Procedural Clouds

Started by nvseal, May 12, 2007, 10:02:04 PM

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bigben

Quote from: nvseal on October 06, 2007, 12:34:12 AM
I like it. The clouds can use some work of course but I do think it looks pretty neat. I'm going to do some work on my newer setup (after this render I have going is over) and try to accomplish some things with the logical disrtibutions and climate zones. After that, I'll send you the tgc if you would like to use it. And yes, I would be quite interested in the files. Thanks.

You've certainly got the gross shapes and patterns to a quite believable stage without anything that's too obviously "fractal-like". I'll send you a URL on Monday... I'm on dialup at home so even if I started now it would still be Monday before they're online  ;)

I'm having a bit of a play with this setup, using the existing clouds as belending shaders for clouds with similar settings but smaller details.

bigben

Attached a second image of a single cloud layer (altocumulus)  I don't think my extra fractal made too much difference when looking at the preview so I looked at some of the other settings.  This cloud layer had a good outline but not much detail within it.

The most significant difference in this image has been dropping the edge sharpness down as well as the density a little.  I think that with a bit more tweaking of these two settings you may find that your cloud fractals are a lot better than you think and I suspect that some of your new cloud layers may become redundant .... or you may find even better uses for them.

Did you get the animated version of TG2? It's very handy for running a series of renders with incremental settings to fine tune things.

Lucio


nvseal

Quote from: bigben on October 06, 2007, 07:42:41 AM
Attached a second image of a single cloud layer (altocumulus)  I don't think my extra fractal made too much difference when looking at the preview so I looked at some of the other settings.  This cloud layer had a good outline but not much detail within it.

The most significant difference in this image has been dropping the edge sharpness down as well as the density a little.  I think that with a bit more tweaking of these two settings you may find that your cloud fractals are a lot better than you think and I suspect that some of your new cloud layers may become redundant .... or you may find even better uses for them.

Did you get the animated version of TG2? It's very handy for running a series of renders with incremental settings to fine tune things.

I'm afraid I did not get animation. I'm too cheap (and to poor) to spend the extra $100.  ;D
Redundancy has definitely been something I've been watching out for in my newer cloud setups. I think in my newest setup I have basically eliminated it. Everything serves some purpose. However, I have yet to go back see what I could eliminate after a polish. A few tweaks here and there and I might be able to delete one or two cloud layers. Detail is also something which -- I think -- has been greatly improved since I first made this early study. In my current setup, clouds will usually (not always) look decent from as low as 200 and sometimes even 100 km high (which seems to be the strong point right now).

bigben

Quote from: nvseal on October 06, 2007, 06:02:44 PM
Detail is also something which -- I think -- has been greatly improved since I first made this early study. In my current setup, clouds will usually (not always) look decent from as low as 200 and sometimes even 100 km high (which seems to be the strong point right now).

Definitely a good sign that you're on the right track, and of course the images you've posted have also backed that up  :)  I'm running some animations of settings at the moment. I'll post them when they're done as they might provide you with some extra ideas.  Clouds are certainly very complex as it's like trying to combine two fractals to get a result. There's no single combination of a cloud's edges sharpness/density that will work well because it will also depend on the cloud fractal's contrast/colour roughness.

bigben

@nvseal: PM'ed a link to the terrain set for you

@everyone else: I'll release the files after some more checking of the terrain and adding a few other goodies ;)

bigben

Had another play with this file and amde a bit of headway. A couple of suggestions:

The altocumulus layer I was using as a test didn't change much with the different settings I was applying. This turned out to be due to a lower quality setting for the cloud layer. Bumped it up to 1 and things got much better although I ended up turning it into more of a cumuls layer. Dropping the fractals contrast and colour roughness got it back towards it's original frm but with better detail.

Where you have used a surface layer with fractal breakup, I'd tend to stick to settings of coverage 0.5 and fractal breakup 1, using the cloud fractals contrast and coverage adjust as respective substitutes (mainly just to reduce the number of nodes where tweaks are made)

For the cumulus clouds, my experimental duplication of the cloud fractal seems to be getting some ood results. Try duplicating a cloud fractal and set the duplicate as a blending shader for the original fractal, then divide the original cloud fractal's feature and lead-in scales by 100.

I'll post the image when it's done.

TheBlackHole

@bigben
So, after two years and three months, we're still waiting...
Must be either a piece of s*** computer or an illogically large render. :P
They just issued a tornado warning and said to stay away from windows. Does that mean I can't use my computer?

rcallicotte

Miss your constant updates and all of your experimenting, BigBen.  Thanks for sharing what we have here.
So this is Disney World.  Can we live here?

Kadri

I miss him too. I was a lurker at that times. I remember some topics he made that i read like an ongoing crime investigation .
The rainbow topic for example  :)

Kadri.