Editing NURBS Booleans

Non-Uniform Rational B-Splines are the dominant geometric representation format in Computer Aided Design.  BRL-CAD's support for these primitives is relatively recent, and while we can raytrace them we do not have the ability to perform operations such as surface/surface intersection calculations.  These abilities are fundamental to a wide variety of editing operations and essential to the process of converting implicit-primitive based boolean geometry trees to evaluated NURBS models.

This task would target the problem of implementing an algorithm to calculate surface/surface intersection for general NURBS surfaces.  These guys implemented something very similar although their implementation was not robust: http://www.cs.unc.edu/~geom/CSG/boole.html These guys followed that work and implemented a robust solution, but killed performance: http://www.cs.unc.edu/~geom/ESOLID/ (Note that while the papers are excellent references from which to get ideas, the source code from these efforts is not license compatible with BRL-CAD.) You will need to be very careful about tolerances and tolerance tracking without resorting to fixed-precision arithmetic. There are a variety of other research papers on the surface/surface intersection problem - students interested in this topic should discuss it with developers on the IRC channel or via email.

=References=

* src/librt/primitives/brep
* src/librt/primitives/bspline
* src/other/openNURBS
* src/librt/opennurbs_ext.*
* include/opennurbs_ext.h
* include/raytrace.h
* include/rtgeom.h

=Requirements=

*Familiarity with C++
*Solid mathematical foundations