Generate 2D cross-section polygon from 3D mesh

Posted by nornagon on Stack Overflow See other posts from Stack Overflow or by nornagon
Published on 2010-05-09T11:05:37Z Indexed on 2010/05/09 11:08 UTC
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Filed under:

geometry

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3d

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2d

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graphics

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algorithm

I'm writing a game which uses 3D models to draw a scene (top-down orthographic projection), but a 2D physics engine to calculate response to collisions, etc. I have a few 3D assets for which I'd like to be able to automatically generate a hitbox by 'slicing' the 3D mesh with the X-Y plane and creating a polygon from the resultant edges.

Google is failing me on this one (and not much helpful material on SO either). Suggestions?

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