[Paraview] Plugin access to render window

[Thomas D. Uram]

Hi:

I'm writing a plugin for Paraview3 that wants to get access to pixel 
data from the render window.  I've been looking for some way to get a 
pointer to the render window so I could add an observer with something like

renderWindowPointer->AddObserver("EndEvent",myRenderEventHandler)

I've tried to find a mechanism for getting a pointer to the render 
window (e.g., retrieve a vtkSMRenderModuleProxy from the 
vtkSMProxyManager), but so far have not had any luck.

I'd be grateful for suggestions as to how I should proceed.

Thanks,
Tom Uram