How to tell what version of OpenGL my VTK app is using & Apple's deprecation of OpenGL

Hi all,
How can I tell which version of OpenGL my VTK app is using? And is VTK performance on recent versions of OSX going to suffer now that Apple no longer supports OpenGL?
thank you in advance,

You can use the method ReportCapabilities on vtkRenderWindow.
Regarding OSX, there are some internal discussions but we are planning to continue support of this platform in the next VTK releases.

Thank you for your help, Michael. I tried to use the ReportCapabilities method as you suggested:

var OutStr=RenderWindow.ReportCapabilities();

And OutStr equals “no device context”. RenderWindow is an instance of vtkRenderWindow. What am I doing wrong?