Disney released some interesting assets. I found very nice cloud render there. How can we do same shading with phx ?

[Paul Oblomov]

https://www.disneyanimation.com/technology/datasets

[Svetlin.Nikolov]

For clouds you better switch the Scattering mode to Ray-Traced, this would be the most important bit to the shading.

Here is a clouds sim and render tutorial with some settings: https://docs.chaosgroup.com/display/.../Static+Clouds

[Paul Oblomov]

I can't find a way to even mimic that scattering. Only some geo mode + vray volume scatter material with several layers

[Svetlin.Nikolov]

How do your results look right now?

[Paul Oblomov]

Like this using env fog. Kinda surprised
http://joxi.ru/brRQYZpSJaW0dA

Phx looks like a smoke. Hyperion uses some new techniques (IMHO).
http://joxi.ru/nAyb9KMhYxLZBr

Fastss2
http://joxi.ru/YmE9NM0t04KgQm

P.S. Lightcache ate all my 64gb for 2gb vdb. Kewl

[Svetlin.Nikolov]

Seems like your render step for the fog is very very large.

For Phoenix, wouldn't it look better with less opacity? Right now it looks almost solid.

Do you mean the Phoenix light cache or the V-Ray light cache?

[Paul Oblomov]

phx lightcache

less opacity - still like just s smoke. only fastsss2 looks close.

[georgi.zhekov]

Here is my go at the cloud. You can check my settings in the attached scene.
Rendered with Phoenix and V-Ray Next GPU.

[^Lele^]

serious <3

[Paul Oblomov]

Yeah. Still looks like smoke. This is different type of cloud (IMHO). And it now can't be rendered with phx, only with fastsss2.

[Svetlin.Nikolov]

Starting off with Georgi's scene, I got this:



This is with a build from yesterday, here is the scene as well: Clouds_scattering_Max2016.zip

The highlights for this kind of shading include:
- Use Probabilistic Shading from Phoenix's Atmosphere - 8 direct samples, 1 GI sample.
- BF/LC GI, progressive sampler, Ray bundle size = 8 for more responsiveness.
- Phoenix light cache off - it's better to turn it off with progressive.
- scattering = Ray-traced
- smoke color = pure white - this way light scatters the most
- simple smoke opacity = 0,13 - the lower this is, the longer distance the light rays will travel before scattering, but if it's too low, the smoke would lose its shade detail.

I think mostly everything else is using defaults.

Currently there is no scattering phase function in the Phoenix shader, which would allow you to get the dark edges of the cloud.

Cheers!

[^Lele^]

Indeed, the Mitsuba file has a strong (0.83 if memory serves me well) forward scatter of the HG type.