[vtkusers] Using QVTKWidget with QT5 on Linux

[Ben Boeckel]

On Wed, May 06, 2015 at 16:45:39 -0400, David E DeMarle wrote:
> If you can share the right/wrong images, that would help diagnose the cause.
> 
> Is there opacity in the scene? If so depth peeling is needed to render the
> faces in the right order. To do depth peeling we need to ask the GPU what
> it can do and that can get messed up with different paths to the graphics
> context layers (under Qt vs natively for example.)

Do we not have tests for QVTKWidget? We do have Qt5 builders... Or are
the tests not comprehensive enough?

--Ben