Weird streaky Issue

​Hello. I’m facing a weird issue after updating to vray 6.

It’s a little hard to describe but it sometimes happens when rendering. When the issue has occurred the only solution is to shut down Maya and open again.
The issue is not scene specific.

It must be a bug, but rendering a lot of animations out over night it’s a huge problem to have to rerender half of them because of this issue.

Anybody having the same issue?

Here are some examples.

You could be reaching the ram limit. Are you using chaos scatter if so are you using local ray server? I see motion blur in your render, you could try without it. I’m almost positive its a memory issue.

Thank you for the reply, but I don’t that is it. An error in MB was also my first thought but there is no MB.

Here’s another example. No fog, no MB and no dof. Just a turntable.

I think it has something to do with geometry. You can see that some objects are moved around the scene as well. Looks like exploded view or something. The geo is not supposed to do that.

Also this specific scene only uses around 10GB of memory. The issue is happening on multiple machines on our farm. In Maya 2023 and 2024. Vray 6 update 1.

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Looks like in this case you are using vray cutter? It could be a different issue. However can you post a part of this scene so we can investigate. Likely you can send this to support as well. I’ve been having similar issues, not exactly like this but in some complex scenarios the model would randomly flip or explode in pieces. I think it was due to how we rigged it though.

I’m somewhat glad that others have experienced this issue as well. Yes there is a clipper in this specific scene but it happens in other scenes that doesn’t have a clipper as well.

That is what we experience as well with a look that resemble an exploded view. But then the next rendered frame is all streaks.

I’m not able to share the scene unfortunatly, but I’ve written Chaos Group and asked for support, also referencing this post. Hopefully they will comment or reply soon.

We are running into the same thing, it has shown up on multiple unrelated projects now. We’ve had to roll back to the release prior to V-Ray 6 update 1 to complete renders, otherwise we would come back the next day to find half of our frames messed up.
I believe it’s some kind of scene translation issue related to update 1.

  • It happens to light and heavy scenes alike.
  • It happens on seemingly random nodes.
  • Once a node begins rendering bad frames it seems to continue rendering bad frames, until Maya or the batch process is restarted. The bad frames finish faster than the good ones so the ratio of bad to good frames quickly becomes skewed.
  • We get the crazy streaky renders that look like a motion blurred mess (as shown in Twist’s first post), or we get models exploding in strange orientations (as shown in Twist’s second post).

Yeah we have same behavior also. If a few machines go “bad” they will render all frames bad and either shorter render time, or similar but will write black frames. Separately on other jobs, parts of the model will explode. Hopefully this can be fixed.

This issue is a huge problem. And it needs to be fixed ASAP!

@Twist In your video it looks like the camera transform is broken. Maybe it’s a general transform problem that happens randomly.

We haven’t managed to reproduce it on our side yet. Any chance you can send us the logs from a failed frame and a correct one?
Also, can you share your exact OS, Maya and V-Ray versions?

Yes i Can share that with directly via a private message.

Could you send the logs via e-mail? mihail.djurev @ chaos.com and CC to support @ chaos.com to start a support ticket as well.
Just reference this thread and please add the detailed version information as well.

Send you an email now. There is already a support ticket on the issue

This issue should be fixed in the latest stable 6.1 nightlies. Build 32256 from September 12th contains the fix.

The fix will be included in the upcoming hotfix as well.

For anyone interested. A hotfix is coming soon , customer support have told me.

Any info on what it related to?

I think it’s something to do with geometry compiling

Indeed it is, I have been talking with the devs about it. They have recommended to use this environment variable for the builds prior to the one which has the fix which solved our issues.

Same here, but they also said not to share this env var publicly since it slows down rendering. But yes, its a temp fix until a hotfix is released

Oh shoot I didn’t know this. I’ve edited it out.

There is a fix available in the latest stable builds and it will be included in an upcoming hotfix too.
You can get a build here: Chaos