[HOU-2785] Issue with aovs added in the material builder

[Hannes Drossel]

Hi!

We found an issue with custom aovs that we are adding inside the material builder. When having the same aov name in more than one shader they are added to each other.


here is how its set up. Emissive material for the beauty. And same texture in the aov slot on the vrayOutput



RGB channel



AOV1 channel


This is kind of urgent for us to get fixed.

Thank you in advance!

"vrayHoudiniVersion": ["51020", "18c8f5e"],

/Hannes

[Gosho.Genchev]

Hey Hannes Drossel ,

Some of the images are not loading but from the description, I can understand the query.

When having the same aov namein more than one shader they are added to each other.

This is actually the expected behavior - if you have textures from different materials going to the same AOV, they'll be added one over the other. I have an idea how we can go about improving things - I'll ping you with more info later today.

Best regards!

[Hannes Drossel]

Hi Gosho.Genchev !
I think it was not like this before though. At least not in vray4.

What is an issue for us is that we are adding those extra aovs in the lookdev assets. Then when we have multiple instances of that asset the values of the aov changes.
So having one instance of it it look as we want. Having two the values in the aov are doubled for both assets. Three assets = three time the value etc.

Hope that makes it clearer what the issue is.

Cheers!

/Hannes

[bdancer]

> I think it was not like this before though. At least not in vray4.

This was always like this. Please, just write how do you expect this to be written, because I've no idea how to write 2 different shaders in the same render element otherwise.

[Hannes Drossel]

Hi bdancer ! Thank you for looking into this.

What we have in our scenes:

• Multiple shaders writing to the same aov.
• The different shaders outputs same or different data per shader to that aov
• The shaders are assigned to different geos.

What we get currently:

• All the shaders write their aov data to all shaders. Adding the result together.

What we want is:

• That the aov data outputted from one shader to only write that data into objects with that shader assigned.

Example:

• We have mask textures for different parts of a character.
• We want to output that mask as an aov for comp.
• That aov is added in lookdev so it is connected to the asset.
• That aov has a generic name like: FACE_MASK
• Later in shot production we might have more than one character. Both have this FACE_MASK aov in their separate shader networks.
• The data in the mask texture connected to the aov is different per character
• When rendering these characters we want the mask texture be output to the FACE_MASK aov per character.
• What happens now is that both characters get both textures in that aov with the data added together.

I will try this on an earlier version of Vray as Im pretty sure this was working before.

Thank you!

/Hannes

[bdancer]

> I will try this on an earlier version of Vray as Im pretty sure this was working before.

This was never working like you explained; AOV feature is limited to the way ExtraTex render element works.
I'll check if I could generate PatternID texture internally to make it work like you want.

[Hannes Drossel]

Thank you! That would be much appreciated!

[david.anastacio]

We had this "issue" a couple of months ago too, we had aov in a shader that we needed to export and that asset was copied a couple of times so the aov was not exporting uniquely for each asset, I ended up appending the name of each asset to the aov name.

The shader/texture aov could behave in a way that it would export only for the geometry the material is assigned to, maybe add a toggle for that in the material AOV.
But not chaging the overall extratex behaviour, if the extratex is used as a general AOV inside the elements it should still works as it does now. I know this is obvious, but sometimes when you guys alter a functionality of something you tend to break its functionality somewhere else, sorry.

Best,
David.

[bdancer]

This should work in todays nightly, could you please check if this is what you need?

[Hannes Drossel]

Thank you! Will check it out as soon as possible!

Is it available now or from tomorrow?

[bdancer]

> Is it available now or from tomorrow?

Now.

[Hannes Drossel]

This appears to be working perfectly!

Thank you for fixing this so swiftly bdancer !

Happy holidays!

/Hannes