Texture direction changing direction when rendered with Vray GPU and Backburner

[Anthonyyg]

I recently came across an issue where I submitted a job to the same computer using backburner. The first 89 frames of an animated conveyor belt rendered with the texture in one direction and from frame 90 onward it then rendered in a different direction.
Below I have attached the frames where it switches direction.


Its a Vray Material using a Vray Bitmap and UVWRandomiser with Stochastic Tiling.
I never noticed the issue when rendering with 3dsmax and nor were there any error messages. Has anybody come across this before?

Vray 5.10.02, 3dsmax 2021.3 Update and Backburner 2019 (2019.0.0.5)

[nikoleta.garkova]

Hi Anthonyyg,

Can you forward us the scene in question with all the assets so we can see if we can reproduce the issue? You can send it via our contact form, just make sure to mention this thread (or my name) in the email, thanks!

[mark_fonzen]

Hey Anthonyyg
Did you ever find a solution to this problem? I am running into the same issue with an animation I'm working on. I assumed the randomization would only be calculated once, but it randomizes the textures from frame to frame.

[Anthonyyg]

mark_fonzen no I didn't, I overcame the problem by rendering the troublesome item with regular VRay and comping in post. To be honest I have not revisited the scene but it looks like I should.