Hi!!

I'm doing a pyro simulation I wanted to render with arnold and I'm having problems exporting the sim to vdb.

I've made different test and it is curious. If I do a simple sim using “Billowy smoke” of houdini shell and I export it to vdb it works perfect. But when I use “explosion” from the shell, when I write the sim in vdb it looks pretty different and make my sim looks awful.

Can anyone tell me what I'm doing wrong??

Thanks!

a scene file will help us to analyze your problem…

What you are seeing by loading back in the .vdb volumes are all the volumes displayed in the viewport with all visibility masks defaulting to visible. If you look at the DOP IO import_pyrofields SOP each field is assigned a visibility property: Smoke, Rainbow, Isosurface, …, invisible. Most are set invisible with Pyro field imports.

When you save out .vdb files they do not contain the visibility mask along with other Houdini specific primitive properties that are saved if you were to generate bgeo's.

The renders should be just fine either way.

If you want, you can append two Primitive SOPs. The first to set all the volume visibility fields to invisible. Then append another Primitive SOP, in the group field match all the fields as visible in the top DOP IO SOP and then set the visibility to smoke.

You can also put down a Volume Visualization SOP but that is for viewing multiple volumes as a viewport composite operation.

also the visibility SOP does the trick