From: tsa@cellar.org (The Silent Assassin) Subject: Questions about Plane Eqn method of Hidden Surface removal Organization: The Cellar BBS and public access system Lines: 18 What are the main advantages of this method? I have seen it described, and the algiorithm seems a little bit long. I developed my own method, which requires that the points be in a counter-clockwise order, and returns whether you are looking at the back or the front, similar to the plane eqn method. It uses few calculations however, basically it is several comparisons. The only disadvantage I see is that it must be done after the transformation from view coordinates to coordinates to display on the screen, which means that a little more calculation isneeded beforehand. My method basically figures out whether the points that will appear on the screen are clockwise or counterclockwise. When looking at the back of something, the points occur in an opposite direction from the front, so merely by figuring out which way the points go, you can tell whether you are looking at the back or front of a 2d polygon. Has anyone heard of this method before? It is so simple, I doubt i am the first to think of it. Libertarian, atheist, semi-anarchal Techno-Rat. I define myself--tsa@cellar.org