The Linux Wacom Project
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Linux Wacom Project HOWTO
11.0 - Tablet-Screen Mapping
This page explains how multi-monitor settings are supported and how to use the InputDevices options to setup your desired tablet-to-screen mapping for some of the settings.
Linux Wacom X driver (wacom_drv.so) mainly supports four types of dual/multi-monitor setup in use with X server on Linux: TwinView, Xinerama, Xrandr, as well as non-TwinView and non-Xinerama case, where you normally can move the cursor from one screen to the other, but you can not move an application window, such as a terminal, from one screen to the other.
By TwinView setup, we used to represent the two screens are configured in such a way that X "thinks" it only has one screen. Starting from release 0.8.3-6, we added the non-TwinVew setup for nvidia card as TwinView with option Xinerama. So, it is getting more confused even among us, the developers. Thanks for the new dual display support from Nvidia driver.
There are four kinds of tablet-to-screen mappings in this setup:
1. map the tablet to the whole desktop;
In this case, there is no extra option required in the InputDevices section for Wacom driver in your X11's configuration file. So this is the default state for TwinView setup.
2. map the tablet to one screen at a time when dual display is in TwinView setup, but can switch screens at wish;
Option "TwinView" is used in the InputDevices section of the X11's configuration file to configure Wacom driver.
This feature was initially supported by Dreamwork developers. Their idea was to maximize the accuracy of the tablet on one screen and be able to move the cursor between screens without issuing a command (such as xsetwacom) or press a button (such as display toggle). The tradeoff is that you lost about 60 tablet count of points on the side that enables the screen switch.
3. map the tablet to a specific screen when dual display is in TwinView setup.
Option "TwinView", "TVResolution0", "TVResolution1", and "ScreenNo" are used in the InputDevices section of the X11's configuration file to configure Wacom driver . Detailed use of these options can be found by "man wacom".
4. map the tablet to a specific screen when dual display is in non-TwinView setup with Nvidia card.
Option "TwinView" and "ScreenNo" are used in the InputDevices section of the X11's configuration file to configure Wacom driver. The screen resolution is retrieved from the X server the same way as we retrieve it for an Xinerama setup. The actual option in the InputDevice section would be:
Option "TwinView" "Xinerama"
Option "ScreenNo" "theScreenNumber"
I've seen displays with Xinerama in their xorg.conf files in fact fall into TwinView setup since the whole desktop is reported as one screen. Use xsetwacom get stylus NumScreen to see how many screen you have. You need to use this command without adding any screen mapping related options in your xorg.conf file for Wacom device. If the command only reports one screen but you actually have two screen on the system, you are running a TwinView setup. If it reports more than one screen, you are in Xinerama setup.
1. map the tablet to the whole desktop;
No extra option required in the InputDevices section for Wacom driver in your X11's configuration file to support this setup. It is the default state.
2. map the tablet to one screen at a time, but can switch screens with the regular mouse or a user defined button/app;
Option "MMonitor" "off" is used in the InputDevices section of the X11's configuration file to configure Wacom driver. The cursor will stay in the screen where you started to use the configured Wacom device. You can change screens by moving the cursor with another device/app, such as system mouse or another Wacom device which is not configured with "MMonitor" "off", then use the configured Wacom device in that screen.
3. map the tablet to a specific screen.
Only option "ScreenNo" is needed to configure Wacom driver in this setting.
non-TwinView and non-Xinerama setup
In this setup, we only support tablet to a specific screen mapping, that is, you have to map the tablet to a specific screen by option "ScreenNo". Otherwise, your tablet may be mapped half on the first screen and the other half on the second screen.
X11 InputDevices Options details all options for your Wacom device that we mentioned above.
This support is provided by Novell developers. A daemon called wacomxrrd is added to src/util to map Wacom LCD tablet to its own screen under extended RandR mode. The daemon can be launched by "wacomxrrd $dev" and managed through your prefered desktop interfaces.
On SLED 11, it is done by adding the following script, wacomxrrd-start, to /usr/bin
#!/bin/sh grep -q -i wacf /sys/bus/pnp/devices/*/id && exec wacomxrrd -i touch exit 0and putting wacomxrrd.desktop to /usr/share/gnome/autostart.