Problem with cloud texture in animations

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Alcuin
Posts: 1
Joined: 30.07.2002
With us: 18 years 2 months
Location: Bonn, Germany

Problem with cloud texture in animations

Post #1by Alcuin » 30.07.2002, 10:07

Hello,

I have a problem with the clouds around the earth. When the time runs rather fast and I look at the earth from above a fixed position the cloud texture rotates in a strange way around the earth.
I've done a 320x240 animation in AVI format and zipped it -- it's here: http://www.wops.de/celestia-clouds.zip

Is this a normal behaviour?

Thanks,
Stefan.

chris
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Post #2by chris » 30.07.2002, 18:56

That's normal . . . the clouds are supposed to move with respect to the surface of the Earth, and it can look strange when the camera is fixed relative to a point on the Earth's surface. In reality of course, clouds don't move like they're a solid shell enclosing the Earth, but it's the best I could do given current graphics hardware :)

--Chris

Axel

Post #3by Axel » 31.07.2002, 09:50

Hi,

when Celestia was around 0.8 or 0.9 there was a fixed cloud layer which wasn't looking so interesting, although this was pretty realistic.

So I suggested to use a single, rotating cloud layer. However, we had several threads concerning multiple cloud layers for gas giants. I can't recall whether this was done by an added faked planet or code mod or in plain vanilla solarsys conf.

But if used for Earth, maybe together with some intelligent blending reg. to each other (say multiply) two tweaked cloud textures could mimmic cloud formation/development very realistically. :idea:

Anything more advanced would probably require dynamic texure modification during runtime (fractals etc.) and would likely put a high load upon the cpu.

Take care,
Axel

Thilo
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Post #4by Thilo » 06.08.2002, 01:17

I guess, if you put clouds to any fractal algorythms, they will not look like clouds anymore :D

NecroBones
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Post #5by NecroBones » 07.08.2002, 19:53

Thilo wrote:I guess, if you put clouds to any fractal algorythms, they will not look like clouds anymore :D


Not necessarily. It's just a matter of constructing the right fractal. :)

-Bones.
-Bones - http://www.necrobones.com/
111111111^2 = 12345678987654321


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