Bug in Multimatte isMATID

[Morne]

Hi all

To reproduce:
1) Take a VRaymat with an opacity map and stick it on a plane, set its Material ID Channel to anything 1 or above
2) Add a multimatte and tick isMATID with the relevant channel.
Here's the bug:
3) Any object behind the plane with a Material ID channel of 0, will mess up the opacity of the plane and thus also give incorrect multimatte.

Here's 2 workarounds (WHICH IS A MAJOR PAIN BECAUSE THIS USE TO WORK FINE)
1) All objects' materials behind the plane needs to also have some kind of Mat ID channel other than the plane and other than 0
OR
2) Don't use isMATID and use the object gBUffer instead


Beauty:



Broken isMATID (girl matID is on 1 and ground is on default 0)


Workaround using Object G-Buffer (girl gbuffer on 1 and ground on default 0)



Latest stable VRay build 3.20.03 (Although I did notice it in the 2.5 nightlies also - was fine in the stable 2.4 build)

[matanov]

Hm you are right, it's not working in newer versions. We will try get it fixed for the next SP.

[Morne]

Thanks Peter!

[Morne]

Any news on this?
It's still broken in 3.40.02

[matanov]

I will bump it up in the system.