Touchscreens (mutouch) & multiple heads

[Peter Hutterer]

On Fri, Apr 15, 2011 at 12:11:09PM -0400, Michael Smith wrote:
> Hi,
> 
> I have an Intel 915GM with two heads, each 800x600. One head feeds a
> touchscreen using the mutouch driver. Touchscreen input is being
> scaled by the total screen dimensions (1600x600), rather than just
> the 800x600 part of the display that is connected to the
> touchscreen.
> 
> In the past I would have hacked up the mutouch driver to add
> overrides for ScreenWidth and ScreenHeight. I understand the X
> server now handles conversion of raw coordinates (in
> dix/getevents.c?), and the mutouch conversion_proc is no longer
> called.
> 
> Where is the right place to add a way to override the screen width
> used for converting raw coordinates? Or is there already a way to do
> this?

http://www.x.org/wiki/XInputCoordinateTransformationMatrixUsage
run-time only though

Cheers,
  Peter
> 
> Section "InputDevice"
>         Identifier "touchscreen_serial"
>         Driver "mutouch"
>         Option "Device" "/dev/ttyS1"
>         Option "BaudRate" "2400"
>         Option "InputFashion" "Touchpanel"
> 
>         Option "DebugLevel" "9"
>         Option "ScreenNo" "0"
>         Option "MinX" "0"
>         Option "MaxX" "16350"
>         Option "MinY" "16350"
>         Option "MaxY" "525"
> 
>         Option "Name" "MUTOUCH:TOUCHSCREEN"
>         Option "ReportingMode" "Scaled"
>         Option "SendCoreEvents" "on"
>         Option "Type" "Finger"
> EndSection
> 
> Thanks!
> Mike