TerrainHeight.java

import java.util.HashMap;

public class TerrainHeight{
  public HashMap<Integer, Float> terrain;
  
  public TerrainHeight(){
     terrain = new HashMap<>();
  }
  
  public void storeHeight(int x, int y, float value){
    terrain.put(hashKey(x, y), value);     
  }
  
  public float getHeight(int x, int y){    
    return terrain.get(hashKey(x, y));  
  }
    public Integer hashKey(int x, int y){
        return 5000 * y + x;
    }
}