Mat ID limit 255 when using V-Ray RT ?? (no error when using ADV).

[JezUK]

I'm hitting problems with some Laubwerk tree models and as I've used these models before, I'm guessing it might be more to do with RT than ADV.

It seems to me that a lot of Laubwerk Tree materials have a Material ID of 1000 within their Multi/Sub-Object.

V-Ray RT is failing with an error message saying something along the lines of "there is a mat id in scene with a value higher than 999. (Maximum permissible 255)."

As I say, this doesn't happen in V-Ray ADV.

[vlado]

Do you have a scene for this?

Best regards,
Vlado

[JezUK]

Do you have a scene for this?

Best regards,
Vlado

Yes I do Vlado - but it's a really basic scene - I'm just playing with RT as I've recently upgraded my GPU cards as I want to use RT as much as possible as the speed differences are well worth it.

(you might well need Laubwerk - but I can collapse and send as Editable Poly).

Instead I've created a very simple scene with just a teapot and a plane - made the handle and spout have a Mat-ID of 1000 and the rest of the teapot a Mat-ID of 1.

Try rendering in RT and you will get an error message - render the same scene in ADV, no error message. Change Mat-ID to be less than 255, no error message in RT. I have a lot of Laubwerk Trees

Mat-ID-1000-not-supported-in-V-Ray-RT.zip

[theedge]

Yes, I also started noticing this with Laubwerk recently. It didn't happen before. So either Laubwerk changed their materials recently to use ID 1000, or something changed in Vray-RT and it does not support IDs above 255 anymore ?

[JezUK]

Yes, I also started noticing this with Laubwerk recently. It didn't happen before. So either Laubwerk changed their materials recently to use ID 1000, or something changed in Vray-RT and it does not support IDs above 255 anymore ?

It's nothing recent - my Laubwerk files are from existing (fairly old) libraries.

The reason I've noticed this is because I've started using RT.

In ADV you don't get this as being a problem.

So the first time I used RT with some Laubwerk files in, was when I first got this error.

Be nice if Chaosgroup sort this out

[dimension3plus]

I just bumped into the same problem. Only with Vray RT CUDA not CPU. The Multi-/Submaterial of the plant has only 19 ids, but the last one ist number 1000 - that's the culprit. I'm going to try updating the laubwerk plugin, maybe it'll help.
Have you solved the problem or found a workaround?


Update: even with version 1.0.24 the problem is still there

[theedge]

No haven't found a solution. Actually I stopped using RT Cuda. Too many annoyng small things like this one. I just can't loose time with that. Back to 100% CPU and I'm very happy.
I suppose GPU rendering is perfectly fine for certain projects where all the aspects of the scene are easily manageable. But for heavy archviz scenes with assets coming from different sources and multiple plugins used there is just no way to use GPU condifdently.

[JezUK]

No haven't found a solution. Actually I stopped using RT Cuda. Too many annoyng small things like this one. I just can't loose time with that. Back to 100% CPU and I'm very happy.
I suppose GPU rendering is perfectly fine for certain projects where all the aspects of the scene are easily manageable. But for heavy archviz scenes with assets coming from different sources and multiple plugins used there is just no way to use GPU condifdently.

I agree with you 100%, but when you get the opportunity, do try it - I was blown away by the performance benefits.

[theedge]

Yes I know. I have several GTX 1080, two in my main workstation, and there is no doubt that the raw performance of GPU is amazing.
Also I'm not blaming V-Ray here. Those archviz scenes can be such a mess sometimes... It's just that I can throw them at Vray CPU and I know that most of the time it will be Ok.
If I had a more robust workflow (check all bought 3d models before using them, correct them, verify/rebuild/update old materials, only use plugins 100% compatible with GPU, ...) I'd certainly use the GPU render.