Medieval Fantasy City Generator
Oleg Dolya has made generators before, but this top-down generator of city layouts has become pretty popular.
In addition to producing nice, organic looking city layouts, it’s a good example of how simple geometry can be used to make something that looks convincing. It uses a top-down approach: Voronoi cells are used as a base, some of them are merged, types are assigned from the inside out, and then the blocks are subdivided into buildings.
It’s simple but gets the right feel, even though it doesn’t even begin to attempt a bottom-up simulation of city growth. And sometimes that’s the right call: if something looks right and feels right, it can work just as well as a more meticulous simulation. Maybe even better, if doing it the hard way takes too much processing time, or the generator needs to be looked up on demand.