Feedback Volumetric Clouds

Can you share the post processing volume settings you used for these screen captures?
It does look pretty good

 

In the latest Unity beta it looks like this:

Maybe something was changed in the latest github or I am missing simething?

 

This looks super awesome, but makes me jealous now that Unity doesn't have a proper gizmo for light direction like UE has.

 

Maybe it's too early and too greedy to ask it for now...

Could we have the second layer control of the shape noise and erosion noise?
Or better one: two layers of density curve control and erosion curve control we can randomly blend them.

for now it's so easy to notice the clouds are loops as there is no second layer noise to reduce it.

i can so easily make loop gifs with these clouds....

 

That would be really good, water shader are a good example for this as well

 

Does it handle transition between cloud types well enough or it's just the motion of camera/clouds part?

Because currently volume system doesn't really support interpolation between animation curves causing abrupt changes instead of smooth transition when having different density curve (which could be done by simply interpolating between the values evaluated by all the curves at a point) or even the default presets, with the default presets I think many people will expect smooth transition when moving between volumes (sparse to cloudy or stormy, etc)

 

I have a question, How is the point for sampling cloud-HDRI (the non-local mode) determined?
Because moving camera doesn't really affect it at all (in y-direction or any other direction)

 

One more thing that stood out to me was how would you add support for something like Depth of field or any other effect relying on depth information?

 

How did you achieve this though?
Something like Stochastic sampling?

 

positionPS.y += (positionPS.x / 3.0f + positionPS.z / 7.0f);
such simple touch

 

Some irrational ratio might have been better though

 

Hey, I know. I am making a space simulator (https://store.steampowered.com/app/890520/How_do_you_like_it_Elon_Musk/) and Earth (so its planet center and its atmosphere) could have any offset. Because you could fly to the planet from any direction and side (and I am using a floating origin).

Atmosphere is supporting this why not clouds? Is this very hard to add?

I have a feeling, that if this feature will not be added now, it will never be implemented. Like PBS devs promised to implemented a PBS atmospheric scattering "later", and two years later we still don't have it.

So please, please, please, at least consider adding this parameter to the clouds system.

 

I guess they are just focused on getting the visuals and technical things correct at this point.
I don't think that it's very hard to implement those things so maybe after a couple of iteration they will focus on QOL stuff.

 

It maybe true, but everthing that will not get into Clouds system before the 2021.2 beta ends, will appear only in 2022.2. This is more than year and a half of waiting for no reason (if it is not that complicated to implement.) Also it is not just a QoL feature. Without planet center parameter Clouds simply will not work for a space sims.

 

This may be of use then

 

What about 2022.1?

 

I guess he was talking about something close to an LTS version

 

Oh I see, thanks.

Are you sure that there is no PBS atmospheric scattering implemented? Documentation says it uses Bruneton, Eric, and Fabrice Neyret. 2008 - “Precomputed Atmospheric Scattering.”

Or maybe you are talking about 'space' point of view and not just planet/ground perspective.

 

Btw, one thing that just stood out to me was that if someone going after a particular cloud profile (I'm talking about height based cloud shapes), then it would be impossible after the fix proposed here:

This will be good enough in most cases where devs aren't going for a specific look, but say they want Thicker clouds always at higher level and small clouds near the surface then we would be able to see visible patterns with this implementation (more visible when shape scale would be tweaked given the coefficients aren't really dependent on scale somehow) and also, it won't be consistent with what was initially intended. (most of the stylized scenarios will have some kind of problem with this I think)

Although, If adding second noise could cost significant performance then you could provide it as an optional feature alongside the current fix(as it would solve most of the simple cases) just like we have option for two cloud layer in the 2D cloud layer or the noise option in custom mode.

Also, Some people may want the pattern to be loopable (for creating GIFs ) so you should make these fixes optional as well

 

Yes, I am sure. It is calculated for the sky, but it is not applied to opaque/transparent geometry in the scene during the fog pass.

 

We really need some fixes for PBS sky.

• It not being optimized for dynamic time-of day cycle, I tested it with moving sun and the performance was pretty bad. ( I always use OnChanged update mode)
• The sunset scenario looks pretty bad (angle between -5 and -11 degrees)
• Height based fog doesn't really have spherical mode, which also is quite visible when zooming for a full view of volumetric clouds.
• In general we don't have spherical fog (even volumetric fog don't have a spherical shape and blending option in local fog doesn't approximate spherical shape at such a scale)

But we don't have anyone currently working on these systems like we have for volumetric clouds unfortunately.

 

What I was suggesting was this:

Code (CSharp):

1.  
2.     // We reduce the top-view repetition of the pattern
3.     const piInv = 1/Mathf.Pie; //I don't know math library for compute shader :P
4.     positionPS.y += (positionPS.x * piInv + positionPS.z);

This would reduce no. of math operations and future proof this for any resolution and scale

 

Totally agree. And I am afraid that the development of clouds will be stopped in the same way after 2021.2. That's why I am pushing adding the planet center to clouds in this release.

 

Agree.
second noise layer is important.

for now, the shape noise is used for the huge basic shape,
so you can not set the erosion noise too small as you need it to give cloud more mid sized detail.
or the basic shape of clouds will look like cartoon.
then you lost the ability to add small detail so the clouds will look blur.

To me,all pics showed by Unity team lack mid sized detail,
as they are using erosion noise for more smaller detail.

But it's personal art feeling, i can not talk it in a convinced way.

 

Unreal engine's volumetric cloud do give us a reasonable goal given they look particularly good and honestly they really match real world clouds, even the wispy upper layer clouds for which Unity currently recommends 2D cloud layer which as mentioned in a previous post just aren't good (at all)

The sky in this image really look so much better than Unity's implementation somehow (maybe post-processing difference):


Also, This part is really crucial for large project and small teams also tbh (I think so at least, given this would be system in unity for quite a few years from now on):


I really hope they are to implement these features in this release cycle otherwise it would become like all the other HDRP features which have just the most annoying limitation in place forcing me to change quite a bit of source code and stopping me from upgrading main project to newer versions.

 

From what I saw Unreal also implements two sets of shape and noise layer:


Also, they seem to have implemented sun halo, it give really good rainbow effect in sun/moonlight through the upper cloud layers.

FogVolume3 from Asset store also implements sun halo.

 

Maybe unity needs something like this:



(They support multiple planets too, which I can't imagine having currently in unity considering how it's set-up and volumetric cloud system is also not going to support that if I'm correct)

 

Are there any more updates planned for this @pierred_unity , because I didn't find any pull requests for volumetric clouds either and now the focus seems to have shifted towards HDRP 13 (unity 2022.1).
Things like more quality settings (full res option and such) as well as planet center/radius options are still not implemented currently .

Also, some feedback from my side would be to make Tilling and offset a vector3 instead of vector2.

 

RIP planet center position

 

I'd really love if you'd guys give focus on this nontheless. It does look quite good


Problems I noticed: There's grain and motion drag when the dragon is flying, but I guess that would be solvable. I also noticed that when you move along, then the cloud shape disappears with hard edges instead of fade.

Example: Check the wings. Left one has the motion drag, right one has some grain.



Other not so high use cases would be eg mountain fog.

 

I have a suggestion for inside rendering of volumetric clouds, like for close-up scene in RDR2 where we are inside the cloud, (I don't know if this could be viable) could you somehow feed the density data from volumetric clouds to local volumetric fog system? (It could handle small scale volumetric scattering quite effectively compared to volumetric clouds) (but you would need to add support for low resolution volumetric lighting if we want things like storm scenes or maybe UFOs )

 

Do the volumetric clouds move correctly in scenes with floating origin for large distance worlds?

 

Here's a vid to show the effect I meant in the post above. Is there some way to

* fade the cloud edges instead of having a hard cut?
* not have the clouds disappear in front of an obvious clipping plane. I tried using camera near clip adjustment, but that didn't help

 

These things are already addressed in the latest HDRP version.

You have option for density fall-off and also Ghosting reduction(which works quite well honestly):

 

One thing I'd like to add: This should be the end goal. Or rather a milestone.

@Fewes correct me please, but you made this in Unity afaik

 

Thank you. Do you have steps about how to install that? I have to try

 

Try adding these packages from git(in the same order) using package manager:

Code (CSharp):

1. https://github.com/Unity-Technologies/Graphics.git?path=/com.unity.render-pipelines.core
2.  
3. https://github.com/Unity-Technologies/Graphics.git?path=/com.unity.shadergraph
4.  
5. https://github.com/Unity-Technologies/Graphics.git?path=/com.unity.visualeffectgraph
6.  
7. https://github.com/Unity-Technologies/Graphics.git?path=/com.unity.render-pipelines.high-definition-config
8.  
9. https://github.com/Unity-Technologies/Graphics.git?path=/com.unity.render-pipelines.high-definition

Note: since development of main graphics branch moved to HDRP 13 now, you would need 2022.1 alpha to to get packages using this method or else manually find the last revision on git that was on HDRP 12.

 

Thank you very much, that helped! There's so many settings to toy around with

 

This is fantastic! Thank you for your hard working!

 

I love the volumetric clouds, the current implementation is really impressive so far, great job!

But I'm running into the same issue @SebLazyWizard mentioned in his initial posts: Clouds are only affected by one directional light. This makes it almost impossible to create a proper day-night-cycle (which is needed in so many types of games nowadays).
I understand that changing HDRP's "unique sun" approach certainly involves some work, but Unreals Volumetric Cloud system explicitly supports 2 directional lights (which covers almost all use-cases out there, either sun+moon or 2 suns), so it would be a pity if Unity decides to stick to a single directional light only...

Are there any plans to have at least up to 2 directional lights affecting the clouds?

 

Sometimes you really wish Unity would finally implement that play mode settings won't get lost after you exit play mode while toying around in it

 

Realism aside, look at that. The github version is miles ahead of the latest 2022 alpha, looks much better.
Few Issues though. First is, how do I get volumetric clouds to work on scene's camera? It doesn't render in scene, only in game view.

Second is, how would I get godrays? Frankly I'm not sure if shadows are working at all. Maybe it's just a problem with the github version.