Support persistent chunk sections for client caching

Author: valaphee

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

@@ -26,13 +26,18 @@
 package org.geysermc.geyser.level.chunk;
 
 import io.netty.buffer.ByteBuf;
+import io.netty.buffer.ByteBufOutputStream;
 import it.unimi.dsi.fastutil.ints.IntArrayList;
 import it.unimi.dsi.fastutil.ints.IntList;
 import lombok.Getter;
+import org.cloudburstmc.nbt.NBTOutputStream;
+import org.cloudburstmc.nbt.NbtUtils;
 import org.cloudburstmc.protocol.common.util.VarInts;
 import org.geysermc.geyser.level.chunk.bitarray.BitArray;
 import org.geysermc.geyser.level.chunk.bitarray.BitArrayVersion;
+import org.geysermc.geyser.registry.type.BlockMappings;
 
+import java.io.IOException;
 import java.util.function.IntConsumer;
 
 @Getter
@@ -82,6 +87,20 @@ public void writeToNetwork(ByteBuf buffer) {
         palette.forEach((IntConsumer) id -> VarInts.writeInt(buffer, id));
     }
 
+    public void writeToNetwork(ByteBuf buffer, BlockMappings blockMappings) throws IOException {
+        buffer.writeByte(getPaletteHeader(bitArray.getVersion(), false));
+
+        for (int word : bitArray.getWords()) {
+            buffer.writeIntLE(word);
+        }
+
+        bitArray.writeSizeToNetwork(buffer, palette.size());
+        NBTOutputStream nbtStream = NbtUtils.createNetworkWriter(new ByteBufOutputStream(buffer));
+        for (int id : palette) {
+            nbtStream.writeTag(blockMappings.getDefinition(id));
+        }
+    }
+
     public int estimateNetworkSize() {
         int size = 1; // Palette header
         size += this.bitArray.getWords().length * 4;
@@ -134,4 +153,4 @@ public boolean isEmpty() {
     public BlockStorage copy() {
         return new BlockStorage(this.bitArray.copy(), new IntArrayList(this.palette));
     }
-}
+}

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

@@ -27,6 +27,9 @@
 
 import io.netty.buffer.ByteBuf;
 import org.cloudburstmc.protocol.common.util.Preconditions;
+import org.geysermc.geyser.registry.type.BlockMappings;
+
+import java.io.IOException;
 
 public class GeyserChunkSection {
 
@@ -68,6 +71,16 @@ public void writeToNetwork(ByteBuf buffer) {
         }
     }
 
+    public void writeToNetwork(ByteBuf buffer, BlockMappings blockMappings) throws IOException {
+        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, blockMappings);
+        }
+    }
+
     public int estimateNetworkSize() {
         int size = 2; // Version + storage count
         for (BlockStorage blockStorage : this.storage) {

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

@@ -41,7 +41,6 @@
 import org.geysermc.geyser.level.block.Blocks;
 import org.geysermc.geyser.level.block.type.BlockState;
 import org.geysermc.geyser.level.chunk.BlockStorage;
-import org.geysermc.geyser.level.chunk.GeyserChunkSection;
 import org.geysermc.geyser.level.chunk.bitarray.SingletonBitArray;
 import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.session.cache.registry.JavaRegistries;
@@ -56,28 +55,12 @@ public class ChunkUtils {
 
     public static final byte[] EMPTY_BIOME_DATA;
     public static final BlockStorage[] EMPTY_BLOCK_STORAGE;
-    public static final int EMPTY_CHUNK_SECTION_SIZE;
     private static final ConcurrentHashMap<Integer, byte[]> EMPTY_CHUNK_PAYLOAD_CACHE = new ConcurrentHashMap<>(3);
 
     static {
         EMPTY_BLOCK_STORAGE = new BlockStorage[0];
 
         ByteBuf byteBuf = Unpooled.buffer();
-        try {
-            new GeyserChunkSection(EMPTY_BLOCK_STORAGE, 0)
-                    .writeToNetwork(byteBuf);
-
-            byte[] emptyChunkData = new byte[byteBuf.readableBytes()];
-            byteBuf.readBytes(emptyChunkData);
-
-            EMPTY_CHUNK_SECTION_SIZE = emptyChunkData.length;
-
-            emptyChunkData = null;
-        } finally {
-            byteBuf.release();
-        }
-
-        byteBuf = Unpooled.buffer();
         try {
             BlockStorage blockStorage = new BlockStorage(SingletonBitArray.INSTANCE, IntLists.singleton(0));
             blockStorage.writeToNetwork(byteBuf);