[vtkusers] problem with GetEventPosion

[Binjie Qin]

Hi vtkuser:
   I have had problem with vtkRenderWindowInteractor's function, GetEventPosion(), in picking the event position (such mouse's leftbutton down)in render window's screen display coordinate.
   Due to new implementation of vtkRenderWindowInteractor in vtk4.2, the Position gotted is not actually the event position in window's screen display coordinate when actor in render window was scaled or rotated.
   How to get the position at render window's sreen disply coordinate using GetEventPosion() function?
   Any help?
   Thanks in advance!
                                                                 bjqin at SJTU in China