how to: override material as render element

[fraggle]

Hello,
how can we get an override material in the render element instead of doing 2 renders (beauty pass + override mat pass)?
Thanks

[MoonDoggie]

Can you do what you're trying to with a VRayExtraTex render element?

[Dariusz Makowski (Dadal)]

Can you do what you're trying to with a VRayExtraTex render element?

That was my 1st thought too but I think he want to do override on only 1 object or set of objects not entire scene.

[fraggle]

thanks,

I'm trying to override the entire scene as render element, not only one object.
VRayExtraTex works with map/texture texture not with material.

[DaveKW]

We wanted to do this a while back and ended up using RPManager.

[fraggle]

We wanted to do this a while back and ended up using RPManager.

Thanks,
I just have a look to RPmanager screenshot and I don't see any override material button. Is there any extra step involve before you run the script to get an override pass?

[DaveKW]

The material override is in the Renderer Setup tab under 'Global Switches', just like it would be using the normal Max version. What we do is create our base render on the first pass with Mat Override unticked, then create a second pass with it ticked.

We then shuffle the RGB of the 'override' render into a new render element in Nuke.

[fraggle]

Thanks, so basically, RPManager works like a batch render script?
Two render are necessary to get the beauty and the Override pass or are both pass done at once?

The material override is in the Renderer Setup tab under 'Global Switches', just like it would be using the normal Max version. What we do is create our base render on the first pass with Mat Override unticked, then create a second pass with it ticked.

We then shuffle the RGB of the 'override' render into a new render element in Nuke.

[DaveKW]

Yes, you end up with two renders, but we use Nuke to merge them into one multi-channel EXR.

[AJ Jefferies]

I'm pretty sure that Vlado has explained that a separate 'material' pass for a whole scene can't simply be a render element as changing a material affects everything in the scene. Basically, V-Ray would need to calculate two different sets of GI, reflection, refraction...etc.

For example, if your material 'render pass' was a refractive material and you had refractive caustics enabled in your render settings, it would have to calculate two different sets of caustics.

Does that make sense?

[bigbossfr]

You can use a VRayBlendMtl, add 2 materials, and render each submaterial with a material render element.

[Dariusz Makowski (Dadal)]

He would have to make vRayBlendMtl for each material in his scene I think. Bit of work but it could work!

[fraggle]

Thanks for the input.
I am not aware about what is under the hood, but as a user, I simply would like to get a "kind of" override material in a render pass element. Same request can be apply to the vray toon outline.

I'm pretty sure that Vlado has explained that a separate 'material' pass for a whole scene can't simply be a render element as changing a material affects everything in the scene. Basically, V-Ray would need to calculate two different sets of GI, reflection, refraction...etc.

For example, if your material 'render pass' was a refractive material and you had refractive caustics enabled in your render settings, it would have to calculate two different sets of caustics.

Does that make sense?

[fraggle]

Thanks, sure that's going to be a lot of work and tricky when you already have a lot of VrayBlendMtl in the scene.

He would have to make vRayBlendMtl for each material in his scene I think. Bit of work but it could work!