Polygon Map Generation demo

  from Red Blob Games
Sep 2010, updated Nov 2013

The simplest way to explore the maps is to click Random repeatedly. Try the various Island Shape, Point Selection, and View options.

Flash version of map generator could not be loaded; try the HTML5 version instead.
Newer version of this project

Feel free to use these maps for any purpose, including commercial use. This is a map generator I wrote in 2010 for a game; I’m not working on it anymore, but all the code is available so that you can download and modify it for your own needs. I also have an HTML5 version that has slightly different features →

In a shape number like 85882-8, 85882 chooses the overall island shape and 8 is the random number seed for the details (random points, noisy edges, rivers). You can type in a shape number and press Return to generate that map. The details will vary based on the other options you’ve selected.

I wrote an article describing the algorithms, and how you can use all or some of the parts in your own projects. I generate island maps with constant slopes here, but you can use the same ideas for many different styles of maps. Notes:

The code is open source, using the MIT license (allows commercial use). I put it up on Github. Sorry, it’s not designed to be easy to reuse. I focused instead on explaining the concepts in the article, so that you can implement the algorithms yourself. I did not implement the Voronoi algorithm; I used an existing library for this.

The original demo I posted in 2010 is here. Changes: I took out roads; I added PNG export; I added byte array output (e.g. height maps); I added control over the number of points; I added control over the distribution of points.

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