Software:
Maya 2018 | V-Ray 3.6
To Activate Viewport IPR with V-Ray for Maya:
In the Viewport menu,
Under Renderer, choose V-Ray IPR
Software:
Maya 2018 | V-Ray 3.6
To Activate Viewport IPR with V-Ray for Maya:
In the Viewport menu,
Under Renderer, choose V-Ray IPR