Maybe useful for rendering ? < robust solid NURBS ray tracing>

http://brlcad.org/

Tue, 2012/08/07 - 18:02.

After more than six months development, BRL-CAD 7.22.0 is now available! This is a substantial introduction of a new development line encompassing more changes than any prior version since BRL-CAD's release as free open source software. We have robust solid NURBS ray tracing, updated several geometry converters, worked on a new physics simulation system, made several improvements to BRL-CAD's extensive documentation resources, and provide a vastly improved installer for Mac OS X.