rendering: Hoist PhysicalToWorld api from VR to base class
Moves PhysicalToWorld
matrix and friends from the vtkVRRenderWindow
class up to vtkRenderWindow
so it can be available in CAVE environments. Adds a test to indicate how an interactor can move it's viewpoint through a scene of objects, and those in world coordinates will fly past, while those in physical coordinates remain in their original positions.