generic touchscreen calibration

Tias tias at
Mon Sep 14 12:26:55 PDT 2009

Søren Hauberg wrote:
> Hi,
> 2009/9/10 Tias <tias at>:
>> In the end, I had to hack up the ancient tkxinput because it was the only
>> device independent calibrator (it uses Xinput to read the coordinates). On
>> the other hand, I was impressed by the simplicity of the calibrator that
>> Soren Hauberg sent to this list in july (thread titled 'Evdev touchscreen
>> calibration?'), although it was written for usbtouchscreen driven devices
>> specifically.
>> I figured that a generic calibration program should be device independent
>> when reading calibration data, and device dependent in how to use the data.
>> I've adapted Soren's calibrator to do exactly this: it reads the current
>> calibration from Xinput. When the usbtouchscreen driver is used, it
>> dynamically changes the calibration. Otherwise it prints the new calibration
>> data in xorg.conf format on stdout. Other actions would be possible too,
>> like rewriting the xorg.conf directly, maybe even use some new evdev/Xinput2
>> goodness ?
> It's been quite a while since I was working on this (I changed job, so
> I never got to finish this), so my comments might not actually be
> true.
> First, I'd like to add that I'm glad you're spending time on
> resurecting my old code. Thanks :-)
> Second, part of this code was added before the 'evdev' X11 driver got
> support for touchscreens. This driver allows you to set the
> calibration parameters at run-time without making changes to xorg.conf
> (hence no restart of X). I think the calibration tool should use this
> instead of working with xorg.conf.

Wauw, it would be great to use this new 'evdev' functionality!
Where can I find out the details about this ? Or could somebody provide 
a code sample or something ?


More information about the xorg mailing list