code: public void destroy() throws SlickException {
  		for (int tx=0;tx<xcount;tx++) {
  			for (int ty=0;ty<ycount;ty++) {
  				Image image = images[tx][ty];
  				image.destroy();
  			}
  		}
  	}
docs: Destroy the image and release any native resources.
  Calls on a destroyed image have undefined results