Any suggestions how to make Cumulonimbus clouds?

[eapilot]

I always found hero clouds to be a challenge in Terragen.  Especially how to control the shaping of the cloud.  Anyone have suggestions on how to approach a cloud like this?  Thanks in advance.  I will try to post some attempts in the next few days.

Thanks in advance.

[WAS]

Magic. 

No, but really a lot of it is luck of the draw (seeds). 

Easy clouds or v3 clouds masked to small area or at small radiuses to build a hero cloud may be the best option.

[Hannes]

Great clouds! It would be a nice challenge to try to recreate something similar.

[Dune]

The holy grail. Needs another kind of computing inside TG I guess, or a bit of luck and careful design up to a certain point. Noise is variable, and it's hard to control. I always have the idea that starting from a main big shape, then warping that into smaller outcrops would be the key, but I never really got into that.

[D.A. Bentley (SuddenPlanet)]

I wish Terragen supported the use of volume meshes, which would give you the ability to shape the look of your cloud in a 3D application like Modo/Blender and that would be the boundary of the cloud.

Not sure why thats not already in Terragen, as the app does support importing geo for objects on the ground.  A cloud boundry mesh (obj) is an obvious next step.  Hint Hint! 

[Dune]

I'm pretty sure Matt has this in his mind, but writing the code is another matter. Would be awesome, though.

[icarus51]

Hello guys.

Making Cumulonimbus has always been my concern. Here I put some tests and pictures done with Easy Clouds (even 2 or 3 layers) and a bit of Post Rendering, especially for Lightning and the top of the clouds (smoothing). Needless to say, they don't satisfy me but it's already a step forward.

I found that using the Easy Clouds - Cumulus Castellanus - with exaggerated parameters (eg Growth at 7-8 and Variation at 3-4 and Cloud Depth 11,000 and beyond and Density 0.8 - 0.9), pushed and inflated clouds came out with strange effects. No Density Fractal, only Clouds.

In practice, the cloud was shot at the Locality bubble generating flattening effects, as in real Cb, and other strange Incus-like effects but too similar to sectioned slabs, which is not a good thing.

Doing everything with a single layer of clouds would be magnificent.

I hope that the next updates or a new version of Terragen will improve this situation.


Greetings.

Claudio

[WAS]

We can't use GEO, but what we could probably do is create displacement shapes, with lateral, on a plane, to get our cloud column shapes, and export that terrain as a Vector Map. Than we can use that map anywhere as a either a depth map or altitude offset (filling int he bottom of the clouds with a sheet or something).

I did some quick tests  with just scalars and altitude offset and it's pretty easy to get some complex looking cloud shapes, just slow when feeding shader info rather than raster image.

[icarus51]

Hello

Another try for Cumulonimbus Clouds. No Density Fractal, Cloud Fractal or Blue node linked, only Easy Clouds and playing with Parameters and Random Seed.
I admit that this don't satisfy a maniac for Clouds like me but is a way for solution, simple and not breaks my head. Anvil is the very problem that i didn't resolve so far, patience... perhaps a Sculpting Cloud tool is the reply? Or a plugin?
Made with TG v.4.4.65.
No post-editing

[Kadri]

More tools would be good for sure.

I tried to make one just 2-3 weeks ago. It needs more work but you can get the shapes mostly with only surface layers restricted by different altitudes like in this example. I used only one V2 cloud (easy clouds are slow and not sure how much you can play with them) here especially to get faster render times.

[WAS]

That's very convincing even in it's current form. Modeling clouds with surface layers is definitely a way to go, but you're more limited to columns like these sort of clouds you show it seems.

[eapilot]

Kadri, I was wondering why you were using surface layers.  Is it using altitude parameters like a height mask?  I'll try that.

I took an old example from the Cloud Library that looked like an effective setup at first glance (post #107) 

https://planetside.co.uk/forums/index.php/topic,3691.msg84870.html#msg84870
Itused V2 clouds, which I eventually replaced with V3 clouds.  Everything looked different.  I'm trying to get back some of that sculptural form back by increasing cloud density. This setup uses 3 v3 clouds driven by one main density fractal.

[Kadri]

That's very convincing even in it's current form. Modeling clouds with surface layers is definitely a way to go, but you're more limited to columns like these sort of clouds you show it seems.

Thanks Jordan. I used that method especially to get faster render times and less errors.
With 2 and more cloud nodes i get sometimes strange, problematic shadows.
With layers it is faster and less problematic.
You could get any kind of look in theory.
I actually had to try harder (contrast, offset, thickness etc. parameters) to get the look you see.

In this thread for example ı used 2 clouds (one on the left the other a little on the right side)
with every one having 2 layers restricted by altitude:
https://planetside.co.uk/forums/index.php/topic,27571.msg274069.html#msg274069

[Kadri]

Kadri, I was wondering why you were using surface layers.  Is it using altitude parameters like a height mask?  I'll try that.

...

Yes exactly. I used altitude for masking-restricting.

[eapilot]

@Kadri I don't fully understand how the child input works with the surface layer.  Does the fractal piped into the child input replace the Parent mask at the specified altitude? I couldn't find a good explainer in the forums or the wiki.

I did a test mimicing using surface layers an slope constraints.  It was a little unpredictable on what the result would be.  Using two separate clouds is easier to compose, but if its causes more expensive to have multiple clouds, plus artifacts, then I might have to use the surface layer method.