there a code you might want to check out its in the tutorial section if i recall it was random dungeon and it does exactly what you want https://www.scirra.com/tutorials/999/ra ... node-based
I would start small but basically most world like mine craft n such uses a sort of a node and populate from it.
It just a theory. But can you place several sprite node key and make each environment a certain size so that it fits snug next to each other. In other word a enviromental dome. This might give you some sort of clue. I am trying to do it myself as well its alot of work and you might need some math nerd to help with it.