From f9f74a0da877e94b2da5d542475ea0e6f557b170 Mon Sep 17 00:00:00 2001
From: Camotoy <20743703+Camotoy@users.noreply.github.com>
Date: Fri, 25 Jun 2021 13:51:52 -0400
Subject: [PATCH] Determine chunk Y offset on Java packet processing thread

Should stop NullPointerExceptions if the session closes before chunks are processed
---
 .../translators/java/world/JavaChunkDataTranslator.java      | 5 ++++-
 .../main/java/org/geysermc/connector/utils/ChunkUtils.java   | 4 +---
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/connector/src/main/java/org/geysermc/connector/network/translators/java/world/JavaChunkDataTranslator.java b/connector/src/main/java/org/geysermc/connector/network/translators/java/world/JavaChunkDataTranslator.java
index 198a7e3fb..81f5c4db3 100644
--- a/connector/src/main/java/org/geysermc/connector/network/translators/java/world/JavaChunkDataTranslator.java
+++ b/connector/src/main/java/org/geysermc/connector/network/translators/java/world/JavaChunkDataTranslator.java
@@ -55,9 +55,12 @@ public class JavaChunkDataTranslator extends PacketTranslator<ServerChunkDataPac
         session.getChunkCache().addToCache(packet.getColumn());
         Column column = packet.getColumn();
 
+        // Ensure that, if the player is using lower world heights, the position is not offset
+        int yOffset = session.getChunkCache().getChunkMinY();
+
         GeyserConnector.getInstance().getGeneralThreadPool().execute(() -> {
             try {
-                ChunkUtils.ChunkData chunkData = ChunkUtils.translateToBedrock(session, column);
+                ChunkUtils.ChunkData chunkData = ChunkUtils.translateToBedrock(session, column, yOffset);
                 ChunkSection[] sections = chunkData.getSections();
 
                 // Find highest section
diff --git a/connector/src/main/java/org/geysermc/connector/utils/ChunkUtils.java b/connector/src/main/java/org/geysermc/connector/utils/ChunkUtils.java
index 9723cd53c..85b7f8600 100644
--- a/connector/src/main/java/org/geysermc/connector/utils/ChunkUtils.java
+++ b/connector/src/main/java/org/geysermc/connector/utils/ChunkUtils.java
@@ -81,10 +81,8 @@ public class ChunkUtils {
         return (yzx >> 8) | (yzx & 0x0F0) | ((yzx & 0x00F) << 8);
     }
 
-    public static ChunkData translateToBedrock(GeyserSession session, Column column) {
+    public static ChunkData translateToBedrock(GeyserSession session, Column column, int yOffset) {
         Chunk[] javaSections = column.getChunks();
-        // Ensure that, if the player is using lower world heights, the position is not offset
-        int yOffset = session.getChunkCache().getChunkMinY();
         ChunkSection[] sections = new ChunkSection[javaSections.length - yOffset];
 
         // Temporarily stores compound tags of Bedrock-only block entities