Merge overlapping triangles into a polygon

Posted by nornagon on Stack Overflow See other posts from Stack Overflow or by nornagon
Published on 2010-05-12T08:16:51Z Indexed on 2010/05/12 12:54 UTC
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Filed under:

graphics

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math

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algorithms

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geometry

I've got a bunch of overlapping triangles from a 3D model projected into a 2D plane. I need to merge each island of touching triangles into a closed, non-convex polygon.

The resultant polygons shouldn't have any holes in them (since the source data doesn't).

Many of the source triangles share (floating point identical) edges with other triangles in the source data.

What's the easiest way to do this? Performance isn't particularly important, since this will be done at design time.

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