Alembic in Proxy

[christian_schneider1]

We encountered the problem - maybe a bug - that we cant use Alembic files in V-Ray Proxy objects if they are not stored locally. Seems to be a link problem.

[deyan.hadzhiev]

Hi christian_schneider1, can you share a bit more details on your setup? Are the alembic files on a shared server, or you are trying to use them when rendering via Distributed Rendering? Can you share the exact path used in the Proxy objects? What versions of V-Ray and Cinema 4D are you using?

[christian_schneider1]

The V-Ray Log error message is "Could not load mesh files) Error : -2 path is empty (could copy the text seems to be forbidden)
The Server is a shared server mounted as Z. The alembic doesnt show at all unless the path is local.
Setup is V-Ray 6.20.02, C4D 2024.4.0, Windows 11 machine Intel i9-13900k, 2xRTX 4090, 64gbs of Ram

Locally I can render the alembic in proxy - and see it depending how the scene was structured before creating the .abc file.

[zhanet.georgieva]

Hello christian_schneider1,

We couldn't replicate the issue. To investigate further, could you provide some details:

• Which platform were the alembic files originally exported from?
• Are you encountering problems with other assets (like textures) from the same shared server?
• Are the paths used when loading the .abc files relative paths?
• Does the issue persist when loading .vrmesh files in the V-Ray Proxy ?
• Are you using Distributed Rendering?
• Please share the complete log file for further analysis.

Thank you.

[christian_schneider1]

Sure thing zhanet.georgieva,

• Which platform were the alembic files originally exported from?

I exported the alembic f-i-l-e [Why do I get a Error 403 if I try to write file after alembic?? ] (single file) from Cinema4D after creating a mesh volume (openVDBmesher) from particles using X-Particles.

• Are you encountering problems with other assets (like textures) from the same shared server?

No I dont encounter any problems with other assets from the shared server.

• Are the paths used when loading the .abc files relative paths?

No I have been using absolute file paths.

• Does the issue persist when loading .vrmesh files in the V-Ray Proxy ?

No the issue does not persist when loading .vrmesh files - we store all chaos cloud files on the shared server too.

• Are you using Distributed Rendering?

I intend to use distributed rendering but did not when encountering the error.

• Please share the complete log file for further analysis.

Sure -
[14:52:49.744] V-Ray Frame Buffer message log initialized

[14:54:18.665] Bitmap manager created.

[14:54:18.672] Setting number of rendering threads to 31.

[14:54:18.672] GI engines: 'Brute force' and 'Brute force'

[14:54:18.672] Reducing shading rate from 6 to 2 for interactive rendering

[14:54:18.673] Preparing renderer...

[14:54:19.042] Using per-pixel filtering for IPR.

[14:54:19.045] Preparing scene for rendering... (0.0%)

[14:54:19.045] Tiled texture cache set to 4096 MB

[14:54:19.046] Preparing scene for rendering... (finished in [0h 0m 0.0s]) (100.0%)

[14:54:19.046] Light tree is enabled with clamp coefficient 0.1 and even split coefficient 1.

[14:54:19.055] Using lowest thread priority.

[14:54:19.489] Max ray intensity is enabled: rendered result may have incorrect brightness.

[14:54:19.490] Consistent lighting elements are enabled.

[14:54:19.490] Disabling info and debug messages for IPR.

[14:54:19.490] Log dump enabled for warnings and errors only

[14:54:19.494] Warning : Could not load mesh files "Z:\04 Transfer\Test\FlowFluidSim\a-l-e-m-b-i-c\Fluid2.abc"! [IT Word for problem {Thanks again for Error403}]: "[AlembicMeshFile::init()] -2: File "Z:\04 Transfer\Test\FlowFluidSim\alembic\Fluid2.abc" is empty!"

[zhanet.georgieva]

Hey christian_schneider1, can you share the alembic file?

[christian_schneider1]

Yes zhanet.georgieva.

You can get it via wetransfer here.

[zhanet.georgieva]

Hello christian_schneider1,

I have tested you alembic file, but again I was not able to reproduce the issue.

Could you provide some additional details:

• Could you please provide more information about your shared server? What kind of shared server you are using?
• I noticed from the log that the alembic path is different from the path that Cinema 4D is looking for. In the first path, the folder is named "a-l-e-m-b-i-c", while in the second path, the folder is named simply "alembic" without any dashes. Could you test by copying the fie to a folder without dashes or any other special characters and see if you can load it from there?
  [14:54:19.494] Warning : Could not load mesh files "Z:\04 Transfer\Test\FlowFluidSim\a-l-e-m-b-i-c\Fluid2.abc"! [IT Word for problem {Thanks again for Error403}]: "[AlembicMeshFile::init()] -2: File "Z:\04 Transfer\Test\FlowFluidSim\alembic\Fluid2.abc" is empty!"
• I also noticed that your shared server is mapped. Could you test by accessing the shared server without it being mapped?
• And finally, do you experience this problem if you open the alembic file directly in Cinema 4D, not by loading it from the V-Ray Proxy object?

[christian_schneider1]

• Could you please provide more information about your shared server? What kind of shared server you are using?

The server we use is a synology server with multiple drives.

I noticed from the log that the alembic path is different from the path that Cinema 4D is looking for. In the first path, the folder is named "a-l-e-m-b-i-c", while in the second path, the folder is named simply "alembic" without any dashes. Could you test by copying the fie to a folder without dashes or any other special characters and see if you can load it from there?

The a-l-e-m-b-i-c thing was done manually because I was searching for what caused the Error403 stopping me from posting an answer.

YES, when using a path without special characters it seems to work.

• I also noticed that your shared server is mapped. Could you test by accessing the shared server without it being mapped?

Changing to a non-mapped access didnt do anything in addition.

• And finally, do you experience this problem if you open the alembic file directly in Cinema 4D, not by loading it from the V-Ray Proxy object?

When loading directly it works just fine.



Thanks for finding the issue zhanet.georgieva

Additional question - Is it the expected bahavior that the alembic is not displayed in the c4d preview when using an alembic in v-ray proxy?

[zhanet.georgieva]

Hi christian_schneider1, Typically when you load an alembic file through V-Ray Proxy, it should be displayed in the viewport. If you're encountering issues with the visibility of an alembic, it may be related to the specific file itself, and the problem could be connected to its export.