Free C/C++ geometric math library offering polygons, splines, subdivs..?

Free 3D geomet开发者_开发问答ric math library recommendations which offering polygon, spline, subdivs..?

I prefer open-source and BSD like license library.

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For polygon meshes (and subd) take a look at OpenMesh.

For polygon manipulation CGAL is king, but be aware of it's restrictive licensing.

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What do you think about this: Cairo or Qt?

It would be helpful, if you gave some context.