Message-ID: <38637BBF.CC5A0C04@maths.unine.ch>
Date: Fri, 24 Dec 1999 14:57:19 +0100
From: Gautier <Gautier DOT deMontmollin AT maths DOT unine DOT ch>
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Subject: Re: 3D Problem
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

There is no 100% guarantee about a correct order with z-sorting.
If your object is convex or has similar sizes for faces it is OK,
otherwise there are surprises, whatever the criterion for z is...
You can have a case where A visually overlaps B; B, C; C, A; so
z-sorting always fails. You have to design you objects carefully...
My own engine does (still...) use z-sorting, so I have suffered
a bit with these problems... See http://members.xoom.com/gdemont/e3d.htm
HTH
-- 
Gautier