Re-implement subchunk v9 with proper index (#4287)

* Re-implement subchunk v9 with proper index

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

* typo in comment

---------

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

build.gradle.kts

@@ -1,5 +1,7 @@
 plugins {
     `java-library`
+    // Ensure AP works in eclipse (no effect on other IDEs)
+    `eclipse`
     id("geyser.build-logic")
     id("io.freefair.lombok") version "6.3.0" apply false
 }
@@ -35,4 +37,4 @@ subprojects {
         in platforms -> plugins.apply("geyser.platform-conventions")
         else -> plugins.apply("geyser.base-conventions")
     }
-}
+}

core/src/main/java/org/geysermc/geyser/level/chunk/GeyserChunkSection.java

@@ -30,18 +30,20 @@ import org.cloudburstmc.protocol.common.util.Preconditions;
 
 public class GeyserChunkSection {
 
-    // Temporary reversion to v8 as it reduces the frequnecy of https://github.com/GeyserMC/Geyser/issues/4240
+    // As of at least 1.19.80
-    // This does not fully resolve the issue so a better solution is still needed
+    private static final int CHUNK_SECTION_VERSION = 9;
-    private static final int CHUNK_SECTION_VERSION = 8;
 
     private final BlockStorage[] storage;
+    // Counts up from 00 for y >= 0 and down from FF for y < 0
+    private final int subChunkIndex;
 
-    public GeyserChunkSection(int airBlockId) {
+    public GeyserChunkSection(int airBlockId, int subChunkIndex) {
-        this(new BlockStorage[]{new BlockStorage(airBlockId), new BlockStorage(airBlockId)});
+        this(new BlockStorage[]{new BlockStorage(airBlockId), new BlockStorage(airBlockId)}, subChunkIndex);
     }
 
-    public GeyserChunkSection(BlockStorage[] storage) {
+    public GeyserChunkSection(BlockStorage[] storage, int subChunkIndex) {
         this.storage = storage;
+        this.subChunkIndex = subChunkIndex;
     }
 
     public int getFullBlock(int x, int y, int z, int layer) {
@@ -60,6 +62,7 @@ public class GeyserChunkSection {
         buffer.writeByte(CHUNK_SECTION_VERSION);
         buffer.writeByte(this.storage.length);
         // Required for chunk version 9+
+        buffer.writeByte(this.subChunkIndex);
         for (BlockStorage blockStorage : this.storage) {
             blockStorage.writeToNetwork(buffer);
         }
@@ -86,12 +89,12 @@ public class GeyserChunkSection {
         return true;
     }
 
-    public GeyserChunkSection copy() {
+    public GeyserChunkSection copy(int subChunkIndex) {
         BlockStorage[] storage = new BlockStorage[this.storage.length];
         for (int i = 0; i < storage.length; i++) {
             storage[i] = this.storage[i].copy();
         }
-        return new GeyserChunkSection(storage);
+        return new GeyserChunkSection(storage, subChunkIndex);
     }
 
     public static int blockPosition(int x, int y, int z) {

core/src/main/java/org/geysermc/geyser/translator/protocol/java/level/JavaLevelChunkWithLightTranslator.java

@@ -78,7 +78,8 @@ import java.util.BitSet;
 import java.util.List;
 import java.util.Map;
 
-import static org.geysermc.geyser.util.ChunkUtils.SERIALIZED_CHUNK_DATA;
+import static org.geysermc.geyser.util.ChunkUtils.EMPTY_BLOCK_STORAGE;
+import static org.geysermc.geyser.util.ChunkUtils.EMPTY_CHUNK_SECTION_SIZE;
 import static org.geysermc.geyser.util.ChunkUtils.indexYZXtoXZY;
 
 @Translator(packet = ClientboundLevelChunkWithLightPacket.class)
@@ -127,6 +128,7 @@ public class JavaLevelChunkWithLightTranslator extends PacketTranslator<Clientbo
                 boolean thisExtendedCollisionNextSection = false;
 
                 int bedrockSectionY = sectionY + (yOffset - (bedrockDimension.minY() >> 4));
+                int subChunkIndex = sectionY + yOffset;
                 if (bedrockSectionY < 0 || maxBedrockSectionY < bedrockSectionY) {
                     // Ignore this chunk section since it goes outside the bounds accepted by the Bedrock client
                     if (useExtendedCollisions) {
@@ -154,7 +156,7 @@ public class JavaLevelChunkWithLightTranslator extends PacketTranslator<Clientbo
                             }
     
                             BlockStorage[] layers = new BlockStorage[]{ layer0 };
-                            sections[bedrockSectionY] = new GeyserChunkSection(layers);
+                            sections[bedrockSectionY] = new GeyserChunkSection(layers, subChunkIndex);
                         }
                         EXTENDED_COLLISIONS_STORAGE.get().clear();
                         extendedCollisionNextSection = false;
@@ -167,7 +169,7 @@ public class JavaLevelChunkWithLightTranslator extends PacketTranslator<Clientbo
 
                 if (javaPalette instanceof GlobalPalette) {
                     // As this is the global palette, simply iterate through the whole chunk section once
-                    GeyserChunkSection section = new GeyserChunkSection(session.getBlockMappings().getBedrockAir().getRuntimeId());
+                    GeyserChunkSection section = new GeyserChunkSection(session.getBlockMappings().getBedrockAir().getRuntimeId(), subChunkIndex);
                     for (int yzx = 0; yzx < BlockStorage.SIZE; yzx++) {
                         int javaId = javaData.get(yzx);
                         int bedrockId = session.getBlockMappings().getBedrockBlockId(javaId);
@@ -217,9 +219,9 @@ public class JavaLevelChunkWithLightTranslator extends PacketTranslator<Clientbo
 
                     if (BlockRegistries.WATERLOGGED.get().get(javaId)) {
                         BlockStorage waterlogged = new BlockStorage(SingletonBitArray.INSTANCE, IntLists.singleton(session.getBlockMappings().getBedrockWater().getRuntimeId()));
-                        sections[bedrockSectionY] = new GeyserChunkSection(new BlockStorage[] {blockStorage, waterlogged});
+                        sections[bedrockSectionY] = new GeyserChunkSection(new BlockStorage[] {blockStorage, waterlogged}, subChunkIndex);
                     } else {
-                        sections[bedrockSectionY] = new GeyserChunkSection(new BlockStorage[] {blockStorage});
+                        sections[bedrockSectionY] = new GeyserChunkSection(new BlockStorage[] {blockStorage}, subChunkIndex);
                     }
                     if (useExtendedCollisions) {
                         EXTENDED_COLLISIONS_STORAGE.get().clear();
@@ -378,7 +380,7 @@ public class JavaLevelChunkWithLightTranslator extends PacketTranslator<Clientbo
                     layers = new BlockStorage[]{ layer0, new BlockStorage(BitArrayVersion.V1.createArray(BlockStorage.SIZE, layer1Data), layer1Palette) };
                 }
 
-                sections[bedrockSectionY] = new GeyserChunkSection(layers);
+                sections[bedrockSectionY] = new GeyserChunkSection(layers, subChunkIndex);
                 extendedCollisionNextSection = thisExtendedCollisionNextSection;
             }
 
@@ -426,13 +428,14 @@ public class JavaLevelChunkWithLightTranslator extends PacketTranslator<Clientbo
                     BlockDefinition blockDefinition = SkullBlockEntityTranslator.translateSkull(session, tag, Vector3i.from(x + chunkBlockX, y, z + chunkBlockZ), blockState);
                     if (blockDefinition != null) {
                         int bedrockSectionY = (y >> 4) - (bedrockDimension.minY() >> 4);
+                        int subChunkIndex = (y >> 4) + (bedrockDimension.minY() >> 4);
                         if (0 <= bedrockSectionY && bedrockSectionY < maxBedrockSectionY) {
                             // Custom skull is in a section accepted by Bedrock
                             GeyserChunkSection bedrockSection = sections[bedrockSectionY];
                             IntList palette = bedrockSection.getBlockStorageArray()[0].getPalette();
                             if (palette instanceof IntImmutableList || palette instanceof IntLists.Singleton) {
                                 // TODO there has to be a better way to expand the palette .-.
-                                bedrockSection = bedrockSection.copy();
+                                bedrockSection = bedrockSection.copy(subChunkIndex);
                                 sections[bedrockSectionY] = bedrockSection;
                             }
                             bedrockSection.setFullBlock(x, y & 0xF, z, 0, blockDefinition.getRuntimeId());
@@ -458,7 +461,7 @@ public class JavaLevelChunkWithLightTranslator extends PacketTranslator<Clientbo
                 if (section != null) {
                     size += section.estimateNetworkSize();
                 } else {
-                    size += SERIALIZED_CHUNK_DATA.length;
+                    size += EMPTY_CHUNK_SECTION_SIZE;
                 }
             }
             size += ChunkUtils.EMPTY_BIOME_DATA.length * biomeCount;
@@ -472,7 +475,8 @@ public class JavaLevelChunkWithLightTranslator extends PacketTranslator<Clientbo
                 if (section != null) {
                     section.writeToNetwork(byteBuf);
                 } else {
-                    byteBuf.writeBytes(SERIALIZED_CHUNK_DATA);
+                    int subChunkIndex = (i + (bedrockDimension.minY() >> 4));
+                    new GeyserChunkSection(EMPTY_BLOCK_STORAGE, subChunkIndex).writeToNetwork(byteBuf);
                 }
             }
 

core/src/main/java/org/geysermc/geyser/util/ChunkUtils.java

@@ -54,19 +54,27 @@ import static org.geysermc.geyser.level.block.BlockStateValues.JAVA_AIR_ID;
 
 @UtilityClass
 public class ChunkUtils {
-    /**
+
-     * An empty subchunk.
-     */
-    public static final byte[] SERIALIZED_CHUNK_DATA;
     public static final byte[] EMPTY_BIOME_DATA;
 
+    public static final BlockStorage[] EMPTY_BLOCK_STORAGE;
+
+    public static final int EMPTY_CHUNK_SECTION_SIZE;
+
     static {
+        EMPTY_BLOCK_STORAGE = new BlockStorage[0];
+
         ByteBuf byteBuf = Unpooled.buffer();
         try {
-            new GeyserChunkSection(new BlockStorage[0])
+            new GeyserChunkSection(EMPTY_BLOCK_STORAGE, 0)
                     .writeToNetwork(byteBuf);
-            SERIALIZED_CHUNK_DATA = new byte[byteBuf.readableBytes()];
+
-            byteBuf.readBytes(SERIALIZED_CHUNK_DATA);
+            byte[] emptyChunkData = new byte[byteBuf.readableBytes()];
+            byteBuf.readBytes(emptyChunkData);
+
+            EMPTY_CHUNK_SECTION_SIZE = emptyChunkData.length;
+
+            emptyChunkData = null;
         } finally {
             byteBuf.release();
         }