[RFC] protocol: Extend wayland seat with interfaces for sensor inputs.

[Thomas Daede]

On Thu, Aug 1, 2013 at 3:39 AM, Stefan Schmidt <s.schmidt at samsung.com> wrote:

> +    <event name="motion">
> +      <description summary="Motion event coming from the compass sensor">
> +       Updated sensor data available from compass
> +      </description>
> +      <arg name="x" type="fixed" summary="x-axis"/>
> +      <arg name="y" type="fixed" summary="y-axis"/>
> +      <arg name="z" type="fixed" summary="z-axis"/>
> +    </event>

These events don't have any units, and there isn't any particular
information about the sensor passed either. Is this supposed to be
read out of band? Presuming the motion integration happens in the
client. it's very important for a coordinate system to be defined
between the accelerometer, gyroscope, and compass, and information
like sensor bandwidth is also important.

Sensors that combine all three of the above with an integral IMU
processor are also becoming more and more common - that's at least one
more type that we will need. I definitely think the interface should
be designed - the abstraction has to be somewhere, and I'd prefer it
here rather than every client accessing the devices directly - but I
want to make sure that this is possible with all sorts of devices in
the future.

There a number of other devices that I'd like to see implemented in
this manner - for example, 3D mice. In this case, unlike the motion
sensors, window focus does matter.