Merge topic 'doc-opengl'

b61cc84a Apply 1 suggestion(s) to 1 file(s)
7676b6ac Document FrameBlitMode in vtkOpenGLRenderWindow.

Acked-by: Kitware Robot <kwrobot@kitware.com>
Tested-by: buildbot <buildbot@kitware.com>
Reviewed-by: Jaswant Panchumarti <jaswant.panchumarti@kitware.com>
Merge-request: !10341