From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Jake Potrebic <jake.m.potrebic@gmail.com>
Date: Sat, 21 Aug 2021 18:53:03 -0700
Subject: [PATCH] Only capture actual tree growth


diff --git a/src/main/java/net/minecraft/world/level/block/grower/AbstractMegaTreeGrower.java b/src/main/java/net/minecraft/world/level/block/grower/AbstractMegaTreeGrower.java
index 3decfca75ae1ace3da8ff47815a47d84c2a86105..b1e4a84bc5351ffe472d8371565665148253ad8f 100644
--- a/src/main/java/net/minecraft/world/level/block/grower/AbstractMegaTreeGrower.java
+++ b/src/main/java/net/minecraft/world/level/block/grower/AbstractMegaTreeGrower.java
@@ -49,17 +49,25 @@ public abstract class AbstractMegaTreeGrower extends AbstractTreeGrower {
                 ConfiguredFeature<?, ?> worldgenfeatureconfigured = (ConfiguredFeature) holder.value();
                 BlockState iblockdata1 = Blocks.AIR.defaultBlockState();
 
+                // Paper start
+                final CaptureState captureState = new CaptureState(world).recordAndSetToFalse();
+                try (captureState) {
+                // Paper end
                 world.setBlock(pos.offset(x, 0, z), iblockdata1, 4);
                 world.setBlock(pos.offset(x + 1, 0, z), iblockdata1, 4);
                 world.setBlock(pos.offset(x, 0, z + 1), iblockdata1, 4);
                 world.setBlock(pos.offset(x + 1, 0, z + 1), iblockdata1, 4);
+                } // Paper
                 if (worldgenfeatureconfigured.place(world, chunkGenerator, random, pos.offset(x, 0, z))) {
                     return true;
                 } else {
+                    captureState.recordAndSetToFalse(); // Paper
+                    try (captureState) { // Paper
                     world.setBlock(pos.offset(x, 0, z), state, 4);
                     world.setBlock(pos.offset(x + 1, 0, z), state, 4);
                     world.setBlock(pos.offset(x, 0, z + 1), state, 4);
                     world.setBlock(pos.offset(x + 1, 0, z + 1), state, 4);
+                    } // Paper
                     return false;
                 }
             }
diff --git a/src/main/java/net/minecraft/world/level/block/grower/AbstractTreeGrower.java b/src/main/java/net/minecraft/world/level/block/grower/AbstractTreeGrower.java
index a743f36f2682a6b72ffa6644782fc081d1479eb7..1478483c0a5e35dfe0865ba5d819822765940dbf 100644
--- a/src/main/java/net/minecraft/world/level/block/grower/AbstractTreeGrower.java
+++ b/src/main/java/net/minecraft/world/level/block/grower/AbstractTreeGrower.java
@@ -41,7 +41,12 @@ public abstract class AbstractTreeGrower {
                 ConfiguredFeature<?, ?> worldgenfeatureconfigured = (ConfiguredFeature) holder.value();
                 BlockState iblockdata1 = world.getFluidState(pos).createLegacyBlock();
 
+                // Paper start - don't capture the change to air for tree blocks
+                final CaptureState captureState = new CaptureState(world).recordAndSetToFalse();
+                try (captureState) {
+                // Paper end
                 world.setBlock(pos, iblockdata1, 4);
+                } // Paper
                 if (worldgenfeatureconfigured.place(world, chunkGenerator, random, pos)) {
                     if (world.getBlockState(pos) == iblockdata1) {
                         world.sendBlockUpdated(pos, state, iblockdata1, 2);
@@ -49,7 +54,10 @@ public abstract class AbstractTreeGrower {
 
                     return true;
                 } else {
+                    captureState.recordAndSetToFalse(); // Paper - don't capture the change to air for tree blocks
+                    try (captureState) { // Paper
                     world.setBlock(pos, state, 4);
+                    } // Paper
                     return false;
                 }
             }
@@ -122,4 +130,29 @@ public abstract class AbstractTreeGrower {
         }
     }
     // CraftBukkit end
+    // Paper start
+    static class CaptureState implements AutoCloseable {
+        private final ServerLevel level;
+        private boolean previousCaptureTreeGeneration;
+        private boolean previousCaptureBlockStates;
+
+        CaptureState(net.minecraft.server.level.ServerLevel level) {
+            this.level = level;
+        }
+
+        CaptureState recordAndSetToFalse() {
+            this.previousCaptureTreeGeneration = this.level.captureTreeGeneration;
+            this.previousCaptureBlockStates = this.level.captureBlockStates;
+            this.level.captureTreeGeneration = false;
+            this.level.captureBlockStates = false;
+            return this;
+        }
+
+        @Override
+        public void close() {
+            this.level.captureTreeGeneration = this.previousCaptureTreeGeneration;
+            this.level.captureBlockStates = this.previousCaptureBlockStates;
+        }
+    }
+    // Paper end
 }