Re: Finding edges of a given polyhedra in 3D

klaus hoffmann wrote:
Patricia Shanahan wrote:
.....
Similarly, for the 2D polygon, I don't think the original diagonal
crossing idea works for non-convex:

A------B
| |
| C--D
| |
| E--F
| |
G------H

The lines CF and DE intersect outside the area of the polygon, but
neither is an edge.

Patricia
The OP has only the corners of a 3d-polyhedron. I don't know how they specify a nonconvex figure


Perhaps I should turn my question around. Suppose some of the vertices
are inside the convex hull of the other vertices, as in my figure. What
is the OP supposed to do in that situation, or is it prohibited?

If the OP is allowed to drop points that are inside the convex hull, or
if the polygon or polyhedron is guaranteed to be convex, then the OP is
asking for the convex hull of a finite set of points in 2 or 3
dimensions, well studied problems with published algorithms.

Patricia
.

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