gluNurbsSurface(theNurb,8,knots,8,knots,4*3,3,&ctlpts[0][0][0],4,4,GL_MAP2_VERTEX_3);

Why can I used more than 8.?

Can the above function plot the surface of a sphere.

Suppose I have a 3d equation can I use gluNurbsSurface to generate the surface?

Does any one knows where I could find examples of different surface been draw/

Thank you