LC calc infinitely stuck when using animated vrayproxies through forest pack with mb

[mori4h]

Hi,
When using animated alembics via vrayproxy and scattered via forest pack (animation mode, follow geo, or random samples) and when using LC as secondary GI, with motion blur on, there's an infinite LC calculation, basically it doesn't go through the first samples pass.
After 2 days trying to debug, i found out that if i import the abc via 3dsmax, there's no issue when rendering. So i assume it's a vrayproxy problem. Not only that but using vrmesh it's a complete pain (ultra slow to export, fails constantly in the render farm due to faulty voxels bug, etc).
Since we do a lot of environments that require animation, this is a huge issue.
In the past this issue was present but then fixed a few years ago, now it seems to be back. I tried several FP versions and several Vray versions, all on 2024. The bug persists.
So right now im in the process of manually converting dozens of abcs instead of vrayproxy to deliver a project.

I feel like VrayProxy (and vrmesh) reallllllyyyy need to be upgraded. It has been super slow for several years and 99% of the bugs we find it's due to it. But since it's an integral part of our workflow, we have to somehow live with it.

[vladimir_krastev]

Hi, thanks for posting. I tried this setup on a 3ds Max 2024 with V-Ray 6.2 but I found no issues.
Please find attached my test scene. Could you review it to make sure I am following your steps?
You could also test render it on your workstation to compare the results.
If this simple scene works for you then please send us your scene that has the issue.
You can do that here or trough the support contact form. If you go to the contact form please include a link to this thread in your message for better tracking.

[mori4h]

Your scene crashes 3dsmax (not even LC infinite stuck) as soon as you add VrayCam > turn on motion blur > LC retrace 8 > bucket sampler. I tried FP follow geo and random samples in animation tab. Same outcome.
Can you confirm?

[mori4h]

I uploaded a cleaned up scene via the support contact form. Here's the id - 213798

Here's a clip of what is happening too. https://streamable.com/h732yr

(i can't upload files or mp4 in this forum for some reason..)

[vladimir_krastev]

Hi, thanks for the scene I will look into it.

Your scene crashes 3dsmax

Yes you are correct. I forgot to enable motion blur with my previous test.

[vladimir_krastev]

The issue is reported under VMAX-14006 for developers review.

[mori4h]

Thank you. Please let us know when you find a fix, even if it's in a nightly.

[mori4h]

Hello,

Has this been fixed? There hasn't been nightlies since March, and even in the latest stable the bug persists. We had the same issue in 2 projects right now, we had to basically take out the animation.

[vladimir_krastev]

Hi, after careful investigation and collaboration with the Forest Pack developers the issue is in iToo hands now. The fix will be available with a future release of Forest Pak. I now tested the 8,2,6 version but the crash is still reproducing. Testing with V-Ray 6.20,06 and 3ds Max 2024.2.