I have 62 time steps of a simulation of an expanding nebula as Fog VDBs where the fog represents element densities.
I want to "morph" between all of them over a number of frames.
My current strategy is to animate the mix between the first 2 VDBs using a VDB reshape SOP.
Then I switch from that node to the next pair of the same setup.
However, this would be very labor intensive having to set it up for 62 steps.
Alternatively, I'm experimenting with the VDB morph SOP, to make it look more like a natural evolution, instead of "just" a cross dissolve.
Either way, it would require wiring up multiples of 62 nodes.
I was thinking of writing a python script to semi-automate the setup, but wanted to reach out in case I'm overlooking something.
Thanks

You'll be delighted to hear that both Blendshape SOP and Sequence Blend SOP can handle vdbs these days. Just plug them in, select your preferred voxel blend method and blend away.

protozoan
You'll be delighted to hear that both Blendshape SOP and Sequence Blend SOP can handle vdbs these days. Just plug them in, select your preferred voxel blend method and blend away.

Hi Martin,
excellent! I'll give that a try.
Many thanks.

Hi Martin,
the Sequence Blend SOP Voxel Blend support looks very promising!
However, wiring 62 read nodes into the blend sop is very manual.
Do you, or anyone reading this thread, know a more procedural way to wire up a file sequence into a sequence blend sop?
Thanks

If "artistic" control is not needed (like, blend at very specific times), and/or you have a lot of input and just want to blend the whole thing through, you may try the Retime SOP (which also does volumes and vdbs these days).

protozoan
If "artistic" control is not needed (like, blend at very specific times), and/or you have a lot of input and just want to blend the whole thing through, you may try the Retime SOP (which also does volumes and vdbs these days).

Hi Martin,
the Retime SOP looks promising after a preliminary test.
I noticed that Retime/TimeWarp has similar functionality.
The data time steps are non-uniform, so I'm going to try creating a curve in the TimeWarp Input Timestep field with keyframes representing the intervals.
Thanks