Feedback Volumetric Clouds

I just bought expanse(asset for volumetric clouds in HDRP)

It has some settings that I think are really interesting and default clouds could greatly benefit from.

Look at the 38 min mark, he shows the different noise layers that are used by this asset, and it does have a lot more variety than the current system. especially the wispy kind of clouds.
The system also has a very good way of handling multiple celestial bodies along with multiple layers of the atmosphere. I think unity could use something similar.

Atmosphere:


Celestial bodies:
(Sun) (Moon)

The cloud settings:


This does really offer much more creative freedom and looks better than HDRP's default clouds currently.

 

Expanse is indeed amazing, seriously
The latest update improved the lighting of the clouds. It's the authors personal work now, not following any papers etc.
Has quite an amazing look, plus settings to model, improve performance etc. And the fog is really nice too, big improvement last update. Although HDRP's fog is also pretty amazing, i just wish there were more fog options, like height-fog, distance fog.. currently I make it up using an asset like atmospheric fog to apply fog to distances at a certain distance far away from the camera, which HDRP fog can't do. The atmospheric fog asset isn't volumetric though, so still hoping HDRP will add it oneday... It's also really important as a feature. Countless games use it and without it would look pretty bad. (satisfactory, Road 96 (built with HDRP, uses the asset I mentioned) etc).

Although expanse is awesome, performance is a bit problematic in OLD GPUs, like GTX 1070.
It performs very well on something like an rtx 2070 which in it's own right is somewhat old.
Although honestly it's not bad that you can't use it even on these old GPUs, it just takes a bit more to do it's work -- depends on your project GPU, project scale, GPU budget and audience target.

Although to be honest, I look forward to the improvements to unity's volumetric clouds in the future, which are currently pretty good with amazing performance, but there's still some work to do to improve the look of the clouds.
In particular with stratus and cumulus clouds.
Hopefully there's still improvements to the visuals though and this isn't the end

 

Has anyone attempted to utilize Unity's HDRP volumetric clouds in VR? I can get them looking good in scene view. Once I view them in VR, they turn blurry, lose color, and are basically unusable.

In scene view:


In VR:

 

Yes expanse really looks great and seems to have more cloud presets
Look at this video!!... I thought this was real life!!!

Seems like its using different more advanced wind pattern

 

Can I bump this? I really want to know if anyone has successfully used these clouds in VR.

 

How are people getting the sunrays shining through?

I've read the blog post on the volumetric clouds and made sure my volumetric fog was enabled and working. I did what it said to do with 2 options, I think it was max height and distance or something, but could not get actual sun rays to appear.

 

Hey guys, just wanted to chime in and say I'm happy to see Expanse being discussed here! I do agree it's not an apples to apples comparison---HDRP's built-in clouds take the cake for performance, so when you compare the Expanse demo reels (typically captured in 4K on very high settings) to live demos of HDRP's clouds, always keep that in mind.

I will mention that the 1ms figure is supposed to include volumetric fog, celestial bodies/stars, and the sky---the actual full-screen cloud rendering takes about 0.4-0.6ms. Though that's on pretty crunched settings, haha.

Pierre, big fan of the work you guys are doing and super impressed with the results. Excited to see how this continues to evolve!

EDIT: This is Brad from Expanse. I have no idea how to change my username from the garbage it is now lol.

 

Ah, if it isn't C-3PO's good ol' lost cousin C-903 the garbage beborp

Good to see your input here Brad.
Edit from Pierre: https://id.unity.com/ < --- to change UN

 

When the cloud is in thick fog it looks like it has some sorting issue I think:

 

Hey,
how would the advanced & manual cloud controls work? How do you create the textures, and what are they exactly for the two modes?
I've never really done something similar, and I'd really like to go beyond just the 'custom' preset. Tough to get the right look sometimes.

 

ah haah, I see it's just the age that can't be changed. Good eye Pierre.

 

Thanks for the response! I just realized I don't even have the anistrophy option on Fog. What Unity version should I be using for the options you say to tweak?

 

Thank you good sir.

 

@pierred_unity
I found a few issues with the clouds
1. The system uses a 'first' directional light shadow caster for lighting. Which means when doing any kind of time of day and including say a Moon switch there's a lot of hacking values to get the lights to switch. Had to dig to find this as it's undocumented and would be better if we could tell the cloud system what it should use as the dominate light source.

2. it looks like the lighting calculation doesn't take into account the intensity of the light into the calculation, just the color and direction which again means when doing a sunset we have to hack the lighting on the clouds to get it rendering correctly. It also doesn't take into account the lights resulting intensity as it's modified by the skybox atmospheric rendering.

3. When the dominate camera is switched the clouds reset their state (as far as offsets from wind etc) and we have no way of forcing an offset. So every time the camera switches the clouds return to their default starting positions breaking the realism. Please add a manual query / override to the offset so we can recover the state.

 

My apologies - I will address to you in the future.

These were linked issues when I was trying to fix the rendering bugs we were seeing in the clouds. To confirm we are using physically based sky. And after your message I took another run at it to see and it looks like it's connected to an issue where the clouds aren't taking the skyexposure into account. Which made it seem like the sun intensity wasn't being used.
We dim the exposure to transition to night and it causes the clouds to become super bright - in relation to the skybox.

I don't see any settings to translate the clouds? Adjusting the x and z of the clouds shape offset has no effect, how would we transpose the simulation? Any way to query the current offsets?

 

Is there a way to do something like this: (this is using unistorm)

This is what I have been able to create for night scene till now:


Is there a way to make the cloud's shape look more defined/increase the contrast?

 

I was able to get this look, thanks a lot.

The things I modified (for anyone in future):
Increase sun's lux value and then decrease it's intensity slider (To get the highlights):

Decrease PBS sky's exposure to counter increased sun's brightness (there should be a sunlight dimmer slider just like clouds for sky as well):

and increase cloud's density as suggested above:


I have one suggestion though:
All of this could be avoided if the sunlight dimmer value could be increased above 1 for the volumetric clouds:


This would save from changing setting of every other effect relying on sun's intensity.

 

Also, wouldn't it make more sense to change it to "Sun Light Multiplier"
Doesn't dimmer sound counter-intuitive?

 

Not the best-looking scene but still looks good to me

 

I've probably spent most of the last 2 months looking up now, oooft.
That third level is certainly a good max if you can get around that.

i did find from references there we still many cloud formations that were softer/smoother.
I seemed to have noticed in particular this definition was higher with larger Cumulonimbus clouds IR,
so i still think you're within a pretty good range so far while you steadily transition into a third layer.

I'm guessing at this point tuning the Quality steps from the first still wouldn't get you any closer to the 3 noise level there?

 

These clouds are looking awesome, but I have this problem with transparent objects like the sea, any fix for this?

Also it would be great if clouds could interact with point lights

 

I'm not sure if this is the right place to ask this but any idea on how to get a dynamic aurora borealis effect?
Should I create a new sky component with this effect built in it?

 

Hi there,

Testing Volumetric clouds in HDRP, for the most part they work and look good so great job! however they render of top of everything else in my scene:



Does this issue ring any bells? Maybe I'm missing something?

Just in case, running 2021.2.1f1 and HDRP 12.1.0 on OS X 10.15.4, Metal, Dual AMD Fire Pro.

 

This looks like cloud layers, not volumetric clouds.
Cloud layers (2D clouds) are currently bugged and render on top of things, it's fixed but patch is not yet released. Probably the upcoming one or the one after.

Volumetric clouds are enabled from the HDRP asset, global settings & camera frame settings.
Then you enable them by adding them as an override to a global volume, they're a part of the list.

 

This is indeed - as PutridEx mentioned, Cloud Layers and not the Volumetric Cloud component.
FYI the latest tech stream update fixes Cloud layers doing this.

 

Thanks to both of you!

 

I get a lot of flickering when trying to view these clouds in VR.

In addition to this existing scene where I see the issue, this also happens to me when I create a new scene, place my VR avatar in there, and bring in an existing volume profile containing volumetric clouds only. When I toggle XR Rendering off in the camera, the problem stops. I'm using the Oculus plugin. Single-pass instanced.

 

Sorry - I tried to repro in a fresh project and found that I couldn't. This led me to find that the issue was with a plugin I was using: Enviro. Specifically: a property called 'Exposure' in a Volume override called Enviro Skybox. I should have done tests in a fresh project earlier. Thanks for your patience!

 

@auzaiffe , I think the blending near the edges of clouds has some issues.


This is from the HDRP template (standing on top of the glass box).
You can see that the dark silhouette of the cloud creates an unrealistic outline around the cloud in overexposed situations.

 

Has anyone been about to Access the Cloud Preset on runtime? I really like the Presets and would love to be able to switch back and forth between them via Script, but can't seem to access the Volumetric Cloud override of the Volume.

 

@Skyler_Hawkins yeah, you can use Volume.sharedProfile.TryGet<VolumetricClouds>(out yourVolCloudsVariable); and then set presets or other variables..