So I was testing the maximum playable space for my multiplayer project compared to arma 3 (this doesnt apply to singleplayer games since you can use origin rebasing & world comp for that)
It appears we have much less space than Arma 3, is their engine using something special for precision / origin rebasing maybe?
The land mass is Altis from arma3 and the orange box is the max kill bounds of UE4 for multiplayer before precision issues happen
According to 4.6 release notes:
The maximum size of an individual world has been increased to approximately 20 kilometers across. This is defined by the ‘WORLD_MAX’ constant in C++ code. It was increased by a factor of four (from approximately 5 km.) ALTIS Clocking-in at 270 km2, Altis truly is the star of Arma 3.
UE4 kill bounds: I got the bounds by going as far from the origin as I could before the player was automatically killed.
Exact bounds in editor CM is:
X -1048527,1048527 | Y -1048527,1048527
Is there any way to get Multiplayer Origin Rebasing feature or is spatial OS the only way??
I think, and I am just guessing here, that the problem lies in the fact that the engine for ArmA is specificly for ArmA and the UE engine is all-round.
I dont think the engine used with ArmA can be used for iphone, android and ‘simple’ 2D games. UE4 strength is it can be used for all kind of games. And as with everything in life: when you want it all, you have to make compromises
However, you could open up the UE4 source code and add some code for really large terrain support
Well, its probably that the networking in arma is more of an mmo type with a different origin/coordinate system, it would be interesting to know how exactly they are able to get greater view distances. Making a big terrain itself isnt the issue, its just when you try to view it from the sky at different angles all at once, for a land mass this size there is all types of terrible view distance artifacts and bugs. So there has to be like culling / rendering improvements to really support bigger environments like arma can. I dont mind seperating the map into different zones / servers though…
Why no “The Crew” map, that looks better, are 5.000Km2
I’ll like to see this of multiplayer and network better and like this thread with examples and tests.
I’ve yet to see a good solution to this. We wanted a seemingly huge world area and ended up just being very creative about how the land/oceans were arranged on the game map to keep actual map size down.
Without something like Spatial OS or the long lost feature of Replicated Origin Rebasing (I thought this was going to get added to ue4?) then the online playable space is about the size of Fortnites battle royale island. Im not sure if PUBG uses their own workaround for floating point precision / rebasing to get the bigger size, but ue4 mp bounds is about 4x more space than ue3/udk was, still not enough imo
Floating point precision pretty much goes wrong when you start hitting maps of around 1.5-2km, at which point you need to be using origin rebasing (which is easier said than done).
We’ve had to use it in HLL, otherwise we start seeing a lot of precision-related issues. In Satellite Command the levels could reach 50km+, but didn’t use origin rebasing because all movement code was done in double precision and was abstracted entirely from UE4.
EDIT: Someone asked me about this in PM:
Note: The vast majority of these precision issues comes from doing so many operations on the numbers themselves.
