Subject: Re: CCL:Inside or outside of a polyhedron

From: [email-masked] (Brian W. Beck)
Date: Tue, 16 Apr 1996 08:35:45 -0700 (PDT)

Alexander Golbraikh wrote:
: 
: 
: 
: Take any ray beginning at the given point. Count the number of
: points of intersection of this ray with polyhedron surface. If it is
: even, then the point is outside the polyhedron, if it is odd, then inside.
: One precaution: the ray may slide on some edges of the polyhedron.
: 
: Best regards,
: Alexander Golbraikh
: 
: 
       ^ /
       |/
       <     As you say, the ray may slide. The "o" point at the left is
       |\    outside the "polyhedron" yet passes through the polyhedron
       | \   surface only once if you send the ray only through the vertices
       o  \  defined by... say the Calphas of a protein.

	-Brian
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