A common use-case for clickfinger is to use the index finger for moving the
pointer, then triggering the click with a thumb. If the index finger isn't
lifted before the click this counted as two-finger click.
To avoid this, check the distance between touches on the touchpad (on
touchpads reporting resolution values anyway). If the touches are too far
apart, don't count them together (or specifically only count those close
enough together as multi-finger).
The touch area is uneven, it's wider than high. Spreading fingers horizontally
is more common and this also makes it easier to rule out thumbs which tend to
be well below the fingers.
http://bugs.freedesktop.org/show_bug.cgi?id=90526
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Touches in the exclusion zone are ignored for palm detection and don't move
the cursor. Tapping however triggers before we know whether something is a
palm or not, so we get erroneous button clickst.
If a tap happens in the top half of the touchpad, within the palm exclusion
zones, ignore it for tap purposes. To avoid further complicating the state
machine simply pretend there was a movement > threshold on that finger. This
advances the tap state machine properly that no button events are sent for
this finger.
https://bugs.freedesktop.org/show_bug.cgi?id=89625
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>