From a55fa31b0d23301861e55b4c70ebee7ad66c519d Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Mon, 26 Nov 2018 19:44:01 -0500
Subject: [PATCH] Prevent rayTrace from loading chunks

ray tracing into an unloaded chunk should be treated as a miss
this saves a ton of lag for when AI tries to raytrace near unloaded chunks.

diff --git a/src/main/java/net/minecraft/server/World.java b/src/main/java/net/minecraft/server/World.java
index 7633a613..bc231c7f 100644
--- a/src/main/java/net/minecraft/server/World.java
+++ b/src/main/java/net/minecraft/server/World.java
@@ -932,7 +932,8 @@ public abstract class World implements IBlockAccess {
                 int i1 = MathHelper.floor(vec3d.y);
                 int j1 = MathHelper.floor(vec3d.z);
                 BlockPosition blockposition = new BlockPosition(l, i1, j1);
-                IBlockData iblockdata = this.getType(blockposition);
+                IBlockData iblockdata = this.getTypeIfLoaded(blockposition); // Paper
+                if (iblockdata == null) return null; // Paper
                 Block block = iblockdata.getBlock();
 
                 if ((!flag1 || iblockdata.d(this, blockposition) != Block.k) && block.a(iblockdata, flag)) {
@@ -1034,7 +1035,8 @@ public abstract class World implements IBlockAccess {
                     i1 = MathHelper.floor(vec3d.y) - (enumdirection == EnumDirection.UP ? 1 : 0);
                     j1 = MathHelper.floor(vec3d.z) - (enumdirection == EnumDirection.SOUTH ? 1 : 0);
                     blockposition = new BlockPosition(l, i1, j1);
-                    IBlockData iblockdata1 = this.getType(blockposition);
+                    IBlockData iblockdata1 = this.getTypeIfLoaded(blockposition); // Paper
+                    if (iblockdata1 == null) return null; // Paper
                     Block block1 = iblockdata1.getBlock();
 
                     if (!flag1 || iblockdata1.getMaterial() == Material.PORTAL || iblockdata1.d(this, blockposition) != Block.k) {
-- 
2.19.2