vray object properties conflict in render layers?

[jasonhuang1115]

Hi,

I separate a character into two render layers (call it layer A and layer B) where each layer contains multiple objects of the character.
Therefore, I assign vray object properties node 01 to layer A objects and vray object properties node 02 to layer B objects, so I can control which part of the character is treated as matte surfaces in each render layer respectively (via layer override).

Meanwhile, I also want to assign different object IDs to multiple subsets of layer A and B objects via vray object properties nodes, and here comes the conflict as e.g. an object is designated with an Object ID via vray object properties node 03 in the master render layer and also designated as a matte surface via vray object properties node 01 in render layer A.

Is there a workaround?

[t.petrov]

Hi,

Have you tried to make NxM number of VrayObjectProperties nodes, which cover all combinations of matte options and object ids.
Unfortunately we don't combine different VrayObjectProperties, instead we use the one closest to the Node it is attached to.

Another option is to use the per shape ObjectID attribute (Select the shape and then go to Attribute editor->Attributes->V-Ray->ObjectID).

Hope it helps,
Teodor

[jasonhuang1115]

Hi,

Have you tried to make NxM number of VrayObjectProperties nodes, which cover all combinations of matte options and object ids.
Unfortunately we don't combine different VrayObjectProperties, instead we use the one closest to the Node it is attached to.

Another option is to use the per shape ObjectID attribute (Select the shape and then go to Attribute editor->Attributes->V-Ray->ObjectID).

Hope it helps,
Teodor

Hi Teodor,

When you say NxM number of VrayObjectProperties nodes, what does "NxM" mean?

Thanks!

[t.petrov]

N is the number of unique object ids
M is the number of layers
Then you have to make all the combinations of VRayObjectProperties, so at the end you should have N x M number of VOP nodes.

[jasonhuang1115]

N is the number of unique object ids
M is the number of layers
Then you have to make all the combinations of VRayObjectProperties, so at the end you should have N x M number of VOP nodes.

Hi Petrov,

I still don't see how an NxM VOP nodes setup will solve this issue.

The main problem is that a geometry is assigned with objectID in a VOP node and meanwhile also assigned as matte surface, "visible to GI", or other flags in another VOP node, no matter if this is happened in multiple render layers or the original master render layer. I have tried to achieve this level of control by attaching VOP node to the group's transform node, and/or combine with checking the "Disable" under VOP's General tab; still am unable to find a combination of flags that will give me this level of control. I mean, there are workarounds like using material ID to generate multimattes and the like, but they are not efficient when you are dealing with hundreds of geometries or more in the scene.

If my description is confusing, I can set up a sample scene for you to test.