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From: payne@hyperion.loni.ucla.edu (Bradley Payne)
Newsgroups: comp.graphics.visualization
Subject: Re: Marching Cubes
Summary: fix Marching Cubes with Marching Tetrahedra!
Keywords: marching cubes, isosurface
Message-ID: <2551@lee.SEAS.UCLA.EDU>
Date: 25 Apr 91 19:00:49 GMT
References: <3871@texsun.Central.Sun.COM> <1991Apr24.211855.11705@rice.edu> <1991Apr25.005705.16988@jarvis.csri.toronto.edu>
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Organization: Laboratory of Neuro Imaging, UCLA School of Medicine
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I've also encountered the hole problem with marching cubes.  This is caused
by an ambiguous case in the cube classification table.  One possible fix is
to decompose each cube into tetrahedra (there are methods which give 5 or 6
per cube), and then tile the tetrahedra, which don't have any ambiguous cases.
This does tend to give lumpier surfaces than marching cubes.

For details, see Payne&Toga,"Surface Mapping Brain Function on 3D Models",
CG&A vol 10 no 5, Sept 1990.  I've seen mention of a tetrahedral
approach in Siggraph course notes by Perlin, but I can't find the reference
at the moment.

Anybody patch this at the cube level? 

	- Brad
	payne@loni.ucla.edu