draw_set_circle_precision(128); 

gpu_set_blendmode_ext(bm_inv_dest_color, bm_zero);

if (radius_outer > 0)
    draw_circle_color(x, y, radius_outer, c_white, c_white, false);


if (radius_inner > 0)
    draw_circle_color(x, y, radius_inner, c_black, c_black, false);
	
gpu_set_blendmode(bm_normal);