContainerHeldItem> PRINTOUT = ContainerData.toType( new ResourceLocation( MOD_ID, "printout" ), HeldItemContainerData::new, ContainerHeldItem::createPrintout );
-        public static final MenuType<ContainerViewComputer> VIEW_COMPUTER = ContainerData.toType( new ResourceLocation( MOD_ID, "view_computer" ), ViewComputerContainerData::new, ContainerViewComputer::new );
-
-        private static <T extends AbstractContainerMenu> MenuType<T> registerSimple( String id,
-                                                                                     ScreenHandlerRegistry.SimpleClientHandlerFactory<T> function )
-        {
-            return ScreenHandlerRegistry.registerSimple( new ResourceLocation( MOD_ID, id ), function );
-        }
-    }
-
-    public static final class TurtleUpgrades
-    {
-        public static TurtleModem wirelessModemNormal = new TurtleModem( false, new ResourceLocation( ComputerCraft.MOD_ID, "wireless_modem_normal" ) );
-        public static TurtleModem wirelessModemAdvanced = new TurtleModem( true, new ResourceLocation( ComputerCraft.MOD_ID, "wireless_modem_advanced" ) );
-        public static TurtleSpeaker speaker = new TurtleSpeaker( new ResourceLocation( ComputerCraft.MOD_ID, "speaker" ) );
-
-        public static TurtleCraftingTable craftingTable = new TurtleCraftingTable( new ResourceLocation( "minecraft", "crafting_table" ) );
-        public static TurtleSword diamondSword = new TurtleSword( new ResourceLocation( "minecraft", "diamond_sword" ), Items.DIAMOND_SWORD );
-        public static TurtleShovel diamondShovel = new TurtleShovel( new ResourceLocation( "minecraft", "diamond_shovel" ), Items.DIAMOND_SHOVEL );
-        public static TurtleTool diamondPickaxe = new TurtleTool( new ResourceLocation( "minecraft", "diamond_pickaxe" ), Items.DIAMOND_PICKAXE );
-        public static TurtleAxe diamondAxe = new TurtleAxe( new ResourceLocation( "minecraft", "diamond_axe" ), Items.DIAMOND_AXE );
-        public static TurtleHoe diamondHoe = new TurtleHoe( new ResourceLocation( "minecraft", "diamond_hoe" ), Items.DIAMOND_HOE );
-
-        public static TurtleTool netheritePickaxe = new TurtleTool( new ResourceLocation( "minecraft", "netherite_pickaxe" ), Items.NETHERITE_PICKAXE );
-
-        public static void registerTurtleUpgrades()
-        {
-            ComputerCraftAPI.registerTurtleUpgrade( wirelessModemNormal );
-            ComputerCraftAPI.registerTurtleUpgrade( wirelessModemAdvanced );
-            ComputerCraftAPI.registerTurtleUpgrade( speaker );
-
-            ComputerCraftAPI.registerTurtleUpgrade( craftingTable );
-            ComputerCraftAPI.registerTurtleUpgrade( diamondSword );
-            ComputerCraftAPI.registerTurtleUpgrade( diamondShovel );
-            ComputerCraftAPI.registerTurtleUpgrade( diamondPickaxe );
-            ComputerCraftAPI.registerTurtleUpgrade( diamondAxe );
-            ComputerCraftAPI.registerTurtleUpgrade( diamondHoe );
-
-            ComputerCraftAPI.registerTurtleUpgrade( netheritePickaxe );
-        }
-    }
-
-    public static final class PocketUpgrades
-    {
-        public static PocketModem wirelessModemNormal = new PocketModem( false );
-        public static PocketModem wirelessModemAdvanced = new PocketModem( true );
-        public static PocketSpeaker speaker = new PocketSpeaker();
-
-        public static void registerPocketUpgrades()
-        {
-            ComputerCraftAPI.registerPocketUpgrade( wirelessModemNormal );
-            ComputerCraftAPI.registerPocketUpgrade( wirelessModemAdvanced );
-            ComputerCraftAPI.registerPocketUpgrade( speaker );
-        }
-    }
-
-
-}

src/main/java/dan200/computercraft/shared/MediaProviders.java

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.shared;
 
 import dan200.computercraft.ComputerCraft;
@@ -30,10 +29,7 @@ public final class MediaProviders
 
     public static IMedia get( @Nonnull ItemStack stack )
     {
-        if( stack.isEmpty() )
-        {
-            return null;
-        }
+        if( stack.isEmpty() ) return null;
 
         // Try the handlers in order:
         for( IMediaProvider mediaProvider : providers )
@@ -41,10 +37,7 @@ public final class MediaProviders
             try
             {
                 IMedia media = mediaProvider.getMedia( stack );
-                if( media != null )
-                {
-                    return media;
-                }
+                if( media != null ) return media;
             }
             catch( Exception e )
             {

src/main/java/dan200/computercraft/shared/Peripherals.java

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.shared;
 
 import dan200.computercraft.ComputerCraft;
@@ -47,10 +46,7 @@ public final class Peripherals
             try
             {
                 IPeripheral peripheral = peripheralProvider.getPeripheral( world, pos, side );
-                if( peripheral != null )
-                {
-                    return peripheral;
-                }
+                if( peripheral != null ) return peripheral;
             }
             catch( Exception e )
             {

src/main/java/dan200/computercraft/shared/PocketUpgrades.java

@@ -15,6 +15,7 @@ import net.minecraft.world.item.ItemStack;
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 import java.util.*;
+import java.util.stream.Stream;
 
 public final class PocketUpgrades
 {
@@ -72,17 +73,18 @@ public final class PocketUpgrades
         return upgradeOwners.get( upgrade );
     }
 
-    public static Iterable<IPocketUpgrade> getVanillaUpgrades()
-    {
-        List<IPocketUpgrade> vanilla = new ArrayList<>();
-        vanilla.add( ComputerCraftRegistry.PocketUpgrades.wirelessModemNormal );
-        vanilla.add( ComputerCraftRegistry.PocketUpgrades.wirelessModemAdvanced );
-        vanilla.add( ComputerCraftRegistry.PocketUpgrades.speaker );
-        return vanilla;
-    }
-
     public static Iterable<IPocketUpgrade> getUpgrades()
     {
         return Collections.unmodifiableCollection( upgrades.values() );
     }
+
+    public static Stream<IPocketUpgrade> getVanillaUpgrades()
+    {
+        List<IPocketUpgrade> vanilla = Arrays.asList(
+            Registry.PocketUpgrades.wirelessModemNormal,
+            Registry.PocketUpgrades.wirelessModemAdvanced,
+            Registry.PocketUpgrades.speaker
+        );
+        return vanilla.stream();
+    }
 }

src/main/java/dan200/computercraft/shared/Registry.java

@@ -0,0 +1,404 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+package dan200.computercraft.shared;
+
+import dan200.computercraft.ComputerCraft;
+import dan200.computercraft.api.ComputerCraftAPI;
+import dan200.computercraft.api.ComputerCraftTags;
+import dan200.computercraft.shared.common.ContainerHeldItem;
+import dan200.computercraft.shared.computer.blocks.BlockComputer;
+import dan200.computercraft.shared.computer.blocks.TileCommandComputer;
+import dan200.computercraft.shared.computer.blocks.TileComputer;
+import dan200.computercraft.shared.computer.core.ComputerFamily;
+import dan200.computercraft.shared.computer.inventory.ComputerMenuWithoutInventory;
+import dan200.computercraft.shared.computer.inventory.ContainerComputerBase;
+import dan200.computercraft.shared.computer.inventory.ContainerViewComputer;
+import dan200.computercraft.shared.computer.items.ItemComputer;
+import dan200.computercraft.shared.media.items.ItemDisk;
+import dan200.computercraft.shared.media.items.ItemPrintout;
+import dan200.computercraft.shared.media.items.ItemTreasureDisk;
+import dan200.computercraft.shared.network.container.ComputerContainerData;
+import dan200.computercraft.shared.network.container.ContainerData;
+import dan200.computercraft.shared.network.container.HeldItemContainerData;
+import dan200.computercraft.shared.network.container.ViewComputerContainerData;
+import dan200.computercraft.shared.peripheral.diskdrive.BlockDiskDrive;
+import dan200.computercraft.shared.peripheral.diskdrive.ContainerDiskDrive;
+import dan200.computercraft.shared.peripheral.diskdrive.TileDiskDrive;
+import dan200.computercraft.shared.peripheral.modem.wired.*;
+import dan200.computercraft.shared.peripheral.modem.wireless.BlockWirelessModem;
+import dan200.computercraft.shared.peripheral.modem.wireless.TileWirelessModem;
+import dan200.computercraft.shared.peripheral.monitor.BlockMonitor;
+import dan200.computercraft.shared.peripheral.monitor.TileMonitor;
+import dan200.computercraft.shared.peripheral.printer.BlockPrinter;
+import dan200.computercraft.shared.peripheral.printer.ContainerPrinter;
+import dan200.computercraft.shared.peripheral.printer.TilePrinter;
+import dan200.computercraft.shared.peripheral.speaker.BlockSpeaker;
+import dan200.computercraft.shared.peripheral.speaker.TileSpeaker;
+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.turtle.blocks.BlockTurtle;
+import dan200.computercraft.shared.turtle.blocks.TileTurtle;
+import dan200.computercraft.shared.turtle.core.TurtlePlayer;
+import dan200.computercraft.shared.turtle.inventory.ContainerTurtle;
+import dan200.computercraft.shared.turtle.items.ItemTurtle;
+import dan200.computercraft.shared.turtle.upgrades.*;
+import net.fabricmc.fabric.api.object.builder.v1.block.FabricBlockSettings;
+import net.fabricmc.fabric.api.object.builder.v1.block.entity.FabricBlockEntityTypeBuilder;
+import net.fabricmc.fabric.api.screenhandler.v1.ScreenHandlerRegistry;
+import net.fabricmc.fabric.api.tool.attribute.v1.FabricToolTags;
+import net.minecraft.core.BlockPos;
+import net.minecraft.core.cauldron.CauldronInteraction;
+import net.minecraft.resources.ResourceLocation;
+import net.minecraft.world.entity.EntityType;
+import net.minecraft.world.entity.MobCategory;
+import net.minecraft.world.inventory.AbstractContainerMenu;
+import net.minecraft.world.inventory.MenuType;
+import net.minecraft.world.item.*;
+import net.minecraft.world.level.block.Block;
+import net.minecraft.world.level.block.Blocks;
+import net.minecraft.world.level.block.SoundType;
+import net.minecraft.world.level.block.entity.BlockEntity;
+import net.minecraft.world.level.block.entity.BlockEntityType;
+import net.minecraft.world.level.block.state.BlockBehaviour;
+import net.minecraft.world.level.block.state.BlockState;
+import net.minecraft.world.level.material.Material;
+
+import java.util.function.BiFunction;
+
+import static net.minecraft.core.Registry.BLOCK_ENTITY_TYPE;
+
+public final class Registry
+{
+    public static final String MOD_ID = ComputerCraft.MOD_ID;
+
+    public static void init()
+    {
+        // Touch each static class to force static initializers to run
+        // Maybe there's a better way to do this :/
+        Object[] o = {
+            ModBlockEntities.CABLE,
+            ModBlocks.CABLE,
+            ModItems.CABLE,
+            ModEntities.TURTLE_PLAYER,
+            ModContainers.COMPUTER,
+        };
+
+        TurtleUpgrades.registerTurtleUpgrades();
+        PocketUpgrades.registerPocketUpgrades();
+
+        CauldronInteraction.WATER.put( ModItems.TURTLE_NORMAL, ItemTurtle.CAULDRON_INTERACTION );
+        CauldronInteraction.WATER.put( ModItems.TURTLE_ADVANCED, ItemTurtle.CAULDRON_INTERACTION );
+    }
+
+    public static final class ModBlocks
+    {
+        public static <T extends Block> T register( String id, T value )
+        {
+            return net.minecraft.core.Registry.register( net.minecraft.core.Registry.BLOCK, new ResourceLocation( MOD_ID, id ), value );
+        }
+
+        public static final BlockMonitor MONITOR_NORMAL =
+            register( "monitor_normal", new BlockMonitor( properties(), () -> ModBlockEntities.MONITOR_NORMAL ) );
+
+        public static final BlockMonitor MONITOR_ADVANCED =
+            register( "monitor_advanced", new BlockMonitor( properties(), () -> ModBlockEntities.MONITOR_ADVANCED ) );
+
+        public static final BlockComputer COMPUTER_NORMAL =
+            register( "computer_normal", new BlockComputer( properties(), ComputerFamily.NORMAL, () -> ModBlockEntities.COMPUTER_NORMAL ) );
+
+        public static final BlockComputer COMPUTER_ADVANCED =
+            register( "computer_advanced", new BlockComputer( properties(), ComputerFamily.ADVANCED, () -> ModBlockEntities.COMPUTER_ADVANCED ) );
+
+        public static final BlockComputer COMPUTER_COMMAND =
+            register( "computer_command", new BlockComputer( FabricBlockSettings.copyOf( Blocks.STONE ).strength( -1, 6000000.0F ), ComputerFamily.COMMAND, () -> ModBlockEntities.COMPUTER_COMMAND ) );
+
+        public static final BlockTurtle TURTLE_NORMAL =
+            register( "turtle_normal", new BlockTurtle( turtleProperties(), ComputerFamily.NORMAL, () -> ModBlockEntities.TURTLE_NORMAL ) );
+
+        public static final BlockTurtle TURTLE_ADVANCED =
+            register( "turtle_advanced", new BlockTurtle( turtleProperties(), ComputerFamily.ADVANCED, () -> ModBlockEntities.TURTLE_ADVANCED ) );
+
+        public static final BlockSpeaker SPEAKER =
+            register( "speaker", new BlockSpeaker( properties() ) );
+
+        public static final BlockDiskDrive DISK_DRIVE =
+            register( "disk_drive", new BlockDiskDrive( properties() ) );
+
+        public static final BlockPrinter PRINTER =
+            register( "printer", new BlockPrinter( properties() ) );
+
+        public static final BlockWirelessModem WIRELESS_MODEM_NORMAL =
+            register( "wireless_modem_normal", new BlockWirelessModem( properties(), () -> ModBlockEntities.WIRELESS_MODEM_NORMAL ) );
+
+        public static final BlockWirelessModem WIRELESS_MODEM_ADVANCED =
+            register( "wireless_modem_advanced", new BlockWirelessModem( properties(), () -> ModBlockEntities.WIRELESS_MODEM_ADVANCED ) );
+
+        public static final BlockWiredModemFull WIRED_MODEM_FULL =
+            register( "wired_modem_full", new BlockWiredModemFull( modemProperties() ) );
+
+        public static final BlockCable CABLE =
+            register( "cable", new BlockCable( modemProperties() ) );
+
+        private static BlockBehaviour.Properties properties()
+        {
+            return BlockBehaviour.Properties.of( Material.GLASS ).strength( 2F ).sound( SoundType.STONE ).noOcclusion();
+        }
+
+        private static BlockBehaviour.Properties turtleProperties()
+        {
+            return FabricBlockSettings.copyOf( Blocks.STONE ).strength( 2.5f );
+        }
+
+        private static BlockBehaviour.Properties modemProperties()
+        {
+            return FabricBlockSettings.copyOf( Blocks.STONE ).breakByHand( true ).breakByTool( FabricToolTags.PICKAXES ).strength( 1.5f );
+        }
+    }
+
+    public static class ModBlockEntities
+    {
+        private static <T extends BlockEntity> BlockEntityType<T> ofBlock( Block block, String id, BiFunction<BlockPos, BlockState, T> factory )
+        {
+            BlockEntityType<T> blockEntityType = FabricBlockEntityTypeBuilder.create( factory::apply, block ).build();
+            return net.minecraft.core.Registry.register( BLOCK_ENTITY_TYPE, new ResourceLocation( MOD_ID, id ), blockEntityType );
+        }
+
+        public static final BlockEntityType<TileMonitor> MONITOR_NORMAL =
+            ofBlock( ModBlocks.MONITOR_NORMAL, "monitor_normal", ( blockPos, blockState ) -> new TileMonitor( ModBlockEntities.MONITOR_NORMAL, blockPos, blockState, false ) );
+
+        public static final BlockEntityType<TileMonitor> MONITOR_ADVANCED =
+            ofBlock( ModBlocks.MONITOR_ADVANCED, "monitor_advanced", ( blockPos, blockState ) -> new TileMonitor( ModBlockEntities.MONITOR_ADVANCED, blockPos, blockState, true ) );
+
+        public static final BlockEntityType<TileComputer> COMPUTER_NORMAL =
+            ofBlock( ModBlocks.COMPUTER_NORMAL, "computer_normal", ( blockPos, blockState ) -> new TileComputer( ModBlockEntities.COMPUTER_NORMAL, blockPos, blockState, ComputerFamily.NORMAL ) );
+
+        public static final BlockEntityType<TileComputer> COMPUTER_ADVANCED =
+            ofBlock( ModBlocks.COMPUTER_ADVANCED, "computer_advanced", ( blockPos, blockState ) -> new TileComputer( ModBlockEntities.COMPUTER_ADVANCED, blockPos, blockState, ComputerFamily.ADVANCED ) );
+
+        public static final BlockEntityType<TileCommandComputer> COMPUTER_COMMAND =
+            ofBlock( ModBlocks.COMPUTER_COMMAND, "computer_command", ( blockPos, blockState ) -> new TileCommandComputer( ModBlockEntities.COMPUTER_COMMAND, blockPos, blockState ) );
+
+        public static final BlockEntityType<TileTurtle> TURTLE_NORMAL =
+            ofBlock( ModBlocks.TURTLE_NORMAL, "turtle_normal", ( blockPos, blockState ) -> new TileTurtle( ModBlockEntities.TURTLE_NORMAL, blockPos, blockState, ComputerFamily.NORMAL ) );
+
+        public static final BlockEntityType<TileTurtle> TURTLE_ADVANCED =
+            ofBlock( ModBlocks.TURTLE_ADVANCED, "turtle_advanced", ( blockPos, blockState ) -> new TileTurtle( ModBlockEntities.TURTLE_ADVANCED, blockPos, blockState, ComputerFamily.ADVANCED ) );
+
+        public static final BlockEntityType<TileSpeaker> SPEAKER =
+            ofBlock( ModBlocks.SPEAKER, "speaker", ( blockPos, blockState ) -> new TileSpeaker( ModBlockEntities.SPEAKER, blockPos, blockState ) );
+
+        public static final BlockEntityType<TileDiskDrive> DISK_DRIVE =
+            ofBlock( ModBlocks.DISK_DRIVE, "disk_drive", ( blockPos, blockState ) -> new TileDiskDrive( ModBlockEntities.DISK_DRIVE, blockPos, blockState ) );
+
+        public static final BlockEntityType<TilePrinter> PRINTER =
+            ofBlock( ModBlocks.PRINTER, "printer", ( blockPos, blockState ) -> new TilePrinter( ModBlockEntities.PRINTER, blockPos, blockState ) );
+
+        public static final BlockEntityType<TileWiredModemFull> WIRED_MODEM_FULL =
+            ofBlock( ModBlocks.WIRED_MODEM_FULL, "wired_modem_full", ( blockPos, blockState ) -> new TileWiredModemFull( ModBlockEntities.WIRED_MODEM_FULL, blockPos, blockState ) );
+
+        public static final BlockEntityType<TileCable> CABLE =
+            ofBlock( ModBlocks.CABLE, "cable", ( blockPos, blockState ) -> new TileCable( ModBlockEntities.CABLE, blockPos, blockState ) );
+
+        public static final BlockEntityType<TileWirelessModem> WIRELESS_MODEM_NORMAL =
+            ofBlock( ModBlocks.WIRELESS_MODEM_NORMAL, "wireless_modem_normal", ( blockPos, blockState ) -> new TileWirelessModem( ModBlockEntities.WIRELESS_MODEM_NORMAL, blockPos, blockState, false ) );
+
+        public static final BlockEntityType<TileWirelessModem> WIRELESS_MODEM_ADVANCED =
+            ofBlock( ModBlocks.WIRELESS_MODEM_ADVANCED, "wireless_modem_advanced", ( blockPos, blockState ) -> new TileWirelessModem( ModBlockEntities.WIRELESS_MODEM_ADVANCED, blockPos, blockState, true ) );
+    }
+
+    public static final class ModItems
+    {
+        private static final CreativeModeTab mainItemGroup = ComputerCraft.MAIN_GROUP;
+
+        public static final ItemComputer COMPUTER_NORMAL =
+            ofBlock( ModBlocks.COMPUTER_NORMAL, ItemComputer::new );
+
+        public static final ItemComputer COMPUTER_ADVANCED =
+            ofBlock( ModBlocks.COMPUTER_ADVANCED, ItemComputer::new );
+
+        public static final ItemComputer COMPUTER_COMMAND =
+            ofBlock( ModBlocks.COMPUTER_COMMAND, ItemComputer::new );
+
+        public static final ItemPocketComputer POCKET_COMPUTER_NORMAL =
+            register( "pocket_computer_normal", new ItemPocketComputer( properties().stacksTo( 1 ), ComputerFamily.NORMAL ) );
+
+        public static final ItemPocketComputer POCKET_COMPUTER_ADVANCED =
+            register( "pocket_computer_advanced", new ItemPocketComputer( properties().stacksTo( 1 ), ComputerFamily.ADVANCED ) );
+
+        public static final ItemTurtle TURTLE_NORMAL =
+            ofBlock( ModBlocks.TURTLE_NORMAL, ItemTurtle::new );
+
+        public static final ItemTurtle TURTLE_ADVANCED =
+            ofBlock( ModBlocks.TURTLE_ADVANCED, ItemTurtle::new );
+
+        public static final ItemDisk DISK =
+            register( "disk", new ItemDisk( properties().stacksTo( 1 ) ) );
+
+        public static final ItemTreasureDisk TREASURE_DISK =
+            register( "treasure_disk", new ItemTreasureDisk( properties().stacksTo( 1 ) ) );
+
+        public static final ItemPrintout PRINTED_PAGE =
+            register( "printed_page", new ItemPrintout( properties().stacksTo( 1 ), ItemPrintout.Type.PAGE ) );
+
+        public static final ItemPrintout PRINTED_PAGES =
+            register( "printed_pages", new ItemPrintout( properties().stacksTo( 1 ), ItemPrintout.Type.PAGES ) );
+
+        public static final ItemPrintout PRINTED_BOOK =
+            register( "printed_book", new ItemPrintout( properties().stacksTo( 1 ), ItemPrintout.Type.BOOK ) );
+
+        public static final BlockItem SPEAKER =
+            ofBlock( ModBlocks.SPEAKER, BlockItem::new );
+
+        public static final BlockItem DISK_DRIVE =
+            ofBlock( ModBlocks.DISK_DRIVE, BlockItem::new );
+
+        public static final BlockItem PRINTER =
+            ofBlock( ModBlocks.PRINTER, BlockItem::new );
+
+        public static final BlockItem MONITOR_NORMAL =
+            ofBlock( ModBlocks.MONITOR_NORMAL, BlockItem::new );
+
+        public static final BlockItem MONITOR_ADVANCED =
+            ofBlock( ModBlocks.MONITOR_ADVANCED, BlockItem::new );
+
+        public static final BlockItem WIRELESS_MODEM_NORMAL =
+            ofBlock( ModBlocks.WIRELESS_MODEM_NORMAL, BlockItem::new );
+
+        public static final BlockItem WIRELESS_MODEM_ADVANCED =
+            ofBlock( ModBlocks.WIRELESS_MODEM_ADVANCED, BlockItem::new );
+
+        public static final BlockItem WIRED_MODEM_FULL =
+            ofBlock( ModBlocks.WIRED_MODEM_FULL, BlockItem::new );
+
+        public static final ItemBlockCable.Cable CABLE =
+            register( "cable", new ItemBlockCable.Cable( ModBlocks.CABLE, properties() ) );
+
+        public static final ItemBlockCable.WiredModem WIRED_MODEM =
+            register( "wired_modem", new ItemBlockCable.WiredModem( ModBlocks.CABLE, properties() ) );
+
+
+        private static <B extends Block, I extends Item> I ofBlock( B parent, BiFunction<B, Item.Properties, I> supplier )
+        {
+            return net.minecraft.core.Registry.register( net.minecraft.core.Registry.ITEM, net.minecraft.core.Registry.BLOCK.getKey( parent ), supplier.apply( parent, properties() ) );
+        }
+
+        private static Item.Properties properties()
+        {
+            return new Item.Properties().tab( mainItemGroup );
+        }
+
+        private static <T extends Item> T register( String id, T item )
+        {
+            return net.minecraft.core.Registry.register( net.minecraft.core.Registry.ITEM, new ResourceLocation( MOD_ID, id ), item );
+        }
+    }
+
+    public static class ModEntities
+    {
+        public static final EntityType<TurtlePlayer> TURTLE_PLAYER =
+            net.minecraft.core.Registry.register( net.minecraft.core.Registry.ENTITY_TYPE, new ResourceLocation( MOD_ID, "turtle_player" ),
+            EntityType.Builder.<TurtlePlayer>createNothing( MobCategory.MISC ).noSave().noSummon().sized( 0, 0 ).build( ComputerCraft.MOD_ID + ":turtle_player" ) );
+    }
+
+    public static class ModContainers
+    {
+        public static final MenuType<ContainerComputerBase> COMPUTER =
+            ContainerData.toType( new ResourceLocation( MOD_ID, "computer" ), ModContainers.COMPUTER, ComputerContainerData::new, ComputerMenuWithoutInventory::new );
+
+        public static final MenuType<ContainerComputerBase> POCKET_COMPUTER =
+            ContainerData.toType( new ResourceLocation( MOD_ID, "pocket_computer" ), ModContainers.POCKET_COMPUTER, ComputerContainerData::new, ComputerMenuWithoutInventory::new );
+
+        public static final MenuType<ContainerComputerBase> POCKET_COMPUTER_NO_TERM =
+            ContainerData.toType( new ResourceLocation( MOD_ID, "pocket_computer_no_term" ), ModContainers.POCKET_COMPUTER_NO_TERM, ComputerContainerData::new, ComputerMenuWithoutInventory::new );
+
+        public static final MenuType<ContainerTurtle> TURTLE =
+            ContainerData.toType( new ResourceLocation( MOD_ID, "turtle" ), ComputerContainerData::new, ContainerTurtle::new );
+
+        public static final MenuType<ContainerDiskDrive> DISK_DRIVE =
+            registerSimple( "disk_drive", ContainerDiskDrive::new );
+
+        public static final MenuType<ContainerPrinter> PRINTER =
+            registerSimple( "printer", ContainerPrinter::new );
+
+        public static final MenuType<ContainerHeldItem> PRINTOUT =
+            ContainerData.toType( new ResourceLocation( MOD_ID, "printout" ), HeldItemContainerData::new, ContainerHeldItem::createPrintout );
+
+        public static final MenuType<ContainerViewComputer> VIEW_COMPUTER =
+            ContainerData.toType( new ResourceLocation( MOD_ID, "view_computer" ), ViewComputerContainerData::new, ContainerViewComputer::new );
+
+        private static <T extends AbstractContainerMenu> MenuType<T> registerSimple( String id, ScreenHandlerRegistry.SimpleClientHandlerFactory<T> function )
+        {
+            return ScreenHandlerRegistry.registerSimple( new ResourceLocation( MOD_ID, id ), function );
+        }
+    }
+
+    public static final class TurtleUpgrades
+    {
+        public static TurtleModem wirelessModemNormal =
+            new TurtleModem( new ResourceLocation( ComputerCraft.MOD_ID, "wireless_modem_normal" ), new ItemStack( ModItems.WIRELESS_MODEM_NORMAL ), false );
+
+        public static TurtleModem wirelessModemAdvanced =
+            new TurtleModem( new ResourceLocation( ComputerCraft.MOD_ID, "wireless_modem_advanced" ), new ItemStack( ModItems.WIRELESS_MODEM_ADVANCED ), true );
+
+        public static TurtleSpeaker speaker =
+            new TurtleSpeaker( new ResourceLocation( ComputerCraft.MOD_ID, "speaker" ), new ItemStack( ModItems.SPEAKER ) );
+
+        public static TurtleCraftingTable craftingTable =
+            new TurtleCraftingTable( new ResourceLocation( "minecraft", "crafting_table" ), new ItemStack( Items.CRAFTING_TABLE ) );
+
+        public static TurtleTool diamondSword =
+            new TurtleTool( new ResourceLocation( "minecraft", "diamond_sword" ), Items.DIAMOND_SWORD, 9.0f, ComputerCraftTags.Blocks.TURTLE_SWORD_BREAKABLE );
+
+        public static TurtleTool diamondShovel =
+            new TurtleTool( new ResourceLocation( "minecraft", "diamond_shovel" ), Items.DIAMOND_SHOVEL, 1.0f, ComputerCraftTags.Blocks.TURTLE_SHOVEL_BREAKABLE );
+
+        public static TurtleTool diamondPickaxe =
+            new TurtleTool( new ResourceLocation( "minecraft", "diamond_pickaxe" ), Items.DIAMOND_PICKAXE, 1.0f, null );
+
+        public static TurtleTool diamondAxe =
+            new TurtleTool( new ResourceLocation( "minecraft", "diamond_axe" ), Items.DIAMOND_AXE, 6.0f, null );
+
+        public static TurtleTool diamondHoe =
+            new TurtleTool( new ResourceLocation( "minecraft", "diamond_hoe" ), Items.DIAMOND_HOE, 1.0f, ComputerCraftTags.Blocks.TURTLE_HOE_BREAKABLE );
+
+        public static TurtleTool netheritePickaxe =
+            new TurtleTool( new ResourceLocation( "minecraft", "netherite_pickaxe" ), Items.NETHERITE_PICKAXE, 1.0f, null );
+
+        public static void registerTurtleUpgrades()
+        {
+            ComputerCraftAPI.registerTurtleUpgrade( wirelessModemNormal );
+            ComputerCraftAPI.registerTurtleUpgrade( wirelessModemAdvanced );
+            ComputerCraftAPI.registerTurtleUpgrade( speaker );
+            ComputerCraftAPI.registerTurtleUpgrade( craftingTable );
+
+            ComputerCraftAPI.registerTurtleUpgrade( diamondSword );
+            ComputerCraftAPI.registerTurtleUpgrade( diamondShovel );
+            ComputerCraftAPI.registerTurtleUpgrade( diamondPickaxe );
+            ComputerCraftAPI.registerTurtleUpgrade( diamondAxe );
+            ComputerCraftAPI.registerTurtleUpgrade( diamondHoe );
+            ComputerCraftAPI.registerTurtleUpgrade( netheritePickaxe );
+        }
+    }
+
+    public static final class PocketUpgrades
+    {
+        public static PocketModem wirelessModemNormal = new PocketModem( new ResourceLocation( ComputerCraft.MOD_ID, "wireless_modem_normal" ), new ItemStack( ModItems.WIRELESS_MODEM_NORMAL ), false );
+
+        public static PocketModem wirelessModemAdvanced = new PocketModem( new ResourceLocation( ComputerCraft.MOD_ID, "wireless_modem_advanced" ), new ItemStack( ModItems.WIRELESS_MODEM_ADVANCED ), true );
+
+        public static PocketSpeaker speaker = new PocketSpeaker( new ResourceLocation( ComputerCraft.MOD_ID, "speaker" ), new ItemStack( ModItems.SPEAKER ) );
+
+        public static void registerPocketUpgrades()
+        {
+            ComputerCraftAPI.registerPocketUpgrade( wirelessModemNormal );
+            ComputerCraftAPI.registerPocketUpgrade( wirelessModemAdvanced );
+            ComputerCraftAPI.registerPocketUpgrade( speaker );
+        }
+    }
+
+
+}

src/main/java/dan200/computercraft/shared/TurtleUpgrades.java

@@ -98,17 +98,17 @@ public final class TurtleUpgrades
         {
             vanilla = new ITurtleUpgrade[] {
                 // ComputerCraft upgrades
-                ComputerCraftRegistry.TurtleUpgrades.wirelessModemNormal,
-                ComputerCraftRegistry.TurtleUpgrades.wirelessModemAdvanced,
-                ComputerCraftRegistry.TurtleUpgrades.speaker,
+                Registry.TurtleUpgrades.wirelessModemNormal,
+                Registry.TurtleUpgrades.wirelessModemAdvanced,
+                Registry.TurtleUpgrades.speaker,
 
                 // Vanilla Minecraft upgrades
-                ComputerCraftRegistry.TurtleUpgrades.diamondPickaxe,
-                ComputerCraftRegistry.TurtleUpgrades.diamondAxe,
-                ComputerCraftRegistry.TurtleUpgrades.diamondSword,
-                ComputerCraftRegistry.TurtleUpgrades.diamondShovel,
-                ComputerCraftRegistry.TurtleUpgrades.diamondHoe,
-                ComputerCraftRegistry.TurtleUpgrades.craftingTable,
+                Registry.TurtleUpgrades.diamondPickaxe,
+                Registry.TurtleUpgrades.diamondAxe,
+                Registry.TurtleUpgrades.diamondSword,
+                Registry.TurtleUpgrades.diamondShovel,
+                Registry.TurtleUpgrades.diamondHoe,
+                Registry.TurtleUpgrades.craftingTable,
             };
         }
 

src/main/java/dan200/computercraft/shared/command/ClientCommands.java

@@ -6,7 +6,9 @@
 package dan200.computercraft.shared.command;
 
 import dan200.computercraft.shared.util.IDAssigner;
+import me.shedaniel.cloth.api.utils.v1.GameInstanceUtils;
 import net.minecraft.Util;
+import net.minecraft.server.MinecraftServer;
 
 import java.io.File;
 
@@ -28,6 +30,9 @@ public final class ClientCommands
         // Emulate the command on the client side
         if( message.startsWith( OPEN_COMPUTER ) )
         {
+            MinecraftServer server = GameInstanceUtils.getServer();
+            if( server == null || server.isDedicatedServer() ) return false;
+
             String idStr = message.substring( OPEN_COMPUTER.length() ).trim();
             int id;
             try
@@ -36,7 +41,7 @@ public final class ClientCommands
             }
             catch( NumberFormatException ignore )
             {
-                return true;
+                return false;
             }
 
             File file = new File( IDAssigner.getDir(), "computer/" + id );

src/main/java/dan200/computercraft/shared/command/CommandComputerCraft.java

@@ -26,6 +26,7 @@ import net.fabricmc.fabric.api.screenhandler.v1.ExtendedScreenHandlerFactory;
 import net.minecraft.commands.CommandSourceStack;
 import net.minecraft.core.BlockPos;
 import net.minecraft.network.FriendlyByteBuf;
+import net.minecraft.network.chat.Component;
 import net.minecraft.network.chat.MutableComponent;
 import net.minecraft.network.chat.TextComponent;
 import net.minecraft.network.chat.TranslatableComponent;
@@ -82,15 +83,15 @@ public final class CommandComputerCraft
                     BlockPos pos = new BlockPos( source.getPosition() );
 
                     computers.sort( ( a, b ) -> {
-                        if( a.getWorld() == b.getWorld() && a.getWorld() == world )
+                        if( a.getLevel() == b.getLevel() && a.getLevel() == world )
                         {
                             return Double.compare( a.getPosition().distSqr( pos ), b.getPosition().distSqr( pos ) );
                         }
-                        else if( a.getWorld() == world )
+                        else if( a.getLevel() == world )
                         {
                             return -1;
                         }
-                        else if( b.getWorld() == world )
+                        else if( b.getLevel() == world )
                         {
                             return 1;
                         }
@@ -171,15 +172,14 @@ public final class CommandComputerCraft
                 .arg( "computer", oneComputer() )
                 .executes( context -> {
                     ServerComputer computer = getComputerArgument( context, "computer" );
-                    Level world = computer.getWorld();
+                    Level world = computer.getLevel();
                     BlockPos pos = computer.getPosition();
 
                     if( world == null || pos == null ) throw TP_NOT_THERE.create();
 
                     Entity entity = context.getSource().getEntityOrException();
-                    if( !(entity instanceof ServerPlayer) ) throw TP_NOT_PLAYER.create();
+                    if( !(entity instanceof ServerPlayer player) ) throw TP_NOT_PLAYER.create();
 
-                    ServerPlayer player = (ServerPlayer) entity;
                     if( player.getCommandSenderWorld() == world )
                     {
                         player.connection.teleport(
@@ -236,7 +236,7 @@ public final class CommandComputerCraft
 
                         @Nonnull
                         @Override
-                        public MutableComponent getDisplayName()
+                        public Component getDisplayName()
                         {
                             return new TranslatableComponent( "gui.computercraft.view_computer" );
                         }
@@ -292,7 +292,7 @@ public final class CommandComputerCraft
         );
     }
 
-    private static MutableComponent linkComputer( CommandSourceStack source, ServerComputer serverComputer, int computerId )
+    private static Component linkComputer( CommandSourceStack source, ServerComputer serverComputer, int computerId )
     {
         MutableComponent out = new TextComponent( "" );
 
@@ -333,14 +333,14 @@ public final class CommandComputerCraft
 
         if( UserLevel.OWNER.test( source ) && isPlayer( source ) )
         {
-            MutableComponent linkPath = linkStorage( computerId );
+            Component linkPath = linkStorage( computerId );
             if( linkPath != null ) out.append( " " ).append( linkPath );
         }
 
         return out;
     }
 
-    private static MutableComponent linkPosition( CommandSourceStack context, ServerComputer computer )
+    private static Component linkPosition( CommandSourceStack context, ServerComputer computer )
     {
         if( UserLevel.OP.test( context ) )
         {
@@ -356,7 +356,7 @@ public final class CommandComputerCraft
         }
     }
 
-    private static MutableComponent linkStorage( int id )
+    private static Component linkStorage( int id )
     {
         File file = new File( IDAssigner.getDir(), "computer/" + id );
         if( !file.isDirectory() ) return null;
@@ -398,7 +398,7 @@ public final class CommandComputerCraft
 
         timings.sort( Comparator.<ComputerTracker, Long>comparing( x -> x.get( sortField ) ).reversed() );
 
-        MutableComponent[] headers = new MutableComponent[1 + fields.size()];
+        Component[] headers = new Component[1 + fields.size()];
         headers[0] = translate( "commands.computercraft.track.dump.computer" );
         for( int i = 0; i < fields.size(); i++ ) headers[i + 1] = translate( fields.get( i ).translationKey() );
         TableBuilder table = new TableBuilder( TRACK_ID, headers );
@@ -408,9 +408,9 @@ public final class CommandComputerCraft
             Computer computer = entry.getComputer();
             ServerComputer serverComputer = computer == null ? null : lookup.get( computer );
 
-            MutableComponent computerComponent = linkComputer( source, serverComputer, entry.getComputerId() );
+            Component computerComponent = linkComputer( source, serverComputer, entry.getComputerId() );
 
-            MutableComponent[] row = new MutableComponent[1 + fields.size()];
+            Component[] row = new Component[1 + fields.size()];
             row[0] = computerComponent;
             for( int i = 0; i < fields.size(); i++ ) row[i + 1] = text( entry.getFormatted( fields.get( i ) ) );
             table.row( row );

src/main/java/dan200/computercraft/shared/command/CommandUtils.java

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.shared.command;
 
 import com.mojang.brigadier.context.CommandContext;
@@ -27,12 +26,13 @@ public final class CommandUtils
     public static boolean isPlayer( CommandSourceStack output )
     {
         Entity sender = output.getEntity();
-        return sender instanceof ServerPlayer && !(sender instanceof FakePlayer) && ((ServerPlayer) sender).connection != null;
+        return sender instanceof ServerPlayer
+            && !(sender instanceof FakePlayer)
+            && ((ServerPlayer) sender).connection != null;
     }
 
     @SuppressWarnings( "unchecked" )
-    public static CompletableFuture<Suggestions> suggestOnServer( CommandContext<?> context, SuggestionsBuilder builder,
-                                                                  Function<CommandContext<CommandSourceStack>, CompletableFuture<Suggestions>> supplier )
+    public static CompletableFuture<Suggestions> suggestOnServer( CommandContext<?> context, SuggestionsBuilder builder, Function<CommandContext<CommandSourceStack>, CompletableFuture<Suggestions>> supplier )
     {
         Object source = context.getSource();
         if( !(source instanceof SharedSuggestionProvider) )
@@ -49,26 +49,21 @@ public final class CommandUtils
         }
     }
 
-    public static <T> CompletableFuture<Suggestions> suggest( SuggestionsBuilder builder, T[] candidates, Function<T, String> toString )
-    {
-        return suggest( builder, Arrays.asList( candidates ), toString );
-    }
-
     public static <T> CompletableFuture<Suggestions> suggest( SuggestionsBuilder builder, Iterable<T> candidates, Function<T, String> toString )
     {
-        String remaining = builder.getRemaining()
-            .toLowerCase( Locale.ROOT );
+        String remaining = builder.getRemaining().toLowerCase( Locale.ROOT );
         for( T choice : candidates )
         {
             String name = toString.apply( choice );
-            if( !name.toLowerCase( Locale.ROOT )
-                .startsWith( remaining ) )
-            {
-                continue;
-            }
+            if( !name.toLowerCase( Locale.ROOT ).startsWith( remaining ) ) continue;
             builder.suggest( name );
         }
 
         return builder.buildFuture();
     }
+
+    public static <T> CompletableFuture<Suggestions> suggest( SuggestionsBuilder builder, T[] candidates, Function<T, String> toString )
+    {
+        return suggest( builder, Arrays.asList( candidates ), toString );
+    }
 }

src/main/java/dan200/computercraft/shared/command/Exceptions.java

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.shared.command;
 
 import com.mojang.brigadier.exceptions.Dynamic2CommandExceptionType;
@@ -17,12 +16,15 @@ public final class Exceptions
     public static final Dynamic2CommandExceptionType COMPUTER_ARG_MANY = translated2( "argument.computercraft.computer.many_matching" );
 
     public static final DynamicCommandExceptionType TRACKING_FIELD_ARG_NONE = translated1( "argument.computercraft.tracking_field.no_field" );
-    public static final SimpleCommandExceptionType ARGUMENT_EXPECTED = translated( "argument.computercraft.argument_expected" );
+
     static final SimpleCommandExceptionType NOT_TRACKING_EXCEPTION = translated( "commands.computercraft.track.stop.not_enabled" );
     static final SimpleCommandExceptionType NO_TIMINGS_EXCEPTION = translated( "commands.computercraft.track.dump.no_timings" );
+
     static final SimpleCommandExceptionType TP_NOT_THERE = translated( "commands.computercraft.tp.not_there" );
     static final SimpleCommandExceptionType TP_NOT_PLAYER = translated( "commands.computercraft.tp.not_player" );
 
+    public static final SimpleCommandExceptionType ARGUMENT_EXPECTED = translated( "argument.computercraft.argument_expected" );
+
     private static SimpleCommandExceptionType translated( String key )
     {
         return new SimpleCommandExceptionType( new TranslatableComponent( key ) );

src/main/java/dan200/computercraft/shared/command/UserLevel.java

@@ -67,6 +67,6 @@ public enum UserLevel implements Predicate<CommandSourceStack>
         Entity sender = source.getEntity();
         return server.isDedicatedServer()
             ? source.getEntity() == null && source.hasPermission( 4 ) && source.getTextName().equals( "Server" )
-            : sender instanceof Player && ((Player) sender).getGameProfile().getName().equalsIgnoreCase( server.getServerModName() );
+            : sender instanceof Player player && player.getGameProfile().getName().equalsIgnoreCase( server.getServerModName() );
     }
 }

src/main/java/dan200/computercraft/shared/command/arguments/ArgumentSerializers.java

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.shared.command.arguments;
 
 import com.mojang.brigadier.arguments.ArgumentType;
@@ -15,17 +14,10 @@ import net.minecraft.resources.ResourceLocation;
 
 public final class ArgumentSerializers
 {
-    public static void register()
+    @SuppressWarnings( "unchecked" )
+    private static <T extends ArgumentType<?>> void registerUnsafe( ResourceLocation id, Class<T> type, ArgumentSerializer<?> serializer )
     {
-        register( new ResourceLocation( ComputerCraft.MOD_ID, "tracking_field" ), TrackingFieldArgumentType.trackingField() );
-        register( new ResourceLocation( ComputerCraft.MOD_ID, "computer" ), ComputerArgumentType.oneComputer() );
-        register( new ResourceLocation( ComputerCraft.MOD_ID, "computers" ), ComputersArgumentType.class, new ComputersArgumentType.Serializer() );
-        registerUnsafe( new ResourceLocation( ComputerCraft.MOD_ID, "repeat" ), RepeatArgumentType.class, new RepeatArgumentType.Serializer() );
-    }
-
-    private static <T extends ArgumentType<?>> void register( ResourceLocation id, T instance )
-    {
-        registerUnsafe( id, instance.getClass(), new EmptyArgumentSerializer<>( () -> instance ) );
+        ArgumentTypes.register( id.toString(), type, (ArgumentSerializer<T>) serializer );
     }
 
     private static <T extends ArgumentType<?>> void register( ResourceLocation id, Class<T> type, ArgumentSerializer<T> serializer )
@@ -33,9 +25,16 @@ public final class ArgumentSerializers
         ArgumentTypes.register( id.toString(), type, serializer );
     }
 
-    @SuppressWarnings( "unchecked" )
-    private static <T extends ArgumentType<?>> void registerUnsafe( ResourceLocation id, Class<T> type, ArgumentSerializer<?> serializer )
+    private static <T extends ArgumentType<?>> void register( ResourceLocation id, T instance )
     {
-        ArgumentTypes.register( id.toString(), type, (ArgumentSerializer<T>) serializer );
+        registerUnsafe( id, instance.getClass(), new EmptyArgumentSerializer<>( () -> instance ) );
+    }
+
+    public static void register()
+    {
+        register( new ResourceLocation( ComputerCraft.MOD_ID, "tracking_field" ), TrackingFieldArgumentType.trackingField() );
+        register( new ResourceLocation( ComputerCraft.MOD_ID, "computer" ), ComputerArgumentType.oneComputer() );
+        register( new ResourceLocation( ComputerCraft.MOD_ID, "computers" ), ComputersArgumentType.class, new ComputersArgumentType.Serializer() );
+        registerUnsafe( new ResourceLocation( ComputerCraft.MOD_ID, "repeat" ), RepeatArgumentType.class, new RepeatArgumentType.Serializer() );
     }
 }

src/main/java/dan200/computercraft/shared/command/arguments/ChoiceArgumentType.java

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.shared.command.arguments;
 
 import com.mojang.brigadier.Message;
@@ -43,10 +42,7 @@ public abstract class ChoiceArgumentType<T> implements ArgumentType<T>
         for( T choice : choices )
         {
             String choiceName = this.name.apply( choice );
-            if( name.equals( choiceName ) )
-            {
-                return choice;
-            }
+            if( name.equals( choiceName ) ) return choice;
         }
 
         reader.setCursor( start );
@@ -56,16 +52,11 @@ public abstract class ChoiceArgumentType<T> implements ArgumentType<T>
     @Override
     public <S> CompletableFuture<Suggestions> listSuggestions( CommandContext<S> context, SuggestionsBuilder builder )
     {
-        String remaining = builder.getRemaining()
-            .toLowerCase( Locale.ROOT );
+        String remaining = builder.getRemaining().toLowerCase( Locale.ROOT );
         for( T choice : choices )
         {
             String name = this.name.apply( choice );
-            if( !name.toLowerCase( Locale.ROOT )
-                .startsWith( remaining ) )
-            {
-                continue;
-            }
+            if( !name.toLowerCase( Locale.ROOT ).startsWith( remaining ) ) continue;
             builder.suggest( name, tooltip.apply( choice ) );
         }
 
@@ -76,10 +67,7 @@ public abstract class ChoiceArgumentType<T> implements ArgumentType<T>
     public Collection<String> getExamples()
     {
         List<String> items = choices instanceof Collection<?> ? new ArrayList<>( ((Collection<T>) choices).size() ) : new ArrayList<>();
-        for( T choice : choices )
-        {
-            items.add( name.apply( choice ) );
-        }
+        for( T choice : choices ) items.add( name.apply( choice ) );
         items.sort( Comparator.naturalOrder() );
         return items;
     }

src/main/java/dan200/computercraft/shared/command/arguments/ComputerArgumentType.java

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.shared.command.arguments;
 
 import com.mojang.brigadier.StringReader;
@@ -25,10 +24,6 @@ public final class ComputerArgumentType implements ArgumentType<ComputerArgument
 {
     private static final ComputerArgumentType INSTANCE = new ComputerArgumentType();
 
-    private ComputerArgumentType()
-    {
-    }
-
     public static ComputerArgumentType oneComputer()
     {
         return INSTANCE;
@@ -36,27 +31,24 @@ public final class ComputerArgumentType implements ArgumentType<ComputerArgument
 
     public static ServerComputer getComputerArgument( CommandContext<CommandSourceStack> context, String name ) throws CommandSyntaxException
     {
-        return context.getArgument( name, ComputerSupplier.class )
-            .unwrap( context.getSource() );
+        return context.getArgument( name, ComputerSupplier.class ).unwrap( context.getSource() );
+    }
+
+    private ComputerArgumentType()
+    {
     }
 
     @Override
     public ComputerSupplier parse( StringReader reader ) throws CommandSyntaxException
     {
         int start = reader.getCursor();
-        ComputersSupplier supplier = ComputersArgumentType.someComputers()
-            .parse( reader );
-        String selector = reader.getString()
-            .substring( start, reader.getCursor() );
+        ComputersSupplier supplier = ComputersArgumentType.someComputers().parse( reader );
+        String selector = reader.getString().substring( start, reader.getCursor() );
 
         return s -> {
             Collection<ServerComputer> computers = supplier.unwrap( s );
 
-            if( computers.size() == 1 )
-            {
-                return computers.iterator()
-                    .next();
-            }
+            if( computers.size() == 1 ) return computers.iterator().next();
 
             StringBuilder builder = new StringBuilder();
             boolean first = true;
@@ -84,15 +76,13 @@ public final class ComputerArgumentType implements ArgumentType<ComputerArgument
     @Override
     public <S> CompletableFuture<Suggestions> listSuggestions( CommandContext<S> context, SuggestionsBuilder builder )
     {
-        return ComputersArgumentType.someComputers()
-            .listSuggestions( context, builder );
+        return ComputersArgumentType.someComputers().listSuggestions( context, builder );
     }
 
     @Override
     public Collection<String> getExamples()
     {
-        return ComputersArgumentType.someComputers()
-            .getExamples();
+        return ComputersArgumentType.someComputers().getExamples();
     }
 
     @FunctionalInterface

src/main/java/dan200/computercraft/shared/command/arguments/ComputersArgumentType.java

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.shared.command.arguments;
 
 import com.google.gson.JsonObject;
@@ -36,13 +35,9 @@ public final class ComputersArgumentType implements ArgumentType<ComputersArgume
     private static final ComputersArgumentType MANY = new ComputersArgumentType( false );
     private static final ComputersArgumentType SOME = new ComputersArgumentType( true );
 
-    private static final List<String> EXAMPLES = Arrays.asList( "0", "#0", "@Label", "~Advanced" );
-    private final boolean requireSome;
-
-    private ComputersArgumentType( boolean requireSome )
-    {
-        this.requireSome = requireSome;
-    }
+    private static final List<String> EXAMPLES = Arrays.asList(
+        "0", "#0", "@Label", "~Advanced"
+    );
 
     public static ComputersArgumentType manyComputers()
     {
@@ -56,18 +51,14 @@ public final class ComputersArgumentType implements ArgumentType<ComputersArgume
 
     public static Collection<ServerComputer> getComputersArgument( CommandContext<CommandSourceStack> context, String name ) throws CommandSyntaxException
     {
-        return context.getArgument( name, ComputersSupplier.class )
-            .unwrap( context.getSource() );
+        return context.getArgument( name, ComputersSupplier.class ).unwrap( context.getSource() );
     }
 
-    public static Set<ServerComputer> unwrap( CommandSourceStack source, Collection<ComputersSupplier> suppliers ) throws CommandSyntaxException
+    private final boolean requireSome;
+
+    private ComputersArgumentType( boolean requireSome )
     {
-        Set<ServerComputer> computers = new HashSet<>();
-        for( ComputersSupplier supplier : suppliers )
-        {
-            computers.addAll( supplier.unwrap( source ) );
-        }
-        return computers;
+        this.requireSome = requireSome;
     }
 
     @Override
@@ -86,9 +77,7 @@ public final class ComputersArgumentType implements ArgumentType<ComputersArgume
         {
             reader.skip();
             String family = reader.readUnquotedString();
-            computers = getComputers( x -> x.getFamily()
-                .name()
-                .equalsIgnoreCase( family ) );
+            computers = getComputers( x -> x.getFamily().name().equalsIgnoreCase( family ) );
         }
         else if( kind == '#' )
         {
@@ -107,14 +96,10 @@ public final class ComputersArgumentType implements ArgumentType<ComputersArgume
 
         if( requireSome )
         {
-            String selector = reader.getString()
-                .substring( start, reader.getCursor() );
+            String selector = reader.getString().substring( start, reader.getCursor() );
             return source -> {
                 Collection<ServerComputer> matched = computers.unwrap( source );
-                if( matched.isEmpty() )
-                {
-                    throw COMPUTER_ARG_NONE.create( selector );
-                }
+                if( matched.isEmpty() ) throw COMPUTER_ARG_NONE.create( selector );
                 return matched;
             };
         }
@@ -169,8 +154,7 @@ public final class ComputersArgumentType implements ArgumentType<ComputersArgume
         for( ServerComputer computer : ComputerCraft.serverComputerRegistry.getComputers() )
         {
             String converted = renderer.apply( computer );
-            if( converted != null && converted.toLowerCase( Locale.ROOT )
-                .startsWith( remaining ) )
+            if( converted != null && converted.toLowerCase( Locale.ROOT ).startsWith( remaining ) )
             {
                 builder.suggest( converted );
             }
@@ -179,16 +163,12 @@ public final class ComputersArgumentType implements ArgumentType<ComputersArgume
 
     private static ComputersSupplier getComputers( Predicate<ServerComputer> predicate )
     {
-        return s -> Collections.unmodifiableList( ComputerCraft.serverComputerRegistry.getComputers()
+        return s -> Collections.unmodifiableList( ComputerCraft.serverComputerRegistry
+            .getComputers()
             .stream()
             .filter( predicate )
-            .collect( Collectors.toList() ) );
-    }
-
-    @FunctionalInterface
-    public interface ComputersSupplier
-    {
-        Collection<ServerComputer> unwrap( CommandSourceStack source ) throws CommandSyntaxException;
+            .collect( Collectors.toList() )
+        );
     }
 
     public static class Serializer implements ArgumentSerializer<ComputersArgumentType>
@@ -213,4 +193,17 @@ public final class ComputersArgumentType implements ArgumentType<ComputersArgume
             json.addProperty( "requireSome", arg.requireSome );
         }
     }
+
+    @FunctionalInterface
+    public interface ComputersSupplier
+    {
+        Collection<ServerComputer> unwrap( CommandSourceStack source ) throws CommandSyntaxException;
+    }
+
+    public static Set<ServerComputer> unwrap( CommandSourceStack source, Collection<ComputersSupplier> suppliers ) throws CommandSyntaxException
+    {
+        Set<ServerComputer> computers = new HashSet<>();
+        for( ComputersSupplier supplier : suppliers ) computers.addAll( supplier.unwrap( source ) );
+        return computers;
+    }
 }

src/main/java/dan200/computercraft/shared/command/arguments/RepeatArgumentType.java

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.shared.command.arguments;
 
 import com.google.gson.JsonObject;
@@ -32,8 +31,8 @@ import java.util.function.BiConsumer;
 /**
  * Reads one argument multiple times.
  *
- * Note that this must be the last element in an argument chain: in order to improve the quality of error messages, we will always try to consume another
- * argument while there is input remaining.
+ * Note that this must be the last element in an argument chain: in order to improve the quality of error messages,
+ * we will always try to consume another argument while there is input remaining.
  *
  * One problem with how parsers function, is that they must consume some input: and thus we
  *
@@ -73,10 +72,7 @@ public final class RepeatArgumentType<T, U> implements ArgumentType<List<T>>
         while( true )
         {
             reader.skipWhitespace();
-            if( !reader.canRead() )
-            {
-                break;
-            }
+            if( !reader.canRead() ) break;
 
             int startParse = reader.getCursor();
             appender.accept( out, child.parse( reader ) );
@@ -91,10 +87,7 @@ public final class RepeatArgumentType<T, U> implements ArgumentType<List<T>>
         // Note that each child may return an empty list, we just require that some actual input
         // was consumed.
         // We should probably review that this is sensible in the future.
-        if( !hadSome )
-        {
-            throw some.createWithContext( reader );
-        }
+        if( !hadSome ) throw some.createWithContext( reader );
 
         return Collections.unmodifiableList( out );
     }
@@ -118,10 +111,7 @@ public final class RepeatArgumentType<T, U> implements ArgumentType<List<T>>
 
             int cursor = reader.getCursor();
             reader.skipWhitespace();
-            if( cursor == reader.getCursor() )
-            {
-                break;
-            }
+            if( cursor == reader.getCursor() ) break;
             previous = reader.getCursor();
         }
 
@@ -147,10 +137,7 @@ public final class RepeatArgumentType<T, U> implements ArgumentType<List<T>>
 
         @Nonnull
         @Override
-        @SuppressWarnings( {
-            "unchecked",
-            "rawtypes"
-        } )
+        @SuppressWarnings( { "unchecked", "rawtypes" } )
         public RepeatArgumentType<?, ?> deserializeFromNetwork( @Nonnull FriendlyByteBuf buf )
         {
             boolean isList = buf.readBoolean();
@@ -170,12 +157,8 @@ public final class RepeatArgumentType<T, U> implements ArgumentType<List<T>>
 
         private static Component getMessage( RepeatArgumentType<?, ?> arg )
         {
-            Message message = arg.some.create()
-                .getRawMessage();
-            if( message instanceof Component )
-            {
-                return (Component) message;
-            }
+            Message message = arg.some.create().getRawMessage();
+            if( message instanceof Component ) return (Component) message;
             return new TextComponent( message.getString() );
         }
     }

src/main/java/dan200/computercraft/shared/command/arguments/TrackingFieldArgumentType.java

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.shared.command.arguments;
 
 import dan200.computercraft.core.tracking.TrackingField;
@@ -17,8 +16,7 @@ public final class TrackingFieldArgumentType extends ChoiceArgumentType<Tracking
 
     private TrackingFieldArgumentType()
     {
-        super( TrackingField.fields()
-            .values(), TrackingField::id, x -> translate( x.translationKey() ), Exceptions.TRACKING_FIELD_ARG_NONE );
+        super( TrackingField.fields().values(), TrackingField::id, x -> translate( x.translationKey() ), Exceptions.TRACKING_FIELD_ARG_NONE );
     }
 
     public static TrackingFieldArgumentType trackingField()

src/main/java/dan200/computercraft/shared/command/builder/CommandBuilder.java

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.shared.command.builder;
 
 import com.mojang.brigadier.Command;
@@ -25,13 +24,14 @@ import static dan200.computercraft.shared.command.Exceptions.ARGUMENT_EXPECTED;
 import static dan200.computercraft.shared.command.builder.HelpingArgumentBuilder.literal;
 
 /**
- * An alternative way of building command nodes, so one does not have to nest. {@link ArgumentBuilder#then(CommandNode)}s.
+ * An alternative way of building command nodes, so one does not have to nest.
+ * {@link ArgumentBuilder#then(CommandNode)}s.
  *
  * @param <S> The command source we consume.
  */
 public class CommandBuilder<S> implements CommandNodeBuilder<S, Command<S>>
 {
-    private List<ArgumentBuilder<S, ?>> args = new ArrayList<>();
+    private final List<ArgumentBuilder<S, ?>> args = new ArrayList<>();
     private Predicate<S> requires;
 
     public static CommandBuilder<CommandSourceStack> args()
@@ -58,34 +58,38 @@ public class CommandBuilder<S> implements CommandNodeBuilder<S, Command<S>>
         return this;
     }
 
-    public <T> CommandNodeBuilder<S, ArgCommand<S, List<T>>> argManyValue( String name, ArgumentType<T> type, T defaultValue )
-    {
-        return argManyValue( name, type, Collections.singletonList( defaultValue ) );
-    }
-
     public <T> CommandNodeBuilder<S, ArgCommand<S, List<T>>> argManyValue( String name, ArgumentType<T> type, List<T> empty )
     {
         return argMany( name, type, () -> empty );
     }
 
+    public <T> CommandNodeBuilder<S, ArgCommand<S, List<T>>> argManyValue( String name, ArgumentType<T> type, T defaultValue )
+    {
+        return argManyValue( name, type, Collections.singletonList( defaultValue ) );
+    }
+
     public <T> CommandNodeBuilder<S, ArgCommand<S, List<T>>> argMany( String name, ArgumentType<T> type, Supplier<List<T>> empty )
     {
         return argMany( name, RepeatArgumentType.some( type, ARGUMENT_EXPECTED ), empty );
     }
 
+    public <T> CommandNodeBuilder<S, ArgCommand<S, List<T>>> argManyFlatten( String name, ArgumentType<List<T>> type, Supplier<List<T>> empty )
+    {
+        return argMany( name, RepeatArgumentType.someFlat( type, ARGUMENT_EXPECTED ), empty );
+    }
+
     private <T, U> CommandNodeBuilder<S, ArgCommand<S, List<T>>> argMany( String name, RepeatArgumentType<T, ?> type, Supplier<List<T>> empty )
     {
-        if( args.isEmpty() )
-        {
-            throw new IllegalStateException( "Cannot have empty arg chain builder" );
-        }
+        if( args.isEmpty() ) throw new IllegalStateException( "Cannot have empty arg chain builder" );
 
         return command -> {
             // The node for no arguments
             ArgumentBuilder<S, ?> tail = tail( ctx -> command.run( ctx, empty.get() ) );
 
             // The node for one or more arguments
-            ArgumentBuilder<S, ?> moreArg = RequiredArgumentBuilder.<S, List<T>>argument( name, type ).executes( ctx -> command.run( ctx, getList( ctx, name ) ) );
+            ArgumentBuilder<S, ?> moreArg = RequiredArgumentBuilder
+                .<S, List<T>>argument( name, type )
+                .executes( ctx -> command.run( ctx, getList( ctx, name ) ) );
 
             // Chain all of them together!
             tail.then( moreArg );
@@ -93,46 +97,31 @@ public class CommandBuilder<S> implements CommandNodeBuilder<S, Command<S>>
         };
     }
 
-    private ArgumentBuilder<S, ?> tail( Command<S> command )
-    {
-        ArgumentBuilder<S, ?> defaultTail = args.get( args.size() - 1 );
-        defaultTail.executes( command );
-        if( requires != null )
-        {
-            defaultTail.requires( requires );
-        }
-        return defaultTail;
-    }
-
     @SuppressWarnings( "unchecked" )
     private static <T> List<T> getList( CommandContext<?> context, String name )
     {
         return (List<T>) context.getArgument( name, List.class );
     }
 
-    private CommandNode<S> link( ArgumentBuilder<S, ?> tail )
-    {
-        for( int i = args.size() - 2; i >= 0; i-- )
-        {
-            tail = args.get( i )
-                .then( tail );
-        }
-        return tail.build();
-    }
-
-    public <T> CommandNodeBuilder<S, ArgCommand<S, List<T>>> argManyFlatten( String name, ArgumentType<List<T>> type, Supplier<List<T>> empty )
-    {
-        return argMany( name, RepeatArgumentType.someFlat( type, ARGUMENT_EXPECTED ), empty );
-    }
-
     @Override
     public CommandNode<S> executes( Command<S> command )
     {
-        if( args.isEmpty() )
-        {
-            throw new IllegalStateException( "Cannot have empty arg chain builder" );
-        }
+        if( args.isEmpty() ) throw new IllegalStateException( "Cannot have empty arg chain builder" );
 
         return link( tail( command ) );
     }
+
+    private ArgumentBuilder<S, ?> tail( Command<S> command )
+    {
+        ArgumentBuilder<S, ?> defaultTail = args.get( args.size() - 1 );
+        defaultTail.executes( command );
+        if( requires != null ) defaultTail.requires( requires );
+        return defaultTail;
+    }
+
+    private CommandNode<S> link( ArgumentBuilder<S, ?> tail )
+    {
+        for( int i = args.size() - 2; i >= 0; i-- ) tail = args.get( i ).then( tail );
+        return tail.build();
+    }
 }

src/main/java/dan200/computercraft/shared/command/builder/HelpingArgumentBuilder.java

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.shared.command.builder;
 
 import com.mojang.brigadier.Command;
@@ -28,14 +27,11 @@ import static dan200.computercraft.shared.command.text.ChatHelpers.coloured;
 import static dan200.computercraft.shared.command.text.ChatHelpers.translate;
 
 /**
- * An alternative to {@link LiteralArgumentBuilder} which also provides a {@code /... help} command, and defaults to that command when no arguments are
- * given.
+ * An alternative to {@link LiteralArgumentBuilder} which also provides a {@code /... help} command, and defaults
+ * to that command when no arguments are given.
  */
 public final class HelpingArgumentBuilder extends LiteralArgumentBuilder<CommandSourceStack>
 {
-    private static final ChatFormatting HEADER = ChatFormatting.LIGHT_PURPLE;
-    private static final ChatFormatting SYNOPSIS = ChatFormatting.AQUA;
-    private static final ChatFormatting NAME = ChatFormatting.GREEN;
     private final Collection<HelpingArgumentBuilder> children = new ArrayList<>();
 
     private HelpingArgumentBuilder( String literal )
@@ -48,69 +44,16 @@ public final class HelpingArgumentBuilder extends LiteralArgumentBuilder<Command
         return new HelpingArgumentBuilder( literal );
     }
 
-    private static Command<CommandSourceStack> helpForChild( CommandNode<CommandSourceStack> node, String id, String command )
+    @Override
+    public LiteralArgumentBuilder<CommandSourceStack> executes( final Command<CommandSourceStack> command )
     {
-        return context -> {
-            context.getSource()
-                .sendSuccess( getHelp( context,
-                    node,
-                    id + "." + node.getName()
-                        .replace( '-', '_' ),
-                    command + " " + node.getName() ), false );
-            return 0;
-        };
-    }
-
-    private static Component getHelp( CommandContext<CommandSourceStack> context, CommandNode<CommandSourceStack> node, String id, String command )
-    {
-        // An ugly hack to extract usage information from the dispatcher. We generate a temporary node, generate
-        // the shorthand usage, and emit that.
-        CommandDispatcher<CommandSourceStack> dispatcher = context.getSource()
-            .getServer()
-            .getCommands()
-            .getDispatcher();
-        CommandNode<CommandSourceStack> temp = new LiteralCommandNode<>( "_", null, x -> true, null, null, false );
-        temp.addChild( node );
-        String usage = dispatcher.getSmartUsage( temp, context.getSource() )
-            .get( node )
-            .substring( node.getName()
-                .length() );
-
-        MutableComponent output = new TextComponent( "" ).append( coloured( "/" + command + usage, HEADER ) )
-            .append( " " )
-            .append( coloured( translate( "commands." + id + ".synopsis" ), SYNOPSIS ) )
-            .append( "\n" )
-            .append( translate( "commands." + id + ".desc" ) );
-
-        for( CommandNode<CommandSourceStack> child : node.getChildren() )
-        {
-            if( !child.getRequirement()
-                .test( context.getSource() ) || !(child instanceof LiteralCommandNode) )
-            {
-                continue;
-            }
-
-            output.append( "\n" );
-
-            MutableComponent component = coloured( child.getName(), NAME );
-            component.getStyle()
-                .withClickEvent( new ClickEvent( ClickEvent.Action.SUGGEST_COMMAND, "/" + command + " " + child.getName() ) );
-            output.append( component );
-
-            output.append( " - " )
-                .append( translate( "commands." + id + "." + child.getName() + ".synopsis" ) );
-        }
-
-        return output;
+        throw new IllegalStateException( "Cannot use executes on a HelpingArgumentBuilder" );
     }
 
     @Override
     public LiteralArgumentBuilder<CommandSourceStack> then( final ArgumentBuilder<CommandSourceStack, ?> argument )
     {
-        if( getRedirect() != null )
-        {
-            throw new IllegalStateException( "Cannot add children to a redirected node" );
-        }
+        if( getRedirect() != null ) throw new IllegalStateException( "Cannot add children to a redirected node" );
 
         if( argument instanceof HelpingArgumentBuilder )
         {
@@ -138,12 +81,6 @@ public final class HelpingArgumentBuilder extends LiteralArgumentBuilder<Command
         return super.then( argument );
     }
 
-    @Override
-    public LiteralArgumentBuilder<CommandSourceStack> executes( final Command<CommandSourceStack> command )
-    {
-        throw new IllegalStateException( "Cannot use executes on a HelpingArgumentBuilder" );
-    }
-
     @Override
     public LiteralCommandNode<CommandSourceStack> build()
     {
@@ -158,28 +95,24 @@ public final class HelpingArgumentBuilder extends LiteralArgumentBuilder<Command
     private LiteralCommandNode<CommandSourceStack> buildImpl( String id, String command )
     {
         HelpCommand helpCommand = new HelpCommand( id, command );
-        LiteralCommandNode<CommandSourceStack> node = new LiteralCommandNode<>( getLiteral(),
-            helpCommand, getRequirement(),
-            getRedirect(), getRedirectModifier(), isFork() );
+        LiteralCommandNode<CommandSourceStack> node = new LiteralCommandNode<>( getLiteral(), helpCommand, getRequirement(), getRedirect(), getRedirectModifier(), isFork() );
         helpCommand.node = node;
 
         // Set up a /... help command
-        LiteralArgumentBuilder<CommandSourceStack> helpNode =
-            LiteralArgumentBuilder.<CommandSourceStack>literal( "help" ).requires( x -> getArguments().stream()
-                    .anyMatch(
-                        y -> y.getRequirement()
-                            .test(
-                                x ) ) )
-                .executes( helpCommand );
+        LiteralArgumentBuilder<CommandSourceStack> helpNode = LiteralArgumentBuilder.<CommandSourceStack>literal( "help" )
+            .requires( x -> getArguments().stream().anyMatch( y -> y.getRequirement().test( x ) ) )
+            .executes( helpCommand );
 
         // Add all normal command children to this and the help node
         for( CommandNode<CommandSourceStack> child : getArguments() )
         {
             node.addChild( child );
 
-            helpNode.then( LiteralArgumentBuilder.<CommandSourceStack>literal( child.getName() ).requires( child.getRequirement() )
+            helpNode.then( LiteralArgumentBuilder.<CommandSourceStack>literal( child.getName() )
+                .requires( child.getRequirement() )
                 .executes( helpForChild( child, id, command ) )
-                .build() );
+                .build()
+            );
         }
 
         // And add alternative versions of which forward instead
@@ -187,10 +120,12 @@ public final class HelpingArgumentBuilder extends LiteralArgumentBuilder<Command
         {
             LiteralCommandNode<CommandSourceStack> child = childBuilder.build( id, command );
             node.addChild( child );
-            helpNode.then( LiteralArgumentBuilder.<CommandSourceStack>literal( child.getName() ).requires( child.getRequirement() )
+            helpNode.then( LiteralArgumentBuilder.<CommandSourceStack>literal( child.getName() )
+                .requires( child.getRequirement() )
                 .executes( helpForChild( child, id, command ) )
                 .redirect( child.getChild( "help" ) )
-                .build() );
+                .build()
+            );
         }
 
         node.addChild( helpNode.build() );
@@ -198,6 +133,10 @@ public final class HelpingArgumentBuilder extends LiteralArgumentBuilder<Command
         return node;
     }
 
+    private static final ChatFormatting HEADER = ChatFormatting.LIGHT_PURPLE;
+    private static final ChatFormatting SYNOPSIS = ChatFormatting.AQUA;
+    private static final ChatFormatting NAME = ChatFormatting.GREEN;
+
     private static final class HelpCommand implements Command<CommandSourceStack>
     {
         private final String id;
@@ -213,9 +152,54 @@ public final class HelpingArgumentBuilder extends LiteralArgumentBuilder<Command
         @Override
         public int run( CommandContext<CommandSourceStack> context )
         {
-            context.getSource()
-                .sendSuccess( getHelp( context, node, id, command ), false );
+            context.getSource().sendSuccess( getHelp( context, node, id, command ), false );
             return 0;
         }
     }
+
+    private static Command<CommandSourceStack> helpForChild( CommandNode<CommandSourceStack> node, String id, String command )
+    {
+        return context -> {
+            context.getSource().sendSuccess( getHelp( context, node, id + "." + node.getName().replace( '-', '_' ), command + " " + node.getName() ), false );
+            return 0;
+        };
+    }
+
+    private static Component getHelp( CommandContext<CommandSourceStack> context, CommandNode<CommandSourceStack> node, String id, String command )
+    {
+        // An ugly hack to extract usage information from the dispatcher. We generate a temporary node, generate
+        // the shorthand usage, and emit that.
+        CommandDispatcher<CommandSourceStack> dispatcher = context.getSource().getServer().getCommands().getDispatcher();
+        CommandNode<CommandSourceStack> temp = new LiteralCommandNode<>( "_", null, x -> true, null, null, false );
+        temp.addChild( node );
+        String usage = dispatcher.getSmartUsage( temp, context.getSource() ).get( node ).substring( node.getName().length() );
+
+        MutableComponent output = new TextComponent( "" )
+            .append( coloured( "/" + command + usage, HEADER ) )
+            .append( " " )
+            .append( coloured( translate( "commands." + id + ".synopsis" ), SYNOPSIS ) )
+            .append( "\n" )
+            .append( translate( "commands." + id + ".desc" ) );
+
+        for( CommandNode<CommandSourceStack> child : node.getChildren() )
+        {
+            if( !child.getRequirement().test( context.getSource() ) || !(child instanceof LiteralCommandNode) )
+            {
+                continue;
+            }
+
+            output.append( "\n" );
+
+            MutableComponent component = coloured( child.getName(), NAME );
+            component.getStyle().withClickEvent( new ClickEvent(
+                ClickEvent.Action.SUGGEST_COMMAND,
+                "/" + command + " " + child.getName()
+            ) );
+            output.append( component );
+
+            output.append( " - " ).append( translate( "commands." + id + "." + child.getName() + ".synopsis" ) );
+        }
+
+        return output;
+    }
 }

src/main/java/dan200/computercraft/shared/command/text/ChatHelpers.java

@@ -20,14 +20,12 @@ public final class ChatHelpers
 
     public static MutableComponent coloured( String text, ChatFormatting colour )
     {
-        MutableComponent component = new TextComponent( text == null ? "" : text );
-        component.setStyle( component.getStyle().withColor( colour ) );
-        return component;
+        return new TextComponent( text == null ? "" : text ).withStyle( colour );
     }
 
     public static <T extends MutableComponent> T coloured( T component, ChatFormatting colour )
     {
-        component.setStyle( component.getStyle().withColor( colour ) );
+        component.withStyle( colour );
         return component;
     }
 
@@ -46,10 +44,10 @@ public final class ChatHelpers
         return new TranslatableComponent( text == null ? "" : text, args );
     }
 
-    public static MutableComponent list( MutableComponent... children )
+    public static MutableComponent list( Component... children )
     {
         MutableComponent component = new TextComponent( "" );
-        for( MutableComponent child : children )
+        for( Component child : children )
         {
             component.append( child );
         }
@@ -69,12 +67,12 @@ public final class ChatHelpers
             : coloured( translate( "commands.computercraft.generic.no" ), ChatFormatting.RED );
     }
 
-    public static MutableComponent link( MutableComponent component, String command, MutableComponent toolTip )
+    public static Component link( MutableComponent component, String command, Component toolTip )
     {
         return link( component, new ClickEvent( ClickEvent.Action.RUN_COMMAND, command ), toolTip );
     }
 
-    public static MutableComponent link( MutableComponent component, ClickEvent click, MutableComponent toolTip )
+    public static Component link( Component component, ClickEvent click, Component toolTip )
     {
         Style style = component.getStyle();
 
@@ -82,9 +80,7 @@ public final class ChatHelpers
         style = style.withClickEvent( click );
         style = style.withHoverEvent( new HoverEvent( HoverEvent.Action.SHOW_TEXT, toolTip ) );
 
-        component.setStyle( style );
-
-        return component;
+        return component.copy().withStyle( style );
     }
 
     public static MutableComponent header( String text )
@@ -95,9 +91,9 @@ public final class ChatHelpers
     public static MutableComponent copy( String text )
     {
         TextComponent name = new TextComponent( text );
-        name.setStyle( name.getStyle()
+        Style style = name.getStyle()
             .withClickEvent( new ClickEvent( ClickEvent.Action.COPY_TO_CLIPBOARD, text ) )
-            .withHoverEvent( new HoverEvent( HoverEvent.Action.SHOW_TEXT, new TranslatableComponent( "gui.computercraft.tooltip.copy" ) ) ) );
-        return name;
+            .withHoverEvent( new HoverEvent( HoverEvent.Action.SHOW_TEXT, new TranslatableComponent( "gui.computercraft.tooltip.copy" ) ) );
+        return name.withStyle( style );
     }
 }

src/main/java/dan200/computercraft/shared/command/text/ServerTableFormatter.java

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.shared.command.text;
 
 import net.minecraft.commands.CommandSourceStack;
@@ -27,10 +26,7 @@ public class ServerTableFormatter implements TableFormatter
     public Component getPadding( Component component, int width )
     {
         int extraWidth = width - getWidth( component );
-        if( extraWidth <= 0 )
-        {
-            return null;
-        }
+        if( extraWidth <= 0 ) return null;
         return new TextComponent( StringUtils.repeat( ' ', extraWidth ) );
     }
 
@@ -43,8 +39,7 @@ public class ServerTableFormatter implements TableFormatter
     @Override
     public int getWidth( Component component )
     {
-        return component.getString()
-            .length();
+        return component.getString().length();
     }
 
     @Override

src/main/java/dan200/computercraft/shared/command/text/TableBuilder.java

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.shared.command.text;
 
 import dan200.computercraft.shared.command.CommandUtils;
@@ -21,17 +20,14 @@ import java.util.List;
 public class TableBuilder
 {
     private final int id;
+    private int columns = -1;
     private final Component[] headers;
     private final ArrayList<Component[]> rows = new ArrayList<>();
-    private int columns = -1;
     private int additional;
 
     public TableBuilder( int id, @Nonnull Component... headers )
     {
-        if( id < 0 )
-        {
-            throw new IllegalArgumentException( "ID must be positive" );
-        }
+        if( id < 0 ) throw new IllegalArgumentException( "ID must be positive" );
         this.id = id;
         this.headers = headers;
         columns = headers.length;
@@ -39,47 +35,33 @@ public class TableBuilder
 
     public TableBuilder( int id )
     {
-        if( id < 0 )
-        {
-            throw new IllegalArgumentException( "ID must be positive" );
-        }
+        if( id < 0 ) throw new IllegalArgumentException( "ID must be positive" );
         this.id = id;
         headers = null;
     }
 
     public TableBuilder( int id, @Nonnull String... headers )
     {
-        if( id < 0 )
-        {
-            throw new IllegalArgumentException( "ID must be positive" );
-        }
+        if( id < 0 ) throw new IllegalArgumentException( "ID must be positive" );
         this.id = id;
         this.headers = new Component[headers.length];
         columns = headers.length;
 
-        for( int i = 0; i < headers.length; i++ )
-        {
-            this.headers[i] = ChatHelpers.header( headers[i] );
-        }
+        for( int i = 0; i < headers.length; i++ ) this.headers[i] = ChatHelpers.header( headers[i] );
     }
 
     public void row( @Nonnull Component... row )
     {
-        if( columns == -1 )
-        {
-            columns = row.length;
-        }
-        if( row.length != columns )
-        {
-            throw new IllegalArgumentException( "Row is the incorrect length" );
-        }
+        if( columns == -1 ) columns = row.length;
+        if( row.length != columns ) throw new IllegalArgumentException( "Row is the incorrect length" );
         rows.add( row );
     }
 
     /**
      * Get the unique identifier for this table type.
      *
-     * When showing a table within Minecraft, previous instances of this table with the same ID will be removed from chat.
+     * When showing a table within Minecraft, previous instances of this table with
+     * the same ID will be removed from chat.
      *
      * @return This table's type.
      */
@@ -91,7 +73,8 @@ public class TableBuilder
     /**
      * Get the number of columns for this table.
      *
-     * This will be the same as {@link #getHeaders()}'s length if it is is non-{@code null}, otherwise the length of the first column.
+     * This will be the same as {@link #getHeaders()}'s length if it is is non-{@code null},
+     * otherwise the length of the first column.
      *
      * @return The number of columns.
      */
@@ -122,6 +105,20 @@ public class TableBuilder
         this.additional = additional;
     }
 
+    /**
+     * Trim this table to a given height.
+     *
+     * @param height The desired height.
+     */
+    public void trim( int height )
+    {
+        if( rows.size() > height )
+        {
+            additional += rows.size() - height - 1;
+            rows.subList( height - 1, rows.size() ).clear();
+        }
+    }
+
     public void display( CommandSourceStack source )
     {
         if( CommandUtils.isPlayer( source ) )
@@ -135,19 +132,4 @@ public class TableBuilder
             new ServerTableFormatter( source ).display( this );
         }
     }
-
-    /**
-     * Trim this table to a given height.
-     *
-     * @param height The desired height.
-     */
-    public void trim( int height )
-    {
-        if( rows.size() > height )
-        {
-            additional += rows.size() - height - 1;
-            rows.subList( height - 1, rows.size() )
-                .clear();
-        }
-    }
 }

src/main/java/dan200/computercraft/shared/command/text/TableFormatter.java

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.shared.command.text;
 
 import net.minecraft.ChatFormatting;
@@ -21,12 +20,30 @@ public interface TableFormatter
     Component SEPARATOR = coloured( "| ", ChatFormatting.GRAY );
     Component HEADER = coloured( "=", ChatFormatting.GRAY );
 
+    /**
+     * Get additional padding for the component.
+     *
+     * @param component The component to pad
+     * @param width     The desired width for the component
+     * @return The padding for this component, or {@code null} if none is needed.
+     */
+    @Nullable
+    Component getPadding( Component component, int width );
+
+    /**
+     * Get the minimum padding between each column.
+     *
+     * @return The minimum padding.
+     */
+    int getColumnPadding();
+
+    int getWidth( Component component );
+
+    void writeLine( int id, Component component );
+
     default int display( TableBuilder table )
     {
-        if( table.getColumns() <= 0 )
-        {
-            return 0;
-        }
+        if( table.getColumns() <= 0 ) return 0;
 
         int rowId = table.getId();
         int columns = table.getColumns();
@@ -35,10 +52,7 @@ public interface TableFormatter
         Component[] headers = table.getHeaders();
         if( headers != null )
         {
-            for( int i = 0; i < columns; i++ )
-            {
-                maxWidths[i] = getWidth( headers[i] );
-            }
+            for( int i = 0; i < columns; i++ ) maxWidths[i] = getWidth( headers[i] );
         }
 
         for( Component[] row : table.getRows() )
@@ -46,28 +60,19 @@ public interface TableFormatter
             for( int i = 0; i < row.length; i++ )
             {
                 int width = getWidth( row[i] );
-                if( width > maxWidths[i] )
-                {
-                    maxWidths[i] = width;
-                }
+                if( width > maxWidths[i] ) maxWidths[i] = width;
             }
         }
 
         // Add a small amount of padding after each column
         {
             int padding = getColumnPadding();
-            for( int i = 0; i < maxWidths.length - 1; i++ )
-            {
-                maxWidths[i] += padding;
-            }
+            for( int i = 0; i < maxWidths.length - 1; i++ ) maxWidths[i] += padding;
         }
 
         // And compute the total width
         int totalWidth = (columns - 1) * getWidth( SEPARATOR );
-        for( int x : maxWidths )
-        {
-            totalWidth += x;
-        }
+        for( int x : maxWidths ) totalWidth += x;
 
         if( headers != null )
         {
@@ -76,10 +81,7 @@ public interface TableFormatter
             {
                 line.append( headers[i] );
                 Component padding = getPadding( headers[i], maxWidths[i] );
-                if( padding != null )
-                {
-                    line.append( padding );
-                }
+                if( padding != null ) line.append( padding );
                 line.append( SEPARATOR );
             }
             line.append( headers[columns - 1] );
@@ -100,10 +102,7 @@ public interface TableFormatter
             {
                 line.append( row[i] );
                 Component padding = getPadding( row[i], maxWidths[i] );
-                if( padding != null )
-                {
-                    line.append( padding );
-                }
+                if( padding != null ) line.append( padding );
                 line.append( SEPARATOR );
             }
             line.append( row[columns - 1] );
@@ -117,25 +116,4 @@ public interface TableFormatter
 
         return rowId - table.getId();
     }
-
-    int getWidth( Component component );
-
-    /**
-     * Get the minimum padding between each column.
-     *
-     * @return The minimum padding.
-     */
-    int getColumnPadding();
-
-    /**
-     * Get additional padding for the component.
-     *
-     * @param component The component to pad
-     * @param width     The desired width for the component
-     * @return The padding for this component, or {@code null} if none is needed.
-     */
-    @Nullable
-    Component getPadding( Component component, int width );
-
-    void writeLine( int id, Component component );
 }

src/main/java/dan200/computercraft/shared/common/BlockGeneric.java

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.shared.common;
 
 import net.minecraft.core.BlockPos;
@@ -23,66 +22,45 @@ import net.minecraft.world.phys.BlockHitResult;
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 import java.util.Random;
+import java.util.function.Supplier;
 
 public abstract class BlockGeneric extends BaseEntityBlock
 {
-    private final BlockEntityType<? extends TileGeneric> type;
+    private final Supplier<? extends BlockEntityType<? extends TileGeneric>> type;
 
-    public BlockGeneric( Properties settings, BlockEntityType<? extends TileGeneric> type )
+    public BlockGeneric( Properties settings, Supplier<? extends BlockEntityType<? extends TileGeneric>> type )
     {
         super( settings );
         this.type = type;
     }
 
-    public BlockEntityType<? extends TileGeneric> getType()
-    {
-        return type;
-    }
-
-    @Override
-    public RenderShape getRenderShape( BlockState state )
-    {
-        return RenderShape.MODEL;
-    }
-
-    @Override
-    @Deprecated
-    public final void neighborChanged( @Nonnull BlockState state, Level world, @Nonnull BlockPos pos, @Nonnull Block neighbourBlock,
-                                       @Nonnull BlockPos neighbourPos, boolean isMoving )
-    {
-        BlockEntity tile = world.getBlockEntity( pos );
-        if( tile instanceof TileGeneric )
-        {
-            ((TileGeneric) tile).onNeighbourChange( neighbourPos );
-        }
-    }
-
     @Override
     @Deprecated
     public final void onRemove( @Nonnull BlockState block, @Nonnull Level world, @Nonnull BlockPos pos, BlockState replace, boolean bool )
     {
-        if( block.getBlock() == replace.getBlock() )
-        {
-            return;
-        }
+        if( block.getBlock() == replace.getBlock() ) return;
 
         BlockEntity tile = world.getBlockEntity( pos );
         super.onRemove( block, world, pos, replace, bool );
         world.removeBlockEntity( pos );
-        if( tile instanceof TileGeneric )
-        {
-            ((TileGeneric) tile).destroy();
-        }
+        if( tile instanceof TileGeneric generic ) generic.destroy();
     }
 
     @Nonnull
     @Override
     @Deprecated
-    public final InteractionResult use( @Nonnull BlockState state, Level world, @Nonnull BlockPos pos, @Nonnull Player player, @Nonnull InteractionHand hand,
-                                        @Nonnull BlockHitResult hit )
+    public final InteractionResult use( @Nonnull BlockState state, Level world, @Nonnull BlockPos pos, @Nonnull Player player, @Nonnull InteractionHand hand, @Nonnull BlockHitResult hit )
     {
         BlockEntity tile = world.getBlockEntity( pos );
-        return tile instanceof TileGeneric ? ((TileGeneric) tile).onActivate( player, hand, hit ) : InteractionResult.PASS;
+        return tile instanceof TileGeneric generic ? generic.onActivate( player, hand, hit ) : InteractionResult.PASS;
+    }
+
+    @Override
+    @Deprecated
+    public final void neighborChanged( @Nonnull BlockState state, Level world, @Nonnull BlockPos pos, @Nonnull Block neighbourBlock, @Nonnull BlockPos neighbourPos, boolean isMoving )
+    {
+        BlockEntity tile = world.getBlockEntity( pos );
+        if( tile instanceof TileGeneric generic ) generic.onNeighbourChange( neighbourPos );
     }
 
     @Override
@@ -90,20 +68,21 @@ public abstract class BlockGeneric extends BaseEntityBlock
     public void tick( @Nonnull BlockState state, ServerLevel world, @Nonnull BlockPos pos, @Nonnull Random rand )
     {
         BlockEntity te = world.getBlockEntity( pos );
-        if( te instanceof TileGeneric )
-        {
-            ((TileGeneric) te).blockTick();
-        }
+        if( te instanceof TileGeneric generic ) generic.blockTick();
     }
 
     @Nullable
     @Override
-    public BlockEntity newBlockEntity( BlockPos pos, BlockState state )
+    public BlockEntity newBlockEntity( @Nonnull BlockPos pos, @Nonnull BlockState state )
     {
-        if( this.type != null )
-        {
-            return type.create( pos, state );
-        }
-        return null;
+        return type.get().create( pos, state );
+    }
+
+    @Nonnull
+    @Override
+    @Deprecated
+    public RenderShape getRenderShape( @Nonnull BlockState state )
+    {
+        return RenderShape.MODEL;
     }
 }

src/main/java/dan200/computercraft/shared/common/ClientTerminal.java

@@ -3,12 +3,10 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.shared.common;
 
 import dan200.computercraft.core.terminal.Terminal;
 import dan200.computercraft.shared.network.client.TerminalState;
-import net.minecraft.nbt.CompoundTag;
 
 public class ClientTerminal implements ITerminal
 {
@@ -79,19 +77,4 @@ public class ClientTerminal implements ITerminal
             terminalChanged = true;
         }
     }
-
-    public void readDescription( CompoundTag nbt )
-    {
-        colour = nbt.getBoolean( "colour" );
-        if( nbt.contains( "terminal" ) )
-        {
-            CompoundTag terminal = nbt.getCompound( "terminal" );
-            resizeTerminal( terminal.getInt( "term_width" ), terminal.getInt( "term_height" ) );
-            this.terminal.readFromNBT( terminal );
-        }
-        else
-        {
-            deleteTerminal();
-        }
-    }
 }

src/main/java/dan200/computercraft/shared/common/ColourableRecipe.java

@@ -3,7 +3,6 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.shared.common;
 
 import dan200.computercraft.shared.util.ColourTracker;
@@ -21,8 +20,6 @@ import javax.annotation.Nonnull;
 
 public final class ColourableRecipe extends CustomRecipe
 {
-    public static final RecipeSerializer<?> SERIALIZER = new SimpleRecipeSerializer<>( ColourableRecipe::new );
-
     private ColourableRecipe( ResourceLocation id )
     {
         super( id );
@@ -36,17 +33,11 @@ public final class ColourableRecipe extends CustomRecipe
         for( int i = 0; i < inv.getContainerSize(); i++ )
         {
             ItemStack stack = inv.getItem( i );
-            if( stack.isEmpty() )
-            {
-                continue;
-            }
+            if( stack.isEmpty() ) continue;
 
             if( stack.getItem() instanceof IColouredItem )
             {
-                if( hasColourable )
-                {
-                    return false;
-                }
+                if( hasColourable ) return false;
                 hasColourable = true;
             }
             else if( ColourUtils.getStackColour( stack ) != null )
@@ -74,9 +65,11 @@ public final class ColourableRecipe extends CustomRecipe
         {
             ItemStack stack = inv.getItem( i );
 
-            if( stack.isEmpty() )
+            if( stack.isEmpty() ) continue;
+
+            if( stack.getItem() instanceof IColouredItem )
             {
-                continue;
+                colourable = stack;
             }
             else
             {
@@ -104,4 +97,6 @@ public final class ColourableRecipe extends CustomRecipe
     {
         return SERIALIZER;
     }
+
+    public static final SimpleRecipeSerializer<?> SERIALIZER = new SimpleRecipeSerializer<>( ColourableRecipe::new );
 }

src/main/java/dan200/computercraft/shared/common/ContainerHeldItem.java

@@ -3,10 +3,9 @@
  * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
  */
-
 package dan200.computercraft.shared.common;
 
-import dan200.computercraft.shared.ComputerCraftRegistry;
+import dan200.computercraft.shared.Registry;
 import dan200.computercraft.shared.network.container.HeldItemContainerData;
 import net.fabricmc.fabric.api.screenhandler.v1.ExtendedScreenHandlerFactory;
 import net.minecraft.network.FriendlyByteBuf;
@@ -32,13 +31,12 @@ public class ContainerHeldItem extends AbstractContainerMenu
         super( type, id );
 
         this.hand = hand;
-        stack = player.getItemInHand( hand )
-            .copy();
+        stack = player.getItemInHand( hand ).copy();
     }
 
     public static ContainerHeldItem createPrintout( int id, Inventory inventory, HeldItemContainerData data )
     {
-        return new ContainerHeldItem( ComputerCraftRegistry.ModContainers.PRINTOUT, id, inventory.player, data.getHand() );
+        return new ContainerHeldItem( Registry.ModContainers.PRINTOUT, id, inventory.player, data.getHand() );
     }
 
     @Nonnull
@@ -50,10 +48,7 @@ public class ContainerHeldItem extends AbstractContainerMenu
     @Override
     public boolean stillValid( @Nonnull Player player )
     {
-        if( !player.isAlive() )
-        {
-            return false;
-        }
+        if( !player.isAlive() ) return false;
 
         ItemStack stack = player.getItemInHand( hand );
         return stack == this.stack || !stack.isEmpty() && !this.stack.isEmpty() && stack.getItem() == this.stack.getItem();