Combine multiple AOV layers into one AOV layer

[mpowers]

AOV Material IDs.zipEdit: gave multiple AOV write RGB layers the same AOV name. Seems to work. Apparently using a utility node is also unnecessary, as shown in the tutorials. Attached is material file with "Material ID-001 <-12colors, on ID" and "Material IDs twelve separate AOVs" and a .json file to load AOV preset.

I want to combine multiple AOV write RGB layers to a single AOV layer. I don't need 12 separate channels in an EXR for Material IDs. (How about Arnold just makes a material ID output that can get at multi-material IDs - since cryptomatte can't)

Also, using AOV write RGB materials don't -show properly unless I use Activeshade. This is not a good workflow with super-high poly scenes with intricate normal maps.

[Christoph_Schaedl]

Have you tried Cryptomatte?

A i see you have. Sorry

[madsd]

What am I missing here? You say Cryptomatte can't do it.
Here I source 7 material ID's to a crypto_material AOV, working fine.

[mpowers]

Just wondering anyone from Arnold can address this:

Thanks Mads. However, this illustrates the problem I am running into:

1. Doesn't works if materials are assigned to separate objects using multi-material

2. Works if materials are individually assigned to separate objects

3. Doesn't works if materials are assigned to a single objects using multi-material

4. Doesn't works if materials are individually assigned to a single objects using material IDs

Crypto material: Crypto objects:

This is the MAX setup:Crypto element test.zip

@Mads Drøschler

[madsd]

So that would count 3 non standard unsupported direct ways.

For the 2 bottom ones, you can open a channel on the Data Channel modifier and set it to generate Element colors, you can do a custom AOV with those 2 and get some ID's going that way, you can generate an abitrary array of IDs for the 2 others as well in a rerun of AOV's.

You can also use crypto_asset to control it and use renaming of files tool to create flags that gets triggered.

You could argue you dont want to create custom AOVs, in case you should ping the devs and ask for the old material to be supported in crypto.