Pointer speed "too fast" even if sensitivity and acceleration slowest

[alexarnaud]

Context

Some visual-impaired uses screen magnifier (as the Compiz built-in, ezoom) and have difficulties to move the mouse and fix a specific area of the screen. They expect to be able to reduce the mouse speed.

Expected behaviour

When the pointer speed is slow the speed of the mouse should be really slow

Actual behaviour

Even if the mouse speed is slow the mouse pointer speed stay fast.

Steps to reproduce the behaviour

1. Open mate control center
2. Go to mouse
3. On mouse speed : switch acceleration and sensitivity from fast to slow

To reduce the pointer speed I've used xinput as described in this thread : https://askubuntu.com/questions/688270/mouse-speed-too-fast

MATE general version

1.18

Package version

1.18.2-1

Linux Distribution

Debian sid

[alete89]

Same here: Gx Gaming mouse in lowest DPI

MATE Desktop Environment 1.16.2

Debian 9 Stretch

[lukefromdc]

I've got a Chrombook fully converted to Debian(Chrome entirely removed) with the opposition problem due to a kernel issue: a very slow and unresponsive touchpad

[foxmajik]

@lukefromdc Okay then you're not really commenting on the right bug. Try finding a bug that is relevant to your issue rather than trying to hijack an unrelated bug report.

[foxmajik]

Anyways, the reason I came here is because it's 2019, this bug still exists and no one has even triaged this bug report yet.

Mate defaults with the sensitivity and cursor speed set to minimum (at least on GhostBSD) and yet the cursor speed is way too fast.

This makes the desktop virtually unusable because you touch the trackpad and the cursor acts like yuou've punched its newly born puppy and jumps all the way across the screen.

[alexarnaud]

Mate defaults with the sensitivity and cursor speed set to minimum (at least on GhostBSD) and yet the cursor speed is way too fast.

We're encountering the same issue on Debian too, the mouse speed is usually too slow for some of our users. We've implemented the support "Device Accel Constant Deceleration" downstream to make our users able to decrease the mouse speed.

Best regards,
Alex.

[Anaglyphic]

Hi MATE. 2.5 years from OP, and downstream means what exactly? :-)

Don't worry others experience it do, I am currently posting from a Fedora 32 MATE install, and my mouse is annoyingly fast and impossible for pixel-level accuracy for blender and GIMP same as Debian. (yes it's a high-dpi gaming mouse) but MATE mouse setting screen is all the way down, and xinput does not show this mouse supports Device Accel Constant Deceleration.

xinput --list-props 10
Device 'USB Optical gaming mouse':
Device Enabled (153): 1
Coordinate Transformation Matrix (155): 1.000000, 0.000000, 0.000000, 0.000000, 1.000000, 0.000000, 0.000000, 0.000000, 1.000000
libinput Send Events Modes Available (272): 1, 0
libinput Send Events Mode Enabled (273): 0, 0
libinput Send Events Mode Enabled Default (274): 0, 0
Device Node (275): "/dev/input/event5"
Device Product ID (276): 1241, 64081

I tried manually specifying it, trying all possible combinations of --type & --format, but nothing seemed to work. Guess this value needs to be instantiated by the mouse driver first? Well anyway, searching around, I've found that some people need to use Coordinate Transformation Matrix, and that definitely works for me:

xinput set-prop "USB Optical gaming mouse" "Coordinate Transformation Matrix" 0.20 0 0 0 0.20 0 0 0 1

Just saying. 5x slower and still being on the lowest setting in the GUI make it usable. I settled on 0.18 and then that gives me some control in the GUI like a normal user.

If we can't do this from the MATE control panel, can we have a blurb pop up when people put the sliders all the way left they might need to investigate xinput solutions or something? A clue? It's a thought.

Thanks!

[immerrr]

@Anaglyphic your workaround really helped, thank you!

[lukefromdc]

This suggests both minimum and maximum speeds could be made more extreme, plus some way to revert with only the keyboard in case you accidently get an uncontrollable mouse.