Arnold does not render use Material IDs on TyFlow particles

[Anonymous]

I'm reposting this from the TyFlow forum since the developer states that this problem lies on Arnold's end.

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I've got an object that has been voronoi fractured and set so that the chunks that intersect with the beam objects are deleted. The RGB-Y coloration is for testing. The red material is supposed to be a painted hull material, green would be bare metal, and blue would be a molten metal material.

The material IDs appear to be applied correctly in viewport, but when rendering using Arnold, all tyflow particles render as Yellow, which I used to represent 'error.'

Are there any fixes for this error at the moment?

[madsd · Accepted solution]

I wrote a replacement for Object, Material and Element Id for all the particle engines in max.
It is a different more agile approach, and also works with Tyflow.
You can see here I have material Ids working and ready to be shaded.

It requires the source geo to be parsed through a process in DCM modifer to generate the Material Id and the element ID ( all engines already parse a retrivale object ID )
then collapse to editpoly and parsed into tyflow, then my shader can pick up and gain full control over the assets that may be living in tyflow.

This is a custom tailored solution, not stock by any means.

Im just showing you that Arnold works with Material Ids in tyflow, but I also understand you have issues using out of the box tools, more specifically the multisub material.
I would open an error report in that case.

But if you could, perhaps upload a .zip file with a plane and some teapots with some material Ids on so we can see how you wire it all together and expect it should be working with your particular setup.

[Anonymous]

Hi, how would I submit an error report? As for the scene, could I just send the test scene I created that is being shown in the pictures?

[madsd]

yes, you can upload it somewhere if its over 2mb. and past link to the zip.
then we can take a look.

[madsd]

You can also attach it to the tyflow forum, I am monitoring your original thread.

[Anonymous]

Quick update: I was led to a solution that works 'out of the box.' I just had to use TyMesher on the TyFlow particles.

[madsd]

Great.

Although that can potentially be expensive memory wise, if you are working with very large constructs. But if it works in your particular case then that wont be an issue.

[patrick.proier]

I had the exact same problem today! Its very frustrating/irritatung because I see the Multi/Sub Material correctly in the Viewport but the rendering is different/wrong 😕 ...Any chance to fix that problem? ...or any idea for an easy/fast workaround?

thx,

Patrick

[patrick.proier]

I will try that as well 🙂 ...but it would be great if the team can fix that issue with Tyflow.

[jeff.mcguigan]

Are there any plans to fix this issue in the next release of Arnold?

[madsd]

The bug has gotten a ticket and is being looked into.
So you will need to wait until a fix surfaces in a future build.

[tyroneA4DMP]

Tycache seems to help