I’ve made a smoke simulation using fluid in physics properties (mantaflow). I want to export it so that I can duplicate that movement of smoke, change the orientation slightly and merge them together.
But I don’t understand how to export the simulation. I’ve tried to export abc but that exports the object and not the smoke simulation.
If your Format Volume is set to OpenVDB, then your cache is your export; a sequence of VDB files.
Copy that file sequence to another folder to save it, and import through SHIFT-A/Volume/Import OpenVDB.
You don’t need to export anything. Just make sure you baked in the .vdb format, then go into the cache folder. There, you will find your .vdb sequence. Simply move it into an other folder to keep it, then you can import it as a volume object back into Blender or into an other software that supports it.
Just be aware that there is a bug in Cycles at the moment: if you import multiple .vdb volume objects and give them different scale values, they will have square visual glitches if they touch (at least they did last time I checked).
This worked beautifully! Thank you.
A follow-up question, I definitely baked the data in VDB format. And I baked the noise as well, also stored as VDB. However, in the cache, the noise and the fluid data are separate. And when I imported both of them, the noise is not influencing the smoke anymore. How can I ensure that both smoke and noise influence are imported together?
I just tested it and here is what I had to do to make it work.
1- Import only the noise data, it’s a full .vdb sequence in itself with the full smoke+noise.
2- If you go in the volume object settings, you will see that the noise sequence has attributes that are named differently from the regular simulation (ex. instead of “density”, there is “density_noise”). You have to use those attributes in the material instead of the regular ones.
All you need to know
While baking, I had adaptive domain turned on and that resulted in a very beautiful render in the original file (here is the render) but when I import the same vdb into a new file, it trembles (here is the trembling version).
I turned off the adaptive domain that solved the trembling problem, but the output itself changed. It doesn’t have the same look & feel anymore. Here is a render image:
Any ideas on why this is? And how I can achieve the original effect without trembling?
My first guess might be an FSP mis-match. Is your new file running at the same FPS as the one that generated the VDB sequence?
Hi. The adaptive domain lets you simulate with much more efficiency, it adapts a boundary domain just where is fluid. Also, there is an issue with the .vdb saving when adaptive domain is enabled. In fact, Mantaflow still uses .uni format in Mantaflow. Until there is active development in Mantaflow, it will not be possible to simulate.
this video will show you everything you need to know including how to add back the noise in your VDBs
