From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Wed, 6 May 2020 05:00:57 -0400
Subject: [PATCH] Handle Oversized block entities in chunks

Splits out Extra Packets if too many TE's are encountered to prevent
creating too large of a packet to sed.

Co-authored-by: Spottedleaf <Spottedleaf@users.noreply.github.com>

diff --git a/net/minecraft/network/protocol/game/ClientboundLevelChunkPacketData.java b/net/minecraft/network/protocol/game/ClientboundLevelChunkPacketData.java
index 5d1943d37dfad0c12e77179f0866851532d983e9..0a7e6c639d5125a135a43476bbb2ef2d682f743c 100644
--- a/net/minecraft/network/protocol/game/ClientboundLevelChunkPacketData.java
+++ b/net/minecraft/network/protocol/game/ClientboundLevelChunkPacketData.java
@@ -27,6 +27,14 @@ public class ClientboundLevelChunkPacketData {
     private final CompoundTag heightmaps;
     private final byte[] buffer;
     private final List<ClientboundLevelChunkPacketData.BlockEntityInfo> blockEntitiesData;
+    // Paper start - Handle oversized block entities in chunks
+    private final java.util.List<net.minecraft.network.protocol.Packet<?>> extraPackets = new java.util.ArrayList<>();
+    private static final int BLOCK_ENTITY_LIMIT = Integer.getInteger("Paper.excessiveTELimit", 750);
+
+    public List<net.minecraft.network.protocol.Packet<?>> getExtraPackets() {
+        return this.extraPackets;
+    }
+    // Paper end - Handle oversized block entities in chunks
 
     public ClientboundLevelChunkPacketData(LevelChunk levelChunk) {
         this.heightmaps = new CompoundTag();
@@ -40,8 +48,18 @@ public class ClientboundLevelChunkPacketData {
         this.buffer = new byte[calculateChunkSize(levelChunk)];
         extractChunkData(new FriendlyByteBuf(this.getWriteBuffer()), levelChunk);
         this.blockEntitiesData = Lists.newArrayList();
+        int totalTileEntities = 0; // Paper - Handle oversized block entities in chunks
 
         for (Entry<BlockPos, BlockEntity> entryx : levelChunk.getBlockEntities().entrySet()) {
+            // Paper start - Handle oversized block entities in chunks
+            if (++totalTileEntities > BLOCK_ENTITY_LIMIT) {
+                net.minecraft.network.protocol.Packet<ClientGamePacketListener> packet = entryx.getValue().getUpdatePacket();
+                if (packet != null) {
+                    this.extraPackets.add(packet);
+                    continue;
+                }
+            }
+            // Paper end - Handle oversized block entities in chunks
             this.blockEntitiesData.add(ClientboundLevelChunkPacketData.BlockEntityInfo.create(entryx.getValue()));
         }
     }
diff --git a/net/minecraft/network/protocol/game/ClientboundLevelChunkWithLightPacket.java b/net/minecraft/network/protocol/game/ClientboundLevelChunkWithLightPacket.java
index aadf2dccb996e422cacf8bb510cc642e69ee4972..5288de783481b7e932017c679b9eaa715b8826c6 100644
--- a/net/minecraft/network/protocol/game/ClientboundLevelChunkWithLightPacket.java
+++ b/net/minecraft/network/protocol/game/ClientboundLevelChunkWithLightPacket.java
@@ -66,4 +66,11 @@ public class ClientboundLevelChunkWithLightPacket implements Packet<ClientGamePa
     public ClientboundLightUpdatePacketData getLightData() {
         return this.lightData;
     }
+
+    // Paper start - Handle oversized block entities in chunks
+    @Override
+    public java.util.List<Packet<?>> getExtraPackets() {
+        return this.chunkData.getExtraPackets();
+    }
+    // Paper end - Handle oversized block entities in chunks
 }