public int[][] asIntegerGrid() {
		int[][] grid = new int[2 * height + 1][2 * width + 1];
		for(int y = 0; y < height; y++) {
			for(int x = 0; x < width; x++) {
				grid[2 * y + 1][2 * x + 1] = 1;
				
				if(passable(x, y, Direction.UP   )) { grid[2 * y    ][2 * x + 1] = 1; }
				if(passable(x, y, Direction.DOWN )) { grid[2 * y + 2][2 * x + 1] = 1; }
				if(passable(x, y, Direction.LEFT )) { grid[2 * y + 1][2 * x    ] = 1; }
				if(passable(x, y, Direction.RIGHT)) { grid[2 * y + 1][2 * x + 2] = 1; }
			}
		}
		return grid;
	}