[vtkusers] Graph scaling question

[Tim Newsham]

Hi,  I have a graph of data that I'm using to generate a 
stick-ball graph.  I recently added a feature to scale the
source graph.  The net effect of this is to make a graph of
the same shape, but with smaller balls and sticks.  That all
works pretty well.  However, I would prefer that the interaction
of the model appear the same before and after scaling..  By
this I mean, the graph shouldnt appear to move, and the interactor
should still rotate around the same point.  

What transformations would I need to perform to keep the interaction
consistent?  I tried scaling the camera's position, but this didnt
seem to keep the graph centered in the same position on the screen.

Tim N.