querying opengl extensions causes a window to popup and go away
This issue was created automatically from an original Mantis Issue. Further discussion may take place here.
When running some pqClientClipUndo or maybe other tests, I notice a flash of a window coming and disappearing. Turns out that it comes from vtkPVOpenGLExtensionsInformation::CopyFromObject, which creates a render window and destroys it.
There should be a window coming up like that. Perhaps adding a hide/show to vtkRenderWindow? Set it hidden after creating it. Then when opengl extensions are queried, it won't show the window (call XMapWindow or whatever for the platform). Does there really need to be a vtkRenderWindow::Render to query extensions? Just creating the context should be enough, or maybe just associating the context with the window is enough, right?