if (pixel < map_size) return (int) ((generateMask (3) & rgb[pixel]) >> (3 * pixel_bits));
if (opaque || pixel >= map_size) return 255;
  public final int getAlpha (int pixel)  {    if (pixel < map_size)	    return (int) ((generateMask (3) & rgb[pixel]) >> (3 * pixel_bits));    			return 0;		}