Merge pull request #497 from SquidDev-CC/ComputerCraft/feature/pocket-map

Add map-like rendering for pocket computers

.editorconfig

@@ -5,7 +5,9 @@ indent_style = space
 indent_size = 4
 end_of_line = lf
 charset = utf-8
-trim_trailing_whitespace = true
+# Sadly too many files have whitespace errors, so we leave this as is for
+# now and just make sure we don't introduce any more.
+# trim_trailing_whitespace = true
 insert_final_newline = true
 
 [*.md]

README.md

@@ -1,8 +1,8 @@
-# CC: Tweaked
+# ![CC: Tweaked](logo.png)
 [![Build Status](https://travis-ci.org/SquidDev-CC/CC-Tweaked.svg?branch=master)](https://travis-ci.org/SquidDev-CC/CC-Tweaked)
 
-CC: Tweaked is a fork of ComputerCraft which aims to provide more earlier access to the more experimental and 
-in-development features of the mod. For a more stable experience, I recommend checking out the 
+CC: Tweaked is a fork of ComputerCraft which aims to provide earlier access to the more experimental and in-development
+features of the mod. For a more stable experience, I recommend checking out the
 [original mod](https://github.com/dan200/ComputerCraft).
 
 ## What?

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

@@ -9,6 +9,7 @@ package dan200.computercraft;
 import com.google.common.base.CaseFormat;
 import dan200.computercraft.api.filesystem.IMount;
 import dan200.computercraft.api.filesystem.IWritableMount;
+import dan200.computercraft.api.lua.ILuaAPIFactory;
 import dan200.computercraft.api.media.IMedia;
 import dan200.computercraft.api.media.IMediaProvider;
 import dan200.computercraft.api.network.IPacketNetwork;
@@ -82,10 +83,7 @@ import java.io.*;
 import java.net.MalformedURLException;
 import java.net.URISyntaxException;
 import java.net.URL;
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
+import java.util.*;
 import java.util.zip.ZipEntry;
 import java.util.zip.ZipFile;
 
@@ -251,6 +249,7 @@ public class ComputerCraft
     private static List<IMediaProvider> mediaProviders = new ArrayList<>();
     private static List<ITurtlePermissionProvider> permissionProviders = new ArrayList<>();
     private static final Map<String, IPocketUpgrade> pocketUpgrades = new HashMap<>();
+    private static final Set<ILuaAPIFactory> apiFactories = new LinkedHashSet<>();
 
     // Implementation
     @Mod.Instance( value = ComputerCraft.MOD_ID )
@@ -673,6 +672,14 @@ public class ComputerCraft
         }
     }
 
+    public static void registerAPIFactory( ILuaAPIFactory provider )
+    {
+        if( provider != null )
+        {
+            apiFactories.add( provider );
+        }
+    }
+
     public static IPeripheral getPeripheralAt( World world, BlockPos pos, EnumFacing side )
     {
         // Try the handlers in order:
@@ -800,6 +807,11 @@ public class ComputerCraft
         return WirelessNetwork.getUniversal();
     }
 
+    public static Iterable<ILuaAPIFactory> getAPIFactories()
+    {
+        return apiFactories;
+    }
+
     public static int createUniqueNumberedSaveDir( World world, String parentSubPath )
     {
         return IDAssigner.getNextIDFromDirectory(new File(getWorldDir(world), parentSubPath));

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

@@ -8,6 +8,7 @@ package dan200.computercraft.api;
 
 import dan200.computercraft.api.filesystem.IMount;
 import dan200.computercraft.api.filesystem.IWritableMount;
+import dan200.computercraft.api.lua.ILuaAPIFactory;
 import dan200.computercraft.api.media.IMedia;
 import dan200.computercraft.api.media.IMediaProvider;
 import dan200.computercraft.api.network.IPacketNetwork;
@@ -311,6 +312,22 @@ public final class ComputerCraftAPI
         return null;
     }
 
+    public static void registerAPIFactory( @Nonnull ILuaAPIFactory upgrade )
+    {
+        findCC();
+        if( computerCraft_registerAPIFactory != null )
+        {
+            try
+            {
+                computerCraft_registerAPIFactory.invoke( null, upgrade );
+            }
+            catch( Exception e )
+            {
+                // It failed
+            }
+        }
+    }
+
     // The functions below here are private, and are used to interface with the non-API ComputerCraft classes.
     // Reflection is used here so you can develop your mod without decompiling ComputerCraft and including
     // it in your solution, and so your mod won't crash if ComputerCraft is installed.
@@ -354,6 +371,9 @@ public final class ComputerCraftAPI
                 } );
                 computerCraft_getWirelessNetwork = findCCMethod( "getWirelessNetwork", new Class<?>[] {
                 } );
+                computerCraft_registerAPIFactory = findCCMethod( "registerAPIFactory", new Class<?>[] {
+                    ILuaAPIFactory.class
+                } );
             } catch( Exception e ) {
                 System.out.println( "ComputerCraftAPI: ComputerCraft not found." );
             } finally {
@@ -390,4 +410,5 @@ public final class ComputerCraftAPI
     private static Method computerCraft_registerPermissionProvider = null;
     private static Method computerCraft_registerPocketUpgrade = null;
     private static Method computerCraft_getWirelessNetwork = null;
+    private static Method computerCraft_registerAPIFactory = null;
 }

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

@@ -0,0 +1,38 @@
+package dan200.computercraft.api.filesystem;
+
+import java.io.IOException;
+
+/**
+ * Provides a mount of the entire computer's file system.
+ *
+ * This exists for use by various APIs - one should not attempt to mount it.
+ */
+public interface IFileSystem extends IWritableMount
+{
+    /**
+     * Combine two paths together, reducing them into a normalised form.
+     *
+     * @param path  The main path.
+     * @param child The path to append.
+     * @return The combined, normalised path.
+     */
+    String combine( String path, String child );
+
+    /**
+     * Copy files from one location to another.
+     *
+     * @param from The location to copy from.
+     * @param to   The location to copy to. This should not exist.
+     * @throws IOException If the copy failed.
+     */
+    void copy( String from, String to ) throws IOException;
+
+    /**
+     * Move files from one location to another.
+     *
+     * @param from The location to move from.
+     * @param to   The location to move to. This should not exist.
+     * @throws IOException If the move failed.
+     */
+    void move( String from, String to ) throws IOException;
+}

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

@@ -0,0 +1,29 @@
+package dan200.computercraft.api.lua;
+
+import dan200.computercraft.api.filesystem.IFileSystem;
+import dan200.computercraft.api.peripheral.IComputerAccess;
+
+import javax.annotation.Nullable;
+
+/**
+ * An interface passed to {@link ILuaAPIFactory} in order to provide additional information
+ * about a computer.
+ */
+public interface IComputerSystem extends IComputerAccess
+{
+    /**
+     * Get the file system for this computer.
+     *
+     * @return The computer's file system, or {@code null} if it is not initialised.
+     */
+    @Nullable
+    IFileSystem getFileSystem();
+
+    /**
+     * Get the label for this computer
+     *
+     * @return This computer's label, or {@code null} if it is not set.
+     */
+    @Nullable
+    String getLabel();
+}

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

@@ -0,0 +1,47 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+
+package dan200.computercraft.api.lua;
+
+import dan200.computercraft.api.ComputerCraftAPI;
+
+/**
+ * Represents a {@link ILuaObject} which is stored as a global variable on computer startup.
+ *
+ * Before implementing this interface, consider alternative methods of providing methods. It is generally preferred
+ * to use peripherals to provide functionality to users.
+ *
+ * @see ILuaAPIFactory
+ * @see ComputerCraftAPI#registerAPIFactory(ILuaAPIFactory)
+ */
+public interface ILuaAPI extends ILuaObject
+{
+    /**
+     * Get the globals this API will be assigned to. This will override any other global, so you should
+     *
+     * @return A list of globals this API will be assigned to.
+     */
+    String[] getNames();
+
+    /**
+     * Called when the computer is turned on.
+     *
+     * One should only interact with the file system.
+     */
+    default void startup() { }
+
+    /**
+     * Called every time the computer is ticked. This can be used to process various.
+     */
+    default void update() { }
+
+    /**
+     * Called when the computer is turned off or unloaded.
+     *
+     * This should reset the state of the object, disposing any remaining file handles, or other resources.
+     */
+    default void shutdown() { }
+}

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

@@ -0,0 +1,24 @@
+package dan200.computercraft.api.lua;
+
+import dan200.computercraft.api.ComputerCraftAPI;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
+/**
+ * Construct an {@link ILuaAPI} for a specific computer.
+ *
+ * @see ILuaAPI
+ * @see ComputerCraftAPI#registerAPIFactory(ILuaAPIFactory)
+ */
+public interface ILuaAPIFactory
+{
+    /**
+     * Create a new API instance for a given computer.
+     *
+     * @param computer The computer this API is for.
+     * @return The created API, or {@code null} if one should not be injected.
+     */
+    @Nullable
+    ILuaAPI create( @Nonnull IComputerSystem computer );
+}

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

@@ -8,6 +8,7 @@ package dan200.computercraft.client.proxy;
 
 import dan200.computercraft.ComputerCraft;
 import dan200.computercraft.client.gui.*;
+import dan200.computercraft.client.render.ItemPocketRenderer;
 import dan200.computercraft.client.render.RenderOverlayCable;
 import dan200.computercraft.client.render.TileEntityCableRenderer;
 import dan200.computercraft.client.render.TileEntityMonitorRenderer;
@@ -454,6 +455,7 @@ public class ComputerCraftProxyClient extends ComputerCraftProxyCommon
         ForgeHandlers handlers = new ForgeHandlers();
         MinecraftForge.EVENT_BUS.register( handlers );
         MinecraftForge.EVENT_BUS.register( new RenderOverlayCable() );
+        MinecraftForge.EVENT_BUS.register( new ItemPocketRenderer() );
     }
 
     public class ForgeHandlers

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

@@ -0,0 +1,264 @@
+package dan200.computercraft.client.render;
+
+
+import dan200.computercraft.ComputerCraft;
+import dan200.computercraft.client.gui.FixedWidthFontRenderer;
+import dan200.computercraft.core.terminal.Terminal;
+import dan200.computercraft.core.terminal.TextBuffer;
+import dan200.computercraft.shared.computer.core.ClientComputer;
+import dan200.computercraft.shared.pocket.items.ItemPocketComputer;
+import dan200.computercraft.shared.util.Palette;
+import net.minecraft.client.Minecraft;
+import net.minecraft.client.renderer.GlStateManager;
+import net.minecraft.client.renderer.ItemRenderer;
+import net.minecraft.client.renderer.RenderItem;
+import net.minecraft.client.renderer.block.model.IBakedModel;
+import net.minecraft.client.renderer.block.model.ItemCameraTransforms;
+import net.minecraft.client.renderer.texture.TextureManager;
+import net.minecraft.client.renderer.texture.TextureMap;
+import net.minecraft.entity.player.EntityPlayer;
+import net.minecraft.item.ItemStack;
+import net.minecraft.util.EnumHand;
+import net.minecraft.util.EnumHandSide;
+import net.minecraft.util.math.MathHelper;
+import net.minecraftforge.client.ForgeHooksClient;
+import net.minecraftforge.client.event.RenderSpecificHandEvent;
+import net.minecraftforge.fml.common.eventhandler.SubscribeEvent;
+import net.minecraftforge.fml.relauncher.Side;
+import net.minecraftforge.fml.relauncher.SideOnly;
+import org.lwjgl.opengl.GL11;
+
+import static dan200.computercraft.client.gui.FixedWidthFontRenderer.FONT_HEIGHT;
+import static dan200.computercraft.client.gui.FixedWidthFontRenderer.FONT_WIDTH;
+
+/**
+ * Emulates map rendering for pocket computers
+ */
+@SideOnly(Side.CLIENT)
+public class ItemPocketRenderer
+{
+    @SubscribeEvent
+    public void renderItem( RenderSpecificHandEvent event )
+    {
+        ItemStack stack = event.getItemStack();
+        if( !(stack.getItem() instanceof ItemPocketComputer) ) return;
+
+        event.setCanceled( true );
+
+        EntityPlayer player = Minecraft.getMinecraft().player;
+
+        GlStateManager.pushMatrix();
+        if( event.getHand() == EnumHand.MAIN_HAND && player.getHeldItemOffhand().isEmpty() )
+        {
+            renderItemFirstCentre(
+                event.getInterpolatedPitch(),
+                event.getEquipProgress(),
+                event.getSwingProgress(),
+                stack
+            );
+        }
+        else
+        {
+            renderItemFirstPersonSide(
+                event.getHand() == EnumHand.MAIN_HAND ? player.getPrimaryHand() : player.getPrimaryHand().opposite(),
+                event.getEquipProgress(),
+                event.getSwingProgress(),
+                stack
+            );
+        }
+        GlStateManager.popMatrix();
+    }
+
+    /**
+     * The main rendering method for pocket computers and their associated terminal
+     *
+     * @param stack The stack to render
+     * @see ItemRenderer#renderMapFirstPerson(ItemStack)
+     */
+    private void renderPocketComputerItem( ItemStack stack )
+    {
+        // Setup various transformations. Note that these are partially adapated from the corresponding method
+        // in ItemRenderer
+        GlStateManager.disableLighting();
+
+        GlStateManager.rotate( 180f, 0f, 1f, 0f );
+        GlStateManager.rotate( 180f, 0f, 0f, 1f );
+        GlStateManager.scale( 0.5, 0.5, 0.5 );
+
+        ItemPocketComputer pocketComputer = ComputerCraft.Items.pocketComputer;
+        ClientComputer computer = pocketComputer.createClientComputer( stack );
+
+        {
+            // First render the background item. We use the item's model rather than a direct texture as this ensures 
+            // we display the pocket light and other such decorations. 
+            GlStateManager.pushMatrix();
+
+            GlStateManager.scale( 1.0f, -1.0f, 1.0f );
+
+            Minecraft minecraft = Minecraft.getMinecraft();
+            TextureManager textureManager = minecraft.getTextureManager();
+            RenderItem renderItem = minecraft.getRenderItem();
+
+            // Copy of RenderItem#renderItemModelIntoGUI but without the translation or scaling
+            textureManager.bindTexture( TextureMap.LOCATION_BLOCKS_TEXTURE );
+            textureManager.getTexture( TextureMap.LOCATION_BLOCKS_TEXTURE ).setBlurMipmap( false, false );
+
+            GlStateManager.enableRescaleNormal();
+            GlStateManager.enableAlpha();
+            GlStateManager.alphaFunc( GL11.GL_GREATER, 0.1F );
+            GlStateManager.enableBlend();
+            GlStateManager.blendFunc( GlStateManager.SourceFactor.SRC_ALPHA, GlStateManager.DestFactor.ONE_MINUS_SRC_ALPHA );
+            GlStateManager.color( 1.0F, 1.0F, 1.0F, 1.0F );
+
+            IBakedModel bakedmodel = renderItem.getItemModelWithOverrides( stack, null, null );
+            bakedmodel = ForgeHooksClient.handleCameraTransforms( bakedmodel, ItemCameraTransforms.TransformType.GUI, false );
+            renderItem.renderItem( stack, bakedmodel );
+
+            GlStateManager.disableAlpha();
+            GlStateManager.disableRescaleNormal();
+
+            GlStateManager.popMatrix();
+        }
+
+        // If we've a computer and terminal then attempt to render it.
+        if( computer != null )
+        {
+            Terminal terminal = computer.getTerminal();
+            if( terminal != null )
+            {
+                synchronized( terminal )
+                {
+                    GlStateManager.pushMatrix();
+                    GlStateManager.disableDepth();
+
+                    // Reset the position to be at the top left corner of the pocket computer
+                    // Note we translate towards the screen slightly too.
+                    GlStateManager.translate( -8 / 16.0, -8 / 16.0, 0.5 / 16.0 );
+                    // Translate to the top left of the screen.
+                    GlStateManager.translate( 4 / 16.0, 3 / 16.0, 0 );
+
+                    // Work out the scaling required to resize the terminal in order to fit on the computer
+                    final int margin = 2;
+                    int tw = terminal.getWidth();
+                    int th = terminal.getHeight();
+                    int width = tw * FONT_WIDTH + margin * 2;
+                    int height = th * FONT_HEIGHT + margin * 2;
+                    int max = Math.max( height, width );
+
+                    // The grid is 8 * 8 wide, so we start with a base of 1/2 (8 / 16).
+                    double scale = 1.0 / 2.0 / max;
+                    GlStateManager.scale( scale, scale, scale );
+
+                    // The margin/start positions are determined in order for the terminal to be centred.
+                    int startX = (max - width) / 2 + margin;
+                    int startY = (max - height) / 2 + margin;
+
+                    FixedWidthFontRenderer fontRenderer = (FixedWidthFontRenderer) ComputerCraft.getFixedWidthFontRenderer();
+                    boolean greyscale = !computer.isColour();
+                    Palette palette = terminal.getPalette();
+
+                    // Render the actual text
+                    for( int line = 0; line < th; ++line )
+                    {
+                        TextBuffer text = terminal.getLine( line );
+                        TextBuffer colour = terminal.getTextColourLine( line );
+                        TextBuffer backgroundColour = terminal.getBackgroundColourLine( line );
+                        fontRenderer.drawString(
+                            text, startX, startY + line * FONT_HEIGHT,
+                            colour, backgroundColour, margin, margin, greyscale, palette
+                        );
+                    }
+
+                    // And render the cursor;
+                    int tx = terminal.getCursorX(), ty = terminal.getCursorY();
+                    if( terminal.getCursorBlink() && ComputerCraft.getGlobalCursorBlink() &&
+                        tx >= 0 && ty >= 0 && tx < tw && ty < th )
+                    {
+                        TextBuffer cursorColour = new TextBuffer( "0123456789abcdef".charAt( terminal.getTextColour() ), 1 );
+                        fontRenderer.drawString(
+                            new TextBuffer( '_', 1 ), startX + FONT_WIDTH * tx, startY + FONT_HEIGHT * ty,
+                            cursorColour, null, 0, 0, greyscale, palette
+                        );
+                    }
+
+                    GlStateManager.enableDepth();
+                    GlStateManager.popMatrix();
+                }
+            }
+        }
+
+        GlStateManager.enableLighting();
+    }
+
+    /**
+     * Renders a pocket computer to one side of the player.
+     *
+     * @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 ItemRenderer#renderMapFirstPersonSide(float, EnumHandSide, float, ItemStack)
+     */
+    private void renderItemFirstPersonSide( EnumHandSide side, float equipProgress, float swingProgress, ItemStack stack )
+    {
+        Minecraft minecraft = Minecraft.getMinecraft();
+        float offset = side == EnumHandSide.RIGHT ? 1f : -1f;
+        GlStateManager.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.rotate( offset * 10f, 0f, 0f, 1f );
+            minecraft.getItemRenderer().renderArmFirstPerson( equipProgress, swingProgress, side );
+            GlStateManager.popMatrix();
+        }
+
+        // Setup the appropriate transformations. This is just copied from the
+        // corresponding method in ItemRenderer. 
+        GlStateManager.pushMatrix();
+        GlStateManager.translate( offset * 0.51f, -0.08f + equipProgress * -1.2f, -0.75f );
+        float f1 = MathHelper.sqrt( swingProgress );
+        float f2 = MathHelper.sin( f1 * (float) Math.PI );
+        float f3 = -0.5f * f2;
+        float f4 = 0.4f * MathHelper.sin( f1 * ((float) Math.PI * 2f) );
+        float f5 = -0.3f * MathHelper.sin( swingProgress * (float) Math.PI );
+        GlStateManager.translate( offset * f3, f4 - 0.3f * f2, f5 );
+        GlStateManager.rotate( f2 * -45f, 1f, 0f, 0f );
+        GlStateManager.rotate( offset * f2 * -30f, 0f, 1f, 0f );
+
+        renderPocketComputerItem( stack );
+
+        GlStateManager.popMatrix();
+    }
+
+    /**
+     * Render an item in the middle of the screen
+     *
+     * @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 ItemRenderer#renderMapFirstPerson(float, float, float)
+     */
+    private void renderItemFirstCentre( float pitch, float equipProgress, float swingProgress, ItemStack stack )
+    {
+        ItemRenderer itemRenderer = Minecraft.getMinecraft().getItemRenderer();
+
+        // Setup the appropriate transformations. This is just copied from the
+        // corresponding method in ItemRenderer.
+        float swingRt = MathHelper.sqrt( swingProgress );
+        float tX = -0.2f * MathHelper.sin( swingProgress * (float) Math.PI );
+        float tZ = -0.4f * MathHelper.sin( swingRt * (float) Math.PI );
+        GlStateManager.translate( 0f, -tX / 2f, tZ );
+        float pitchAngle = itemRenderer.getMapAngleFromPitch( pitch );
+        GlStateManager.translate( 0f, 0.04f + equipProgress * -1.2f + pitchAngle * -0.5f, -0.72f );
+        GlStateManager.rotate( pitchAngle * -85f, 1f, 0f, 0f );
+        itemRenderer.renderArms();
+        float rX = MathHelper.sin( swingRt * (float) Math.PI );
+        GlStateManager.rotate( rX * 20f, 1f, 0f, 0f );
+        GlStateManager.scale( 2f, 2f, 2f );
+
+        renderPocketComputerItem( stack );
+    }
+}

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

@@ -0,0 +1,264 @@
+package dan200.computercraft.client.render;
+
+import net.minecraft.client.renderer.block.model.BakedQuad;
+import net.minecraft.client.renderer.texture.TextureAtlasSprite;
+import net.minecraft.client.renderer.vertex.VertexFormat;
+import net.minecraft.util.EnumFacing;
+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 ];
+
+        public NormalAwareTransformer( IVertexConsumer parent, Matrix4f positionMatrix, Matrix4f normalMatrix )
+        {
+            super( parent );
+            this.positionMatrix = positionMatrix;
+            this.normalMatrix = normalMatrix;
+        }
+
+        @Override
+        public void setQuadOrientation( EnumFacing 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 class BakedQuadBuilder implements IVertexConsumer
+    {
+        private final VertexFormat format;
+
+        private final int[] vertexData;
+        private int vertexIndex = 0, elementIndex = 0;
+
+        private EnumFacing orientation;
+        private int quadTint;
+        private boolean diffuse;
+        private TextureAtlasSprite texture;
+
+        private BakedQuadBuilder( VertexFormat format )
+        {
+            this.format = format;
+            this.vertexData = new int[ format.getNextOffset() ];
+        }
+
+        @Nonnull
+        @Override
+        public VertexFormat getVertexFormat()
+        {
+            return format;
+        }
+
+        @Override
+        public void setQuadTint( int tint )
+        {
+            this.quadTint = tint;
+        }
+
+        @Override
+        public void setQuadOrientation( @Nonnull EnumFacing 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/TileEntityTurtleRenderer.java

@@ -9,7 +9,6 @@ package dan200.computercraft.client.render;
 import dan200.computercraft.api.turtle.ITurtleUpgrade;
 import dan200.computercraft.api.turtle.TurtleSide;
 import dan200.computercraft.shared.computer.core.ComputerFamily;
-import dan200.computercraft.shared.computer.core.IComputer;
 import dan200.computercraft.shared.turtle.blocks.TileTurtle;
 import dan200.computercraft.shared.turtle.entity.TurtleVisionCamera;
 import dan200.computercraft.shared.util.Holiday;
@@ -121,18 +120,22 @@ public class TileEntityTurtleRenderer extends TileEntitySpecialRenderer<TileTurt
             GlStateManager.translate( posX + offset.x, posY + offset.y, posZ + offset.z );
 
             // Render the label
-            IComputer computer = turtle.getComputer();
-            String label = (computer != null) ? computer.getLabel() : null;
+            String label = turtle.createProxy().getLabel();
             if( label != null )
             {
                 renderLabel( turtle.getAccess().getPosition(), label );
             }
 
             // Render the turtle
-            GlStateManager.translate( 0.5f, 0.0f, 0.5f );
+            GlStateManager.translate( 0.5f, 0.5f, 0.5f );
             GlStateManager.rotate( 180.0f - yaw, 0.0f, 1.0f, 0.0f );
-            GlStateManager.translate( -0.5f, 0.0f, -0.5f );
-
+            if( label != null && (label.equals( "Dinnerbone" ) || label.equals( "Grumm" )) )
+            {
+                // Flip the model and swap the cull face as winding order will have changed.
+                GlStateManager.scale( 1.0f, -1.0f, 1.0f );
+                GlStateManager.cullFace( GlStateManager.CullFace.FRONT );
+            }
+            GlStateManager.translate( -0.5f, -0.5f, -0.5f );
             // Render the turtle
             int colour;
             ComputerFamily family;
@@ -172,6 +175,7 @@ public class TileEntityTurtleRenderer extends TileEntitySpecialRenderer<TileTurt
         finally
         {
             GlStateManager.popMatrix();
+            GlStateManager.cullFace( GlStateManager.CullFace.BACK );
         }
     }
 

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

@@ -6,13 +6,10 @@ import net.minecraft.client.renderer.block.model.IBakedModel;
 import net.minecraft.client.renderer.block.model.ItemCameraTransforms;
 import net.minecraft.client.renderer.block.model.ItemOverrideList;
 import net.minecraft.client.renderer.texture.TextureAtlasSprite;
-import net.minecraft.client.renderer.vertex.VertexFormat;
-import net.minecraft.client.renderer.vertex.VertexFormatElement;
 import net.minecraft.util.EnumFacing;
 
 import javax.annotation.Nonnull;
 import javax.vecmath.Matrix4f;
-import javax.vecmath.Point3f;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
@@ -20,16 +17,17 @@ import java.util.Map;
 
 public class TurtleMultiModel implements IBakedModel
 {
-    private IBakedModel m_baseModel;
-    private IBakedModel m_overlayModel;
-    private IBakedModel m_leftUpgradeModel;
-    private Matrix4f m_leftUpgradeTransform;
-    private IBakedModel m_rightUpgradeModel;
-    private Matrix4f m_rightUpgradeTransform;
+    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 List<BakedQuad> m_generalQuads;
     private Map<EnumFacing, List<BakedQuad>> m_faceQuads;
 
-    public TurtleMultiModel( IBakedModel baseModel, IBakedModel overlayModel, IBakedModel leftUpgradeModel, Matrix4f leftUpgradeTransform, IBakedModel rightUpgradeModel, Matrix4f rightUpgradeTransform )
+    public TurtleMultiModel( IBakedModel baseModel, IBakedModel overlayModel, Matrix4f generalTransform, IBakedModel leftUpgradeModel, Matrix4f leftUpgradeTransform, IBakedModel rightUpgradeModel, Matrix4f rightUpgradeTransform )
     {
         // Get the models
         m_baseModel = baseModel;
@@ -38,6 +36,7 @@ public class TurtleMultiModel implements IBakedModel
         m_leftUpgradeTransform = leftUpgradeTransform;
         m_rightUpgradeModel = rightUpgradeModel;
         m_rightUpgradeTransform = rightUpgradeTransform;
+        m_generalTransform = generalTransform;
         m_generalQuads = null;
         m_faceQuads = new HashMap<>();
     }
@@ -48,51 +47,52 @@ public class TurtleMultiModel implements IBakedModel
     {
         if( side != null )
         {
-            if( !m_faceQuads.containsKey( side ) )
-            {
-                ArrayList<BakedQuad> quads = new ArrayList<>();
-                if( m_overlayModel != null )
-                {
-                    quads.addAll( m_overlayModel.getQuads( state, side, rand ) );
-                }
-                if( m_leftUpgradeModel != null )
-                {
-                    quads.addAll( transformQuads( m_leftUpgradeModel.getQuads( state, side, rand ), m_leftUpgradeTransform ) );
-                }
-                if( m_rightUpgradeModel != null )
-                {
-                    quads.addAll( transformQuads( m_rightUpgradeModel.getQuads( state, side, rand ), m_rightUpgradeTransform ) );
-                }
-                quads.trimToSize();
-                m_faceQuads.put( side, quads );
-            }
+            if( !m_faceQuads.containsKey( side ) ) m_faceQuads.put( side, buildQuads( state, side, rand ) );
             return m_faceQuads.get( side );
         }
         else
         {
-            if( m_generalQuads == null )
-            {
-                ArrayList<BakedQuad> quads = new ArrayList<>();
-                quads.addAll( m_baseModel.getQuads( state, side, rand ) );
-                if( m_overlayModel != null )
-                {
-                    quads.addAll( m_overlayModel.getQuads( state, side, rand ) );
-                }
-                if( m_leftUpgradeModel != null )
-                {
-                    quads.addAll( transformQuads( m_leftUpgradeModel.getQuads( state, side, rand ), m_leftUpgradeTransform ) );
-                }
-                if( m_rightUpgradeModel != null )
-                {
-                    quads.addAll( transformQuads( m_rightUpgradeModel.getQuads( state, side, rand ), m_rightUpgradeTransform ) );
-                }
-                quads.trimToSize();
-                m_generalQuads = quads;
-            }
+            if( m_generalQuads == null ) m_generalQuads = buildQuads( state, side, rand );
             return m_generalQuads;
         }
     }
 
+    private List<BakedQuad> buildQuads( IBlockState state, EnumFacing side, long rand )
+    {
+        ArrayList<BakedQuad> quads = new ArrayList<>();
+        ModelTransformer.transformQuadsTo( quads, m_baseModel.getQuads( state, side, rand ), m_generalTransform );
+        if( m_overlayModel != null )
+        {
+            ModelTransformer.transformQuadsTo( quads, m_overlayModel.getQuads( state, side, rand ), m_generalTransform );
+        }
+        if( m_overlayModel != null )
+        {
+            ModelTransformer.transformQuadsTo( quads, m_overlayModel.getQuads( state, side, rand ), 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 ), 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 ), upgradeTransform );
+        }
+        quads.trimToSize();
+        return quads;
+    }
+
     @Override
     public boolean isAmbientOcclusion()
     {
@@ -132,63 +132,4 @@ public class TurtleMultiModel implements IBakedModel
     {
         return ItemOverrideList.NONE;
     }
-
-    private List<BakedQuad> transformQuads( List<BakedQuad> input, Matrix4f transform )
-    {
-        if( transform == null || input.size() == 0 )
-        {
-            return input;
-        }
-        else
-        {
-            List<BakedQuad> output = new ArrayList<>( input.size() );
-            for( BakedQuad quad : input )
-            {
-                output.add( transformQuad( quad, transform ) );
-            }
-            return output;
-        }
-    }
-
-    private BakedQuad transformQuad( BakedQuad quad, Matrix4f transform )
-    {
-        int[] vertexData = quad.getVertexData().clone();
-        int offset = 0;
-        BakedQuad copy = new BakedQuad( vertexData, -1, quad.getFace(), quad.getSprite(), quad.shouldApplyDiffuseLighting(), quad.getFormat() );
-        VertexFormat format = copy.getFormat();
-        for( int i=0; i<format.getElementCount(); ++i ) // For each vertex element
-        {
-            VertexFormatElement element = format.getElement( i );
-            if( element.isPositionElement() &&
-                element.getType() == VertexFormatElement.EnumType.FLOAT &&
-                element.getElementCount() == 3 ) // When we find a position element
-            {
-                for( int j=0; j<4; ++j ) // For each corner of the quad
-                {
-                    int start = offset + j * format.getNextOffset();
-                    if( (start % 4) == 0 )
-                    {
-                        start = start / 4;
-
-                        // Extract the position
-                        Point3f pos = new Point3f(
-                            Float.intBitsToFloat( vertexData[ start ] ),
-                            Float.intBitsToFloat( vertexData[ start + 1 ] ),
-                            Float.intBitsToFloat( vertexData[ start + 2 ] )
-                        );
-
-                        // Transform the position
-                        transform.transform( pos );
-
-                        // Insert the position
-                        vertexData[ start ] = Float.floatToRawIntBits( pos.x );
-                        vertexData[ start + 1 ] = Float.floatToRawIntBits( pos.y );
-                        vertexData[ start + 2 ] = Float.floatToRawIntBits( pos.z );
-                    }
-                }
-            }
-            offset += element.getSize();
-        }
-        return copy;
-    }
 }

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

@@ -35,6 +35,19 @@ import java.util.List;
 
 public class TurtleSmartItemModel implements IBakedModel, IResourceManagerReloadListener
 {
+    private static final Matrix4f s_identity, s_flip;
+
+    static
+    {
+        s_identity = new Matrix4f();
+        s_identity.setIdentity();
+
+        s_flip = new Matrix4f();
+        s_flip.setIdentity();
+        s_flip.m11 = -1; // Flip on the y axis
+        s_flip.m13 = 1; // Models go from (0,0,0) to (1,1,1), so push back up.
+    }
+
     private static class TurtleModelCombination
     {
         public final ComputerFamily m_family;
@@ -43,8 +56,9 @@ public class TurtleSmartItemModel implements IBakedModel, IResourceManagerReload
         public final ITurtleUpgrade m_rightUpgrade;
         public final ResourceLocation m_overlay;
         public final boolean m_christmas;
+        public final boolean m_flip;
 
-        public TurtleModelCombination( ComputerFamily family, boolean colour, ITurtleUpgrade leftUpgrade, ITurtleUpgrade rightUpgrade, ResourceLocation overlay, boolean christmas )
+        public TurtleModelCombination( ComputerFamily family, boolean colour, ITurtleUpgrade leftUpgrade, ITurtleUpgrade rightUpgrade, ResourceLocation overlay, boolean christmas, boolean flip )
         {
             m_family = family;
             m_colour = colour;
@@ -52,22 +66,26 @@ public class TurtleSmartItemModel implements IBakedModel, IResourceManagerReload
             m_rightUpgrade = rightUpgrade;
             m_overlay = overlay;
             m_christmas = christmas;
+            m_flip = flip;
         }
 
         @Override
         public boolean equals( Object other )
         {
-            if( other == this ) {
+            if( other == this )
+            {
                 return true;
             }
-            if( other instanceof TurtleModelCombination ) {
-                TurtleModelCombination otherCombo = (TurtleModelCombination)other;
+            if( other instanceof TurtleModelCombination )
+            {
+                TurtleModelCombination otherCombo = (TurtleModelCombination) other;
                 if( otherCombo.m_family == m_family &&
                     otherCombo.m_colour == m_colour &&
                     otherCombo.m_leftUpgrade == m_leftUpgrade &&
                     otherCombo.m_rightUpgrade == m_rightUpgrade &&
                     Objects.equal( otherCombo.m_overlay, m_overlay ) &&
-                    otherCombo.m_christmas == m_christmas )
+                    otherCombo.m_christmas == m_christmas &&
+                    otherCombo.m_flip == m_flip )
                 {
                     return true;
                 }
@@ -86,10 +104,11 @@ public class TurtleSmartItemModel implements IBakedModel, IResourceManagerReload
             result = prime * result + (m_rightUpgrade != null ? m_rightUpgrade.hashCode() : 0);
             result = prime * result + (m_overlay != null ? m_overlay.hashCode() : 0);
             result = prime * result + (m_christmas ? 1 : 0);
+            result = prime * result + (m_flip ? 1 : 0);
             return result;
         }
     }
-    
+
     private HashMap<TurtleModelCombination, IBakedModel> m_cachedModels;
     private ItemOverrideList m_overrides;
     private final TurtleModelCombination m_defaultCombination;
@@ -97,12 +116,12 @@ public class TurtleSmartItemModel implements IBakedModel, IResourceManagerReload
     public TurtleSmartItemModel()
     {
         m_cachedModels = new HashMap<>();
-        m_defaultCombination = new TurtleModelCombination( ComputerFamily.Normal, false, null, null, null, false );
+        m_defaultCombination = new TurtleModelCombination( ComputerFamily.Normal, false, null, null, null, false, false );
         m_overrides = new ItemOverrideList( new ArrayList<>() )
         {
             @Nonnull
             @Override
-            public IBakedModel handleItemState( @Nonnull IBakedModel originalModel, @Nonnull ItemStack stack, @Nullable World world, @Nullable EntityLivingBase entity)
+            public IBakedModel handleItemState( @Nonnull IBakedModel originalModel, @Nonnull ItemStack stack, @Nullable World world, @Nullable EntityLivingBase entity )
             {
                 ItemTurtleBase turtle = (ItemTurtleBase) stack.getItem();
                 ComputerFamily family = turtle.getFamily( stack );
@@ -111,7 +130,9 @@ public class TurtleSmartItemModel implements IBakedModel, IResourceManagerReload
                 ITurtleUpgrade rightUpgrade = turtle.getUpgrade( stack, TurtleSide.Right );
                 ResourceLocation overlay = turtle.getOverlay( stack );
                 boolean christmas = HolidayUtil.getCurrentHoliday() == Holiday.Christmas;
-                TurtleModelCombination combo = new TurtleModelCombination( family, colour != -1, leftUpgrade, rightUpgrade, overlay, christmas );
+                String label = turtle.getLabel( stack );
+                boolean flip = label != null && (label.equals( "Dinnerbone" ) || label.equals( "Grumm" ));
+                TurtleModelCombination combo = new TurtleModelCombination( family, colour != -1, leftUpgrade, rightUpgrade, overlay, christmas, flip );
                 if( m_cachedModels.containsKey( combo ) )
                 {
                     return m_cachedModels.get( combo );
@@ -147,27 +168,24 @@ public class TurtleSmartItemModel implements IBakedModel, IResourceManagerReload
         ModelResourceLocation overlayModelLocation = TileEntityTurtleRenderer.getTurtleOverlayModel( combo.m_family, combo.m_overlay, combo.m_christmas );
         IBakedModel baseModel = modelManager.getModel( baseModelLocation );
         IBakedModel overlayModel = (overlayModelLocation != null) ? modelManager.getModel( baseModelLocation ) : null;
+        Matrix4f transform = combo.m_flip ? s_flip : s_identity;
         Pair<IBakedModel, Matrix4f> leftModel = (combo.m_leftUpgrade != null) ? combo.m_leftUpgrade.getModel( null, TurtleSide.Left ) : null;
         Pair<IBakedModel, Matrix4f> rightModel = (combo.m_rightUpgrade != null) ? combo.m_rightUpgrade.getModel( null, TurtleSide.Right ) : null;
         if( leftModel != null && rightModel != null )
         {
-            return new TurtleMultiModel( baseModel, overlayModel, leftModel.getLeft(), leftModel.getRight(), rightModel.getLeft(), rightModel.getRight() );
+            return new TurtleMultiModel( baseModel, overlayModel, transform, leftModel.getLeft(), leftModel.getRight(), rightModel.getLeft(), rightModel.getRight() );
         }
         else if( leftModel != null )
         {
-            return new TurtleMultiModel( baseModel, overlayModel, leftModel.getLeft(), leftModel.getRight(), null, null );
+            return new TurtleMultiModel( baseModel, overlayModel, transform, leftModel.getLeft(), leftModel.getRight(), null, null );
         }
         else if( rightModel != null )
         {
-            return new TurtleMultiModel( baseModel, overlayModel, null, null, rightModel.getLeft(), rightModel.getRight() );
-        }
-        else if( overlayModel != null )
-        {
-            return new TurtleMultiModel( baseModel, overlayModel, null, null, null, null );
+            return new TurtleMultiModel( baseModel, overlayModel, transform, null, null, rightModel.getLeft(), rightModel.getRight() );
         }
         else
         {
-            return baseModel;
+            return new TurtleMultiModel( baseModel, overlayModel, transform, null, null, null, null );
         }
     }
 

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

@@ -6,6 +6,7 @@
 
 package dan200.computercraft.core.apis;
 
+import dan200.computercraft.api.lua.ILuaAPI;
 import dan200.computercraft.api.lua.ILuaContext;
 import dan200.computercraft.api.lua.ILuaObject;
 import dan200.computercraft.api.lua.LuaException;
@@ -100,21 +101,6 @@ public class BufferAPI implements ILuaAPI
         };
     }
 
-    @Override
-    public void startup()
-    {
-    }
-
-    @Override
-    public void advance( double _dt )
-    {
-    }
-
-    @Override
-    public void shutdown()
-    {
-    }
-
     @Nonnull
     @Override
     public String[] getMethodNames()

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

@@ -0,0 +1,155 @@
+package dan200.computercraft.core.apis;
+
+import dan200.computercraft.api.filesystem.IMount;
+import dan200.computercraft.api.filesystem.IWritableMount;
+import dan200.computercraft.api.peripheral.IComputerAccess;
+import dan200.computercraft.core.filesystem.FileSystem;
+import dan200.computercraft.core.filesystem.FileSystemException;
+
+import javax.annotation.Nonnull;
+import java.util.HashSet;
+import java.util.Set;
+
+public abstract class ComputerAccess implements IComputerAccess
+{
+    private final IAPIEnvironment m_environment;
+    private final Set<String> m_mounts = new HashSet<>();
+
+    protected ComputerAccess( IAPIEnvironment m_environment )
+    {
+        this.m_environment = m_environment;
+    }
+
+    public void unmountAll()
+    {
+        FileSystem fileSystem = m_environment.getFileSystem();
+        for( String m_mount : m_mounts )
+        {
+            fileSystem.unmount( m_mount );
+        }
+        m_mounts.clear();
+    }
+
+    @Override
+    public String mount( @Nonnull String desiredLoc, @Nonnull IMount mount )
+    {
+        return mount( desiredLoc, mount, getAttachmentName() );
+    }
+
+    @Override
+    public synchronized String mount( @Nonnull String desiredLoc, @Nonnull IMount mount, @Nonnull String driveName )
+    {
+        // Mount the location
+        String location;
+        FileSystem fileSystem = m_environment.getFileSystem();
+        if( fileSystem == null )
+        {
+            throw new IllegalStateException( "File system has not been created" );
+        }
+
+        synchronized( fileSystem )
+        {
+            location = findFreeLocation( desiredLoc );
+            if( location != null )
+            {
+                try
+                {
+                    fileSystem.mount( driveName, location, mount );
+                }
+                catch( FileSystemException ignored )
+                {
+                }
+            }
+        }
+        if( location != null )
+        {
+            m_mounts.add( location );
+        }
+        return location;
+    }
+
+    @Override
+    public String mountWritable( @Nonnull String desiredLoc, @Nonnull IWritableMount mount )
+    {
+        return mountWritable( desiredLoc, mount, getAttachmentName() );
+    }
+
+    @Override
+    public synchronized String mountWritable( @Nonnull String desiredLoc, @Nonnull IWritableMount mount, @Nonnull String driveName )
+    {
+        // Mount the location
+        String location;
+        FileSystem fileSystem = m_environment.getFileSystem();
+        if( fileSystem == null )
+        {
+            throw new IllegalStateException( "File system has not been created" );
+        }
+
+        synchronized( fileSystem )
+        {
+            location = findFreeLocation( desiredLoc );
+            if( location != null )
+            {
+                try
+                {
+                    fileSystem.mountWritable( driveName, location, mount );
+                }
+                catch( FileSystemException ignored )
+                {
+                }
+            }
+        }
+        if( location != null )
+        {
+            m_mounts.add( location );
+        }
+        return location;
+    }
+
+    @Override
+    public void unmount( String location )
+    {
+        if( location != null )
+        {
+            if( !m_mounts.contains( location ) )
+            {
+                throw new RuntimeException( "You didn't mount this location" );
+            }
+
+            m_environment.getFileSystem().unmount( location );
+            m_mounts.remove( location );
+        }
+    }
+
+    @Override
+    public int getID()
+    {
+        return m_environment.getComputerID();
+    }
+
+    @Override
+    public void queueEvent( @Nonnull final String event, final Object[] arguments )
+    {
+        m_environment.queueEvent( event, arguments );
+    }
+
+    private String findFreeLocation( String desiredLoc )
+    {
+        try
+        {
+            FileSystem fileSystem = m_environment.getFileSystem();
+            if( !fileSystem.exists( desiredLoc ) )
+            {
+                return desiredLoc;
+            }
+
+            // We used to check foo2,foo3,foo4,etc here
+            // but the disk drive does this itself now
+            return null;
+        }
+        catch( FileSystemException e )
+        {
+            return null;
+        }
+    }
+}

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

@@ -6,6 +6,7 @@
 
 package dan200.computercraft.core.apis;
 
+import dan200.computercraft.api.lua.ILuaAPI;
 import dan200.computercraft.api.lua.ILuaContext;
 import dan200.computercraft.api.lua.LuaException;
 import dan200.computercraft.core.apis.handles.BinaryInputHandle;
@@ -48,11 +49,6 @@ public class FSAPI implements ILuaAPI
         m_fileSystem = m_env.getFileSystem();
     }
 
-    @Override
-    public void advance( double _dt )
-    {
-    }
-    
     @Override
     public void shutdown( )
     {

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

@@ -7,6 +7,7 @@
 package dan200.computercraft.core.apis;
 
 import dan200.computercraft.ComputerCraft;
+import dan200.computercraft.api.lua.ILuaAPI;
 import dan200.computercraft.api.lua.ILuaContext;
 import dan200.computercraft.api.lua.LuaException;
 import dan200.computercraft.core.apis.http.*;
@@ -43,12 +44,7 @@ public class HTTPAPI implements ILuaAPI
     }
 
     @Override
-    public void startup( )
-    {
-    }
-
-    @Override
-    public void advance( double _dt )
+    public void update()
     {
         // Wait for all of our http requests
         synchronized( m_httpTasks )

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

@@ -1,17 +0,0 @@
-/*
- * This file is part of ComputerCraft - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2017. Do not distribute without permission.
- * Send enquiries to dratcliffe@gmail.com
- */
-
-package dan200.computercraft.core.apis;
-import dan200.computercraft.api.lua.ILuaObject;
-
-public interface ILuaAPI extends ILuaObject
-{
-    String[] getNames();
-
-    void startup(); // LT
-    void advance( double _dt ); // MT
-    void shutdown(); // LT
-}

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

@@ -6,6 +6,7 @@
 
 package dan200.computercraft.core.apis;
 
+import dan200.computercraft.api.lua.ILuaAPI;
 import dan200.computercraft.api.lua.ILuaContext;
 import dan200.computercraft.api.lua.LuaException;
 import dan200.computercraft.shared.util.StringUtil;
@@ -102,7 +103,7 @@ public class OSAPI implements ILuaAPI
     }
     
     @Override
-    public void advance( double dt )
+    public void update()
     {
         synchronized( m_timers )
         {

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

@@ -8,24 +8,25 @@ package dan200.computercraft.core.apis;
 
 import dan200.computercraft.api.filesystem.IMount;
 import dan200.computercraft.api.filesystem.IWritableMount;
+import dan200.computercraft.api.lua.ILuaAPI;
 import dan200.computercraft.api.lua.ILuaContext;
 import dan200.computercraft.api.lua.LuaException;
-import dan200.computercraft.api.peripheral.IComputerAccess;
 import dan200.computercraft.api.peripheral.IPeripheral;
 import dan200.computercraft.core.computer.Computer;
 import dan200.computercraft.core.computer.ComputerThread;
 import dan200.computercraft.core.computer.ITask;
 import dan200.computercraft.core.filesystem.FileSystem;
-import dan200.computercraft.core.filesystem.FileSystemException;
 
 import javax.annotation.Nonnull;
-import java.util.*;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.Map;
 
 import static dan200.computercraft.core.apis.ArgumentHelper.getString;
 
 public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChangeListener
 {
-    private class PeripheralWrapper implements IComputerAccess
+    private class PeripheralWrapper extends ComputerAccess
     {
         private final String m_side;
         private final IPeripheral m_peripheral;
@@ -35,10 +36,9 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
         private Map<String, Integer> m_methodMap;
         private boolean m_attached;
 
-        private Set<String> m_mounts;
-
         public PeripheralWrapper( IPeripheral peripheral, String side )
         {
+            super(m_environment);
             m_side = side;
             m_peripheral = peripheral;
             m_attached = false;
@@ -54,8 +54,6 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
                     m_methodMap.put( m_methods[i], i );
                 }
             }
-
-            m_mounts = new HashSet<>();
         }
 
         public IPeripheral getPeripheral()
@@ -91,14 +89,11 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
 
             synchronized( this )
             {
-                m_attached = false;
                 // Unmount everything the detach function forgot to do
-                for( String m_mount : m_mounts )
-                {
-                    m_fileSystem.unmount( m_mount );
-                }
-                m_mounts.clear();
+                unmountAll();
             }
+
+            m_attached = false;
         }
 
         public Object[] call( ILuaContext context, String methodName, Object[] arguments ) throws LuaException, InterruptedException
@@ -122,13 +117,6 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
         }
 
         // IComputerAccess implementation
-
-        @Override
-        public String mount( @Nonnull String desiredLoc, @Nonnull IMount mount )
-        {
-            return mount( desiredLoc, mount, m_side );
-        }
-
         @Override
         public synchronized String mount( @Nonnull String desiredLoc, @Nonnull IMount mount, @Nonnull String driveName )
         {
@@ -137,31 +125,7 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
                 throw new RuntimeException( "You are not attached to this Computer" );
             }
 
-            // Mount the location
-            String location;
-            synchronized( m_fileSystem )
-            {
-                location = findFreeLocation( desiredLoc );
-                if( location != null )
-                {
-                    try {
-                        m_fileSystem.mount( driveName, location, mount );
-                    } catch( FileSystemException e ) {
-                        // fail and return null
-                    }
-                }
-            }
-            if( location != null )
-            {
-                m_mounts.add( location );
-            }
-            return location;
-        }
-
-        @Override
-        public String mountWritable( @Nonnull String desiredLoc, @Nonnull IWritableMount mount )
-        {
-            return mountWritable( desiredLoc, mount, m_side );
+            return super.mount( desiredLoc, mount, driveName );
         }
 
         @Override
@@ -172,68 +136,46 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
                 throw new RuntimeException( "You are not attached to this Computer" );
             }
 
-            // Mount the location
-            String location;
-            synchronized( m_fileSystem )
-            {
-                location = findFreeLocation( desiredLoc );
-                if( location != null )
-                {
-                    try {
-                        m_fileSystem.mountWritable( driveName, location, mount );
-                    } catch( FileSystemException e ) {
-                        // fail and return null
-                    }
-                }
-            }
-            if( location != null )
-            {
-                m_mounts.add( location );
-            }
-            return location;
+            return super.mountWritable( desiredLoc, mount, driveName );
         }
 
         @Override
         public synchronized void unmount( String location )
         {
-            if( !m_attached ) {
+            if( !m_attached )
+            {
                 throw new RuntimeException( "You are not attached to this Computer" );
             }
 
-            if( location != null )
-            {
-                if( !m_mounts.contains( location ) ) {
-                    throw new RuntimeException( "You didn't mount this location" );
-                }
-
-                m_fileSystem.unmount( location );
-                m_mounts.remove( location );
-            }
+            super.unmount( location );
         }
 
         @Override
         public int getID()
         {
-            if( !m_attached ) {
+            if( !m_attached )
+            {
                 throw new RuntimeException( "You are not attached to this Computer" );
             }
-            return m_environment.getComputerID();
+            return super.getID();
         }
 
         @Override
         public void queueEvent( @Nonnull final String event, final Object[] arguments )
         {
-            if( !m_attached ) {
+            if( !m_attached )
+            {
                 throw new RuntimeException( "You are not attached to this Computer" );
             }
-            m_environment.queueEvent( event, arguments );
+            super.queueEvent( event, arguments );
         }
 
         @Nonnull
         @Override
         public String getAttachmentName()
         {
-            if( !m_attached ) {
+            if( !m_attached )
+            {
                 throw new RuntimeException( "You are not attached to this Computer" );
             }
             return m_side;
@@ -356,11 +298,6 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
         }
     }
 
-    @Override
-    public void advance( double _dt )
-    {
-    }
-
     @Override
     public void shutdown( )
     {
@@ -504,25 +441,4 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
         }
         return -1;
     }
-
-    private String findFreeLocation( String desiredLoc )
-    {
-        try
-        {
-            synchronized( m_fileSystem )
-            {
-                if( !m_fileSystem.exists( desiredLoc ) )
-                {
-                    return desiredLoc;
-                }
-                // We used to check foo2,foo3,foo4,etc here
-                // but the disk drive does this itself now
-                return null;
-            }
-        }
-        catch( FileSystemException e )
-        {
-            return null;
-        }
-    }
 }

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

@@ -6,6 +6,7 @@
 
 package dan200.computercraft.core.apis;
 
+import dan200.computercraft.api.lua.ILuaAPI;
 import dan200.computercraft.api.lua.ILuaContext;
 import dan200.computercraft.api.lua.LuaException;
 import dan200.computercraft.core.computer.Computer;
@@ -33,21 +34,6 @@ public class RedstoneAPI implements ILuaAPI
         };
     }
 
-    @Override
-    public void startup( )
-    {
-    }
-
-    @Override
-    public void advance( double _dt )
-    {
-    }
-    
-    @Override
-    public void shutdown( )
-    {
-    }
-
     @Nonnull
     @Override
     public String[] getMethodNames()

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

@@ -6,6 +6,7 @@
 
 package dan200.computercraft.core.apis;
 
+import dan200.computercraft.api.lua.ILuaAPI;
 import dan200.computercraft.api.lua.ILuaContext;
 import dan200.computercraft.api.lua.LuaException;
 import dan200.computercraft.core.computer.IComputerEnvironment;
@@ -36,21 +37,6 @@ public class TermAPI implements ILuaAPI
         };
     }
 
-    @Override
-    public void startup( )
-    {
-    }
-
-    @Override
-    public void advance( double _dt )
-    {
-    }
-    
-    @Override
-    public void shutdown( )
-    {
-    }
-
     @Nonnull
     @Override
     public String[] getMethodNames()

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

@@ -8,16 +8,20 @@ package dan200.computercraft.core.computer;
 
 import com.google.common.base.Objects;
 import dan200.computercraft.ComputerCraft;
+import dan200.computercraft.api.filesystem.IFileSystem;
 import dan200.computercraft.api.filesystem.IMount;
 import dan200.computercraft.api.filesystem.IWritableMount;
+import dan200.computercraft.api.lua.*;
 import dan200.computercraft.api.peripheral.IPeripheral;
 import dan200.computercraft.core.apis.*;
 import dan200.computercraft.core.filesystem.FileSystem;
 import dan200.computercraft.core.filesystem.FileSystemException;
-import dan200.computercraft.core.lua.ILuaMachine;
 import dan200.computercraft.core.lua.CobaltLuaMachine;
+import dan200.computercraft.core.lua.ILuaMachine;
 import dan200.computercraft.core.terminal.Terminal;
 
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.ArrayList;
@@ -173,7 +177,91 @@ public class Computer
             }
         }
     }
-    
+
+    private static class ComputerSystem extends ComputerAccess implements IComputerSystem
+    {
+        private final IAPIEnvironment m_environment;
+
+        private ComputerSystem( IAPIEnvironment m_environment )
+        {
+            super( m_environment );
+            this.m_environment = m_environment;
+        }
+
+        @Nonnull
+        @Override
+        public String getAttachmentName()
+        {
+            return "computer";
+        }
+
+        @Nullable
+        @Override
+        public IFileSystem getFileSystem()
+        {
+            FileSystem fs = m_environment.getFileSystem();
+            return fs == null ? null : fs.getMountWrapper();
+        }
+
+        @Nullable
+        @Override
+        public String getLabel()
+        {
+            return m_environment.getLabel();
+        }
+    }
+
+    private static class APIWrapper implements ILuaAPI
+    {
+        private final ILuaAPI delegate;
+        private final ComputerSystem system;
+
+        private APIWrapper( ILuaAPI delegate, ComputerSystem system )
+        {
+            this.delegate = delegate;
+            this.system = system;
+        }
+
+        @Override
+        public String[] getNames()
+        {
+            return delegate.getNames();
+        }
+
+        @Override
+        public void startup()
+        {
+            delegate.startup();
+        }
+
+        @Override
+        public void update()
+        {
+            delegate.update();
+        }
+
+        @Override
+        public void shutdown()
+        {
+            delegate.shutdown();
+            system.unmountAll();
+        }
+
+        @Nonnull
+        @Override
+        public String[] getMethodNames()
+        {
+            return delegate.getMethodNames();
+        }
+
+        @Nullable
+        @Override
+        public Object[] callMethod( @Nonnull ILuaContext context, int method, @Nonnull Object[] arguments ) throws LuaException, InterruptedException
+        {
+            return delegate.callMethod( context, method, arguments );
+        }
+    }
+
     private static IMount s_romMount = null;
 
     private int m_id;
@@ -371,7 +459,7 @@ public class Computer
                 {
                     for(ILuaAPI api : m_apis)
                     {
-                        api.advance( _dt );
+                        api.update();
                     }
                 }
             }
@@ -420,14 +508,13 @@ public class Computer
         }
     }
     
-    public boolean pollChanged()
+    public boolean pollAndResetChanged()
     {
-        return m_externalOutputChanged;
-    }
-
-    public void clearChanged()
-    {
-        m_externalOutputChanged = false;
+        synchronized(this) {
+            boolean changed = m_externalOutputChanged;
+            m_externalOutputChanged = false;
+            return changed;
+        }
     }
 
     public boolean isBlinking()
@@ -616,6 +703,16 @@ public class Computer
         {
             m_apis.add( new HTTPAPI( m_apiEnvironment ) );
         }
+
+        for( ILuaAPIFactory factory : ComputerCraft.getAPIFactories() )
+        {
+            ComputerSystem system = new ComputerSystem( m_apiEnvironment );
+            ILuaAPI api = factory.create( system );
+            if( api != null )
+            {
+                m_apis.add( api );
+            }
+        }
     }
     
     private void initLua()
@@ -687,6 +784,7 @@ public class Computer
                 return;
             }
             m_state = State.Starting;
+            m_externalOutputChanged = true;
             m_ticksSinceStart = 0;
         }
         
@@ -746,6 +844,7 @@ public class Computer
                     
                     // Start a new state
                     m_state = State.Running;
+                    m_externalOutputChanged = true;
                     synchronized( m_machine )
                     {
                         m_machine.handleEvent( null, null );
@@ -764,6 +863,7 @@ public class Computer
                 return;
             }
             m_state = State.Stopping;
+            m_externalOutputChanged = true;
         }
         
         // Turn the computercraft off
@@ -788,7 +888,7 @@ public class Computer
                     // Shutdown our APIs
                     synchronized( m_apis )
                     {
-                        for(ILuaAPI api : m_apis)
+                        for( ILuaAPI api : m_apis )
                         {
                             api.shutdown();
                         }
@@ -827,6 +927,7 @@ public class Computer
                     }
 
                     m_state = State.Off;
+                    m_externalOutputChanged = true;
                     if( reboot )
                     {
                         m_startRequested = true;

src/main/java/dan200/computercraft/core/filesystem/FileSystem.java

@@ -7,6 +7,7 @@
 package dan200.computercraft.core.filesystem;
 
 import dan200.computercraft.ComputerCraft;
+import dan200.computercraft.api.filesystem.IFileSystem;
 import dan200.computercraft.api.filesystem.IMount;
 import dan200.computercraft.api.filesystem.IWritableMount;
 
@@ -290,6 +291,7 @@ public class FileSystem
         }
     }
 
+    private final FileSystemMount m_wrapper = new FileSystemMount( this );
     private final Map<String, MountWrapper> m_mounts = new HashMap<>();
     private final Set<Closeable> m_openFiles = Collections.newSetFromMap( new WeakHashMap<Closeable, Boolean>() );
     
@@ -734,6 +736,11 @@ public class FileSystem
         return match;
     }
 
+    public IFileSystem getMountWrapper()
+    {
+        return m_wrapper;
+    }
+
     private static String sanitizePath( String path )
     {
         return sanitizePath( path, false );

src/main/java/dan200/computercraft/core/filesystem/FileSystemMount.java

@@ -0,0 +1,185 @@
+package dan200.computercraft.core.filesystem;
+
+import dan200.computercraft.api.filesystem.IFileSystem;
+
+import javax.annotation.Nonnull;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.util.Collections;
+import java.util.List;
+
+public class FileSystemMount implements IFileSystem
+{
+    private final FileSystem m_filesystem;
+
+    public FileSystemMount( FileSystem m_filesystem )
+    {
+        this.m_filesystem = m_filesystem;
+    }
+
+    @Override
+    public void makeDirectory( @Nonnull String path ) throws IOException
+    {
+        try
+        {
+            m_filesystem.makeDir( path );
+        }
+        catch( FileSystemException e )
+        {
+            throw new IOException( e.getMessage() );
+        }
+    }
+
+    @Override
+    public void delete( @Nonnull String path ) throws IOException
+    {
+        try
+        {
+            m_filesystem.delete( path );
+        }
+        catch( FileSystemException e )
+        {
+            throw new IOException( e.getMessage() );
+        }
+    }
+
+    @Nonnull
+    @Override
+    public OutputStream openForWrite( @Nonnull String path ) throws IOException
+    {
+        try
+        {
+            return m_filesystem.openForWrite( path, false );
+        }
+        catch( FileSystemException e )
+        {
+            throw new IOException( e.getMessage() );
+        }
+    }
+
+    @Nonnull
+    @Override
+    public OutputStream openForAppend( @Nonnull String path ) throws IOException
+    {
+        try
+        {
+            return m_filesystem.openForWrite( path, true );
+        }
+        catch( FileSystemException e )
+        {
+            throw new IOException( e.getMessage() );
+        }
+    }
+
+    @Override
+    public long getRemainingSpace() throws IOException
+    {
+        try
+        {
+            return m_filesystem.getFreeSpace( "/" );
+        }
+        catch( FileSystemException e )
+        {
+            throw new IOException( e.getMessage() );
+        }
+    }
+
+    @Override
+    public boolean exists( @Nonnull String path ) throws IOException
+    {
+        try
+        {
+            return m_filesystem.exists( path );
+        }
+        catch( FileSystemException e )
+        {
+            throw new IOException( e.getMessage() );
+        }
+    }
+
+    @Override
+    public boolean isDirectory( @Nonnull String path ) throws IOException
+    {
+        try
+        {
+            return m_filesystem.exists( path );
+        }
+        catch( FileSystemException e )
+        {
+            throw new IOException( e.getMessage() );
+        }
+    }
+
+    @Override
+    public void list( @Nonnull String path, @Nonnull List<String> contents ) throws IOException
+    {
+        try
+        {
+            Collections.addAll( contents, m_filesystem.list( path ) );
+        }
+        catch( FileSystemException e )
+        {
+            throw new IOException( e.getMessage() );
+        }
+    }
+
+    @Override
+    public long getSize( @Nonnull String path ) throws IOException
+    {
+        try
+        {
+            return m_filesystem.getSize( path );
+        }
+        catch( FileSystemException e )
+        {
+            throw new IOException( e.getMessage() );
+        }
+    }
+
+    @Nonnull
+    @Override
+    public InputStream openForRead( @Nonnull String path ) throws IOException
+    {
+        try
+        {
+            return m_filesystem.openForRead( path );
+        }
+        catch( FileSystemException e )
+        {
+            throw new IOException( e.getMessage() );
+        }
+    }
+
+    @Override
+    public String combine( String path, String child )
+    {
+        return m_filesystem.combine( path, child );
+    }
+
+    @Override
+    public void copy( String from, String to ) throws IOException
+    {
+        try
+        {
+            m_filesystem.copy( from, to );
+        }
+        catch( FileSystemException e )
+        {
+            throw new IOException( e.getMessage() );
+        }
+    }
+
+    @Override
+    public void move( String from, String to ) throws IOException
+    {
+        try
+        {
+            m_filesystem.move( from, to );
+        }
+        catch( FileSystemException e )
+        {
+            throw new IOException( e.getMessage() );
+        }
+    }
+}

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

@@ -11,7 +11,7 @@ import dan200.computercraft.api.lua.ILuaContext;
 import dan200.computercraft.api.lua.ILuaObject;
 import dan200.computercraft.api.lua.ILuaTask;
 import dan200.computercraft.api.lua.LuaException;
-import dan200.computercraft.core.apis.ILuaAPI;
+import dan200.computercraft.api.lua.ILuaAPI;
 import dan200.computercraft.core.computer.Computer;
 import dan200.computercraft.core.computer.ITask;
 import dan200.computercraft.core.computer.MainThread;

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

@@ -5,7 +5,7 @@
  */
 
 package dan200.computercraft.core.lua;
-import dan200.computercraft.core.apis.ILuaAPI;
+import dan200.computercraft.api.lua.ILuaAPI;
 
 import java.io.InputStream;
 import java.io.OutputStream;

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

@@ -241,10 +241,9 @@ public abstract class BlockGeneric extends Block implements
             if( collision.size() > 0 )
             {
                 AxisAlignedBB aabb = collision.get( 0 );
-                for (int i=1; i<collision.size(); ++i )
+                for( int i = 1; i < collision.size(); i++ )
                 {
-                    AxisAlignedBB other = collision.get( 1 );
-                    aabb = aabb.union( other );
+                    aabb = aabb.union( collision.get( i ) );
                 }
                 return aabb;
             }

src/main/java/dan200/computercraft/shared/computer/apis/CommandAPI.java

@@ -8,9 +8,9 @@ package dan200.computercraft.shared.computer.apis;
 
 import com.google.common.collect.ImmutableMap;
 import dan200.computercraft.ComputerCraft;
+import dan200.computercraft.api.lua.ILuaAPI;
 import dan200.computercraft.api.lua.ILuaContext;
 import dan200.computercraft.api.lua.LuaException;
-import dan200.computercraft.core.apis.ILuaAPI;
 import dan200.computercraft.shared.computer.blocks.TileCommandComputer;
 import dan200.computercraft.shared.util.WorldUtil;
 import net.minecraft.block.Block;
@@ -49,21 +49,6 @@ public class CommandAPI implements ILuaAPI
         };
     }
 
-    @Override
-    public void startup()
-    {
-    }
-
-    @Override
-    public void advance( double dt )
-    {
-    }
-
-    @Override
-    public void shutdown()
-    {
-    }
-
     @Nonnull
     @Override
     public String[] getMethodNames()

src/main/java/dan200/computercraft/shared/computer/blocks/ComputerProxy.java

@@ -1,9 +1,9 @@
 package dan200.computercraft.shared.computer.blocks;
 
-import dan200.computercraft.shared.computer.core.ServerComputer;
+import dan200.computercraft.shared.computer.core.IComputer;
 
 /**
- * A proxy object for computer objects, delegating to {@link ServerComputer} or {@link TileComputer} where appropriate.
+ * A proxy object for computer objects, delegating to {@link IComputer} or {@link TileComputer} where appropriate.
  */
 public abstract class ComputerProxy
 {
@@ -12,7 +12,7 @@ public abstract class ComputerProxy
     public void turnOn()
     {
         TileComputerBase tile = getTile();
-        ServerComputer computer = tile.getServerComputer();
+        IComputer computer = tile.getComputer();
         if( computer == null )
         {
             tile.m_startOn = true;
@@ -26,7 +26,7 @@ public abstract class ComputerProxy
     public void shutdown()
     {
         TileComputerBase tile = getTile();
-        ServerComputer computer = tile.getServerComputer();
+        IComputer computer = tile.getComputer();
         if( computer == null )
         {
             tile.m_startOn = false;
@@ -40,7 +40,7 @@ public abstract class ComputerProxy
     public void reboot()
     {
         TileComputerBase tile = getTile();
-        ServerComputer computer = tile.getServerComputer();
+        IComputer computer = tile.getComputer();
         if( computer == null )
         {
             tile.m_startOn = true;
@@ -54,7 +54,7 @@ public abstract class ComputerProxy
     public int assignID()
     {
         TileComputerBase tile = getTile();
-        ServerComputer computer = tile.getServerComputer();
+        IComputer computer = tile.getComputer();
         if( computer == null )
         {
             return tile.m_computerID;
@@ -67,14 +67,14 @@ public abstract class ComputerProxy
 
     public boolean isOn()
     {
-        ServerComputer computer = getTile().getServerComputer();
+        IComputer computer = getTile().getComputer();
         return computer != null && computer.isOn();
     }
 
     public String getLabel()
     {
         TileComputerBase tile = getTile();
-        ServerComputer computer = tile.getServerComputer();
+        IComputer computer = tile.getComputer();
         if( computer == null )
         {
             return tile.m_label;

src/main/java/dan200/computercraft/shared/computer/core/ServerComputer.java

@@ -12,7 +12,7 @@ import dan200.computercraft.api.filesystem.IMount;
 import dan200.computercraft.api.filesystem.IWritableMount;
 import dan200.computercraft.api.peripheral.IPeripheral;
 import dan200.computercraft.core.apis.IAPIEnvironment;
-import dan200.computercraft.core.apis.ILuaAPI;
+import dan200.computercraft.api.lua.ILuaAPI;
 import dan200.computercraft.core.computer.Computer;
 import dan200.computercraft.core.computer.IComputerEnvironment;
 import dan200.computercraft.shared.common.ServerTerminal;
@@ -100,8 +100,7 @@ public class ServerComputer extends ServerTerminal
         super.update();
         m_computer.advance( 0.05 );
 
-        m_changedLastFrame = m_changed || m_computer.pollChanged();
-        m_computer.clearChanged();
+        m_changedLastFrame = m_computer.pollAndResetChanged() || m_changed;
         m_changed = false;
 
         m_ticksSincePing++;

src/main/java/dan200/computercraft/shared/peripheral/monitor/TileMonitor.java

@@ -290,7 +290,8 @@ public class TileMonitor extends TilePeripheralBase
 
     public double getTextScale()
     {
-        return m_textScale * 0.5;
+        TileMonitor origin = getOrigin();
+        return (origin == null ? m_textScale : origin.m_textScale) * 0.5;
     }
 
     private void rebuildTerminal()

src/main/java/dan200/computercraft/shared/pocket/apis/PocketAPI.java

@@ -7,10 +7,10 @@
 package dan200.computercraft.shared.pocket.apis;
 
 import dan200.computercraft.ComputerCraft;
+import dan200.computercraft.api.lua.ILuaAPI;
 import dan200.computercraft.api.lua.ILuaContext;
 import dan200.computercraft.api.lua.LuaException;
 import dan200.computercraft.api.pocket.IPocketUpgrade;
-import dan200.computercraft.core.apis.ILuaAPI;
 import dan200.computercraft.shared.pocket.core.PocketServerComputer;
 import dan200.computercraft.shared.util.InventoryUtil;
 import dan200.computercraft.shared.util.WorldUtil;
@@ -39,21 +39,6 @@ public class PocketAPI implements ILuaAPI
         };
     }
 
-    @Override
-    public void startup()
-    {
-    }
-
-    @Override
-    public void advance( double dt )
-    {
-    }
-
-    @Override
-    public void shutdown()
-    {
-    }
-
     @Nonnull
     @Override
     public String[] getMethodNames()

src/main/java/dan200/computercraft/shared/turtle/apis/TurtleAPI.java

@@ -6,13 +6,13 @@
 
 package dan200.computercraft.shared.turtle.apis;
 
+import dan200.computercraft.api.lua.ILuaAPI;
 import dan200.computercraft.api.lua.ILuaContext;
 import dan200.computercraft.api.lua.LuaException;
 import dan200.computercraft.api.turtle.ITurtleAccess;
 import dan200.computercraft.api.turtle.ITurtleCommand;
 import dan200.computercraft.api.turtle.TurtleSide;
 import dan200.computercraft.core.apis.IAPIEnvironment;
-import dan200.computercraft.core.apis.ILuaAPI;
 import dan200.computercraft.shared.turtle.core.*;
 import net.minecraft.item.Item;
 import net.minecraft.item.ItemStack;
@@ -44,21 +44,6 @@ public class TurtleAPI implements ILuaAPI
             "turtle"
         };
     }
-
-    @Override
-    public void startup( )
-    {
-    }
-
-    @Override
-    public void advance( double _dt )
-    {
-    }
-    
-    @Override
-    public void shutdown( )
-    {
-    }
        
     @Nonnull
     @Override

src/main/resources/META-INF/computercraft_at.cfg

@@ -1,3 +1,7 @@
 # RecordMedia (and related methods)
 public net.minecraft.item.ItemRecord field_185076_b # sound
 public net.minecraft.item.ItemRecord field_185077_c # displayName
+# ItemPocketRenderer
+public net.minecraft.client.renderer.ItemRenderer func_187466_c()V # renderArms
+public net.minecraft.client.renderer.ItemRenderer func_178100_c(F)F # getMapAngleFromPitch
+public net.minecraft.client.renderer.ItemRenderer func_187456_a(FFLnet/minecraft/util/EnumHandSide;)V # renderArmFirstPerson