Hi there,

I am trying to produce a velocity attribute from a volume sequence that was produced in CFD software and converted to .vdb (not converted by me) in order to render with motion blur.

I've tried a few things, including convertvdb to polygons and then using the trail node to compute velocity based on the geometry. However this doesn't work because the volume is re-meshed every frame and the polygons end up in totally different positions each frame. resulting in this mess when I visualise the ‘v’ attribute.


I just wondered if any one knows if it is possible to produce a velocity attribute when the volume itself doesn't carry anything other than its voxel values?

I'd be very grateful if you could help, thanks.

You could give volume optical flow a shot. I'm not sure if it works with levelsets though.

Thanks for the advice. I did give optical flow a go but without any luck. I'll persevere and give it another go.