Vray for Maya general questions/observations

[dariofx]

Hi everyone. I'm currently using Vray for Maya 2.30.01 on Maya 2013 SP2.

I'm still fairly new to Vray. I had been using Mental Ray for a long time, but now I'm really enjoying Vray.

I have a few general questions about Vray for Maya I was hoping someone could answer:

-Is there a way to render straight alpha (not premultiplied)?

-Is it possible to have different render elements at different bit depths. For example, I want the beauty, diffuse, spec at 16bit half float, but my velocity and zDepth at 32bit float?

-Is it possible to have the diffuse render element with self shadow, not just the flat color?

- Why is there not a Vray Spot Light, like there is for the other light types? Does it mean we should try and avoid the regular built in spot light, due to inefficiency with Vray or something?

- Does Vray for Maya have a pass contribution system? Is this what the Object ID system in Vray is for?

These are questions I been wondering about as I progress on my learning.

Thank you very much for taking the time!

[vlado]

-Is there a way to render straight alpha (not premultiplied)?

Nope; you'll have to unmultiply it manually in your compositing application.

-Is it possible to have different render elements at different bit depths. For example, I want the beauty, diffuse, spec at 16bit half float, but my velocity and zDepth at 32bit float?

Not for the moment. It has been requested before and is on the "to do" list, but is not implemented yet.

-Is it possible to have the diffuse render element with self shadow, not just the flat color?

There is the lighting render element, but it gives you the diffuse surface lighting along with any shadows. V-Ray does not distinguish between self-shadowing and shadows from other objects.

- Why is there not a Vray Spot Light, like there is for the other light types? Does it mean we should try and avoid the regular built in spot light, due to inefficiency with Vray or something?

There is no need to avoid the built-in light types. Anything that renders in V-Ray for Maya is specifically coded for V-Ray. So if you use a spot light, what gets rendered is a V-Ray spot light, which has the same parameters and behaves in a similar way to the Maya spot light - but it has been written from the ground up for V-Ray.

- Does Vray for Maya have a pass contribution system?

Not for the moment (not in the same way as for mental ray, at any rate). However it's rather high in priority on the "to do" list.

Is this what the Object ID system in Vray is for?

The object ID is for use with the MultiMatte render element, which allows you to extract masks for various objects or materials in the scene.

Best regards,
Vlado

[dariofx]

Thank you very much for your quick reply Vlado. Very helpful!