public void invalidate(int attribs) {
			valid[attribs] = false;       /* Invalidate original image and */
			if (image[attribs] != null) image[attribs].flush();
			valid[attribs + 1] = false;   /* all flipped versions in cache */
			if (image[attribs + 1] != null) image[attribs + 1].flush();
			valid[attribs + 2] = false;
			if (image[attribs + 2] != null) image[attribs + 2].flush();
			valid[attribs + 3] = false;
			if (image[attribs + 3] != null) image[attribs + 3].flush();
		}