TOD could do loads of things if the code was left more open.
Sun location in sky, global coords, TOD, and maybe a north direction, and you have the suns trajectory through the scene.
A pair of curves (probably can be generalised down to a quadratic or polynomial) for the sun intensity and colour, and the same for ambient intensity and colour.
Mie and rayleigh the same.
Once we have good ones then we can just copy the good ones, and those who want a bit more control can tweak them.
You could even just have the sun trajectory set the physical way, then define 'scene' parameters for different TOD, and interpolate between them.
Simply by removing parameters from the code and putting them in ini files means we get more out of Racer and make more interesting content, and Ruud has to put less work in, in theory
All very good potential, it just needs opening up rather than hard coding
Dave