How to create Object based AOV rgb matte pass?

[mattgfx7]

How can I create an Object based AOV rgb matte pass? I'd like to do it similar to how VRay works by assigning object ID's, not using materials. Is this possible? I can only seem to find ways to do this by using materials but what if two objects have different materials but I want them as the same matte?

Thanks!

[Stephen.Blair]

Did you take a look at cryptomatte?

https://github.com/anderslanglands/alShaders2/releases

[mattgfx7]

Hello, I understand there are other solutions like object ID pass with tons of different colors and cryptomatte but I'm looking for a more standard method of an object rgb pass.

[Stephen.Blair]

Assign ids to objects as user data, and use that user data to drive the matte colors.

[cdordelly09]

You can use the Arnold Custom AOVs tag with only 3 materials to assign different rgb ids. i.e:
Beauty:

ID group 01:

ID group 02:

rgb-ids-aov.zip

[mattgfx7]

@Stephen Blair

How might I do this in Maya? I can't seem to find documentation on how to do this?

[mattgfx7]

@Carlos Dordelly

Can I do this in Maya?

[juampavaren]

do you have some option:

1. Create a Custom AOV in render setting windows in AOV shelf
2. Create a Cryptomate node and attach crypto material and Cribto Object in AOV shelf
3. Create custom collection in render setup windows
4. Create a render layer with multiples shaders

[cdordelly09]

I'll ask to a friend how to do this in maya because I only know the Maya basics. Maybe you can find this option in the arnold attributes tab of each object?

[rendermen]

@Matthew Gleason
http://kiryha.blogspot.com/2014/02/render-notes.html

But better try to get how to use Cryptomate!

[cdordelly09]

Yes, Cryptomatte is really useful.

[mattgfx7]

It just seems crazy Arnold doesn't do this by default...