From 87d59fdab40d8554fbc51db2b9b5f8428fdb01ca Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Mon, 10 Sep 2018 23:38:16 -0400
Subject: [PATCH] Prevent fluids from loading chunks - major performance boost

---
 ...ent-chunk-loading-from-Fluid-Flowing.patch | 79 +++++++++++++++++++
 1 file changed, 79 insertions(+)
 create mode 100644 Spigot-Server-Patches/0366-Prevent-chunk-loading-from-Fluid-Flowing.patch

diff --git a/Spigot-Server-Patches/0366-Prevent-chunk-loading-from-Fluid-Flowing.patch b/Spigot-Server-Patches/0366-Prevent-chunk-loading-from-Fluid-Flowing.patch
new file mode 100644
index 0000000000..946e85af90
--- /dev/null
+++ b/Spigot-Server-Patches/0366-Prevent-chunk-loading-from-Fluid-Flowing.patch
@@ -0,0 +1,79 @@
+From cc6b3fdf5dfb4cc3f86348dc98fcebeb545621b2 Mon Sep 17 00:00:00 2001
+From: Aikar <aikar@aikar.co>
+Date: Mon, 10 Sep 2018 23:36:16 -0400
+Subject: [PATCH] Prevent chunk loading from Fluid Flowing
+
+
+diff --git a/src/main/java/net/minecraft/server/FluidTypeFlowing.java b/src/main/java/net/minecraft/server/FluidTypeFlowing.java
+index 90ba7a346f..7f16dec688 100644
+--- a/src/main/java/net/minecraft/server/FluidTypeFlowing.java
++++ b/src/main/java/net/minecraft/server/FluidTypeFlowing.java
+@@ -186,7 +186,8 @@ public abstract class FluidTypeFlowing extends FluidType {
+                 EnumDirection enumdirection = (EnumDirection) entry.getKey();
+                 Fluid fluid1 = (Fluid) entry.getValue();
+                 BlockPosition blockposition1 = blockposition.shift(enumdirection);
+-                IBlockData iblockdata1 = generatoraccess.getType(blockposition1);
++                IBlockData iblockdata1 = generatoraccess.getTypeIfLoaded(blockposition1); // Paper
++                if (iblockdata1 == null) continue; // Paper
+ 
+                 if (this.a(generatoraccess, blockposition, iblockdata, enumdirection, blockposition1, iblockdata1, generatoraccess.b(blockposition1), fluid1.c())) {
+                     // CraftBukkit start
+@@ -213,7 +214,8 @@ public abstract class FluidTypeFlowing extends FluidType {
+         while (iterator.hasNext()) {
+             EnumDirection enumdirection = (EnumDirection) iterator.next();
+             BlockPosition blockposition1 = blockposition.shift(enumdirection);
+-            IBlockData iblockdata1 = iworldreader.getType(blockposition1);
++            IBlockData iblockdata1 = iworldreader.getTypeIfLoaded(blockposition1); // Paper
++            if (iblockdata1 == null) continue; // Paper
+             Fluid fluid = iblockdata1.s();
+ 
+             if (fluid.c().a((FluidType) this) && this.a(enumdirection, (IBlockAccess) iworldreader, blockposition, iblockdata, blockposition1, iblockdata1)) {
+@@ -331,11 +333,19 @@ public abstract class FluidTypeFlowing extends FluidType {
+                 BlockPosition blockposition2 = blockposition.shift(enumdirection1);
+                 short short0 = a(blockposition1, blockposition2);
+                 // CraftBukkit start - decompile errors
+-                Pair pair = (Pair) short2objectmap.computeIfAbsent(short0, (ix) -> {
+-                    IBlockData iblockdatax = iworldreader.getType(blockposition2);
++                // Paper start - avoid loading chunks
++                Pair<IBlockData, Fluid> pair = short2objectmap.get(short0);
++                if (pair == null) {
++                    IBlockData iblockdatax = iworldreader.getTypeIfLoaded(blockposition2);
++                    if (iblockdatax == null) {
++                        continue;
++                    }
+ 
+-                    return Pair.of(iblockdatax, iblockdatax.s());
+-                });
++                    pair = Pair.of(iblockdatax, iblockdatax.s());
++                    short2objectmap.put(short0, pair);
++
++                }
++                // Paper end
+                 // CraftBukkit end
+                 IBlockData iblockdata1 = (IBlockData) pair.getFirst();
+                 Fluid fluid = (Fluid) pair.getSecond();
+@@ -411,11 +421,16 @@ public abstract class FluidTypeFlowing extends FluidType {
+             BlockPosition blockposition1 = blockposition.shift(enumdirection);
+             short short0 = a(blockposition, blockposition1);
+             // CraftBukkit start - decompile errors
+-            Pair pair = (Pair) short2objectopenhashmap.computeIfAbsent(short0, (ix) -> {
+-                IBlockData iblockdatax = iworldreader.getType(blockposition1);
+-
+-                return Pair.of(iblockdatax, iblockdatax.s());
+-            });
++            // Paper start
++            Pair pair = (Pair) short2objectopenhashmap.get(short0);
++            if (pair == null) {
++                IBlockData iblockdatax = iworldreader.getTypeIfLoaded(blockposition1);
++                if (iblockdatax == null) continue;
++
++                pair = Pair.of(iblockdatax, iblockdatax.s());
++                short2objectopenhashmap.put(short0, pair);
++            }
++            // Paper end
+             // CraftBukkit end
+             IBlockData iblockdata1 = (IBlockData) pair.getFirst();
+             Fluid fluid = (Fluid) pair.getSecond();
+-- 
+2.18.0
+