[vtkusers] Unused filter output

[Geoff Smith]

Hi,

I'm having a few problems getting to grips with the pipeline execution. 
Is it possible to have a filter which takes an input but its output will 
never go to a mapper or actor? I want to clip some polydata and use the 
results of this to perform registration. However, I don't want the 
clipping to show in the render window, I just want to use the clipped 
data when I perform registration. I've looked through the VTK user 
guide, but I can't figure out if this is possible... does anyone know 
what I can do or can point me in the right direction somehow?

Many thanks!

Geoff