[Multi-touch-dev] [RFC XI 2.1] current issues

Denis Dzyubenko shadone at gmail.com
Tue Dec 7 13:54:37 PST 2010

On 7 December 2010 22:44, Henrik Rydberg <rydberg at euromail.se> wrote:
> Hi Denis,
>> I guess different kernel driver for different device _will_ give you
>> different data. Hence my question was in context of recent discussion
>> - getting events through slave devices vs. master devices - I would
>> expect the data to be "unified" so that clients won't need to have
>> device-specific workarounds. I wouldn't be surprised if some
>> parameters would need to be configurable - the only example that comes
>> to my mind right now is again width/height of the touch - right now I
>> do not know what the value means and just assume that value 255 (the
>> maximum for magic trackpad) means 50 pixels wide.
> The min/max of the major/minor (aka width/height) is actually not that important
> - they are all calibrated in devices coordinates, so using the same scale for
> all of x/y/major/minor gives you the best result.

well I still do not know what _is_ the scale. Actually I am not using
MTAbsX/Y right now - I mainly rely on the root_x/root_y properties.

I am writing this email from a macbook - at it feels like mac moves
the mouse cursor for the same distance on the screen as I physically
moved my finger on the touchpad (that is if you ignore acceleration
and move it slow) - that results in my next question - getting a
physical size of the device.

Best regards,

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