i love speedtree tool. its a great example of how relatively simple algorithms can make natural complexity. also a great example on how to visually make things seem real while cutting as much corners as possible is that people used to fake bounced light through a room simply by making the backs of objects emit a fraction of light caught on the light facing side.

as people cant actually at observe arbitrary speeds and bandwith, you can skip most of the universe when visually representing it, to an extreme degree.