[glassner at parc.xerox.com: Re: polygon smoothing]

[mbp]

From: Andrew Glassner <glassner at parc.xerox.com>
To: mbp at geom
Subject: Re: polygon smoothing
Date: 	Thu, 13 May 1993 11:00:22 PDT


Mark:

Done.  It's called smooth.tar.Z.  The archive contains:

driver.c       A little driver to make a quad file and show how to use the package
gsmooth.c      The smoothing package
gsmooth.h      The header (clients need this)
smoothquads.c  The client for smoothing .quad files 
Makefile       Makes 'smoothquads' and 'driver'
normals.tex    The latex source for a Graphics Gems description of this package
normals.bib    The bibtex bibliography 

I'm including the Gems description to give you an idea for what's going on; I
haven't polished it yet, so please don't distribute it.  I'll be sending this
to Paul Heckbert (editor of Gems IV), but it's up to him to accept it or not.

I wrote this because I'm always shipping polygon files over to geomview, and
then wishing I could view them smooth-shaded.  Ideally, I'd like to have a 
pop-up panel with a button titled "Make Vertex Normals" that I could just click
and get vertex normals.  It would have an on/off button for edge preservation,
and text (number) fields for the edge preservation threshold and fuzz percentage.
Since I didn't know how to do that, I wrote this standalone package that does
the same things on a .quad file.

Note that I've added a fuzz threshold option to smoothquads beyond the help
message I sent you yesterday.  It used to be a #define, but I thought a dynamic
computation would be more robust in a general setting.

Let me know if there's anything I can do to make this more attractive to you;
I'd love to see it inside geomview!

-Andrew