Touchscreen + Twinview

[Guest]

Hi,

running my HTPC with a Beamer, I thought that it might be a good idea to attach a touchscreen for some music playing only without turning on the beamer.

Touchscreen is supported by the evtouch driver and everything is working fine, except the fact that the touchscreen itself is mapped to the whole screen--including the beamer... Calibrating the touchscreen produces a new instance of the file /etc/evtouch/config containing the calibration data, for example

MINX="96"
MINY="156"
MAXX="1913"
MAXY="1866"
X0="-12"
Y0="-3"
X1="-48"
Y1="5"
X2="-3"
Y2="1"
X3="5"
Y3="28"
X4="-39"
Y4="-9"
X5="-1"
Y5="-29"
X6="5"
Y6="-2"
X7="7"
Y7="-2"
X8="-5"
Y8="3"

I thought about "hacking" these values but that was not successful, it only led to funny mouse actions... I actually do not understand these values completely, OK we have some minima and maxima and the 9 calibration points. Are the later relative to the positions the point should be?
Does anyone know about further/"hidden" options of the evtouch driver to map the area of the touchscreen to pixel coordinates? Any other ideas?

BTW evtouch driver is 0.8.8 which should be the current version I think.

Thanks,
joko