How to make a game without requiring copy-pasta'd terrain.

[Abriael]

I would like to point out another way to save memory while making large, detailed worlds. I can't remember the name of the technique, but there is an algorithm that causes very distant objects to be rendered in simple fashion, and gradually become more complex as the player approaches them. The idea is that it is pointless to have these very distant objects finely rendered, since the human eye can't discern

That's LOD, and FFXIV has it.

It's not to save memory by the way, it's purpose is to lighten the stress on the video card.