Merge branch 'mc-1.15.x' into mc-1.16.x

Fix TBO normalisation issues on old GPUs

.github/ISSUE_TEMPLATE/bug_report.md

@@ -12,4 +12,5 @@ labels: bug
 ## Useful information to include:
  - Minecraft version
  - CC: Tweaked version
+ - Logs: These will be located in the `logs/` directory of your Minecraft instance. Please upload them as a gist or directly into this editor.
  - Detailed reproduction steps: sometimes I can spot a bug pretty easily, but often it's much more obscure. The more information I have to help reproduce it, the quicker it'll get fixed.

.github/workflows/main-ci.yml

@@ -10,10 +10,10 @@ jobs:
     steps:
     - uses: actions/checkout@v2
 
-    - name: Set up JDK 1.8
+    - name: Set up Java 8
       uses: actions/setup-java@v1
       with:
-        java-version: 1.8
+        java-version: 8
 
     - name: Cache gradle dependencies
       uses: actions/cache@v1
@@ -32,12 +32,11 @@ jobs:
         name: CC-Tweaked
         path: build/libs
 
-  lint-lua:
-    name: Lint Lua
-    runs-on: ubuntu-latest
+    - name: Upload Coverage
+      run: bash <(curl -s https://codecov.io/bash)
 
-    steps:
-    - uses: actions/checkout@v1
+    - name: Generate Java documentation stubs
+      run: ./gradlew luaJavadoc --no-daemon
 
     - name: Lint Lua code
       run: |

.github/workflows/make-doc.yml

@@ -2,7 +2,9 @@ name: Build documentation
 
 on:
   push:
-    branches: [ master ]
+    branches:
+    - master
+    - mc-1.15.x
     tags:
   release:
     types: [ published ]
@@ -15,6 +17,25 @@ jobs:
     steps:
     - uses: actions/checkout@v1
 
+    - name: Set up Java 8
+      uses: actions/setup-java@v1
+      with:
+        java-version: 8
+
+    - name: Cache gradle dependencies
+      uses: actions/cache@v1
+      with:
+        path: ~/.gradle/caches
+        key: ${{ runner.os }}-gradle-${{ hashFiles('gradle.properties') }}
+        restore-keys: |
+          ${{ runner.os }}-gradle-
+
+    - name: Build with Gradle
+      run: ./gradlew compileJava --no-daemon || ./gradlew compileJava --no-daemon
+
+    - name: Generate Java documentation stubs
+      run: ./gradlew luaJavadoc --no-daemon
+
     - name: Build documentation
       run: |
         test -d bin || mkdir bin

.gitignore

@@ -4,6 +4,7 @@
 /build
 /out
 /doc/**/*.html
+/doc/javadoc/
 /doc/index.json
 
 # Runtime directories

CONTRIBUTING.md

@@ -10,7 +10,7 @@ do use the issue templates - they provide a useful hint on what information to p
 
 ## Developing
 In order to develop CC: Tweaked, you'll need to download the source code and then run it. This is a pretty simple
-process.
+process. When building on Windows, Use `gradlew.bat` instead of `./gradlew`.
 
  - **Clone the repository:** `git clone https://github.com/SquidDev-CC/CC-Tweaked.git && cd CC-Tweaked`
  - **Setup Forge:** `./gradlew build`
@@ -29,8 +29,13 @@ are run whenever you submit a PR, it's often useful to run this before committin
  - **[illuaminate]:** Checks Lua code for semantic and styleistic issues. See [the usage section][illuaminate-usage] for
    how to download and run it.
 
+## Translations
+Translations are managed through [Weblate], an online interface for managing language strings. This is synced
+automatically with GitHub, so please don't submit PRs adding/changing translations!
+
 [new-issue]: https://github.com/SquidDev-CC/CC-Tweaked/issues/new/choose "Create a new issue"
 [community]: README.md#Community "Get in touch with the community."
 [checkstyle]: https://checkstyle.org/
 [illuaminate]: https://github.com/SquidDev/illuaminate/
 [illuaminate-usage]: https://github.com/SquidDev/illuaminate/blob/master/README.md#usage
+[weblate]: https://i18n.tweaked.cc/projects/cc-tweaked/minecraft/

README.md

@@ -1,4 +1,4 @@
-# ![CC: Tweaked](logo.png)
+# ![CC: Tweaked](doc/logo.png)
 [![Current build status](https://github.com/SquidDev-CC/CC-Tweaked/workflows/Build/badge.svg)](https://github.com/SquidDev-CC/CC-Tweaked/actions "Current build status") [![Download CC: Tweaked on CurseForge](http://cf.way2muchnoise.eu/title/cc-tweaked.svg)](https://minecraft.curseforge.com/projects/cc-tweaked "Download CC: Tweaked on CurseForge")
 
 CC: Tweaked is a fork of [ComputerCraft](https://github.com/dan200/ComputerCraft), adding programmable computers,
@@ -50,12 +50,12 @@ I'd generally recommend you don't contact me directly (email, DM, etc...) unless
 report exploits). You'll get a far quicker response if you ask the whole community!
 
 ## Using
-If you want to depend on CC: Tweaked, we have a maven repo. However, you should be wary that some functionality is only
-exposed by CC:T's API and not vanilla ComputerCraft. If you wish to support all variations of ComputerCraft, I recommend
-using [cc.crzd.me's maven](https://cc.crzd.me/maven/) instead.
+CC: Tweaked is hosted on my maven repo, and so is relatively simple to depend on. You may wish to add a soft (or hard)
+dependency in your `mods.toml` file, with the appropriate version bounds, to ensure that API functionality you depend
+on is present.
 
 ```groovy
-dependencies {
+repositories {
   maven { url 'https://squiddev.cc/maven/' }
 }
 

build.gradle

@@ -9,7 +9,7 @@ buildscript {
     }
     dependencies {
         classpath 'com.google.code.gson:gson:2.8.1'
-        classpath 'net.minecraftforge.gradle:ForgeGradle:3.0.154'
+        classpath 'net.minecraftforge.gradle:ForgeGradle:3.0.181'
         classpath 'net.sf.proguard:proguard-gradle:6.1.0beta2'
         classpath 'org.ajoberstar.grgit:grgit-gradle:3.0.0'
     }
@@ -17,6 +17,7 @@ buildscript {
 
 plugins {
     id "checkstyle"
+    id "jacoco"
     id "com.github.hierynomus.license" version "0.15.0"
     id "com.matthewprenger.cursegradle" version "1.3.0"
     id "com.github.breadmoirai.github-release" version "2.2.4"
@@ -32,6 +33,8 @@ version = mod_version
 group = "org.squiddev"
 archivesBaseName = "cc-tweaked-${mc_version}"
 
+sourceCompatibility = targetCompatibility = compileJava.sourceCompatibility = compileJava.targetCompatibility = '1.8'
+
 minecraft {
     runs {
         client {
@@ -47,8 +50,8 @@ minecraft {
         }
 
         server {
-            workingDirectory project.file('run')
-            property 'forge.logging.markers', 'SCAN,REGISTRIES,REGISTRYDUMP'
+            workingDirectory project.file("run/server-${mc_version}")
+            property 'forge.logging.markers', 'REGISTRIES,REGISTRYDUMP'
             property 'forge.logging.console.level', 'debug'
 
             mods {
@@ -60,7 +63,7 @@ minecraft {
 
         data {
             workingDirectory project.file('run')
-            property 'forge.logging.markers', 'SCAN,REGISTRIES,REGISTRYDUMP'
+            property 'forge.logging.markers', 'REGISTRIES,REGISTRYDUMP'
             property 'forge.logging.console.level', 'debug'
 
             args '--mod', 'computercraft', '--all', '--output', file('src/generated/resources/'), '--existing', file('src/main/resources/')
@@ -77,11 +80,14 @@ minecraft {
     accessTransformer file('src/main/resources/META-INF/accesstransformer.cfg')
 }
 
-sourceSets.main.resources {
-    srcDir 'src/generated/resources'
+sourceSets {
+    main.resources {
+        srcDir 'src/generated/resources'
+    }
 }
 
 repositories {
+    mavenCentral()
     maven {
         name "SquidDev"
         url "https://squiddev.cc/maven"
@@ -92,6 +98,7 @@ configurations {
     shade
     compile.extendsFrom shade
     deployerJars
+    cctJavadoc
 }
 
 dependencies {
@@ -99,17 +106,23 @@ dependencies {
 
     minecraft "net.minecraftforge:forge:${mc_version}-${forge_version}"
 
-    compileOnly fg.deobf("mezz.jei:jei-1.14.4:6.0.0.27:api")
-    compileOnly fg.deobf("com.blamejared.crafttweaker:CraftTweaker-1.14.4:5.0.1.162")
+    compileOnly fg.deobf("mezz.jei:jei-1.16.3:7.6.0.49:api")
+    compileOnly fg.deobf("com.blamejared.crafttweaker:CraftTweaker-1.16.3:7.0.0.48")
 
-    runtimeOnly fg.deobf("mezz.jei:jei-1.14.4:6.0.0.27")
+    runtimeOnly fg.deobf("mezz.jei:jei-1.16.3:7.6.0.49")
+
+    compileOnly 'com.google.auto.service:auto-service:1.0-rc7'
+    annotationProcessor 'com.google.auto.service:auto-service:1.0-rc7'
 
     shade 'org.squiddev:Cobalt:0.5.1-SNAPSHOT'
 
     testImplementation 'org.junit.jupiter:junit-jupiter-api:5.4.2'
     testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.4.2'
+    testImplementation 'org.hamcrest:hamcrest:2.2'
 
     deployerJars "org.apache.maven.wagon:wagon-ssh:3.0.0"
+
+    cctJavadoc 'cc.tweaked:cct-javadoc:1.1.0'
 }
 
 // Compile tasks
@@ -118,6 +131,24 @@ javadoc {
     include "dan200/computercraft/api/**/*.java"
 }
 
+task luaJavadoc(type: Javadoc) {
+    description "Generates documentation for Java-side Lua functions."
+    group "documentation"
+
+    source = sourceSets.main.allJava
+    destinationDir = file("doc/javadoc")
+    classpath = sourceSets.main.compileClasspath
+
+    options.docletpath = configurations.cctJavadoc.files as List
+    options.doclet = "cc.tweaked.javadoc.LuaDoclet"
+
+    // Attempt to run under Java 11 (any Java >= 9 will work though).
+    if(System.getProperty("java.version").startsWith("1.")
+        && (System.getenv("JAVA_HOME_11_X64") != null || project.hasProperty("java11Home"))) {
+        executable = "${System.getenv("JAVA_HOME_11_X64") ?: project.property("java11Home")}/bin/javadoc"
+    }
+}
+
 jar {
     dependsOn javadoc
 
@@ -144,8 +175,6 @@ jar {
     }
 }
 
-
-
 import java.nio.charset.StandardCharsets
 import java.nio.file.*
 import java.util.zip.*
@@ -200,8 +229,6 @@ task proguardMove(dependsOn: proguard) {
     }
 }
 
-
-
 processResources {
     inputs.property "version", mod_version
     inputs.property "mcversion", mc_version
@@ -288,6 +315,15 @@ test {
     }
 }
 
+jacocoTestReport {
+    reports {
+        xml.enabled true
+        html.enabled true
+    }
+}
+
+check.dependsOn jacocoTestReport
+
 license {
     mapping("java", "SLASHSTAR_STYLE")
     strictCheck true

config/checkstyle/checkstyle.xml

@@ -10,6 +10,10 @@
         <property name="file" value="config/checkstyle/suppressions.xml" />
     </module>
 
+    <module name="BeforeExecutionExclusionFileFilter">
+        <property name="fileNamePattern" value="render_old"/>
+    </module>
+
     <module name="TreeWalker">
         <!-- Annotations -->
         <module name="AnnotationLocation" />
@@ -110,11 +114,11 @@
         </module>
         <module name="ParameterName" />
         <module name="StaticVariableName">
-            <property name="format" value="^[a-z][a-zA-Z0-9]*|CAPABILITY(_[A-Z]+)?$" />
+            <property name="format" value="^[a-z][a-zA-Z0-9]*|CAPABILITY(_[A-Z_]+)?$" />
             <property name="applyToPrivate" value="false" />
         </module>
         <module name="StaticVariableName">
-            <property name="format" value="^(s_)?[a-z][a-zA-Z0-9]*|CAPABILITY(_[A-Z]+)?$" />
+            <property name="format" value="^(s_)?[a-z][a-zA-Z0-9]*|CAPABILITY(_[A-Z_]+)?$" />
             <property name="applyToPrivate" value="true" />
         </module>
         <module name="TypeName" />

config/checkstyle/suppressions.xml

@@ -9,4 +9,7 @@
 
     <!-- Do not check for missing package Javadoc. -->
     <suppress checks="JavadocStyle" files=".*[\\/]package-info.java" />
+
+    <!-- The commands API is documented in Lua. -->
+    <suppress checks="SummaryJavadocCheck" files=".*[\\/]CommandAPI.java" />
 </suppressions>

doc/stub/commands.lua

@@ -1,6 +0,0 @@
-function exec(command) end
-function execAsync(commad) end
-function list() end
-function getBlockPosition() end
-function getBlockInfos(min_x, min_y, min_z, max_x, max_y, max_z) end
-function getBlockInfo(x, y, z) end

doc/stub/fs.lua

@@ -2,41 +2,33 @@
 --
 -- @module fs
 
-function list(path) end
-function combine(base, child) end
-function getName(path) end
-function getSize(path) end
-function exists(path) end
-function isDir(path) end
-function isReadOnly(path) end
-function makeDir(path) end
-function move(from, to) end
-function copy(from, to) end
-function delete(path) end
-function open(path, mode) end
-function getDrive(path) end
-function getFreeSpace(path) end
-function find(pattern) end
-function getDir(path) end
-
---- A file handle which can be read from.
+--- Returns true if a path is mounted to the parent filesystem.
 --
--- @type ReadHandle
--- @see fs.open
-local ReadHandle = {}
-function ReadHandle.read(count) end
-function ReadHandle.readAll() end
-function ReadHandle.readLine(with_trailing) end
-function ReadHandle.seek(whence, offset) end
-function ReadHandle.close() end
-
---- A file handle which can be written to.
+-- The root filesystem "/" is considered a mount, along with disk folders and
+-- the rom folder. Other programs (such as network shares) can exstend this to
+-- make other mount types by correctly assigning their return value for getDrive.
 --
--- @type WriteHandle
--- @see fs.open
-local WriteHandle = {}
-function WriteHandle.write(text) end
-function WriteHandle.writeLine(text) end
-function WriteHandle.flush(text) end
-function WriteHandle.seek(whence, offset) end
-function WriteHandle.close() end
+-- @tparam string path The path to check.
+-- @treturn boolean If the path is mounted, rather than a normal file/folder.
+-- @throws If the path does not exist.
+-- @see getDrive
+function isDriveRoot(path) end
+
+--[[- Provides completion for a file or directory name, suitable for use with
+@{read}.
+
+When a directory is a possible candidate for completion, two entries are
+included - one with a trailing slash (indicating that entries within this
+directory exist) and one without it (meaning this entry is an immediate
+completion candidate). `include_dirs` can be set to @{false} to only include
+those with a trailing slash.
+
+@tparam string path The path to complete.
+@tparam string location The location where paths are resolved from.
+@tparam[opt] boolean include_files When @{false}, only directories will be
+included in the returned list.
+@tparam[opt] boolean include_dirs When @{false}, "raw" directories will not be
+included in the returned list.
+@treturn { string... } A list of possible completion candidates.
+]]
+function complete(path, location, include_files, include_dirs) end

doc/stub/global.lua

@@ -0,0 +1,55 @@
+--[[-
+Global functions defined by `bios.lua`. This does not include standard Lua
+functions.
+
+@module _G
+]]
+
+--[[- Pauses execution for the specified number of seconds.
+
+As it waits for a fixed amount of world ticks, `time` will automatically be
+rounded up to the nearest multiple of 0.05 seconds. If you are using coroutines
+or the @{parallel|parallel API}, it will only pause execution of the current
+thread, not the whole program.
+
+**Note** Because sleep internally uses timers, it is a function that yields.
+This means that you can use it to prevent "Too long without yielding" errors,
+however, as the minimum sleep time is 0.05 seconds, it will slow your program
+down.
+
+**Warning** Internally, this function queues and waits for a timer event (using
+@{os.startTimer}), however it does not listen for any other events. This means
+that any event that occurs while sleeping will be entirely discarded. If you
+need to receive events while sleeping, consider using @{os.startTimer|timers},
+or the @{parallel|parallel API}.
+
+@tparam number time The number of seconds to sleep for, rounded up to the
+nearest multiple of 0.05.
+
+@see os.startTimer
+]]
+function sleep(time) end
+
+function write(text) end
+function print(...) end
+function printError(...) end
+
+function read(replaceChar, history, completeFn, default) end
+
+--- The ComputerCraft and Minecraft version of the current computer environment.
+--
+-- For example, `ComputerCraft 1.93.0 (Minecraft 1.15.2)`.
+_HOST = _HOST
+
+--[[- The default computer settings as defined in the ComputerCraft
+configuration.
+
+This is a comma-separated list of settings pairs defined by the mod
+configuration or server owner. By default, it is empty.
+
+An example value to disable autocompletion:
+
+    shell.autocomplete=false,lua.autocomplete=false,edit.autocomplete=false
+
+]]
+_CC_DEFAULT_SETTINGS = _CC_DEFAULT_SETTINGS

doc/stub/http.lua

@@ -93,47 +93,6 @@ function get(...) end
 -- @treturn Response|nil The failing http response, if available.
 function post(...) end
 
---- A http response. This acts very much like a @{fs.ReadHandle|file}, though
--- provides some http specific methods.
---
--- #### `http_success` event
--- #### `http_failure` event
---
--- @type Response
--- @see http.request On how to make a http request.
-local Response = {}
-
---- Returns the response code and response message returned by the server
---
--- @treturn number The response code (i.e. 200)
--- @treturn string The response message (i.e. "OK")
-function Response.getResponseCode() end
-
---- Get a table containing the response's headers, in a format similar to that
--- required by @{http.request}. If multiple headers are sent with the same
--- name, they will be combined with a comma.
---
--- @treturn { [string]=string } The response's headers.
--- Make a request to [example.computercraft.cc](https://example.computercraft.cc),
--- and print the returned headers.
--- ```lua
--- local request = http.get("https://example.computercraft.cc")
--- print(textutils.serialize(request.getResponseHeaders()))
--- -- => {
--- --   [ "Content-Type" ] = "text/plain; charset=utf8",
--- --   [ "content-length" ] = 17,
--- --   ...
--- -- }
--- request.close()
--- ```
-function Response.getResponseHeaders() end
-
-function Response.read(count) end
-function Response.readAll() end
-function Response.readLine(with_trailing) end
-function Response.seek(whence, offset) end
-function Response.close() end
-
 --- Asynchronously determine whether a URL can be requested.
 --
 -- If this returns `true`, one should also listen for [`http_check`
@@ -198,32 +157,3 @@ function websocket(url, headers) end
 -- @tparam[opt] { [string] = string } headers Additional headers to send as part
 -- of the initial websocket connection.
 function websocketAsync(url, headers) end
-
---- A websocket, which can be used to send an receive messages with a web
--- server.
---
--- @type Websocket
--- @see http.websocket On how to open a websocket.
-local Websocket = {}
-
---- Send a websocket message to the connected server.
---
--- @tparam string message The message to send.
--- @tparam[opt] boolean binary Whether this message should be treated as a
--- binary string, rather than encoded text.
--- @throws If the websocket has been closed.
-function Websocket.send(message, binary) end
-
---- Wait for a message from the server.
---
--- @tparam[opt] number timeout The number of seconds to wait if no message is
--- received.
--- @treturn[1] string The received message.
--- @treturn boolean If this was a binary message.
--- @treturn[2] nil If the websocket was closed while waiting, or if we timed out.
--- @throws If the websocket has been closed.
-function Websocket.receive(timeout) end
-
---- Close this websocket. This will terminate the connection, meaning messages
--- can no longer be sent or received along it.
-function Websocket.close() end

doc/stub/os.lua

@@ -1,17 +1,121 @@
-function queueEvent(event, ...) end
-function startTimer(delay) end
-function setAlarm(time) end
-function shutdown() end
-function reboot() end
-function getComputerID() end
-computerID = getComputerID
-function setComputerLabel(label) end
-function getComputerLabel() end
-computerLabel = getComputerLabel
-function clock() end
-function time(timezone) end
-function day(timezone) end
-function cancelTimer(id) end
-function cancelAlarm(id) end
-function epoch(timezone) end
-function date(format, time) end
+-- Defined in bios.lua
+
+--[[- Loads the given API into the global environment.
+
+**Warning** This function is deprecated. Use of this function will pollute the
+global table, use @{require} instead.
+
+This function loads and executes the file at the given path, and all global
+variables and functions exported by it will by available through the use of
+`myAPI.<function name>`, where `myAPI` is the base name of the API file.
+
+@tparam string path The path of the API to load.
+@treturn boolean Whether or not the API was successfully loaded.
+
+@deprecated Use @{require}.
+]]
+function loadAPI(path) end
+
+--- Unloads an API which was loaded by @{os.loadAPI}.
+--
+-- This effectively removes the specified table from `_G`.
+--
+-- @tparam string name The name of the API to unload.
+-- @deprecated Use @{require}.
+function unloadAPI(name) end
+
+--[[- Pause execution of the current thread and waits for any events matching
+`filter`.
+
+This function @{coroutine.yield|yields} the current process and waits for it
+to be resumed with a vararg list where the first element matches `filter`.
+If no `filter` is supplied, this will match all events.
+
+Unlike @{os.pullEventRaw}, it will stop the application upon a "terminate"
+event, printing the error "Terminated".
+
+@tparam[opt] string filter Event to filter for.
+@treturn string event The name of the event that fired.
+@treturn any param... Optional additional parameters of the event.
+@usage Listen for `mouse_click` events.
+
+    while true do
+        local event, button, x, y = os.pullEvent("mouse_click")
+        print("Button", button, "was clicked at", x, ",", y)
+    end
+
+@usage Listen for multiple events.
+
+    while true do
+        local eventData = {os.pullEvent()}
+        local event = eventData[1]
+
+        if event == "mouse_click" then
+            print("Button", eventData[2], "was clicked at", eventData[3], ",", eventData[4])
+        elseif event == "key" then
+            print("Key code", eventData[2], "was pressed")
+        end
+    end
+
+@see os.pullEventRaw To pull the terminate event.
+]]
+function pullEvent(filter) end
+
+--[[- Pause execution of the current thread and waits for events, including the
+`terminate` event.
+
+This behaves almost the same as @{os.pullEvent}, except it allows you to handle
+the `terminate` event yourself - the program will not stop execution when
+<kbd>Ctrl+T</kbd> is pressed.
+
+@tparam[opt] string filter Event to filter for.
+@treturn string event The name of the event that fired.
+@treturn any param... Optional additional parameters of the event.
+@usage Listen for `terminate` events.
+
+    while true do
+        local event = os.pullEventRaw()
+        if event == "terminate" then
+            print("Caught terminate event!")
+        end
+    end
+
+@see os.pullEvent To pull events normally.
+]]
+function pullEventRaw(filter) end
+
+--- Pauses execution for the specified number of seconds, alias of @{_G.sleep}.
+function sleep(time) end
+
+--- Get the current CraftOS version (for example, `CraftOS 1.8`).
+--
+-- This is defined by `bios.lua`. For the current version of CC:Tweaked, this
+-- should return `CraftOS 1.8`.
+--
+-- @treturn string The current CraftOS version.
+function version() end
+
+--[[- Run the program at the given path with the specified environment and
+arguments.
+
+This function does not resolve program names like the shell does. This means
+that, for example, `os.run("edit")` will not work. As well as this, it does not
+provide access to the @{shell} API in the environment. For this behaviour, use
+@{shell.run} instead.
+
+If the program cannot be found, or failed to run, it will print the error and
+return `false`. If you want to handle this more gracefully, use an alternative
+such as @{loadfile}.
+
+@tparam table env The environment to run the program with.
+@tparam string path The exact path of the program to run.
+@param ... The arguments to pass to the program.
+@treturn boolean Whether or not the program ran successfully.
+@usage Run the default shell from within your program:
+
+    os.run({}, "/rom/programs/shell")
+
+@see shell.run
+@see loadfile
+]]
+function run(env, path, ...) end

doc/stub/redstone.lua

@@ -1,14 +0,0 @@
-function getSides() end
-function setOutput(side, on) end
-function getOutput(side) end
-function getInput(side) end
-function setBundledOutput(side, output) end
-function getBundledOutput(side) end
-function getBundledInput(side) end
-function testBundledInput(side, mask) end
-function setAnalogOutput(side, value) end
-setAnalogueOutput = setAnalogOutput
-function getAnalogOutput(sid) end
-getAnalogueOutput = getAnalogOutput
-function getAnalogInput(side) end
-getAnalogueInput = getAnaloguInput

doc/stub/term.lua

@@ -1,52 +0,0 @@
-function write(text) end
-function scroll(lines) end
-function setCursorPos(x, y) end
-function setCursorBlink(blink) end
-function getCursorPos() end
-function getSize() end
-function clear() end
-function clearLine() end
-function setTextColour(colour) end
-setTextColor = setTextColour
-function setBackgroundColour(colour) end
-setBackgroundColor = setBackgroundColour
-function isColour() end
-isColor = isColour
-function getTextColour() end
-getTextColor = getTextColor
-function getBackgroundColour() end
-getBackgroundColour = getBackgroundColour
-function blit(text, text_colours, background_colours) end
-function setPaletteColour(colour, ...) end
-setPaletteColour = setPaletteColour
-function getPaletteColour(colour, ...) end
-getPaletteColour = getPaletteColour
-function nativePaletteColour(colour) end
-nativePaletteColour = nativePaletteColour
-
---- @type Redirect
-local Redirect = {}
-
-Redirect.write = write
-Redirect.scroll = scroll
-Redirect.setCursorPos = setCursorPos
-Redirect.setCursorBlink = setCursorBlink
-Redirect.getCursorPos = getCursorPos
-Redirect.getSize = getSize
-Redirect.clear = clear
-Redirect.clearLine = clearLine
-Redirect.setTextColour = setTextColour
-Redirect.setTextColor = setTextColor
-Redirect.setBackgroundColour = setBackgroundColour
-Redirect.setBackgroundColor = setBackgroundColor
-Redirect.isColour = isColour
-Redirect.isColor = isColor
-Redirect.getTextColour = getTextColour
-Redirect.getTextColor = getTextColor
-Redirect.getBackgroundColour = getBackgroundColour
-Redirect.getBackgroundColor = getBackgroundColor
-Redirect.blit = blit
-Redirect.setPaletteColour = setPaletteColour
-Redirect.setPaletteColor = setPaletteColor
-Redirect.getPaletteColour = getPaletteColour
-Redirect.getPaletteColor = getPaletteColor

doc/stub/turtle.lua

@@ -1,230 +1 @@
---- Move the turtle forward one block.
--- @treturn boolean Whether the turtle could successfully move.
--- @treturn string|nil The reason the turtle could not move.
-function forward() end
-
---- Move the turtle backwards one block.
--- @treturn boolean Whether the turtle could successfully move.
--- @treturn string|nil The reason the turtle could not move.
-function back() end
-
---- Move the turtle up one block.
--- @treturn boolean Whether the turtle could successfully move.
--- @treturn string|nil The reason the turtle could not move.
-function up() end
-
---- Move the turtle down one block.
--- @treturn boolean Whether the turtle could successfully move.
--- @treturn string|nil The reason the turtle could not move.
-function down() end
-
---- Rotate the turtle 90 degress to the left.
-function turnLeft() end
-
---- Rotate the turtle 90 degress to the right.
-function turnRight() end
-
---- Attempt to break the block in front of the turtle.
---
--- This requires a turtle tool capable of breaking the block. Diamond pickaxes
--- (mining turtles) can break any vanilla block, but other tools (such as axes)
--- are more limited.
---
--- @tparam[opt] "left"|"right" side The specific tool to use.
--- @treturn boolean Whether a block was broken.
--- @treturn string|nil The reason no block was broken.
-function dig(side) end
-
---- Attempt to break the block above the turtle. See @{dig} for full details.
---
--- @tparam[opt] "left"|"right" side The specific tool to use.
--- @treturn boolean Whether a block was broken.
--- @treturn string|nil The reason no block was broken.
-function digUp(side) end
-
---- Attempt to break the block below the turtle. See @{dig} for full details.
---
--- @tparam[opt] "left"|"right" side The specific tool to use.
--- @treturn boolean Whether a block was broken.
--- @treturn string|nil The reason no block was broken.
-function digDown(side) end
-
---- Attack the entity in front of the turtle.
---
--- @tparam[opt] "left"|"right" side The specific tool to use.
--- @treturn boolean Whether an entity was attacked.
--- @treturn string|nil The reason nothing was attacked.
-function attack(side) end
-
---- Attack the entity above the turtle.
---
--- @tparam[opt] "left"|"right" side The specific tool to use.
--- @treturn boolean Whether an entity was attacked.
--- @treturn string|nil The reason nothing was attacked.
-function attackUp(side) end
-
---- Attack the entity below the turtle.
---
--- @tparam[opt] "left"|"right" side The specific tool to use.
--- @treturn boolean Whether an entity was attacked.
--- @treturn string|nil The reason nothing was attacked.
-function attackDown(side) end
-
---- Place a block or item into the world in front of the turtle.
---
--- @treturn boolean Whether the block could be placed.
--- @treturn string|nil The reason the block was not placed.
-function place() end
-
---- Place a block or item into the world above the turtle.
---
--- @treturn boolean Whether the block could be placed.
--- @treturn string|nil The reason the block was not placed.
-function placeUp() end
-
---- Place a block or item into the world below the turtle.
---
--- @treturn boolean Whether the block could be placed.
--- @treturn string|nil The reason the block was not placed.
-function placeDown() end
-
---- Drop the currently selected stack into the inventory in front of the turtle,
--- or as an item into the world if there is no inventory.
---
--- @tparam[opt] number count The number of items to drop. If not given, the
--- entire stack will be dropped.
--- @treturn boolean Whether items were dropped.
--- @treturn string|nil The reason the no items were dropped.
--- @see select
-function drop(count) end
-
---- Drop the currently selected stack into the inventory above the turtle, or as
--- an item into the world if there is no inventory.
---
--- @tparam[opt] number count The number of items to drop. If not given, the
--- entire stack will be dropped.
--- @treturn boolean Whether items were dropped.
--- @treturn string|nil The reason the no items were dropped.
--- @see select
-function dropUp(count) end
-
---- Drop the currently selected stack into the inventory below the turtle, or as
--- an item into the world if there is no inventory.
---
--- @tparam[opt] number count The number of items to drop. If not given, the
--- entire stack will be dropped.
--- @treturn boolean Whether items were dropped.
--- @treturn string|nil The reason the no items were dropped.
--- @see select
-function dropDown(count) end
-
---- Suck an item from the inventory in front of the turtle, or from an item
--- floating in the world.
---
--- This will pull items into the first acceptable slot, starting at the
--- @{select|currently selected} one.
---
--- @tparam[opt] number count The number of items to suck. If not given, up to a
--- stack of items will be picked up.
--- @treturn boolean Whether items were picked up.
--- @treturn string|nil The reason the no items were picked up.
-function suck(count) end
-
---- Suck an item from the inventory above the turtle, or from an item floating
--- in the world.
---
--- @tparam[opt] number count The number of items to suck. If not given, up to a
--- stack of items will be picked up.
--- @treturn boolean Whether items were picked up.
--- @treturn string|nil The reason the no items were picked up.
-function suckUp(count) end
-
---- Suck an item from the inventory below the turtle, or from an item floating
--- in the world.
---
--- @tparam[opt] number count The number of items to suck. If not given, up to a
--- stack of items will be picked up.
--- @treturn boolean Whether items were picked up.
--- @treturn string|nil The reason the no items were picked up.
-function suckDown(count) end
-
---- Check if there is a solid block in front of the turtle. In this case, solid
--- refers to any non-air or liquid block.
---
--- @treturn boolean If there is a solid block in front.
-function detect() end
-
---- Check if there is a solid block above the turtle.
---
--- @treturn boolean If there is a solid block above.
-function detectUp() end
-
---- Check if there is a solid block below the turtle.
---
--- @treturn boolean If there is a solid block below.
-function detectDown() end
-
-function compare() end
-function compareUp() end
-function compareDown() end
-
-function inspect() end
-function inspectUp() end
-function inspectDown() end
-
-
---- Change the currently selected slot.
---
--- The selected slot is determines what slot actions like @{drop} or
--- @{getItemCount} act on.
---
--- @tparam number slot The slot to select.
--- @see getSelectedSlot
-function select(slot) end
-
---- Get the currently selected slot.
---
--- @treturn number The current slot.
--- @see select
-function getSelectedSlot() end
-
---- Get the number of items in the given slot.
---
--- @tparam[opt] number slot The slot we wish to check. Defaults to the @{turtle.select|selected slot}.
--- @treturn number The number of items in this slot.
-function getItemCount(slot) end
-
---- Get the remaining number of items which may be stored in this stack.
---
--- For instance, if a slot contains 13 blocks of dirt, it has room for another 51.
---
--- @tparam[opt] number slot The slot we wish to check. Defaults to the @{turtle.select|selected slot}.
--- @treturn number The space left in this slot.
-function getItemSpace(slot) end
-
-
---- Get detailed information about the items in the given slot.
---
--- @tparam[opt] number slot The slot to get information about. Defaults to the @{turtle.select|selected slot}.
--- @treturn nil|table Information about the given slot, or @{nil} if it is empty.
--- @usage Print the current slot, assuming it contains 13 dirt.
---
---     print(textutils.serialize(turtle.getItemDetail()))
---     -- => {
---     --    name = "minecraft:dirt",
---     --    damage = 0,
---     --    count = 13,
---     -- }
-function getItemDetail(slot) end
-
-function getFuelLevel() end
-
-function refuel(count) end
-function compareTo(slot) end
-function transferTo(slot, count) end
-
-function getFuelLimit() end
-function equipLeft() end
-function equipRight() end
-
 function craft(limit) end

doc/styles.css

@@ -23,7 +23,7 @@ body {
                  "Droid Sans", "Helvetica Neue", Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
 }
 
-code, pre, .parameter, .type, .definition-name, .reference-code {
+code, pre, kbd, .parameter, .type, .definition-name, .reference-code {
     font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, Courier, monospace;
 }
 
@@ -51,7 +51,12 @@ h4 { font-size: 1.06em; }
 a, a:visited, a:active { font-weight: bold; color: #004080; text-decoration: none; }
 a:hover { text-decoration: underline; }
 
-blockquote { margin-left: 3em; }
+blockquote {
+    padding: 0.3em;
+    margin: 1em 0;
+    background: #f0f0f0;
+    border-left: solid 0.5em #ccc;
+}
 
 /* Stop sublists from having initial vertical space */
 ul ul { margin-top: 0px; }
@@ -106,7 +111,7 @@ footer {
 }
 
 /* The definition lists at the top of each page */
-table.definition-list {
+table.definition-list, table.pretty-table {
     border-collapse: collapse;
     width: 100%;
 }
@@ -123,8 +128,23 @@ table.definition-list th {
     text-align: right;
 }
 
+/* Deprecated definitions */
+table.definition-list tr.definition-deprecated th {
+    text-decoration: line-through;
+}
+
 table.definition-list td { width: 100%; }
 
+/* Pretty tables, mostly inherited from table.definition-list */
+table.pretty-table td, table.pretty-table th {
+    border: 1px solid #cccccc;
+    padding: 2px 4px;
+}
+
+table.pretty-table th {
+    background-color: #f0f0f0;
+}
+
 dl.definition dt {
     border-top: 1px solid #ccc;
     padding-top: 1em;
@@ -137,6 +157,10 @@ dl.definition dt .definition-name {
     flex-grow: 1;
 }
 
+/* Deprecated definitions */
+dl.definition dt .definition-name.definition-deprecated {
+    text-decoration: line-through;
+}
 
 dl.definition dd {
     padding-bottom: 1em;
@@ -168,6 +192,20 @@ span.parameter:after { content:":"; padding-left: 0.3em; }
     vertical-align: middle;
 }
 
+/** Fancy keyboard shortcut styling, inspired by GitHub markdown. */
+kbd {
+    display: inline-block;
+    padding: 4px 5px;
+    font-size: 0.8em;
+    line-height: 10px;
+    color: #444d56;
+    vertical-align: middle;
+    background-color: #fafbfc;
+    border: 1px solid #d1d5da;
+    border-radius: 3px;
+    box-shadow: inset 0 -1px 0 #d1d5da;
+}
+
 /* styles for prettification of source */
 .highlight .comment { color: #558817; }
 .highlight .constant { color: #a8660d; }

gradle.properties

@@ -1,7 +1,7 @@
 # Mod properties
-mod_version=1.87.0
+mod_version=1.93.1
 
 # Minecraft properties (update mods.toml when changing)
-mc_version=1.14.4
-forge_version=28.1.71
-mappings_version=20191123-1.14.3
+mc_version=1.16.3
+forge_version=34.0.1
+mappings_version=20200723-1.16.1

illuaminate.sexp

@@ -2,6 +2,7 @@
 
 (sources
   /doc/stub/
+  /doc/javadoc/
   /src/main/resources/*/computercraft/lua/bios.lua
   /src/main/resources/*/computercraft/lua/rom/
   /src/test/resources/test-rom)
@@ -12,8 +13,12 @@
   (index doc/index.md)
   (source-link https://github.com/SquidDev-CC/CC-Tweaked/blob/${commit}/${path}#L${line})
 
+  (module-kinds
+    (peripheral Peripherals))
+
   (library-path
     /doc/stub/
+    /doc/javadoc/
 
     /src/main/resources/*/computercraft/lua/rom/apis
     /src/main/resources/*/computercraft/lua/rom/apis/command
@@ -33,17 +38,27 @@
 
     ;; It's useful to name arguments for documentation, so we allow this. It'd
     ;; be good to find a compromise in the future, but this works for now.
-    -var:unused-arg
+    -var:unused-arg)
 
-    ;; Some APIS (keys, colour and os mainly) are incomplete right now.
-    -var:unresolved-member)
   (lint
     (bracket-spaces
       (call no-space)
       (function-args no-space)
       (parens no-space)
       (table space)
-      (index no-space))))
+      (index no-space))
+
+    ;; colours imports from colors, and we don't handle that right now.
+    ;; keys is entirely dynamic, so we skip it.
+    (dynamic-modules colours keys _G)
+
+    (globals
+      :max
+      _CC_DEFAULT_SETTINGS
+      _CC_DISABLE_LUA51_FEATURES
+      ;; Ideally we'd pick these up from bios.lua, but illuaminate currently
+      ;; isn't smart enough.
+      sleep write printError read rs)))
 
 ;; We disable the unused global linter in bios.lua and the APIs. In the future
 ;; hopefully we'll get illuaminate to handle this.
@@ -54,31 +69,47 @@
   (lint (allow-toplevel-global true)))
 
 ;; Silence some variable warnings in documentation stubs.
-(at /doc/stub
+(at (/doc/stub/ /doc/javadoc/)
   (linters -var:unused-global)
   (lint (allow-toplevel-global true)))
 
 ;; Suppress warnings for currently undocumented modules.
 (at
-  (/doc/stub/commands.lua
-   /doc/stub/fs.lua
+  (; Java APIs
    /doc/stub/http.lua
    /doc/stub/os.lua
-   /doc/stub/redstone.lua
-   /doc/stub/term.lua
    /doc/stub/turtle.lua
-   /src/main/resources/*/computercraft/lua/rom/apis/command/commands.lua
+   /doc/stub/global.lua
+   ; Java generated APIs
+   /doc/javadoc/turtle.lua
+   ; Peripherals
+   /doc/javadoc/drive.lua
+   /doc/javadoc/speaker.lua
+   /doc/javadoc/printer.lua
+   ; Lua APIs
    /src/main/resources/*/computercraft/lua/rom/apis/io.lua
-   /src/main/resources/*/computercraft/lua/rom/apis/window.lua
-   /src/main/resources/*/computercraft/lua/rom/modules/main/cc/shell/completion.lua)
+   /src/main/resources/*/computercraft/lua/rom/apis/window.lua)
 
-  (linters -doc:undocumented -doc:undocumented-arg))
+  (linters -doc:undocumented -doc:undocumented-arg -doc:undocumented-return))
 
 ;; These currently rely on unknown references.
 (at
   (/src/main/resources/*/computercraft/lua/rom/apis/textutils.lua
    /src/main/resources/*/computercraft/lua/rom/modules/main/cc/completion.lua
    /src/main/resources/*/computercraft/lua/rom/modules/main/cc/shell/completion.lua
-   /src/main/resources/*/computercraft/lua/rom/programs/advanced/multishell.lua
-   /src/main/resources/*/computercraft/lua/rom/programs/shell.lua)
+   /src/main/resources/*/computercraft/lua/rom/programs/shell.lua
+   /doc/stub/fs.lua)
   (linters -doc:unresolved-reference))
+
+;; Suppress warnings for the BIOS using its own deprecated members for now.
+(at /src/main/resources/*/computercraft/lua/bios.lua
+  (linters -var:deprecated))
+
+(at /src/test/resources/test-rom
+  ; We should still be able to test deprecated members.
+  (linters -var:deprecated)
+
+  (lint
+    (globals
+      :max sleep write
+      cct_test describe expect howlci fail it pending stub)))

src/generated/resources/data/computercraft/loot_tables/blocks/computer_advanced.json

@@ -1,4 +1,5 @@
 {
+  "type": "minecraft:block",
   "pools": [
     {
       "name": "main",
@@ -16,6 +17,9 @@
             {
               "condition": "computercraft:block_named"
             },
+            {
+              "condition": "computercraft:has_id"
+            },
             {
               "condition": "minecraft:inverted",
               "term": {

src/generated/resources/data/computercraft/loot_tables/blocks/computer_normal.json

@@ -1,4 +1,5 @@
 {
+  "type": "minecraft:block",
   "pools": [
     {
       "name": "main",
@@ -16,6 +17,9 @@
             {
               "condition": "computercraft:block_named"
             },
+            {
+              "condition": "computercraft:has_id"
+            },
             {
               "condition": "minecraft:inverted",
               "term": {

src/generated/resources/data/computercraft/loot_tables/blocks/disk_drive.json

@@ -1,4 +1,5 @@
 {
+  "type": "minecraft:block",
   "pools": [
     {
       "name": "main",

src/generated/resources/data/computercraft/loot_tables/blocks/monitor_advanced.json

@@ -1,4 +1,5 @@
 {
+  "type": "minecraft:block",
   "pools": [
     {
       "name": "main",

src/generated/resources/data/computercraft/loot_tables/blocks/monitor_normal.json

@@ -1,4 +1,5 @@
 {
+  "type": "minecraft:block",
   "pools": [
     {
       "name": "main",

src/generated/resources/data/computercraft/loot_tables/blocks/printer.json

@@ -1,4 +1,5 @@
 {
+  "type": "minecraft:block",
   "pools": [
     {
       "name": "main",

src/generated/resources/data/computercraft/loot_tables/blocks/speaker.json

@@ -1,4 +1,5 @@
 {
+  "type": "minecraft:block",
   "pools": [
     {
       "name": "main",

src/generated/resources/data/computercraft/loot_tables/blocks/turtle_advanced.json

@@ -1,4 +1,5 @@
 {
+  "type": "minecraft:block",
   "pools": [
     {
       "name": "main",
@@ -16,6 +17,9 @@
             {
               "condition": "computercraft:block_named"
             },
+            {
+              "condition": "computercraft:has_id"
+            },
             {
               "condition": "minecraft:inverted",
               "term": {

src/generated/resources/data/computercraft/loot_tables/blocks/turtle_normal.json

@@ -1,4 +1,5 @@
 {
+  "type": "minecraft:block",
   "pools": [
     {
       "name": "main",
@@ -16,6 +17,9 @@
             {
               "condition": "computercraft:block_named"
             },
+            {
+              "condition": "computercraft:has_id"
+            },
             {
               "condition": "minecraft:inverted",
               "term": {

src/generated/resources/data/computercraft/loot_tables/blocks/wired_modem_full.json

@@ -1,4 +1,5 @@
 {
+  "type": "minecraft:block",
   "pools": [
     {
       "name": "main",

src/generated/resources/data/computercraft/loot_tables/blocks/wireless_modem_advanced.json

@@ -1,4 +1,5 @@
 {
+  "type": "minecraft:block",
   "pools": [
     {
       "name": "main",

src/generated/resources/data/computercraft/loot_tables/blocks/wireless_modem_normal.json

@@ -1,4 +1,5 @@
 {
+  "type": "minecraft:block",
   "pools": [
     {
       "name": "main",

src/generated/resources/data/computercraft/loot_tables/treasure_disk.json

@@ -0,0 +1 @@
+{}

src/generated/resources/data/minecraft/tags/items/piglin_loved.json

@@ -0,0 +1,10 @@
+{
+  "replace": false,
+  "values": [
+    "computercraft:computer_advanced",
+    "computercraft:turtle_advanced",
+    "computercraft:wireless_modem_advanced",
+    "computercraft:pocket_computer_advanced",
+    "computercraft:monitor_advanced"
+  ]
+}

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

@@ -6,53 +6,40 @@
 package dan200.computercraft;
 
 import dan200.computercraft.api.turtle.event.TurtleAction;
-import dan200.computercraft.core.apis.AddressPredicate;
+import dan200.computercraft.core.apis.http.options.Action;
+import dan200.computercraft.core.apis.http.options.AddressRule;
+import dan200.computercraft.core.asm.GenericSource;
 import dan200.computercraft.shared.Config;
-import dan200.computercraft.shared.computer.blocks.BlockComputer;
+import dan200.computercraft.shared.Registry;
 import dan200.computercraft.shared.computer.core.ClientComputerRegistry;
 import dan200.computercraft.shared.computer.core.ServerComputerRegistry;
-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.peripheral.diskdrive.BlockDiskDrive;
-import dan200.computercraft.shared.peripheral.modem.wired.BlockCable;
-import dan200.computercraft.shared.peripheral.modem.wired.BlockWiredModemFull;
-import dan200.computercraft.shared.peripheral.modem.wired.ItemBlockCable;
-import dan200.computercraft.shared.peripheral.modem.wireless.BlockWirelessModem;
-import dan200.computercraft.shared.peripheral.monitor.BlockMonitor;
 import dan200.computercraft.shared.peripheral.monitor.MonitorRenderer;
-import dan200.computercraft.shared.peripheral.printer.BlockPrinter;
-import dan200.computercraft.shared.peripheral.speaker.BlockSpeaker;
-import dan200.computercraft.shared.pocket.items.ItemPocketComputer;
 import dan200.computercraft.shared.pocket.peripherals.PocketModem;
 import dan200.computercraft.shared.pocket.peripherals.PocketSpeaker;
-import dan200.computercraft.shared.turtle.blocks.BlockTurtle;
-import dan200.computercraft.shared.turtle.items.ItemTurtle;
 import dan200.computercraft.shared.turtle.upgrades.*;
-import net.minecraft.resources.IReloadableResourceManager;
-import net.minecraft.util.ResourceLocation;
+import dan200.computercraft.shared.util.ServiceUtil;
 import net.minecraftforge.fml.common.Mod;
-import net.minecraftforge.fml.server.ServerLifecycleHooks;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
-import java.io.IOException;
-import java.io.InputStream;
+import java.util.Collections;
 import java.util.EnumSet;
+import java.util.List;
+import java.util.Objects;
 import java.util.concurrent.TimeUnit;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
 
 @Mod( ComputerCraft.MOD_ID )
 public final class ComputerCraft
 {
     public static final String MOD_ID = "computercraft";
 
-    public static final int DATAFIXER_VERSION = 0;
-
     // Configuration options
-    public static final String[] DEFAULT_HTTP_WHITELIST = new String[] { "*" };
-    public static final String[] DEFAULT_HTTP_BLACKLIST = new String[] {
+    public static final String[] DEFAULT_HTTP_ALLOW = new String[] { "*" };
+    public static final String[] DEFAULT_HTTP_DENY = new String[] {
         "127.0.0.0/8",
+        "0.0.0.0/8",
         "10.0.0.0/8",
         "172.16.0.0/12",
         "192.168.0.0/16",
@@ -62,34 +49,39 @@ public final class ComputerCraft
     public static int computerSpaceLimit = 1000 * 1000;
     public static int floppySpaceLimit = 125 * 1000;
     public static int maximumFilesOpen = 128;
-    public static boolean disable_lua51_features = false;
-    public static String default_computer_settings = "";
-    public static boolean debug_enable = true;
-    public static boolean logPeripheralErrors = false;
+    public static boolean disableLua51Features = false;
+    public static String defaultComputerSettings = "";
+    public static boolean debugEnable = true;
+    public static boolean logComputerErrors = true;
+    public static boolean commandRequireCreative = true;
 
-    public static int computer_threads = 1;
+    public static int computerThreads = 1;
     public static long maxMainGlobalTime = TimeUnit.MILLISECONDS.toNanos( 10 );
     public static long maxMainComputerTime = TimeUnit.MILLISECONDS.toNanos( 5 );
 
-    public static boolean http_enable = true;
-    public static boolean http_websocket_enable = true;
-    public static AddressPredicate http_whitelist = new AddressPredicate( DEFAULT_HTTP_WHITELIST );
-    public static AddressPredicate http_blacklist = new AddressPredicate( DEFAULT_HTTP_BLACKLIST );
+    public static boolean httpEnabled = true;
+    public static boolean httpWebsocketEnabled = true;
+    public static List<AddressRule> httpRules = Collections.unmodifiableList( Stream.concat(
+        Stream.of( DEFAULT_HTTP_DENY )
+            .map( x -> AddressRule.parse( x, null, Action.DENY.toPartial() ) )
+            .filter( Objects::nonNull ),
+        Stream.of( DEFAULT_HTTP_ALLOW )
+            .map( x -> AddressRule.parse( x, null, Action.ALLOW.toPartial() ) )
+            .filter( Objects::nonNull )
+    ).collect( Collectors.toList() ) );
 
-    public static int httpTimeout = 30000;
     public static int httpMaxRequests = 16;
-    public static long httpMaxDownload = 16 * 1024 * 1024;
-    public static long httpMaxUpload = 4 * 1024 * 1024;
     public static int httpMaxWebsockets = 4;
-    public static int httpMaxWebsocketMessage = 128 * 1024;
 
     public static boolean enableCommandBlock = false;
-    public static int modem_range = 64;
-    public static int modem_highAltitudeRange = 384;
-    public static int modem_rangeDuringStorm = 64;
-    public static int modem_highAltitudeRangeDuringStorm = 384;
+    public static int modemRange = 64;
+    public static int modemHighAltitudeRange = 384;
+    public static int modemRangeDuringStorm = 64;
+    public static int modemHighAltitudeRangeDuringStorm = 384;
     public static int maxNotesPerTick = 8;
     public static MonitorRenderer monitorRenderer = MonitorRenderer.BEST;
+    public static double monitorDistanceSq = 4096;
+    public static long monitorBandwidth = 1_000_000;
 
     public static boolean turtlesNeedFuel = true;
     public static int turtleFuelLimit = 20000;
@@ -98,61 +90,19 @@ public final class ComputerCraft
     public static boolean turtlesCanPush = true;
     public static EnumSet<TurtleAction> turtleDisabledActions = EnumSet.noneOf( TurtleAction.class );
 
-    public static final int terminalWidth_computer = 51;
-    public static final int terminalHeight_computer = 19;
+    public static boolean genericPeripheral = false;
 
-    public static final int terminalWidth_turtle = 39;
-    public static final int terminalHeight_turtle = 13;
+    public static int computerTermWidth = 51;
+    public static int computerTermHeight = 19;
 
-    public static final int terminalWidth_pocketComputer = 26;
-    public static final int terminalHeight_pocketComputer = 20;
+    public static final int turtleTermWidth = 39;
+    public static final int turtleTermHeight = 13;
 
-    // Blocks and Items
-    public static final class Blocks
-    {
-        public static BlockComputer computerNormal;
-        public static BlockComputer computerAdvanced;
-        public static BlockComputer computerCommand;
+    public static int pocketTermWidth = 26;
+    public static int pocketTermHeight = 20;
 
-        public static BlockTurtle turtleNormal;
-        public static BlockTurtle turtleAdvanced;
-
-        public static BlockSpeaker speaker;
-        public static BlockDiskDrive diskDrive;
-        public static BlockPrinter printer;
-
-        public static BlockMonitor monitorNormal;
-        public static BlockMonitor monitorAdvanced;
-
-        public static BlockWirelessModem wirelessModemNormal;
-        public static BlockWirelessModem wirelessModemAdvanced;
-
-        public static BlockWiredModemFull wiredModemFull;
-        public static BlockCable cable;
-    }
-
-    public static final class Items
-    {
-        public static ItemComputer computerNormal;
-        public static ItemComputer computerAdvanced;
-        public static ItemComputer computerCommand;
-
-        public static ItemPocketComputer pocketComputerNormal;
-        public static ItemPocketComputer pocketComputerAdvanced;
-
-        public static ItemTurtle turtleNormal;
-        public static ItemTurtle turtleAdvanced;
-
-        public static ItemDisk disk;
-        public static ItemTreasureDisk treasureDisk;
-
-        public static ItemPrintout printedPage;
-        public static ItemPrintout printedPages;
-        public static ItemPrintout printedBook;
-
-        public static ItemBlockCable.Cable cable;
-        public static ItemBlockCable.WiredModem wiredModem;
-    }
+    public static int monitorWidth = 8;
+    public static int monitorHeight = 6;
 
     public static final class TurtleUpgrades
     {
@@ -184,24 +134,8 @@ public final class ComputerCraft
 
     public ComputerCraft()
     {
-        Config.load();
-    }
-
-    public static String getVersion()
-    {
-        return "${version}";
-    }
-
-    public static InputStream getResourceFile( String domain, String subPath )
-    {
-        IReloadableResourceManager manager = ServerLifecycleHooks.getCurrentServer().getResourceManager();
-        try
-        {
-            return manager.getResource( new ResourceLocation( domain, subPath ) ).getInputStream();
-        }
-        catch( IOException ignored )
-        {
-            return null;
-        }
+        Config.setup();
+        Registry.setup();
+        GenericSource.setup( () -> ServiceUtil.loadServicesForge( GenericSource.class ) );
     }
 }

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

@@ -5,7 +5,6 @@
  */
 package dan200.computercraft;
 
-import com.google.common.collect.MapMaker;
 import dan200.computercraft.api.ComputerCraftAPI.IComputerCraftAPI;
 import dan200.computercraft.api.filesystem.IMount;
 import dan200.computercraft.api.filesystem.IWritableMount;
@@ -24,7 +23,6 @@ import dan200.computercraft.core.filesystem.ResourceMount;
 import dan200.computercraft.shared.*;
 import dan200.computercraft.shared.peripheral.modem.wireless.WirelessNetwork;
 import dan200.computercraft.shared.util.IDAssigner;
-import dan200.computercraft.shared.wired.CapabilityWiredElement;
 import dan200.computercraft.shared.wired.WiredNode;
 import net.minecraft.resources.IReloadableResourceManager;
 import net.minecraft.tileentity.TileEntity;
@@ -34,29 +32,47 @@ import net.minecraft.util.math.BlockPos;
 import net.minecraft.world.IBlockReader;
 import net.minecraft.world.World;
 import net.minecraftforge.common.util.LazyOptional;
+import net.minecraftforge.fml.ModList;
 import net.minecraftforge.fml.server.ServerLifecycleHooks;
 
 import javax.annotation.Nonnull;
 import java.io.File;
-import java.lang.ref.WeakReference;
-import java.util.Map;
+import java.io.IOException;
+import java.io.InputStream;
+
+import static dan200.computercraft.shared.Capabilities.CAPABILITY_WIRED_ELEMENT;
 
 public final class ComputerCraftAPIImpl implements IComputerCraftAPI
 {
     public static final ComputerCraftAPIImpl INSTANCE = new ComputerCraftAPIImpl();
 
+    private String version;
+
     private ComputerCraftAPIImpl()
     {
     }
 
-    private WeakReference<IReloadableResourceManager> currentResources;
-    private final Map<ResourceLocation, ResourceMount> mountCache = new MapMaker().weakValues().concurrencyLevel( 1 ).makeMap();
+    public static InputStream getResourceFile( String domain, String subPath )
+    {
+        IReloadableResourceManager manager = (IReloadableResourceManager) ServerLifecycleHooks.getCurrentServer().getDataPackRegistries().getResourceManager();
+        try
+        {
+            return manager.getResource( new ResourceLocation( domain, subPath ) ).getInputStream();
+        }
+        catch( IOException ignored )
+        {
+            return null;
+        }
+    }
 
     @Nonnull
     @Override
     public String getInstalledVersion()
     {
-        return "${version}";
+        if( version != null ) return version;
+        return version = ModList.get().getModContainerById( ComputerCraft.MOD_ID )
+            .map( x -> x.getModInfo().getVersion().toString() )
+            .orElse( "unknown" );
     }
 
     @Override
@@ -81,7 +97,7 @@ public final class ComputerCraftAPIImpl implements IComputerCraftAPI
     @Override
     public IMount createResourceMount( @Nonnull String domain, @Nonnull String subPath )
     {
-        IReloadableResourceManager manager = ServerLifecycleHooks.getCurrentServer().getResourceManager();
+        IReloadableResourceManager manager = (IReloadableResourceManager) ServerLifecycleHooks.getCurrentServer().getDataPackRegistries().getResourceManager();
         ResourceMount mount = ResourceMount.get( domain, subPath, manager );
         return mount.exists( "" ) ? mount : null;
     }
@@ -147,6 +163,6 @@ public final class ComputerCraftAPIImpl implements IComputerCraftAPI
     public LazyOptional<IWiredElement> getWiredElementAt( @Nonnull IBlockReader world, @Nonnull BlockPos pos, @Nonnull Direction side )
     {
         TileEntity tile = world.getTileEntity( pos );
-        return tile == null ? LazyOptional.empty() : tile.getCapability( CapabilityWiredElement.CAPABILITY, side );
+        return tile == null ? LazyOptional.empty() : tile.getCapability( CAPABILITY_WIRED_ELEMENT, side );
     }
 }

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

@@ -1,79 +0,0 @@
-/*
- * This file is part of the public ComputerCraft API - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2020. 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.api.turtle.ITurtleUpgrade;
-import dan200.computercraft.api.turtle.TurtleUpgradeType;
-import net.minecraft.item.ItemStack;
-import net.minecraft.util.IItemProvider;
-import net.minecraft.util.ResourceLocation;
-import net.minecraft.util.Util;
-
-import javax.annotation.Nonnull;
-
-/**
- * A base class for {@link ITurtleUpgrade}s.
- *
- * One does not have to use this, but it does provide a convenient template.
- */
-public abstract class AbstractTurtleUpgrade implements ITurtleUpgrade
-{
-    private final ResourceLocation id;
-    private final TurtleUpgradeType type;
-    private final String adjective;
-    private final ItemStack stack;
-
-    protected AbstractTurtleUpgrade( ResourceLocation id, TurtleUpgradeType type, String adjective, ItemStack stack )
-    {
-        this.id = id;
-        this.type = type;
-        this.adjective = adjective;
-        this.stack = stack;
-    }
-
-    protected AbstractTurtleUpgrade( ResourceLocation id, TurtleUpgradeType type, String adjective, IItemProvider item )
-    {
-        this( id, type, adjective, new ItemStack( item ) );
-    }
-
-    protected AbstractTurtleUpgrade( ResourceLocation id, TurtleUpgradeType type, ItemStack stack )
-    {
-        this( id, type, Util.makeTranslationKey( "upgrade", id ) + ".adjective", stack );
-    }
-
-    protected AbstractTurtleUpgrade( ResourceLocation id, TurtleUpgradeType type, IItemProvider item )
-    {
-        this( id, type, new ItemStack( item ) );
-    }
-
-    @Nonnull
-    @Override
-    public final ResourceLocation getUpgradeID()
-    {
-        return id;
-    }
-
-    @Nonnull
-    @Override
-    public final String getUnlocalisedAdjective()
-    {
-        return adjective;
-    }
-
-    @Nonnull
-    @Override
-    public final TurtleUpgradeType getType()
-    {
-        return type;
-    }
-
-    @Nonnull
-    @Override
-    public final ItemStack getCraftingItem()
-    {
-        return stack;
-    }
-}

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

@@ -43,9 +43,10 @@ public final class ComputerCraftAPI
     }
 
     @Nonnull
+    @Deprecated
     public static String getAPIVersion()
     {
-        return "${version}";
+        return getInstalledVersion();
     }
 
     /**
@@ -112,31 +113,6 @@ public final class ComputerCraftAPI
         return getInstance().createResourceMount( domain, subPath );
     }
 
-    /**
-     * Creates a file system mount to a resource folder, and returns it.
-     *
-     * Use in conjunction with {@link IComputerAccess#mount} or {@link IComputerAccess#mountWritable} to mount a
-     * resource folder onto a computer's file system.
-     *
-     * The files in this mount will be a combination of files in all mod jar, and data packs that contain
-     * resources with the same domain and path.
-     *
-     * @param klass   The mod class to which the files belong.
-     * @param domain  The domain under which to look for resources. eg: "mymod".
-     * @param subPath The subPath under which to look for resources. eg: "lua/myfiles".
-     * @return The mount, or {@code null} if it could be created for some reason.
-     * @see IComputerAccess#mount(String, IMount)
-     * @see IComputerAccess#mountWritable(String, IWritableMount)
-     * @see IMount
-     * @deprecated Use {@link #createResourceMount(String, String)} instead.
-     */
-    @Nullable
-    @Deprecated
-    public static IMount createResourceMount( Class<?> klass, @Nonnull String domain, @Nonnull String subPath )
-    {
-        return getInstance().createResourceMount( domain, subPath );
-    }
-
     /**
      * Registers a peripheral provider to convert blocks into {@link IPeripheral} implementations.
      *

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

@@ -0,0 +1,61 @@
+/*
+ * This file is part of the public ComputerCraft API - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2020. 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 net.minecraft.client.Minecraft;
+import net.minecraft.client.renderer.model.IBakedModel;
+import net.minecraft.client.renderer.model.ModelManager;
+import net.minecraft.client.renderer.model.ModelResourceLocation;
+import net.minecraft.item.ItemStack;
+import net.minecraft.util.math.vector.TransformationMatrix;
+
+import javax.annotation.Nonnull;
+import java.util.Objects;
+
+/**
+ * A model to render, combined with a transformation matrix to apply.
+ */
+public final class TransformedModel
+{
+    private final IBakedModel model;
+    private final TransformationMatrix matrix;
+
+    public TransformedModel( @Nonnull IBakedModel model, @Nonnull TransformationMatrix matrix )
+    {
+        this.model = Objects.requireNonNull( model );
+        this.matrix = Objects.requireNonNull( matrix );
+    }
+
+    public TransformedModel( @Nonnull IBakedModel model )
+    {
+        this.model = Objects.requireNonNull( model );
+        this.matrix = TransformationMatrix.identity();
+    }
+
+    public static TransformedModel of( @Nonnull ModelResourceLocation location )
+    {
+        ModelManager modelManager = Minecraft.getInstance().getModelManager();
+        return new TransformedModel( modelManager.getModel( location ) );
+    }
+
+    public static TransformedModel of( @Nonnull ItemStack item, @Nonnull TransformationMatrix transform )
+    {
+        IBakedModel model = Minecraft.getInstance().getItemRenderer().getItemModelMesher().getItemModel( item );
+        return new TransformedModel( model, transform );
+    }
+
+    @Nonnull
+    public IBakedModel getModel()
+    {
+        return model;
+    }
+
+    @Nonnull
+    public TransformationMatrix getMatrix()
+    {
+        return matrix;
+    }
+}

src/main/java/dan200/computercraft/api/filesystem/IMount.java

@@ -11,8 +11,6 @@ import net.minecraft.world.World;
 
 import javax.annotation.Nonnull;
 import java.io.IOException;
-import java.io.InputStream;
-import java.nio.channels.Channels;
 import java.nio.channels.ReadableByteChannel;
 import java.nio.file.attribute.BasicFileAttributes;
 import java.util.List;
@@ -23,10 +21,10 @@ import java.util.List;
  *
  * Ready made implementations of this interface can be created using
  * {@link ComputerCraftAPI#createSaveDirMount(World, String, long)} or
- * {@link ComputerCraftAPI#createResourceMount(Class, String, String)}, or you're free to implement it yourselves!
+ * {@link ComputerCraftAPI#createResourceMount(String, String)}, or you're free to implement it yourselves!
  *
  * @see ComputerCraftAPI#createSaveDirMount(World, String, long)
- * @see ComputerCraftAPI#createResourceMount(Class, String, String)
+ * @see ComputerCraftAPI#createResourceMount(String, String)
  * @see IComputerAccess#mount(String, IMount)
  * @see IWritableMount
  */
@@ -68,18 +66,6 @@ public interface IMount
      */
     long getSize( @Nonnull String path ) throws IOException;
 
-    /**
-     * Opens a file with a given path, and returns an {@link InputStream} representing its contents.
-     *
-     * @param path A file path in normalised format, relative to the mount location. ie: "programs/myprogram".
-     * @return A stream representing the contents of the file.
-     * @throws IOException If the file does not exist, or could not be opened.
-     * @deprecated Use {@link #openChannelForRead(String)} instead
-     */
-    @Nonnull
-    @Deprecated
-    InputStream openForRead( @Nonnull String path ) throws IOException;
-
     /**
      * Opens a file with a given path, and returns an {@link ReadableByteChannel} representing its contents.
      *
@@ -90,10 +76,7 @@ public interface IMount
      * @throws IOException If the file does not exist, or could not be opened.
      */
     @Nonnull
-    default ReadableByteChannel openChannelForRead( @Nonnull String path ) throws IOException
-    {
-        return Channels.newChannel( openForRead( path ) );
-    }
+    ReadableByteChannel openForRead( @Nonnull String path ) throws IOException;
 
     /**
      * Get attributes about the given file.

src/main/java/dan200/computercraft/api/filesystem/IWritableMount.java

@@ -12,7 +12,6 @@ import net.minecraft.world.World;
 import javax.annotation.Nonnull;
 import java.io.IOException;
 import java.io.OutputStream;
-import java.nio.channels.Channels;
 import java.nio.channels.WritableByteChannel;
 import java.util.OptionalLong;
 
@@ -46,18 +45,6 @@ public interface IWritableMount extends IMount
      */
     void delete( @Nonnull String path ) throws IOException;
 
-    /**
-     * Opens a file with a given path, and returns an {@link OutputStream} for writing to it.
-     *
-     * @param path A file path in normalised format, relative to the mount location. ie: "programs/myprogram".
-     * @return A stream for writing to
-     * @throws IOException If the file could not be opened for writing.
-     * @deprecated Use {@link #openChannelForWrite(String)} instead.
-     */
-    @Nonnull
-    @Deprecated
-    OutputStream openForWrite( @Nonnull String path ) throws IOException;
-
     /**
      * Opens a file with a given path, and returns an {@link OutputStream} for writing to it.
      *
@@ -67,22 +54,7 @@ public interface IWritableMount extends IMount
      * @throws IOException If the file could not be opened for writing.
      */
     @Nonnull
-    default WritableByteChannel openChannelForWrite( @Nonnull String path ) throws IOException
-    {
-        return Channels.newChannel( openForWrite( path ) );
-    }
-
-    /**
-     * Opens a file with a given path, and returns an {@link OutputStream} for appending to it.
-     *
-     * @param path A file path in normalised format, relative to the mount location. ie: "programs/myprogram".
-     * @return A stream for writing to.
-     * @throws IOException If the file could not be opened for writing.
-     * @deprecated Use {@link #openChannelForAppend(String)} instead.
-     */
-    @Nonnull
-    @Deprecated
-    OutputStream openForAppend( @Nonnull String path ) throws IOException;
+    WritableByteChannel openForWrite( @Nonnull String path ) throws IOException;
 
     /**
      * Opens a file with a given path, and returns an {@link OutputStream} for appending to it.
@@ -93,10 +65,7 @@ public interface IWritableMount extends IMount
      * @throws IOException If the file could not be opened for writing.
      */
     @Nonnull
-    default WritableByteChannel openChannelForAppend( @Nonnull String path ) throws IOException
-    {
-        return Channels.newChannel( openForAppend( path ) );
-    }
+    WritableByteChannel openForAppend( @Nonnull String path ) throws IOException;
 
     /**
      * Get the amount of free space on the mount, in bytes. You should decrease this value as the user writes to the

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

@@ -1,334 +0,0 @@
-/*
- * This file is part of the public ComputerCraft API - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2020. 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 dan200.computercraft.api.peripheral.IComputerAccess;
-import dan200.computercraft.api.peripheral.IPeripheral;
-
-import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
-import java.util.Map;
-
-/**
- * Provides methods for extracting values and validating Lua arguments, such as those provided to
- * {@link ILuaObject#callMethod(ILuaContext, int, Object[])} or
- * {@link IPeripheral#callMethod(IComputerAccess, ILuaContext, int, Object[])}.
- *
- * This provides two sets of functions: the {@code get*} methods, which require an argument to be valid, and
- * {@code opt*}, which accept a default value and return that if the argument was not present or was {@code null}.
- * If the argument is of the wrong type, a suitable error message will be thrown, with a similar format to Lua's own
- * error messages.
- *
- * <h2>Example usage:</h2>
- * <pre>
- * {@code
- * int slot = getInt( args, 0 );
- * int amount = optInt( args, 1, 64 );
- * }
- * </pre>
- */
-public final class ArgumentHelper
-{
-    private ArgumentHelper()
-    {
-    }
-
-    /**
-     * Get a string representation of the given value's type.
-     *
-     * @param value The value whose type we are trying to compute.
-     * @return A string representation of the given value's type, in a similar format to that provided by Lua's
-     * {@code type} function.
-     */
-    @Nonnull
-    public static String getType( @Nullable Object value )
-    {
-        if( value == null ) return "nil";
-        if( value instanceof String ) return "string";
-        if( value instanceof Boolean ) return "boolean";
-        if( value instanceof Number ) return "number";
-        if( value instanceof Map ) return "table";
-        return "userdata";
-    }
-
-    /**
-     * Construct a "bad argument" exception, from an expected type and the actual value provided.
-     *
-     * @param index    The argument number, starting from 0.
-     * @param expected The expected type for this argument.
-     * @param actual   The actual value provided for this argument.
-     * @return The constructed exception, which should be thrown immediately.
-     */
-    @Nonnull
-    public static LuaException badArgumentOf( int index, @Nonnull String expected, @Nullable Object actual )
-    {
-        return badArgument( index, expected, getType( actual ) );
-    }
-
-    /**
-     * Construct a "bad argument" exception, from an expected and actual type.
-     *
-     * @param index    The argument number, starting from 0.
-     * @param expected The expected type for this argument.
-     * @param actual   The provided type for this argument.
-     * @return The constructed exception, which should be thrown immediately.
-     */
-    @Nonnull
-    public static LuaException badArgument( int index, @Nonnull String expected, @Nonnull String actual )
-    {
-        return new LuaException( "bad argument #" + (index + 1) + " (" + expected + " expected, got " + actual + ")" );
-    }
-
-    /**
-     * Get an argument as a double.
-     *
-     * @param args  The arguments to extract from.
-     * @param index The index into the argument array to read from.
-     * @return The argument's value.
-     * @throws LuaException If the value is not a number.
-     * @see #getFiniteDouble(Object[], int) if you require this to be finite (i.e. not infinite or NaN).
-     */
-    public static double getDouble( @Nonnull Object[] args, int index ) throws LuaException
-    {
-        if( index >= args.length ) throw badArgument( index, "number", "nil" );
-        Object value = args[index];
-        if( !(value instanceof Number) ) throw badArgumentOf( index, "number", value );
-        return ((Number) value).doubleValue();
-    }
-
-    /**
-     * Get an argument as an integer.
-     *
-     * @param args  The arguments to extract from.
-     * @param index The index into the argument array to read from.
-     * @return The argument's value.
-     * @throws LuaException If the value is not an integer.
-     */
-    public static int getInt( @Nonnull Object[] args, int index ) throws LuaException
-    {
-        return (int) getLong( args, index );
-    }
-
-    /**
-     * Get an argument as a long.
-     *
-     * @param args  The arguments to extract from.
-     * @param index The index into the argument array to read from.
-     * @return The argument's value.
-     * @throws LuaException If the value is not a long.
-     */
-    public static long getLong( @Nonnull Object[] args, int index ) throws LuaException
-    {
-        if( index >= args.length ) throw badArgument( index, "number", "nil" );
-        Object value = args[index];
-        if( !(value instanceof Number) ) throw badArgumentOf( index, "number", value );
-        return checkFinite( index, (Number) value ).longValue();
-    }
-
-    /**
-     * Get an argument as a finite number (not infinite or NaN).
-     *
-     * @param args  The arguments to extract from.
-     * @param index The index into the argument array to read from.
-     * @return The argument's value.
-     * @throws LuaException If the value is not finite.
-     */
-    public static double getFiniteDouble( @Nonnull Object[] args, int index ) throws LuaException
-    {
-        return checkFinite( index, getDouble( args, index ) );
-    }
-
-    /**
-     * Get an argument as a boolean.
-     *
-     * @param args  The arguments to extract from.
-     * @param index The index into the argument array to read from.
-     * @return The argument's value.
-     * @throws LuaException If the value is not a boolean.
-     */
-    public static boolean getBoolean( @Nonnull Object[] args, int index ) throws LuaException
-    {
-        if( index >= args.length ) throw badArgument( index, "boolean", "nil" );
-        Object value = args[index];
-        if( !(value instanceof Boolean) ) throw badArgumentOf( index, "boolean", value );
-        return (Boolean) value;
-    }
-
-    /**
-     * Get an argument as a string.
-     *
-     * @param args  The arguments to extract from.
-     * @param index The index into the argument array to read from.
-     * @return The argument's value.
-     * @throws LuaException If the value is not a string.
-     */
-    @Nonnull
-    public static String getString( @Nonnull Object[] args, int index ) throws LuaException
-    {
-        if( index >= args.length ) throw badArgument( index, "string", "nil" );
-        Object value = args[index];
-        if( !(value instanceof String) ) throw badArgumentOf( index, "string", value );
-        return (String) value;
-    }
-
-    /**
-     * Get an argument as a table.
-     *
-     * @param args  The arguments to extract from.
-     * @param index The index into the argument array to read from.
-     * @return The argument's value.
-     * @throws LuaException If the value is not a table.
-     */
-    @Nonnull
-    public static Map<?, ?> getTable( @Nonnull Object[] args, int index ) throws LuaException
-    {
-        if( index >= args.length ) throw badArgument( index, "table", "nil" );
-        Object value = args[index];
-        if( !(value instanceof Map) ) throw badArgumentOf( index, "table", value );
-        return (Map<?, ?>) value;
-    }
-
-    /**
-     * Get an argument as a double.
-     *
-     * @param args  The arguments to extract from.
-     * @param index The index into the argument array to read from.
-     * @param def   The default value, if this argument is not given.
-     * @return The argument's value, or {@code def} if none was provided.
-     * @throws LuaException If the value is not a number.
-     */
-    public static double optDouble( @Nonnull Object[] args, int index, double def ) throws LuaException
-    {
-        Object value = index < args.length ? args[index] : null;
-        if( value == null ) return def;
-        if( !(value instanceof Number) ) throw badArgumentOf( index, "number", value );
-        return ((Number) value).doubleValue();
-    }
-
-    /**
-     * Get an argument as an int.
-     *
-     * @param args  The arguments to extract from.
-     * @param index The index into the argument array to read from.
-     * @param def   The default value, if this argument is not given.
-     * @return The argument's value, or {@code def} if none was provided.
-     * @throws LuaException If the value is not a number.
-     */
-    public static int optInt( @Nonnull Object[] args, int index, int def ) throws LuaException
-    {
-        return (int) optLong( args, index, def );
-    }
-
-    /**
-     * Get an argument as a long.
-     *
-     * @param args  The arguments to extract from.
-     * @param index The index into the argument array to read from.
-     * @param def   The default value, if this argument is not given.
-     * @return The argument's value, or {@code def} if none was provided.
-     * @throws LuaException If the value is not a number.
-     */
-    public static long optLong( @Nonnull Object[] args, int index, long def ) throws LuaException
-    {
-        Object value = index < args.length ? args[index] : null;
-        if( value == null ) return def;
-        if( !(value instanceof Number) ) throw badArgumentOf( index, "number", value );
-        return checkFinite( index, (Number) value ).longValue();
-    }
-
-    /**
-     * Get an argument as a finite number (not infinite or NaN).
-     *
-     * @param args  The arguments to extract from.
-     * @param index The index into the argument array to read from.
-     * @param def   The default value, if this argument is not given.
-     * @return The argument's value, or {@code def} if none was provided.
-     * @throws LuaException If the value is not finite.
-     */
-    public static double optFiniteDouble( @Nonnull Object[] args, int index, double def ) throws LuaException
-    {
-        return checkFinite( index, optDouble( args, index, def ) );
-    }
-
-    /**
-     * Get an argument as a boolean.
-     *
-     * @param args  The arguments to extract from.
-     * @param index The index into the argument array to read from.
-     * @param def   The default value, if this argument is not given.
-     * @return The argument's value, or {@code def} if none was provided.
-     * @throws LuaException If the value is not a boolean.
-     */
-    public static boolean optBoolean( @Nonnull Object[] args, int index, boolean def ) throws LuaException
-    {
-        Object value = index < args.length ? args[index] : null;
-        if( value == null ) return def;
-        if( !(value instanceof Boolean) ) throw badArgumentOf( index, "boolean", value );
-        return (Boolean) value;
-    }
-
-    /**
-     * Get an argument as a string.
-     *
-     * @param args  The arguments to extract from.
-     * @param index The index into the argument array to read from.
-     * @param def   The default value, if this argument is not given.
-     * @return The argument's value, or {@code def} if none was provided.
-     * @throws LuaException If the value is not a string.
-     */
-    public static String optString( @Nonnull Object[] args, int index, String def ) throws LuaException
-    {
-        Object value = index < args.length ? args[index] : null;
-        if( value == null ) return def;
-        if( !(value instanceof String) ) throw badArgumentOf( index, "string", value );
-        return (String) value;
-    }
-
-    /**
-     * Get an argument as a table.
-     *
-     * @param args  The arguments to extract from.
-     * @param index The index into the argument array to read from.
-     * @param def   The default value, if this argument is not given.
-     * @return The argument's value, or {@code def} if none was provided.
-     * @throws LuaException If the value is not a table.
-     */
-    public static Map<?, ?> optTable( @Nonnull Object[] args, int index, Map<Object, Object> def ) throws LuaException
-    {
-        Object value = index < args.length ? args[index] : null;
-        if( value == null ) return def;
-        if( !(value instanceof Map) ) throw badArgumentOf( index, "table", value );
-        return (Map<?, ?>) value;
-    }
-
-    private static Number checkFinite( int index, Number value ) throws LuaException
-    {
-        checkFinite( index, value.doubleValue() );
-        return value;
-    }
-
-    private static double checkFinite( int index, double value ) throws LuaException
-    {
-        if( !Double.isFinite( value ) ) throw badArgument( index, "number", getNumericType( value ) );
-        return value;
-    }
-
-    /**
-     * Returns a more detailed representation of this number's type. If this is finite, it will just return "number",
-     * otherwise it returns whether it is infinite or NaN.
-     *
-     * @param value The value to extract the type for.
-     * @return This value's numeric type.
-     */
-    @Nonnull
-    public static String getNumericType( double value )
-    {
-        if( Double.isNaN( value ) ) return "nan";
-        if( value == Double.POSITIVE_INFINITY ) return "inf";
-        if( value == Double.NEGATIVE_INFINITY ) return "-inf";
-        return "number";
-    }
-}

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

@@ -0,0 +1,407 @@
+/*
+ * This file is part of the public ComputerCraft API - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2020. 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 javax.annotation.Nullable;
+import java.nio.ByteBuffer;
+import java.util.Map;
+import java.util.Optional;
+
+import static dan200.computercraft.api.lua.LuaValues.checkFinite;
+
+/**
+ * The arguments passed to a function.
+ */
+public interface IArguments
+{
+    /**
+     * Get the number of arguments passed to this function.
+     *
+     * @return The number of passed arguments.
+     */
+    int count();
+
+    /**
+     * Get the argument at the specific index. The returned value must obey the following conversion rules:
+     *
+     * <ul>
+     *   <li>Lua values of type "string" will be represented by a {@link String}.</li>
+     *   <li>Lua values of type "number" will be represented by a {@link Number}.</li>
+     *   <li>Lua values of type "boolean" will be represented by a {@link Boolean}.</li>
+     *   <li>Lua values of type "table" will be represented by a {@link Map}.</li>
+     *   <li>Lua values of any other type will be represented by a {@code null} value.</li>
+     * </ul>
+     *
+     * @param index The argument number.
+     * @return The argument's value, or {@code null} if not present.
+     */
+    @Nullable
+    Object get( int index );
+
+    /**
+     * Drop a number of arguments. The returned arguments instance will access arguments at position {@code i + count},
+     * rather than {@code i}. However, errors will still use the given argument index.
+     *
+     * @param count The number of arguments to drop.
+     * @return The new {@link IArguments} instance.
+     */
+    IArguments drop( int count );
+
+    default Object[] getAll()
+    {
+        Object[] result = new Object[count()];
+        for( int i = 0; i < result.length; i++ ) result[i] = get( i );
+        return result;
+    }
+
+    /**
+     * Get an argument as a double.
+     *
+     * @param index The argument number.
+     * @return The argument's value.
+     * @throws LuaException If the value is not a number.
+     * @see #getFiniteDouble(int) if you require this to be finite (i.e. not infinite or NaN).
+     */
+    default double getDouble( int index ) throws LuaException
+    {
+        Object value = get( index );
+        if( !(value instanceof Number) ) throw LuaValues.badArgumentOf( index, "number", value );
+        return ((Number) value).doubleValue();
+    }
+
+    /**
+     * Get an argument as an integer.
+     *
+     * @param index The argument number.
+     * @return The argument's value.
+     * @throws LuaException If the value is not an integer.
+     */
+    default int getInt( int index ) throws LuaException
+    {
+        return (int) getLong( index );
+    }
+
+    /**
+     * Get an argument as a long.
+     *
+     * @param index The argument number.
+     * @return The argument's value.
+     * @throws LuaException If the value is not a long.
+     */
+    default long getLong( int index ) throws LuaException
+    {
+        Object value = get( index );
+        if( !(value instanceof Number) ) throw LuaValues.badArgumentOf( index, "number", value );
+        return LuaValues.checkFiniteNum( index, (Number) value ).longValue();
+    }
+
+    /**
+     * Get an argument as a finite number (not infinite or NaN).
+     *
+     * @param index The argument number.
+     * @return The argument's value.
+     * @throws LuaException If the value is not finite.
+     */
+    default double getFiniteDouble( int index ) throws LuaException
+    {
+        return checkFinite( index, getDouble( index ) );
+    }
+
+    /**
+     * Get an argument as a boolean.
+     *
+     * @param index The argument number.
+     * @return The argument's value.
+     * @throws LuaException If the value is not a boolean.
+     */
+    default boolean getBoolean( int index ) throws LuaException
+    {
+        Object value = get( index );
+        if( !(value instanceof Boolean) ) throw LuaValues.badArgumentOf( index, "boolean", value );
+        return (Boolean) value;
+    }
+
+    /**
+     * Get an argument as a string.
+     *
+     * @param index The argument number.
+     * @return The argument's value.
+     * @throws LuaException If the value is not a string.
+     */
+    @Nonnull
+    default String getString( int index ) throws LuaException
+    {
+        Object value = get( index );
+        if( !(value instanceof String) ) throw LuaValues.badArgumentOf( index, "string", value );
+        return (String) value;
+    }
+
+    /**
+     * Get a string argument as a byte array.
+     *
+     * @param index The argument number.
+     * @return The argument's value. This is a <em>read only</em> buffer.
+     * @throws LuaException If the value is not a string.
+     */
+    @Nonnull
+    default ByteBuffer getBytes( int index ) throws LuaException
+    {
+        return LuaValues.encode( getString( index ) );
+    }
+
+    /**
+     * Get a string argument as an enum value.
+     *
+     * @param index The argument number.
+     * @param klass The type of enum to parse.
+     * @param <T>   The type of enum to parse.
+     * @return The argument's value.
+     * @throws LuaException If the value is not a string or not a valid option for this enum.
+     */
+    @Nonnull
+    default <T extends Enum<T>> T getEnum( int index, Class<T> klass ) throws LuaException
+    {
+        return LuaValues.checkEnum( index, klass, getString( index ) );
+    }
+
+    /**
+     * Get an argument as a table.
+     *
+     * @param index The argument number.
+     * @return The argument's value.
+     * @throws LuaException If the value is not a table.
+     */
+    @Nonnull
+    default Map<?, ?> getTable( int index ) throws LuaException
+    {
+        Object value = get( index );
+        if( !(value instanceof Map) ) throw LuaValues.badArgumentOf( index, "table", value );
+        return (Map<?, ?>) value;
+    }
+
+    /**
+     * Get an argument as a double.
+     *
+     * @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 number.
+     */
+    @Nonnull
+    default Optional<Double> optDouble( int index ) throws LuaException
+    {
+        Object value = get( index );
+        if( value == null ) return Optional.empty();
+        if( !(value instanceof Number) ) throw LuaValues.badArgumentOf( index, "number", value );
+        return Optional.of( ((Number) value).doubleValue() );
+    }
+
+    /**
+     * Get an argument as an int.
+     *
+     * @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 number.
+     */
+    @Nonnull
+    default Optional<Integer> optInt( int index ) throws LuaException
+    {
+        return optLong( index ).map( Long::intValue );
+    }
+
+    /**
+     * Get an argument as a long.
+     *
+     * @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 number.
+     */
+    default Optional<Long> optLong( int index ) throws LuaException
+    {
+        Object value = get( index );
+        if( value == null ) return Optional.empty();
+        if( !(value instanceof Number) ) throw LuaValues.badArgumentOf( index, "number", value );
+        return Optional.of( LuaValues.checkFiniteNum( index, (Number) value ).longValue() );
+    }
+
+    /**
+     * Get an argument as a finite number (not infinite or NaN).
+     *
+     * @param index The argument number.
+     * @return The argument's value, or {@link Optional#empty()} if not present.
+     * @throws LuaException If the value is not finite.
+     */
+    default Optional<Double> optFiniteDouble( int index ) throws LuaException
+    {
+        Optional<Double> value = optDouble( index );
+        if( value.isPresent() ) LuaValues.checkFiniteNum( index, value.get() );
+        return value;
+    }
+
+    /**
+     * Get an argument as a boolean.
+     *
+     * @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 boolean.
+     */
+    default Optional<Boolean> optBoolean( int index ) throws LuaException
+    {
+        Object value = get( index );
+        if( value == null ) return Optional.empty();
+        if( !(value instanceof Boolean) ) throw LuaValues.badArgumentOf( index, "boolean", value );
+        return Optional.of( (Boolean) value );
+    }
+
+    /**
+     * Get an argument as a string.
+     *
+     * @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 string.
+     */
+    default Optional<String> optString( int index ) throws LuaException
+    {
+        Object value = get( index );
+        if( value == null ) return Optional.empty();
+        if( !(value instanceof String) ) throw LuaValues.badArgumentOf( index, "string", value );
+        return Optional.of( (String) value );
+    }
+
+    /**
+     * Get a string argument as a byte array.
+     *
+     * @param index The argument number.
+     * @return The argument's value, or {@link Optional#empty()} if not present. This is a <em>read only</em> buffer.
+     * @throws LuaException If the value is not a string.
+     */
+    default Optional<ByteBuffer> optBytes( int index ) throws LuaException
+    {
+        return optString( index ).map( LuaValues::encode );
+    }
+
+    /**
+     * Get a string argument as an enum value.
+     *
+     * @param index The argument number.
+     * @param klass The type of enum to parse.
+     * @param <T>   The type of enum to parse.
+     * @return The argument's value.
+     * @throws LuaException If the value is not a string or not a valid option for this enum.
+     */
+    @Nonnull
+    default <T extends Enum<T>> Optional<T> optEnum( int index, Class<T> klass ) throws LuaException
+    {
+        Optional<String> str = optString( index );
+        return str.isPresent() ? Optional.of( LuaValues.checkEnum( index, klass, str.get() ) ) : Optional.empty();
+    }
+
+    /**
+     * Get an argument as a table.
+     *
+     * @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.
+     */
+    default Optional<Map<?, ?>> optTable( 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( (Map<?, ?>) value );
+    }
+
+    /**
+     * Get an argument as a double.
+     *
+     * @param index The argument number.
+     * @param def   The default value, if this argument is not given.
+     * @return The argument's value, or {@code def} if none was provided.
+     * @throws LuaException If the value is not a number.
+     */
+    default double optDouble( int index, double def ) throws LuaException
+    {
+        return optDouble( index ).orElse( def );
+    }
+
+    /**
+     * Get an argument as an int.
+     *
+     * @param index The argument number.
+     * @param def   The default value, if this argument is not given.
+     * @return The argument's value, or {@code def} if none was provided.
+     * @throws LuaException If the value is not a number.
+     */
+    default int optInt( int index, int def ) throws LuaException
+    {
+        return optInt( index ).orElse( def );
+    }
+
+    /**
+     * Get an argument as a long.
+     *
+     * @param index The argument number.
+     * @param def   The default value, if this argument is not given.
+     * @return The argument's value, or {@code def} if none was provided.
+     * @throws LuaException If the value is not a number.
+     */
+    default long optLong( int index, long def ) throws LuaException
+    {
+        return optLong( index ).orElse( def );
+    }
+
+    /**
+     * Get an argument as a finite number (not infinite or NaN).
+     *
+     * @param index The argument number.
+     * @param def   The default value, if this argument is not given.
+     * @return The argument's value, or {@code def} if none was provided.
+     * @throws LuaException If the value is not finite.
+     */
+    default double optFiniteDouble( int index, double def ) throws LuaException
+    {
+        return optFiniteDouble( index ).orElse( def );
+    }
+
+    /**
+     * Get an argument as a boolean.
+     *
+     * @param index The argument number.
+     * @param def   The default value, if this argument is not given.
+     * @return The argument's value, or {@code def} if none was provided.
+     * @throws LuaException If the value is not a boolean.
+     */
+    default boolean optBoolean( int index, boolean def ) throws LuaException
+    {
+        return optBoolean( index ).orElse( def );
+    }
+
+    /**
+     * Get an argument as a string.
+     *
+     * @param index The argument number.
+     * @param def   The default value, if this argument is not given.
+     * @return The argument's value, or {@code def} if none was provided.
+     * @throws LuaException If the value is not a string.
+     */
+    default String optString( int index, String def ) throws LuaException
+    {
+        return optString( index ).orElse( def );
+    }
+
+    /**
+     * Get an argument as a table.
+     *
+     * @param index The argument number.
+     * @param def   The default value, if this argument is not given.
+     * @return The argument's value, or {@code def} if none was provided.
+     * @throws LuaException If the value is not a table.
+     */
+    default Map<?, ?> optTable( int index, Map<Object, Object> def ) throws LuaException
+    {
+        return optTable( index ).orElse( def );
+    }
+}

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

@@ -0,0 +1,45 @@
+/*
+ * This file is part of the public ComputerCraft API - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2020. 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 dan200.computercraft.api.peripheral.IDynamicPeripheral;
+
+import javax.annotation.Nonnull;
+
+/**
+ * An interface for representing custom objects returned by peripherals or other Lua objects.
+ *
+ * Generally, one does not need to implement this type - it is sufficient to return an object with some methods
+ * annotated with {@link LuaFunction}. {@link IDynamicLuaObject} is useful when you wish your available methods to
+ * change at runtime.
+ */
+public interface IDynamicLuaObject
+{
+    /**
+     * Get the names of the methods that this object implements. This should not change over the course of the object's
+     * lifetime.
+     *
+     * @return The method names this object provides.
+     * @see IDynamicPeripheral#getMethodNames()
+     */
+    @Nonnull
+    String[] getMethodNames();
+
+    /**
+     * Called when a user calls one of the methods that this object implements.
+     *
+     * @param context   The context of the currently running lua thread. This can be used to wait for events
+     *                  or otherwise yield.
+     * @param method    An integer identifying which method index from {@link #getMethodNames()} the computer wishes
+     *                  to call.
+     * @param arguments The arguments for this method.
+     * @return The result of this function. Either an immediate value ({@link MethodResult#of(Object...)} or an
+     * instruction to yield.
+     * @throws LuaException If the function threw an exception.
+     */
+    @Nonnull
+    MethodResult callMethod( @Nonnull ILuaContext context, int method, @Nonnull IArguments arguments ) throws LuaException;
+}

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

@@ -8,7 +8,8 @@ package dan200.computercraft.api.lua;
 import dan200.computercraft.api.ComputerCraftAPI;
 
 /**
- * Represents a {@link ILuaObject} which is stored as a global variable on computer startup.
+ * Represents a Lua object which is stored as a global variable on computer startup. This must either provide
+ * {@link LuaFunction} annotated functions or implement {@link IDynamicLuaObject}.
  *
  * Before implementing this interface, consider alternative methods of providing methods. It is generally preferred
  * to use peripherals to provide functionality to users.
@@ -16,7 +17,7 @@ import dan200.computercraft.api.ComputerCraftAPI;
  * @see ILuaAPIFactory
  * @see ComputerCraftAPI#registerAPIFactory(ILuaAPIFactory)
  */
-public interface ILuaAPI extends ILuaObject
+public interface ILuaAPI
 {
     /**
      * Get the globals this API will be assigned to. This will override any other global, so you should

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

@@ -0,0 +1,27 @@
+/*
+ * This file is part of the public ComputerCraft API - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2020. 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;
+
+/**
+ * A continuation which is called when this coroutine is resumed.
+ *
+ * @see MethodResult#yield(Object[], ILuaCallback)
+ */
+public interface ILuaCallback
+{
+    /**
+     * Resume this coroutine.
+     *
+     * @param args The result of resuming this coroutine. These will have the same form as described in
+     *             {@link LuaFunction}.
+     * @return The result of this continuation. Either the result to return to the callee, or another yield.
+     * @throws LuaException On an error.
+     */
+    @Nonnull
+    MethodResult resume( Object[] args ) throws LuaException;
+}

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

@@ -6,99 +6,25 @@
 package dan200.computercraft.api.lua;
 
 import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
 
 /**
- * An interface passed to peripherals and {@link ILuaObject}s by computers or turtles, providing methods
- * that allow the peripheral call to wait for events before returning, just like in lua. This is very useful if you need
- * to signal work to be performed on the main thread, and don't want to return until the work has been completed.
+ * An interface passed to peripherals and {@link IDynamicLuaObject}s by computers or turtles, providing methods
+ * that allow the peripheral call to interface with the computer.
  */
 public interface ILuaContext
 {
-    /**
-     * Wait for an event to occur on the computer, suspending the thread until it arises. This method is exactly
-     * equivalent to {@code os.pullEvent()} in lua.
-     *
-     * @param filter A specific event to wait for, or null to wait for any event.
-     * @return An object array containing the name of the event that occurred, and any event parameters.
-     * @throws LuaException         If the user presses CTRL+T to terminate the current program while pullEvent() is
-     *                              waiting for an event, a "Terminated" exception will be thrown here.
-     *
-     *                              Do not attempt to catch this exception. You should use {@link #pullEventRaw(String)}
-     *                              should you wish to disable termination.
-     * @throws InterruptedException If the user shuts down or reboots the computer while pullEvent() is waiting for an
-     *                              event, InterruptedException will be thrown. This exception must not be caught or
-     *                              intercepted, or the computer will leak memory and end up in a broken state.
-     */
-    @Nonnull
-    default Object[] pullEvent( @Nullable String filter ) throws LuaException, InterruptedException
-    {
-        Object[] results = pullEventRaw( filter );
-        if( results.length >= 1 && results[0].equals( "terminate" ) ) throw new LuaException( "Terminated", 0 );
-        return results;
-    }
-
-    /**
-     * The same as {@link #pullEvent(String)}, except "terminated" events are ignored. Only use this if you want to
-     * prevent program termination, which is not recommended. This method is exactly equivalent to
-     * {@code os.pullEventRaw()} in lua.
-     *
-     * @param filter A specific event to wait for, or null to wait for any event.
-     * @return An object array containing the name of the event that occurred, and any event parameters.
-     * @throws InterruptedException If the user shuts down or reboots the computer while pullEventRaw() is waiting for
-     *                              an event, InterruptedException will be thrown. This exception must not be caught or
-     *                              intercepted, or the computer will leak memory and end up in a broken state.
-     * @see #pullEvent(String)
-     */
-    @Nonnull
-    default Object[] pullEventRaw( @Nullable String filter ) throws InterruptedException
-    {
-        return yield( new Object[] { filter } );
-    }
-
-    /**
-     * Yield the current coroutine with some arguments until it is resumed. This method is exactly equivalent to
-     * {@code coroutine.yield()} in lua. Use {@code pullEvent()} if you wish to wait for events.
-     *
-     * @param arguments An object array containing the arguments to pass to coroutine.yield()
-     * @return An object array containing the return values from coroutine.yield()
-     * @throws InterruptedException If the user shuts down or reboots the computer the coroutine is suspended,
-     *                              InterruptedException will be thrown. This exception must not be caught or
-     *                              intercepted, or the computer will leak memory and end up in a broken state.
-     * @see #pullEvent(String)
-     */
-    @Nonnull
-    Object[] yield( @Nullable Object[] arguments ) throws InterruptedException;
-
-    /**
-     * Queue a task to be executed on the main server thread at the beginning of next tick, waiting for it to complete.
-     * This should be used when you need to interact with the world in a thread-safe manner.
-     *
-     * Note that the return values of your task are handled as events, meaning more complex objects such as maps or
-     * {@link ILuaObject} will not preserve their identities.
-     *
-     * @param task The task to execute on the main thread.
-     * @return The objects returned by {@code task}.
-     * @throws LuaException         If the task could not be queued, or if the task threw an exception.
-     * @throws InterruptedException If the user shuts down or reboots the computer the coroutine is suspended,
-     *                              InterruptedException will be thrown. This exception must not be caught or
-     *                              intercepted, or the computer will leak memory and end up in a broken state.
-     */
-    @Nullable
-    Object[] executeMainThreadTask( @Nonnull ILuaTask task ) throws LuaException, InterruptedException;
-
     /**
      * Queue a task to be executed on the main server thread at the beginning of next tick, but do not wait for it to
      * complete. This should be used when you need to interact with the world in a thread-safe manner but do not care
      * about the result or you wish to run asynchronously.
      *
      * When the task has finished, it will enqueue a {@code task_completed} event, which takes the task id, a success
-     * value and the return values, or an error message if it failed. If you need to wait on this event, it may be
-     * better to use {@link #executeMainThreadTask(ILuaTask)}.
+     * value and the return values, or an error message if it failed.
      *
      * @param task The task to execute on the main thread.
      * @return The "id" of the task. This will be the first argument to the {@code task_completed} event.
      * @throws LuaException If the task could not be queued.
+     * @see LuaFunction#mainThread() To run functions on the main thread and return their results synchronously.
      */
     long issueMainThreadTask( @Nonnull ILuaTask task ) throws LuaException;
 }

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

@@ -0,0 +1,29 @@
+/*
+ * This file is part of the public ComputerCraft API - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2020. 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;
+
+/**
+ * A function, which can be called from Lua. If you need to return a table of functions, it is recommended to use
+ * an object with {@link LuaFunction} methods, or implement {@link IDynamicLuaObject}.
+ *
+ * @see MethodResult#of(Object)
+ */
+@FunctionalInterface
+public interface ILuaFunction
+{
+    /**
+     * Call this function with a series of arguments. Note, this will <em>always</em> be called on the computer thread,
+     * and so its implementation must be thread-safe.
+     *
+     * @param arguments The arguments for this function
+     * @return The result of calling this function.
+     * @throws LuaException Upon Lua errors.
+     */
+    @Nonnull
+    MethodResult call( @Nonnull IArguments arguments ) throws LuaException;
+}

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

@@ -1,55 +0,0 @@
-/*
- * This file is part of the public ComputerCraft API - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2020. 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 dan200.computercraft.api.peripheral.IComputerAccess;
-import dan200.computercraft.api.peripheral.IPeripheral;
-
-import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
-
-/**
- * An interface for representing custom objects returned by {@link IPeripheral#callMethod(IComputerAccess, ILuaContext, int, Object[])}
- * calls.
- *
- * Return objects implementing this interface to expose objects with methods to lua.
- */
-public interface ILuaObject
-{
-    /**
-     * Get the names of the methods that this object implements. This works the same as {@link IPeripheral#getMethodNames()}.
-     * See that method for detailed documentation.
-     *
-     * @return The method names this object provides.
-     * @see IPeripheral#getMethodNames()
-     */
-    @Nonnull
-    String[] getMethodNames();
-
-    /**
-     * Called when a user calls one of the methods that this object implements. This works the same as
-     * {@link IPeripheral#callMethod(IComputerAccess, ILuaContext, int, Object[])}}. See that method for detailed
-     * documentation.
-     *
-     * @param context   The context of the currently running lua thread. This can be used to wait for events
-     *                  or otherwise yield.
-     * @param method    An integer identifying which of the methods from getMethodNames() the computercraft
-     *                  wishes to call. The integer indicates the index into the getMethodNames() table
-     *                  that corresponds to the string passed into peripheral.call()
-     * @param arguments The arguments for this method. See {@link IPeripheral#callMethod(IComputerAccess, ILuaContext, int, Object[])}
-     *                  the possible values and conversion rules.
-     * @return An array of objects, representing the values you wish to return to the Lua program.
-     * See {@link IPeripheral#callMethod(IComputerAccess, ILuaContext, int, Object[])} for the valid values and
-     * conversion rules.
-     * @throws LuaException         If the task could not be queued, or if the task threw an exception.
-     * @throws InterruptedException If the user shuts down or reboots the computer the coroutine is suspended,
-     *                              InterruptedException will be thrown. This exception must not be caught or
-     *                              intercepted, or the computer will leak memory and end up in a broken state.w
-     * @see IPeripheral#callMethod(IComputerAccess, ILuaContext, int, Object[])
-     */
-    @Nullable
-    Object[] callMethod( @Nonnull ILuaContext context, int method, @Nonnull Object[] arguments ) throws LuaException, InterruptedException;
-}

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

@@ -8,11 +8,10 @@ package dan200.computercraft.api.lua;
 import javax.annotation.Nullable;
 
 /**
- * A task which can be executed via {@link ILuaContext#executeMainThreadTask(ILuaTask)} or
- * {@link ILuaContext#issueMainThreadTask(ILuaTask)}. This will be run on the main thread, at the beginning of the
+ * A task which can be executed via {@link ILuaContext#issueMainThreadTask(ILuaTask)} This will be run on the main
+ * thread, at the beginning of the
  * next tick.
  *
- * @see ILuaContext#executeMainThreadTask(ILuaTask)
  * @see ILuaContext#issueMainThreadTask(ILuaTask)
  */
 @FunctionalInterface
@@ -21,8 +20,7 @@ public interface ILuaTask
     /**
      * Execute this task.
      *
-     * @return The arguments to add to the {@code task_completed} event. These will be returned by
-     * {@link ILuaContext#executeMainThreadTask(ILuaTask)}.
+     * @return The arguments to add to the {@code task_completed} event.
      * @throws LuaException If you throw any exception from this function, a lua error will be raised with the
      *                      same message as your exception. Use this to throw appropriate errors if the wrong
      *                      arguments are supplied to your method.

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

@@ -13,24 +13,33 @@ import javax.annotation.Nullable;
 public class LuaException extends Exception
 {
     private static final long serialVersionUID = -6136063076818512651L;
+    private final boolean hasLevel;
     private final int level;
 
-    public LuaException()
-    {
-        this( "error", 1 );
-    }
-
     public LuaException( @Nullable String message )
     {
-        this( message, 1 );
+        super( message );
+        this.hasLevel = false;
+        this.level = 1;
     }
 
     public LuaException( @Nullable String message, int level )
     {
         super( message );
+        this.hasLevel = true;
         this.level = level;
     }
 
+    /**
+     * Whether a level was explicitly specified when constructing. This is used to determine
+     *
+     * @return Whether this has an explicit level.
+     */
+    public boolean hasLevel()
+    {
+        return hasLevel;
+    }
+
     /**
      * The level this error is raised at. Level 1 is the function's caller, level 2 is that function's caller, and so
      * on.

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

@@ -0,0 +1,58 @@
+/*
+ * This file is part of the public ComputerCraft API - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2020. 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 dan200.computercraft.api.peripheral.IComputerAccess;
+import dan200.computercraft.api.peripheral.IPeripheral;
+
+import java.lang.annotation.*;
+import java.util.Map;
+import java.util.Optional;
+
+/**
+ * Used to mark a Java function which is callable from Lua.
+ *
+ * Methods annotated with {@link LuaFunction} must be public final instance methods. They can have any number of
+ * parameters, but they must be of the following types:
+ *
+ * <ul>
+ *   <li>{@link ILuaContext} (and {@link IComputerAccess} if on a {@link IPeripheral})</li>
+ *   <li>{@link IArguments}: The arguments supplied to this function.</li>
+ *   <li>
+ *     Alternatively, one may specify the desired arguments as normal parameters and the argument parsing code will
+ *     be generated automatically.
+ *
+ *     Each parameter must be one of the given types supported by {@link IArguments} (for instance, {@link int} or
+ *     {@link Map}). Optional values are supported by accepting a parameter of type {@link Optional}.
+ *   </li>
+ * </ul>
+ *
+ * This function may return {@link MethodResult}. However, if you simply return a value (rather than having to yield),
+ * you may return {@code void}, a single value (either an object or a primitive like {@code int}) or array of objects.
+ * These will be treated the same as {@link MethodResult#of()}, {@link MethodResult#of(Object)} and
+ * {@link MethodResult#of(Object...)}.
+ */
+@Documented
+@Retention( RetentionPolicy.RUNTIME )
+@Target( ElementType.METHOD )
+public @interface LuaFunction
+{
+    /**
+     * Explicitly specify the method names of this function. If not given, it uses the name of the annotated method.
+     *
+     * @return This function's name(s).
+     */
+    String[] value() default {};
+
+    /**
+     * 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
+     * @see ILuaContext#issueMainThreadTask(ILuaTask)
+     */
+    boolean mainThread() default false;
+}

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

@@ -0,0 +1,152 @@
+/*
+ * This file is part of the public ComputerCraft API - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2020. 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 javax.annotation.Nullable;
+import java.nio.ByteBuffer;
+import java.util.Map;
+
+/**
+ * Various utility functions for operating with Lua values.
+ *
+ * @see IArguments
+ */
+public final class LuaValues
+{
+    private LuaValues()
+    {
+    }
+
+    /**
+     * Encode a Lua string into a read-only {@link ByteBuffer}.
+     *
+     * @param string The string to encode.
+     * @return The encoded string.
+     */
+    @Nonnull
+    public static ByteBuffer encode( @Nonnull String string )
+    {
+        byte[] chars = new byte[string.length()];
+        for( int i = 0; i < chars.length; i++ )
+        {
+            char c = string.charAt( i );
+            chars[i] = c < 256 ? (byte) c : 63;
+        }
+
+        return ByteBuffer.wrap( chars ).asReadOnlyBuffer();
+    }
+
+    /**
+     * Returns a more detailed representation of this number's type. If this is finite, it will just return "number",
+     * otherwise it returns whether it is infinite or NaN.
+     *
+     * @param value The value to extract the type for.
+     * @return This value's numeric type.
+     */
+    @Nonnull
+    public static String getNumericType( double value )
+    {
+        if( Double.isNaN( value ) ) return "nan";
+        if( value == Double.POSITIVE_INFINITY ) return "inf";
+        if( value == Double.NEGATIVE_INFINITY ) return "-inf";
+        return "number";
+    }
+
+    /**
+     * Get a string representation of the given value's type.
+     *
+     * @param value The value whose type we are trying to compute.
+     * @return A string representation of the given value's type, in a similar format to that provided by Lua's
+     * {@code type} function.
+     */
+    @Nonnull
+    public static String getType( @Nullable Object value )
+    {
+        if( value == null ) return "nil";
+        if( value instanceof String ) return "string";
+        if( value instanceof Boolean ) return "boolean";
+        if( value instanceof Number ) return "number";
+        if( value instanceof Map ) return "table";
+        return "userdata";
+    }
+
+    /**
+     * Construct a "bad argument" exception, from an expected type and the actual value provided.
+     *
+     * @param index    The argument number, starting from 0.
+     * @param expected The expected type for this argument.
+     * @param actual   The actual value provided for this argument.
+     * @return The constructed exception, which should be thrown immediately.
+     */
+    @Nonnull
+    public static LuaException badArgumentOf( int index, @Nonnull String expected, @Nullable Object actual )
+    {
+        return badArgument( index, expected, getType( actual ) );
+    }
+
+    /**
+     * Construct a "bad argument" exception, from an expected and actual type.
+     *
+     * @param index    The argument number, starting from 0.
+     * @param expected The expected type for this argument.
+     * @param actual   The provided type for this argument.
+     * @return The constructed exception, which should be thrown immediately.
+     */
+    @Nonnull
+    public static LuaException badArgument( int index, @Nonnull String expected, @Nonnull String actual )
+    {
+        return new LuaException( "bad argument #" + (index + 1) + " (" + expected + " expected, got " + actual + ")" );
+    }
+
+    /**
+     * Ensure a numeric argument is finite (i.e. not infinite or {@link Double#NaN}.
+     *
+     * @param index The argument index to check.
+     * @param value The value to check.
+     * @return The input {@code value}.
+     * @throws LuaException If this is not a finite number.
+     */
+    public static Number checkFiniteNum( int index, Number value ) throws LuaException
+    {
+        checkFinite( index, value.doubleValue() );
+        return value;
+    }
+
+    /**
+     * Ensure a numeric argument is finite (i.e. not infinite or {@link Double#NaN}.
+     *
+     * @param index The argument index to check.
+     * @param value The value to check.
+     * @return The input {@code value}.
+     * @throws LuaException If this is not a finite number.
+     */
+    public static double checkFinite( int index, double value ) throws LuaException
+    {
+        if( !Double.isFinite( value ) ) throw badArgument( index, "number", getNumericType( value ) );
+        return value;
+    }
+
+    /**
+     * Ensure a string is a valid enum value.
+     *
+     * @param index The argument index to check.
+     * @param klass The class of the enum instance.
+     * @param value The value to extract.
+     * @param <T>   The type of enum we are extracting.
+     * @return The parsed enum value.
+     * @throws LuaException If this is not a known enum value.
+     */
+    public static <T extends Enum<T>> T checkEnum( int index, Class<T> klass, String value ) throws LuaException
+    {
+        for( T possibility : klass.getEnumConstants() )
+        {
+            if( possibility.name().equalsIgnoreCase( value ) ) return possibility;
+        }
+
+        throw new LuaException( "bad argument #" + (index + 1) + " (unknown option " + value + ")" );
+    }
+}

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

@@ -0,0 +1,170 @@
+/*
+ * This file is part of the public ComputerCraft API - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2020. 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 dan200.computercraft.api.peripheral.IComputerAccess;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+import java.nio.ByteBuffer;
+import java.util.Collection;
+import java.util.Map;
+import java.util.Objects;
+
+/**
+ * The result of invoking a Lua method.
+ *
+ * Method results either return a value immediately ({@link #of(Object...)} or yield control to the parent coroutine.
+ * When the current coroutine is resumed, we invoke the provided {@link ILuaCallback#resume(Object[])} callback.
+ */
+public final class MethodResult
+{
+    private static final MethodResult empty = new MethodResult( null, null );
+
+    private final Object[] result;
+    private final ILuaCallback callback;
+    private final int adjust;
+
+    private MethodResult( Object[] arguments, ILuaCallback callback )
+    {
+        this.result = arguments;
+        this.callback = callback;
+        this.adjust = 0;
+    }
+
+    private MethodResult( Object[] arguments, ILuaCallback callback, int adjust )
+    {
+        this.result = arguments;
+        this.callback = callback;
+        this.adjust = adjust;
+    }
+
+    /**
+     * Return no values immediately.
+     *
+     * @return A method result which returns immediately with no values.
+     */
+    @Nonnull
+    public static MethodResult of()
+    {
+        return empty;
+    }
+
+    /**
+     * Return a single value immediately.
+     *
+     * Integers, doubles, floats, strings, booleans, {@link Map}, {@link Collection}s, arrays and {@code null} will be
+     * converted to their corresponding Lua type. {@code byte[]} and {@link ByteBuffer} will be treated as binary
+     * strings. {@link ILuaFunction} will be treated as a function.
+     *
+     * In order to provide a custom object with methods, one may return a {@link IDynamicLuaObject}, or an arbitrary
+     * class with {@link LuaFunction} annotations. Anything else will be converted to {@code nil}.
+     *
+     * @param value The value to return to the calling Lua function.
+     * @return A method result which returns immediately with the given value.
+     */
+    @Nonnull
+    public static MethodResult of( @Nullable Object value )
+    {
+        return new MethodResult( new Object[] { value }, null );
+    }
+
+    /**
+     * Return any number of values immediately.
+     *
+     * @param values The values to return. See {@link #of(Object)} for acceptable values.
+     * @return A method result which returns immediately with the given values.
+     */
+    @Nonnull
+    public static MethodResult of( @Nullable Object... values )
+    {
+        return values == null || values.length == 0 ? empty : new MethodResult( values, null );
+    }
+
+    /**
+     * Wait for an event to occur on the computer, suspending the thread until it arises. This method is exactly
+     * equivalent to {@code os.pullEvent()} in lua.
+     *
+     * @param filter   A specific event to wait for, or null to wait for any event.
+     * @param callback The callback to resume with the name of the event that occurred, and any event parameters.
+     * @return The method result which represents this yield.
+     * @see IComputerAccess#queueEvent(String, Object[])
+     */
+    @Nonnull
+    public static MethodResult pullEvent( @Nullable String filter, @Nonnull ILuaCallback callback )
+    {
+        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 );
+            return callback.resume( results );
+        } );
+    }
+
+    /**
+     * The same as {@link #pullEvent(String, ILuaCallback)}, except "terminated" events are ignored. Only use this if
+     * you want to prevent program termination, which is not recommended. This method is exactly equivalent to
+     * {@code os.pullEventRaw()} in Lua.
+     *
+     * @param filter   A specific event to wait for, or null to wait for any event.
+     * @param callback The callback to resume with the name of the event that occurred, and any event parameters.
+     * @return The method result which represents this yield.
+     * @see #pullEvent(String, ILuaCallback)
+     */
+    @Nonnull
+    public static MethodResult pullEventRaw( @Nullable String filter, @Nonnull ILuaCallback callback )
+    {
+        Objects.requireNonNull( callback, "callback cannot be null" );
+        return new MethodResult( new Object[] { filter }, callback );
+    }
+
+    /**
+     * Yield the current coroutine with some arguments until it is resumed. This method is exactly equivalent to
+     * {@code coroutine.yield()} in lua. Use {@code pullEvent()} if you wish to wait for events.
+     *
+     * @param arguments An object array containing the arguments to pass to coroutine.yield()
+     * @param callback  The callback to resume with an array containing the return values from coroutine.yield()
+     * @return The method result which represents this yield.
+     * @see #pullEvent(String, ILuaCallback)
+     */
+    @Nonnull
+    public static MethodResult yield( @Nullable Object[] arguments, @Nonnull ILuaCallback callback )
+    {
+        Objects.requireNonNull( callback, "callback cannot be null" );
+        return new MethodResult( arguments, callback );
+    }
+
+    @Nullable
+    public Object[] getResult()
+    {
+        return result;
+    }
+
+    @Nullable
+    public ILuaCallback getCallback()
+    {
+        return callback;
+    }
+
+    public int getErrorAdjust()
+    {
+        return adjust;
+    }
+
+    /**
+     * Increase the Lua error by a specific amount. One should never need to use this function - it largely exists for
+     * some CC internal code.
+     *
+     * @param adjust The amount to increase the level by.
+     * @return The new {@link MethodResult} with an adjusted error. This has no effect on immediate results.
+     */
+    @Nonnull
+    public MethodResult adjustError( int adjust )
+    {
+        if( adjust < 0 ) throw new IllegalArgumentException( "cannot adjust by a negative amount" );
+        if( adjust == 0 || callback == null ) return this;
+        return new MethodResult( result, callback, this.adjust + adjust );
+    }
+}

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

@@ -0,0 +1,66 @@
+/*
+ * This file is part of the public ComputerCraft API - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2020. 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.Nullable;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Objects;
+
+/**
+ * An implementation of {@link IArguments} which wraps an array of {@link Object}.
+ */
+public final class ObjectArguments implements IArguments
+{
+    private static final IArguments EMPTY = new ObjectArguments();
+    private final List<Object> args;
+
+    @Deprecated
+    @SuppressWarnings( "unused" )
+    public ObjectArguments( IArguments arguments )
+    {
+        throw new IllegalStateException();
+    }
+
+    public ObjectArguments( Object... args )
+    {
+        this.args = Arrays.asList( args );
+    }
+
+    public ObjectArguments( List<Object> args )
+    {
+        this.args = Objects.requireNonNull( args );
+    }
+
+    @Override
+    public int count()
+    {
+        return args.size();
+    }
+
+    @Override
+    public IArguments drop( int count )
+    {
+        if( count < 0 ) throw new IllegalStateException( "count cannot be negative" );
+        if( count == 0 ) return this;
+        if( count >= args.size() ) return EMPTY;
+
+        return new ObjectArguments( args.subList( count, args.size() ) );
+    }
+
+    @Nullable
+    @Override
+    public Object get( int index )
+    {
+        return index >= args.size() ? null : args.get( index );
+    }
+
+    @Override
+    public Object[] getAll()
+    {
+        return args.toArray();
+    }
+}

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

@@ -79,7 +79,7 @@ public interface IMedia
      * @see IMount
      * @see dan200.computercraft.api.filesystem.IWritableMount
      * @see dan200.computercraft.api.ComputerCraftAPI#createSaveDirMount(World, String, long)
-     * @see dan200.computercraft.api.ComputerCraftAPI#createResourceMount(Class, String, String)
+     * @see dan200.computercraft.api.ComputerCraftAPI#createResourceMount(String, String)
      */
     @Nullable
     default IMount createDataMount( @Nonnull ItemStack stack, @Nonnull World world )

src/main/java/dan200/computercraft/api/network/IPacketReceiver.java

@@ -5,7 +5,7 @@
  */
 package dan200.computercraft.api.network;
 
-import net.minecraft.util.math.Vec3d;
+import net.minecraft.util.math.vector.Vector3d;
 import net.minecraft.world.World;
 
 import javax.annotation.Nonnull;
@@ -29,7 +29,7 @@ public interface IPacketReceiver
      * @return The receiver's position.
      */
     @Nonnull
-    Vec3d getPosition();
+    Vector3d getPosition();
 
     /**
      * Get the maximum distance this receiver can send and receive messages.

src/main/java/dan200/computercraft/api/network/IPacketSender.java

@@ -5,7 +5,7 @@
  */
 package dan200.computercraft.api.network;
 
-import net.minecraft.util.math.Vec3d;
+import net.minecraft.util.math.vector.Vector3d;
 import net.minecraft.world.World;
 
 import javax.annotation.Nonnull;
@@ -29,7 +29,7 @@ public interface IPacketSender
      * @return The sender's position.
      */
     @Nonnull
-    Vec3d getPosition();
+    Vector3d getPosition();
 
     /**
      * Get some sort of identification string for this sender. This does not strictly need to be unique, but you

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

@@ -8,13 +8,14 @@ package dan200.computercraft.api.peripheral;
 import dan200.computercraft.api.ComputerCraftAPI;
 import dan200.computercraft.api.filesystem.IMount;
 import dan200.computercraft.api.filesystem.IWritableMount;
+import dan200.computercraft.api.lua.ILuaCallback;
 import dan200.computercraft.api.lua.ILuaContext;
 import dan200.computercraft.api.lua.ILuaTask;
+import dan200.computercraft.api.lua.MethodResult;
 import net.minecraft.world.World;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
-import java.util.Collections;
 import java.util.Map;
 
 /**
@@ -31,9 +32,9 @@ public interface IComputerAccess
      * @param mount           The mount object to mount on the computer.
      * @return The location on the computer's file system where you the mount mounted, or {@code null} if there was already a
      * file in the desired location. Store this value if you wish to unmount the mount later.
-     * @throws RuntimeException If the peripheral has been detached.
+     * @throws NotAttachedException If the peripheral has been detached.
      * @see ComputerCraftAPI#createSaveDirMount(World, String, long)
-     * @see ComputerCraftAPI#createResourceMount(Class, String, String)
+     * @see ComputerCraftAPI#createResourceMount(String, String)
      * @see #mount(String, IMount, String)
      * @see #mountWritable(String, IWritableMount)
      * @see #unmount(String)
@@ -53,9 +54,9 @@ public interface IComputerAccess
      * @param driveName       A custom name to give for this mount location, as returned by {@code fs.getDrive()}.
      * @return The location on the computer's file system where you the mount mounted, or {@code null} if there was already a
      * file in the desired location. Store this value if you wish to unmount the mount later.
-     * @throws RuntimeException If the peripheral has been detached.
+     * @throws NotAttachedException If the peripheral has been detached.
      * @see ComputerCraftAPI#createSaveDirMount(World, String, long)
-     * @see ComputerCraftAPI#createResourceMount(Class, String, String)
+     * @see ComputerCraftAPI#createResourceMount(String, String)
      * @see #mount(String, IMount)
      * @see #mountWritable(String, IWritableMount)
      * @see #unmount(String)
@@ -71,9 +72,9 @@ public interface IComputerAccess
      * @param mount           The mount object to mount on the computer.
      * @return The location on the computer's file system where you the mount mounted, or null if there was already a
      * file in the desired location. Store this value if you wish to unmount the mount later.
-     * @throws RuntimeException If the peripheral has been detached.
+     * @throws NotAttachedException If the peripheral has been detached.
      * @see ComputerCraftAPI#createSaveDirMount(World, String, long)
-     * @see ComputerCraftAPI#createResourceMount(Class, String, String)
+     * @see ComputerCraftAPI#createResourceMount(String, String)
      * @see #mount(String, IMount)
      * @see #unmount(String)
      * @see IMount
@@ -92,9 +93,9 @@ public interface IComputerAccess
      * @param driveName       A custom name to give for this mount location, as returned by {@code fs.getDrive()}.
      * @return The location on the computer's file system where you the mount mounted, or null if there was already a
      * file in the desired location. Store this value if you wish to unmount the mount later.
-     * @throws RuntimeException If the peripheral has been detached.
+     * @throws NotAttachedException If the peripheral has been detached.
      * @see ComputerCraftAPI#createSaveDirMount(World, String, long)
-     * @see ComputerCraftAPI#createResourceMount(Class, String, String)
+     * @see ComputerCraftAPI#createResourceMount(String, String)
      * @see #mount(String, IMount)
      * @see #unmount(String)
      * @see IMount
@@ -114,8 +115,8 @@ public interface IComputerAccess
      * @param location The desired location in the computers file system of the directory to unmount.
      *                 This must be the location of a directory previously mounted by {@link #mount(String, IMount)} or
      *                 {@link #mountWritable(String, IWritableMount)}, as indicated by their return value.
-     * @throws RuntimeException If the peripheral has been detached.
-     * @throws RuntimeException If the mount does not exist, or was mounted by another peripheral.
+     * @throws NotAttachedException  If the peripheral has been detached.
+     * @throws IllegalStateException If the mount does not exist, or was mounted by another peripheral.
      * @see #mount(String, IMount)
      * @see #mountWritable(String, IWritableMount)
      */
@@ -146,10 +147,10 @@ public interface IComputerAccess
      *                  to lua data types in the same fashion as the return values of IPeripheral.callMethod().
      *
      *                  You may supply {@code null} to indicate that no arguments are to be supplied.
-     * @throws RuntimeException If the peripheral has been detached.
-     * @see IPeripheral#callMethod
+     * @throws NotAttachedException If the peripheral has been detached.
+     * @see MethodResult#pullEvent(String, ILuaCallback)
      */
-    void queueEvent( @Nonnull String event, @Nullable Object[] arguments );
+    void queueEvent( @Nonnull String event, @Nullable Object... arguments );
 
     /**
      * Get a string, unique to the computer, by which the computer refers to this peripheral.
@@ -159,7 +160,7 @@ public interface IComputerAccess
      * which peripheral the event came.
      *
      * @return A string unique to the computer, but not globally.
-     * @throws RuntimeException If the peripheral has been detached.
+     * @throws NotAttachedException If the peripheral has been detached.
      */
     @Nonnull
     String getAttachmentName();
@@ -170,14 +171,12 @@ public interface IComputerAccess
      * This may include other peripherals on the wired network or peripherals on other sides of the computer.
      *
      * @return All reachable peripherals
+     * @throws NotAttachedException If the peripheral has been detached.
      * @see #getAttachmentName()
      * @see #getAvailablePeripheral(String)
      */
     @Nonnull
-    default Map<String, IPeripheral> getAvailablePeripherals()
-    {
-        return Collections.emptyMap();
-    }
+    Map<String, IPeripheral> getAvailablePeripherals();
 
     /**
      * Get a reachable peripheral with the given attachment name. This is a equivalent to
@@ -188,10 +187,7 @@ public interface IComputerAccess
      * @see #getAvailablePeripherals()
      */
     @Nullable
-    default IPeripheral getAvailablePeripheral( @Nonnull String name )
-    {
-        return null;
-    }
+    IPeripheral getAvailablePeripheral( @Nonnull String name );
 
     /**
      * Get a {@link IWorkMonitor} for tasks your peripheral might execute on the main (server) thread.
@@ -205,10 +201,8 @@ public interface IComputerAccess
      * thread.
      *
      * @return The work monitor for the main thread, or {@code null} if this computer does not have one.
+     * @throws NotAttachedException If the peripheral has been detached.
      */
-    @Nullable
-    default IWorkMonitor getMainThreadMonitor()
-    {
-        return null;
-    }
+    @Nonnull
+    IWorkMonitor getMainThreadMonitor();
 }

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

@@ -0,0 +1,53 @@
+/*
+ * This file is part of the public ComputerCraft API - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2020. This API may be redistributed unmodified and in full only.
+ * For help using the API, and posting your mods, visit the forums at computercraft.info.
+ */
+package dan200.computercraft.api.peripheral;
+
+import dan200.computercraft.api.lua.*;
+
+import javax.annotation.Nonnull;
+
+/**
+ * A peripheral whose methods are not known at runtime.
+ *
+ * This behaves similarly to {@link IDynamicLuaObject}, though also accepting the current {@link IComputerAccess}.
+ * Generally one may use {@link LuaFunction} instead of implementing this interface.
+ */
+public interface IDynamicPeripheral extends IPeripheral
+{
+    /**
+     * Should return an array of strings that identify the methods that this peripheral exposes to Lua. This will be
+     * called once before each attachment, and should not change when called multiple times.
+     *
+     * @return An array of strings representing method names.
+     * @see #callMethod
+     */
+    @Nonnull
+    String[] getMethodNames();
+
+    /**
+     * This is called when a lua program on an attached computer calls {@code peripheral.call()} with
+     * one of the methods exposed by {@link #getMethodNames()}.
+     *
+     * Be aware that this will be called from the ComputerCraft Lua thread, and must be thread-safe when interacting
+     * with Minecraft objects.
+     *
+     * @param computer  The interface to the computer that is making the call. Remember that multiple
+     *                  computers can be attached to a peripheral at once.
+     * @param context   The context of the currently running lua thread. This can be used to wait for events
+     *                  or otherwise yield.
+     * @param method    An integer identifying which of the methods from getMethodNames() the computercraft
+     *                  wishes to call. The integer indicates the index into the getMethodNames() table
+     *                  that corresponds to the string passed into peripheral.call()
+     * @param arguments The arguments for this method.
+     * @return A {@link MethodResult} containing the values to return or the action to perform.
+     * @throws LuaException If you throw any exception from this function, a lua error will be raised with the
+     *                      same message as your exception. Use this to throw appropriate errors if the wrong
+     *                      arguments are supplied to your method.
+     * @see #getMethodNames()
+     */
+    @Nonnull
+    MethodResult callMethod( @Nonnull IComputerAccess computer, @Nonnull ILuaContext context, int method, @Nonnull IArguments arguments ) throws LuaException;
+}

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

@@ -5,15 +5,20 @@
  */
 package dan200.computercraft.api.peripheral;
 
-import dan200.computercraft.api.lua.ArgumentHelper;
-import dan200.computercraft.api.lua.ILuaContext;
-import dan200.computercraft.api.lua.LuaException;
+import dan200.computercraft.api.lua.LuaFunction;
+import net.minecraftforge.common.capabilities.Capability;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 
 /**
- * The interface that defines a peripheral. See {@link IPeripheralProvider} for how to associate blocks with peripherals.
+ * The interface that defines a peripheral.
+ *
+ * In order to expose a peripheral for your block or tile entity, you may either attach a {@link Capability}, or
+ * register a {@link IPeripheralProvider}. This <em>cannot</em> be implemented {@link IPeripheral} directly on the tile.
+ *
+ * Peripherals should provide a series of methods to the user, either using {@link LuaFunction} or by implementing
+ * {@link IDynamicPeripheral}.
  */
 public interface IPeripheral
 {
@@ -26,57 +31,6 @@ public interface IPeripheral
     @Nonnull
     String getType();
 
-    /**
-     * Should return an array of strings that identify the methods that this
-     * peripheral exposes to Lua. This will be called once before each attachment,
-     * and should not change when called multiple times.
-     *
-     * @return An array of strings representing method names.
-     * @see #callMethod
-     */
-    @Nonnull
-    String[] getMethodNames();
-
-    /**
-     * This is called when a lua program on an attached computer calls {@code peripheral.call()} with
-     * one of the methods exposed by {@link #getMethodNames()}.
-     *
-     * Be aware that this will be called from the ComputerCraft Lua thread, and must be thread-safe when interacting
-     * with Minecraft objects.
-     *
-     * @param computer  The interface to the computer that is making the call. Remember that multiple
-     *                  computers can be attached to a peripheral at once.
-     * @param context   The context of the currently running lua thread. This can be used to wait for events
-     *                  or otherwise yield.
-     * @param method    An integer identifying which of the methods from getMethodNames() the computercraft
-     *                  wishes to call. The integer indicates the index into the getMethodNames() table
-     *                  that corresponds to the string passed into peripheral.call()
-     * @param arguments An array of objects, representing the arguments passed into {@code peripheral.call()}.<br>
-     *                  Lua values of type "string" will be represented by Object type String.<br>
-     *                  Lua values of type "number" will be represented by Object type Double.<br>
-     *                  Lua values of type "boolean" will be represented by Object type Boolean.<br>
-     *                  Lua values of type "table" will be represented by Object type Map.<br>
-     *                  Lua values of any other type will be represented by a null object.<br>
-     *                  This array will be empty if no arguments are passed.
-     *
-     *                  It is recommended you use {@link ArgumentHelper} in order to validate and process arguments.
-     * @return An array of objects, representing values you wish to return to the lua program. Integers, Doubles, Floats,
-     * Strings, Booleans, Maps, ILuaObject and null be converted to their corresponding lua type. All other types will
-     * be converted to nil.
-     *
-     * You may return null to indicate no values should be returned.
-     * @throws LuaException         If you throw any exception from this function, a lua error will be raised with the
-     *                              same message as your exception. Use this to throw appropriate errors if the wrong
-     *                              arguments are supplied to your method.
-     * @throws InterruptedException If the user shuts down or reboots the computer the coroutine is suspended,
-     *                              InterruptedException will be thrown. This exception must not be caught or
-     *                              intercepted, or the computer will leak memory and end up in a broken state.
-     * @see #getMethodNames
-     * @see ArgumentHelper
-     */
-    @Nullable
-    Object[] callMethod( @Nonnull IComputerAccess computer, @Nonnull ILuaContext context, int method, @Nonnull Object[] arguments ) throws LuaException, InterruptedException;
-
     /**
      * Is called when when a computer is attaching to the peripheral.
      *
@@ -126,10 +80,10 @@ public interface IPeripheral
      *
      * @return The object this peripheral targets
      */
-    @Nonnull
+    @Nullable
     default Object getTarget()
     {
-        return this;
+        return null;
     }
 
     /**

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

@@ -9,14 +9,15 @@ import net.minecraft.tileentity.TileEntity;
 import net.minecraft.util.Direction;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.world.World;
+import net.minecraftforge.common.util.LazyOptional;
 
 import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
 
 /**
  * This interface is used to create peripheral implementations for blocks.
  *
- * If you have a {@link TileEntity} which acts as a peripheral, you may alternatively implement {@link IPeripheralTile}.
+ * If you have a {@link TileEntity} which acts as a peripheral, you may alternatively expose the {@link IPeripheral}
+ * capability.
  *
  * @see dan200.computercraft.api.ComputerCraftAPI#registerPeripheralProvider(IPeripheralProvider)
  */
@@ -29,9 +30,9 @@ public interface IPeripheralProvider
      * @param world The world the block is in.
      * @param pos   The position the block is at.
      * @param side  The side to get the peripheral from.
-     * @return A peripheral, or {@code null} if there is not a peripheral here you'd like to handle.
+     * @return A peripheral, or {@link LazyOptional#empty()} if there is not a peripheral here you'd like to handle.
      * @see dan200.computercraft.api.ComputerCraftAPI#registerPeripheralProvider(IPeripheralProvider)
      */
-    @Nullable
-    IPeripheral getPeripheral( @Nonnull World world, @Nonnull BlockPos pos, @Nonnull Direction side );
+    @Nonnull
+    LazyOptional<IPeripheral> getPeripheral( @Nonnull World world, @Nonnull BlockPos pos, @Nonnull Direction side );
 }

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

@@ -1,32 +0,0 @@
-/*
- * This file is part of the public ComputerCraft API - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2020. This API may be redistributed unmodified and in full only.
- * For help using the API, and posting your mods, visit the forums at computercraft.info.
- */
-package dan200.computercraft.api.peripheral;
-
-import net.minecraft.util.Direction;
-import net.minecraft.util.math.BlockPos;
-import net.minecraft.world.World;
-
-import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
-
-/**
- * A {@link net.minecraft.tileentity.TileEntity} which may act as a peripheral.
- *
- * If you need more complex capabilities (such as handling TEs not belonging to your mod), you should use
- * {@link IPeripheralProvider}.
- */
-public interface IPeripheralTile
-{
-    /**
-     * Get the peripheral on the given {@code side}.
-     *
-     * @param side The side to get the peripheral from.
-     * @return A peripheral, or {@code null} if there is not a peripheral here.
-     * @see IPeripheralProvider#getPeripheral(World, BlockPos, Direction)
-     */
-    @Nullable
-    IPeripheral getPeripheral( @Nonnull Direction side );
-}

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

@@ -0,0 +1,25 @@
+/*
+ * This file is part of the public ComputerCraft API - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2020. This API may be redistributed unmodified and in full only.
+ * For help using the API, and posting your mods, visit the forums at computercraft.info.
+ */
+package dan200.computercraft.api.peripheral;
+
+/**
+ * Thrown when performing operations on {@link IComputerAccess} when the current peripheral is no longer attached to
+ * the computer.
+ */
+public class NotAttachedException extends IllegalStateException
+{
+    private static final long serialVersionUID = 1221244785535553536L;
+
+    public NotAttachedException()
+    {
+        super( "You are not attached to this computer" );
+    }
+
+    public NotAttachedException( String s )
+    {
+        super( s );
+    }
+}

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

@@ -5,12 +5,15 @@
  */
 package dan200.computercraft.api.pocket;
 
+import net.minecraft.item.Item;
 import net.minecraft.item.ItemStack;
 import net.minecraft.util.IItemProvider;
 import net.minecraft.util.ResourceLocation;
 import net.minecraft.util.Util;
+import net.minecraftforge.common.util.NonNullSupplier;
 
 import javax.annotation.Nonnull;
+import java.util.function.Supplier;
 
 /**
  * A base class for {@link IPocketUpgrade}s.
@@ -21,23 +24,48 @@ public abstract class AbstractPocketUpgrade implements IPocketUpgrade
 {
     private final ResourceLocation id;
     private final String adjective;
-    private final ItemStack stack;
+    private final NonNullSupplier<ItemStack> stack;
 
-    protected AbstractPocketUpgrade( ResourceLocation id, String adjective, ItemStack stack )
+    protected AbstractPocketUpgrade( ResourceLocation id, String adjective, NonNullSupplier<ItemStack> stack )
     {
         this.id = id;
         this.adjective = adjective;
         this.stack = stack;
     }
 
+    protected AbstractPocketUpgrade( ResourceLocation id, NonNullSupplier<ItemStack> item )
+    {
+        this( id, Util.makeTranslationKey( "upgrade", id ) + ".adjective", item );
+    }
+
+    protected AbstractPocketUpgrade( ResourceLocation id, String adjective, ItemStack stack )
+    {
+        this( id, adjective, () -> stack );
+    }
+
+    protected AbstractPocketUpgrade( ResourceLocation id, ItemStack stack )
+    {
+        this( id, () -> stack );
+    }
+
     protected AbstractPocketUpgrade( ResourceLocation id, String adjective, IItemProvider item )
     {
-        this( id, adjective, new ItemStack( item ) );
+        this( id, adjective, new CachedStack( () -> item ) );
     }
 
     protected AbstractPocketUpgrade( ResourceLocation id, IItemProvider item )
     {
-        this( id, Util.makeTranslationKey( "upgrade", id ) + ".adjective", new ItemStack( item ) );
+        this( id, new CachedStack( () -> item ) );
+    }
+
+    protected AbstractPocketUpgrade( ResourceLocation id, String adjective, Supplier<? extends IItemProvider> item )
+    {
+        this( id, adjective, new CachedStack( item ) );
+    }
+
+    protected AbstractPocketUpgrade( ResourceLocation id, Supplier<? extends IItemProvider> item )
+    {
+        this( id, new CachedStack( item ) );
     }
 
     @Nonnull
@@ -58,6 +86,32 @@ public abstract class AbstractPocketUpgrade implements IPocketUpgrade
     @Override
     public final ItemStack getCraftingItem()
     {
-        return stack;
+        return stack.get();
+    }
+
+    /**
+     * Caches the construction of an item stack.
+     *
+     * @see dan200.computercraft.api.turtle.AbstractTurtleUpgrade For explanation of this class.
+     */
+    private static final class CachedStack implements NonNullSupplier<ItemStack>
+    {
+        private final Supplier<? extends IItemProvider> provider;
+        private Item item;
+        private ItemStack stack;
+
+        CachedStack( Supplier<? extends IItemProvider> 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 );
+        }
     }
 }

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

@@ -0,0 +1,126 @@
+/*
+ * This file is part of the public ComputerCraft API - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2020. 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 net.minecraft.item.Item;
+import net.minecraft.item.ItemStack;
+import net.minecraft.util.IItemProvider;
+import net.minecraft.util.ResourceLocation;
+import net.minecraft.util.Util;
+import net.minecraftforge.common.util.NonNullSupplier;
+
+import javax.annotation.Nonnull;
+import java.util.function.Supplier;
+
+/**
+ * A base class for {@link ITurtleUpgrade}s.
+ *
+ * One does not have to use this, but it does provide a convenient template.
+ */
+public abstract class AbstractTurtleUpgrade implements ITurtleUpgrade
+{
+    private final ResourceLocation id;
+    private final TurtleUpgradeType type;
+    private final String adjective;
+    private final NonNullSupplier<ItemStack> stack;
+
+    protected AbstractTurtleUpgrade( ResourceLocation id, TurtleUpgradeType type, String adjective, NonNullSupplier<ItemStack> stack )
+    {
+        this.id = id;
+        this.type = type;
+        this.adjective = adjective;
+        this.stack = stack;
+    }
+
+    protected AbstractTurtleUpgrade( ResourceLocation id, TurtleUpgradeType type, NonNullSupplier<ItemStack> stack )
+    {
+        this( id, type, Util.makeTranslationKey( "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, IItemProvider item )
+    {
+        this( id, type, adjective, new CachedStack( () -> item ) );
+    }
+
+    protected AbstractTurtleUpgrade( ResourceLocation id, TurtleUpgradeType type, IItemProvider item )
+    {
+        this( id, type, new CachedStack( () -> item ) );
+    }
+
+    protected AbstractTurtleUpgrade( ResourceLocation id, TurtleUpgradeType type, String adjective, Supplier<? extends IItemProvider> item )
+    {
+        this( id, type, adjective, new CachedStack( item ) );
+    }
+
+    protected AbstractTurtleUpgrade( ResourceLocation id, TurtleUpgradeType type, Supplier<? extends IItemProvider> item )
+    {
+        this( id, type, new CachedStack( item ) );
+    }
+
+    @Nonnull
+    @Override
+    public final ResourceLocation getUpgradeID()
+    {
+        return id;
+    }
+
+    @Nonnull
+    @Override
+    public final String getUnlocalisedAdjective()
+    {
+        return adjective;
+    }
+
+    @Nonnull
+    @Override
+    public final TurtleUpgradeType getType()
+    {
+        return type;
+    }
+
+    @Nonnull
+    @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 IItemProvider> provider;
+        private Item item;
+        private ItemStack stack;
+
+        CachedStack( Supplier<? extends IItemProvider> 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 );
+        }
+    }
+}

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

@@ -6,14 +6,14 @@
 package dan200.computercraft.api.turtle;
 
 import com.mojang.authlib.GameProfile;
-import dan200.computercraft.api.lua.ILuaContext;
-import dan200.computercraft.api.lua.LuaException;
+import dan200.computercraft.api.lua.ILuaCallback;
+import dan200.computercraft.api.lua.MethodResult;
 import dan200.computercraft.api.peripheral.IPeripheral;
 import net.minecraft.inventory.IInventory;
 import net.minecraft.nbt.CompoundNBT;
 import net.minecraft.util.Direction;
 import net.minecraft.util.math.BlockPos;
-import net.minecraft.util.math.Vec3d;
+import net.minecraft.util.math.vector.Vector3d;
 import net.minecraft.world.World;
 import net.minecraftforge.items.IItemHandlerModifiable;
 
@@ -67,7 +67,7 @@ public interface ITurtleAccess
      * @see #getVisualYaw(float)
      */
     @Nonnull
-    Vec3d getVisualPosition( float f );
+    Vector3d getVisualPosition( float f );
 
     /**
      * Returns the yaw the turtle is facing when it is rendered.
@@ -228,21 +228,15 @@ public interface ITurtleAccess
      * be supplied as a parameter to a "turtle_response" event issued to the turtle after the command has completed. Look at the
      * lua source code for "rom/apis/turtle" for how to build a lua wrapper around this functionality.
      *
-     * @param context The Lua context to pull events from.
      * @param command An object which will execute the custom command when its point in the queue is reached
      * @return The objects the command returned when executed. you should probably return these to the player
      * unchanged if called from a peripheral method.
      * @throws UnsupportedOperationException When attempting to execute a command on the client side.
-     * @throws LuaException                  If the user presses CTRL+T to terminate the current program while {@code executeCommand()} is
-     *                                       waiting for an event, a "Terminated" exception will be thrown here.
-     * @throws InterruptedException          If the user shuts down or reboots the computer while pullEvent() is waiting for an
-     *                                       event, InterruptedException will be thrown. This exception must not be caught or
-     *                                       intercepted, or the computer will leak memory and end up in a broken state.
      * @see ITurtleCommand
-     * @see ILuaContext#pullEvent(String)
+     * @see MethodResult#pullEvent(String, ILuaCallback)
      */
     @Nonnull
-    Object[] executeCommand( @Nonnull ILuaContext context, @Nonnull ITurtleCommand command ) throws LuaException, InterruptedException;
+    MethodResult executeCommand( @Nonnull ITurtleCommand command );
 
     /**
      * Start playing a specific animation. This will prevent other turtle commands from executing until

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

@@ -5,14 +5,12 @@
  */
 package dan200.computercraft.api.turtle;
 
-import dan200.computercraft.api.lua.ILuaContext;
-
 import javax.annotation.Nonnull;
 
 /**
- * An interface for objects executing custom turtle commands, used with {@link ITurtleAccess#executeCommand(ILuaContext, ITurtleCommand)}.
+ * An interface for objects executing custom turtle commands, used with {@link ITurtleAccess#executeCommand(ITurtleCommand)}.
  *
- * @see ITurtleAccess#executeCommand(ILuaContext, ITurtleCommand)
+ * @see ITurtleAccess#executeCommand(ITurtleCommand)
  */
 @FunctionalInterface
 public interface ITurtleCommand
@@ -25,7 +23,7 @@ public interface ITurtleCommand
      *
      * @param turtle Access to the turtle for whom the command was issued.
      * @return A result, indicating whether this action succeeded or not.
-     * @see ITurtleAccess#executeCommand(ILuaContext, ITurtleCommand)
+     * @see ITurtleAccess#executeCommand(ITurtleCommand)
      * @see TurtleCommandResult#success()
      * @see TurtleCommandResult#failure(String)
      * @see TurtleCommandResult

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

@@ -6,10 +6,10 @@
 package dan200.computercraft.api.turtle;
 
 import dan200.computercraft.api.ComputerCraftAPI;
+import dan200.computercraft.api.client.TransformedModel;
 import dan200.computercraft.api.peripheral.IPeripheral;
 import dan200.computercraft.api.turtle.event.TurtleAttackEvent;
 import dan200.computercraft.api.turtle.event.TurtleBlockEvent;
-import net.minecraft.client.renderer.model.IBakedModel;
 import net.minecraft.client.renderer.model.ModelResourceLocation;
 import net.minecraft.item.ItemStack;
 import net.minecraft.util.Direction;
@@ -18,11 +18,9 @@ import net.minecraftforge.api.distmarker.Dist;
 import net.minecraftforge.api.distmarker.OnlyIn;
 import net.minecraftforge.event.entity.player.AttackEntityEvent;
 import net.minecraftforge.event.world.BlockEvent;
-import org.apache.commons.lang3.tuple.Pair;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
-import javax.vecmath.Matrix4f;
 
 /**
  * The primary interface for defining an update for Turtles. A turtle update
@@ -126,12 +124,11 @@ public interface ITurtleUpgrade
      *
      * @param turtle Access to the turtle that the upgrade resides on. This will be null when getting item models!
      * @param side   Which side of the turtle (left or right) the upgrade resides on.
-     * @return The model that you wish to be used to render your upgrade, and a transformation to apply to it. Returning
-     * a transformation of {@code null} has the same effect as the identify matrix.
+     * @return The model that you wish to be used to render your upgrade.
      */
     @Nonnull
     @OnlyIn( Dist.CLIENT )
-    Pair<IBakedModel, Matrix4f> getModel( @Nullable ITurtleAccess turtle, @Nonnull TurtleSide side );
+    TransformedModel getModel( @Nullable ITurtleAccess turtle, @Nonnull TurtleSide side );
 
     /**
      * Called once per tick for each turtle which has the upgrade equipped.

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

@@ -17,70 +17,70 @@ public enum TurtleAnimation
     /**
      * An animation which does nothing. This takes no time to complete.
      *
-     * @see #Wait
-     * @see #ShortWait
+     * @see #WAIT
+     * @see #SHORT_WAIT
      */
-    None,
+    NONE,
 
     /**
      * Make the turtle move forward. Note that the animation starts from the block <em>behind</em> it, and
      * moves into this one.
      */
-    MoveForward,
+    MOVE_FORWARD,
 
     /**
      * Make the turtle move backwards. Note that the animation starts from the block <em>in front</em> it, and
      * moves into this one.
      */
-    MoveBack,
+    MOVE_BACK,
 
     /**
      * Make the turtle move backwards. Note that the animation starts from the block <em>above</em> it, and
      * moves into this one.
      */
-    MoveUp,
+    MOVE_UP,
 
     /**
      * Make the turtle move backwards. Note that the animation starts from the block <em>below</em> it, and
      * moves into this one.
      */
-    MoveDown,
+    MOVE_DOWN,
 
     /**
      * Turn the turtle to the left. Note that the animation starts with the turtle facing <em>right</em>, and
      * the turtle turns to face in the current direction.
      */
-    TurnLeft,
+    TURN_LEFT,
 
     /**
      * Turn the turtle to the left. Note that the animation starts with the turtle facing <em>right</em>, and
      * the turtle turns to face in the current direction.
      */
-    TurnRight,
+    TURN_RIGHT,
 
     /**
      * Swing the tool on the left.
      */
-    SwingLeftTool,
+    SWING_LEFT_TOOL,
 
     /**
      * Swing the tool on the right.
      */
-    SwingRightTool,
+    SWING_RIGHT_TOOL,
 
     /**
      * Wait until the animation has finished, performing no movement.
      *
-     * @see #ShortWait
-     * @see #None
+     * @see #SHORT_WAIT
+     * @see #NONE
      */
-    Wait,
+    WAIT,
 
     /**
      * Wait until the animation has finished, performing no movement. This takes 4 ticks to complete.
      *
-     * @see #Wait
-     * @see #None
+     * @see #WAIT
+     * @see #NONE
      */
-    ShortWait,
+    SHORT_WAIT,
 }

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

@@ -13,10 +13,10 @@ public enum TurtleSide
     /**
      * The turtle's left side (where the pickaxe usually is on a Wireless Mining Turtle).
      */
-    Left,
+    LEFT,
 
     /**
      * The turtle's right side (where the modem usually is on a Wireless Mining Turtle).
      */
-    Right,
+    RIGHT,
 }

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

@@ -16,28 +16,28 @@ public enum TurtleUpgradeType
      * A tool is rendered as an item on the side of the turtle, and responds to the {@code turtle.dig()}
      * and {@code turtle.attack()} methods (Such as pickaxe or sword on Mining and Melee turtles).
      */
-    Tool,
+    TOOL,
 
     /**
      * A peripheral adds a special peripheral which is attached to the side of the turtle,
      * and can be interacted with the {@code peripheral} API (Such as the modem on Wireless Turtles).
      */
-    Peripheral,
+    PERIPHERAL,
 
     /**
      * An upgrade which provides both a tool and a peripheral. This can be used when you wish
      * your upgrade to also provide methods. For example, a pickaxe could provide methods
      * determining whether it can break the given block or not.
      */
-    Both;
+    BOTH;
 
     public boolean isTool()
     {
-        return this == Tool || this == Both;
+        return this == TOOL || this == BOTH;
     }
 
     public boolean isPeripheral()
     {
-        return this == Peripheral || this == Both;
+        return this == PERIPHERAL || this == BOTH;
     }
 }

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

@@ -19,10 +19,10 @@ public enum TurtleVerb
     /**
      * The turtle called {@code turtle.dig()}, {@code turtle.digUp()} or {@code turtle.digDown()}.
      */
-    Dig,
+    DIG,
 
     /**
      * The turtle called {@code turtle.attack()}, {@code turtle.attackUp()} or {@code turtle.attackDown()}.
      */
-    Attack,
+    ATTACK,
 }

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

@@ -5,8 +5,7 @@
  */
 package dan200.computercraft.api.turtle.event;
 
-import dan200.computercraft.api.lua.ILuaContext;
-import dan200.computercraft.api.peripheral.IComputerAccess;
+import dan200.computercraft.api.lua.MethodResult;
 import dan200.computercraft.api.turtle.ITurtleAccess;
 import dan200.computercraft.api.turtle.ITurtleUpgrade;
 import dan200.computercraft.api.turtle.TurtleSide;
@@ -223,7 +222,7 @@ public abstract class TurtleBlockEvent extends TurtlePlayerEvent
          * Add new information to the inspection result. Note this will override fields with the same name.
          *
          * @param newData The data to add. Note all values should be convertible to Lua (see
-         *                {@link dan200.computercraft.api.peripheral.IPeripheral#callMethod(IComputerAccess, ILuaContext, int, Object[])}).
+         *                {@link MethodResult#of(Object)}).
          */
         public void addData( @Nonnull Map<String, ?> newData )
         {

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

@@ -5,8 +5,7 @@
  */
 package dan200.computercraft.api.turtle.event;
 
-import dan200.computercraft.api.lua.ILuaContext;
-import dan200.computercraft.api.peripheral.IComputerAccess;
+import dan200.computercraft.api.lua.MethodResult;
 import dan200.computercraft.api.turtle.ITurtleAccess;
 import net.minecraft.item.ItemStack;
 
@@ -17,8 +16,8 @@ import java.util.Objects;
 /**
  * Fired when a turtle gathers data on an item in its inventory.
  *
- * You may prevent items being inspected, or add additional information to the result. Be aware that this is fired on
- * the computer thread, and so any operations on it must be thread safe.
+ * You may prevent items being inspected, or add additional information to the result. Be aware that this may be fired
+ * on the computer thread, and so any operations on it must be thread safe.
  *
  * @see TurtleAction#INSPECT_ITEM
  */
@@ -26,8 +25,15 @@ public class TurtleInspectItemEvent extends TurtleActionEvent
 {
     private final ItemStack stack;
     private final Map<String, Object> data;
+    private final boolean mainThread;
 
+    @Deprecated
     public TurtleInspectItemEvent( @Nonnull ITurtleAccess turtle, @Nonnull ItemStack stack, @Nonnull Map<String, Object> data )
+    {
+        this( turtle, stack, data, false );
+    }
+
+    public TurtleInspectItemEvent( @Nonnull ITurtleAccess turtle, @Nonnull ItemStack stack, @Nonnull Map<String, Object> data, boolean mainThread )
     {
         super( turtle, TurtleAction.INSPECT_ITEM );
 
@@ -35,6 +41,7 @@ public class TurtleInspectItemEvent extends TurtleActionEvent
         Objects.requireNonNull( data, "data cannot be null" );
         this.stack = stack;
         this.data = data;
+        this.mainThread = mainThread;
     }
 
     /**
@@ -59,11 +66,22 @@ public class TurtleInspectItemEvent extends TurtleActionEvent
         return data;
     }
 
+    /**
+     * If this event is being fired on the server thread. When true, information which relies on server state may be
+     * exposed.
+     *
+     * @return If this is run on the main thread.
+     */
+    public boolean onMainThread()
+    {
+        return mainThread;
+    }
+
     /**
      * Add new information to the inspection result. Note this will override fields with the same name.
      *
      * @param newData The data to add. Note all values should be convertible to Lua (see
-     *                {@link dan200.computercraft.api.peripheral.IPeripheral#callMethod(IComputerAccess, ILuaContext, int, Object[])}).
+     *                {@link MethodResult#of(Object)}).
      */
     public void addData( @Nonnull Map<String, ?> newData )
     {

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

@@ -7,24 +7,25 @@ package dan200.computercraft.client;
 
 import dan200.computercraft.ComputerCraft;
 import dan200.computercraft.client.render.TurtleModelLoader;
+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;
 import dan200.computercraft.shared.pocket.items.ItemPocketComputer;
 import dan200.computercraft.shared.util.Colour;
-import net.minecraft.client.Minecraft;
 import net.minecraft.client.renderer.model.IBakedModel;
 import net.minecraft.client.renderer.model.IUnbakedModel;
 import net.minecraft.client.renderer.model.ModelResourceLocation;
-import net.minecraft.client.renderer.vertex.DefaultVertexFormats;
+import net.minecraft.inventory.container.PlayerContainer;
 import net.minecraft.util.ResourceLocation;
 import net.minecraftforge.api.distmarker.Dist;
 import net.minecraftforge.client.event.ColorHandlerEvent;
 import net.minecraftforge.client.event.ModelBakeEvent;
 import net.minecraftforge.client.event.ModelRegistryEvent;
 import net.minecraftforge.client.event.TextureStitchEvent;
-import net.minecraftforge.client.model.BasicState;
 import net.minecraftforge.client.model.ModelLoader;
 import net.minecraftforge.client.model.ModelLoaderRegistry;
+import net.minecraftforge.client.model.SimpleModelTransform;
 import net.minecraftforge.eventbus.api.SubscribeEvent;
 import net.minecraftforge.fml.common.Mod;
 
@@ -71,13 +72,13 @@ public final class ClientRegistry
     @SubscribeEvent
     public static void registerModels( ModelRegistryEvent event )
     {
-        ModelLoaderRegistry.registerLoader( TurtleModelLoader.INSTANCE );
+        ModelLoaderRegistry.registerLoader( new ResourceLocation( ComputerCraft.MOD_ID, "turtle" ), TurtleModelLoader.INSTANCE );
     }
 
     @SubscribeEvent
     public static void onTextureStitchEvent( TextureStitchEvent.Pre event )
     {
-        if( event.getMap() != Minecraft.getInstance().getTextureMap() ) return;
+        if( !event.getMap().getTextureLocation().equals( PlayerContainer.LOCATION_BLOCKS_TEXTURE ) ) return;
 
         for( String extra : EXTRA_TEXTURES )
         {
@@ -92,35 +93,24 @@ public final class ClientRegistry
         ModelLoader loader = event.getModelLoader();
         Map<ResourceLocation, IBakedModel> registry = event.getModelRegistry();
 
-        for( String model : EXTRA_MODELS )
+        for( String modelName : EXTRA_MODELS )
         {
-            IBakedModel bakedModel = bake( loader, loader.getUnbakedModel( new ResourceLocation( ComputerCraft.MOD_ID, "item/" + model ) ) );
+            ResourceLocation location = new ResourceLocation( ComputerCraft.MOD_ID, "item/" + modelName );
+            IUnbakedModel model = loader.getUnbakedModel( location );
+            model.getTextures( loader::getUnbakedModel, new HashSet<>() );
 
-            if( bakedModel != null )
+            IBakedModel baked = model.bakeModel( loader, ModelLoader.defaultTextureGetter(), SimpleModelTransform.IDENTITY, location );
+            if( baked != null )
             {
-                registry.put(
-                    new ModelResourceLocation( new ResourceLocation( ComputerCraft.MOD_ID, model ), "inventory" ),
-                    bakedModel
-                );
+                registry.put( new ModelResourceLocation( new ResourceLocation( ComputerCraft.MOD_ID, modelName ), "inventory" ), baked );
             }
         }
-
-        // And load the custom turtle models in too.
-        registry.put(
-            new ModelResourceLocation( new ResourceLocation( ComputerCraft.MOD_ID, "turtle_normal" ), "inventory" ),
-            bake( loader, TurtleModelLoader.INSTANCE.loadModel( new ResourceLocation( ComputerCraft.MOD_ID, "item/turtle_normal" ) ) )
-        );
-
-        registry.put(
-            new ModelResourceLocation( new ResourceLocation( ComputerCraft.MOD_ID, "turtle_advanced" ), "inventory" ),
-            bake( loader, TurtleModelLoader.INSTANCE.loadModel( new ResourceLocation( ComputerCraft.MOD_ID, "item/turtle_advanced" ) ) )
-        );
     }
 
     @SubscribeEvent
     public static void onItemColours( ColorHandlerEvent.Item event )
     {
-        if( ComputerCraft.Items.disk == null || ComputerCraft.Blocks.turtleNormal == null )
+        if( Registry.ModItems.DISK == null || Registry.ModBlocks.TURTLE_NORMAL == null )
         {
             ComputerCraft.log.warn( "Block/item registration has failed. Skipping registration of item colours." );
             return;
@@ -128,7 +118,12 @@ public final class ClientRegistry
 
         event.getItemColors().register(
             ( stack, layer ) -> layer == 1 ? ((ItemDisk) stack.getItem()).getColour( stack ) : 0xFFFFFF,
-            ComputerCraft.Items.disk
+            Registry.ModItems.DISK.get()
+        );
+
+        event.getItemColors().register(
+            ( stack, layer ) -> layer == 1 ? ItemTreasureDisk.getColour( stack ) : 0xFFFFFF,
+            Registry.ModItems.TREASURE_DISK.get()
         );
 
         event.getItemColors().register( ( stack, layer ) -> {
@@ -142,26 +137,15 @@ public final class ClientRegistry
                 case 2: // Light colour
                 {
                     int light = ItemPocketComputer.getLightState( stack );
-                    return light == -1 ? Colour.Black.getHex() : light;
+                    return light == -1 ? Colour.BLACK.getHex() : light;
                 }
             }
-        }, ComputerCraft.Items.pocketComputerNormal, ComputerCraft.Items.pocketComputerAdvanced );
+        }, Registry.ModItems.POCKET_COMPUTER_NORMAL.get(), Registry.ModItems.POCKET_COMPUTER_ADVANCED.get() );
 
         // Setup turtle colours
         event.getItemColors().register(
             ( stack, tintIndex ) -> tintIndex == 0 ? ((IColouredItem) stack.getItem()).getColour( stack ) : 0xFFFFFF,
-            ComputerCraft.Blocks.turtleNormal, ComputerCraft.Blocks.turtleAdvanced
-        );
-    }
-
-    private static IBakedModel bake( ModelLoader loader, IUnbakedModel model )
-    {
-        model.getTextures( loader::getUnbakedModel, new HashSet<>() );
-
-        return model.bake(
-            loader,
-            ModelLoader.defaultTextureGetter(),
-            new BasicState( model.getDefaultState(), false ), DefaultVertexFormats.BLOCK
+            Registry.ModBlocks.TURTLE_NORMAL.get(), Registry.ModBlocks.TURTLE_ADVANCED.get()
         );
     }
 }

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

@@ -12,14 +12,12 @@ import it.unimi.dsi.fastutil.ints.Int2IntOpenHashMap;
 import net.minecraft.client.Minecraft;
 import net.minecraft.client.gui.FontRenderer;
 import net.minecraft.client.gui.NewChatGui;
-import net.minecraft.client.gui.RenderComponentsUtil;
 import net.minecraft.util.math.MathHelper;
 import net.minecraft.util.text.ITextComponent;
 import net.minecraft.util.text.TextFormatting;
 import org.apache.commons.lang3.StringUtils;
 
 import javax.annotation.Nullable;
-import java.util.List;
 
 public class ClientTableFormatter implements TableFormatter
 {
@@ -57,7 +55,7 @@ public class ClientTableFormatter implements TableFormatter
     @Override
     public int getWidth( ITextComponent component )
     {
-        return renderer().getStringWidth( component.getFormattedText() );
+        return renderer().func_238414_a_( component );
     }
 
     @Override
@@ -66,10 +64,11 @@ public class ClientTableFormatter implements TableFormatter
         Minecraft mc = Minecraft.getInstance();
         NewChatGui chat = mc.ingameGUI.getChatGUI();
 
-        // Trim the text if it goes over the allowed length
-        int maxWidth = MathHelper.floor( chat.getChatWidth() / chat.getScale() );
-        List<ITextComponent> list = RenderComponentsUtil.splitText( component, maxWidth, mc.fontRenderer, false, false );
-        if( !list.isEmpty() ) chat.printChatMessageWithOptionalDeletion( list.get( 0 ), id );
+        // 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 );
+        // if( !list.isEmpty() ) chat.printChatMessageWithOptionalDeletion( list.get( 0 ), id );
+        chat.printChatMessageWithOptionalDeletion( component, id );
     }
 
     @Override

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

@@ -5,18 +5,22 @@
  */
 package dan200.computercraft.client.gui;
 
-import com.mojang.blaze3d.platform.GlStateManager;
+import com.mojang.blaze3d.systems.RenderSystem;
+import com.mojang.blaze3d.vertex.IVertexBuilder;
 import dan200.computercraft.client.FrameInfo;
 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.BufferBuilder;
-import net.minecraft.client.renderer.Tessellator;
+import net.minecraft.client.renderer.IRenderTypeBuffer;
+import net.minecraft.client.renderer.RenderState;
+import net.minecraft.client.renderer.RenderType;
 import net.minecraft.client.renderer.vertex.DefaultVertexFormats;
 import net.minecraft.client.renderer.vertex.VertexFormat;
 import net.minecraft.util.ResourceLocation;
+import net.minecraft.util.math.vector.Matrix4f;
+import net.minecraft.util.math.vector.TransformationMatrix;
 import org.lwjgl.opengl.GL11;
 
 import javax.annotation.Nonnull;
@@ -24,21 +28,10 @@ import javax.annotation.Nullable;
 
 public final class FixedWidthFontRenderer
 {
+    private static final Matrix4f IDENTITY = TransformationMatrix.identity().getMatrix();
+
     private static final ResourceLocation FONT = new ResourceLocation( "computercraft", "textures/gui/term_font.png" );
 
-    /**
-     * Like {@link DefaultVertexFormats#POSITION_TEX_COLOR}, but flipped. This is backported from 1.15, hence the
-     * custom format.
-     */
-    public static final VertexFormat POSITION_COLOR_TEX = new VertexFormat();
-
-    static
-    {
-        POSITION_COLOR_TEX.addElement( DefaultVertexFormats.POSITION_3F );
-        POSITION_COLOR_TEX.addElement( DefaultVertexFormats.COLOR_4UB );
-        POSITION_COLOR_TEX.addElement( DefaultVertexFormats.TEX_2F );
-    }
-
     public static final int FONT_HEIGHT = 9;
     public static final int FONT_WIDTH = 6;
     public static final float WIDTH = 256.0f;
@@ -46,22 +39,23 @@ public final class FixedWidthFontRenderer
     public static final float BACKGROUND_START = (WIDTH - 6.0f) / WIDTH;
     public static final float BACKGROUND_END = (WIDTH - 4.0f) / WIDTH;
 
+    public static final RenderType TYPE = Type.MAIN;
+
     private FixedWidthFontRenderer()
     {
     }
 
-    private static float toGreyscale( double[] rgb )
+    public static float toGreyscale( double[] rgb )
     {
         return (float) ((rgb[0] + rgb[1] + rgb[2]) / 3);
     }
 
-    private static int getColour( char c )
+    public static int getColour( char c, Colour def )
     {
-        int i = "0123456789abcdef".indexOf( c );
-        return i < 0 ? 0 : 15 - i;
+        return 15 - Terminal.getColour( c, def );
     }
 
-    private static void drawChar( BufferBuilder buffer, float x, float y, int index, float r, float g, float b )
+    private static void drawChar( Matrix4f transform, IVertexBuilder buffer, float x, float y, int index, float r, float g, float b )
     {
         // Short circuit to avoid the common case - the texture should be blank here after all.
         if( index == '\0' || index == ' ' ) return;
@@ -72,27 +66,27 @@ public final class FixedWidthFontRenderer
         int xStart = 1 + column * (FONT_WIDTH + 2);
         int yStart = 1 + row * (FONT_HEIGHT + 2);
 
-        buffer.pos( x, y, 0f ).color( r, g, b, 1.0f ).tex( xStart / WIDTH, yStart / WIDTH ).endVertex();
-        buffer.pos( x, y + FONT_HEIGHT, 0f ).color( r, g, b, 1.0f ).tex( xStart / WIDTH, (yStart + FONT_HEIGHT) / WIDTH ).endVertex();
-        buffer.pos( x + FONT_WIDTH, y, 0f ).color( r, g, b, 1.0f ).tex( (xStart + FONT_WIDTH) / WIDTH, yStart / WIDTH ).endVertex();
-        buffer.pos( x + FONT_WIDTH, y, 0f ).color( r, g, b, 1.0f ).tex( (xStart + FONT_WIDTH) / WIDTH, yStart / WIDTH ).endVertex();
-        buffer.pos( x, y + FONT_HEIGHT, 0f ).color( r, g, b, 1.0f ).tex( xStart / WIDTH, (yStart + FONT_HEIGHT) / WIDTH ).endVertex();
-        buffer.pos( x + FONT_WIDTH, y + FONT_HEIGHT, 0f ).color( r, g, b, 1.0f ).tex( (xStart + FONT_WIDTH) / WIDTH, (yStart + FONT_HEIGHT) / WIDTH ).endVertex();
+        buffer.pos( transform, x, y, 0f ).color( r, g, b, 1.0f ).tex( xStart / WIDTH, yStart / WIDTH ).endVertex();
+        buffer.pos( transform, x, y + FONT_HEIGHT, 0f ).color( r, g, b, 1.0f ).tex( xStart / WIDTH, (yStart + FONT_HEIGHT) / WIDTH ).endVertex();
+        buffer.pos( transform, x + FONT_WIDTH, y, 0f ).color( r, g, b, 1.0f ).tex( (xStart + FONT_WIDTH) / WIDTH, yStart / WIDTH ).endVertex();
+        buffer.pos( transform, x + FONT_WIDTH, y, 0f ).color( r, g, b, 1.0f ).tex( (xStart + FONT_WIDTH) / WIDTH, yStart / WIDTH ).endVertex();
+        buffer.pos( transform, x, y + FONT_HEIGHT, 0f ).color( r, g, b, 1.0f ).tex( xStart / WIDTH, (yStart + FONT_HEIGHT) / WIDTH ).endVertex();
+        buffer.pos( transform, x + FONT_WIDTH, y + FONT_HEIGHT, 0f ).color( r, g, b, 1.0f ).tex( (xStart + FONT_WIDTH) / WIDTH, (yStart + FONT_HEIGHT) / WIDTH ).endVertex();
     }
 
-    private static void drawQuad( BufferBuilder buffer, float x, float y, float width, float height, float r, float g, float b )
+    private static void drawQuad( Matrix4f transform, IVertexBuilder buffer, float x, float y, float width, float height, float r, float g, float b )
     {
-        buffer.pos( x, y, 0 ).color( r, g, b, 1.0f ).tex( BACKGROUND_START, BACKGROUND_START ).endVertex();
-        buffer.pos( x, y + height, 0 ).color( r, g, b, 1.0f ).tex( BACKGROUND_START, BACKGROUND_END ).endVertex();
-        buffer.pos( x + width, y, 0 ).color( r, g, b, 1.0f ).tex( BACKGROUND_END, BACKGROUND_START ).endVertex();
-        buffer.pos( x + width, y, 0 ).color( r, g, b, 1.0f ).tex( BACKGROUND_END, BACKGROUND_START ).endVertex();
-        buffer.pos( x, y + height, 0 ).color( r, g, b, 1.0f ).tex( BACKGROUND_START, BACKGROUND_END ).endVertex();
-        buffer.pos( x + width, y + height, 0 ).color( r, g, b, 1.0f ).tex( BACKGROUND_END, BACKGROUND_END ).endVertex();
+        buffer.pos( transform, x, y, 0 ).color( r, g, b, 1.0f ).tex( BACKGROUND_START, BACKGROUND_START ).endVertex();
+        buffer.pos( transform, x, y + height, 0 ).color( r, g, b, 1.0f ).tex( BACKGROUND_START, BACKGROUND_END ).endVertex();
+        buffer.pos( transform, x + width, y, 0 ).color( r, g, b, 1.0f ).tex( BACKGROUND_END, BACKGROUND_START ).endVertex();
+        buffer.pos( transform, x + width, y, 0 ).color( r, g, b, 1.0f ).tex( BACKGROUND_END, BACKGROUND_START ).endVertex();
+        buffer.pos( transform, x, y + height, 0 ).color( r, g, b, 1.0f ).tex( BACKGROUND_START, BACKGROUND_END ).endVertex();
+        buffer.pos( transform, x + width, y + height, 0 ).color( r, g, b, 1.0f ).tex( BACKGROUND_END, BACKGROUND_END ).endVertex();
     }
 
-    private static void drawQuad( BufferBuilder buffer, float x, float y, float width, float height, Palette palette, boolean greyscale, char colourIndex )
+    private static void drawQuad( Matrix4f transform, IVertexBuilder buffer, float x, float y, float width, float height, Palette palette, boolean greyscale, char colourIndex )
     {
-        double[] colour = palette.getColour( getColour( colourIndex ) );
+        double[] colour = palette.getColour( getColour( colourIndex, Colour.BLACK ) );
         float r, g, b;
         if( greyscale )
         {
@@ -105,23 +99,23 @@ public final class FixedWidthFontRenderer
             b = (float) colour[2];
         }
 
-        drawQuad( buffer, x, y, width, height, r, g, b );
+        drawQuad( transform, buffer, x, y, width, height, r, g, b );
     }
 
     private static void drawBackground(
-        @Nonnull BufferBuilder renderer, float x, float y,
+        @Nonnull Matrix4f transform, @Nonnull IVertexBuilder renderer, float x, float y,
         @Nonnull TextBuffer backgroundColour, @Nonnull Palette palette, boolean greyscale,
         float leftMarginSize, float rightMarginSize, float height
     )
     {
         if( leftMarginSize > 0 )
         {
-            drawQuad( renderer, x - leftMarginSize, y, leftMarginSize, height, palette, greyscale, backgroundColour.charAt( 0 ) );
+            drawQuad( transform, renderer, x - leftMarginSize, y, leftMarginSize, height, palette, greyscale, backgroundColour.charAt( 0 ) );
         }
 
         if( rightMarginSize > 0 )
         {
-            drawQuad( renderer, x + backgroundColour.length() * FONT_WIDTH, y, rightMarginSize, height, palette, greyscale, backgroundColour.charAt( backgroundColour.length() - 1 ) );
+            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.
@@ -134,7 +128,7 @@ public final class FixedWidthFontRenderer
 
             if( blockColour != '\0' )
             {
-                drawQuad( renderer, x + blockStart * FONT_WIDTH, y, FONT_WIDTH * (i - blockStart), height, palette, greyscale, blockColour );
+                drawQuad( transform, renderer, x + blockStart * FONT_WIDTH, y, FONT_WIDTH * (i - blockStart), height, palette, greyscale, blockColour );
             }
 
             blockColour = colourIndex;
@@ -143,24 +137,24 @@ public final class FixedWidthFontRenderer
 
         if( blockColour != '\0' )
         {
-            drawQuad( renderer, x + blockStart * FONT_WIDTH, y, FONT_WIDTH * (backgroundColour.length() - blockStart), height, palette, greyscale, blockColour );
+            drawQuad( transform, renderer, x + blockStart * FONT_WIDTH, y, FONT_WIDTH * (backgroundColour.length() - blockStart), height, palette, greyscale, blockColour );
         }
     }
 
     public static void drawString(
-        @Nonnull BufferBuilder renderer, float x, float y,
+        @Nonnull Matrix4f transform, @Nonnull IVertexBuilder renderer, float x, float y,
         @Nonnull TextBuffer text, @Nonnull TextBuffer textColour, @Nullable TextBuffer backgroundColour,
         @Nonnull Palette palette, boolean greyscale, float leftMarginSize, float rightMarginSize
     )
     {
         if( backgroundColour != null )
         {
-            drawBackground( renderer, x, y, backgroundColour, palette, greyscale, leftMarginSize, rightMarginSize, FONT_HEIGHT );
+            drawBackground( transform, renderer, x, y, backgroundColour, palette, greyscale, leftMarginSize, rightMarginSize, FONT_HEIGHT );
         }
 
         for( int i = 0; i < text.length(); i++ )
         {
-            double[] colour = palette.getColour( getColour( textColour.charAt( i ) ) );
+            double[] colour = palette.getColour( getColour( textColour.charAt( i ), Colour.BLACK ) );
             float r, g, b;
             if( greyscale )
             {
@@ -176,7 +170,7 @@ public final class FixedWidthFontRenderer
             // Draw char
             int index = text.charAt( i );
             if( index > 255 ) index = '?';
-            drawChar( renderer, x + i * FONT_WIDTH, y, index, r, g, b );
+            drawChar( transform, renderer, x + i * FONT_WIDTH, y, index, r, g, b );
         }
 
     }
@@ -188,15 +182,13 @@ public final class FixedWidthFontRenderer
     {
         bindFont();
 
-        Tessellator tessellator = Tessellator.getInstance();
-        BufferBuilder buffer = tessellator.getBuffer();
-        begin( buffer );
-        drawString( buffer, x, y, text, textColour, backgroundColour, palette, greyscale, leftMarginSize, rightMarginSize );
-        tessellator.draw();
+        IRenderTypeBuffer.Impl renderer = Minecraft.getInstance().getRenderTypeBuffers().getBufferSource();
+        drawString( IDENTITY, ((IRenderTypeBuffer) renderer).getBuffer( TYPE ), x, y, text, textColour, backgroundColour, palette, greyscale, leftMarginSize, rightMarginSize );
+        renderer.finish();
     }
 
     public static void drawTerminalWithoutCursor(
-        @Nonnull BufferBuilder buffer, float x, float y,
+        @Nonnull Matrix4f transform, @Nonnull IVertexBuilder buffer, float x, float y,
         @Nonnull Terminal terminal, boolean greyscale,
         float topMarginSize, float bottomMarginSize, float leftMarginSize, float rightMarginSize
     )
@@ -206,13 +198,13 @@ public final class FixedWidthFontRenderer
 
         // Top and bottom margins
         drawBackground(
-            buffer, x, y - topMarginSize,
+            transform, buffer, x, y - topMarginSize,
             terminal.getBackgroundColourLine( 0 ), palette, greyscale,
             leftMarginSize, rightMarginSize, topMarginSize
         );
 
         drawBackground(
-            buffer, x, y + height * FONT_HEIGHT,
+            transform, buffer, x, y + height * FONT_HEIGHT,
             terminal.getBackgroundColourLine( height - 1 ), palette, greyscale,
             leftMarginSize, rightMarginSize, bottomMarginSize
         );
@@ -221,7 +213,7 @@ public final class FixedWidthFontRenderer
         for( int i = 0; i < height; i++ )
         {
             drawString(
-                buffer, x, y + FixedWidthFontRenderer.FONT_HEIGHT * i,
+                transform, buffer, x, y + FixedWidthFontRenderer.FONT_HEIGHT * i,
                 terminal.getLine( i ), terminal.getTextColourLine( i ), terminal.getBackgroundColourLine( i ),
                 palette, greyscale, leftMarginSize, rightMarginSize
             );
@@ -229,7 +221,7 @@ public final class FixedWidthFontRenderer
     }
 
     public static void drawCursor(
-        @Nonnull BufferBuilder buffer, float x, float y,
+        @Nonnull Matrix4f transform, @Nonnull IVertexBuilder buffer, float x, float y,
         @Nonnull Terminal terminal, boolean greyscale
     )
     {
@@ -254,75 +246,104 @@ public final class FixedWidthFontRenderer
                 b = (float) colour[2];
             }
 
-            drawChar( buffer, x + cursorX * FONT_WIDTH, y + cursorY * FONT_HEIGHT, '_', r, g, b );
+            drawChar( transform, buffer, x + cursorX * FONT_WIDTH, y + cursorY * FONT_HEIGHT, '_', r, g, b );
         }
     }
 
     public static void drawTerminal(
-        @Nonnull BufferBuilder buffer, float x, float y,
+        @Nonnull Matrix4f transform, @Nonnull IVertexBuilder buffer, float x, float y,
         @Nonnull Terminal terminal, boolean greyscale,
         float topMarginSize, float bottomMarginSize, float leftMarginSize, float rightMarginSize
     )
     {
-        drawTerminalWithoutCursor( buffer, x, y, terminal, greyscale, topMarginSize, bottomMarginSize, leftMarginSize, rightMarginSize );
-        drawCursor( buffer, x, y, terminal, greyscale );
+        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
+    )
+    {
+        bindFont();
+
+        IRenderTypeBuffer.Impl renderer = Minecraft.getInstance().getRenderTypeBuffers().getBufferSource();
+        IVertexBuilder buffer = renderer.getBuffer( TYPE );
+        drawTerminal( transform, buffer, x, y, terminal, greyscale, topMarginSize, bottomMarginSize, leftMarginSize, rightMarginSize );
+        renderer.finish( TYPE );
     }
 
     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( @Nonnull Matrix4f transform, @Nonnull IRenderTypeBuffer renderer, float x, float y, float width, float height )
+    {
+        Colour colour = Colour.BLACK;
+        drawQuad( transform, renderer.getBuffer( TYPE ), 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 )
     {
         bindFont();
 
-        Tessellator tessellator = Tessellator.getInstance();
-        BufferBuilder buffer = tessellator.getBuffer();
-        begin( buffer );
-        drawTerminal( buffer, x, y, terminal, greyscale, topMarginSize, bottomMarginSize, leftMarginSize, rightMarginSize );
-        tessellator.draw();
+        IRenderTypeBuffer.Impl renderer = Minecraft.getInstance().getRenderTypeBuffers().getBufferSource();
+        drawEmptyTerminal( transform, renderer, x, y, width, height );
+        renderer.finish();
     }
 
     public static void drawEmptyTerminal( float x, float y, float width, float height )
     {
-        bindFont();
-
-        Tessellator tessellator = Tessellator.getInstance();
-        BufferBuilder buffer = tessellator.getBuffer();
-        begin( buffer );
-
-        Colour colour = Colour.Black;
-        drawQuad( buffer, x, y, width, height, colour.getR(), colour.getG(), colour.getB() );
-
-        tessellator.draw();
+        drawEmptyTerminal( IDENTITY, x, y, width, height );
     }
 
-    public static void drawBlocker( @Nonnull BufferBuilder buffer, float x, float y, float width, float height )
+    public static void drawBlocker( @Nonnull Matrix4f transform, @Nonnull IRenderTypeBuffer renderer, float x, float y, float width, float height )
     {
-        Colour colour = Colour.Black;
-        drawQuad( buffer, x, y, width, height, colour.getR(), colour.getG(), colour.getB() );
+        Colour colour = Colour.BLACK;
+        drawQuad( transform, renderer.getBuffer( Type.BLOCKER ), x, y, width, height, colour.getR(), colour.getG(), colour.getB() );
     }
 
-    public static void drawBlocker( float x, float y, float width, float height )
-    {
-        bindFont();
-
-        Tessellator tessellator = Tessellator.getInstance();
-        BufferBuilder buffer = tessellator.getBuffer();
-        begin( buffer );
-        drawBlocker( buffer, x, y, width, height );
-        tessellator.draw();
-    }
-
-    public static void bindFont()
+    private static void bindFont()
     {
         Minecraft.getInstance().getTextureManager().bindTexture( FONT );
-        GlStateManager.texParameter( GL11.GL_TEXTURE_2D, GL11.GL_TEXTURE_WRAP_S, GL11.GL_CLAMP );
-
-        GlStateManager.enableTexture();
+        RenderSystem.texParameter( GL11.GL_TEXTURE_2D, GL11.GL_TEXTURE_WRAP_S, GL11.GL_CLAMP );
     }
 
-    public static void begin( BufferBuilder buffer )
+    private static final class Type extends RenderState
     {
-        buffer.begin( GL11.GL_TRIANGLES, POSITION_COLOR_TEX );
+        private static final int GL_MODE = GL11.GL_TRIANGLES;
+
+        private static final VertexFormat FORMAT = DefaultVertexFormats.POSITION_COLOR_TEX;
+
+        static final RenderType MAIN = RenderType.makeType(
+            "terminal_font", FORMAT, GL_MODE, 1024,
+            false, false, // useDelegate, needsSorting
+            RenderType.State.getBuilder()
+                .texture( new RenderState.TextureState( FONT, false, false ) ) // blur, minimap
+                .alpha( DEFAULT_ALPHA )
+                .lightmap( LIGHTMAP_DISABLED )
+                .writeMask( COLOR_WRITE )
+                .build( false )
+        );
+
+        static final RenderType BLOCKER = RenderType.makeType(
+            "terminal_blocker", FORMAT, GL_MODE, 256,
+            false, false, // useDelegate, needsSorting
+            RenderType.State.getBuilder()
+                .texture( new RenderState.TextureState( FONT, false, false ) ) // blur, minimap
+                .alpha( DEFAULT_ALPHA )
+                .writeMask( DEPTH_WRITE )
+                .lightmap( LIGHTMAP_DISABLED )
+                .build( false )
+        );
+
+        private Type( String name, Runnable setup, Runnable destroy )
+        {
+            super( name, setup, destroy );
+        }
     }
 }

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

@@ -5,10 +5,12 @@
  */
 package dan200.computercraft.client.gui;
 
-import com.mojang.blaze3d.platform.GlStateManager;
+import com.mojang.blaze3d.matrix.MatrixStack;
+import com.mojang.blaze3d.systems.RenderSystem;
 import dan200.computercraft.ComputerCraft;
 import dan200.computercraft.client.gui.widgets.WidgetTerminal;
 import dan200.computercraft.client.gui.widgets.WidgetWrapper;
+import dan200.computercraft.client.render.ComputerBorderRenderer;
 import dan200.computercraft.shared.computer.core.ClientComputer;
 import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.computer.inventory.ContainerComputer;
@@ -17,21 +19,20 @@ import dan200.computercraft.shared.computer.inventory.ContainerViewComputer;
 import dan200.computercraft.shared.pocket.inventory.ContainerPocketComputer;
 import net.minecraft.client.gui.screen.inventory.ContainerScreen;
 import net.minecraft.entity.player.PlayerInventory;
-import net.minecraft.util.ResourceLocation;
 import net.minecraft.util.text.ITextComponent;
 import org.lwjgl.glfw.GLFW;
 
+import javax.annotation.Nonnull;
+
+import static dan200.computercraft.client.render.ComputerBorderRenderer.BORDER;
+import static dan200.computercraft.client.render.ComputerBorderRenderer.MARGIN;
+
 public final class GuiComputer<T extends ContainerComputerBase> extends ContainerScreen<T>
 {
-    public static final ResourceLocation BACKGROUND_NORMAL = new ResourceLocation( ComputerCraft.MOD_ID, "textures/gui/corners_normal.png" );
-    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 final ComputerFamily m_family;
-    private final ClientComputer m_computer;
-    private final int m_termWidth;
-    private final int m_termHeight;
+    private final ComputerFamily family;
+    private final ClientComputer computer;
+    private final int termWidth;
+    private final int termHeight;
 
     private WidgetTerminal terminal;
     private WidgetWrapper terminalWrapper;
@@ -41,10 +42,10 @@ public final class GuiComputer<T extends ContainerComputerBase> extends Containe
     )
     {
         super( container, player, title );
-        m_family = container.getFamily();
-        m_computer = (ClientComputer) container.getComputer();
-        m_termWidth = termWidth;
-        m_termHeight = termHeight;
+        family = container.getFamily();
+        computer = (ClientComputer) container.getComputer();
+        this.termWidth = termWidth;
+        this.termHeight = termHeight;
         terminal = null;
     }
 
@@ -52,7 +53,7 @@ public final class GuiComputer<T extends ContainerComputerBase> extends Containe
     {
         return new GuiComputer<>(
             container, inventory, component,
-            ComputerCraft.terminalWidth_computer, ComputerCraft.terminalHeight_computer
+            ComputerCraft.computerTermWidth, ComputerCraft.computerTermHeight
         );
     }
 
@@ -60,7 +61,7 @@ public final class GuiComputer<T extends ContainerComputerBase> extends Containe
     {
         return new GuiComputer<>(
             container, inventory, component,
-            ComputerCraft.terminalWidth_pocketComputer, ComputerCraft.terminalHeight_pocketComputer
+            ComputerCraft.pocketTermWidth, ComputerCraft.pocketTermHeight
         );
     }
 
@@ -78,25 +79,25 @@ public final class GuiComputer<T extends ContainerComputerBase> extends Containe
     {
         minecraft.keyboardListener.enableRepeatEvents( true );
 
-        int termPxWidth = m_termWidth * FixedWidthFontRenderer.FONT_WIDTH;
-        int termPxHeight = m_termHeight * FixedWidthFontRenderer.FONT_HEIGHT;
+        int termPxWidth = termWidth * FixedWidthFontRenderer.FONT_WIDTH;
+        int termPxHeight = termHeight * FixedWidthFontRenderer.FONT_HEIGHT;
 
-        xSize = termPxWidth + 4 + 24;
-        ySize = termPxHeight + 4 + 24;
+        xSize = termPxWidth + MARGIN * 2 + BORDER * 2;
+        ySize = termPxHeight + MARGIN * 2 + BORDER * 2;
 
         super.init();
 
-        terminal = new WidgetTerminal( minecraft, () -> m_computer, m_termWidth, m_termHeight, 2, 2, 2, 2 );
-        terminalWrapper = new WidgetWrapper( terminal, 2 + 12 + guiLeft, 2 + 12 + guiTop, termPxWidth, termPxHeight );
+        terminal = new WidgetTerminal( minecraft, () -> computer, termWidth, termHeight, MARGIN, MARGIN, MARGIN, MARGIN );
+        terminalWrapper = new WidgetWrapper( terminal, MARGIN + BORDER + guiLeft, MARGIN + BORDER + guiTop, termPxWidth, termPxHeight );
 
         children.add( terminalWrapper );
-        setFocused( terminalWrapper );
+        setListener( terminalWrapper );
     }
 
     @Override
-    public void removed()
+    public void onClose()
     {
-        super.removed();
+        super.onClose();
         children.remove( terminal );
         terminal = null;
         minecraft.keyboardListener.enableRepeatEvents( false );
@@ -113,66 +114,46 @@ public final class GuiComputer<T extends ContainerComputerBase> extends Containe
     public boolean keyPressed( int key, int scancode, int modifiers )
     {
         // Forward the tab key to the terminal, rather than moving between controls.
-        if( key == GLFW.GLFW_KEY_TAB && getFocused() != null && getFocused() == terminalWrapper )
+        if( key == GLFW.GLFW_KEY_TAB && getListener() != null && getListener() == terminalWrapper )
         {
-            return getFocused().keyPressed( key, scancode, modifiers );
+            return getListener().keyPressed( key, scancode, modifiers );
         }
 
         return super.keyPressed( key, scancode, modifiers );
     }
 
     @Override
-    public void drawGuiContainerBackgroundLayer( float partialTicks, int mouseX, int mouseY )
+    public void drawGuiContainerBackgroundLayer( @Nonnull MatrixStack stack, float partialTicks, int mouseX, int mouseY )
     {
-        // Work out where to draw
-        int startX = terminalWrapper.getX() - 2;
-        int startY = terminalWrapper.getY() - 2;
-        int endX = startX + terminalWrapper.getWidth() + 4;
-        int endY = startY + terminalWrapper.getHeight() + 4;
-
         // Draw terminal
         terminal.draw( terminalWrapper.getX(), terminalWrapper.getY() );
 
         // Draw a border around the terminal
-        GlStateManager.color4f( 1.0f, 1.0f, 1.0f, 1.0f );
-        switch( m_family )
-        {
-            case Normal:
-            default:
-                minecraft.getTextureManager().bindTexture( BACKGROUND_NORMAL );
-                break;
-            case Advanced:
-                minecraft.getTextureManager().bindTexture( BACKGROUND_ADVANCED );
-                break;
-            case Command:
-                minecraft.getTextureManager().bindTexture( BACKGROUND_COMMAND );
-                break;
-        }
-
-        blit( startX - 12, startY - 12, 12, 28, 12, 12 );
-        blit( startX - 12, endY, 12, 40, 12, 12 );
-        blit( endX, startY - 12, 24, 28, 12, 12 );
-        blit( endX, endY, 24, 40, 12, 12 );
-
-        blit( startX, startY - 12, 0, 0, endX - startX, 12 );
-        blit( startX, endY, 0, 12, endX - startX, 12 );
-
-        blit( startX - 12, startY, 0, 28, 12, endY - startY );
-        blit( endX, startY, 36, 28, 12, endY - startY );
+        RenderSystem.color4f( 1, 1, 1, 1 );
+        minecraft.getTextureManager().bindTexture( ComputerBorderRenderer.getTexture( family ) );
+        ComputerBorderRenderer.render(
+            terminalWrapper.getX() - MARGIN, terminalWrapper.getY() - MARGIN, getBlitOffset(),
+            terminalWrapper.getWidth() + MARGIN * 2, terminalWrapper.getHeight() + MARGIN * 2
+        );
     }
 
     @Override
-    public void render( int mouseX, int mouseY, float partialTicks )
+    public void render( @Nonnull MatrixStack stack, int mouseX, int mouseY, float partialTicks )
     {
-        renderBackground();
-        super.render( mouseX, mouseY, partialTicks );
-        renderHoveredToolTip( mouseX, mouseY );
+        super.render( stack, mouseX, mouseY, partialTicks );
+        func_230459_a_( stack, mouseX, mouseY );
     }
 
     @Override
     public boolean mouseDragged( double x, double y, int button, double deltaX, double deltaY )
     {
-        return (getFocused() != null && getFocused().mouseDragged( x, y, button, deltaX, deltaY ))
+        return (getListener() != null && getListener().mouseDragged( x, y, button, deltaX, deltaY ))
             || super.mouseDragged( x, y, button, deltaX, deltaY );
     }
+
+    @Override
+    protected void drawGuiContainerForegroundLayer( @Nonnull MatrixStack transform, int mouseX, int mouseY )
+    {
+        // Skip rendering labels.
+    }
 }

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

@@ -5,13 +5,16 @@
  */
 package dan200.computercraft.client.gui;
 
-import com.mojang.blaze3d.platform.GlStateManager;
+import com.mojang.blaze3d.matrix.MatrixStack;
+import com.mojang.blaze3d.systems.RenderSystem;
 import dan200.computercraft.shared.peripheral.diskdrive.ContainerDiskDrive;
 import net.minecraft.client.gui.screen.inventory.ContainerScreen;
 import net.minecraft.entity.player.PlayerInventory;
 import net.minecraft.util.ResourceLocation;
 import net.minecraft.util.text.ITextComponent;
 
+import javax.annotation.Nonnull;
+
 public class GuiDiskDrive extends ContainerScreen<ContainerDiskDrive>
 {
     private static final ResourceLocation BACKGROUND = new ResourceLocation( "computercraft", "textures/gui/disk_drive.png" );
@@ -22,26 +25,18 @@ public class GuiDiskDrive extends ContainerScreen<ContainerDiskDrive>
     }
 
     @Override
-    protected void drawGuiContainerForegroundLayer( int mouseX, int mouseY )
+    protected void drawGuiContainerBackgroundLayer( @Nonnull MatrixStack transform, float partialTicks, int mouseX, int mouseY )
     {
-        String title = this.title.getFormattedText();
-        font.drawString( title, (xSize - font.getStringWidth( title )) / 2.0f, 6, 0x404040 );
-        font.drawString( title, 8, ySize - 96 + 2, 0x404040 );
-    }
-
-    @Override
-    protected void drawGuiContainerBackgroundLayer( float partialTicks, int mouseX, int mouseY )
-    {
-        GlStateManager.color4f( 1.0F, 1.0F, 1.0F, 1.0F );
+        RenderSystem.color4f( 1.0F, 1.0F, 1.0F, 1.0F );
         minecraft.getTextureManager().bindTexture( BACKGROUND );
-        blit( guiLeft, guiTop, 0, 0, xSize, ySize );
+        blit( transform, guiLeft, guiTop, 0, 0, xSize, ySize );
     }
 
     @Override
-    public void render( int mouseX, int mouseY, float partialTicks )
+    public void render( @Nonnull MatrixStack transform, int mouseX, int mouseY, float partialTicks )
     {
-        renderBackground();
-        super.render( mouseX, mouseY, partialTicks );
-        renderHoveredToolTip( mouseX, mouseY );
+        renderBackground( transform );
+        super.render( transform, mouseX, mouseY, partialTicks );
+        func_230459_a_( transform, mouseX, mouseY );
     }
 }

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

@@ -5,14 +5,16 @@
  */
 package dan200.computercraft.client.gui;
 
-import com.mojang.blaze3d.platform.GlStateManager;
+import com.mojang.blaze3d.matrix.MatrixStack;
+import com.mojang.blaze3d.systems.RenderSystem;
 import dan200.computercraft.shared.peripheral.printer.ContainerPrinter;
 import net.minecraft.client.gui.screen.inventory.ContainerScreen;
-import net.minecraft.client.resources.I18n;
 import net.minecraft.entity.player.PlayerInventory;
 import net.minecraft.util.ResourceLocation;
 import net.minecraft.util.text.ITextComponent;
 
+import javax.annotation.Nonnull;
+
 public class GuiPrinter extends ContainerScreen<ContainerPrinter>
 {
     private static final ResourceLocation BACKGROUND = new ResourceLocation( "computercraft", "textures/gui/printer.png" );
@@ -22,29 +24,29 @@ public class GuiPrinter extends ContainerScreen<ContainerPrinter>
         super( container, player, title );
     }
 
-    @Override
+    /*@Override
     protected void drawGuiContainerForegroundLayer( int mouseX, int mouseY )
     {
         String title = getTitle().getFormattedText();
         font.drawString( title, (xSize - font.getStringWidth( title )) / 2.0f, 6, 0x404040 );
         font.drawString( I18n.format( "container.inventory" ), 8, ySize - 96 + 2, 0x404040 );
-    }
+    }*/
 
     @Override
-    protected void drawGuiContainerBackgroundLayer( float partialTicks, int mouseX, int mouseY )
+    protected void drawGuiContainerBackgroundLayer( @Nonnull MatrixStack transform, float partialTicks, int mouseX, int mouseY )
     {
-        GlStateManager.color4f( 1.0F, 1.0F, 1.0F, 1.0F );
+        RenderSystem.color4f( 1.0F, 1.0F, 1.0F, 1.0F );
         minecraft.getTextureManager().bindTexture( BACKGROUND );
-        blit( guiLeft, guiTop, 0, 0, xSize, ySize );
+        blit( transform, guiLeft, guiTop, 0, 0, xSize, ySize );
 
-        if( getContainer().isPrinting() ) blit( guiLeft + 34, guiTop + 21, 176, 0, 25, 45 );
+        if( getContainer().isPrinting() ) blit( transform, guiLeft + 34, guiTop + 21, 176, 0, 25, 45 );
     }
 
     @Override
-    public void render( int mouseX, int mouseY, float partialTicks )
+    public void render( @Nonnull MatrixStack stack, int mouseX, int mouseY, float partialTicks )
     {
-        renderBackground();
-        super.render( mouseX, mouseY, partialTicks );
-        renderHoveredToolTip( mouseX, mouseY );
+        renderBackground( stack );
+        super.render( stack, mouseX, mouseY, partialTicks );
+        func_230459_a_( stack, mouseX, mouseY );
     }
 }

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

@@ -5,15 +5,21 @@
  */
 package dan200.computercraft.client.gui;
 
-import com.mojang.blaze3d.platform.GlStateManager;
+import com.mojang.blaze3d.matrix.MatrixStack;
+import com.mojang.blaze3d.systems.RenderSystem;
 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.screen.inventory.ContainerScreen;
+import net.minecraft.client.renderer.IRenderTypeBuffer;
 import net.minecraft.entity.player.PlayerInventory;
+import net.minecraft.util.math.vector.Matrix4f;
 import net.minecraft.util.text.ITextComponent;
 import org.lwjgl.glfw.GLFW;
 
+import javax.annotation.Nonnull;
+
 import static dan200.computercraft.client.render.PrintoutRenderer.*;
 
 public class GuiPrintout extends ContainerScreen<ContainerHeldItem>
@@ -85,25 +91,33 @@ public class GuiPrintout extends ContainerScreen<ContainerHeldItem>
     }
 
     @Override
-    public void drawGuiContainerBackgroundLayer( float partialTicks, int mouseX, int mouseY )
+    protected void drawGuiContainerBackgroundLayer( @Nonnull MatrixStack transform, float partialTicks, int mouseX, int mouseY )
     {
         // Draw the printout
-        GlStateManager.color4f( 1.0f, 1.0f, 1.0f, 1.0f );
-        GlStateManager.enableDepthTest();
+        RenderSystem.color4f( 1.0f, 1.0f, 1.0f, 1.0f );
+        RenderSystem.enableDepthTest();
 
-        drawBorder( guiLeft, guiTop, blitOffset, m_page, m_pages, m_book );
-        drawText( guiLeft + X_TEXT_MARGIN, guiTop + Y_TEXT_MARGIN, ItemPrintout.LINES_PER_PAGE * m_page, m_text, m_colours );
+        IRenderTypeBuffer.Impl renderer = Minecraft.getInstance().getRenderTypeBuffers().getBufferSource();
+        Matrix4f matrix = transform.getLast().getMatrix();
+        drawBorder( matrix, renderer, guiLeft, guiTop, getBlitOffset(), m_page, m_pages, m_book );
+        drawText( matrix, renderer, guiLeft + X_TEXT_MARGIN, guiTop + Y_TEXT_MARGIN, ItemPrintout.LINES_PER_PAGE * m_page, m_text, m_colours );
+        renderer.finish();
     }
 
     @Override
-    public void render( int mouseX, int mouseY, float partialTicks )
+    public void render( @Nonnull MatrixStack stack, int mouseX, int mouseY, float partialTicks )
     {
         // We must take the background further back in order to not overlap with our printed pages.
-        blitOffset--;
-        renderBackground();
-        blitOffset++;
+        setBlitOffset( getBlitOffset() - 1 );
+        renderBackground( stack );
+        setBlitOffset( getBlitOffset() + 1 );
 
-        super.render( mouseX, mouseY, partialTicks );
-        renderHoveredToolTip( mouseX, mouseY );
+        super.render( stack, mouseX, mouseY, partialTicks );
+    }
+
+    @Override
+    protected void drawGuiContainerForegroundLayer( @Nonnull MatrixStack transform, int mouseX, int mouseY )
+    {
+        // Skip rendering labels.
     }
 }

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

@@ -5,7 +5,8 @@
  */
 package dan200.computercraft.client.gui;
 
-import com.mojang.blaze3d.platform.GlStateManager;
+import com.mojang.blaze3d.matrix.MatrixStack;
+import com.mojang.blaze3d.systems.RenderSystem;
 import dan200.computercraft.ComputerCraft;
 import dan200.computercraft.client.gui.widgets.WidgetTerminal;
 import dan200.computercraft.client.gui.widgets.WidgetWrapper;
@@ -18,6 +19,8 @@ import net.minecraft.util.ResourceLocation;
 import net.minecraft.util.text.ITextComponent;
 import org.lwjgl.glfw.GLFW;
 
+import javax.annotation.Nonnull;
+
 public class GuiTurtle extends ContainerScreen<ContainerTurtle>
 {
     private static final ResourceLocation BACKGROUND_NORMAL = new ResourceLocation( "computercraft", "textures/gui/turtle_normal.png" );
@@ -49,25 +52,25 @@ public class GuiTurtle extends ContainerScreen<ContainerTurtle>
         super.init();
         minecraft.keyboardListener.enableRepeatEvents( true );
 
-        int termPxWidth = ComputerCraft.terminalWidth_turtle * FixedWidthFontRenderer.FONT_WIDTH;
-        int termPxHeight = ComputerCraft.terminalHeight_turtle * FixedWidthFontRenderer.FONT_HEIGHT;
+        int termPxWidth = ComputerCraft.turtleTermWidth * FixedWidthFontRenderer.FONT_WIDTH;
+        int termPxHeight = ComputerCraft.turtleTermHeight * FixedWidthFontRenderer.FONT_HEIGHT;
 
         terminal = new WidgetTerminal(
             minecraft, () -> m_computer,
-            ComputerCraft.terminalWidth_turtle,
-            ComputerCraft.terminalHeight_turtle,
+            ComputerCraft.turtleTermWidth,
+            ComputerCraft.turtleTermHeight,
             2, 2, 2, 2
         );
         terminalWrapper = new WidgetWrapper( terminal, 2 + 8 + guiLeft, 2 + 8 + guiTop, termPxWidth, termPxHeight );
 
         children.add( terminalWrapper );
-        setFocused( terminalWrapper );
+        setListener( terminalWrapper );
     }
 
     @Override
-    public void removed()
+    public void onClose()
     {
-        super.removed();
+        super.onClose();
         children.remove( terminal );
         terminal = null;
         minecraft.keyboardListener.enableRepeatEvents( false );
@@ -84,55 +87,58 @@ public class GuiTurtle extends ContainerScreen<ContainerTurtle>
     public boolean keyPressed( int key, int scancode, int modifiers )
     {
         // Forward the tab key to the terminal, rather than moving between controls.
-        if( key == GLFW.GLFW_KEY_TAB && getFocused() != null && getFocused() == terminalWrapper )
+        if( key == GLFW.GLFW_KEY_TAB && getListener() != null && getListener() == terminalWrapper )
         {
-            return getFocused().keyPressed( key, scancode, modifiers );
+            return getListener().keyPressed( key, scancode, modifiers );
         }
 
         return super.keyPressed( key, scancode, modifiers );
     }
 
-    private void drawSelectionSlot( boolean advanced )
+    @Override
+    protected void drawGuiContainerBackgroundLayer( @Nonnull MatrixStack transform, float partialTicks, int mouseX, int mouseY )
     {
+        // Draw term
+        ResourceLocation texture = m_family == ComputerFamily.ADVANCED ? BACKGROUND_ADVANCED : BACKGROUND_NORMAL;
+        terminal.draw( terminalWrapper.getX(), terminalWrapper.getY() );
+
+        // Draw border/inventory
+        RenderSystem.color4f( 1.0F, 1.0F, 1.0F, 1.0F );
+        minecraft.getTextureManager().bindTexture( texture );
+        blit( transform, guiLeft, guiTop, 0, 0, xSize, ySize );
+
         // Draw selection slot
         int slot = m_container.getSelectedSlot();
         if( slot >= 0 )
         {
-            GlStateManager.color4f( 1.0F, 1.0F, 1.0F, 1.0F );
             int slotX = slot % 4;
             int slotY = slot / 4;
-            minecraft.getTextureManager().bindTexture( advanced ? BACKGROUND_ADVANCED : BACKGROUND_NORMAL );
-            blit( guiLeft + ContainerTurtle.TURTLE_START_X - 2 + slotX * 18, guiTop + ContainerTurtle.PLAYER_START_Y - 2 + slotY * 18, 0, 217, 24, 24 );
+            blit( transform,
+                guiLeft + ContainerTurtle.TURTLE_START_X - 2 + slotX * 18,
+                guiTop + ContainerTurtle.PLAYER_START_Y - 2 + slotY * 18,
+                0, 217, 24, 24
+            );
         }
     }
 
     @Override
-    protected void drawGuiContainerBackgroundLayer( float partialTicks, int mouseX, int mouseY )
+    public void render( @Nonnull MatrixStack stack, int mouseX, int mouseY, float partialTicks )
     {
-        // Draw term
-        boolean advanced = m_family == ComputerFamily.Advanced;
-        terminal.draw( terminalWrapper.getX(), terminalWrapper.getY() );
-
-        // Draw border/inventory
-        GlStateManager.color4f( 1.0F, 1.0F, 1.0F, 1.0F );
-        minecraft.getTextureManager().bindTexture( advanced ? BACKGROUND_ADVANCED : BACKGROUND_NORMAL );
-        blit( guiLeft, guiTop, 0, 0, xSize, ySize );
-
-        drawSelectionSlot( advanced );
-    }
-
-    @Override
-    public void render( int mouseX, int mouseY, float partialTicks )
-    {
-        renderBackground();
-        super.render( mouseX, mouseY, partialTicks );
-        renderHoveredToolTip( mouseX, mouseY );
+        renderBackground( stack );
+        super.render( stack, mouseX, mouseY, partialTicks );
+        func_230459_a_( stack, mouseX, mouseY );
     }
 
     @Override
     public boolean mouseDragged( double x, double y, int button, double deltaX, double deltaY )
     {
-        return (getFocused() != null && getFocused().mouseDragged( x, y, button, deltaX, deltaY ))
+        return (getListener() != null && getListener().mouseDragged( x, y, button, deltaX, deltaY ))
             || super.mouseDragged( x, y, button, deltaX, deltaY );
     }
+
+    @Override
+    protected void drawGuiContainerForegroundLayer( @Nonnull MatrixStack transform, int mouseX, int mouseY )
+    {
+        // Skip rendering labels.
+    }
 }

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

@@ -17,6 +17,9 @@ import org.lwjgl.glfw.GLFW;
 import java.util.BitSet;
 import java.util.function.Supplier;
 
+import static dan200.computercraft.client.gui.FixedWidthFontRenderer.FONT_HEIGHT;
+import static dan200.computercraft.client.gui.FixedWidthFontRenderer.FONT_WIDTH;
+
 public class WidgetTerminal implements IGuiEventListener
 {
     private static final float TERMINATE_TIME = 0.5f;
@@ -173,8 +176,8 @@ public class WidgetTerminal implements IGuiEventListener
         Terminal term = computer.getTerminal();
         if( term != null )
         {
-            int charX = (int) (mouseX / FixedWidthFontRenderer.FONT_WIDTH);
-            int charY = (int) (mouseY / FixedWidthFontRenderer.FONT_HEIGHT);
+            int charX = (int) (mouseX / FONT_WIDTH);
+            int charY = (int) (mouseY / FONT_HEIGHT);
             charX = Math.min( Math.max( charX, 0 ), term.getWidth() - 1 );
             charY = Math.min( Math.max( charY, 0 ), term.getHeight() - 1 );
 
@@ -197,8 +200,8 @@ public class WidgetTerminal implements IGuiEventListener
         Terminal term = computer.getTerminal();
         if( term != null )
         {
-            int charX = (int) (mouseX / FixedWidthFontRenderer.FONT_WIDTH);
-            int charY = (int) (mouseY / FixedWidthFontRenderer.FONT_HEIGHT);
+            int charX = (int) (mouseX / FONT_WIDTH);
+            int charY = (int) (mouseY / FONT_HEIGHT);
             charX = Math.min( Math.max( charX, 0 ), term.getWidth() - 1 );
             charY = Math.min( Math.max( charY, 0 ), term.getHeight() - 1 );
 
@@ -224,8 +227,8 @@ public class WidgetTerminal implements IGuiEventListener
         Terminal term = computer.getTerminal();
         if( term != null )
         {
-            int charX = (int) (mouseX / FixedWidthFontRenderer.FONT_WIDTH);
-            int charY = (int) (mouseY / FixedWidthFontRenderer.FONT_HEIGHT);
+            int charX = (int) (mouseX / FONT_WIDTH);
+            int charY = (int) (mouseY / FONT_HEIGHT);
             charX = Math.min( Math.max( charX, 0 ), term.getWidth() - 1 );
             charY = Math.min( Math.max( charY, 0 ), term.getHeight() - 1 );
 
@@ -249,8 +252,8 @@ public class WidgetTerminal implements IGuiEventListener
         Terminal term = computer.getTerminal();
         if( term != null )
         {
-            int charX = (int) (mouseX / FixedWidthFontRenderer.FONT_WIDTH);
-            int charY = (int) (mouseY / FixedWidthFontRenderer.FONT_HEIGHT);
+            int charX = (int) (mouseX / FONT_WIDTH);
+            int charY = (int) (mouseY / FONT_HEIGHT);
             charX = Math.min( Math.max( charX, 0 ), term.getWidth() - 1 );
             charY = Math.min( Math.max( charY, 0 ), term.getHeight() - 1 );
 
@@ -318,19 +321,15 @@ public class WidgetTerminal implements IGuiEventListener
             Terminal terminal = computer != null ? computer.getTerminal() : null;
             if( terminal != null )
             {
-                FixedWidthFontRenderer.drawTerminal(
-                    originX, originY,
-                    terminal, !computer.isColour(), topMargin, bottomMargin, leftMargin, rightMargin
-                );
+                FixedWidthFontRenderer.drawTerminal( originX, originY, terminal, !computer.isColour(), topMargin, bottomMargin, leftMargin, rightMargin );
             }
             else
             {
-                int x = originX - leftMargin;
-                int y = originY - rightMargin;
-                int width = termWidth * FixedWidthFontRenderer.FONT_WIDTH + leftMargin + rightMargin;
-                int height = termHeight * FixedWidthFontRenderer.FONT_HEIGHT + topMargin + bottomMargin;
-
-                FixedWidthFontRenderer.drawEmptyTerminal( x, y, width, height );
+                FixedWidthFontRenderer.drawEmptyTerminal(
+                    originX - leftMargin, originY - rightMargin,
+                    termWidth * FONT_WIDTH + leftMargin + rightMargin,
+                    termHeight * FONT_HEIGHT + topMargin + bottomMargin
+                );
             }
         }
     }

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

@@ -7,23 +7,23 @@ package dan200.computercraft.client.proxy;
 
 import dan200.computercraft.ComputerCraft;
 import dan200.computercraft.client.gui.*;
-import dan200.computercraft.client.render.TileEntityCableRenderer;
 import dan200.computercraft.client.render.TileEntityMonitorRenderer;
 import dan200.computercraft.client.render.TileEntityTurtleRenderer;
 import dan200.computercraft.client.render.TurtlePlayerRenderer;
-import dan200.computercraft.shared.common.ContainerHeldItem;
+import dan200.computercraft.shared.Registry;
+import dan200.computercraft.shared.common.IColouredItem;
 import dan200.computercraft.shared.computer.inventory.ContainerComputer;
 import dan200.computercraft.shared.computer.inventory.ContainerViewComputer;
-import dan200.computercraft.shared.peripheral.diskdrive.ContainerDiskDrive;
-import dan200.computercraft.shared.peripheral.modem.wired.TileCable;
 import dan200.computercraft.shared.peripheral.monitor.ClientMonitor;
-import dan200.computercraft.shared.peripheral.monitor.TileMonitor;
-import dan200.computercraft.shared.peripheral.printer.ContainerPrinter;
 import dan200.computercraft.shared.pocket.inventory.ContainerPocketComputer;
-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.pocket.items.ItemPocketComputer;
 import net.minecraft.client.gui.ScreenManager;
+import net.minecraft.client.renderer.RenderType;
+import net.minecraft.client.renderer.RenderTypeLookup;
+import net.minecraft.item.IItemPropertyGetter;
+import net.minecraft.item.Item;
+import net.minecraft.item.ItemModelsProperties;
+import net.minecraft.util.ResourceLocation;
 import net.minecraftforge.api.distmarker.Dist;
 import net.minecraftforge.event.world.WorldEvent;
 import net.minecraftforge.eventbus.api.SubscribeEvent;
@@ -32,6 +32,8 @@ import net.minecraftforge.fml.client.registry.RenderingRegistry;
 import net.minecraftforge.fml.common.Mod;
 import net.minecraftforge.fml.event.lifecycle.FMLClientSetupEvent;
 
+import java.util.function.Supplier;
+
 @Mod.EventBusSubscriber( modid = ComputerCraft.MOD_ID, value = Dist.CLIENT, bus = Mod.EventBusSubscriber.Bus.MOD )
 public final class ComputerCraftProxyClient
 {
@@ -40,27 +42,56 @@ public final class ComputerCraftProxyClient
     {
         registerContainers();
 
-        // Setup TESRs
-        ClientRegistry.bindTileEntitySpecialRenderer( TileMonitor.class, new TileEntityMonitorRenderer() );
-        ClientRegistry.bindTileEntitySpecialRenderer( TileCable.class, new TileEntityCableRenderer() );
-        ClientRegistry.bindTileEntitySpecialRenderer( TileTurtle.class, new TileEntityTurtleRenderer() );
+        // While turtles themselves are not transparent, their upgrades may be.
+        RenderTypeLookup.setRenderLayer( Registry.ModBlocks.TURTLE_NORMAL.get(), RenderType.getTranslucent() );
+        RenderTypeLookup.setRenderLayer( Registry.ModBlocks.TURTLE_ADVANCED.get(), RenderType.getTranslucent() );
 
-        RenderingRegistry.registerEntityRenderingHandler( TurtlePlayer.class, TurtlePlayerRenderer::new );
+        // Monitors' textures have transparent fronts and so count as cutouts.
+        RenderTypeLookup.setRenderLayer( Registry.ModBlocks.MONITOR_NORMAL.get(), RenderType.getCutout() );
+        RenderTypeLookup.setRenderLayer( Registry.ModBlocks.MONITOR_ADVANCED.get(), RenderType.getCutout() );
+
+        // Setup TESRs
+        ClientRegistry.bindTileEntityRenderer( Registry.ModTiles.MONITOR_NORMAL.get(), TileEntityMonitorRenderer::new );
+        ClientRegistry.bindTileEntityRenderer( Registry.ModTiles.MONITOR_ADVANCED.get(), TileEntityMonitorRenderer::new );
+        ClientRegistry.bindTileEntityRenderer( Registry.ModTiles.TURTLE_NORMAL.get(), TileEntityTurtleRenderer::new );
+        ClientRegistry.bindTileEntityRenderer( Registry.ModTiles.TURTLE_ADVANCED.get(), TileEntityTurtleRenderer::new );
+        // TODO: ClientRegistry.bindTileEntityRenderer( TileCable.FACTORY, x -> new TileEntityCableRenderer() );
+
+        RenderingRegistry.registerEntityRenderingHandler( Registry.ModEntities.TURTLE_PLAYER.get(), TurtlePlayerRenderer::new );
+
+        registerItemProperty( "state",
+            ( stack, world, player ) -> ItemPocketComputer.getState( stack ).ordinal(),
+            Registry.ModItems.POCKET_COMPUTER_NORMAL, Registry.ModItems.POCKET_COMPUTER_ADVANCED
+        );
+        registerItemProperty( "state",
+            ( stack, world, player ) -> IColouredItem.getColourBasic( stack ) != -1 ? 1 : 0,
+            Registry.ModItems.POCKET_COMPUTER_NORMAL, Registry.ModItems.POCKET_COMPUTER_ADVANCED
+        );
+    }
+
+    @SafeVarargs
+    private static void registerItemProperty( String name, IItemPropertyGetter getter, Supplier<? extends Item>... items )
+    {
+        ResourceLocation id = new ResourceLocation( ComputerCraft.MOD_ID, name );
+        for( Supplier<? extends Item> item : items )
+        {
+            ItemModelsProperties.func_239418_a_( item.get(), id, getter );
+        }
     }
 
     private static void registerContainers()
     {
         // My IDE doesn't think so, but we do actually need these generics.
 
-        ScreenManager.<ContainerComputer, GuiComputer<ContainerComputer>>registerFactory( ContainerComputer.TYPE, GuiComputer::create );
-        ScreenManager.<ContainerPocketComputer, GuiComputer<ContainerPocketComputer>>registerFactory( ContainerPocketComputer.TYPE, GuiComputer::createPocket );
-        ScreenManager.registerFactory( ContainerTurtle.TYPE, GuiTurtle::new );
+        ScreenManager.<ContainerComputer, GuiComputer<ContainerComputer>>registerFactory( Registry.ModContainers.COMPUTER.get(), GuiComputer::create );
+        ScreenManager.<ContainerPocketComputer, GuiComputer<ContainerPocketComputer>>registerFactory( Registry.ModContainers.POCKET_COMPUTER.get(), GuiComputer::createPocket );
+        ScreenManager.registerFactory( Registry.ModContainers.TURTLE.get(), GuiTurtle::new );
 
-        ScreenManager.registerFactory( ContainerPrinter.TYPE, GuiPrinter::new );
-        ScreenManager.registerFactory( ContainerDiskDrive.TYPE, GuiDiskDrive::new );
-        ScreenManager.registerFactory( ContainerHeldItem.PRINTOUT_TYPE, GuiPrintout::new );
+        ScreenManager.registerFactory( Registry.ModContainers.PRINTER.get(), GuiPrinter::new );
+        ScreenManager.registerFactory( Registry.ModContainers.DISK_DRIVE.get(), GuiDiskDrive::new );
+        ScreenManager.registerFactory( Registry.ModContainers.PRINTOUT.get(), GuiPrintout::new );
 
-        ScreenManager.<ContainerViewComputer, GuiComputer<ContainerViewComputer>>registerFactory( ContainerViewComputer.TYPE, GuiComputer::createView );
+        ScreenManager.<ContainerViewComputer, GuiComputer<ContainerViewComputer>>registerFactory( Registry.ModContainers.VIEW_COMPUTER.get(), GuiComputer::createView );
     }
 
     @Mod.EventBusSubscriber( modid = ComputerCraft.MOD_ID, value = Dist.CLIENT )

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

@@ -5,26 +5,28 @@
  */
 package dan200.computercraft.client.render;
 
-import com.mojang.blaze3d.platform.GlStateManager;
+import com.mojang.blaze3d.matrix.MatrixStack;
+import com.mojang.blaze3d.vertex.IVertexBuilder;
 import dan200.computercraft.ComputerCraft;
+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;
 import net.minecraft.block.BlockState;
-import net.minecraft.client.Minecraft;
 import net.minecraft.client.renderer.ActiveRenderInfo;
+import net.minecraft.client.renderer.RenderType;
 import net.minecraft.client.renderer.WorldRenderer;
+import net.minecraft.entity.Entity;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.util.math.BlockRayTraceResult;
-import net.minecraft.util.math.RayTraceResult;
-import net.minecraft.util.math.Vec3d;
 import net.minecraft.util.math.shapes.VoxelShape;
+import net.minecraft.util.math.vector.Matrix4f;
+import net.minecraft.util.math.vector.Vector3d;
 import net.minecraft.world.World;
 import net.minecraftforge.api.distmarker.Dist;
-import net.minecraftforge.client.event.DrawBlockHighlightEvent;
+import net.minecraftforge.client.event.DrawHighlightEvent;
 import net.minecraftforge.eventbus.api.SubscribeEvent;
 import net.minecraftforge.fml.common.Mod;
-import org.lwjgl.opengl.GL11;
 
 @Mod.EventBusSubscriber( modid = ComputerCraft.MOD_ID, value = Dist.CLIENT )
 public final class CableHighlightRenderer
@@ -37,14 +39,12 @@ public final class CableHighlightRenderer
      * Draw an outline for a specific part of a cable "Multipart".
      *
      * @param event The event to observe
-     * @see WorldRenderer#drawSelectionBox(ActiveRenderInfo, RayTraceResult, int)
+     * @see WorldRenderer#drawSelectionBox(MatrixStack, IVertexBuilder, Entity, double, double, double, BlockPos, BlockState)
      */
     @SubscribeEvent
-    public static void drawHighlight( DrawBlockHighlightEvent event )
+    public static void drawHighlight( DrawHighlightEvent.HighlightBlock event )
     {
-        if( event.getTarget().getType() != RayTraceResult.Type.BLOCK ) return;
-
-        BlockRayTraceResult hit = (BlockRayTraceResult) event.getTarget();
+        BlockRayTraceResult hit = event.getTarget();
         BlockPos pos = hit.getPos();
         World world = event.getInfo().getRenderViewEntity().getEntityWorld();
         ActiveRenderInfo info = event.getInfo();
@@ -52,38 +52,29 @@ public final class CableHighlightRenderer
         BlockState state = world.getBlockState( pos );
 
         // We only care about instances with both cable and modem.
-        if( state.getBlock() != ComputerCraft.Blocks.cable || state.get( BlockCable.MODEM ).getFacing() == null || !state.get( BlockCable.CABLE ) )
+        if( state.getBlock() != Registry.ModBlocks.CABLE.get() || state.get( BlockCable.MODEM ).getFacing() == null || !state.get( BlockCable.CABLE ) )
         {
             return;
         }
 
         event.setCanceled( true );
 
-        Minecraft mc = Minecraft.getInstance();
-
-        GlStateManager.enableBlend();
-        GlStateManager.blendFuncSeparate( GlStateManager.SourceFactor.SRC_ALPHA, GlStateManager.DestFactor.ONE_MINUS_SRC_ALPHA, GlStateManager.SourceFactor.ONE, GlStateManager.DestFactor.ZERO );
-        GlStateManager.lineWidth( Math.max( 2.5F, mc.mainWindow.getFramebufferWidth() / 1920.0F * 2.5F ) );
-        GlStateManager.disableTexture();
-        GlStateManager.depthMask( false );
-        GlStateManager.matrixMode( GL11.GL_PROJECTION );
-        GlStateManager.pushMatrix();
-        GlStateManager.scalef( 1.0F, 1.0F, 0.999F );
-
         VoxelShape shape = WorldUtil.isVecInside( CableShapes.getModemShape( state ), hit.getHitVec().subtract( pos.getX(), pos.getY(), pos.getZ() ) )
             ? CableShapes.getModemShape( state )
             : CableShapes.getCableShape( state );
 
-        Vec3d cameraPos = info.getProjectedView();
-        WorldRenderer.drawShape(
-            shape, pos.getX() - cameraPos.getX(), pos.getY() - cameraPos.getY(), pos.getZ() - cameraPos.getZ(),
-            0.0F, 0.0F, 0.0F, 0.4F
-        );
+        Vector3d cameraPos = info.getProjectedView();
+        double xOffset = pos.getX() - cameraPos.getX();
+        double yOffset = pos.getY() - cameraPos.getY();
+        double zOffset = pos.getZ() - cameraPos.getZ();
 
-        GlStateManager.popMatrix();
-        GlStateManager.matrixMode( GL11.GL_MODELVIEW );
-        GlStateManager.depthMask( true );
-        GlStateManager.enableTexture();
-        GlStateManager.disableBlend();
+        IVertexBuilder buffer = event.getBuffers().getBuffer( RenderType.getLines() );
+        Matrix4f matrix4f = event.getMatrix().getLast().getMatrix();
+        shape.forEachEdge( ( x1, y1, z1, x2, y2, z2 ) -> {
+            buffer.pos( matrix4f, (float) (x1 + xOffset), (float) (y1 + yOffset), (float) (z1 + zOffset) )
+                .color( 0, 0, 0, 0.4f ).endVertex();
+            buffer.pos( matrix4f, (float) (x2 + xOffset), (float) (y2 + yOffset), (float) (z2 + zOffset) )
+                .color( 0, 0, 0, 0.4f ).endVertex();
+        } );
     }
 }

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

@@ -0,0 +1,175 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2020. 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.IVertexBuilder;
+import dan200.computercraft.ComputerCraft;
+import dan200.computercraft.shared.computer.core.ComputerFamily;
+import net.minecraft.client.renderer.BufferBuilder;
+import net.minecraft.client.renderer.Tessellator;
+import net.minecraft.client.renderer.vertex.DefaultVertexFormats;
+import net.minecraft.util.ResourceLocation;
+import net.minecraft.util.math.vector.Matrix4f;
+import org.lwjgl.opengl.GL11;
+
+import javax.annotation.Nonnull;
+
+public class ComputerBorderRenderer
+{
+    public static final ResourceLocation BACKGROUND_NORMAL = new ResourceLocation( ComputerCraft.MOD_ID, "textures/gui/corners_normal.png" );
+    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 int CORNER_TOP_Y = 28;
+    private static final int CORNER_BOTTOM_Y = CORNER_TOP_Y + BORDER;
+    private static final int CORNER_LEFT_X = BORDER;
+    private static final int CORNER_RIGHT_X = CORNER_LEFT_X + BORDER;
+    private static final int BORDER_RIGHT_X = 36;
+    private static final int GAP = 4;
+
+    private static final float TEX_SCALE = 1 / 256.0f;
+
+    private final Matrix4f transform;
+    private final IVertexBuilder builder;
+    private final int z;
+    private final float r, g, b;
+
+    public ComputerBorderRenderer( Matrix4f transform, IVertexBuilder builder, int z, float r, float g, float b )
+    {
+        this.transform = transform;
+        this.builder = builder;
+        this.z = z;
+        this.r = r;
+        this.g = g;
+        this.b = b;
+    }
+
+
+    @Nonnull
+    public static ResourceLocation getTexture( @Nonnull ComputerFamily family )
+    {
+        switch( family )
+        {
+            case NORMAL:
+            default:
+                return BACKGROUND_NORMAL;
+            case ADVANCED:
+                return BACKGROUND_ADVANCED;
+            case COMMAND:
+                return BACKGROUND_COMMAND;
+        }
+    }
+
+    public static void render( int x, int y, int z, int width, int height )
+    {
+        Tessellator tessellator = Tessellator.getInstance();
+        BufferBuilder buffer = tessellator.getBuffer();
+        buffer.begin( GL11.GL_QUADS, DefaultVertexFormats.POSITION_COLOR_TEX );
+
+        render( IDENTITY, buffer, x, y, z, width, height );
+
+        RenderSystem.enableAlphaTest();
+        tessellator.draw();
+    }
+
+    public static void render( Matrix4f transform, IVertexBuilder buffer, int x, int y, int z, int width, int height )
+    {
+        render( transform, buffer, x, y, z, width, height, 1, 1, 1 );
+    }
+
+    public static void render( Matrix4f transform, IVertexBuilder buffer, int x, int y, int z, int width, int height, float r, float g, float b )
+    {
+        render( transform, buffer, x, y, z, width, height, 0, r, g, b );
+    }
+
+    public static void render( Matrix4f transform, IVertexBuilder buffer, int x, int y, int z, int width, int height, int borderHeight, float r, float g, float b )
+    {
+        new ComputerBorderRenderer( transform, buffer, z, r, g, b ).doRender( x, y, width, height, borderHeight );
+    }
+
+    public void doRender( int x, int y, int width, int height, int bottomHeight )
+    {
+        int endX = x + width;
+        int endY = y + height;
+
+        // Vertical bars
+        renderLine( x - BORDER, y, 0, CORNER_TOP_Y, BORDER, endY - y );
+        renderLine( endX, y, BORDER_RIGHT_X, CORNER_TOP_Y, BORDER, endY - y );
+
+        // Top bar
+        renderLine( x, y - BORDER, 0, 0, endX - x, BORDER );
+        renderCorner( x - BORDER, y - BORDER, CORNER_LEFT_X, CORNER_TOP_Y );
+        renderCorner( endX, y - BORDER, CORNER_RIGHT_X, CORNER_TOP_Y );
+
+        // Bottom bar. We allow for drawing a stretched version, which allows for additional elements (such as the
+        // pocket computer's lights).
+        if( bottomHeight <= 0 )
+        {
+            renderLine( x, endY, 0, BORDER, endX - x, BORDER );
+            renderCorner( x - BORDER, endY, CORNER_LEFT_X, CORNER_BOTTOM_Y );
+            renderCorner( endX, endY, CORNER_RIGHT_X, CORNER_BOTTOM_Y );
+        }
+        else
+        {
+            // Bottom left, middle, right. We do this in three portions: the top inner corners, an extended region for
+            // lights, and then the bottom outer corners.
+            renderTexture( x - BORDER, endY, CORNER_LEFT_X, CORNER_BOTTOM_Y, BORDER, BORDER / 2 );
+            renderTexture( x, endY, 0, BORDER, width, BORDER / 2, BORDER, BORDER / 2 );
+            renderTexture( endX, endY, CORNER_RIGHT_X, CORNER_BOTTOM_Y, BORDER, BORDER / 2 );
+
+            renderTexture( x - BORDER, endY + BORDER / 2, CORNER_LEFT_X, CORNER_BOTTOM_Y + GAP, BORDER, bottomHeight, BORDER, GAP );
+            renderTexture( x, endY + BORDER / 2, 0, BORDER + GAP, width, bottomHeight, BORDER, GAP );
+            renderTexture( endX, endY + BORDER / 2, CORNER_RIGHT_X, CORNER_BOTTOM_Y + GAP, BORDER, bottomHeight, BORDER, GAP );
+
+            renderTexture( x - BORDER, endY + bottomHeight + BORDER / 2, CORNER_LEFT_X, CORNER_BOTTOM_Y + BORDER / 2, BORDER, BORDER / 2 );
+            renderTexture( x, endY + bottomHeight + BORDER / 2, 0, BORDER + BORDER / 2, width, BORDER / 2 );
+            renderTexture( endX, endY + bottomHeight + BORDER / 2, CORNER_RIGHT_X, CORNER_BOTTOM_Y + BORDER / 2, BORDER, BORDER / 2 );
+        }
+    }
+
+    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 );
+    }
+
+    private void renderTexture( int x, int y, int u, int v, int width, int height, int textureWidth, int textureHeight )
+    {
+        builder.pos( transform, x, y + height, z ).color( r, g, b, 1.0f ).tex( u * TEX_SCALE, (v + textureHeight) * TEX_SCALE ).endVertex();
+        builder.pos( transform, x + width, y + height, z ).color( r, g, b, 1.0f ).tex( (u + textureWidth) * TEX_SCALE, (v + textureHeight) * TEX_SCALE ).endVertex();
+        builder.pos( transform, x + width, y, z ).color( r, g, b, 1.0f ).tex( (u + textureWidth) * TEX_SCALE, v * TEX_SCALE ).endVertex();
+        builder.pos( transform, x, y, z ).color( r, g, b, 1.0f ).tex( u * TEX_SCALE, v * TEX_SCALE ).endVertex();
+    }
+}

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

@@ -5,113 +5,135 @@
  */
 package dan200.computercraft.client.render;
 
-import com.mojang.blaze3d.platform.GlStateManager;
+import com.mojang.blaze3d.matrix.MatrixStack;
 import net.minecraft.client.Minecraft;
+import net.minecraft.client.entity.player.AbstractClientPlayerEntity;
 import net.minecraft.client.renderer.FirstPersonRenderer;
+import net.minecraft.client.renderer.IRenderTypeBuffer;
 import net.minecraft.entity.player.PlayerEntity;
 import net.minecraft.item.ItemStack;
 import net.minecraft.util.Hand;
 import net.minecraft.util.HandSide;
 import net.minecraft.util.math.MathHelper;
+import net.minecraft.util.math.vector.Vector3f;
 
 public abstract class ItemMapLikeRenderer
 {
     /**
      * The main rendering method for the item.
      *
-     * @param stack The stack to render
-     * @see FirstPersonRenderer#renderMapFirstPerson(ItemStack)
+     * @param transform The matrix transformation stack
+     * @param render    The buffer to render to
+     * @param stack     The stack to render
+     * @see FirstPersonRenderer#renderItemInFirstPerson(AbstractClientPlayerEntity, float, float, Hand, float, ItemStack, float, MatrixStack, IRenderTypeBuffer, int)
      */
-    protected abstract void renderItem( ItemStack stack );
+    protected abstract void renderItem( MatrixStack transform, IRenderTypeBuffer render, ItemStack stack );
 
-    protected void renderItemFirstPerson( Hand hand, float pitch, float equipProgress, float swingProgress, ItemStack stack )
+    protected void renderItemFirstPerson( MatrixStack transform, IRenderTypeBuffer render, int lightTexture, Hand hand, float pitch, float equipProgress, float swingProgress, ItemStack stack )
     {
         PlayerEntity player = Minecraft.getInstance().player;
 
-        GlStateManager.pushMatrix();
+        transform.push();
         if( hand == Hand.MAIN_HAND && player.getHeldItemOffhand().isEmpty() )
         {
-            renderItemFirstPersonCenter( pitch, equipProgress, swingProgress, stack );
+            renderItemFirstPersonCenter( transform, render, lightTexture, pitch, equipProgress, swingProgress, stack );
         }
         else
         {
             renderItemFirstPersonSide(
+                transform, render, lightTexture,
                 hand == Hand.MAIN_HAND ? player.getPrimaryHand() : player.getPrimaryHand().opposite(),
                 equipProgress, swingProgress, stack
             );
         }
-        GlStateManager.popMatrix();
+        transform.pop();
     }
 
     /**
      * 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 FirstPersonRenderer#renderMapFirstPersonSide(float, HandSide, float, ItemStack)
+     * @see FirstPersonRenderer#renderMapFirstPersonSide(MatrixStack, IRenderTypeBuffer, int, float, HandSide, float, ItemStack)
      */
-    private void renderItemFirstPersonSide( HandSide side, float equipProgress, float swingProgress, ItemStack stack )
+    private void renderItemFirstPersonSide( MatrixStack transform, IRenderTypeBuffer render, int combinedLight, HandSide side, float equipProgress, float swingProgress, ItemStack stack )
     {
         Minecraft minecraft = Minecraft.getInstance();
         float offset = side == HandSide.RIGHT ? 1f : -1f;
-        GlStateManager.translatef( offset * 0.125f, -0.125f, 0f );
+        transform.translate( offset * 0.125f, -0.125f, 0f );
 
         // If the player is not invisible then render a single arm
         if( !minecraft.player.isInvisible() )
         {
-            GlStateManager.pushMatrix();
-            GlStateManager.rotatef( offset * 10f, 0f, 0f, 1f );
-            minecraft.getFirstPersonRenderer().renderArmFirstPerson( equipProgress, swingProgress, side );
-            GlStateManager.popMatrix();
+            transform.push();
+            transform.rotate( Vector3f.ZP.rotationDegrees( offset * 10f ) );
+            minecraft.getFirstPersonRenderer().renderArmFirstPerson( transform, render, combinedLight, equipProgress, swingProgress, side );
+            transform.pop();
         }
 
         // Setup the appropriate transformations. This is just copied from the
         // corresponding method in ItemRenderer.
-        GlStateManager.pushMatrix();
-        GlStateManager.translatef( offset * 0.51f, -0.08f + equipProgress * -1.2f, -0.75f );
+        transform.push();
+        transform.translate( offset * 0.51f, -0.08f + equipProgress * -1.2f, -0.75f );
         float f1 = MathHelper.sqrt( swingProgress );
         float f2 = MathHelper.sin( f1 * (float) Math.PI );
         float f3 = -0.5f * f2;
         float f4 = 0.4f * MathHelper.sin( f1 * ((float) Math.PI * 2f) );
         float f5 = -0.3f * MathHelper.sin( swingProgress * (float) Math.PI );
-        GlStateManager.translatef( offset * f3, f4 - 0.3f * f2, f5 );
-        GlStateManager.rotatef( f2 * -45f, 1f, 0f, 0f );
-        GlStateManager.rotatef( offset * f2 * -30f, 0f, 1f, 0f );
+        transform.translate( offset * f3, f4 - 0.3f * f2, f5 );
+        transform.rotate( Vector3f.XP.rotationDegrees( f2 * -45f ) );
+        transform.rotate( Vector3f.YP.rotationDegrees( offset * f2 * -30f ) );
 
-        renderItem( stack );
+        renderItem( transform, render, stack );
 
-        GlStateManager.popMatrix();
+        transform.pop();
     }
 
     /**
      * Render an item in the middle of the screen.
      *
+     * @param transform     The matrix transformation stack
+     * @param render        The buffer to render to
+     * @param combinedLight The current light level
      * @param pitch         The pitch of the player
      * @param equipProgress The equip progress of this item
      * @param swingProgress The swing progress of this item
      * @param stack         The stack to render
-     * @see FirstPersonRenderer#renderMapFirstPerson(float, float, float)
+     * @see FirstPersonRenderer#renderMapFirstPerson(MatrixStack, IRenderTypeBuffer, int, float, float, float)
      */
-    private void renderItemFirstPersonCenter( float pitch, float equipProgress, float swingProgress, ItemStack stack )
+    private void renderItemFirstPersonCenter( MatrixStack transform, IRenderTypeBuffer render, int combinedLight, float pitch, float equipProgress, float swingProgress, ItemStack stack )
     {
-        FirstPersonRenderer renderer = Minecraft.getInstance().getFirstPersonRenderer();
+        Minecraft minecraft = Minecraft.getInstance();
+        FirstPersonRenderer renderer = minecraft.getFirstPersonRenderer();
 
         // Setup the appropriate transformations. This is just copied from the
         // corresponding method in ItemRenderer.
         float swingRt = MathHelper.sqrt( swingProgress );
         float tX = -0.2f * MathHelper.sin( swingProgress * (float) Math.PI );
         float tZ = -0.4f * MathHelper.sin( swingRt * (float) Math.PI );
-        GlStateManager.translatef( 0f, -tX / 2f, tZ );
-        float pitchAngle = renderer.getMapAngleFromPitch( pitch );
-        GlStateManager.translatef( 0f, 0.04f + equipProgress * -1.2f + pitchAngle * -0.5f, -0.72f );
-        GlStateManager.rotatef( pitchAngle * -85f, 1f, 0f, 0f );
-        renderer.renderArms();
-        float rX = MathHelper.sin( swingRt * (float) Math.PI );
-        GlStateManager.rotatef( rX * 20f, 1f, 0f, 0f );
-        GlStateManager.scalef( 2f, 2f, 2f );
+        transform.translate( 0, -tX / 2, tZ );
 
-        renderItem( stack );
+        float pitchAngle = renderer.getMapAngleFromPitch( pitch );
+        transform.translate( 0, 0.04F + equipProgress * -1.2f + pitchAngle * -0.5f, -0.72f );
+        transform.rotate( Vector3f.XP.rotationDegrees( pitchAngle * -85.0f ) );
+        if( !minecraft.player.isInvisible() )
+        {
+            transform.push();
+            transform.rotate( Vector3f.YP.rotationDegrees( 90.0F ) );
+            renderer.renderArm( transform, render, combinedLight, HandSide.RIGHT );
+            renderer.renderArm( transform, render, combinedLight, HandSide.LEFT );
+            transform.pop();
+        }
+
+        float rX = MathHelper.sin( swingRt * (float) Math.PI );
+        transform.rotate( Vector3f.XP.rotationDegrees( rX * 20.0F ) );
+        transform.scale( 2.0F, 2.0F, 2.0F );
+
+        renderItem( transform, render, stack );
     }
 }

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

@@ -5,7 +5,8 @@
  */
 package dan200.computercraft.client.render;
 
-import com.mojang.blaze3d.platform.GlStateManager;
+import com.mojang.blaze3d.matrix.MatrixStack;
+import com.mojang.blaze3d.systems.RenderSystem;
 import dan200.computercraft.ComputerCraft;
 import dan200.computercraft.client.gui.FixedWidthFontRenderer;
 import dan200.computercraft.core.terminal.Terminal;
@@ -15,18 +16,22 @@ import dan200.computercraft.shared.pocket.items.ItemPocketComputer;
 import dan200.computercraft.shared.util.Colour;
 import net.minecraft.client.Minecraft;
 import net.minecraft.client.renderer.BufferBuilder;
+import net.minecraft.client.renderer.IRenderTypeBuffer;
 import net.minecraft.client.renderer.Tessellator;
 import net.minecraft.client.renderer.vertex.DefaultVertexFormats;
 import net.minecraft.item.ItemStack;
+import net.minecraft.util.math.vector.Matrix4f;
+import net.minecraft.util.math.vector.Vector3f;
 import net.minecraftforge.api.distmarker.Dist;
-import net.minecraftforge.client.event.RenderSpecificHandEvent;
+import net.minecraftforge.client.event.RenderHandEvent;
 import net.minecraftforge.eventbus.api.SubscribeEvent;
 import net.minecraftforge.fml.common.Mod;
 import org.lwjgl.opengl.GL11;
 
 import static dan200.computercraft.client.gui.FixedWidthFontRenderer.FONT_HEIGHT;
 import static dan200.computercraft.client.gui.FixedWidthFontRenderer.FONT_WIDTH;
-import static dan200.computercraft.client.gui.GuiComputer.*;
+import static dan200.computercraft.client.render.ComputerBorderRenderer.BORDER;
+import static dan200.computercraft.client.render.ComputerBorderRenderer.MARGIN;
 
 /**
  * Emulates map rendering for pocket computers.
@@ -34,8 +39,6 @@ import static dan200.computercraft.client.gui.GuiComputer.*;
 @Mod.EventBusSubscriber( modid = ComputerCraft.MOD_ID, value = Dist.CLIENT )
 public final class ItemPocketRenderer extends ItemMapLikeRenderer
 {
-    private static final int MARGIN = 2;
-    private static final int FRAME = 12;
     private static final int LIGHT_HEIGHT = 8;
 
     private static final ItemPocketRenderer INSTANCE = new ItemPocketRenderer();
@@ -45,17 +48,20 @@ public final class ItemPocketRenderer extends ItemMapLikeRenderer
     }
 
     @SubscribeEvent
-    public static void renderItem( RenderSpecificHandEvent event )
+    public static void onRenderInHand( RenderHandEvent event )
     {
         ItemStack stack = event.getItemStack();
         if( !(stack.getItem() instanceof ItemPocketComputer) ) return;
 
         event.setCanceled( true );
-        INSTANCE.renderItemFirstPerson( event.getHand(), event.getInterpolatedPitch(), event.getEquipProgress(), event.getSwingProgress(), event.getItemStack() );
+        INSTANCE.renderItemFirstPerson(
+            event.getMatrixStack(), event.getBuffers(), event.getLight(),
+            event.getHand(), event.getInterpolatedPitch(), event.getEquipProgress(), event.getSwingProgress(), event.getItemStack()
+        );
     }
 
     @Override
-    protected void renderItem( ItemStack stack )
+    protected void renderItem( MatrixStack transform, IRenderTypeBuffer render, ItemStack stack )
     {
         ClientComputer computer = ItemPocketComputer.createClientComputer( stack );
         Terminal terminal = computer == null ? null : computer.getTerminal();
@@ -63,8 +69,8 @@ public final class ItemPocketRenderer extends ItemMapLikeRenderer
         int termWidth, termHeight;
         if( terminal == null )
         {
-            termWidth = ComputerCraft.terminalWidth_pocketComputer;
-            termHeight = ComputerCraft.terminalHeight_pocketComputer;
+            termWidth = ComputerCraft.pocketTermWidth;
+            termHeight = ComputerCraft.pocketTermHeight;
         }
         else
         {
@@ -77,51 +83,44 @@ public final class ItemPocketRenderer extends ItemMapLikeRenderer
 
         // Setup various transformations. Note that these are partially adapted from the corresponding method
         // in ItemRenderer
-        GlStateManager.pushMatrix();
+        transform.push();
+        transform.rotate( Vector3f.YP.rotationDegrees( 180f ) );
+        transform.rotate( Vector3f.ZP.rotationDegrees( 180f ) );
+        transform.scale( 0.5f, 0.5f, 0.5f );
 
-        GlStateManager.disableLighting();
-        GlStateManager.disableDepthTest();
-
-        GlStateManager.rotatef( 180f, 0f, 1f, 0f );
-        GlStateManager.rotatef( 180f, 0f, 0f, 1f );
-        GlStateManager.scalef( 0.5f, 0.5f, 0.5f );
-
-        double scale = 0.75 / Math.max( width + FRAME * 2, height + FRAME * 2 + LIGHT_HEIGHT );
-        GlStateManager.scaled( scale, scale, 0 );
-        GlStateManager.translated( -0.5 * width, -0.5 * height, 0 );
+        float scale = 0.75f / Math.max( width + BORDER * 2, height + BORDER * 2 + LIGHT_HEIGHT );
+        transform.scale( scale, scale, 0 );
+        transform.translate( -0.5 * width, -0.5 * height, 0 );
 
         // Render the main frame
         ItemPocketComputer item = (ItemPocketComputer) stack.getItem();
         ComputerFamily family = item.getFamily();
         int frameColour = item.getColour( stack );
-        renderFrame( family, frameColour, width, height );
+
+        Matrix4f matrix = transform.getLast().getMatrix();
+        renderFrame( matrix, family, frameColour, width, height );
 
         // Render the light
         int lightColour = ItemPocketComputer.getLightState( stack );
-        if( lightColour == -1 ) lightColour = Colour.Black.getHex();
-        renderLight( lightColour, width, height );
+        if( lightColour == -1 ) lightColour = Colour.BLACK.getHex();
+        renderLight( matrix, lightColour, width, height );
 
         if( computer != null && terminal != null )
         {
-            FixedWidthFontRenderer.drawTerminal( MARGIN, MARGIN, terminal, !computer.isColour(), MARGIN, MARGIN, MARGIN, MARGIN );
+            FixedWidthFontRenderer.drawTerminal( matrix, MARGIN, MARGIN, terminal, !computer.isColour(), MARGIN, MARGIN, MARGIN, MARGIN );
         }
         else
         {
-            FixedWidthFontRenderer.drawEmptyTerminal( 0, 0, width, height );
+            FixedWidthFontRenderer.drawEmptyTerminal( matrix, 0, 0, width, height );
         }
 
-        GlStateManager.enableDepthTest();
-        GlStateManager.enableLighting();
-        GlStateManager.popMatrix();
+        transform.pop();
     }
 
-    private static void renderFrame( ComputerFamily family, int colour, int width, int height )
+    private static void renderFrame( Matrix4f transform, ComputerFamily family, int colour, int width, int height )
     {
-
-        Minecraft.getInstance().getTextureManager().bindTexture( colour != -1
-            ? BACKGROUND_COLOUR
-            : family == ComputerFamily.Normal ? BACKGROUND_NORMAL : BACKGROUND_ADVANCED
-        );
+        Minecraft.getInstance().getTextureManager()
+            .bindTexture( colour != -1 ? ComputerBorderRenderer.BACKGROUND_COLOUR : ComputerBorderRenderer.getTexture( family ) );
 
         float r = ((colour >>> 16) & 0xFF) / 255.0f;
         float g = ((colour >>> 8) & 0xFF) / 255.0f;
@@ -129,38 +128,17 @@ public final class ItemPocketRenderer extends ItemMapLikeRenderer
 
         Tessellator tessellator = Tessellator.getInstance();
         BufferBuilder buffer = tessellator.getBuffer();
-        buffer.begin( GL11.GL_QUADS, DefaultVertexFormats.POSITION_TEX_COLOR );
+        buffer.begin( GL11.GL_QUADS, DefaultVertexFormats.POSITION_COLOR_TEX );
 
-        // Top left, middle, right
-        renderTexture( buffer, -FRAME, -FRAME, 12, 28, FRAME, FRAME, r, g, b );
-        renderTexture( buffer, 0, -FRAME, 0, 0, width, FRAME, r, g, b );
-        renderTexture( buffer, width, -FRAME, 24, 28, FRAME, FRAME, r, g, b );
-
-        // Left and bright border
-        renderTexture( buffer, -FRAME, 0, 0, 28, FRAME, height, r, g, b );
-        renderTexture( buffer, width, 0, 36, 28, FRAME, height, r, g, b );
-
-        // Bottom left, middle, right. We do this in three portions: the top inner corners, an extended region for
-        // lights, and then the bottom outer corners.
-        renderTexture( buffer, -FRAME, height, 12, 40, FRAME, FRAME / 2, r, g, b );
-        renderTexture( buffer, 0, height, 0, 12, width, FRAME / 2, r, g, b );
-        renderTexture( buffer, width, height, 24, 40, FRAME, FRAME / 2, r, g, b );
-
-        renderTexture( buffer, -FRAME, height + FRAME / 2, 12, 44, FRAME, LIGHT_HEIGHT, FRAME, 4, r, g, b );
-        renderTexture( buffer, 0, height + FRAME / 2, 0, 16, width, LIGHT_HEIGHT, FRAME, 4, r, g, b );
-        renderTexture( buffer, width, height + FRAME / 2, 24, 44, FRAME, LIGHT_HEIGHT, FRAME, 4, r, g, b );
-
-        renderTexture( buffer, -FRAME, height + LIGHT_HEIGHT + FRAME / 2, 12, 40 + FRAME / 2, FRAME, FRAME / 2, r, g, b );
-        renderTexture( buffer, 0, height + LIGHT_HEIGHT + FRAME / 2, 0, 12 + FRAME / 2, width, FRAME / 2, r, g, b );
-        renderTexture( buffer, width, height + LIGHT_HEIGHT + FRAME / 2, 24, 40 + FRAME / 2, FRAME, FRAME / 2, r, g, b );
+        ComputerBorderRenderer.render( transform, buffer, 0, 0, 0, width, height, LIGHT_HEIGHT, r, g, b );
 
         tessellator.draw();
     }
 
-    private static void renderLight( int colour, int width, int height )
+    private static void renderLight( Matrix4f transform, int colour, int width, int height )
     {
-        GlStateManager.enableBlend();
-        GlStateManager.disableTexture();
+        RenderSystem.enableBlend();
+        RenderSystem.disableTexture();
 
         float r = ((colour >>> 16) & 0xFF) / 255.0f;
         float g = ((colour >>> 8) & 0xFF) / 255.0f;
@@ -169,26 +147,12 @@ public final class ItemPocketRenderer extends ItemMapLikeRenderer
         Tessellator tessellator = Tessellator.getInstance();
         BufferBuilder buffer = tessellator.getBuffer();
         buffer.begin( GL11.GL_QUADS, DefaultVertexFormats.POSITION_COLOR );
-        buffer.pos( width - LIGHT_HEIGHT * 2, height + LIGHT_HEIGHT + FRAME / 2.0f, 0.0D ).color( r, g, b, 1.0f ).endVertex();
-        buffer.pos( width, height + LIGHT_HEIGHT + FRAME / 2.0f, 0.0D ).color( r, g, b, 1.0f ).endVertex();
-        buffer.pos( width, height + FRAME / 2.0f, 0.0D ).color( r, g, b, 1.0f ).endVertex();
-        buffer.pos( width - LIGHT_HEIGHT * 2, height + FRAME / 2.0f, 0.0D ).color( r, g, b, 1.0f ).endVertex();
+        buffer.pos( transform, width - LIGHT_HEIGHT * 2, height + LIGHT_HEIGHT + BORDER / 2.0f, 0 ).color( r, g, b, 1.0f ).endVertex();
+        buffer.pos( transform, width, height + LIGHT_HEIGHT + BORDER / 2.0f, 0 ).color( r, g, b, 1.0f ).endVertex();
+        buffer.pos( transform, width, height + BORDER / 2.0f, 0 ).color( r, g, b, 1.0f ).endVertex();
+        buffer.pos( transform, width - LIGHT_HEIGHT * 2, height + BORDER / 2.0f, 0 ).color( r, g, b, 1.0f ).endVertex();
 
         tessellator.draw();
-        GlStateManager.enableTexture();
-    }
-
-    private static void renderTexture( BufferBuilder builder, int x, int y, int textureX, int textureY, int width, int height, float r, float g, float b )
-    {
-        renderTexture( builder, x, y, textureX, textureY, width, height, width, height, r, g, b );
-    }
-
-    private static void renderTexture( BufferBuilder builder, int x, int y, int textureX, int textureY, int width, int height, int textureWidth, int textureHeight, float r, float g, float b )
-    {
-        float scale = 1 / 255.0f;
-        builder.pos( x, y + height, 0 ).tex( textureX * scale, (textureY + textureHeight) * scale ).color( r, g, b, 1.0f ).endVertex();
-        builder.pos( x + width, y + height, 0 ).tex( (textureX + textureWidth) * scale, (textureY + textureHeight) * scale ).color( r, g, b, 1.0f ).endVertex();
-        builder.pos( x + width, y, 0 ).tex( (textureX + textureWidth) * scale, textureY * scale ).color( r, g, b, 1.0f ).endVertex();
-        builder.pos( x, y, 0 ).tex( textureX * scale, textureY * scale ).color( r, g, b, 1.0f ).endVertex();
+        RenderSystem.enableTexture();
     }
 }

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

@@ -5,13 +5,16 @@
  */
 package dan200.computercraft.client.render;
 
-import com.mojang.blaze3d.platform.GlStateManager;
+import com.mojang.blaze3d.matrix.MatrixStack;
 import dan200.computercraft.ComputerCraft;
 import dan200.computercraft.shared.media.items.ItemPrintout;
+import net.minecraft.client.renderer.IRenderTypeBuffer;
 import net.minecraft.item.ItemStack;
+import net.minecraft.util.math.vector.Matrix4f;
+import net.minecraft.util.math.vector.Vector3f;
 import net.minecraftforge.api.distmarker.Dist;
+import net.minecraftforge.client.event.RenderHandEvent;
 import net.minecraftforge.client.event.RenderItemInFrameEvent;
-import net.minecraftforge.client.event.RenderSpecificHandEvent;
 import net.minecraftforge.eventbus.api.SubscribeEvent;
 import net.minecraftforge.fml.common.Mod;
 
@@ -34,30 +37,26 @@ public final class ItemPrintoutRenderer extends ItemMapLikeRenderer
     }
 
     @SubscribeEvent
-    public static void onRenderInHand( RenderSpecificHandEvent event )
+    public static void onRenderInHand( RenderHandEvent event )
     {
         ItemStack stack = event.getItemStack();
         if( !(stack.getItem() instanceof ItemPrintout) ) return;
 
         event.setCanceled( true );
-        INSTANCE.renderItemFirstPerson( event.getHand(), event.getInterpolatedPitch(), event.getEquipProgress(), event.getSwingProgress(), event.getItemStack() );
+        INSTANCE.renderItemFirstPerson(
+            event.getMatrixStack(), event.getBuffers(), event.getLight(),
+            event.getHand(), event.getInterpolatedPitch(), event.getEquipProgress(), event.getSwingProgress(), event.getItemStack()
+        );
     }
 
     @Override
-    protected void renderItem( ItemStack stack )
+    protected void renderItem( MatrixStack transform, IRenderTypeBuffer render, ItemStack stack )
     {
-        // Setup various transformations. Note that these are partially adapated from the corresponding method
-        // in FirstPersonRenderer.renderFirstPersonMap
-        GlStateManager.disableLighting();
+        transform.rotate( Vector3f.XP.rotationDegrees( 180f ) );
+        transform.scale( 0.42f, 0.42f, -0.42f );
+        transform.translate( -0.5f, -0.48f, 0.0f );
 
-        GlStateManager.rotatef( 180f, 0f, 1f, 0f );
-        GlStateManager.rotatef( 180f, 0f, 0f, 1f );
-        GlStateManager.scalef( 0.42f, 0.42f, -0.42f );
-        GlStateManager.translatef( -0.5f, -0.48f, 0.0f );
-
-        drawPrintout( stack );
-
-        GlStateManager.enableLighting();
+        drawPrintout( transform, render, stack );
     }
 
     @SubscribeEvent
@@ -65,24 +64,20 @@ public final class ItemPrintoutRenderer extends ItemMapLikeRenderer
     {
         ItemStack stack = event.getItem();
         if( !(stack.getItem() instanceof ItemPrintout) ) return;
-
         event.setCanceled( true );
 
-        GlStateManager.disableLighting();
+        MatrixStack transform = event.getMatrix();
 
         // Move a little bit forward to ensure we're not clipping with the frame
-        GlStateManager.translatef( 0.0f, 0.0f, -0.001f );
-        GlStateManager.rotatef( 180f, 0f, 0f, 1f );
-        GlStateManager.scalef( 0.95f, 0.95f, -0.95f );
-        GlStateManager.translatef( -0.5f, -0.5f, 0.0f );
+        transform.translate( 0.0f, 0.0f, -0.001f );
+        transform.rotate( Vector3f.ZP.rotationDegrees( 180f ) );
+        transform.scale( 0.95f, 0.95f, -0.95f );
+        transform.translate( -0.5f, -0.5f, 0.0f );
 
-        drawPrintout( stack );
-
-        GlStateManager.enableLighting();
-        GlStateManager.disableBlend();
+        drawPrintout( transform, event.getBuffers(), stack );
     }
 
-    private static void drawPrintout( ItemStack stack )
+    private static void drawPrintout( MatrixStack transform, IRenderTypeBuffer render, ItemStack stack )
     {
         int pages = ItemPrintout.getPageCount( stack );
         boolean book = ((ItemPrintout) stack.getItem()).getType() == ItemPrintout.Type.BOOK;
@@ -105,11 +100,14 @@ public final class ItemPrintoutRenderer extends ItemMapLikeRenderer
         double max = Math.max( visualHeight, visualWidth );
 
         // Scale the printout to fit correctly.
-        double scale = 1.0 / max;
-        GlStateManager.scaled( scale, scale, scale );
-        GlStateManager.translated( (max - width) / 2.0, (max - height) / 2.0, 0.0 );
+        float scale = (float) (1.0 / max);
+        transform.scale( scale, scale, scale );
+        transform.translate( (max - width) / 2.0, (max - height) / 2.0, 0.0 );
 
-        drawBorder( 0, 0, -0.01, 0, pages, book );
-        drawText( X_TEXT_MARGIN, Y_TEXT_MARGIN, 0, ItemPrintout.getText( stack ), ItemPrintout.getColours( stack ) );
+        Matrix4f matrix = transform.getLast().getMatrix();
+        drawBorder( matrix, render, 0, 0, -0.01f, 0, pages, book );
+        drawText( matrix, render,
+            X_TEXT_MARGIN, Y_TEXT_MARGIN, 0, ItemPrintout.getText( stack ), ItemPrintout.getColours( stack )
+        );
     }
 }

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

@@ -1,269 +0,0 @@
-/*
- * This file is part of ComputerCraft - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2020. Do not distribute without permission.
- * Send enquiries to dratcliffe@gmail.com
- */
-package dan200.computercraft.client.render;
-
-import net.minecraft.client.renderer.model.BakedQuad;
-import net.minecraft.client.renderer.texture.TextureAtlasSprite;
-import net.minecraft.client.renderer.vertex.VertexFormat;
-import net.minecraft.util.Direction;
-import net.minecraftforge.client.model.pipeline.IVertexConsumer;
-import net.minecraftforge.client.model.pipeline.LightUtil;
-import net.minecraftforge.client.model.pipeline.VertexTransformer;
-import net.minecraftforge.common.model.TRSRTransformation;
-
-import javax.annotation.Nonnull;
-import javax.vecmath.Matrix4f;
-import javax.vecmath.Point3f;
-import javax.vecmath.Vector3f;
-import java.util.List;
-
-/**
- * Transforms vertices of a model, remaining aware of winding order, and rearranging
- * vertices if needed.
- */
-public final class ModelTransformer
-{
-    private static final Matrix4f identity;
-
-    static
-    {
-        identity = new Matrix4f();
-        identity.setIdentity();
-    }
-
-    private ModelTransformer()
-    {
-    }
-
-    public static void transformQuadsTo( List<BakedQuad> output, List<BakedQuad> input, Matrix4f transform )
-    {
-        if( transform == null || transform.equals( identity ) )
-        {
-            output.addAll( input );
-        }
-        else
-        {
-            Matrix4f normalMatrix = new Matrix4f( transform );
-            normalMatrix.invert();
-            normalMatrix.transpose();
-
-            for( BakedQuad quad : input ) output.add( doTransformQuad( quad, transform, normalMatrix ) );
-        }
-    }
-
-    public static BakedQuad transformQuad( BakedQuad input, Matrix4f transform )
-    {
-        if( transform == null || transform.equals( identity ) ) return input;
-
-        Matrix4f normalMatrix = new Matrix4f( transform );
-        normalMatrix.invert();
-        normalMatrix.transpose();
-        return doTransformQuad( input, transform, normalMatrix );
-    }
-
-    private static BakedQuad doTransformQuad( BakedQuad input, Matrix4f positionMatrix, Matrix4f normalMatrix )
-    {
-
-        BakedQuadBuilder builder = new BakedQuadBuilder( input.getFormat() );
-        NormalAwareTransformer transformer = new NormalAwareTransformer( builder, positionMatrix, normalMatrix );
-        input.pipe( transformer );
-
-        if( transformer.areNormalsInverted() )
-        {
-            builder.swap( 1, 3 );
-            transformer.areNormalsInverted();
-        }
-
-        return builder.build();
-    }
-
-    /**
-     * A vertex transformer that tracks whether the normals have been inverted and so the vertices
-     * should be reordered so backface culling works as expected.
-     */
-    private static class NormalAwareTransformer extends VertexTransformer
-    {
-        private final Matrix4f positionMatrix;
-        private final Matrix4f normalMatrix;
-
-        private int vertexIndex = 0, elementIndex = 0;
-        private final Point3f[] before = new Point3f[4];
-        private final Point3f[] after = new Point3f[4];
-
-        NormalAwareTransformer( IVertexConsumer parent, Matrix4f positionMatrix, Matrix4f normalMatrix )
-        {
-            super( parent );
-            this.positionMatrix = positionMatrix;
-            this.normalMatrix = normalMatrix;
-        }
-
-        @Override
-        public void setQuadOrientation( @Nonnull Direction orientation )
-        {
-            super.setQuadOrientation( orientation == null ? orientation : TRSRTransformation.rotate( positionMatrix, orientation ) );
-        }
-
-        @Override
-        public void put( int element, @Nonnull float... data )
-        {
-            switch( getVertexFormat().getElement( element ).getUsage() )
-            {
-                case POSITION:
-                {
-                    Point3f vec = new Point3f( data );
-                    Point3f newVec = new Point3f();
-                    positionMatrix.transform( vec, newVec );
-
-                    float[] newData = new float[4];
-                    newVec.get( newData );
-                    super.put( element, newData );
-
-
-                    before[vertexIndex] = vec;
-                    after[vertexIndex] = newVec;
-                    break;
-                }
-                case NORMAL:
-                {
-                    Vector3f vec = new Vector3f( data );
-                    normalMatrix.transform( vec );
-
-                    float[] newData = new float[4];
-                    vec.get( newData );
-                    super.put( element, newData );
-                    break;
-                }
-                default:
-                    super.put( element, data );
-                    break;
-            }
-
-            elementIndex++;
-            if( elementIndex == getVertexFormat().getElementCount() )
-            {
-                vertexIndex++;
-                elementIndex = 0;
-            }
-        }
-
-        public boolean areNormalsInverted()
-        {
-            Vector3f temp1 = new Vector3f(), temp2 = new Vector3f();
-            Vector3f crossBefore = new Vector3f(), crossAfter = new Vector3f();
-
-            // Determine what cross product we expect to have
-            temp1.sub( before[1], before[0] );
-            temp2.sub( before[1], before[2] );
-            crossBefore.cross( temp1, temp2 );
-            normalMatrix.transform( crossBefore );
-
-            // And determine what cross product we actually have
-            temp1.sub( after[1], after[0] );
-            temp2.sub( after[1], after[2] );
-            crossAfter.cross( temp1, temp2 );
-
-            // If the angle between expected and actual cross product is greater than
-            // pi/2 radians then we will need to reorder our quads.
-            return Math.abs( crossBefore.angle( crossAfter ) ) >= Math.PI / 2;
-        }
-    }
-
-    /**
-     * A vertex consumer which is capable of building {@link BakedQuad}s.
-     *
-     * Equivalent to {@link net.minecraftforge.client.model.pipeline.UnpackedBakedQuad.Builder} but more memory
-     * efficient.
-     *
-     * This also provides the ability to swap vertices through {@link #swap(int, int)} to allow reordering.
-     */
-    private static final class BakedQuadBuilder implements IVertexConsumer
-    {
-        private final VertexFormat format;
-
-        private final int[] vertexData;
-        private int vertexIndex = 0, elementIndex = 0;
-
-        private Direction orientation;
-        private int quadTint;
-        private boolean diffuse;
-        private TextureAtlasSprite texture;
-
-        private BakedQuadBuilder( VertexFormat format )
-        {
-            this.format = format;
-            vertexData = new int[format.getSize()];
-        }
-
-        @Nonnull
-        @Override
-        public VertexFormat getVertexFormat()
-        {
-            return format;
-        }
-
-        @Override
-        public void setQuadTint( int tint )
-        {
-            quadTint = tint;
-        }
-
-        @Override
-        public void setQuadOrientation( @Nonnull Direction orientation )
-        {
-            this.orientation = orientation;
-        }
-
-        @Override
-        public void setApplyDiffuseLighting( boolean diffuse )
-        {
-            this.diffuse = diffuse;
-        }
-
-        @Override
-        public void setTexture( @Nonnull TextureAtlasSprite texture )
-        {
-            this.texture = texture;
-        }
-
-        @Override
-        public void put( int element, @Nonnull float... data )
-        {
-            LightUtil.pack( data, vertexData, format, vertexIndex, element );
-
-            elementIndex++;
-            if( elementIndex == getVertexFormat().getElementCount() )
-            {
-                vertexIndex++;
-                elementIndex = 0;
-            }
-        }
-
-        public void swap( int a, int b )
-        {
-            int length = vertexData.length / 4;
-            for( int i = 0; i < length; i++ )
-            {
-                int temp = vertexData[a * length + i];
-                vertexData[a * length + i] = vertexData[b * length + i];
-                vertexData[b * length + i] = temp;
-            }
-        }
-
-        public BakedQuad build()
-        {
-            if( elementIndex != 0 || vertexIndex != 4 )
-            {
-                throw new IllegalStateException( "Got an unexpected number of elements/vertices" );
-            }
-            if( texture == null )
-            {
-                throw new IllegalStateException( "Texture has not been set" );
-            }
-
-            return new BakedQuad( vertexData, quadTint, orientation, texture, diffuse, format );
-        }
-    }
-}

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

@@ -5,49 +5,45 @@
  */
 package dan200.computercraft.client.render;
 
-import com.mojang.blaze3d.platform.GlStateManager;
+import com.mojang.blaze3d.matrix.MatrixStack;
+import com.mojang.blaze3d.vertex.IVertexBuilder;
 import dan200.computercraft.ComputerCraft;
 import dan200.computercraft.shared.peripheral.monitor.TileMonitor;
-import net.minecraft.client.Minecraft;
-import net.minecraft.client.renderer.BufferBuilder;
-import net.minecraft.client.renderer.Tessellator;
-import net.minecraft.client.renderer.vertex.DefaultVertexFormats;
+import net.minecraft.client.renderer.RenderType;
 import net.minecraft.tileentity.TileEntity;
 import net.minecraft.util.Direction;
 import net.minecraft.util.math.BlockPos;
-import net.minecraft.util.math.BlockRayTraceResult;
-import net.minecraft.util.math.RayTraceResult;
-import net.minecraft.util.math.Vec3d;
+import net.minecraft.util.math.vector.Matrix4f;
+import net.minecraft.util.math.vector.Vector3d;
 import net.minecraft.world.World;
 import net.minecraftforge.api.distmarker.Dist;
-import net.minecraftforge.client.event.DrawBlockHighlightEvent;
+import net.minecraftforge.client.event.DrawHighlightEvent;
 import net.minecraftforge.eventbus.api.SubscribeEvent;
 import net.minecraftforge.fml.common.Mod;
-import org.lwjgl.opengl.GL11;
 
 import java.util.EnumSet;
 
 import static net.minecraft.util.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.
+ */
 @Mod.EventBusSubscriber( modid = ComputerCraft.MOD_ID, value = Dist.CLIENT )
 public final class MonitorHighlightRenderer
 {
-    private static final float EXPAND = 0.002f;
-
     private MonitorHighlightRenderer()
     {
     }
 
     @SubscribeEvent
-    public static void drawHighlight( DrawBlockHighlightEvent event )
+    public static void drawHighlight( DrawHighlightEvent.HighlightBlock event )
     {
-        if( event.getTarget().getType() != RayTraceResult.Type.BLOCK || event.getInfo().getRenderViewEntity().isSneaking() )
-        {
-            return;
-        }
+        // Preserve normal behaviour when crouching.
+        if( event.getInfo().getRenderViewEntity().isCrouching() ) return;
 
         World world = event.getInfo().getRenderViewEntity().getEntityWorld();
-        BlockPos pos = ((BlockRayTraceResult) event.getTarget()).getPos();
+        BlockPos pos = event.getTarget().getPos();
 
         TileEntity tile = world.getTileEntity( pos );
         if( !(tile instanceof TileMonitor) ) return;
@@ -64,53 +60,37 @@ public final class MonitorHighlightRenderer
         if( monitor.getYIndex() != 0 ) faces.remove( monitor.getDown().getOpposite() );
         if( monitor.getYIndex() != monitor.getHeight() - 1 ) faces.remove( monitor.getDown() );
 
-        GlStateManager.enableBlend();
-        GlStateManager.blendFuncSeparate( GlStateManager.SourceFactor.SRC_ALPHA, GlStateManager.DestFactor.ONE_MINUS_SRC_ALPHA, GlStateManager.SourceFactor.ONE, GlStateManager.DestFactor.ZERO );
-        GlStateManager.lineWidth( Math.max( 2.5F, (float) Minecraft.getInstance().mainWindow.getFramebufferWidth() / 1920.0F * 2.5F ) );
-        GlStateManager.disableTexture();
-        GlStateManager.depthMask( false );
-        GlStateManager.pushMatrix();
-
-        Vec3d cameraPos = event.getInfo().getProjectedView();
-        GlStateManager.translated( pos.getX() - cameraPos.getX(), pos.getY() - cameraPos.getY(), pos.getZ() - cameraPos.getZ() );
-
-        Tessellator tessellator = Tessellator.getInstance();
-        BufferBuilder buffer = tessellator.getBuffer();
-        buffer.begin( GL11.GL_LINES, DefaultVertexFormats.POSITION_COLOR );
+        MatrixStack transformStack = event.getMatrix();
+        Vector3d cameraPos = event.getInfo().getProjectedView();
+        transformStack.push();
+        transformStack.translate( pos.getX() - cameraPos.getX(), pos.getY() - cameraPos.getY(), pos.getZ() - cameraPos.getZ() );
 
         // I wish I could think of a better way to do this
-        if( faces.contains( NORTH ) || faces.contains( WEST ) ) line( buffer, 0, 0, 0, UP );
-        if( faces.contains( SOUTH ) || faces.contains( WEST ) ) line( buffer, 0, 0, 1, UP );
-        if( faces.contains( NORTH ) || faces.contains( EAST ) ) line( buffer, 1, 0, 0, UP );
-        if( faces.contains( SOUTH ) || faces.contains( EAST ) ) line( buffer, 1, 0, 1, UP );
-        if( faces.contains( NORTH ) || faces.contains( DOWN ) ) line( buffer, 0, 0, 0, EAST );
-        if( faces.contains( SOUTH ) || faces.contains( DOWN ) ) line( buffer, 0, 0, 1, EAST );
-        if( faces.contains( NORTH ) || faces.contains( UP ) ) line( buffer, 0, 1, 0, EAST );
-        if( faces.contains( SOUTH ) || faces.contains( UP ) ) line( buffer, 0, 1, 1, EAST );
-        if( faces.contains( WEST ) || faces.contains( DOWN ) ) line( buffer, 0, 0, 0, SOUTH );
-        if( faces.contains( EAST ) || faces.contains( DOWN ) ) line( buffer, 1, 0, 0, SOUTH );
-        if( faces.contains( WEST ) || faces.contains( UP ) ) line( buffer, 0, 1, 0, SOUTH );
-        if( faces.contains( EAST ) || faces.contains( UP ) ) line( buffer, 1, 1, 0, SOUTH );
+        IVertexBuilder buffer = event.getBuffers().getBuffer( RenderType.getLines() );
+        Matrix4f transform = transformStack.getLast().getMatrix();
+        if( faces.contains( NORTH ) || faces.contains( WEST ) ) line( buffer, transform, 0, 0, 0, UP );
+        if( faces.contains( SOUTH ) || faces.contains( WEST ) ) line( buffer, transform, 0, 0, 1, UP );
+        if( faces.contains( NORTH ) || faces.contains( EAST ) ) line( buffer, transform, 1, 0, 0, UP );
+        if( faces.contains( SOUTH ) || faces.contains( EAST ) ) line( buffer, transform, 1, 0, 1, UP );
+        if( faces.contains( NORTH ) || faces.contains( DOWN ) ) line( buffer, transform, 0, 0, 0, EAST );
+        if( faces.contains( SOUTH ) || faces.contains( DOWN ) ) line( buffer, transform, 0, 0, 1, EAST );
+        if( faces.contains( NORTH ) || faces.contains( UP ) ) line( buffer, transform, 0, 1, 0, EAST );
+        if( faces.contains( SOUTH ) || faces.contains( UP ) ) line( buffer, transform, 0, 1, 1, EAST );
+        if( faces.contains( WEST ) || faces.contains( DOWN ) ) line( buffer, transform, 0, 0, 0, SOUTH );
+        if( faces.contains( EAST ) || faces.contains( DOWN ) ) line( buffer, transform, 1, 0, 0, SOUTH );
+        if( faces.contains( WEST ) || faces.contains( UP ) ) line( buffer, transform, 0, 1, 0, SOUTH );
+        if( faces.contains( EAST ) || faces.contains( UP ) ) line( buffer, transform, 1, 1, 0, SOUTH );
 
-        tessellator.draw();
-
-        GlStateManager.popMatrix();
-        GlStateManager.depthMask( true );
-        GlStateManager.enableTexture();
-        GlStateManager.disableBlend();
+        transformStack.pop();
     }
 
-    private static void line( BufferBuilder buffer, int x, int y, int z, Direction direction )
+    private static void line( IVertexBuilder buffer, Matrix4f transform, float x, float y, float z, Direction direction )
     {
-        double minX = x == 0 ? -EXPAND : 1 + EXPAND;
-        double minY = y == 0 ? -EXPAND : 1 + EXPAND;
-        double minZ = z == 0 ? -EXPAND : 1 + EXPAND;
-
-        buffer.pos( minX, minY, minZ ).color( 0, 0, 0, 0.4f ).endVertex();
-        buffer.pos(
-            minX + direction.getXOffset() * (1 + EXPAND * 2),
-            minY + direction.getYOffset() * (1 + EXPAND * 2),
-            minZ + direction.getZOffset() * (1 + EXPAND * 2)
+        buffer.pos( transform, x, y, z ).color( 0, 0, 0, 0.4f ).endVertex();
+        buffer.pos( transform,
+            x + direction.getXOffset(),
+            y + direction.getYOffset(),
+            z + direction.getZOffset()
         ).color( 0, 0, 0, 0.4f ).endVertex();
     }
 }

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

@@ -0,0 +1,164 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2020. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+
+package dan200.computercraft.client.render;
+
+import com.google.common.base.Strings;
+import com.mojang.blaze3d.platform.GlStateManager;
+import com.mojang.blaze3d.systems.RenderSystem;
+import dan200.computercraft.ComputerCraft;
+import dan200.computercraft.client.gui.FixedWidthFontRenderer;
+import dan200.computercraft.shared.util.Palette;
+import net.minecraft.client.renderer.texture.TextureUtil;
+import net.minecraft.util.math.vector.Matrix4f;
+import org.lwjgl.BufferUtils;
+import org.lwjgl.opengl.GL13;
+import org.lwjgl.opengl.GL20;
+
+import java.io.InputStream;
+import java.nio.FloatBuffer;
+
+class MonitorTextureBufferShader
+{
+    static final int TEXTURE_INDEX = GL13.GL_TEXTURE3;
+
+    private static final FloatBuffer MATRIX_BUFFER = BufferUtils.createFloatBuffer( 16 );
+    private static final FloatBuffer PALETTE_BUFFER = BufferUtils.createFloatBuffer( 16 * 3 );
+
+    private static int uniformMv;
+
+    private static int uniformFont;
+    private static int uniformWidth;
+    private static int uniformHeight;
+    private static int uniformTbo;
+    private static int uniformPalette;
+
+    private static boolean initialised;
+    private static boolean ok;
+    private static int program;
+
+    static void setupUniform( Matrix4f transform, int width, int height, Palette palette, boolean greyscale )
+    {
+        MATRIX_BUFFER.rewind();
+        transform.write( MATRIX_BUFFER );
+        MATRIX_BUFFER.rewind();
+        RenderSystem.glUniformMatrix4( uniformMv, false, MATRIX_BUFFER );
+
+        RenderSystem.glUniform1i( uniformWidth, width );
+        RenderSystem.glUniform1i( uniformHeight, height );
+
+        // TODO: Cache this? Maybe??
+        PALETTE_BUFFER.rewind();
+        for( int i = 0; i < 16; i++ )
+        {
+            double[] colour = palette.getColour( i );
+            if( greyscale )
+            {
+                float f = FixedWidthFontRenderer.toGreyscale( colour );
+                PALETTE_BUFFER.put( f ).put( f ).put( f );
+            }
+            else
+            {
+                PALETTE_BUFFER.put( (float) colour[0] ).put( (float) colour[1] ).put( (float) colour[2] );
+            }
+        }
+        PALETTE_BUFFER.flip();
+        RenderSystem.glUniform3( uniformPalette, PALETTE_BUFFER );
+    }
+
+    static boolean use()
+    {
+        if( initialised )
+        {
+            if( ok ) GlStateManager.useProgram( program );
+            return ok;
+        }
+
+        if( ok = load() )
+        {
+            GL20.glUseProgram( program );
+            RenderSystem.glUniform1i( uniformFont, 0 );
+            RenderSystem.glUniform1i( uniformTbo, TEXTURE_INDEX - GL13.GL_TEXTURE0 );
+        }
+
+        return ok;
+    }
+
+    private static boolean load()
+    {
+        initialised = true;
+
+        try
+        {
+            int vertexShader = loadShader( GL20.GL_VERTEX_SHADER, "assets/computercraft/shaders/monitor.vert" );
+            int fragmentShader = loadShader( GL20.GL_FRAGMENT_SHADER, "assets/computercraft/shaders/monitor.frag" );
+
+            program = GlStateManager.createProgram();
+            GlStateManager.attachShader( program, vertexShader );
+            GlStateManager.attachShader( program, fragmentShader );
+            GL20.glBindAttribLocation( program, 0, "v_pos" );
+
+            GlStateManager.linkProgram( program );
+            boolean ok = GlStateManager.getProgram( program, GL20.GL_LINK_STATUS ) != 0;
+            String log = GlStateManager.getProgramInfoLog( program, Short.MAX_VALUE ).trim();
+            if( !Strings.isNullOrEmpty( log ) )
+            {
+                ComputerCraft.log.warn( "Problems when linking monitor shader: {}", log );
+            }
+
+            GL20.glDetachShader( program, vertexShader );
+            GL20.glDetachShader( program, fragmentShader );
+            GlStateManager.deleteShader( vertexShader );
+            GlStateManager.deleteShader( fragmentShader );
+
+            if( !ok ) return false;
+
+            uniformMv = getUniformLocation( program, "u_mv" );
+            uniformFont = getUniformLocation( program, "u_font" );
+            uniformWidth = getUniformLocation( program, "u_width" );
+            uniformHeight = getUniformLocation( program, "u_height" );
+            uniformTbo = getUniformLocation( program, "u_tbo" );
+            uniformPalette = getUniformLocation( program, "u_palette" );
+
+            ComputerCraft.log.info( "Loaded monitor shader." );
+            return true;
+        }
+        catch( Exception e )
+        {
+            ComputerCraft.log.error( "Cannot load monitor shaders", e );
+            return false;
+        }
+    }
+
+    private static int loadShader( int kind, String path )
+    {
+        InputStream stream = TileEntityMonitorRenderer.class.getClassLoader().getResourceAsStream( path );
+        if( stream == null ) throw new IllegalArgumentException( "Cannot find " + path );
+        String contents = TextureUtil.readResourceAsString( stream );
+
+        int shader = GlStateManager.createShader( kind );
+
+        GlStateManager.shaderSource( shader, contents );
+        GlStateManager.compileShader( shader );
+
+        boolean ok = GlStateManager.getShader( shader, GL20.GL_COMPILE_STATUS ) != 0;
+        String log = GlStateManager.getShaderInfoLog( shader, Short.MAX_VALUE ).trim();
+        if( !Strings.isNullOrEmpty( log ) )
+        {
+            ComputerCraft.log.warn( "Problems when loading monitor shader {}: {}", path, log );
+        }
+
+        if( !ok ) throw new IllegalStateException( "Cannot compile shader " + path );
+        return shader;
+    }
+
+    private static int getUniformLocation( int program, String name )
+    {
+        int uniform = GlStateManager.getUniformLocation( program, name );
+        if( uniform == -1 ) throw new IllegalStateException( "Cannot find uniform " + name );
+        return uniform;
+    }
+}

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

@@ -5,17 +5,16 @@
  */
 package dan200.computercraft.client.render;
 
-import com.mojang.blaze3d.platform.GlStateManager;
-import com.mojang.blaze3d.platform.GlStateManager.DestFactor;
-import com.mojang.blaze3d.platform.GlStateManager.SourceFactor;
+import com.mojang.blaze3d.vertex.IVertexBuilder;
 import dan200.computercraft.client.gui.FixedWidthFontRenderer;
 import dan200.computercraft.core.terminal.TextBuffer;
 import dan200.computercraft.shared.util.Palette;
-import net.minecraft.client.Minecraft;
-import net.minecraft.client.renderer.BufferBuilder;
-import net.minecraft.client.renderer.Tessellator;
+import net.minecraft.client.renderer.IRenderTypeBuffer;
+import net.minecraft.client.renderer.RenderState;
+import net.minecraft.client.renderer.RenderType;
 import net.minecraft.client.renderer.vertex.DefaultVertexFormats;
 import net.minecraft.util.ResourceLocation;
+import net.minecraft.util.math.vector.Matrix4f;
 import org.lwjgl.opengl.GL11;
 
 import static dan200.computercraft.client.gui.FixedWidthFontRenderer.FONT_HEIGHT;
@@ -24,7 +23,7 @@ import static dan200.computercraft.shared.media.items.ItemPrintout.LINES_PER_PAG
 public final class PrintoutRenderer
 {
     private static final ResourceLocation BG = new ResourceLocation( "computercraft", "textures/gui/printout.png" );
-    private static final double BG_SIZE = 256.0;
+    private static final float BG_SIZE = 256.0f;
 
     /**
      * Width of a page.
@@ -61,27 +60,24 @@ public final class PrintoutRenderer
 
     private PrintoutRenderer() {}
 
-    public static void drawText( int x, int y, int start, TextBuffer[] text, TextBuffer[] colours )
+    public static void drawText( Matrix4f transform, IRenderTypeBuffer renderer, int x, int y, int start, TextBuffer[] text, TextBuffer[] colours )
     {
+        IVertexBuilder buffer = renderer.getBuffer( FixedWidthFontRenderer.TYPE );
         for( int line = 0; line < LINES_PER_PAGE && line < text.length; line++ )
         {
-            FixedWidthFontRenderer.drawString(
+            FixedWidthFontRenderer.drawString( transform, buffer,
                 x, y + line * FONT_HEIGHT, text[start + line], colours[start + line], null, Palette.DEFAULT,
                 false, 0, 0
             );
         }
     }
 
-    public static void drawText( int x, int y, int start, String[] text, String[] colours )
+    public static void drawText( Matrix4f transform, IRenderTypeBuffer renderer, int x, int y, int start, String[] text, String[] colours )
     {
-        GlStateManager.color4f( 1.0f, 1.0f, 1.0f, 1.0f );
-        GlStateManager.enableBlend();
-        GlStateManager.enableTexture();
-        GlStateManager.blendFuncSeparate( SourceFactor.SRC_ALPHA, DestFactor.ONE_MINUS_SRC_ALPHA, SourceFactor.ONE, DestFactor.ZERO );
-
+        IVertexBuilder buffer = renderer.getBuffer( FixedWidthFontRenderer.TYPE );
         for( int line = 0; line < LINES_PER_PAGE && line < text.length; line++ )
         {
-            FixedWidthFontRenderer.drawString(
+            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
@@ -89,55 +85,46 @@ public final class PrintoutRenderer
         }
     }
 
-    public static void drawBorder( double x, double y, double z, int page, int pages, boolean isBook )
+    public static void drawBorder( Matrix4f transform, IRenderTypeBuffer renderer, float x, float y, float z, int page, int pages, boolean isBook )
     {
-        GlStateManager.color4f( 1.0f, 1.0f, 1.0f, 1.0f );
-        GlStateManager.enableBlend();
-        GlStateManager.enableTexture();
-        GlStateManager.blendFuncSeparate( SourceFactor.SRC_ALPHA, DestFactor.ONE_MINUS_SRC_ALPHA, SourceFactor.ONE, DestFactor.ZERO );
-
-        Minecraft.getInstance().getTextureManager().bindTexture( BG );
-
-        Tessellator tessellator = Tessellator.getInstance();
-        BufferBuilder buffer = tessellator.getBuffer();
-        buffer.begin( GL11.GL_QUADS, DefaultVertexFormats.POSITION_TEX );
-
         int leftPages = page;
         int rightPages = pages - page - 1;
 
+        IVertexBuilder buffer = renderer.getBuffer( Type.TYPE );
+
         if( isBook )
         {
             // Border
-            double offset = offsetAt( pages );
-            final double left = x - 4 - offset;
-            final double right = x + X_SIZE + offset - 4;
+            float offset = offsetAt( pages );
+            float left = x - 4 - offset;
+            float right = x + X_SIZE + offset - 4;
 
             // Left and right border
-            drawTexture( buffer, left - 4, y - 8, z - 0.02, COVER_X, 0, COVER_SIZE, Y_SIZE + COVER_SIZE * 2 );
-            drawTexture( buffer, right, y - 8, z - 0.02, COVER_X + COVER_SIZE, 0, COVER_SIZE, Y_SIZE + COVER_SIZE * 2 );
+            drawTexture( transform, buffer, left - 4, y - 8, z - 0.02f, COVER_X, 0, COVER_SIZE, Y_SIZE + COVER_SIZE * 2 );
+            drawTexture( transform, buffer, right, y - 8, z - 0.02f, COVER_X + COVER_SIZE, 0, COVER_SIZE, Y_SIZE + COVER_SIZE * 2 );
 
             // Draw centre panel (just stretched texture, sorry).
-            drawTexture( buffer,
-                x - offset, y, z - 0.02, X_SIZE + offset * 2, Y_SIZE,
+            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
             );
 
-            double borderX = left;
+            float borderX = left;
             while( borderX < right )
             {
                 double thisWidth = Math.min( right - borderX, X_SIZE );
-                drawTexture( buffer, borderX, y - 8, z - 0.02, 0, COVER_Y, thisWidth, COVER_SIZE );
-                drawTexture( buffer, borderX, y + Y_SIZE - 4, z - 0.02, 0, COVER_Y + COVER_SIZE, thisWidth, COVER_SIZE );
+                drawTexture( transform, buffer, borderX, y - 8, z - 0.02f, 0, COVER_Y, (float) thisWidth, COVER_SIZE );
+                drawTexture( transform, buffer, borderX, y + Y_SIZE - 4, z - 0.02f, 0, COVER_Y + COVER_SIZE, (float) thisWidth, COVER_SIZE );
                 borderX += thisWidth;
             }
         }
 
         // Left half
-        drawTexture( buffer, x, y, z, X_FOLD_SIZE * 2, 0, X_SIZE / 2.0f, Y_SIZE );
+        drawTexture( transform, buffer, x, y, z, X_FOLD_SIZE * 2, 0, X_SIZE / 2.0f, Y_SIZE );
         for( int n = 0; n <= leftPages; n++ )
         {
-            drawTexture( buffer,
-                x - offsetAt( n ), y, z - 1e-3 * 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
@@ -145,38 +132,54 @@ public final class PrintoutRenderer
         }
 
         // Right half
-        drawTexture( buffer, x + X_SIZE / 2.0f, y, z, X_FOLD_SIZE * 2 + X_SIZE / 2.0f, 0, X_SIZE / 2.0f, Y_SIZE );
+        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 );
         for( int n = 0; n <= rightPages; n++ )
         {
-            drawTexture( buffer,
-                x + (X_SIZE - X_FOLD_SIZE) + offsetAt( n ), y, z - 1e-3 * 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
             );
         }
-
-        tessellator.draw();
     }
 
-    private static void drawTexture( BufferBuilder buffer, double x, double y, double z, double u, double v, double width, double height )
+    private static void drawTexture( Matrix4f matrix, IVertexBuilder buffer, float x, float y, float z, float u, float v, float width, float height )
     {
-        buffer.pos( x, y + height, z ).tex( u / BG_SIZE, (v + height) / BG_SIZE ).endVertex();
-        buffer.pos( x + width, y + height, z ).tex( (u + width) / BG_SIZE, (v + height) / BG_SIZE ).endVertex();
-        buffer.pos( x + width, y, z ).tex( (u + width) / BG_SIZE, v / BG_SIZE ).endVertex();
-        buffer.pos( x, y, z ).tex( u / BG_SIZE, v / BG_SIZE ).endVertex();
+        buffer.pos( matrix, x, y + height, z ).tex( u / BG_SIZE, (v + height) / BG_SIZE ).endVertex();
+        buffer.pos( matrix, x + width, y + height, z ).tex( (u + width) / BG_SIZE, (v + height) / BG_SIZE ).endVertex();
+        buffer.pos( matrix, x + width, y, z ).tex( (u + width) / BG_SIZE, v / BG_SIZE ).endVertex();
+        buffer.pos( matrix, x, y, z ).tex( u / BG_SIZE, v / BG_SIZE ).endVertex();
     }
 
-    private static void drawTexture( BufferBuilder buffer, double x, double y, double z, double width, double height, double u, double v, double tWidth, double tHeight )
+    private static void drawTexture( Matrix4f matrix, IVertexBuilder buffer, float x, float y, float z, float width, float height, float u, float v, float tWidth, float tHeight )
     {
-        buffer.pos( x, y + height, z ).tex( u / BG_SIZE, (v + tHeight) / BG_SIZE ).endVertex();
-        buffer.pos( x + width, y + height, z ).tex( (u + tWidth) / BG_SIZE, (v + tHeight) / BG_SIZE ).endVertex();
-        buffer.pos( x + width, y, z ).tex( (u + tWidth) / BG_SIZE, v / BG_SIZE ).endVertex();
-        buffer.pos( x, y, z ).tex( u / BG_SIZE, v / BG_SIZE ).endVertex();
+        buffer.pos( matrix, x, y + height, z ).tex( u / BG_SIZE, (v + tHeight) / BG_SIZE ).endVertex();
+        buffer.pos( matrix, x + width, y + height, z ).tex( (u + tWidth) / BG_SIZE, (v + tHeight) / BG_SIZE ).endVertex();
+        buffer.pos( matrix, x + width, y, z ).tex( (u + tWidth) / BG_SIZE, v / BG_SIZE ).endVertex();
+        buffer.pos( matrix, x, y, z ).tex( u / BG_SIZE, v / BG_SIZE ).endVertex();
     }
 
-    public static double offsetAt( int page )
+    public static float offsetAt( int page )
     {
-        return 32 * (1 - Math.pow( 1.2, -page ));
+        return (float) (32 * (1 - Math.pow( 1.2, -page )));
+    }
+
+    private static final class Type extends RenderState
+    {
+        static final RenderType TYPE = RenderType.makeType(
+            "printout_background", DefaultVertexFormats.POSITION_TEX, GL11.GL_QUADS, 1024,
+            false, false, // useDelegate, needsSorting
+            RenderType.State.getBuilder()
+                .texture( new RenderState.TextureState( BG, false, false ) ) // blur, minimap
+                .alpha( DEFAULT_ALPHA )
+                .lightmap( LIGHTMAP_DISABLED )
+                .build( false )
+        );
+
+        private Type( String name, Runnable setup, Runnable destroy )
+        {
+            super( name, setup, destroy );
+        }
     }
 }

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

@@ -1,140 +0,0 @@
-/*
- * This file is part of ComputerCraft - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2020. Do not distribute without permission.
- * Send enquiries to dratcliffe@gmail.com
- */
-package dan200.computercraft.client.render;
-
-import com.mojang.blaze3d.platform.GlStateManager;
-import dan200.computercraft.ComputerCraft;
-import dan200.computercraft.shared.peripheral.modem.wired.BlockCable;
-import dan200.computercraft.shared.peripheral.modem.wired.CableModemVariant;
-import dan200.computercraft.shared.peripheral.modem.wired.CableShapes;
-import dan200.computercraft.shared.peripheral.modem.wired.TileCable;
-import dan200.computercraft.shared.util.WorldUtil;
-import net.minecraft.block.Block;
-import net.minecraft.block.BlockState;
-import net.minecraft.client.Minecraft;
-import net.minecraft.client.renderer.BufferBuilder;
-import net.minecraft.client.renderer.Tessellator;
-import net.minecraft.client.renderer.WorldRenderer;
-import net.minecraft.client.renderer.model.IBakedModel;
-import net.minecraft.client.renderer.texture.TextureAtlasSprite;
-import net.minecraft.client.renderer.tileentity.TileEntityRenderer;
-import net.minecraft.client.renderer.vertex.DefaultVertexFormats;
-import net.minecraft.util.BlockRenderLayer;
-import net.minecraft.util.ResourceLocation;
-import net.minecraft.util.math.BlockPos;
-import net.minecraft.util.math.BlockRayTraceResult;
-import net.minecraft.util.math.RayTraceResult;
-import net.minecraft.world.World;
-import net.minecraftforge.client.ForgeHooksClient;
-import net.minecraftforge.client.model.data.EmptyModelData;
-import org.lwjgl.opengl.GL11;
-
-import javax.annotation.Nonnull;
-import java.util.Random;
-
-/**
- * Render breaking animation only over part of a {@link TileCable}.
- */
-public class TileEntityCableRenderer extends TileEntityRenderer<TileCable>
-{
-    private static final ResourceLocation[] DESTROY_STAGES = new ResourceLocation[10];
-    private static final Random random = new Random();
-
-    static
-    {
-        for( int i = 0; i < DESTROY_STAGES.length; i++ )
-        {
-            DESTROY_STAGES[i] = new ResourceLocation( "block/destroy_stage_" + i );
-        }
-    }
-
-    @Override
-    public void render( @Nonnull TileCable te, double x, double y, double z, float partialTicks, int destroyStage )
-    {
-        if( destroyStage < 0 ) return;
-
-        BlockPos pos = te.getPos();
-
-        Minecraft mc = Minecraft.getInstance();
-
-        RayTraceResult hit = mc.objectMouseOver;
-        if( hit == null || hit.getType() != RayTraceResult.Type.BLOCK || !((BlockRayTraceResult) hit).getPos().equals( pos ) )
-        {
-            return;
-        }
-
-        World world = te.getWorld();
-        BlockState state = world.getBlockState( pos );
-        Block block = state.getBlock();
-        if( block != ComputerCraft.Blocks.cable ) return;
-
-        state = WorldUtil.isVecInside( CableShapes.getModemShape( state ), hit.getHitVec().subtract( pos.getX(), pos.getY(), pos.getZ() ) )
-            ? block.getDefaultState().with( BlockCable.MODEM, state.get( BlockCable.MODEM ) )
-            : state.with( BlockCable.MODEM, CableModemVariant.None );
-
-        IBakedModel model = mc.getBlockRendererDispatcher().getModelForState( state );
-
-        preRenderDamagedBlocks();
-
-        ForgeHooksClient.setRenderLayer( block.getRenderLayer() );
-
-        // See BlockRendererDispatcher#renderBlockDamage
-        TextureAtlasSprite breakingTexture = mc.getTextureMap().getSprite( DESTROY_STAGES[destroyStage] );
-
-        BufferBuilder buffer = Tessellator.getInstance().getBuffer();
-        buffer.begin( GL11.GL_QUADS, DefaultVertexFormats.BLOCK );
-        buffer.setTranslation( x - pos.getX(), y - pos.getY(), z - pos.getZ() );
-        buffer.noColor();
-
-        mc.getBlockRendererDispatcher().getBlockModelRenderer().renderModel(
-            world,
-            ForgeHooksClient.getDamageModel( model, breakingTexture, state, world, pos, 0 ),
-            state, pos, buffer, true, random, state.getPositionRandom( pos ), EmptyModelData.INSTANCE
-        );
-
-        ForgeHooksClient.setRenderLayer( BlockRenderLayer.SOLID );
-
-        buffer.setTranslation( 0, 0, 0 );
-        Tessellator.getInstance().draw();
-
-        postRenderDamagedBlocks();
-    }
-
-    /**
-     * Set up the state for rendering block-breaking progress.
-     *
-     * @see WorldRenderer#preRenderDamagedBlocks()
-     */
-    private void preRenderDamagedBlocks()
-    {
-        GlStateManager.disableLighting();
-
-        GlStateManager.enableBlend();
-        GlStateManager.blendFuncSeparate( GlStateManager.SourceFactor.DST_COLOR, GlStateManager.DestFactor.SRC_COLOR, GlStateManager.SourceFactor.ONE, GlStateManager.DestFactor.ZERO );
-        GlStateManager.enableBlend();
-        GlStateManager.color4f( 1.0F, 1.0F, 1.0F, 0.5F );
-        GlStateManager.polygonOffset( -3.0F, -3.0F );
-        GlStateManager.enablePolygonOffset();
-        GlStateManager.alphaFunc( 516, 0.1F );
-        GlStateManager.enableAlphaTest();
-        GlStateManager.pushMatrix();
-    }
-
-    /**
-     * Tear down the state for rendering block-breaking progress.
-     *
-     * @see WorldRenderer#postRenderDamagedBlocks()
-     */
-    private void postRenderDamagedBlocks()
-    {
-        GlStateManager.disableAlphaTest();
-        GlStateManager.polygonOffset( 0.0F, 0.0F );
-        GlStateManager.disablePolygonOffset();
-        GlStateManager.disablePolygonOffset();
-        GlStateManager.depthMask( true );
-        GlStateManager.popMatrix();
-    }
-}

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

@@ -5,34 +5,59 @@
  */
 package dan200.computercraft.client.render;
 
-import com.mojang.blaze3d.platform.GLX;
+import com.mojang.blaze3d.matrix.MatrixStack;
 import com.mojang.blaze3d.platform.GlStateManager;
+import com.mojang.blaze3d.vertex.IVertexBuilder;
 import dan200.computercraft.client.FrameInfo;
 import dan200.computercraft.client.gui.FixedWidthFontRenderer;
 import dan200.computercraft.core.terminal.Terminal;
+import dan200.computercraft.core.terminal.TextBuffer;
 import dan200.computercraft.shared.peripheral.monitor.ClientMonitor;
 import dan200.computercraft.shared.peripheral.monitor.MonitorRenderer;
 import dan200.computercraft.shared.peripheral.monitor.TileMonitor;
+import dan200.computercraft.shared.util.Colour;
 import dan200.computercraft.shared.util.DirectionUtil;
-import net.minecraft.client.Minecraft;
 import net.minecraft.client.renderer.BufferBuilder;
+import net.minecraft.client.renderer.GLAllocation;
+import net.minecraft.client.renderer.IRenderTypeBuffer;
 import net.minecraft.client.renderer.Tessellator;
 import net.minecraft.client.renderer.tileentity.TileEntityRenderer;
+import net.minecraft.client.renderer.tileentity.TileEntityRendererDispatcher;
+import net.minecraft.client.renderer.vertex.DefaultVertexFormats;
 import net.minecraft.client.renderer.vertex.VertexBuffer;
 import net.minecraft.util.Direction;
 import net.minecraft.util.math.BlockPos;
+import net.minecraft.util.math.vector.Matrix4f;
+import net.minecraft.util.math.vector.TransformationMatrix;
+import net.minecraft.util.math.vector.Vector3f;
 import org.lwjgl.opengl.GL11;
+import org.lwjgl.opengl.GL13;
+import org.lwjgl.opengl.GL20;
+import org.lwjgl.opengl.GL31;
 
 import javax.annotation.Nonnull;
+import java.nio.ByteBuffer;
 
-import static dan200.computercraft.shared.peripheral.monitor.TileMonitor.RENDER_MARGIN;
+import static dan200.computercraft.client.gui.FixedWidthFontRenderer.*;
 
 public class TileEntityMonitorRenderer extends TileEntityRenderer<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.
+     */
     private static final float MARGIN = (float) (TileMonitor.RENDER_MARGIN * 1.1);
+    private static ByteBuffer tboContents;
+
+    private static final Matrix4f IDENTITY = TransformationMatrix.identity().getMatrix();
+
+    public TileEntityMonitorRenderer( TileEntityRendererDispatcher rendererDispatcher )
+    {
+        super( rendererDispatcher );
+    }
 
     @Override
-    public void render( @Nonnull TileMonitor monitor, double posX, double posY, double posZ, float f, int i )
+    public void render( @Nonnull TileMonitor monitor, float partialTicks, @Nonnull MatrixStack transform, @Nonnull IRenderTypeBuffer renderer, int lightmapCoord, int overlayLight )
     {
         // Render from the origin monitor
         ClientMonitor originTerminal = monitor.getClientMonitor();
@@ -54,9 +79,6 @@ public class TileEntityMonitorRenderer extends TileEntityRenderer<TileMonitor>
         originTerminal.lastRenderPos = monitorPos;
 
         BlockPos originPos = origin.getPos();
-        posX += originPos.getX() - monitorPos.getX();
-        posY += originPos.getY() - monitorPos.getY();
-        posZ += originPos.getZ() - monitorPos.getZ();
 
         // Determine orientation
         Direction dir = origin.getDirection();
@@ -64,130 +86,158 @@ public class TileEntityMonitorRenderer extends TileEntityRenderer<TileMonitor>
         float yaw = dir.getHorizontalAngle();
         float pitch = DirectionUtil.toPitchAngle( front );
 
-        GlStateManager.pushMatrix();
-
         // Setup initial transform
-        GlStateManager.translated( posX + 0.5, posY + 0.5, posZ + 0.5 );
-        GlStateManager.rotatef( -yaw, 0.0f, 1.0f, 0.0f );
-        GlStateManager.rotatef( pitch, 1.0f, 0.0f, 0.0f );
-        GlStateManager.translated(
-            -0.5 + TileMonitor.RENDER_BORDER + RENDER_MARGIN,
-            origin.getHeight() - 0.5 - (TileMonitor.RENDER_BORDER + RENDER_MARGIN) + 0,
+        transform.push();
+        transform.translate(
+            originPos.getX() - monitorPos.getX() + 0.5,
+            originPos.getY() - monitorPos.getY() + 0.5,
+            originPos.getZ() - monitorPos.getZ() + 0.5
+        );
+
+        transform.rotate( Vector3f.YN.rotationDegrees( yaw ) );
+        transform.rotate( Vector3f.XP.rotationDegrees( pitch ) );
+        transform.translate(
+            -0.5 + TileMonitor.RENDER_BORDER + TileMonitor.RENDER_MARGIN,
+            origin.getHeight() - 0.5 - (TileMonitor.RENDER_BORDER + TileMonitor.RENDER_MARGIN) + 0,
             0.5
         );
-        double xSize = origin.getWidth() - 2.0 * (RENDER_MARGIN + TileMonitor.RENDER_BORDER);
-        double ySize = origin.getHeight() - 2.0 * (RENDER_MARGIN + TileMonitor.RENDER_BORDER);
-
-        // Get renderers
-        Minecraft mc = Minecraft.getInstance();
-
-        // Set up render state for monitors. We disable writing to the depth buffer (we draw a "blocker" later),
-        // and setup lighting so that we render with a glow.
-        GlStateManager.depthMask( false );
-        GLX.glMultiTexCoord2f( GLX.GL_TEXTURE1, 0xFFFF, 0xFFFF );
-        GlStateManager.disableLighting();
-        mc.gameRenderer.disableLightmap();
+        double xSize = origin.getWidth() - 2.0 * (TileMonitor.RENDER_MARGIN + TileMonitor.RENDER_BORDER);
+        double ySize = origin.getHeight() - 2.0 * (TileMonitor.RENDER_MARGIN + TileMonitor.RENDER_BORDER);
 
+        // Draw the contents
         Terminal terminal = originTerminal.getTerminal();
         if( terminal != null )
         {
             // Draw a terminal
-            double xScale = xSize / (terminal.getWidth() * FixedWidthFontRenderer.FONT_WIDTH);
-            double yScale = ySize / (terminal.getHeight() * FixedWidthFontRenderer.FONT_HEIGHT);
+            int width = terminal.getWidth(), height = terminal.getHeight();
+            int pixelWidth = width * FONT_WIDTH, pixelHeight = height * FONT_HEIGHT;
+            double xScale = xSize / pixelWidth;
+            double yScale = ySize / pixelHeight;
+            transform.push();
+            transform.scale( (float) xScale, (float) -yScale, 1.0f );
 
-            GlStateManager.pushMatrix();
-            GlStateManager.scaled( (float) xScale, (float) -yScale, 1.0f );
+            Matrix4f matrix = transform.getLast().getMatrix();
 
-            renderTerminal( originTerminal, (float) (MARGIN / xScale), (float) (MARGIN / yScale) );
+            // Sneaky hack here: we get a buffer now in order to flush existing ones and set up the appropriate
+            // render state. I've no clue how well this'll work in future versions of Minecraft, but it does the trick
+            // for now.
+            IVertexBuilder buffer = renderer.getBuffer( FixedWidthFontRenderer.TYPE );
+            FixedWidthFontRenderer.TYPE.setupRenderState();
 
-            GlStateManager.popMatrix();
+            renderTerminal( matrix, originTerminal, (float) (MARGIN / xScale), (float) (MARGIN / yScale) );
+
+            // 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, buffer, 0, 0, terminal, !originTerminal.isColour() );
+
+            transform.pop();
         }
         else
         {
             FixedWidthFontRenderer.drawEmptyTerminal(
+                transform.getLast().getMatrix(), renderer,
                 -MARGIN, MARGIN,
                 (float) (xSize + 2 * MARGIN), (float) -(ySize + MARGIN * 2)
             );
         }
 
-        // Tear down render state for monitors.
-        GlStateManager.depthMask( true );
-        mc.gameRenderer.enableLightmap();
-        GlStateManager.enableLighting();
-
-        // Draw the depth blocker
-        GlStateManager.colorMask( false, false, false, false );
         FixedWidthFontRenderer.drawBlocker(
+            transform.getLast().getMatrix(), renderer,
             (float) -TileMonitor.RENDER_MARGIN, (float) TileMonitor.RENDER_MARGIN,
             (float) (xSize + 2 * TileMonitor.RENDER_MARGIN), (float) -(ySize + TileMonitor.RENDER_MARGIN * 2)
         );
-        GlStateManager.colorMask( true, true, true, true );
 
-        GlStateManager.popMatrix();
+        transform.pop();
     }
 
-    private static void renderTerminal( ClientMonitor monitor, float xMargin, float yMargin )
+    private static void renderTerminal( Matrix4f matrix, ClientMonitor monitor, float xMargin, float yMargin )
     {
-        Tessellator tessellator = Tessellator.getInstance();
-        BufferBuilder buffer = tessellator.getBuffer();
+        Terminal terminal = monitor.getTerminal();
 
+        MonitorRenderer renderType = MonitorRenderer.current();
         boolean redraw = monitor.pollTerminalChanged();
+        if( monitor.createBuffer( renderType ) ) redraw = true;
 
-        // Setup the buffers if needed. We get the renderer here, to avoid the (unlikely) race condition between
-        // creating the buffers and rendering.
-        MonitorRenderer renderer = MonitorRenderer.current();
-        if( monitor.createBuffer( renderer ) ) redraw = true;
-
-        FixedWidthFontRenderer.bindFont();
-
-        switch( renderer )
+        switch( renderType )
         {
+            case TBO:
+            {
+                if( !MonitorTextureBufferShader.use() ) return;
+
+                int width = terminal.getWidth(), height = terminal.getHeight();
+                int pixelWidth = width * FONT_WIDTH, pixelHeight = height * FONT_HEIGHT;
+
+                if( redraw )
+                {
+                    int size = width * height * 3;
+                    if( tboContents == null || tboContents.capacity() < size )
+                    {
+                        tboContents = GLAllocation.createDirectByteBuffer( size );
+                    }
+
+                    ByteBuffer monitorBuffer = tboContents;
+                    monitorBuffer.clear();
+                    for( int y = 0; y < height; y++ )
+                    {
+                        TextBuffer text = terminal.getLine( y ), textColour = terminal.getTextColourLine( y ), background = terminal.getBackgroundColourLine( y );
+                        for( int x = 0; x < width; x++ )
+                        {
+                            monitorBuffer.put( (byte) (text.charAt( x ) & 0xFF) );
+                            monitorBuffer.put( (byte) getColour( textColour.charAt( x ), Colour.WHITE ) );
+                            monitorBuffer.put( (byte) getColour( background.charAt( x ), Colour.BLACK ) );
+                        }
+                    }
+                    monitorBuffer.flip();
+
+                    GlStateManager.bindBuffer( GL31.GL_TEXTURE_BUFFER, monitor.tboBuffer );
+                    GlStateManager.bufferData( GL31.GL_TEXTURE_BUFFER, monitorBuffer, GL20.GL_STATIC_DRAW );
+                    GlStateManager.bindBuffer( GL31.GL_TEXTURE_BUFFER, 0 );
+                }
+
+                // Nobody knows what they're doing!
+                GlStateManager.activeTexture( MonitorTextureBufferShader.TEXTURE_INDEX );
+                GL11.glBindTexture( GL31.GL_TEXTURE_BUFFER, monitor.tboTexture );
+                GlStateManager.activeTexture( GL13.GL_TEXTURE0 );
+
+                MonitorTextureBufferShader.setupUniform( matrix, width, height, terminal.getPalette(), !monitor.isColour() );
+
+                Tessellator tessellator = Tessellator.getInstance();
+                BufferBuilder buffer = tessellator.getBuffer();
+                buffer.begin( GL11.GL_TRIANGLE_STRIP, DefaultVertexFormats.POSITION );
+                buffer.pos( -xMargin, -yMargin, 0 ).endVertex();
+                buffer.pos( -xMargin, pixelHeight + yMargin, 0 ).endVertex();
+                buffer.pos( pixelWidth + xMargin, -yMargin, 0 ).endVertex();
+                buffer.pos( pixelWidth + xMargin, pixelHeight + yMargin, 0 ).endVertex();
+                tessellator.draw();
+
+                GlStateManager.useProgram( 0 );
+                break;
+            }
+
             case VBO:
             {
                 VertexBuffer vbo = monitor.buffer;
                 if( redraw )
                 {
-                    renderTerminalTo( monitor, buffer, xMargin, yMargin );
-                    buffer.finishDrawing();
-                    buffer.reset();
-                    vbo.bufferData( buffer.getByteBuffer() );
+                    Tessellator tessellator = Tessellator.getInstance();
+                    BufferBuilder builder = tessellator.getBuffer();
+                    builder.begin( FixedWidthFontRenderer.TYPE.getDrawMode(), FixedWidthFontRenderer.TYPE.getVertexFormat() );
+                    FixedWidthFontRenderer.drawTerminalWithoutCursor(
+                        IDENTITY, builder, 0, 0,
+                        terminal, !monitor.isColour(), yMargin, yMargin, xMargin, xMargin
+                    );
+
+                    builder.finishDrawing();
+                    vbo.upload( builder );
                 }
 
                 vbo.bindBuffer();
-                setupBufferFormat();
-                vbo.drawArrays( GL11.GL_TRIANGLES );
+                FixedWidthFontRenderer.TYPE.getVertexFormat().setupBufferState( 0L );
+                vbo.draw( matrix, FixedWidthFontRenderer.TYPE.getDrawMode() );
                 VertexBuffer.unbindBuffer();
-
+                FixedWidthFontRenderer.TYPE.getVertexFormat().clearBufferState();
                 break;
             }
         }
-
-        // We don't draw the cursor with a buffer, as it's dynamic and so we'll end up refreshing far more than is
-        // reasonable.
-        FixedWidthFontRenderer.begin( buffer );
-        FixedWidthFontRenderer.drawCursor( buffer, 0, 0, monitor.getTerminal(), !monitor.isColour() );
-        tessellator.draw();
-    }
-
-    private static void renderTerminalTo( ClientMonitor monitor, BufferBuilder buffer, float xMargin, float yMargin )
-    {
-        FixedWidthFontRenderer.begin( buffer );
-        FixedWidthFontRenderer.drawTerminalWithoutCursor(
-            buffer, 0, 0,
-            monitor.getTerminal(), !monitor.isColour(), yMargin, yMargin, xMargin, xMargin
-        );
-    }
-
-    public static void setupBufferFormat()
-    {
-        int stride = FixedWidthFontRenderer.POSITION_COLOR_TEX.getSize();
-        GlStateManager.vertexPointer( 3, GL11.GL_FLOAT, stride, 0 );
-        GlStateManager.enableClientState( GL11.GL_VERTEX_ARRAY );
-
-        GlStateManager.colorPointer( 4, GL11.GL_UNSIGNED_BYTE, stride, 12 );
-        GlStateManager.enableClientState( GL11.GL_COLOR_ARRAY );
-
-        GlStateManager.texCoordPointer( 2, GL11.GL_FLOAT, stride, 16 );
-        GlStateManager.enableClientState( GL11.GL_TEXTURE_COORD_ARRAY );
     }
 }

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

@@ -5,7 +5,9 @@
  */
 package dan200.computercraft.client.render;
 
-import com.mojang.blaze3d.platform.GlStateManager;
+import com.mojang.blaze3d.matrix.MatrixStack;
+import com.mojang.blaze3d.vertex.IVertexBuilder;
+import dan200.computercraft.api.client.TransformedModel;
 import dan200.computercraft.api.turtle.ITurtleUpgrade;
 import dan200.computercraft.api.turtle.TurtleSide;
 import dan200.computercraft.shared.computer.core.ComputerFamily;
@@ -13,31 +15,26 @@ import dan200.computercraft.shared.turtle.blocks.TileTurtle;
 import dan200.computercraft.shared.util.DirectionUtil;
 import dan200.computercraft.shared.util.Holiday;
 import dan200.computercraft.shared.util.HolidayUtil;
-import net.minecraft.block.BlockState;
 import net.minecraft.client.Minecraft;
-import net.minecraft.client.renderer.BufferBuilder;
-import net.minecraft.client.renderer.GameRenderer;
-import net.minecraft.client.renderer.Tessellator;
+import net.minecraft.client.gui.FontRenderer;
+import net.minecraft.client.renderer.Atlases;
+import net.minecraft.client.renderer.IRenderTypeBuffer;
 import net.minecraft.client.renderer.model.BakedQuad;
 import net.minecraft.client.renderer.model.IBakedModel;
 import net.minecraft.client.renderer.model.ModelManager;
 import net.minecraft.client.renderer.model.ModelResourceLocation;
-import net.minecraft.client.renderer.texture.AtlasTexture;
 import net.minecraft.client.renderer.tileentity.TileEntityRenderer;
-import net.minecraft.client.renderer.vertex.DefaultVertexFormats;
-import net.minecraft.client.renderer.vertex.VertexFormat;
+import net.minecraft.client.renderer.tileentity.TileEntityRendererDispatcher;
 import net.minecraft.util.Direction;
 import net.minecraft.util.ResourceLocation;
 import net.minecraft.util.math.BlockRayTraceResult;
 import net.minecraft.util.math.RayTraceResult;
-import net.minecraft.util.math.Vec3d;
-import net.minecraftforge.client.ForgeHooksClient;
+import net.minecraft.util.math.vector.Matrix4f;
+import net.minecraft.util.math.vector.Vector3d;
+import net.minecraft.util.math.vector.Vector3f;
 import net.minecraftforge.client.model.data.EmptyModelData;
-import net.minecraftforge.client.model.pipeline.LightUtil;
-import org.apache.commons.lang3.tuple.Pair;
-import org.lwjgl.opengl.GL11;
 
-import javax.vecmath.Matrix4f;
+import javax.annotation.Nonnull;
 import java.util.List;
 import java.util.Random;
 
@@ -48,189 +45,147 @@ public class TileEntityTurtleRenderer extends TileEntityRenderer<TileTurtle>
     private static final ModelResourceLocation COLOUR_TURTLE_MODEL = new ModelResourceLocation( "computercraft:turtle_colour", "inventory" );
     private static final ModelResourceLocation ELF_OVERLAY_MODEL = new ModelResourceLocation( "computercraft:turtle_elf_overlay", "inventory" );
 
-    @Override
-    public void render( TileTurtle tileEntity, double posX, double posY, double posZ, float partialTicks, int breaking )
+    private final Random random = new Random( 0 );
+
+    public TileEntityTurtleRenderer( TileEntityRendererDispatcher renderDispatcher )
     {
-        if( tileEntity != null ) renderTurtleAt( tileEntity, posX, posY, posZ, partialTicks );
+        super( renderDispatcher );
     }
 
     public static ModelResourceLocation getTurtleModel( ComputerFamily family, boolean coloured )
     {
         switch( family )
         {
-            case Normal:
+            case NORMAL:
             default:
                 return coloured ? COLOUR_TURTLE_MODEL : NORMAL_TURTLE_MODEL;
-            case Advanced:
+            case ADVANCED:
                 return coloured ? COLOUR_TURTLE_MODEL : ADVANCED_TURTLE_MODEL;
         }
     }
 
     public static ModelResourceLocation getTurtleOverlayModel( ResourceLocation overlay, boolean christmas )
     {
-        if( overlay != null )
-        {
-            return new ModelResourceLocation( overlay, "inventory" );
-        }
-        else if( christmas )
-        {
-            return ELF_OVERLAY_MODEL;
-        }
-        else
-        {
-            return null;
-        }
+        if( overlay != null ) return new ModelResourceLocation( overlay, "inventory" );
+        if( christmas ) return ELF_OVERLAY_MODEL;
+        return null;
     }
 
-    private void renderTurtleAt( TileTurtle turtle, double posX, double posY, double posZ, float partialTicks )
+    @Override
+    public void render( @Nonnull TileTurtle turtle, float partialTicks, @Nonnull MatrixStack transform, @Nonnull IRenderTypeBuffer renderer, int lightmapCoord, int overlayLight )
     {
         // Render the label
         String label = turtle.createProxy().getLabel();
-        RayTraceResult hit = rendererDispatcher.cameraHitResult;
+        RayTraceResult hit = renderDispatcher.cameraHitResult;
         if( label != null && hit.getType() == RayTraceResult.Type.BLOCK && turtle.getPos().equals( ((BlockRayTraceResult) hit).getPos() ) )
         {
-            setLightmapDisabled( true );
-            GameRenderer.drawNameplate(
-                getFontRenderer(), label,
-                (float) posX + 0.5F, (float) posY + 1.2F, (float) posZ + 0.5F, 0,
-                rendererDispatcher.renderInfo.getYaw(), rendererDispatcher.renderInfo.getPitch(), false
-            );
-            setLightmapDisabled( false );
+            Minecraft mc = Minecraft.getInstance();
+            FontRenderer font = renderDispatcher.fontRenderer;
+
+            transform.push();
+            transform.translate( 0.5, 1.2, 0.5 );
+            transform.rotate( mc.getRenderManager().getCameraOrientation() );
+            transform.scale( -0.025f, -0.025f, 0.025f );
+
+            Matrix4f matrix = transform.getLast().getMatrix();
+            int opacity = (int) (mc.gameSettings.getTextBackgroundOpacity( 0.25f ) * 255) << 24;
+            float width = -font.getStringWidth( label ) / 2.0f;
+            font.renderString( label, width, (float) 0, 0x20ffffff, false, matrix, renderer, true, opacity, lightmapCoord );
+            font.renderString( label, width, (float) 0, 0xffffffff, false, matrix, renderer, false, 0, lightmapCoord );
+
+            transform.pop();
         }
 
-        GlStateManager.pushMatrix();
-        try
+        transform.push();
+
+        // Setup the transform.
+        Vector3d offset = turtle.getRenderOffset( partialTicks );
+        float yaw = turtle.getRenderYaw( partialTicks );
+        transform.translate( offset.x, offset.y, offset.z );
+
+        transform.translate( 0.5f, 0.5f, 0.5f );
+        transform.rotate( Vector3f.YP.rotationDegrees( 180.0f - yaw ) );
+        if( label != null && (label.equals( "Dinnerbone" ) || label.equals( "Grumm" )) )
         {
-            BlockState state = turtle.getBlockState();
-            // Setup the transform
-            Vec3d offset = turtle.getRenderOffset( partialTicks );
-            float yaw = turtle.getRenderYaw( partialTicks );
-            GlStateManager.translated( posX + offset.x, posY + offset.y, posZ + offset.z );
-            // Render the turtle
-            GlStateManager.translatef( 0.5f, 0.5f, 0.5f );
-            GlStateManager.rotatef( 180.0f - yaw, 0.0f, 1.0f, 0.0f );
-            if( label != null && (label.equals( "Dinnerbone" ) || label.equals( "Grumm" )) )
-            {
-                // Flip the model and swap the cull face as winding order will have changed.
-                GlStateManager.scalef( 1.0f, -1.0f, 1.0f );
-                GlStateManager.cullFace( GlStateManager.CullFace.FRONT );
-            }
-            GlStateManager.translatef( -0.5f, -0.5f, -0.5f );
-            // Render the turtle
-            int colour = turtle.getColour();
-            ComputerFamily family = turtle.getFamily();
-            ResourceLocation overlay = turtle.getOverlay();
-
-            renderModel( state, getTurtleModel( family, colour != -1 ), colour == -1 ? null : new int[] { colour } );
-
-            // Render the overlay
-            ModelResourceLocation overlayModel = getTurtleOverlayModel(
-                overlay,
-                HolidayUtil.getCurrentHoliday() == Holiday.Christmas
-            );
-            if( overlayModel != null )
-            {
-                GlStateManager.disableCull();
-                GlStateManager.enableBlend();
-                GlStateManager.blendFunc( GL11.GL_SRC_ALPHA, GL11.GL_ONE_MINUS_SRC_ALPHA );
-                try
-                {
-                    renderModel( state, overlayModel, null );
-                }
-                finally
-                {
-                    GlStateManager.disableBlend();
-                    GlStateManager.enableCull();
-                }
-            }
-
-            // Render the upgrades
-            renderUpgrade( state, turtle, TurtleSide.Left, partialTicks );
-            renderUpgrade( state, turtle, TurtleSide.Right, partialTicks );
+            // Flip the model
+            transform.scale( 1.0f, -1.0f, 1.0f );
         }
-        finally
+        transform.translate( -0.5f, -0.5f, -0.5f );
+
+        // Render the turtle
+        int colour = turtle.getColour();
+        ComputerFamily family = turtle.getFamily();
+        ResourceLocation overlay = turtle.getOverlay();
+
+        IVertexBuilder buffer = renderer.getBuffer( Atlases.getTranslucentCullBlockType() );
+        renderModel( transform, buffer, lightmapCoord, overlayLight, getTurtleModel( family, colour != -1 ), colour == -1 ? null : new int[] { colour } );
+
+        // Render the overlay
+        ModelResourceLocation overlayModel = getTurtleOverlayModel( overlay, HolidayUtil.getCurrentHoliday() == Holiday.CHRISTMAS );
+        if( overlayModel != null )
         {
-            GlStateManager.popMatrix();
-            GlStateManager.cullFace( GlStateManager.CullFace.BACK );
+            renderModel( transform, buffer, lightmapCoord, overlayLight, overlayModel, null );
         }
+
+        // Render the upgrades
+        renderUpgrade( transform, buffer, lightmapCoord, overlayLight, turtle, TurtleSide.LEFT, partialTicks );
+        renderUpgrade( transform, buffer, lightmapCoord, overlayLight, turtle, TurtleSide.RIGHT, partialTicks );
+
+        transform.pop();
     }
 
-    private void renderUpgrade( BlockState state, TileTurtle turtle, TurtleSide side, float f )
+    private void renderUpgrade( @Nonnull MatrixStack transform, @Nonnull IVertexBuilder renderer, int lightmapCoord, int overlayLight, TileTurtle turtle, TurtleSide side, float f )
     {
         ITurtleUpgrade upgrade = turtle.getUpgrade( side );
-        if( upgrade != null )
-        {
-            GlStateManager.pushMatrix();
-            try
-            {
-                float toolAngle = turtle.getToolRenderAngle( side, f );
-                GlStateManager.translatef( 0.0f, 0.5f, 0.5f );
-                GlStateManager.rotatef( -toolAngle, 1.0f, 0.0f, 0.0f );
-                GlStateManager.translatef( 0.0f, -0.5f, -0.5f );
+        if( upgrade == null ) return;
+        transform.push();
 
-                Pair<IBakedModel, Matrix4f> pair = upgrade.getModel( turtle.getAccess(), side );
-                if( pair != null )
-                {
-                    if( pair.getRight() != null )
-                    {
-                        ForgeHooksClient.multiplyCurrentGlMatrix( pair.getRight() );
-                    }
-                    if( pair.getLeft() != null )
-                    {
-                        renderModel( state, pair.getLeft(), null );
-                    }
-                }
-            }
-            finally
-            {
-                GlStateManager.popMatrix();
-            }
-        }
+        float toolAngle = turtle.getToolRenderAngle( side, f );
+        transform.translate( 0.0f, 0.5f, 0.5f );
+        transform.rotate( Vector3f.XN.rotationDegrees( toolAngle ) );
+        transform.translate( 0.0f, -0.5f, -0.5f );
+
+        TransformedModel model = upgrade.getModel( turtle.getAccess(), side );
+        model.getMatrix().push( transform );
+        renderModel( transform, renderer, lightmapCoord, overlayLight, model.getModel(), null );
+        transform.pop();
+
+        transform.pop();
     }
 
-    private void renderModel( BlockState state, ModelResourceLocation modelLocation, int[] tints )
+    private void renderModel( @Nonnull MatrixStack transform, @Nonnull IVertexBuilder renderer, int lightmapCoord, int overlayLight, ModelResourceLocation modelLocation, int[] tints )
     {
-        Minecraft mc = Minecraft.getInstance();
-        ModelManager modelManager = mc.getItemRenderer().getItemModelMesher().getModelManager();
-        renderModel( state, modelManager.getModel( modelLocation ), tints );
+        ModelManager modelManager = Minecraft.getInstance().getItemRenderer().getItemModelMesher().getModelManager();
+        renderModel( transform, renderer, lightmapCoord, overlayLight, modelManager.getModel( modelLocation ), tints );
     }
 
-    private void renderModel( BlockState state, IBakedModel model, int[] tints )
+    private void renderModel( @Nonnull MatrixStack transform, @Nonnull IVertexBuilder renderer, int lightmapCoord, int overlayLight, IBakedModel model, int[] tints )
     {
-        Random random = new Random( 0 );
-        Tessellator tessellator = Tessellator.getInstance();
-        rendererDispatcher.textureManager.bindTexture( AtlasTexture.LOCATION_BLOCKS_TEXTURE );
-        renderQuads( tessellator, model.getQuads( state, null, random, EmptyModelData.INSTANCE ), tints );
+        random.setSeed( 0 );
+        renderQuads( transform, renderer, lightmapCoord, overlayLight, model.getQuads( null, null, random, EmptyModelData.INSTANCE ), tints );
         for( Direction facing : DirectionUtil.FACINGS )
         {
-            renderQuads( tessellator, model.getQuads( state, facing, random, EmptyModelData.INSTANCE ), tints );
+            renderQuads( transform, renderer, lightmapCoord, overlayLight, model.getQuads( null, facing, random, EmptyModelData.INSTANCE ), tints );
         }
     }
 
-    private static void renderQuads( Tessellator tessellator, List<BakedQuad> quads, int[] tints )
+    private static void renderQuads( @Nonnull MatrixStack transform, @Nonnull IVertexBuilder buffer, int lightmapCoord, int overlayLight, List<BakedQuad> quads, int[] tints )
     {
-        BufferBuilder buffer = tessellator.getBuffer();
-        VertexFormat format = DefaultVertexFormats.ITEM;
-        buffer.begin( GL11.GL_QUADS, format );
-        for( BakedQuad quad : quads )
+        MatrixStack.Entry matrix = transform.getLast();
+
+        for( BakedQuad bakedquad : quads )
         {
-            VertexFormat quadFormat = quad.getFormat();
-            if( quadFormat != format )
+            int tint = -1;
+            if( tints != null && bakedquad.hasTintIndex() )
             {
-                tessellator.draw();
-                format = quadFormat;
-                buffer.begin( GL11.GL_QUADS, format );
+                int idx = bakedquad.getTintIndex();
+                if( idx >= 0 && idx < tints.length ) tint = tints[bakedquad.getTintIndex()];
             }
 
-            int colour = 0xFFFFFFFF;
-            if( quad.hasTintIndex() && tints != null )
-            {
-                int index = quad.getTintIndex();
-                if( index >= 0 && index < tints.length ) colour = tints[index] | 0xFF000000;
-            }
-
-            LightUtil.renderQuadColor( buffer, quad, colour );
+            float f = (float) (tint >> 16 & 255) / 255.0F;
+            float f1 = (float) (tint >> 8 & 255) / 255.0F;
+            float f2 = (float) (tint & 255) / 255.0F;
+            buffer.addVertexData( matrix, bakedquad, f, f1, f2, lightmapCoord, overlayLight, true );
         }
-        tessellator.draw();
     }
 }

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

@@ -5,28 +5,27 @@
  */
 package dan200.computercraft.client.render;
 
+import com.google.gson.JsonDeserializationContext;
+import com.google.gson.JsonObject;
+import com.mojang.datafixers.util.Pair;
 import dan200.computercraft.ComputerCraft;
-import net.minecraft.client.renderer.model.IBakedModel;
-import net.minecraft.client.renderer.model.IUnbakedModel;
-import net.minecraft.client.renderer.model.ModelBakery;
-import net.minecraft.client.renderer.texture.ISprite;
+import net.minecraft.client.renderer.model.*;
 import net.minecraft.client.renderer.texture.TextureAtlasSprite;
-import net.minecraft.client.renderer.vertex.VertexFormat;
 import net.minecraft.resources.IResourceManager;
+import net.minecraft.util.JSONUtils;
 import net.minecraft.util.ResourceLocation;
-import net.minecraftforge.client.model.ICustomModelLoader;
+import net.minecraftforge.client.model.IModelConfiguration;
+import net.minecraftforge.client.model.IModelLoader;
+import net.minecraftforge.client.model.geometry.IModelGeometry;
 
 import javax.annotation.Nonnull;
-import java.util.Arrays;
 import java.util.Collection;
+import java.util.HashSet;
 import java.util.Set;
 import java.util.function.Function;
-import java.util.stream.Collectors;
 
-public final class TurtleModelLoader implements ICustomModelLoader
+public final class TurtleModelLoader implements IModelLoader<TurtleModelLoader.TurtleModel>
 {
-    private static final ResourceLocation NORMAL_TURTLE_MODEL = new ResourceLocation( ComputerCraft.MOD_ID, "block/turtle_normal" );
-    private static final ResourceLocation ADVANCED_TURTLE_MODEL = new ResourceLocation( ComputerCraft.MOD_ID, "block/turtle_advanced" );
     private static final ResourceLocation COLOUR_TURTLE_MODEL = new ResourceLocation( ComputerCraft.MOD_ID, "block/turtle_colour" );
 
     public static final TurtleModelLoader INSTANCE = new TurtleModelLoader();
@@ -40,32 +39,15 @@ public final class TurtleModelLoader implements ICustomModelLoader
     {
     }
 
-    @Override
-    public boolean accepts( @Nonnull ResourceLocation name )
-    {
-        return name.getNamespace().equals( ComputerCraft.MOD_ID )
-            && (name.getPath().equals( "item/turtle_normal" ) || name.getPath().equals( "item/turtle_advanced" ));
-    }
-
     @Nonnull
     @Override
-    public IUnbakedModel loadModel( @Nonnull ResourceLocation name )
+    public TurtleModel read( @Nonnull JsonDeserializationContext deserializationContext, @Nonnull JsonObject modelContents )
     {
-        if( name.getNamespace().equals( ComputerCraft.MOD_ID ) )
-        {
-            switch( name.getPath() )
-            {
-                case "item/turtle_normal":
-                    return new TurtleModel( NORMAL_TURTLE_MODEL );
-                case "item/turtle_advanced":
-                    return new TurtleModel( ADVANCED_TURTLE_MODEL );
-            }
-        }
-
-        throw new IllegalStateException( "Loader does not accept " + name );
+        ResourceLocation model = new ResourceLocation( JSONUtils.getString( modelContents, "model" ) );
+        return new TurtleModel( model );
     }
 
-    private static final class TurtleModel implements IUnbakedModel
+    public static final class TurtleModel implements IModelGeometry<TurtleModel>
     {
         private final ResourceLocation family;
 
@@ -74,29 +56,21 @@ public final class TurtleModelLoader implements ICustomModelLoader
             this.family = family;
         }
 
-        @Nonnull
         @Override
-        public Collection<ResourceLocation> getDependencies()
+        public Collection<RenderMaterial> getTextures( IModelConfiguration owner, Function<ResourceLocation, IUnbakedModel> modelGetter, Set<Pair<String, String>> missingTextureErrors )
         {
-            return Arrays.asList( family, COLOUR_TURTLE_MODEL );
+            Set<RenderMaterial> materials = new HashSet<>();
+            materials.addAll( modelGetter.apply( family ).getTextures( modelGetter, missingTextureErrors ) );
+            materials.addAll( modelGetter.apply( COLOUR_TURTLE_MODEL ).getTextures( modelGetter, missingTextureErrors ) );
+            return materials;
         }
 
-        @Nonnull
         @Override
-        public Collection<ResourceLocation> getTextures( @Nonnull Function<ResourceLocation, IUnbakedModel> modelGetter, @Nonnull Set<String> missingTextureErrors )
-        {
-            return getDependencies().stream()
-                .flatMap( x -> modelGetter.apply( x ).getTextures( modelGetter, missingTextureErrors ).stream() )
-                .collect( Collectors.toSet() );
-        }
-
-        @Nonnull
-        @Override
-        public IBakedModel bake( @Nonnull ModelBakery bakery, @Nonnull Function<ResourceLocation, TextureAtlasSprite> spriteGetter, @Nonnull ISprite sprite, @Nonnull VertexFormat format )
+        public IBakedModel bake( IModelConfiguration owner, ModelBakery bakery, Function<RenderMaterial, TextureAtlasSprite> spriteGetter, IModelTransform transform, ItemOverrideList overrides, ResourceLocation modelLocation )
         {
             return new TurtleSmartItemModel(
-                bakery.getBakedModel( family, sprite, spriteGetter, format ),
-                bakery.getBakedModel( COLOUR_TURTLE_MODEL, sprite, spriteGetter, format )
+                bakery.getBakedModel( family, transform, spriteGetter ),
+                bakery.getBakedModel( COLOUR_TURTLE_MODEL, transform, spriteGetter )
             );
         }
     }

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

@@ -5,40 +5,39 @@
  */
 package dan200.computercraft.client.render;
 
+import dan200.computercraft.api.client.TransformedModel;
 import net.minecraft.block.BlockState;
 import net.minecraft.client.renderer.model.BakedQuad;
 import net.minecraft.client.renderer.model.IBakedModel;
 import net.minecraft.client.renderer.model.ItemOverrideList;
 import net.minecraft.client.renderer.texture.TextureAtlasSprite;
 import net.minecraft.util.Direction;
+import net.minecraft.util.math.vector.TransformationMatrix;
 import net.minecraftforge.client.model.data.EmptyModelData;
 import net.minecraftforge.client.model.data.IModelData;
+import net.minecraftforge.client.model.pipeline.BakedQuadBuilder;
+import net.minecraftforge.client.model.pipeline.TRSRTransformer;
 
 import javax.annotation.Nonnull;
-import javax.vecmath.Matrix4f;
 import java.util.*;
 
 public class TurtleMultiModel implements IBakedModel
 {
     private final IBakedModel m_baseModel;
     private final IBakedModel m_overlayModel;
-    private final Matrix4f m_generalTransform;
-    private final IBakedModel m_leftUpgradeModel;
-    private final Matrix4f m_leftUpgradeTransform;
-    private final IBakedModel m_rightUpgradeModel;
-    private final Matrix4f m_rightUpgradeTransform;
+    private final TransformationMatrix m_generalTransform;
+    private final TransformedModel m_leftUpgradeModel;
+    private final TransformedModel m_rightUpgradeModel;
     private List<BakedQuad> m_generalQuads = null;
     private Map<Direction, List<BakedQuad>> m_faceQuads = new EnumMap<>( Direction.class );
 
-    public TurtleMultiModel( IBakedModel baseModel, IBakedModel overlayModel, Matrix4f generalTransform, IBakedModel leftUpgradeModel, Matrix4f leftUpgradeTransform, IBakedModel rightUpgradeModel, Matrix4f rightUpgradeTransform )
+    public TurtleMultiModel( IBakedModel baseModel, IBakedModel overlayModel, TransformationMatrix generalTransform, TransformedModel leftUpgradeModel, TransformedModel rightUpgradeModel )
     {
         // Get the models
         m_baseModel = baseModel;
         m_overlayModel = overlayModel;
         m_leftUpgradeModel = leftUpgradeModel;
-        m_leftUpgradeTransform = leftUpgradeTransform;
         m_rightUpgradeModel = rightUpgradeModel;
-        m_rightUpgradeTransform = rightUpgradeTransform;
         m_generalTransform = generalTransform;
     }
 
@@ -69,30 +68,22 @@ public class TurtleMultiModel implements IBakedModel
     private List<BakedQuad> buildQuads( BlockState state, Direction side, Random rand )
     {
         ArrayList<BakedQuad> quads = new ArrayList<>();
-        ModelTransformer.transformQuadsTo( quads, m_baseModel.getQuads( state, side, rand, EmptyModelData.INSTANCE ), m_generalTransform );
+
+
+        transformQuadsTo( quads, m_baseModel.getQuads( state, side, rand, EmptyModelData.INSTANCE ), m_generalTransform );
         if( m_overlayModel != null )
         {
-            ModelTransformer.transformQuadsTo( quads, m_overlayModel.getQuads( state, side, rand, EmptyModelData.INSTANCE ), m_generalTransform );
+            transformQuadsTo( quads, m_overlayModel.getQuads( state, side, rand, EmptyModelData.INSTANCE ), m_generalTransform );
         }
         if( m_leftUpgradeModel != null )
         {
-            Matrix4f upgradeTransform = m_generalTransform;
-            if( m_leftUpgradeTransform != null )
-            {
-                upgradeTransform = new Matrix4f( m_generalTransform );
-                upgradeTransform.mul( m_leftUpgradeTransform );
-            }
-            ModelTransformer.transformQuadsTo( quads, m_leftUpgradeModel.getQuads( state, side, rand, EmptyModelData.INSTANCE ), upgradeTransform );
+            TransformationMatrix upgradeTransform = m_generalTransform.compose( m_leftUpgradeModel.getMatrix() );
+            transformQuadsTo( quads, m_leftUpgradeModel.getModel().getQuads( state, side, rand, EmptyModelData.INSTANCE ), upgradeTransform );
         }
         if( m_rightUpgradeModel != null )
         {
-            Matrix4f upgradeTransform = m_generalTransform;
-            if( m_rightUpgradeTransform != null )
-            {
-                upgradeTransform = new Matrix4f( m_generalTransform );
-                upgradeTransform.mul( m_rightUpgradeTransform );
-            }
-            ModelTransformer.transformQuadsTo( quads, m_rightUpgradeModel.getQuads( state, side, rand, EmptyModelData.INSTANCE ), upgradeTransform );
+            TransformationMatrix upgradeTransform = m_generalTransform.compose( m_rightUpgradeModel.getMatrix() );
+            transformQuadsTo( quads, m_rightUpgradeModel.getModel().getQuads( state, side, rand, EmptyModelData.INSTANCE ), upgradeTransform );
         }
         quads.trimToSize();
         return quads;
@@ -116,6 +107,12 @@ public class TurtleMultiModel implements IBakedModel
         return m_baseModel.isBuiltInRenderer();
     }
 
+    @Override
+    public boolean func_230044_c_()
+    {
+        return m_baseModel.func_230044_c_();
+    }
+
     @Nonnull
     @Override
     @Deprecated
@@ -138,4 +135,15 @@ public class TurtleMultiModel implements IBakedModel
     {
         return ItemOverrideList.EMPTY;
     }
+
+    private void transformQuadsTo( List<BakedQuad> output, List<BakedQuad> quads, TransformationMatrix transform )
+    {
+        for( BakedQuad quad : quads )
+        {
+            BakedQuadBuilder builder = new BakedQuadBuilder();
+            TRSRTransformer transformer = new TRSRTransformer( builder, transform );
+            quad.pipe( transformer );
+            output.add( builder.build() );
+        }
+    }
 }

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

@@ -6,14 +6,14 @@
 
 package dan200.computercraft.client.render;
 
-import dan200.computercraft.ComputerCraft;
+import com.mojang.blaze3d.matrix.MatrixStack;
 import dan200.computercraft.shared.turtle.core.TurtlePlayer;
+import net.minecraft.client.renderer.IRenderTypeBuffer;
 import net.minecraft.client.renderer.entity.EntityRenderer;
 import net.minecraft.client.renderer.entity.EntityRendererManager;
 import net.minecraft.util.ResourceLocation;
 
 import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
 
 public class TurtlePlayerRenderer extends EntityRenderer<TurtlePlayer>
 {
@@ -22,16 +22,15 @@ public class TurtlePlayerRenderer extends EntityRenderer<TurtlePlayer>
         super( renderManager );
     }
 
+    @Nonnull
     @Override
-    public void doRender( @Nonnull TurtlePlayer entity, double x, double y, double z, float entityYaw, float partialTicks )
+    public ResourceLocation getEntityTexture( @Nonnull TurtlePlayer entity )
     {
-        ComputerCraft.log.error( "Rendering TurtlePlayer on the client side, at {}", entity.getPosition() );
+        return ComputerBorderRenderer.BACKGROUND_NORMAL;
     }
 
-    @Nullable
     @Override
-    protected ResourceLocation getEntityTexture( @Nonnull TurtlePlayer entity )
+    public void render( @Nonnull TurtlePlayer entityIn, float entityYaw, float partialTicks, @Nonnull MatrixStack transform, @Nonnull IRenderTypeBuffer buffer, int packedLightIn )
     {
-        return null;
     }
 }