Say that you have a city builder, and you want to generate some building between your nicely curving roads. Or you are generating your cyberpunk city, and you put in a lot of work to avoid it being a boring grid. Or you’re doing urban planning for a real city, and you need to drop in some building so you can see what it will look like when it’s actually built. But the places to fit buildings are all kinds of weird shapes: how do you figure out the shape the buildings should be? And if you make a small tweak to the roads, how do you keep the parcel subdivision persistent so the new version isn’t too different from the old one?

Enter Procedural Generation of Parcels in Urban Modeling, a paper by Carlos A. Vanegas, Tom Kelly, Basil Weber, Jan Halatsch, Daniel G. Aliaga, and Pascal Müller. In it, they discuss a method to take a city block that can be an arbitrary shape and divide it into parcels to place buildings on, one robust enough to handle live editing.