From: tlenatNOSPAM AT flashnet DOT it (Tiziano Lena)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Allegro - Triangle bug?
Date: Thu, 21 May 1998 19:19:20 GMT
Organization: Customer of Flashnet S.p.A. - http://www.flashnet.it
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To: djgpp AT delorie DOT com
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>> Hi!
>> Has the triangle(...) call any known bug?
>> I ported my Djgpp 3d engine to Djgpp+Allegro (3.0 + WIP) and the
>> program sometimes crashes (SIGFPE) when I am close to objects.
>> In gdb I made a disassemb <eip> and saw that it points to the triangle
>> routine...
>
>are you doing any clipping? Are any of the Z coords negative, or very
>close to 0? You should clip to a Z=1 plane before drawing.

I use the Sutherland algo for clipping to a z-near plane.
I tested the clipping with my old polyfillers and it seems to work...
But maybe there is a bug somewhere else... :-(