gsoc 2013 idea - Customizable gestures

[Michal Suchanek]

On 14 April 2013 12:30, Peter Hutterer <peter.hutterer at who-t.net> wrote:
> On 13/04/13 01:34 , Michal Suchanek wrote:
>>
>> On 12 April 2013 13:50, Alexander E. Patrakov <patrakov at gmail.com> wrote:
>>>
>>> 2013/4/12 Peter Hutterer <peter.hutterer at who-t.net>:
>>>>
>>>> Hi guys,
>>>>
>>>> Unfortunately, the entry for gesture recognition in the synaptics driver
>>>> should have not been on the list. synaptics is the wrong place in the
>>>> stack
>>>> to do gesture recognition. we support a minimal set of gestures and they
>>>> already give us more headache than benefit. full gesture recognition in
>>>> the
>>>> synaptics driver would be an unmaintainable nightmare. for that reason,
>>>> even
>>>> if you could get it to work in a proof-of-concept I would not merge the
>>>> result into the upstream driver.
>>>
>>>
>>> I can understand this position. However, this also poses a question:
>>> what counts as a gesture and what doesn't. E.g., on a clickpad, one
>>> can click in the bottom right part of the pad in order to get this
>>> recognized as a "right button click". Or, one can swipe along the
>>> right edge in order to scroll. Are these two examples gestures, or
>>> not?
>>>
>>
>> They are synaptics-specific gestures. There is no reason why any other
>> absolute input device could not make such gestures available.
>
>
> In theory that is correct, but that we don't have the infrastructure to
> share these in place. Largely for historical reasons and because it too
> would make maintenance harder - another API to track. There's additional
> subtleties such as different capabilities, backwards compatibility to
> existing gestures, etc. We don't have a decent way to configure these
> either, properties help but are somewhat a rough way to control them.

So long as driver-independent gestures can express the legacy
synaptics gestures and the multitouch gestures there is no problem
with backwards compatibility.

If they cannot then they are kind of useless and it is understandable
that every driver wants its own gestures.

Thanks

Michal