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From: randy@aplcomm.jhuapl.edu (RANDALL SCHRICKEL (NCE) x7661)
Newsgroups: comp.graphics,comp.sys.sgi
Subject: Triangulating non-planar surfaces
Keywords: triangulation, fea
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Date: 24 Jul 90 20:39:35 GMT
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Actually, I know how to do that. What I really need to know is how to create
interior points for a non-planar surface that will let me triangulate it into
lots of little polygons, so the generated surface will look smooth.  My
specific application is a filled spinning globe. Currently I only show the
outlines of continents; I would like to fill them in. I CAN triangulate the
x,y,z of the outlines, but that's not enough. I need to introduce lots of
interior points to the outlines so that small triangles will be produced.
This is like a finite element analysis problem, but the FEA stuff I've seen
is only good for planar polygons. Is there a method for generating interior
points to a curved surface? Or do I compute the interior points in 2-D and
then do the triangulation in 3-D? Pointers to references, ideas, or code
(of course) would be most appreciated.
--
	Randy Schrickel randy@aplcomm.jhuapl.edu
	Johns Hopkins Applied Physics Lab
	Laurel, MD 20723
	"Life goes on, long after the thrill of living has gone."