[PATCH] ClickPad support v4

[Kevin O'Connor]

On Mon, Dec 27, 2010 at 03:04:46PM -0600, Chris Bagwell wrote:
> Since xf86-input-synaptics 1.3.0 handles (X,Y) jumps during finger
> transitions, if clickpad users set their EmulateTwoFingerMinW to 5 I
> suspect they will see a lot less big cursor jumps... but they will
> still see small cursor movement click operations.  Users could make
> use of AreaBottomEdge to shrink size of touchpad to work around the
> smaller movement.

I was playing around with this a little.

Setting "AreaBottomEdge=3800" did make the mouse jitter on button
press go away (at the cost of a smaller touchpad area).  (Of course,
this would still need to work once left/right/middle button detection
is implemented.)

I can also confirm that setting EmulateTwoFingerMinW=5 stops cursor
jumps when pressing two fingers.  With a larger EmulateTwoFingerMinW
size, whenever I touch a second finger higher up on the clickpad the
cursor jumps.  The distance of the jump is proportional to how far
away my second finger is to the first finger.  The cursor jumps back
if I lift the second finger before lifting the first.  Interestingly,
pressing a second finger lower on the touchpad does not cause jumps.
Also interesting - if I set "AreaBottomEdge=3800" and I press the
first finger in the button area, and then press a second finger higher
up on the touchpad, then I don't get a jump.  (Maybe because X ignored
the first touch and then didn't get confused on the second?)

-Kevin