Vray 3.3 for Maya

[sharktacos]

oh boy, oh boy!
http://www.v-ray.com/maya/features/sp3/

Some hi-lights:

• caching XGen primitives to a vrscene
• rounded edges attribute
• Stochastic flakes material
• falloff map
• Aerial perspective (atmospheric fade)
• Preview volume grid objects in the viewport
• Variance-based Adaptive Sampler [VBAS]

Wish there was more in the docs for this last one (which is one of the most exciting of all!)... I see the DMC sampler has as new "Use local subdivs" checkbox set to OFF since the new Variance-based Adaptive Sampler optimizes lights and materials automatically. That's a very different approach from this one.

I'd be interested in hearing more on the recommended method for optimizing a scene with this new approach. For example, how does the Min Shading Rate factor in? Also how does GI factor in (a secondary subdiv)?

Also does this make the V-Ray Quick Settings obsolete, or has it been updated with work to VBAS?

[vlado]

I'd be interested in hearing more on the recommended method for optimizing a scene with this new approach.

It's very simple - leave everything as it is by default and use only the max. subdivs and color threshold of the image sampler (Adaptive or Progressive). Works for most scenes. Some special cases might need more advanced treatment, but they are quite rare.

For example, how does the Min Shading Rate factor in? Also how does GI factor in (a secondary subdiv)?

The min. shading rate needs adjustment only in specific cases where you have difficult GI or reflection scenarios that really need better shading quality. The default value of 6 is close to optimal for most scenes that we could test.

Also does this make the V-Ray Quick Settings obsolete, or has it been updated with work to VBAS?

It's still useful as a simplified control panel for the renderer; it works fine with the variance-based sampler.

Best regards,
Vlado

[sharktacos]

That is indeed simple! Thanks.

[flat]

Is there any command switched to old behavior like VRay3dsMax?

[yolov]

If you're talking about the render settings UI - no.
If you're talking about the variance-based sampling - yes:
setAttr vraySettings.dmcAdaptiveMethod 0; - disables variance-based sampling
setAttr vraySettings.dmcAdaptiveMethod 1; - enables it
It will be automatically disabled for old scenes and only enabled for new scenes. The above MEL lines can be used to force switch it on/off.

[ivaylo.ivanov]

Also

setAttr vraySettings.rgbColorSpace 0;

[sharktacos]

Also

setAttr vraySettings.rgbColorSpace 0;

What does this do?

[flat]

Thank you very much!

[ivaylo.ivanov]

What does this do?

Restores the old temperature color space for the lights and the sky texture.

[jasonhuang1115]

Hi,

Is there a way to verify through UI that the variance-based sampling is active after I set it via "setAttr vraySettings.dmcAdaptiveMethod 1;" for old scenes.

Solved: I can verify that through the vraySettings node.

[sharktacos]

Hi,

Is there a way to verify through UI that the variance-based sampling is active after I set it via "setAttr vraySettings.dmcAdaptiveMethod 1;" for old scenes.

Solved: I can verify that through the vraySettings node.

You can also run

 getenv "[COLOR=#333333]vraySettings.dmcAdaptiveMethod[/COLOR]";

in the mel Script Editor. It will return 1 if it's on.

[jasonhuang1115]

Cool. Thanks sharktacos...

[yolov]

Just a small thing - it should be getAttr, not getenv:

getAttr vraySettings.dmcAdaptiveMethod;

[sharktacos]

Right. Thanks Alex.

[sharktacos]

Would it be possible, when "use local subdivs" is OFF, to have Vray display the subdivs it is actually using in the local subdivs of the material or light. This would be a value that is greyed out and non-editable, but it would be useful to know what Vray is doing under the hood, especially in those rare cases when one needs to enable local subdivs.

I guess this is a mini feature request...

Something that may be a bit more involved, but possibly useful is a multiplier for the local subdivs of a material or light when when "use local subdivs" is OFF. So if I set it to 2 it would double the amount of subdivs that are being automatically determined for that light. That would allow one to take advantage of the new sampler, while still adding a little tweak where needed.

good idea?