[vtkusers] handle right mouse click

[Mark Wyszomierski]

Hi,

I have an mfc app similar to the vtk MDI MFC example. I can never
generate WM_RBUTTONDOWN messages though. I tried calling
InstallMessageProcOff() through my interactor like the documentation
says, but still no messages are generated. I have a WindowProc()
procedure - no messages there - I tried adding mfc's right click
function handler - no messages there.

I've seen this problem on the mailing list with no solution - what can
be done to get a chance to process this message ourselves before the
interactor takes over?

Thanks
Mark