It’s another kind of grid-making, although it doesn’t produce regular sized regions, like a tiling pattern does. Nonetheless, it could be used as another way of generating walls with irregular edges, good for caverns and caves, though my own preference would be to have something regular for an interior space such as a dungeon.
But a Voronoi diagram might be a good way of making a regional map, with different kinds of terrain. So this is a documentation of the experiment. I’m not sure where it’s headed, but I’ll post updates to it as it progresses.
The first steps were making villages (where two points were close to one another) and towns (where there was a cluster with a center). Town/cities are not just the center of the cluster, but also extend to all other immediately adjacent cells in the diagram. Some coastline was also added at the top, as well. This is all somewhat arbitrary, and I’m fairly sure I’m not following the rules with rigor. But it does provide a way to make decisions, and it suggests differences in the landscape, unlike a blank page or any sort of regular grid would.
Next are some rivers, and a bit of shading to show the coastline more clearly. Rivers always follow the edges, since they define a separation between two areas (except for the delta wetland of the left river at the coast, which becomes the whole area. Areas around the towns were also shaded to highlight them a little more.
Roads sometimes follow edges, and serve as the boundary between two regions, but at other times, they go through the middle of a region. Again, it’s arbitrary choices (and the beginnings of stories about places, potentially). A road going between two areas serves to define the division between them. But a road that goes through the center of a region serves the region and is part of its character.
This is all rough diagramming at this point. The final version, even if it is drawn on a copy of the Voronoi diagram, will start with a clean copy of the diagram. But the rough version is fine for working things out.
The most recent version has added some more roads, as well as adding some features. Areas with a small region are likely a point of interest of one sort or another, so a couple of those have been marked with diamonds. Some forested areas of woodland and some mountainous areas have been identified, as well.