[vtkusers] a polyhedron is convex or non-convex

[PAUL]

I want to judge whether a polyhedron is convex or non-convex by an
algorithm. The algorithm is : if every vertex of the polyhedron is convex
then the polyhedron is convex.

For each vertex, there is at least three vertexes is adjacent to it. These
vertexes make up of a triangle which forms a plane. Because the direction of
the plane can be gotten by the order of three vertexes according to
right-hand-rule, the order of three vertexes must be counter-clockwise.  If
the vertex is above the plane, the vertex is convex. If not, the vertex is
non-convex.

But I cannot assure the order of three vertexes is counter-clockwise.

And have you a better way to the question?

Look forward to your reply again.

 

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