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From: pmoran@m.cs.uiuc.edu
Newsgroups: comp.graphics
Subject: Re: How to determine 4 points in a 3D p
Message-ID: <4400075@m.cs.uiuc.edu>
Date: 31 Oct 90 03:56:00 GMT
References: <31644@netnews.upenn.edu>
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Nf-From: m.cs.uiuc.edu!pmoran    Oct 30 21:56:00 1990



>  I am looking for the algorithm (pseudocode is fine) to determine any 4 given
> abitrary points p(x,y,z) that lie in the same plane...
> e.g. The algorithm should work for the following points ..

> ...

Another variation to do it with determinants:

	| p1x p1y p1z 1 |
	| p2x p2y p2z 1 | = 0  if the points are coplanar
	| p3x p3y p3z 1 |
	| p4x p4y p4z 1 |

Pat Moran
University of Illinois at Urbana-Champaign
student--no disclaimer required