Hello,
I was recently experimenting with the vtkOSPRayVolumeMapper with a vtkImage dataset and it appears that clipping planes (i.e., added with mapper->AddClippingPlane(myPlane)) are not respected / supported. Rather, the full volume is always rendered regardless of the presence of any added clipping planes. I found this issue on the Ospray repository, which leads me to believe that it’s a current limitation of the Ospray renderer, but I wanted to check in to make sure that this wasn’t an issue introduced from the VTK side. I’m using VTK 8.2.0 with Ospray 1.8.5. and can include a minimal example if necessary.