[RFC] libinput configuration interface

[Peter Hutterer]

On Tue, Feb 18, 2014 at 04:33:53PM +0000, Dominic Jänichen wrote:
> On Mon, 03 Feb 2014 11:02:42 +1000, Peter Hutterer wrote:
> > 
> > tbh, I'm not planning to support every potential option under the sun.
> > There's a fine and rather blurry line between what is a preference and
> > what is merely configuration because we can't commit to a single
> > default. I'd rather have less configuration options and support those
> > well and do the synaptics approach of supporting everything but being
> > quite bad at how the various options interact.
> 
> <snip> 
>  
> > As for the softbuttons config items, I'm somewhat leaning towards finger
> > movement in the button areas, but no clicks outside the button area. And
> > to actually trigger a button, you need to start inside the button area -
> > which becomes easier when you have proper finger tracking (synaptics
> > currently doesn't). 
> 
> Does that imply the following use case will be supported?
> 
> Being used to TP trackpoints, I am using the index finger outside the 
> button area (on a touchpad that doubles as one hardware button) and the 
> thumb to "click".
> I'd expect to able to move the pointer with the index finger while 
> clicking, disregarding slight thumb movements while doing so.
> 
> 
> This seems to very difficult to archieve (if at all) with the synaptics 
> driver; the points jumps widely, especially if the index finger is 
> removed from the touch pad immediately before clicking.
> 
> I can imagine that this boils down to having areas insensitive to motion, 
> but still working as softbuttons.

The set of touchpad patches I sent out recently already handle this by
default. When the physical clickpad button is depressed, the driver picks
the finger that is pressing the button (sometimes guessing, but hey...).
That finger cannot control the pointer movement until the button is released
again.

In your specific use case, the driver would see two touchpoints and it will
select the one closer to the bottom edge as the pressing finger (i.e. your
thumb). The index finger can still move while the button is down.

Cheers,
   Peter