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OpenGL Clouds in OpenGL?

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Hey guys [img]http://public.gamedev.net//public/style_emoticons/default/smile.png[/img]
Well I'm trying to make volumetric clouds but I have no idea where to start.. Does anyone know a good tutorial how to make them or suggest a commercial free library that could achieve that more easily with out spending weeks to code it [img]http://public.gamedev.net//public/style_emoticons/default/tongue.png[/img] Also I don't want anything too cpu intensive... Just something simple [img]http://public.gamedev.net//public/style_emoticons/default/smile.png[/img]

They don't have to be really realistic or anything but I want to fly thought them, and change how dense they are etc.

I've made simple clouds in OpenGl and they look like this:

[img]http://dl.dropbox.com/u/80015266/clouds1.png[/img]

I like how they look, i use perlin noise formula to generate them so they are different each time, and I can adjust how dense they are.. the only problem is that it's just a plane..

[img]http://dl.dropbox.com/u/80015266/cloud%20plane.png[/img]



So I definitely need new approach to this [img]http://public.gamedev.net//public/style_emoticons/default/tongue.png[/img]

Well what I am trying in future is weather system, So i could get rain, thunderstorms etc
Thanks so much for your time and help [img]http://public.gamedev.net//public/style_emoticons/default/biggrin.png[/img]

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Use 3D simplex noise. Although, it is more performance costly. The cost can be reduced using interpolation. Edited by larspensjo

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You could have it like it is now (maybe some shaders to make it look 3D), and when you get closer use particles and fade the cloud texture away.

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[url="http://lmgtfy.com/?q=efficient+cloud+rendering"]http://lmgtfy.com/?q...cloud rendering[/url]
>)

or
http://lmgtfy.com/?q=realtime+cloud+rendering Edited by Yours3!f

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Hi there. I've been looking into clouds recently, maybe some of the research I've done could guide you towards a solution.

Perhaps the simplest solution is going from 2D to [url="http://stackoverflow.com/questions/6091468/how-is-a-3d-perlin-noise-function-used-to-generate-terrain"]3D Perlin Noise[/url].

I would suggest using billboard sprites as dpadam450 said. I'd recommend reading two papers, [url="http://nis-ei.eng.hokudai.ac.jp/~doba/papers/sig00_cloud.pdf"]"A Simple, Efficient Method for Realistic Animation of Clouds" by Yoshinori Dobashi[/url] (PDF), as he describes a way to represent cloud volumes. The second paper is on the actual billboard sprites, [url="http://www.markmark.net/PDFs/RTClouds_HarrisEG2001.pdf"]"Real-Time Cloud Rendering" by Mark Harris[/url] (PDF).


If you want really nice clouds, try [url="http://wiki.patapom.com/index.php/Clouds"]http://wiki.patapom.com/index.php/Clouds[/url]. It the most extensive documentation on clouds I've found to date, but it is very complex. Good luck.

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