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From: bennett@sgi.com (Jim Bennett)
Newsgroups: comp.sys.sgi
Subject: Re: Gouraud shading bug(?) on 4D20G under 3.3.2
Message-ID: <1991Apr18.170720.17960@odin.corp.sgi.com>
Date: 18 Apr 91 17:07:20 GMT
References: <1991Apr17.205152.21270@sun1.ruf.uni-freiburg.de>
Sender: news@odin.corp.sgi.com (Net News)
Distribution: comp
Organization: Silicon Graphics, Inc., Mountain View, CA
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In article <1991Apr17.205152.21270@sun1.ruf.uni-freiburg.de> ra@sun1.ruf.uni-freiburg.de (Christoph Ramshorn) writes:
>
>
>	We recently upgraded to 3.3.2 on our 4D20G and have a problem with
>Gouraud shading since: some triangles are rendered in green or magenta hues
>regardless of their actual color; the edges of those triangle edges are colored
>correctly, though.  Which triangles show those wrong colors depends on light
>source position (infinitely distant lights used), but the effect does not seem
>to follow any rule. This bug(?) is also observable the "flip (martini, x29,
>etc.)" demos.

I tried running flip on a similar configuration (my machine was a GR1.2,
a later rev of the graphics board), and I didn't see any problem.  I
haven't received any bug reports like this from the field.

Is any one else out there experiencing a problem like this?

>Christoph Ramshorn, Geologisches Institut, Albertstr.23-B
>D-7800 Freiburg i.Br., West Germany
>ra@trias.geologie.uni-freiburg.de
>Phone +49 761 203 2408  Fax +49 761 203 2463

Jim Bennett				(bennett@sgi.com)