[vtkusers] Rotate around a specific point

[Gendron, Patrick]

Hi everyone!

I'd like to know if it is possible to specify a point that would be consider
like the center of rotation while interacting with the mouse. All I've found
for now, is the possibility to turn around the screen center or to turn
every actor individually. Is there an object or a method to call to make it
possible? Or maybe an example to make my own Interactor.

Thanks!

Patrick Gendron