SimCity 4 terrain generator
This script generates a random grayscale image for a SimCity 4 region using the random midpoint displacement algorithm. To generate a region, enter the parameters below and click "Generate New Map". Note that generating large regions can be rather slow, so if you're using Firefox, it may complain about a slow script. Clicking "Continue" will let the script finish. Once it's finished, right click on the image, and click "Save this image".
If your browser allows you to select the image type to save to, save it as a *.bmp image. Firefox only allows downloading it as *.png, so in that case you'll have to convert it using Paint, or some other graphics software. Chrome doesn't allow you to directly save the image for some reason, so if you're using Chrome, click "Open Image" then right click "Save As Image" on the image that appears.
Once you've got a grayscale image saved as *.bmp, you can load it into SimCity 4 using these instructions.