send individual section updates when less than half of the sections are updated.

src/main/java/net/minestom/server/instance/Chunk.java

@@ -8,7 +8,6 @@ import net.minestom.server.entity.Player;
 import net.minestom.server.entity.pathfinding.PFColumnarSpace;
 import net.minestom.server.event.player.PlayerChunkLoadEvent;
 import net.minestom.server.event.player.PlayerChunkUnloadEvent;
-import net.minestom.server.instance.batch.BatchOption;
 import net.minestom.server.instance.block.Block;
 import net.minestom.server.instance.block.BlockManager;
 import net.minestom.server.instance.block.CustomBlock;
@@ -31,7 +30,6 @@ import org.jetbrains.annotations.Nullable;
 
 import java.util.*;
 import java.util.concurrent.CopyOnWriteArraySet;
-import java.util.stream.Collectors;
 
 // TODO light data & API
 
@@ -547,23 +545,6 @@ public abstract class Chunk implements Viewable, DataContainer {
         PacketUtils.sendGroupedPacket(getViewers(), getFreshFullDataPacket());
     }
 
-    /**
-     * Sends a single section {@link ChunkDataPacket} to all chunk viewers.
-     *
-     * @param section The section to send.
-     */
-    public synchronized void sendChunkSectionUpdate(int section) {
-        Check.argCondition(!MathUtils.isBetween(section, 0, CHUNK_SECTION_COUNT),
-                "The chunk section " + section + " does not exist");
-        PacketUtils.sendGroupedPacket(
-                //todo An option to filter out non-netty clients in sendGroupedPacket would be nice.
-                getViewers()
-                        .stream()
-                        .filter(PlayerUtils::isNettyClient)
-                        .collect(Collectors.toUnmodifiableList()),
-                createChunkSectionUpdatePacket(section));
-    }
-
     /**
      * Sends a chunk section update packet to {@code player}.
      *
@@ -589,7 +570,6 @@ public abstract class Chunk implements Viewable, DataContainer {
     @NotNull
     protected ChunkDataPacket createChunkSectionUpdatePacket(int section) {
         ChunkDataPacket chunkDataPacket = getFreshPartialDataPacket();
-        chunkDataPacket.fullChunk = false;
         int[] sections = new int[CHUNK_SECTION_COUNT];
         sections[section] = 1;
         chunkDataPacket.sections = sections;

src/main/java/net/minestom/server/instance/batch/ChunkBatch.java

@@ -10,10 +10,13 @@ import net.minestom.server.data.Data;
 import net.minestom.server.instance.Chunk;
 import net.minestom.server.instance.Instance;
 import net.minestom.server.instance.InstanceContainer;
+import net.minestom.server.network.packet.server.play.ChunkDataPacket;
+import net.minestom.server.utils.PacketUtils;
 import net.minestom.server.utils.block.CustomBlockUtils;
 import net.minestom.server.utils.callback.OptionalCallback;
 import net.minestom.server.utils.chunk.ChunkCallback;
 import net.minestom.server.utils.chunk.ChunkUtils;
+import net.minestom.server.utils.player.PlayerUtils;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.slf4j.Logger;
@@ -35,7 +38,6 @@ import java.util.function.IntConsumer;
  * @see Batch
  */
 public class ChunkBatch implements Batch<ChunkCallback> {
-    private static final int CHUNK_SECTION_THRESHOLD = Chunk.CHUNK_SECTION_COUNT / 2;
     private static final Logger LOGGER = LoggerFactory.getLogger(ChunkBatch.class);
 
 
@@ -252,15 +254,14 @@ public class ChunkBatch implements Batch<ChunkCallback> {
     /**
      * Updates the given chunk for all of its viewers, and executes the callback.
      */
-    private void updateChunk(@NotNull Instance instance, Chunk chunk, IntSet sections, @Nullable ChunkCallback callback, boolean safeCallback) {
+    private void updateChunk(@NotNull Instance instance, Chunk chunk, IntSet updatedSections, @Nullable ChunkCallback callback, boolean safeCallback) {
         // Refresh chunk for viewers
-        if (sections.size() <= CHUNK_SECTION_THRESHOLD) {
+        ChunkDataPacket chunkDataPacket = chunk.getFreshPartialDataPacket();
-            // Update only a few sections of the chunk
+        int[] sections = new int[Chunk.CHUNK_SECTION_COUNT];
-            sections.forEach((IntConsumer) chunk::sendChunkSectionUpdate);
+        for (int section : updatedSections)
-        } else {
+            sections[section] = 1;
-            // Update the entire chunk
+        chunkDataPacket.sections = sections;
-            chunk.sendChunk();
+        PacketUtils.sendGroupedPacket(chunk.getViewers(), chunkDataPacket, PlayerUtils::isNettyClient);
-        }
 
         if (instance instanceof InstanceContainer) {
             // FIXME: put method in Instance instead