Hello,
I have a question about the vtkOSPRayVolumeMapper. I would like to know whether the vtkVolumeMapper::MAXIMUM_INTENSITY_BLEND is supported.
If the mapper does not support this blend mode, I should know how to make it support.
So. could you please advise for me?
Thank you. 
Cc: @Dave_DeMarle
mIP and MIP are not supported by the vtkOSPRayVolumeMapper.
I anticipate that adding it would require minor changes to the VTK level to pass the state down to OSPRay but modertely intensive changes at the OSPRay level and perhaps OpenVKL levels for the sampling.
Specifically one would need to add a new volume sampling code path that is swapped into place here ospray/modules/cpu/render/scivis/volumes.ispc at master · ospray/ospray · GitHub
Then, in that code path I recommend adapting OpenVKL’s range iterator API to find the maximum value along each ray quickly.
Feel free to start a discussion on the OSPRay github project (linked to this one) when you need more details.