Looping animation with Alembic and VrayProxy

[jgriffin]

Here's a fun one. When I read in an animated alembic with vrayproxy, the vrayproxy is holding the animation for one extra frame before looping to the first frame.

Quicktime here: https://www.dropbox.com/s/8336tgw281...dness.mov?dl=0

To add to the weirdness, if I read in the exact same alembic cache with Maya's native tool, it cuts off the very last frame and loops to the first frame.

Where this gets particularly frustrating is when I cache a mesh and its XGen fur to alembic (separate caches) and then read those in with vrayProxy, the vrayProxy will hold an extra frame on the mesh cache but not on the Xgen cache.

Quicktime here: https://www.dropbox.com/s/jazo6pv2ls...hXGen.mov?dl=0

I'd like to stick with vrayProxy for my XGen caches as they are quite large and the Maya alembic importer crashes nearly every time I've tried to use it.

Any ideas on how to eliminate that held frame? I've tried the "Sequence Override" settings and they have no effect. I've attached a scene file with caches if anyone wants to take a peek.

Thanks!


AlembicWeirdness.zip

[tashko.zashev]

Hi,

I can confirm that this is not the correct behavior for Alembic files loaded via Proxy node and the issue is now logged as a bug in our system. Looking for a workaround the loop goes fine with vrmesh file conversion. Can you try this until we are ready with the fix ?

[jgriffin]

Thanks Tashko! Converting to vrmesh with ply2vrmesh still exhibited the hold-frame problem, but creating the vrmesh directly from Maya loops properly. And that gives me consistent behavior for mesh and xgen caches which is what I need. Thanks!

[tashko.zashev]

Actually this is exactly what I tried. Proxy generated from the Maya loops. Haven't tried the ABC to Vrmesh conversion, but good to know that it doesn't work.

[scorpes]

Is this bug already fixed? Got the same problem...
If I import a alembic as a proxy, the framerange for the alembic is 62-134, when I look into the VrayMesh file info (on the proxy shape node) it says the animation is 135 frames which is wrong (should be 73). I want to use the proxy as loop and the animation is standing still for the first 62 frames... is it possible to fix this?

[jgriffin]

I did a quick test and am seeing the same thing even when manually setting start offset, sequence start and sequence length. Caching out frames 62-134 as Vray proxy results in proper looping of frames 62-134. So a work-around may be import your cache using Maya's native Alembic importer, offsetting the animation and then re-caching to vray proxy.

[scorpes]

Yes that's what I did now, but the alembic proxy workflow is way faster (caching). Would be nice if this can be fixed.

[yolov]

Point taken. I'll make a note to look into this.