Volumetric Clouds (833530)

Here’s a GIF showing the improvements @auzaiffe made to the sunlight sampling. Now the lighting is more exact for those low sun scenarios. It’s quite impressive on very large clouds, like cumulonimbus.

7415879--907151--sunset.gif

15 Likes

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

In the latest Unity beta it looks like this:
7419044--907733--upload_2021-8-15_10-58-6.jpg
Maybe something was changed in the latest github or I am missing simething?

1 Like

Hey, why are you offsetting the center of the earth on the X-axis?

By default, the Y axis in Unity indicates the “altitude”.

7421819--908273--upload_2021-8-16_14-9-9.png

So the center of the earth must be underneath the origin of your level (which should be the sea level, if you want to keep things easily under control). That’s why the center of the Earth is at 0, -6…, 0.

There will be eventually improvements to how this is set (similarly to how the “Global wind” parameters are now set in the Visual Environment), to improve the consistency between all these systems that rely on a specific planet size and certain altitudes. In the meantime, don’t offset things without a very good reason. :wink:

1 Like

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

2 Likes

https://github.com/Unity-Technologies/Graphics/pull/5354

3 Likes

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…:smile:

7422866--908444--GIF 2021-8-17 1-25-56.gif

7422866--908447--GIF 2021-8-17 1-27-32.gif

3 Likes

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

1 Like

With the vertical wind we’ve introduced recently (available in the Master branch of the github repo), you shouldn’t need that, as you not only get X-Z movements in the shape noise, but also Y movement. Now, if the horizontal and vertical speeds aren’t the same, it will take a very, very long time for the clouds to “loop”. Try numbers that aren’t factors of one another to reduce the frequency.

If then, on top of this, you blend in randomly a volume that slightly alters the shape factor and the altitude of the cloud volume, you can do endless cloudscapes that will never repeat.

The thing is, timelapse with ultra-fast clouds are fun, but in general, during gameplay or normal scenarios, the clouds will be fairly slow, so seeing a repetition after 30min is really not the end of the world for many types of projects. With the vertical wind we’ve added, you can probably go for many hours without seeing a repetition.

And with the (pending) change that massively reduces ghosting, you can now have clouds that move many times faster than the speed of sound without any ghosting.:wink:

(I’m talking about “scrolling clouds repetition”, not “high altitude visible tiling”)

3 Likes

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?


Soon in a PR, no new noise needed.

8 Likes

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

1 Like

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

1 Like

Some irrational ratio might have been better though :roll_eyes:

Using an irrational ratio doesn’t change much given the low resolution of the noise texture.

1 Like

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.