/// <summary>
 /// Initializes map block with 4 NONEXISTENT entrances and coordinates.
 /// </summary>
 /// <param name="x">X coordinate of this block.</param>
 /// <param name="y">Y coordinate of this block.</param>
 public MapBlock(int x, int y)
 {
     entrances = new Entrance[4];
     for (int i = 0; i < entrances.Length; i++)
     {
         entrances[i] = new Entrance();
     }
     this.x = x;
     this.y = y;
 }
 /// <summary>
 /// Creates OPEN entrance in given direction.
 /// </summary>
 /// <param name="direction">Direction in which entrance will be created.</param>
 public void CreateEntrance(Direction direction)
 {
     entrances[(int)direction] = new Entrance(EntranceState.OPEN);
 }