From fe680851757a281419cb6ce4de40016d32727b3e Mon Sep 17 00:00:00 2001
From: Spottedleaf <Spottedleaf@users.noreply.github.com>
Date: Tue, 1 Jan 2019 02:22:01 -0800
Subject: [PATCH] Add Heightmap API


diff --git a/src/main/java/net/minecraft/server/World.java b/src/main/java/net/minecraft/server/World.java
index f5156a89a5..57b0f1a38e 100644
--- a/src/main/java/net/minecraft/server/World.java
+++ b/src/main/java/net/minecraft/server/World.java
@@ -720,6 +720,7 @@ public abstract class World implements IEntityAccess, GeneratorAccess, IIBlockAc
         }
     }
 
+    public final int getHighestBlockY(final HeightMap.Type heightmap, final int x, final int z) { return this.a(heightmap, x, z); } // Paper - OBFHELPER
     public int a(HeightMap.Type heightmap_type, int i, int j) {
         int k;
 
diff --git a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
index 40ee34675c..457aa5a3f0 100644
--- a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
+++ b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
@@ -136,6 +136,28 @@ public class CraftWorld implements World {
         return world.getHighestBlockYAt(HeightMap.Type.LIGHT_BLOCKING, new BlockPosition(x, 0, z)).getY();
     }
 
+    // Paper start - Implement heightmap api
+    @Override
+    public int getHighestBlockYAt(final int x, final int z, final com.destroystokyo.paper.HeightmapType heightmap) throws UnsupportedOperationException {
+        this.loadChunk(x >> 4, z >> 4); // heightmap will ret 0 on unloaded areas
+
+        switch (heightmap) {
+            case LIGHT_BLOCKING:
+                return this.world.getHighestBlockY(HeightMap.Type.LIGHT_BLOCKING, x, z);
+            case ANY:
+                return this.world.getHighestBlockY(HeightMap.Type.WORLD_SURFACE, x, z);
+            case SOLID:
+                return this.world.getHighestBlockY(HeightMap.Type.OCEAN_FLOOR, x, z);
+            case SOLID_OR_LIQUID:
+                return this.world.getHighestBlockY(HeightMap.Type.MOTION_BLOCKING, x, z);
+            case SOLID_OR_LIQUID_NO_LEAVES:
+                return this.world.getHighestBlockY(HeightMap.Type.MOTION_BLOCKING_NO_LEAVES, x, z);
+            default:
+                throw new UnsupportedOperationException();
+        }
+    }
+    // Paper end
+
     public Location getSpawnLocation() {
         BlockPosition spawn = world.getSpawn();
         return new Location(this, spawn.getX(), spawn.getY(), spawn.getZ());
-- 
2.21.0