Re: Finding edges of a given polyhedra in 3D

macio wrote:
Hello,

I have a problem to solve.

How can I find the edges of a polyhedra in 3D having only coordinates
of its vertices?
All the pairs of the vertices constitute corresponding line segments.
Some of them are diTetrahedronagonals and some of them are edges. I have to
distinguish them based only on the vertices data.

I searched a little and found no solution. I intended only very heavy
algorithm in 2D which consist on finding which of the line segments
intercept with each other in the area of the polyhedra (based on this I
could decide which is diagonal which is edge). This doesn't work of
course in 3D.

regards


A simple way of representing the polyhedron is as union of tetrahedra. You might take the middle of each pair of the vertices and check whether it is in the interior any tetrahedron (taking all four-tuples). This should give an (quite slow) algorithm to start with.
hth
Klaus

.

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