Heightmap.java

/* Copyright (c) 2012 Jesper Öqvist <jesper@llbit.se>
 *
 * This file is part of Chunky.
 *
 * Chunky is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Chunky is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with Chunky.  If not, see <http://www.gnu.org/licenses/>.
 */
package se.llbit.chunky.world;

import java.util.HashMap;
import java.util.Map;

/**
 * Chunk heightmap.
 *
 * @author Jesper Öqvist <jesper@llbit.se>
 */
public class Heightmap {

  private Map<ChunkPosition, ChunkHeightmap> map = new HashMap<>();

  /**
   * Set height y at (x, z).
   */
  public synchronized void set(int y, int x, int z) {
    ChunkPosition cp = ChunkPosition.get(x >> 5, z >> 5);
    ChunkHeightmap hm = map.get(cp);
    if (hm == null) {
      hm = new ChunkHeightmap();
      map.put(cp, hm);
    }
    hm.set(y, x & 0x1F, z & 0x1F);
  }

  /**
   * @return Height at (x, z)
   */
  public synchronized int get(int x, int z) {
    ChunkPosition cp = ChunkPosition.get(x >> 5, z >> 5);
    ChunkHeightmap hm = map.get(cp);
    if (hm == null) {
      hm = new ChunkHeightmap();
      map.put(cp, hm);
    }
    return hm.get(x & 0x1F, z & 0x1F);
  }

}