[RFC PATCH v3 wayland] protocol: add wl_pointer.axis_source, axis_stop and axis_discrete events

[Carlos Garnacho]

Hey :),

The protocol looks quite nice to me, only one nit below:

On Thu, May 7, 2015 at 7:54 AM, Peter Hutterer <peter.hutterer at who-t.net> wrote:

<snip>

> +    <event name="axis_stop" since="5">
> +      <description summary="axis stop event">
> +        Scroll and other axis stop notification.
> +
> +        For some wl_pointer.axis_source types, a wl_pointer.axis_stop event
> +        is sent to notify a client that the axis sequence has terminated.
> +        This enables the client to implement kinetic scrolling.
> +        See the wl_pointer.axis_source documentation for information on when
> +        this event may be generated.
> +
> +        Any wl_pointer.axis events after this event should be considered as
> +        the start of a new axis motion.
> +
> +        The timestamp is to be interpreted identical to the timestamp in the
> +        wl_pointer.axis event.
> +
> +        The axes array lists all axes stopped with this event.
> +      </description>
> +      <arg name="time" type="uint" summary="timestamp with millisecond granularity"/>
> +      <arg name="axes" type="array" summary="the axes stopped with this event"/>

I gather this would be the place where you start kinetic scroll on X
and/or Y axes. Doing this from a single point is clearly needed,
although this is usually solved in other places through "frame" events
(there's one on wl_touch, and AFAICT there's another on the latest
wl_tablet drafts). Such frame event on wl_pointer would be mostly
useful for this axis_stop event (could save some needless work on
wl_pointer.axis too though), I wonder if we should aim for consistency
here.

Cheers,
  Carlos