There seems to be a lot of confusion about the maximum size of a level in UE4.

I doubt I’m going to be doing anything that even remotely pushes UE4’s limits for size anytime soon, but I’m kind of curious. A cursory glance reveals that people are saying anything from 2km[SUP]3[/SUP] to 20km[SUP]3[/SUP] is the maximum playable size for a given level. Even Epic’s own Trello card lists the implementation as “10-20km” Or alternately, I hear ‘IDK, use world composition’ a lot, which isn’t really an answer. Eitherway, that’s a fair bit of ambiguity.

There surely must be a point where co-ordinate precision starts to falter, or the physics simulation gives up. Does anybody know the real answer? Or is it one of these things that’s just inherently hard to measure?

2km from the origin is where you start seeing precision issues in first person, while 20km is the hard coded max size you can get to in a single map. In singleplayer, origin rebasing fixes the precision issues entirely for a map as large as you want with no consequence, while in multiplayer you still need to be mindful of server side calculations not being as precise at large distances.

That ^

Also just to be clear , origin re-basing is single player (offline) only thing right now , its not implemented for multiplayer scenarios.

So to put it in perspective:

The Map size for single player games is virtually infinite if you use origin re-basing and world composition
The Map size in multiplayer is limited to 10KM from the world origin in X,Y and Z or 20km from end to end i.e a cube of 20km x 20km x 20km (origin re-basing dose not work in multiplayer)

Large worlds + Physics + Multiplayer is the big gotcha…


Quick question: Could a game be designed with the following limitations to offset the usual problems:

A super large-world 3D Multiplayer space game, but without the need for a 6DOF system for the ships.
With interp MoveTo type calcs to move everything including weapons, thereby making physics less essential…
The gameplay would probably end up being more tactical based, not high speed fighter gameplay etc etc.

Origin rebasing is being added to multiplayer for 4.14, but it’s only clientside as far as I’m aware.

Might need to do some testing to know for sure, but as long as you keep the project from using physics, use clientside hit detection, and stuff like that, you could theoretically use MP origin rebasing for a larger world. Not sure about what “super large-world” implies though, that’s probably fairly large and might start causing problems elsewhere.

If you are talking about that pull request that is mentioned on other topic then its not really useful if you use physics or other calculations