Path: utzoo!censor!geac!torsqnt!jarvis.csri.toronto.edu!clyde.concordia.ca!uunet!dg!mpogue
From: mpogue@dg.dg.com (Mike Pogue)
Newsgroups: comp.graphics
Subject: Re: Tesselating the sphere
Message-ID: <274@dg.dg.com>
Date: 26 Feb 90 20:59:52 GMT
References: <155@tacitus.tfic.bc.ca> <271@dg.dg.com> <1990Feb24.070934.4605@spectre.ccsf.caltech.edu>
Reply-To: uunet!dg!mpogue (Mike Pogue)
Organization: Data General, Westboro, MA.
Lines: 36


  At this point, I am not free to distribute the code (I'm still working 
on the article), however, as soon as I can, I will post it (if there is
interest).

  As several people who sent me personal replies mentioned, the code is
relatively simple.  Once you see what is going on, it's pretty simple
to see how the code does it.

  The trick is to start thinking in geodesic geometry.  The geodesic dome
was extensively studied by Bucky Fuller, and he has patents on several major
geodesic techniques (e.g. the "diamond" pattern you may have seen.  Hard to
describe, but suffice it to say that it is distinctive, and increases the
strength of a dome by using the "skin" to create two "virtual skins", an inner
and an outer skin.).

  My code avoids the easy way (generating coordinates directly from the plane
equations), and goes through geodesic coordinates and then spherical coordinates
first.

  In this way, you can easily apply the correction factors to make:

	a) a dome that uses the minimum number of different strut lengths
	b) a dome which is more densely tesselated near the sides, for
		greater strength
	c) ellipsoid and super-ellipsoid domes, for greater "headroom".

  I apologize for not answering mail directly, but my mailer is definitely 
broken, so I seem to be able to receive mail, but I can't reply.

  FOr those of you interested in domes, try "The DomeBook" and "DomeBook II".
I don't know if these are still in print, and I don't remember the authors
either.  

  Mike Pogue
  Spekaing for myself, not my company.,...