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.

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

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

What do you think about this: Cairo or Qt?

It would be helpful, if you gave some context.