Streets Of Rogue 2's latest dev diary is a crash course in proc-gen map building

The first Streets Of Rogue was an RPS favourite when it launched back in 2019 (we literally couldn't stop playing it), and we've known for a while now that its sequel, Streets Of Rogue 2, is due to arrive later this year. Ahead of the game's launch, developer Matt Dabrowski has started releasing a series of dev diary videos detailing his design process and how it's all coming together. The latest is about how he creates the game's proc-gen open worlds and biomes, and it's a fascinating watch if you've ever wondered how its particular blend of randomised chaos works behind the scenes.

The Road to Streets of Rogue 2 | Devlog 2 - Procedural Generation & Biomes 🗺️

I'd recommend watching the video in full above, but the secret essentially boils down to a lot of clever algorithms. Dabrowski says he uses these to first create a basic map, which he can then add geographical details to such as lakes, forests, mountains and oceans to help give the world a bit of shape.

The next step is then populating the world with cities, which requires another algorithm to help lay them out on the map and make sure they're spaced out. Dabrowski also says that both city placement and landscape generation is "going to be adjustable for players when you're first generating the map," so if you want a map with no cities, for example, that is 100% doable.

If you're a fan of island archipelagos, however, that may be a stretch too far, he says. "I don't think the NPC artificial intelligence would really know what to do with a [largely ocean] map right now, but hopefully, one day, it will and then you can, like, recreate Waterworld or something."

There's another algorithm Dabrowski uses to then create roads between these cities, while his map algoes (algi?) can also be called upon to help place landmarks on the map, which add additional areas for you and your pals to investigate.

In terms of figuring out what goes in those landmarks, that's all hand-crafted, Dabrowski says - and it's all thanks to Chunks (not that Chunks). This system is essentially a kind of level editor, and the game will be able to pull from a variety of these handmade Chunks to populate its landmarks and regions with.

There's a lot more in the video about how Dabrowski also uses Chunks to create his larger cities and biomes, and it's a neat deep dive into how this stuff actually works.

There's no word yet on exactly what date Streets Of Rogue 2 will be hitting Steam later this year, but you can still sign up for its first pre-alpha playtest if you want an early peek.