Implemented snapshot support for 1.2.

src/main/java/org/bukkit/craftbukkit/CraftChunk.java

@@ -1,9 +1,13 @@
 package org.bukkit.craftbukkit;
 
 import java.lang.ref.WeakReference;
-import net.minecraft.server.ChunkPosition;
+import java.util.Arrays;
 
+import net.minecraft.server.BiomeBase;
+import net.minecraft.server.ChunkPosition;
+import net.minecraft.server.ChunkSection;
 import net.minecraft.server.EmptyChunk;
+import net.minecraft.server.WorldChunkManager;
 import net.minecraft.server.WorldServer;
 
 import org.bukkit.Chunk;
@@ -13,20 +17,21 @@ import org.bukkit.block.BlockState;
 import org.bukkit.craftbukkit.block.CraftBlock;
 import org.bukkit.entity.Entity;
 import org.bukkit.ChunkSnapshot;
-import net.minecraft.server.BiomeBase;
-import net.minecraft.server.WorldChunkManager;
-import org.apache.commons.lang.NotImplementedException;
 
 public class CraftChunk implements Chunk {
     private WeakReference<net.minecraft.server.Chunk> weakChunk;
     private WorldServer worldServer;
     private int x;
     private int z;
+    private static final byte[] emptyData = new byte[2048];
+    private static final short[] emptyBlockIDs = new short[4096];
+    private static final byte[] emptySkyLight = new byte[2048];
 
     public CraftChunk(net.minecraft.server.Chunk chunk) {
         if (!(chunk instanceof EmptyChunk)) {
             this.weakChunk = new WeakReference<net.minecraft.server.Chunk>(chunk);
         }
+
         worldServer = (WorldServer) getHandle().world;
         x = getHandle().x;
         z = getHandle().z;
@@ -42,12 +47,15 @@ public class CraftChunk implements Chunk {
 
     public net.minecraft.server.Chunk getHandle() {
         net.minecraft.server.Chunk c = weakChunk.get();
+
         if (c == null) {
             c = worldServer.getChunkAt(x, z);
+
             if (!(c instanceof EmptyChunk)) {
                 weakChunk = new WeakReference<net.minecraft.server.Chunk>(c);
             }
         }
+
         return c;
     }
 
@@ -75,19 +83,23 @@ public class CraftChunk implements Chunk {
     public Entity[] getEntities() {
         int count = 0, index = 0;
         net.minecraft.server.Chunk chunk = getHandle();
+
         for (int i = 0; i < 8; i++) {
             count += chunk.entitySlices[i].size();
         }
 
         Entity[] entities = new Entity[count];
+
         for (int i = 0; i < 8; i++) {
             for (Object obj : chunk.entitySlices[i].toArray()) {
                 if (!(obj instanceof net.minecraft.server.Entity)) {
                     continue;
                 }
+
                 entities[index++] = ((net.minecraft.server.Entity) obj).getBukkitEntity();
             }
         }
+
         return entities;
     }
 
@@ -95,10 +107,12 @@ public class CraftChunk implements Chunk {
         int index = 0;
         net.minecraft.server.Chunk chunk = getHandle();
         BlockState[] entities = new BlockState[chunk.tileEntities.size()];
+
         for (Object obj : chunk.tileEntities.keySet().toArray()) {
             if (!(obj instanceof ChunkPosition)) {
                 continue;
             }
+
             ChunkPosition position = (ChunkPosition) obj;
             entities[index++] = worldServer.getWorld().getBlockAt(position.x + (chunk.x << 4), position.y, position.z + (chunk.z << 4)).getState();
         }
@@ -133,16 +147,63 @@ public class CraftChunk implements Chunk {
         return getChunkSnapshot(true, false, false);
     }
 
-    public ChunkSnapshot getChunkSnapshot(boolean includeMaxblocky, boolean includeBiome, boolean includeBiomeTempRain) {
+    public ChunkSnapshot getChunkSnapshot(boolean includeMaxBlockY, boolean includeBiome, boolean includeBiomeTempRain) {
         net.minecraft.server.Chunk chunk = getHandle();
-        byte[] buf = new byte[32768 + 16384 + 16384 + 16384]; // Get big enough buffer for whole chunk
-        //chunk.getData(buf, 0, 0, 0, 16, 128, 16, 0); // Get whole chunk
-        byte[] hmap = null;
 
-        if (true) throw new NotImplementedException("Chunk snapshots do not yet work"); // TODO: Snapshots.
+        ChunkSection[] cs = chunk.h(); /* Get sections */
+        short[][] sectionBlockIDs = new short[cs.length][];
+        byte[][] sectionBlockData = new byte[cs.length][];
+        byte[][] sectionSkyLights = new byte[cs.length][];
+        byte[][] sectionEmitLights = new byte[cs.length][];
+        boolean[] sectionEmpty = new boolean[cs.length];
 
-        if (includeMaxblocky) {
+        for (int i = 0; i < cs.length; i++) {
-            hmap = new byte[256]; // Get copy of height map
+            if (cs[i] == null) { /* Section is empty? */
+                sectionBlockIDs[i] = emptyBlockIDs;
+                sectionBlockData[i] = emptyData;
+                sectionSkyLights[i] = emptySkyLight;
+                sectionEmitLights[i] = emptyData;
+                sectionEmpty[i] = true;
+            } else { /* Not empty */
+                short[] blockids = new short[4096];
+                byte[] baseids = cs[i].g();
+
+                /* Copy base IDs */
+                for (int j = 0; j < 4096; j++) {
+                    blockids[j] = (short) (baseids[j] & 0xFF);
+                }
+
+                if (cs[i].h() != null) { /* If we've got extended IDs */
+                    byte[] extids = cs[i].h().a;
+
+                    for (int j = 0; j < 2048; j++) {
+                        short b = (short) (extids[j] & 0xFF);
+
+                        if (b == 0) {
+                            continue;
+                        }
+
+                        blockids[j<<1] |= (b & 0xF0) << 4;
+                        blockids[(j<<1)+1] |= (b & 0x0F) << 8;
+                    }
+                }
+
+                sectionBlockIDs[i] = blockids;
+
+                /* Get block data nibbles */
+                sectionBlockData[i] = new byte[2048];
+                System.arraycopy(cs[i].i().a, 0, sectionBlockData[i], 0, 2048);
+                sectionSkyLights[i] = new byte[2048];
+                System.arraycopy(cs[i].k().a, 0, sectionSkyLights[i], 0, 2048);
+                sectionEmitLights[i] = new byte[2048];
+                System.arraycopy(cs[i].j().a, 0, sectionEmitLights[i], 0, 2048);
+            }
+        }
+
+        int[] hmap = null;
+
+        if (includeMaxBlockY) {
+            hmap = new int[256]; // Get copy of height map
             System.arraycopy(chunk.heightMap, 0, hmap, 0, 256);
         }
 
@@ -162,44 +223,21 @@ public class CraftChunk implements Chunk {
                 biomeTemp = new double[256];
                 biomeRain = new double[256];
                 float[] dat = wcm.getTemperatures((float[]) null, getX() << 4, getZ() << 4, 16, 16);
-                for (int i = 0; i < 256; i++)
+
+                for (int i = 0; i < 256; i++) {
                     biomeTemp[i] = dat[i];
+                }
+
                 dat = wcm.getWetness((float[]) null, getX() << 4, getZ() << 4, 16, 16);
-                for (int i = 0; i < 256; i++)
+
+                for (int i = 0; i < 256; i++) {
                     biomeRain[i] = dat[i];
                 }
             }
+        }
+
         World world = getWorld();
-        return new CraftChunkSnapshot(getX(), getZ(), world.getName(), world.getFullTime(), buf, hmap, biome, biomeTemp, biomeRain);
+        return new CraftChunkSnapshot(getX(), getZ(), world.getName(), world.getFullTime(), sectionBlockIDs, sectionBlockData, sectionSkyLights, sectionEmitLights, sectionEmpty, hmap, biome, biomeTemp, biomeRain);
-    }
-
-    /**
-     * Empty chunk snapshot - nothing but air blocks, but can include valid biome data
-     */
-    private static class EmptyChunkSnapshot extends CraftChunkSnapshot {
-        EmptyChunkSnapshot(int x, int z, String worldName, long time, BiomeBase[] biome, double[] biomeTemp, double[] biomeRain) {
-            super(x, z, worldName, time, null, null, biome, biomeTemp, biomeRain);
-        }
-
-        public final int getBlockTypeId(int x, int y, int z) {
-            return 0;
-        }
-
-        public final int getBlockData(int x, int y, int z) {
-            return 0;
-        }
-
-        public final int getBlockSkyLight(int x, int y, int z) {
-            return 15;
-        }
-
-        public final int getBlockEmittedLight(int x, int y, int z) {
-            return 0;
-        }
-
-        public final int getHighestBlockYAt(int x, int z) {
-            return 0;
-        }
     }
 
     public static ChunkSnapshot getEmptyChunkSnapshot(int x, int z, CraftWorld world, boolean includeBiome, boolean includeBiomeTempRain) {
@@ -219,13 +257,39 @@ public class CraftChunk implements Chunk {
                 biomeTemp = new double[256];
                 biomeRain = new double[256];
                 float[] dat = wcm.getTemperatures((float[]) null, x << 4, z << 4, 16, 16);
-                for (int i = 0; i < 256; i++)
+
+                for (int i = 0; i < 256; i++) {
                     biomeTemp[i] = dat[i];
+                }
+
                 dat = wcm.getWetness((float[]) null, x << 4, z << 4, 16, 16);
-                for (int i = 0; i < 256; i++)
+
+                for (int i = 0; i < 256; i++) {
                     biomeRain[i] = dat[i];
                 }
             }
-        return new EmptyChunkSnapshot(x, z, world.getName(), world.getFullTime(), biome, biomeTemp, biomeRain);
+        }
+
+        /* Fill with empty data */
+        int hSection = world.getMaxHeight() >> 4;
+        short[][] blockIDs = new short[hSection][];
+        byte[][] skyLight = new byte[hSection][];
+        byte[][] emitLight = new byte[hSection][];
+        byte[][] blockData = new byte[hSection][];
+        boolean[] empty = new boolean[hSection];
+
+        for (int i = 0; i < hSection; i++) {
+            blockIDs[i] = emptyBlockIDs;
+            skyLight[i] = emptySkyLight;
+            emitLight[i] = emptyData;
+            blockData[i] = emptyData;
+            empty[i] = true;
+        }
+
+        return new CraftChunkSnapshot(x, z, world.getName(), world.getFullTime(), blockIDs, blockData, skyLight, emitLight, empty, new int[256], biome, biomeTemp, biomeRain);
+    }
+
+    static {
+        Arrays.fill(emptySkyLight, (byte) 0xFF);
     }
 }

src/main/java/org/bukkit/craftbukkit/CraftChunkSnapshot.java

@@ -13,23 +13,27 @@ import net.minecraft.server.BiomeBase;
 public class CraftChunkSnapshot implements ChunkSnapshot {
     private final int x, z;
     private final String worldname;
-    private final byte[] buf; // Flat buffer in uncompressed chunk file format
+    private final short[][] blockids; /* Block IDs, by section */
-    private final byte[] hmap; // Height map
+    private final byte[][] blockdata;
+    private final byte[][] skylight;
+    private final byte[][] emitlight;
+    private final boolean[] empty;
+    private final int[] hmap; // Height map
     private final long captureFulltime;
     private final BiomeBase[] biome;
     private final double[] biomeTemp;
     private final double[] biomeRain;
 
-    private static final int BLOCKDATA_OFF = 32768;
+    CraftChunkSnapshot(int x, int z, String wname, long wtime, short[][] sectionBlockIDs, byte[][] sectionBlockData, byte[][] sectionSkyLights, byte[][] sectionEmitLights, boolean[] sectionEmpty, int[] hmap, BiomeBase[] biome, double[] biomeTemp, double[] biomeRain) {
-    private static final int BLOCKLIGHT_OFF = BLOCKDATA_OFF + 16384;
-    private static final int SKYLIGHT_OFF = BLOCKLIGHT_OFF + 16384;
-
-    CraftChunkSnapshot(int x, int z, String wname, long wtime, byte[] buf, byte[] hmap, BiomeBase[] biome, double[] biomeTemp, double[] biomeRain) {
         this.x = x;
         this.z = z;
         this.worldname = wname;
         this.captureFulltime = wtime;
-        this.buf = buf;
+        this.blockids = sectionBlockIDs;
+        this.blockdata = sectionBlockData;
+        this.skylight = sectionSkyLights;
+        this.emitlight = sectionEmitLights;
+        this.empty = sectionEmpty;
         this.hmap = hmap;
         this.biome = biome;
         this.biomeTemp = biomeTemp;
@@ -48,45 +52,46 @@ public class CraftChunkSnapshot implements ChunkSnapshot {
         return worldname;
     }
 
-    public int getBlockTypeId(int x, int y, int z) {
+    public final int getBlockTypeId(int x, int y, int z) {
-        return buf[x << 11 | z << 7 | y] & 255;
+        return blockids[y >> 4][((y & 0xF) << 8) | (z << 4) | x];
     }
 
-    public int getBlockData(int x, int y, int z) {
+    public final int getBlockData(int x, int y, int z) {
-        int off = ((x << 10) | (z << 6) | (y >> 1)) + BLOCKDATA_OFF;
+        int off = ((y & 0xF) << 7) | (z << 3) | (x >> 1);
-
+        return (blockdata[y >> 4][off] >> ((x & 1) << 2)) & 0xF;
-        return ((y & 1) == 0) ? (buf[off] & 0xF) : ((buf[off] >> 4) & 0xF);
     }
 
-    public int getBlockSkyLight(int x, int y, int z) {
+    public final int getBlockSkyLight(int x, int y, int z) {
-        int off = ((x << 10) | (z << 6) | (y >> 1)) + SKYLIGHT_OFF;
+        int off = ((y & 0xF) << 7) | (z << 3) | (x >> 1);
-
+        return (skylight[y >> 4][off] >> ((x & 1) << 2)) & 0xF;
-        return ((y & 1) == 0) ? (buf[off] & 0xF) : ((buf[off] >> 4) & 0xF);
     }
 
-    public int getBlockEmittedLight(int x, int y, int z) {
+    public final int getBlockEmittedLight(int x, int y, int z) {
-        int off = ((x << 10) | (z << 6) | (y >> 1)) + BLOCKLIGHT_OFF;
+        int off = ((y & 0xF) << 7) | (z << 3) | (x >> 1);
-
+        return (emitlight[y >> 4][off] >> ((x & 1) << 2)) & 0xF;
-        return ((y & 1) == 0) ? (buf[off] & 0xF) : ((buf[off] >> 4) & 0xF);
     }
 
-    public int getHighestBlockYAt(int x, int z) {
+    public final int getHighestBlockYAt(int x, int z) {
-        return hmap[z << 4 | x] & 255;
+        return hmap[z << 4 | x];
     }
 
-    public Biome getBiome(int x, int z) {
+    public final Biome getBiome(int x, int z) {
         return CraftBlock.biomeBaseToBiome(biome[z << 4 | x]);
     }
 
-    public double getRawBiomeTemperature(int x, int z) {
+    public final double getRawBiomeTemperature(int x, int z) {
         return biomeTemp[z << 4 | x];
     }
 
-    public double getRawBiomeRainfall(int x, int z) {
+    public final double getRawBiomeRainfall(int x, int z) {
         return biomeRain[z << 4 | x];
     }
 
-    public long getCaptureFullTime() {
+    public final long getCaptureFullTime() {
         return captureFulltime;
     }
+
+    public final boolean isSectionEmpty(int sy) {
+        return empty[sy];
+    }
 }