After getting some success with the BREP boolean algorithm next step should be  supporting all other kinds of surfaces. I decided to start with the NURBS surfaces because it is possible to represent almost any other surface like cylindrical, spherical, conical, torus and etc… by NURBS.  For NURBS evaluation a picked only available for javascript library: http://verbnurbs.com/.  Also I have compiled opennurbs (a NURBS library written in C++) to javascript. Still haven't decided which library to use. At that point, I had to implement the following in order to move on:

1. Enhance my BREP boolean algorithm to support curves and NURBS surfaces.
2. Trimmed by loops NURBS surface tessellation which is needed for visualization.  vernurbs is only able to tessellate un-treamed surfaces.