u/lukeman3000

When changing focus with the motion tracker, it bothered me how instantaneous it was. So I changed it - now it fades over a given period of time (in this case, 150ms).

It's a fairly subtle change but imo adds a lot

This was a long time coming.

The mouse in Alien: Isolation has been broken since it released on PC nearly 12 years ago. There are a variety of things wrong with it. I spent last weekend reverse engineering the game (with Claude's help) and fixed everything I found. First things first:

https://github.com/lukeman3000/alien-isolation-mouse-fix

https://www.nexusmods.com/alienisolation/mods/173

Edit: It might be possible that the fix doesn't fully work in the DLC - I need to test this (I've only tested in the main game so far). I did get one report of radios not working in the DLC; still not confirmed if this is due to the fix or not, but I'm looking into it.

Let me know what you think. If you're interested in reading a write-up on the issues, I've left that below:

The four problems

1. Low-speed deadzone (normal gameplay): If the mouse is moving too slow the output is greatly diminished, such that the mouse can feel like it "sticks" at times.

Fix: NOP two instructions that are responsible for wrongly interpolating mouse movement at slower speeds.

2. Mouse smoothing (cinematic camera: rewire panels, lockers, vents, etc.): When interacting with a rewire panel or hiding in a locker, for example, the camera feels substantially different as compared to normal gameplay. One aspect of this discrepancy is a moderate amount of smoothing that's applied such that the mouse "drifts" - the camera movement lags ever so slightly behind the mouse movement.

Fix: Make sure that where the user puts the mouse, and where the game puts the camera, are always in sync.

3. High sensitivity (cinematic camera: rewire panels, lockers, vents, etc.): In addition to mouse smoothing, these views also have significantly increased sensitivity. And not only that, but the x and y axes actually have different multipliers. In fact, the x axis (yaw) is ~12.4x while the y axis (pitch) is ~3.9x more sensitive than they should be - a wild per-axis asymmetry (which is why these views felt wrong beyond just "too fast").

Fix: Scale each axis by a unique factor to normalize and match input within ~0.001%. In short, these views should feel virtually identical to normal gameplay.

4. Awkward look limits (cinematic camera: lockers, Security Access Tuner): When the player enters a locker, the mouselook is restricted to a very tight cone of vision. This can feel somewhat claustrophobic and seems unnecessary (possibly done with controllers in mind). Additionally, when using the Security Access Tuner, the camera is inexplicably allowed to move within an extremely small range (which can feel unusual).

Fix: Expand the camera range inside lockers, and lock the camera in place when using the Security Access Tuner. Both are adjustable in the config file.

The end result: No deadzone, no smoothing, no mismatched sensitivity, and more natural look limits. Experience the game as it should've originally been shipped - with essentially raw input.