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 3D Perlin Noise.
I would suggest using billboard sprites as dpadam450 said. I'd recommend reading two papers, "A Simple, Efficient Method for Realistic Animation of Clouds" by Yoshinori Dobashi (PDF), as he describes a way to represent cloud volumes. The second paper is on the actual billboard sprites, "Real-Time Cloud Rendering" by Mark Harris (PDF).
If you want really nice clouds, try http://wiki.patapom.com/index.php/Clouds. It the most extensive documentation on clouds I've found to date, but it is very complex. Good luck.
Fractal_VisionMember Since 11 Jun 2012
Offline Last Active Jun 19 2012 01:57 PM