[vtk-developers] GUISupport growth?

[Brad King]

Clinton Stimpson wrote:
>> From: Michael Dussere <dussere at labri.fr>
>> I'm using the QVTKWidget from the CVS-version library QVTK. I found in 
>> the example GUI/Qt/Events there are two classes (vtkEventQtSlotConnect 
>> and vtkQtConnection) for mixing the events of Qt and VTK (coming from 
>> Sandia like QVTKWidget). I wonder why the two classes have not been 
>> inserted directly in the QVTK library, it would be great.
> 
> So there's this class in the examples which connects any VTK event to 
> any Qt slot.
> For example, you can connect a Qt progress bar to a Vtk pipeline.
> How far do we open the doors for other code in GUISupport/Qt?
> Right now, all that is in there is for putting a VTK window in a Qt widget.
> If we let this class in, then that pretty much opens the doors wide for 
> any other useful class.
> I'm not sure we want to do that.  Do we let this in, and say that only 
> "bridges" between Qt and VTK are allowed?  This vtkEventQtSlotConnect 
> class is a "bridge".  QVTKWidget can also be considered a bridge.

I would say this particular class can be let in because it specifically 
translates VTK observers into Qt slots.  This is equivalent to the 
existing support in the wrappers for Tcl, Python, and Java to translate 
observers into the wrapper-languages's callback.  Since there is 
precedent for this specific kind of class we can let it in without 
"opening the door" to non-bridge classes.

-Brad