Design Journal: Creating Maps - Found Coastlines

For the past few weeks, I've been experimenting and tweaking around with generating maps using GIMP and Wilbur. I've looked at a number of tutorials on Cartographer's Guild, particularly RobA's tutorials and Arsheesh's Eriond tutorial (as well as +Keith J Davies' methods for creating mountains). I've learned quite a bit in the process.

I have become quite fond of using "found items" for coastlines. In my case I used a radar map of Titan's north pole, reversing the shapes of the lakes to become the land. It underwent some heavy processing to get to the final form. Using a variety of methods, starting from the regional maps tutorial and transitioning through various techniques used in the Eriond tutorial I was able to go from this:

 To this:

To this:

And, finally, this:

The great thing about this method is that it can used with all kinds of naturally occurring shapes. Shadows on a wall. Stucco patterns. Puddles of water on concrete. Just snap a picture and start doing some editing on it and the result will likely be a pretty convincing, randomized but not too much so, coastline.

Next up, I'll talk about the pain I went through creating heightmaps in GIMP to be used in Wilbur, and some lessons I learned in the process.