From 307214251375ab411861fbb733550969e88343cc Mon Sep 17 00:00:00 2001
From: Leijurv <leijurv@gmail.com>
Date: Sun, 5 Aug 2018 10:06:20 -0400
Subject: [PATCH] don't read empty chunks

---
 .../java/baritone/bot/chunk/CachedRegion.java | 26 ++++++++++++++-----
 1 file changed, 19 insertions(+), 7 deletions(-)

diff --git a/src/main/java/baritone/bot/chunk/CachedRegion.java b/src/main/java/baritone/bot/chunk/CachedRegion.java
index baa3f771..ebee5808 100644
--- a/src/main/java/baritone/bot/chunk/CachedRegion.java
+++ b/src/main/java/baritone/bot/chunk/CachedRegion.java
@@ -53,10 +53,11 @@ public final class CachedRegion implements ICachedChunkAccess {
     @Override
     public final void updateCachedChunk(int chunkX, int chunkZ, BitSet data) {
         CachedChunk chunk = this.getChunk(chunkX, chunkZ);
-        if (chunk == null)
+        if (chunk == null) {
             this.chunks[chunkX][chunkZ] = new CachedChunk(chunkX, chunkZ, data);
-        else
+        } else {
             chunk.updateContents(data);
+        }
     }
 
     private CachedChunk getChunk(int chunkX, int chunkZ) {
@@ -99,6 +100,7 @@ public final class CachedRegion implements ICachedChunkAccess {
             Path regionFile = getRegionFile(path, this.x, this.z);
             if (!Files.exists(regionFile))
                 return;
+
             byte[] decompressed;
             try (FileInputStream in = new FileInputStream(regionFile.toFile())) {
                 decompressed = GZIPUtils.decompress(in);
@@ -109,18 +111,28 @@ public final class CachedRegion implements ICachedChunkAccess {
 
             for (int z = 0; z < 32; z++) {
                 for (int x = 0; x < 32; x++) {
-                    CachedChunk chunk = this.chunks[x][z];
-                    if (chunk != null) {
-                        int index = (x + (z << 5)) * CachedChunk.SIZE_IN_BYTES;
-                        byte[] bytes = Arrays.copyOfRange(decompressed, index, index + CachedChunk.SIZE_IN_BYTES);
+                    int index = (x + (z << 5)) * CachedChunk.SIZE_IN_BYTES;
+                    byte[] bytes = Arrays.copyOfRange(decompressed, index, index + CachedChunk.SIZE_IN_BYTES);
+                    if (isAllZeros(bytes)) {
+                        this.chunks[x][z] = null;
+                    } else {
                         BitSet bits = BitSet.valueOf(bytes);
-                        chunk.updateContents(bits);
+                        updateCachedChunk(x, z, bits);
                     }
                 }
             }
         } catch (IOException ignored) {}
     }
 
+    private static boolean isAllZeros(final byte[] array) {
+        for (byte b : array) {
+            if (b != 0) {
+                return false;
+            }
+        }
+        return true;
+    }
+
     /**
      * @return The region x coordinate
      */