The process of making such a mod is pretty straightforward:
1. Register every biome in your game with cartographer, by calling `cartographer.biomes.add`, listing the biome, texture names to use for each detail level, and an optional min/max height for those textures to be used.
2. Register items/item groups that provide "paper" and "pigment" for mapmaking, by calling `cartographer.materials.register_by_name` or `cartographer.materials.register_by_group`. You can optionally specify how much of a material to provide per-item, or let it provide 1 unit by default.
3. Add crafting recipes or other ways of acquiring the following nodes:
4. When integrating into a game, you can use `cartographer.skin` (skin_api.lua) to re-skin this mod's UI with your own textures and better integrate the mod with your art direction.