VRayVolumeGrid VDB Cache Distributed Rendering problem

[hotbox]

Hi,

I'm trying to DR a scene with a VrayVolumeGrid referencing a VDB cache on our file server.

The host and nodes are Windows 10

Running Maya 2018.1 and V-Ray 3.60.02

The cache reference is setup the same way all other files are in the scene e.g. file textures and alembic caches, using UNC.

I'm receiving the error:

[2017/Oct/17|16:17:42] warning: [PhoenixCachePlugin] You are using local machine Input path for distributed rendering:
[2017/Oct/17|16:17:42] warning: //IP.IP.IP.IP/PATH/FILENAME.0001.vdb
[2017/Oct/17|16:17:42] warning: [PhoenixCachePlugin] Please share the caches on a network location and adjust you Input path.

I've tried pointing the scene to the cache via network drive (as the host and all nodes have the network drives mapped), same error.

Just as a test I've tried copying the VDB cache to the C drive on the host and each node and pointing to scene to it locally, same error.

Does anyone know what I'm doing wrong?

The only thing that works is disabling DR, the host happily (albeit slowly!) renders the scene referencing the VDB cache on the file server via UNC.

Many thanks for any suggestions.

[Svetlin.Nikolov]

Hey,

Will look into this. This is a warning and not an error, so you should be able to continue safely. Do the caches render successfully?

The warning means that the VolumeGrid in DR mode needs to access the caches from a UNC path. Even if this is a mapped network drive, it will get recognized under Windows. However, I suspect that the reason for the warning is that the path starts with slashes and not backslashes. Will check the code and get back to you.

Cheers!

[hotbox]

Many thanks, is so slow testing without the farm!

The buckets from the nodes fail (render without the caches), the buckets from the host render fine.

I thought the flipped slashes might be it.

[Svetlin.Nikolov]

Hey,

So it was just the condition for the warning that needed fixing - slashes were automatically converted to forward ones for Linux compatibility and the check if this is a UNC path checked only for \\. Will fix this in the stable nightlies, however the VolumeGrid just prints the warning and continues, so there must be something else preventing the caches from rendering on remote machines. Your path setup sounds correct, and even setting just a local drive and copying the caches there should be able to render in case there were any sharing or user permission issues with the slaves...

Does any other geometry from the scene render? Also, are there any other messages from Phoenix in the log, no matter if they are errors, warnings or just info?

[hotbox]

Hi,

Yes, everything else in the scene renders fine.

I've just tested a Network Render using the same scene and nodes that fail on a Distributed Render.

The Network Render completes without a problem, no errors or warnings from Phoenix.

The only thing I spotted in the Network Render log was:

[2017/Oct/19|13:56:42] V-Ray: [PhoenixCachePlugin] Frame data 4028000 successfully loaded from //IP.IP.IP.IP/PATH/FILE.#.vdb.
[2017/Oct/19|13:56:42] V-Ray: [PhoenixSimPlugin] grid 67x75x53, cache index -2147483648.
[2017/Oct/19|13:56:42] V-Ray: Optimizing Volumetrics
[2017/Oct/19|13:56:42] V-Ray: (Estimated time remaining: 0h 0m 0.0s): 83 % completed
unsupported VDB file format (expected version 223 or earlier, got version 224)

I've just tested another Distributed Render, no additional errors, warnings, or info from Phoenix, apart from the one already noted above:

[2017/Oct/19|14:18:46] [PhoenixCachePlugin] Frame data 4028000 successfully loaded from //IP.IP.IP.IP/PATH/FILE.#.vdb.
[2017/Oct/19|14:18:46] [PhoenixSimPlugin] grid 67x75x53, cache index -2147483648.
[2017/Oct/19|14:18:46] warning: [PhoenixCachePlugin] You are using local machine Input path for distributed rendering:
[2017/Oct/19|14:18:46] warning: //IP.IP.IP.IP/PATH/FILE.#.vdb.
[2017/Oct/19|14:18:46] warning: [PhoenixCachePlugin] Please share the caches on a network location and adjust you Input path.
[2017/Oct/19|14:18:46] Optimizing Volumetrics: done [ 0h 0m 0.0s]
unsupported VDB file format (expected version 223 or earlier, got version 224)

Also, whilst here a question - how do I control which lights in the scene are linked to the VrayVolumeGrid? Currently all lights seem to be linked to the volume and as nothing for the VrayVolumeGrid shows in the relationship editor for light linking I don't seem to be able to specify?

Again many thanks for the help with this.

[sebbiej]

I'm getting this exact error with trying to render some Vray Openvdb clouds. I've got the clouds mapped to a network location, but when I try to render with DR on I get the following error message.
Also, nothing renders when I try to render a sequence via Backburner.

// Warning: V-Ray : //*****/Graphics/Graphics Dept/****/*****/*****/Maya/data/Flat_Clouds.0032/Flat_Clouds.0032.vdb //
// Warning: V-Ray : [PhoenixCachePlugin] Please share the caches on a network location and adjust you Input path. //

Would anybody know of a fix, please? We've got to get an animation rendering asap...

Windows 10 Professional, Vray 3.60.02.

Thanks

[hotbox]

The associated issue of VRayVolumeGrid not supporting light linking (not sure if it does now as Chaos advised it was on their to-do list but it didn't at the end of 2017) made VRayVolumeGrid unusable for me so I gave up with it.

Not sure where your VDB clouds are being generated (mine was smoke generated in Houdini) but in case it helps the way I got around this was:

1. Export a .bgeo.sc cache from Houdini.
2. Use the Houdini Engine to bring the .bgeo.sc cache into Maya as a Maya fluid (referencing the Houdini cache).
3. As referencing the Houdini cache with the Houdini Engine in Maya was very slow, cache out as a Maya fluid and import into a new Maya fluid object.

This allowed me to render the smoke as a Maya fluid with V-Ray.

Would have been a lot less hassle to use VRayVolumeGrid!

Best of luck with it.

[sebbiej]

The associated issue of VRayVolumeGrid not supporting light linking (not sure if it does now as Chaos advised it was on their to-do list but it didn't at the end of 2017) made VRayVolumeGrid unusable for me so I gave up with it.

Not sure where your VDB clouds are being generated (mine was smoke generated in Houdini) but in case it helps the way I got around this was:

1. Export a .bgeo.sc cache from Houdini.
2. Use the Houdini Engine to bring the .bgeo.sc cache into Maya as a Maya fluid (referencing the Houdini cache).
3. As referencing the Houdini cache with the Houdini Engine in Maya was very slow, cache out as a Maya fluid and import into a new Maya fluid object.

This allowed me to render the smoke as a Maya fluid with V-Ray.

Would have been a lot less hassle to use VRayVolumeGrid!

Best of luck with it.

Hey Hotbox,

For this, I'm using a library of OpenVBD clouds that I got from the following link. Unfortunately, we haven't got Houdini in our studio . Thanks for your response though!
I'm hoping to get my head around why the slaves can't find the cache files today, woo!

https://cubebrush.co/byvfx/products/...openvdb-clouds

Edit: I give up, this is impossible to fix.

[Svetlin.Nikolov]

The associated issue of VRayVolumeGrid not supporting light linking (not sure if it does now as Chaos advised it was on their to-do list but it didn't at the end of 2017) made VRayVolumeGrid unusable for me so I gave up with it.

Hey,

The light links of the VolumeGrid for Maya are already fixed in the V-Ray 3 stable nightlies.

AFAIK, Support are currently looking at the network cache loading issue and I have completely missed out on this issue since the forums's mail notifications are not always delivered and I apologize. Have you been able to get any hints on this? If you log onto one of the machines and render manually, do the caches load successfully?

Cheers!