volume grids shaking

[ttdww]

I'm working for a client with a large farm running vray 3.6. We're having some vray volume-grid wiggling/shaking after reviewing farm renders. Like they are slightly jumping in position. On a single node, the frames are smooth with no shaking. The farm is running Vray 3.6, caches are running at speed 1.0, index 0, interpolation nearest. The volume grid's have been scaled down to fairly small, like 2% of original size. Is this a known issue and how to fix? Thank you!

[georgi.zhekov]

Hello,

We have seen such an issue where vdb's coming from FumeFX were jittering when loaded in VolumeGrid.

If they are coming from an old version of FumeFX - there the transform of the vdbs was bugged so the only option is to resimulate them with a newer version of FumeFX.

If the files are not from Fume can you send over the scene so we can take a look?

[ttdww]

Hi,
The fumefx version was 4.x, however the shaking is like the entire volume grid moves up/down, side to side on various render nodes. They decided to try a few farm nodes updated to Vray 3.7 and the problem went away, so will hope for more nodes to be updated. Does that seem to match up with any bugs fixed in Vray or Volume Grid? They are primarily on 3.6.05 if I recall. Thanks!

I also noticed that since the upgrade from 3.6 to 3.7 (on my login box for editing) all the Volgrids have moved out of their place and rotated so I'm having to reposition them all. Any tips on an easier workaround would be great. Thx again!

[georgi.zhekov]

Indeed it should be working in 3.7 so if it's an option we recommend to upgrade to it.

As for the offset - FumeFX have fixed a bug in their caches transformations between FFX4 and FF5, but they have not updated the version info in the cache files so we cannot differentiate between 4 and 5. FFX5 now exports correct transforms and the VolumeGrid uses this model of transformation.
Unfortunately we don't have an easy way for repositioning those files.