aiMatte weird behavior

[XtaaZ]

Hello!

On the last Arnold version (3.1.1), it seems that there's a problem: when using aiMatte on an object, even if the Opacity is set to 0 (black), it appears as 1 in the Alpha (so it's white).

On a previous version (can't remember which one, but one from September 2018 probably), it worked correctly.

Thanks a lot

[Stephen.Blair]

I don't see that behavior. Do you have a repro? (an ass file or scene that reproduces the problem)

[XtaaZ]

Hi, I attached a Maya scene (*.ma, created on Maya 2018). The plane should be black in the Alpha, but still appears white.

Thanks a lot!

aimatte-issue.zip

[XtaaZ]

Just noticed that if I check the Matte options in the Arnold Attribute on the mesh, it works correctly (object is rendered as a black matte and is black in the Alpha). I'll probably use this option 🙂
Thanks!

EDIT: if I check the Matte option in the Attribute of the mesh, the mesh doesn't appears in the N, P, Z, motionvector, etc AOVs. I want it in these AOVs, so I need to keep using the aiMatte shader 😛

[Anonymous]

i had this problem and tried a couple of things, in the end I switched to CPU render and it solved the problem