[vtkusers] Get vertex coordinates in world coordinates

[Ming Xie]

Hi,

I used vtkCubeSource to create a box. The box is rotated with one of the
rotation functions of vtkActor. I need to get the coordinates of the
vertices in the world coordinate system, after rotation. I tried to query
the mapper, but I end up getting the coordinates before rotation. What is
the best way to get the final coordinates of the points?

Thanks,

Ming