[vtkusers] custom renderer in vtkRenderView

[David Feng]

I'd like to write a view that uses a custom renderer, but right now it's 
not clear that there's a way to override the renderer created by default 
for a vtkRenderView.  The custom renderer redirects the rendering into a 
frame buffer object and draws the output onto screen-filling quad. 

Is there a way to plug this renderer into vtkRenderView?

Thanks,
David