What an incredibly useful tool this would be. A reflective function that would give a visual impression of the angle of incidence and reflection from the sun at any given time of the year.
I would give it the impression of casting light, as well as black lines with pertinent values such as angles, projected path, time of the year, ect.
Could be used together or independent of each other, depending on the presentation or design requirements.
This would be extremely useful for designing solar homes reflectors and what ever else you can think of.
It would also allow for solar collector and greenhouse placement relative to surrounding structures trees and terrain.
Designing solar concentrators and collectors would be a snap if angles of incidence and reflection could be determined and projected as needed.
Solarium's, greenhouses, overhangs, gardens, the list is endless.
Hey, while your at it, how about linear and fluid motion?