vtkRenderWindow: adding stereo mode `emulate`
Adding a new stereo mode VTK_STEREO_EMULATE
which is stereo without
creating stereo buffers or doing any special composing of the two eye
images at the end of stereo rendering. This is useful to support
ParaView remote rendering use-case where the client needs stereo. With
this mode, we can support setups where the server doesn't support active
stereo, only the client does.
Helps support paraview/paraview#18996 (closed)
Edited by Utkarsh Ayachit