"First of all, let me clarify some things about the “infinite†maps: They're not infinite, but there's no hard limit either. It'll just get buggier and buggier the further out you are. Terrain is generated, saved and loaded, and (kind of) rendered in chunks of 16*16*128 blocks. These chunks have an offset value that is a 32 bit integer roughly in the range negative two billion to positive two billion. If you go outside that range (about 25% of the distance from where you are now to the sun), loading and saving chunks will start overwriting old chunks. At a 16/th of that distance, things that use integers for block positions, such as using items and pathfinding, will start overflowing and acting weird."
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