I'm hoping I've read the question right: you want to check if a given point is inside a shape; and that shape is specified as a list of vertices. The shape is bounded by (straight) lines that connect those vertices.

One approach is to consider drawing a line from your candidate point to infinity: then count the number of times it crosses the bounding lines of the shape. If the number of lines that it crosses is an odd number, then the point was inside the shape. (Infinity is any point outside the bounding box of the shape).

--Dave

In reply to Re: OT: point inside polyhedron test by dpuu
in thread OT: point inside polyhedron test by stu96art

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