Atmospheric Scattering

[PanosK92]

I think it's time to get rid of those photo-based sky spheres 😄

Some resources:

• https://ebruneton.github.io/precomputed_atmospheric_scattering/
• https://www.scratchapixel.com/lessons/procedural-generation-virtual-worlds/simulating-sky/simulating-colors-of-the-sky.html

[PanosK92]

Done