[vtkusers] Re: Newbie question re vtkImageClip

[Jeremy Winston]

Jeremy Winston wrote:
> 
>      I've skimmed the User's Guide & the textbook, but
> I'm still having trouble using vtkImageClip.  All I want
> to do is interactively zoom in on a ROI in a CT image
> (for the purpose of applying a contour filter only on the
> ROI).  [...]

OK, after wading through the Doxygen docs, I found this, in
the Member Data Documentation for the vtkSource class:

   int vtkSource::LegacyHack  
 
      Legacy method. This method was used by inmaging filters to change
   the UpdateExtent of their input so that the vtkImmageToImageFilter
   superclass would allocate a larger volume. Changing the UpdateExtent
   of your input is no longer allowed.        ^^^^^^^^^^^^^^^^^^^^^^^^^
   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Since vtkImageClip is clearly an imaging filter, this applies to it.
Does this mean that it is not possible to clip an image interactively
(short of writing one's own Execute() method)?

Any help/pointers appreciated.

TIA,
-Jeremy