UE5 Invert Mouse With No Settings

2023-02-18

(this is not official, this is just me jotting down for my own notes)

Occasionally, a more amateur developer will release a game made in UE4 or UE5 that doesn’t contain a settings menu that allows you to change mouse settings. This is an easy mistake to make, not everyone realizes that axis bindings have a sensitivity built in. But it sucks for players, who need to play inverted or with a lower sensitivity.

Config path

%LocalAppData%/{gameName}/Saved/Config/ the directory is usually Windows, sometimes WindowsNoEditor, just find the one that makes sense.

You need the name of the game. It’s usually obvious, but it depends on the project name, which is often a working title. For instance, United Heist is named "CoopPuzzle". hammer_space is "NegativeSpace". If you got the game off Steam, it’s the name of the executable in the steamapps folder (or in the library, right click, manage, show local).

Config entry

It’s tricky, because there are two ways to invert, and both depend on how the developer did it. If it’s a younger developer it’s likely they never renamed the look axis from "MouseX" and "MouseY", in which case it’s trivial to change sensitivity with this in Input.ini;

[Engine.PlayerInput]
bInvertMouse=true

[/Script/Engine.InputSettings]
AxisConfig=(AxisKeyName="MouseX",AxisProperties=(DeadZone=0.000000,Sensitivity=0.03,Exponent=1.000000,bInvert=False))
AxisConfig=(AxisKeyName="MouseY",AxisProperties=(DeadZone=0.000000,Sensitivity=0.03,Exponent=1.000000,bInvert=True))

Note the bInvertMouse and the bInvert=True are two different ways to invert. One of those is bound to work.

I’m not 100% certain which files the bInvertMouse=true needs to go into, i haven’t referred to the docs for precedence or actually checked with any specific game. But with United Heist it worked in Input.ini, Engine.ini, and only the invertmouse in GameUserSettings.ini.

I’m sure only one of those is necessary, just not sure which, and putting it in each works fine.