Slide the number to choose how many blocks you want in the generation and click the flag to see it generate. Also you can click the blocks to make them go away because i was bored (I know I can have the blocks run without screen refresh but I like it without it.)
All code by me. This took like 2-3 days to make because A: I've never used custom blocks before And B: I've never done anything even similar to this kind of thing. If you see blocks appearing and disappearing instantly, It's the block realizing that space is already taken and disappears to find an empty spot, also putting the number to the max is perfectly enough to fill the area, I know it isn't realistic with caves and mountains/hills because idk how to do that but i'm working on it.