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From: thant@horus.sgi.com (Thant Tessman)
Newsgroups: comp.sys.sgi
Subject: Re: questions about drawing polygons
Summary: half or third?
Keywords: polygons
Message-ID: <33321@sgi.SGI.COM>
Date: 22 May 89 15:25:30 GMT
References: <9753@watcgl.waterloo.edu> <33129@sgi.SGI.COM> <9803@watcgl.waterloo.edu>
Sender: daemon@sgi.SGI.COM
Distribution: comp
Organization: Silicon Graphics, Inc., Mountain View, CA
Lines: 21

In article <9803@watcgl.waterloo.edu>, jdchrist@watcgl.waterloo.edu (Dan Christensen) writes:
> [stuff omitted throughout]
> 
> In article <33129@sgi.SGI.COM> thant@horus.SGI.COM (Thant Tessman) writes:
> >

> 
> >> 2) I am trying to draw a large mesh of shaded triangles.  The GT
> >>    Library has routines for drawing triangular meshes.  These
> >>    routines look like they would speed up drawing significantly because
> >>    only one third of the lighting calculations need to be done and one
> >              ^^^^^ 
> >One half.  In a single strip, each point is sent down once instead of twice
> >(not including the end points).  In a connected row of strips each point is 
> >sent down twice instead of four times.
> 
> I think it is one third, for a long strip.  To draw this using the

You're right.  I was thinking in comparison to quadrangles.

thant@sgi.com