OpenVDB to renderman

[DeonOosthuizen]

Hi

Our studio works intensively with Renderman 20.9 and Maya 2016 and we've been testing OpenVDB examples and we get them to work.
But when we export any .vdb from fumeFX 4.x and bringing it back in we either get a small foggy cube or Maya crashes.

Has anyone gotten FumeFX .vdb working in RenderMan and how do I go about in getting it to work correctly?

Kind Regards
Deon Oosthuizen

[sitnisati]

Hello,

I'm affraid that you'll have to contact Renderman developers so they can see why Renderman crashes.

Regards,
Kresimir Tkalcec

[DeonOosthuizen]

Thanks we got it partially working.
What I need to know is when we view the grids that fumeFX writes to the .vdb cache it makes a Smoke grid and a Flags grid.
what is the Flags grid used for?

Deon

[josip]

Hi Deon,
Flags grid contains information what occupies each voxel (e.g. source, or collision object).

Regards,
Josip

[DeonOosthuizen]

Thanks

Is there a way to cache out the .vdb to not include the Flags grids but to only give me smoke, firefuel and temperature

[josip]

Flags grid cannot be excluded, but as far as I know, applications which use OpenVDB do not include channels they don't use. Also, Flags grid occupies very small amount of space compared to other grids. Is there any problem with RenderMan and Flags grid?
Other fields can be excluded in post processing.

Regards,
Josip Šumečki

[DeonOosthuizen]

when building the shader to render the fume cache I use the Smoke Grid, FireFuel Grid and Temperature Grid and only Flags Grid is left unused

when submitting a render we get dis error

// Error: (07/20 08:35) rfm Error: X00002 Plugin error: impl_openvdb: Grid "Flags" in file "/dev/sandbox/sandbox_doosthuizen/FumeFXVDB/FireBall.0100.vdb" is not of correct type

All the grids are float value grids and only flags shows up as a int32 grid so
I'm trying to lessen the amount of errors that I sent trough to our farm as it will reject a job with a sirtuin amount of errors

[josip]

Thank you very much for this info.

I will try investigate this issue. There is a possibility that RenderMan uses some old version of OpenVDB library which doesn't support int32 fields.

Regards,
Josip Sumecki