Developer Mode includes a Planet Editor user interface for editing the different types of procedurally-generated planets. To use it, click
Editor in the developer menu and then click
File menu, you can load the files for any type of planet. A user interface for modifying the planet will be shown on the left, and a graphical preview of the planet will be shown on the right.
Planets are rendered using one or more "layers" stacked on top of each other. The planet editor allows you to add, remove, and modify any of the layers of a planet. As you make changes, the planet preview will update (which can take a few seconds).