From 574ebf9cf40e2b815395450ea72671c405abc891 Mon Sep 17 00:00:00 2001
From: Nesaak <52047222+Nesaak@users.noreply.github.com>
Date: Wed, 2 Sep 2020 16:06:35 -0400
Subject: [PATCH] Use block index in chunk serialization

---
 .../net/minestom/server/instance/DynamicChunk.java   |  5 ++---
 .../java/net/minestom/server/reader/ChunkReader.java |  8 +++++---
 .../net/minestom/server/utils/chunk/ChunkUtils.java  | 12 ++++++------
 3 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/src/main/java/net/minestom/server/instance/DynamicChunk.java b/src/main/java/net/minestom/server/instance/DynamicChunk.java
index f2f693ea1..94afa86ff 100644
--- a/src/main/java/net/minestom/server/instance/DynamicChunk.java
+++ b/src/main/java/net/minestom/server/instance/DynamicChunk.java
@@ -12,6 +12,7 @@ import net.minestom.server.instance.block.UpdateConsumer;
 import net.minestom.server.network.packet.server.play.ChunkDataPacket;
 import net.minestom.server.utils.MathUtils;
 import net.minestom.server.utils.binary.BinaryWriter;
+import net.minestom.server.utils.chunk.ChunkUtils;
 import net.minestom.server.world.biomes.Biome;
 
 import java.util.concurrent.CopyOnWriteArraySet;
@@ -175,9 +176,7 @@ public class DynamicChunk extends Chunk {
                         continue;
 
                     // Chunk coordinates
-                    binaryWriter.writeByte(x);
-                    binaryWriter.writeShort(y);
-                    binaryWriter.writeByte(z);
+                    binaryWriter.writeShort((short) ChunkUtils.getBlockIndex(x, y, z));
 
                     // Block ids
                     binaryWriter.writeShort(blockStateId);
diff --git a/src/main/java/net/minestom/server/reader/ChunkReader.java b/src/main/java/net/minestom/server/reader/ChunkReader.java
index 095af1335..2857f7f51 100644
--- a/src/main/java/net/minestom/server/reader/ChunkReader.java
+++ b/src/main/java/net/minestom/server/reader/ChunkReader.java
@@ -8,6 +8,7 @@ import net.minestom.server.instance.DynamicChunk;
 import net.minestom.server.instance.Instance;
 import net.minestom.server.instance.batch.ChunkBatch;
 import net.minestom.server.utils.binary.BinaryReader;
+import net.minestom.server.utils.chunk.ChunkUtils;
 import net.minestom.server.world.biomes.Biome;
 import net.minestom.server.world.biomes.BiomeManager;
 
@@ -54,9 +55,10 @@ public class ChunkReader {
 
             while (true) {
                 // Position
-                final byte x = binaryReader.readByte();
-                final short y = binaryReader.readShort();
-                final byte z = binaryReader.readByte();
+                final short index = binaryReader.readShort();
+                final byte x = ChunkUtils.blockIndexToChunkPositionX(index);
+                final short y = ChunkUtils.blockIndexToChunkPositionY(index);
+                final byte z = ChunkUtils.blockIndexToChunkPositionZ(index);
 
                 // Block type
                 final short blockStateId = binaryReader.readShort();
diff --git a/src/main/java/net/minestom/server/utils/chunk/ChunkUtils.java b/src/main/java/net/minestom/server/utils/chunk/ChunkUtils.java
index 5da28381c..f17398d13 100644
--- a/src/main/java/net/minestom/server/utils/chunk/ChunkUtils.java
+++ b/src/main/java/net/minestom/server/utils/chunk/ChunkUtils.java
@@ -237,8 +237,8 @@ public final class ChunkUtils {
      * @param index an index computed from {@link #getBlockIndex(int, int, int)}
      * @return the chunk position X (O-15) of the specified index
      */
-    public static int blockIndexToChunkPositionX(int index) {
-        return blockIndexToPositionX(index, 0);
+    public static byte blockIndexToChunkPositionX(int index) {
+        return (byte) blockIndexToPositionX(index, 0);
     }
 
     /**
@@ -247,8 +247,8 @@ public final class ChunkUtils {
      * @param index an index computed from {@link #getBlockIndex(int, int, int)}
      * @return the chunk position Y (O-255) of the specified index
      */
-    public static int blockIndexToChunkPositionY(int index) {
-        return blockIndexToPositionY(index);
+    public static short blockIndexToChunkPositionY(int index) {
+        return (short) blockIndexToPositionY(index);
     }
 
     /**
@@ -257,8 +257,8 @@ public final class ChunkUtils {
      * @param index an index computed from {@link #getBlockIndex(int, int, int)}
      * @return the chunk position Z (O-15) of the specified index
      */
-    public static int blockIndexToChunkPositionZ(int index) {
-        return blockIndexToPositionZ(index, 0);
+    public static byte blockIndexToChunkPositionZ(int index) {
+        return (byte) blockIndexToPositionZ(index, 0);
     }
 
 }