How to render smoke in "Volumetric" mode with render elements available?

[TomGore]

Is there a possibility to render (CPU, Vray 4) a smoke in "volumetric" mode with render elements not ignoring the Phoenix smoke? I know phoenix render elements work in Volumetric Geometry mode and GPU rendering as well. But Volumetric Geometry mode is 10x slower in some scenarios. Is this possible technically for you guys to implement render elements (Vray Zdepth or at least Alpha) for Phoenix systems with "standard" Volumetric mode? I don't think it is hard to implement. At least alpha element would be very usable.
best,

[georgi.zhekov]

Hey,

Rendering of the alpha with the smoke should be working with Volumetric mode. If that's not the case with your scene - send it over and we'll take a look.
You can check our list of supported render elements here - https://docs.chaosgroup.com/display/...ements+Support

As for the other render elements I hope at some point we can have support for them in Volumetric mode as well.

Cheers,

[TomGore]

How to render alpha as separate element for Phoenix object in Volumetric mode? If there is a background under the smoke, it will render as alpha as well, resulting in white, useless alpha element. How to make it solo?

[georgi.zhekov]

Ah yes. Indeed, this case will require Multimatte or Cryptomatte render elements and won't work with Volumetric mode. We do have it in mind and it's in the to do list.

[TomGore]

I always keep myself asking - how other users go around these basic issues in PHX and Vray. Does everyone in post-production vfx, render in volumetric geo mode, wasting precious render time? Also - using environment fog or basic vray atmospheric haze is not compatible with "Volumetric" render mode - any kind of smoke stays above atmospheric effect. Without possibility to mask it (no alpha or cryptomatte), it is impossible to work with other volumetric effects. Unless you're on GPU, but then - other features are missing... What a Labirynth these days Am I the only one who needs such complex setups?

[Svetlin.Nikolov]

Yup, unfortunately it's a legacy we gotta get rid of step by step without breaking anything, so it's moving slowly. There are also things that gotta be changed in V-Ray as well. With gpu volumetrics it was much easier to get render elements without any special modes, since it was a brand new implementation and we already knew the possible issues from cpu mode.

These are high in the todo list and I hope we can get there sooner.

[TomGore]

Thanks for clarification, waiting patiently, meanwhile - improvisation.

[Svetlin.Nikolov]

Do you have a list with the most important elements for you? This way we can prioritize better which ones get implemented first.

[TomGore]

Thanks for the support - I think these are in order of importance (not only for me, I hope):

0. Good integration with existing vray volumetric effects (aerial perspective, environment fog). With that single point alone, the stuff below isn't really necessary.
1. Alpha in "solo" mode (like Fume FusionWorks Alpha render element)
2. A proper Zdepth Pass. Now, even with volumetric geometry zdepth pass doesn't contain soft smoke edges (it is sharply cut, which gives outlines in postprod).
3. Cryptomatee and Multimatte support.
5. All rest is not that important, perhaps Selective light for some users would be good.

Thanks,
Norman

[Svetlin.Nikolov]

Hey, got you, votes are added tot he issues, I hope we can have some of these going soon...

Thank yuo!