Fixed trees being invisible under certain circumstances. Thanks Zeerix!

src/main/java/net/minecraft/server/BlockSapling.java

@@ -0,0 +1,84 @@
+package net.minecraft.server;
+
+import java.util.Random;
+
+import org.bukkit.BlockChangeDelegate; // CraftBukkit
+
+public class BlockSapling extends BlockFlower {
+
+    protected BlockSapling(int i, int j) {
+        super(i, j);
+        float f = 0.4F;
+
+        this.a(0.5F - f, 0.0F, 0.5F - f, 0.5F + f, f * 2.0F, 0.5F + f);
+    }
+
+    public void a(World world, int i, int j, int k, Random random) {
+        super.a(world, i, j, k, random);
+        if (world.getLightLevel(i, j + 1, k) >= 9 && random.nextInt(30) == 0) {
+            int l = world.getData(i, j, k);
+
+            if ((l & 8) == 0) {
+                world.setData(i, j, k, l | 8);
+            } else {
+                this.b(world, i, j, k, random);
+            }
+        }
+    }
+
+    public int a(int i, int j) {
+        j &= 3;
+        return j == 1 ? 63 : (j == 2 ? 79 : super.a(i, j));
+    }
+
+    public void b(World world, int i, int j, int k, Random random) {
+        int l = world.getData(i, j, k) & 3;
+
+        world.setRawTypeId(i, j, k, 0);
+
+        // CraftBukkit start - fixes client updates on recently grown trees
+        boolean grownTree;
+        BlockChangeWithNotify delegate = new BlockChangeWithNotify(world);
+
+        if (l == 1) {
+            grownTree = new WorldGenTaiga2().generate(delegate, random, i, j, k);
+        } else if (l == 2) {
+            grownTree = new WorldGenForest().generate(delegate, random, i, j, k);
+        } else {
+            if (random.nextInt(10) == 0) {
+                grownTree = new WorldGenBigTree().generate(delegate, random, i, j, k);
+            } else {
+                grownTree = new WorldGenTrees().generate(delegate, random, i, j, k);
+            }
+        }
+
+        if (!grownTree) {
+            world.setRawTypeIdAndData(i, j, k, this.id, l);
+        }
+        // CraftBukkit end
+    }
+
+    protected int b(int i) {
+        return i & 3;
+    }
+
+    // CraftBukkit start
+    private class BlockChangeWithNotify implements BlockChangeDelegate {
+        World world;
+
+        BlockChangeWithNotify(World world) { this.world = world; }
+
+        public boolean setRawTypeId(int x, int y, int z, int type) {
+            return world.setTypeId(x, y, z, type);
+        }
+
+        public boolean setRawTypeIdAndData(int x, int y, int z, int type, int data) {
+            return world.setTypeIdAndData(x, y, z, type, data);
+        }
+
+        public int getTypeId(int x, int y, int z) {
+            return world.getTypeId(x, y, z);
+        }
+    }
+    // CraftBukkit end
+}