I recently started working on a physically based sky renderer as my senior project for my Digital Media Design major at the University of Pennsylvania.
I got the idea for this project one day while was staring out the window pondering senior project ideas, and noticing the pretty sunlight, sky, and clouds.
I will write from scratch a physically accurate, brute force simulation, based on the most accurate physics and data that I can get my hands on. This will involve writing a spectral renderer, modeling the atmosphere, simulating atmospheric (multiple) scattering, and much more.
If time permits, I will even add clouds. While one of my goals is to make a physically accurate simulation that matches real-life data and references, another of my goals is to produce pretty pictures of skies, which can be greatly enhanced by the presence of clouds.
With my finished renderer, I should be able to render blue midday skies, pretty sunsets, the shadow of the earth in the atmosphere during twilight, the blue glow of the atmosphere as seen from space, crepuscular rays, and more. I would like to make it more realistic than existing sky simulations in computer graphics. It will easily be far more flexible than any analytic sky model in computer graphics, albeit much slower.
I'm not implementing any particular paper. So far, I've learned a lot from Wikipedia, and I've gotten some ideas from graphics papers. However, the main resources I've used so far come from government organizations including NASA, NOAA, USAF, and NREL.
I will post details and progress updates to this blog in the coming weeks and months.