[vtkusers] Question about normal calc in vtkContourFilter

[Weiguang Guan]

Hi everyone,

Does anyone know how to use vtkContourFilter to get a surface so that each
vertex of the mesh has not only coordinates but normal as well? I look at
the manual and cannot figure out what should be passed in to 
                    SetComputeNormals (int)
Another question is how the normals are calculated, are they determined by
vertices' coordinates? Can I use gradient instead of normal in lighting
computation? Any hint will be appreciated, better with sample code. 

Thanks,
Weiguang

--
Weiguang Guan, Schrodinger Inc | Email: weiguang at schrodinger.com
Tel: 503-299-1150 ext. 128 (O)