vray 3.6 - ignore objects in secondary gone?

[delineator]

Bug or feature?

We used to use the vray brdf material option of "ignore objects in secondary" as a quick way to hide glass (for instance a rail) so we could grab the materialid of the object beyond it in post. In 3.6, this feature is gone.

I know you could accomplish the same thing with a wrapper, however, this is always done whenever the material is already applied to the object and usually after a few rounds of rendering, so the process of - creating a wrapper material, applying that to the object and then figuring out the texture uvw issues - is a non-starter for us.

Anyone else have this issue?

[konstantin_chaos]

Hi delineator,

The option is still available.
It is now called 'Invisible for Reflection/Refractions':



Regards,
Konstantin

[delineator]

Oof, ok, there are definitely some weird things happening. The switch won't work, unless the geometry is grouped. And then, if any plane within the group has a material with this switch set, the entire group is invisible.

Additionally, this is actually doing the opposite of what ignore objects in secondary did. Previously, ignore objects in secondary, when checked, would hide the material from the camera, but NOT the reflections. Maybe that was not as intended, but thats how it worked.

Now, the switch for "invisible for reflections/refractions", when working, hides the object group from reflection, but not the camera, and won't work for glass because of the necessary refraction thru glass. Again, we used this workaround because there isn't a built in easy switch to hide group/object/material from camera for compositing purposes.

Any suggestions on how to proceed? The removal of this feature is a real killer for our workflow and I'm not aware of any way in Sketchup and vray to accomplish what we need to accomplish.

[konstantin_chaos]

Ah I see. I think you are talking about the 'Only in Secondary' option.
It's no longer available. The 'Ignore objects in secondary' was just renamed to 'Invisible to Refl/Refr' and no functionality was changed.
On the other hand you're right, there is something wrong with it. We'll investigate the issue.

As for a possible workflow:
> Create a 'Override' material and apply it to the object that should be invisible
> Plug the normal material, supposed to be visible in reflections in the 'Reflection' slot
> Optional: If you want the object to also cast shadows you can plug the material in the Shadows slot as well
> Use 'None' for all the other slots

And here's the result:



This is preferred workflow.
It should render on the GPU as expected.

Hope that helps,
Konstantin

[konstantin_chaos]

By the way,
The legacy option can still be changed with a script if that's what you prefer:

def EnableOrDisable_OnlyInSecondary(materials, state)
  materials.each{|m|
    material_plugin = VRay::LiveScene.active["/" + m]
    if material_plugin && material_plugin.has_param?(:only_visible_in_secondary)
      material_plugin[:only_visible_in_secondary] = state
      puts ("> " + m + " :only_visible_in_secondary: " + state.to_s)
    end
  }
end
# The method can be called with different materials listed and the state of the option set to true or false
EnableOrDisable_OnlyInSecondary ["Generic1","Generic3"], true

Konstantin

[delineator]

Script should be great, I'll have to play around and see how we can incorporate it. And yes, your right, it was "only in secondary" - I got confused when I was trying to remember what we use.

Is "only in secondary" not compatible with gpu or some other workflow and that's why it was removed?

[konstantin_chaos]

Yes it's not supported on the GPU.
Another reason for removing it is that the option has issues with the way it's implemented.
We'll find a better way to make it work in the future and bring it back.

Konstantin