It is really strange for such a configurable desktop environment like KDE Plasma that there is no way to change the mouse sensitivity in the settings. This is a crucial feature for me, because I don't want any mouse acceleration on my system. But when I change mouse acceleration to 1.0x, the cursor is much to slow. I hope this feature will be added in the future, I will continue to use the Deepin Desktop environment until then.
Please attach a screenshot of your mouse settings.
Created attachment 115911 [details] screenshot of the mouse settings in KDE Plasma 5.14.2 Betriebssystem: Reborn OS KDE-Plasma-Version: 5.14.2 Qt-Version: 5.11.2 KDE-Frameworks-Version: 5.51.0 Kernel-Version: 4.18.16-arch1-1-ARCH Art des Betriebssystems: 64-bit Prozessoren: 8 × Intel® Core™ i7-3720QM CPU @ 2.60GHz Speicher: 15,5 GiB Arbeitsspeicher
Thanks! The way to have zero acceleration is to set the "acceleration profile" to "Flat". Then the slider just determines the sensitivity.
I am a bit confused. I am pretty shure it said "Pointer acceleration" and you could set it from 0.1x to 20.0x . But after I installed all the updates, the mouse settings changed to what you can see in the screenshot. Anyway... I will try immediately if the "Flat" mode works as expected.
(In reply to Damian Höster from comment #4) > I am a bit confused. > I am pretty shure it said "Pointer acceleration" and you could set it from > 0.1x to 20.0x . But after I installed all the updates, the mouse settings > changed to what you can see in the screenshot. Anyway... > I will try immediately if the "Flat" mode works as expected. Yes, the old interface had that, but it didn't support the modern Libinput library and was using forcing your mouse to use old unmaintained drivers. But this new one properly supports using Libinput as a backend driver, and with Libinput, the way to turn off acceleration completely is to use the "Flat" profile. If you find that the new one doesn't work properly, please fine another bug to track that. Thanks!
Nope. Setting the profile to "Flat" does not remove pointer acceleration. In both profiles changing "Pointer speed" changes the pointer acceleration. Could it be that you get static acceleration in "Flat" mode and adaptive acceleration (whatever that exactly means) in "Adaptive" mode?
OK, it seems like to get zero acceleration and true 1:1 movement mapping, you need to set the profile to flat, and the speed slider to the middle point. Does that work?
No, only when I drag the speed slider to the left I get no pointer acceleration (in both Flat and Adaptive mode), but then the mouse is unusably slow. There does not seem to be big difference between Flat and Adaptive mode, in both modes the pointer acceleration changes with the slider.
Can you detect any difference at all between the "Flat" and "Adaptive" acceleration profiles? Sorry to sounds like such an idiot here, but I can't tell the difference myself and I'm not sure whether this is because they're actually identical, or I'm just not very sensitive to the difference.
No, I can't make out a real difference either. I wonder to what the acceleration could adapt to in adaptive mode.
Mouse KCM does indeed not change the acceleration profile on X11 libinput pointers. Simple way to see: xinput list-props on your mouse device. libinput Accel Profile Enabled is default 1,0. Changing to 'Flat' profile on GNOME changes this to 0,1. Change it to 0,1 through xinput and you'll no longer have mouse acceleration. I believe the mouse KCM is changing it to 1,1, which still results in mouse acceleration.
I have no experience with the KDE codebase, but I took a look around out of curiosity. At line 150 of plasma-desktop/kcms/mouse/backends/x11/x11_libinput_dummydevice.cpp, LIBINPUT_PROP_ACCEL_PROFILE_ENABLED is defined as a boolean. However, xinput list-props shows two booleans for "libinput Accel Profile Enabled". 1 0 corresponds to Adaptive profile while 0 1 corresponds to Flat profile. Might be a lead.
*** This bug has been marked as a duplicate of bug 398713 ***