Set mouse pointer resolution a.k.a sensitivity interactively?

[Hi-Angel]

On Mon, Jan 05, 2015 at 08:43:41PM +0100, Simon Thum wrote:
> You can use xinput properties, those can also be set via inputclass sections
> if I'm not mistaken.
>
> man xinput should get you to it, if not install xinput. Two optionas can be
> used to achive what you describe:
>
> Coordinate Transformation Matrix (140): 1.000000, 0.000000, 0.000000,
> 0.000000, 1.000000, 0.000000, 0.000000, 0.000000, 1.000000
Simon Thum, man, I love you, thank you very much! You solved the
problem! From reading a docs I didn't understood wholly the matrix,
though. Suppose I set the values of the diagonal that accords to x and
y to 2. Then we'd have:

⎡ 2 0 0 ⎤   ⎡ 1 ⎤   ⎡  2  ⎤
⎜ 0 2 0 ⎥ · ⎜ 1 ⎥ = ⎜  2  ⎥
⎣ 0 0 1 ⎦   ⎣ 1 ⎦   ⎣  1  ⎦

The cursor couldn't appear now in the first pixels of the screen! I am
not sure that this is true…
Anyway, to sum up the steps to increase the resolution (or, at least,
the pointer speed):

$ xinput list #to list a devices
⎡ Virtual core pointer                          id=2    [master
pointer  (3)]
⎜   ↳ Virtual core XTEST pointer                id=4    [slave
pointer  (2)]
⎜   ↳ PixArt USB Optical Mouse                  id=10   [slave
pointer  (2)]
⎜   ↳ ETPS/2 Elantech Touchpad                  id=15   [slave
pointer  (2)]
⎣ Virtual core keyboard                         id=3    [master
keyboard (2)]
    ↳ Virtual core XTEST keyboard               id=5    [slave
keyboard (3)]
    ↳ Power Button                              id=6    [slave  keyboard (3)]
…

We see the mouse id is 10, next look at the list of properties:

$ xinput list-props 100
Device 'PixArt USB Optical Mouse':
        Device Enabled (140):   1
        Coordinate Transformation Matrix (142): 1.000000, 0.000000,
0.000000, 0.000000, 1.000000, 0.000000, 0.000000, 0.000000, 1.000000
        Device Accel Profile (265):     0
        Device Accel Constant Deceleration (266):       1.000000
        Device Accel Adaptive Deceleration (267):       1.000000
        Device Accel Velocity Scaling (268):    10.000000
        Device Product ID (260):        2362, 9488
        Device Node (261):      "/dev/input/event5"
        Evdev Axis Inversion (269):     0, 0
        Evdev Axes Swap (271):  0
…

Next set the first two «ones» of the property №142 to any other value
and see does the pointer speed now good for us:

$
xinput set-prop 10 142 2.400000, 0.000000, 0.000000, 0.000000,
2.400000, 0.000000, 0.000000, 0.000000, 1.000000

That's all!