Well, the _easy_ way to do that is to do something like this - draw_surface_with_shading(); translate( 0.0, 0.0, -0.01 ); draw_surface_with_grey(); That doubles your drawing time, of course, but I don't see any other fairly easy way to do it... Marc --- Marc Andreessen, IBM AWD Austin, sergio at sergio.austin.ibm.com ---