Need help: High in game sensitivity causes choppy mouse look stutter / stepping.

[Ratha Wynter]

I would love some help in resolving an issue with Borderlands 2 look-stutter when using mid to high mouse sensitivity settings. This video shows a 60fps recording of Borderlands 2 with sensitivity setting of 100 at the start which then changes to 10 at the midpoint. My ideal sensitivity would be at around 50, but the issue is still quite noticeable at that setting. The video starts with a setting of 100 sensitivity to make the problem more visible since some people struggle to notice the issue.

NOTE: View video in full screen for best effect.
https://imgur.com/a/JHHTwvI

(EDIT: Replaced previous video for privacy reasons, updated with the video from this post.)

- Clean install of the game.
- Same issue with both Steam and Epic version.
- Borderlands 2: 60fps solid (140fps with Vsync off)
- Mouse: Old Logitech Trackman Stationary PS2 trackball with no hardware DPI settings.
- Mouse Smoothing has minimal if any impact. (Smoothing typically fixes this issue)
- Windows sensitivity at max, enhance pointer precision enabled. (Pixel level precision in windows.)
- Frame by frame analysis of sensitivity @ 100 shows ~20 pixel horizontal movement per update with most updates being either horizontal OR vertical changes with few diagonal movements leading to a stair-stepping type of juddering instead of a smooth diagonal one.
- Frame by frame analysis of sensitivity @ 10 sensitivity shows a blended diagonal movement (resulting in a vastly smoother display.) Pixel movements range between 1 and 5px with a horizontal and vertical component to nearly every frame update.

The following file seems to store settings which relate to the sensitivity including:
C:\Users\[UserProfile]\Documents\my games\borderlands 2\willowgame\Config\WillowInput.ini
- MouseSensitivity=60
- bEnableMouseSmoothing=true
- LookRightScale=300
- LookUpScale=-250

Though the settings within this file seem to be completely ignored by BL2. Confirmed? by editing this file, deleting all the settings, making it read only, restarting the game, and it having no effect on camera or sensitivity settings. I also replaced this file with the KFInput.ini file from Killing Floor 2, (which also uses the Unreal Engine 3 but that had no effect either. (This issue is also noticed in KF2, but to a lesser degree as KF3 feels good with a sensitivity setting of 30 instead of ~50 for BL2)

The in-game key binds, sensitivity, and mouse smoothing setting seem to be stored in the C:\Users\[UserProfile]\Documents\my games\borderlands 2\willowgame\savedata\[17_Digit_SteamID or 32_Digit_EpicID]\profile.bin in a ~535 to 850 byte hex encoded file. (However I still believe that the mouse smoothing setting is being ignored by the game or is too weak to compensate for the decreased pixel precision induced by higher sensitivity settings.)

I have severe framestutter sensitivity, get dizzy, nauseous, and have migraines when trying to play games that do not keep a solid 60fps with smooth view / screen scrolling. Feels like I may need some quite technical help from someone with a much deeper knowledge and understanding of the Willow*.ini config files in order to solve this issue. My hope is that by altering the ini / engine settings related to mouselook or some kind of look-input interpolation, or figuring out how to force Mouse Smoothing with a mid-range in-game sensitivity we may find a way to solve this problem not only for myself but for others.

Thanks for any help you guys can provide!

-

Windows 7 x64
Intel i5-4670k
24 Gigs DDR3
Nvidia GTX 960
512 GB Samsung 850 EVO SSD

[the_bat_turtle]

If you have a spare mouse lying around, plug that in to see if the problem persists. If that doesn't work, try resetting your mouse settings in Windows to default. I've never seen this happen before, so I'm sorry if I can't be of much help to you.

[Ratha Wynter]

NOTE: View video in full screen for best effect.

https://imgur.com/a/JHHTwvI

I borrowed a different[www.amazon.com] mouse for testing purposes. The first half of the video the in game sensitivity is set at 100, mouse DPI to its lowest value of 800. The visual stutter stepping was basically just as bad as my mouse. A LOT of pure horizontal and then pure vertical movement leading to a sort of jagged stutter stepping.

In the second half, turning in game sensitivity to 10 and mouse DPI to 2800 resulted in a very smooth mouselook as can be seen in the second half of this video. Frame by frame analysis reveals that nearly all of the movements are some form of diagonal movement.

To me this indicates that this is definitely a problem with how Borderlands 2 (and possibly the Unreal Engine 3) handle mouse / input interpolation via the sensitivity settings. Currently i am unable to run the same test on a completely separate computer to isolate other hardware or software settings being the cause, but leaning on my experience over the years, this feels like an issue with the engine or how the engine is configured more than an issue with my hardware.

To clarify: High ingame sensitivity results in very janky movement, even on a low DPI mouse.

If anyone would like to test this for themselves and help me confirm these findings: Turn in-game sensitivity to 100, and reduce the DPI on your mouse as far as it will go (400-800 should suffice) and try to get a nice slow, steady, diagonal mouselook movement in game. Then compare with lowest in-game sensitivity (10) and high DPI (2400-3600.)

Bonus points for anyone who wants to record their attempt at 60fps with a sensitivity switch in the middle for comparison purposes. Would be very interested in seeing other people's results.

[Ratha Wynter]

To help illustrate what is going on, here is a frame by frame comparison of the high and low sensitivity sections of the above video. I recorded these comparison videos from the original video inside of VirtualDub and fast forwarded / 'played' the video in a few places to help illustrate how the smoothness looked like in realtime or while advancing the frames more quickly.

Would have been nice if my capture software captured VirtualDub so you could see how the tracker was advancing, but it should be somewhat obvious when frames are advancing one by one vs when they're being played back at a more normal speed.

https://imgur.com/a/JHHTwvI - Testing different mouse (Parent of frame by frame videos.)
https://imgur.com/a/qwF9TY7 - Frame by frame - High in-game sensitivity.
https://imgur.com/a/icTiIkl - Frame by frame - Low in-game sensitivity.

[Вot]

I FIGURED IT OUT. It has nothing to do with sensitivity or DPI. It's the POLLING RATE or FREQUENCY. My mouse software is Razer, and in there is an options called "polling rate". If it's set to 1000hz, the stutter is horrible. Setting it to 500hz solved it.

[Ratha Wynter]

I cant speak to your issue specifically, but my issue was not caused by a high polling rate. It was solely caused by setting the in game sensitivity too high.

My original mouse had too low of a DPI to move at the speed needed, increasing the in game sensitivity caused the game to move the pointer very stiffly, to the point where it would no longer make smooth movements and would jump multiple pixels straight in one direction (horizontal or vertical) at a time.

I observed this behavior on low (100-200 DPI) and medium DPI (800-1600) mice with the sensitivity set too high in game. Dropping the in-game sensitivity was the only solution i could find, which meant getting a new mouse with better DPI / DPI customization.

My original mouse which was exhibiting this problem was a PS/2 mouse and to the best of my knowledge those were 'polled' (sent interrupts) at either 100 or 200hz.

I have not tested 1khz polling with my new mouse, but i know that turning DPI down, and in-game sensitivity up causes the issue for sure.

[JustDeBreezy]

We're you able to fix this? I also have the same problem. It just feels jagged and going vertical and horizontal.

[Ratha Wynter]

Originally posted by JustDeBreezy:

We're you able to fix this? I also have the same problem. It just feels jagged and going vertical and horizontal.

The only 'solution' i found was 'dont use high sensitivity settings in game because theres no smoothing / interpolation at high sensitivity.'

I ended up having to just deal with a sensitivity of about 25-30 (i needed closer to 50) until i couldnt tolerate the 'screen stutter' from the non-smooth mouse movement anymore. (Which didnt take long.)

Moved to a newer mouse a couple of years ago that had DPI settings high enough that i could drop the sensitivity in game as low as it'd go (10?), but never really played much BL2 after that because everyone had already moved on.