Ray tracing with volume rendering


I am trying to render my wavefront obj files with netCDF. And I would like to apply the ray tracing to the obj files. But, when I applied the ray tracing with OptiX, the volume-rendered netCDF data disappeared:

Is it impossible to use OptiX with volume ray casting (or IndeX)?
Thank you.

Version : Paraview 5.8.0
CPU : AMD Ryzen Threadripper 2990WX 32-Core Processor

Afaik, not ray tracing backend in ParaView support volume rendering (yet).

Thank you for explanations. I look forward to the feature.

You can use OSPRay raycaster backend to visualize volumes. It is not possible with OSPRay pathtracer yet but we are working on it.

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I’m curious whether this is still the case. Or is it possible to use the OSPRay pathtracer for volume rendering nowadays?

is it possible to use the OSPRay pathtracer for volume rendering nowadays?

No, not yet.

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Just an update, it is possible with OSPRay path tracer since PV 5.9.


I just tried with pv 5.9 without success on a wavelet source. Am i missing something ?

Shouldn’t be anything tricky, just turn on ray tracing. Default is ospray ray caster, volume rendering there has worked since 5.2 or so. The difference in 5.9 is that when you change to ospray path tracer the volume rendering now appears where as up to 5.8 it disappeared as it wasn’t supported.

I’ll check too.

Works for me on Linux and Windows (and should on pre M1 macs). Note with path tracer speckling is worse, so you will want more samples per pixel.

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Indeed, it works !

Ospray pathtracer does not volume-render rectilinear grid data. So a ResampleToImage filter may be required.

OpenVKL does not yet have a rectilinear grid data type, so users have to either resample to image or convert to unstructured for scivis or pathtracer backends to volume render it.

Supporting it natively would entail adding rectgrid to OpenVKL and OSPRay and adding a vtkOSPRayRectGridMapper to VTK that maps VTK’s RectGrid mapper state to corresponding OSPRay API calls.