Atmospheric scattering

This weekend I got around to implementing the atmospheric scattering approach described in "A Practical Analytic Model for Daylight". It is basically a simplified model of the scattering that happens when light travels through air, with the light from the object being out-scattered, and sunlight and skylight being in-scattered. The amount of scattering is determined by the amount of turbidity in the air. Higher turbidity leads to higher haziness or cloudiness in the air. The result can be shown in the following renders, the first one with low turbidity and the two last ones with high turbidity:







References:
A Practical Analytic Model for Daylight