Comment 5 for bug 1042069

Revision history for this message
Andy Hayward (ach) wrote :

I suspect this behaviour is caused by the interaction of a couple of factors:

* the touchpad is anisotropic, about 2500DPI vertically but only 1500DPI horizontally
* both the synaptics driver and X are making making pointer acceleration calculations

These can be mostly fixed by tweaking the config; I'm currently using (add this as "/etc/X11/xorg.conf.d/50-touchpad.conf" and restart your Xserver):

Section "InputClass"
        Identifier "touchpad"
        MatchProduct "SynPS/2 Synaptics TouchPad"
        Driver "synaptics"
        # fix touchpad resolution
        Option "VertResolution" "100"
        Option "HorizResolution" "65"
        # disable synaptics driver pointer acceleration
        Option "MinSpeed" "1"
        Option "MaxSpeed" "1"
        # tweak the X-server pointer acceleration
        Option "AccelerationProfile" "2"
        Option "AdaptiveDeceleration" "16"
        Option "ConstantDeceleration" "16"
        Option "VelocityScale" "32"
EndSection

See also:
https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-input-synaptics/+bug/621432