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From: musgrave-forest@CS.YALE.EDU (F. Ken Musgrave)
Newsgroups: comp.graphics
Subject: Lunar Distortions
Message-ID: <27332@cs.yale.edu>
Date: 17 Nov 90 14:00:14 GMT
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  Here's another little question spawned by moon-renderings:

  A very wide-angle view of a scene (i.e., a landscape), with a sphere
(i.e., a moon) in an extreme corner of the image, sports one very distorted
sphere in the image, when rendered using the standard virtual-screen model
for ray tracing.  (See the cover of Jan. '89 IEEE CG&A for an example.)

  Seems that this is a version of the sphere-to-plane mapping problem, and
therefore inadmissible to a non-distorting solution.

  Can anyone out there prove this conjecture right or wrong, or demonstrate
some nice workaround?

							Ken
-- 
		The Fundamental Dilemma of Existentialism:

	Eschew obfuscation.			Ignore alien orders.