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From: CHETAN@rcgl1.eng.ohio-state.edu (Chetan Rastogi)
Newsgroups: comp.graphics
Subject: Angle between adjacent faces in a B-rep/polyhedral model
Message-ID: <6197@quanta.eng.ohio-state.edu>
Date: 20 Nov 90 18:35:28 GMT
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Organization: Ohio State University
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Hi Folks,

I am trying to do some geometric inferencing using a B-rep solid modeler. For
the moment assume that I am dealing only with plane faces.

PROBLEM:
For adjacent faces, I want to characterize the adjacency relation as convex or
concave.  ( depending upon whether the exterior angle is >= 180 or not).  All I
have explicitly defined are the face normals.  Does anyone know of an algorithm
for doing this in a relatively 'clean' fashion.  Any help will be a lifesaver

Please email, as I do not read this newsgroup very often.


Chetan Rastogi
Department Of Mechanical Engineering
The Ohio State University