Board Thread:General Mod Discussion/@comment-34923977-20180502002010/@comment-25841881-20180502003843

If I remember correctly - and I might not - the IDE Mevans uses is Eclipse. The mod, like all Minecraft mods and the game itself, is made using the language Java. The map is an image, made similarly to any mod texture. The mod reads the image, looking at each pixel, to determine what biome to make a given chunk be.