[Fluxus] nurbs problems

[gabor papp]

> build-nurbs-plane generates funny shapes sometimes
i committed a quick fix for this into the cvs.

as far as i understand the problem lies in the NURBSPrimitive render 
function. gluNurbsSurface is called with two stride values in the 
parametric u and v direction. this is m_VCVCount*m_Stride for u and 
m_Stride for v now, but i think they should be swapped. when i changed 
this, build-nurbs-plane started to work fine, but build-nurbs-sphere was 
ruined. i believe the reason for this is the additional control points 
used for the nurbs sphere, which causes that the value of m_VCVCount 
will be wrong. i think it would be cleaner to use as many control points 
as requested by the user, which would include the additional control 
points as well.

with a simple hack i swapped the build-nurbs-plane u and v loops to suit 
the exchanged gluNurbsSurface stride offsets, and it seems to work ok. 
although this solution just increases the mess around this problem 
probably :).

best,
gabor