This is just a collection of links I think are interesting for procedurally generated maps in games.
First up, a video presentation of the methods used to randomly generate maps in Sir You Are Being Hunted.
Second is not about randomly generated maps for games specifically, it’s about the visualization of algorithms, but some of those algorithms have results that could be interesting, and being able to see visually how they work really helps imagine how they could be used for this purpose.
Then we’ve got an article on map generation using voronoi polygons.
Then we have one about trying to correct what he calls the “nebraska problem” while developing the game The Witness. He has a follow-up where he shows other patterns and there’s a few other useful ones listed here.
And last this blog sometimes also has interesting things. Again the focus of the blog is on visualizing interesting math, not procedurally generated maps, but some things are good inspiration, like the liquid in a porous material the idea of a Stolum Number or the Cheerios effect a fractal Brownian tree placing dots based on two distance rules, automatically clustering cities, or the tracks of a bicycle.
As they point out in the Sir You Are Being Hunted video, it’s easy for someone new to this to think they can just throw perlin noise on something and that’s good enough, but the most interesting maps have more to it than that.