code: public Image getSubImage(int x, int y) {
  		init();
  		
  		if ((x < 0) || (x >= subImages.length)) {
  			throw new RuntimeException("SubImage out of sheet bounds: "+x+","+y);
  		}
  		if ((y < 0) || (y >= subImages[0].length)) {
  			throw new RuntimeException("SubImage out of sheet bounds: "+x+","+y);
  		}
  		
  		return subImages[x][y];
  	}
docs: Get the sub image cached in this sprite sheet
  
  @param x The x position in tiles of the image to get
  @param y The y position in tiles of the image to get
  @return The subimage at that location on the sheet