[vtkusers] problems with vtkImagePlaneWidget

[dean.inglis at camris.ca]

>My first solution requires a hammer and a chainsaw, so we'll skip to the
>second.  With the vtkImagePlaneWidget in latest CVS (I don't know when
>this was added, Dean?), 

Well, it looks like Sebastien Barre started this back in October:
vtkImagePlaneWidget.h, rev. 1.37.

I haven't tried this button/key modifier stuff yet since all I have 
now are 3 button wheel mice. Looking at Sebastien's changes though,
it appears that one has to sacrifice cursoring, or window levelling
in favour of one of the slice motions (pan, scale, rotate, spin, push etc.).  
The function AdjustState, wherein modifier keys are checked, is only 
called by StartSliceMotion and not StartCursor or StartWindowLevel.  
I think to do what is being suggested would require some form of 
AdjustState function for all Start* methods wherein modifiers could 
be checked.  In the meantime, assigning functionality to two button 
mice must be done programmatically.

I may look into this when I have time, or could help out as required if
someone else wants to give it a shot....

Dean