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UTD User Manual
evaluated and assembled into one large commandline by
/etc/init.d/wntouch start
on system boot time.
Mapping Tool
In order to allow automatic configuration changes and mappings of newly
attached devices, the wnmapping tool is called by udev each time a new
supported device is detected. Additionally, the wntouch daemon gets to
re-enumerate its devices by receiving signal 1 (SIGHUP) from wnmapping,
when called by udev. In the reverse scenario, whenever wntouch needs to
refresh its emulated device list, wnmapping will be called with options
--
wntouch
and
--disable
, so only the wntouch devices are attached to
screens by Xorg, and the original “raw” devices are detached from the in-
put queue in order to avoid conflicting mouse/touch protocol data.
Calibration Tool
In order to allow calibration, the wntouch driver exposes a calibration
interface through a socket for each device discovered located in
/var/run/wn/wntouch/wncalibX
.
Access rights to the calibration interface can be controlled by setting the
desired access rights to these special files.
The calibration tool wncalibrate will use these sockets to communicate
with the driver and set new calibration data. Once opened the wntouch
driver will send all incoming events to the calibration socket unfiltered in-
stead of sending them to the output event device. wncalibrate will use the
data to calculate a new calibration and will send this new data to the
wntouch driver using the following commands:
> CALIBRATE <min_x> <max_x> <min_y> <max_y>
> SCREEN_DATA <x> <width> <y> <height>
> DESKTOP_DATA <x> <width> < y> <height>
Once new calibration data is sent, the wntouch driver will generate output
events again using this calibration data. In order to persist the new calibra-
tion data the wncalibrate tool needs to send the following command:
> SAVE
