If I pick against the polygonal geometry output by vtkContourFilter or vtkMarchingCubes (using
vtkPointPicker), what point is returned? Is it the exact point intersected by the intersecting ray
or the nearest vertex of the triangle (or polygon)? Looking at the code, it seems like the closest
vertex (as the intersecting module goes through the list of points in hte mapper geometry).

Also, what is the distinction between world coordinates and mapper coordinates? Again, w.r.t. the
above filters are they the same?

Thanks.

-- krs

-- 
K.R.Subramanian                           Phone: (704) 547-4872
Department of Computer Science            FAX:   (704) 547-3516
UNC Charlotte                             Email: krs@cs.uncc.edu
9201 Univ. City Blvd.                     WWW: http://www.cs.uncc.edu/~krs
Charlotte, NC 28223-0001