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Date: Tue, 16 Apr 1996 16:19:44 +22305133 (EDT)
From: Michael Kotelyanskii <kotelyan ":at:" che.udel.edu>
Subject: Re: CCL:Inside or outside of a polyhedron 
To: "W. Todd Wipke" <wipke _-at-_)SECS.UCSC.EDU>
Cc: chemistry /at\ccl.net
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OK, here is another one:

1) Make a Delone tesselation for the polyhedron vortices.

If it is convex, all Delone simplexes (tetrahedra) are inside
the polyhedron.
In this case if your point is inside of any of the simplexes (simplex is
a tetrahedron - so check is simple (center of tetrahedron is always
inside, connect center with your point and see wether the border is crossed)
it is inside polyhedron.

If polyhedron is not convex, there will be Delone simplexes connecting
vortices which are entirely outside the polyhedron, and they can be excluded

I believe it should work
Mike


Michael Kotelyanskii PhD
Department of Chemical Engineering
University of Delaware                          kotelyan ":at:" che.udel.edu
Newark DE 19716