Bizarre Wacom mouse behaviour on Dual Head display

iainr · 10-02-2009, 01:07 AM

I've a shiny new computer with Ubuntu 9.04, an Nvidia graphics card (GeoForce 9400 GT) and two monitors, along with a Wacom Intuos3 graphics tablet. The goal: a dual-head setup where the monitors are used as one big screen.

It didn't work with the free drivers, so I installed the proprietary nvidia driver. Set it up inside a few minutes and it worked perfectly - brilliant.

A couple of days later, I reboot the PC and when it comes back up, it's not working (back to only using one display).

OK, so the changes didn't get saved in xorg.conf. Go through the nvidia configuration tool and, although the save comes up with an error (permissions, I guess), I can preview the xorg.conf file and cut-and-paste it in.

I don't seem to be able to get it working quite as it was before (when I'm sure it had two virtual screens), but the config below looks OK with xinerama enabled and one virtual machine. The desktop looks the way I want it to.

Code:

# xorg.conf (X.Org X Window System server configuration file)
#
# This file was generated by dexconf, the Debian X Configuration tool, using
# values from the debconf database.
#
# Edit this file with caution, and see the xorg.conf manual page.
# (Type "man xorg.conf" at the shell prompt.)
#
# This file is automatically updated on xserver-xorg package upgrades *only*
# if it has not been modified since the last upgrade of the xserver-xorg
# package.
#
# Note that some configuration settings that could be done previously
# in this file, now are automatically configured by the server and settings
# here are ignored.
#
# If you have edited this file but would like it to be automatically updated
# again, run the following command:
#   sudo dpkg-reconfigure -phigh xserver-xorg

# nvidia-settings: X configuration file generated by nvidia-settings
# nvidia-settings:  version 1.0  (buildd@palmer)  Sun Feb  1 20:21:04 UTC 2009

# xorg.conf (X.Org X Window System server configuration file)
#
# This file was generated by dexconf, the Debian X Configuration tool, using
# values from the debconf database.
#
# Edit this file with caution, and see the xorg.conf manual page.
# (Type "man xorg.conf" at the shell prompt.)
#
# This file is automatically updated on xserver-xorg package upgrades *only*
# if it has not been modified since the last upgrade of the xserver-xorg
# package.
#
# Note that some configuration settings that could be done previously
# in this file, now are automatically configured by the server and settings
# here are ignored.
#
# If you have edited this file but would like it to be automatically updated
# again, run the following command:
#   sudo dpkg-reconfigure -phigh xserver-xorg

Section "ServerLayout"
    Identifier     "Default Layout"
    Screen      0  "Screen0" 0 0
    Screen      1  "Screen1" RightOf "Screen0"
    InputDevice    "Keyboard0" "CoreKeyboard"
    InputDevice    "Mouse0" "CorePointer"
EndSection

Section "Module"
    Load           "glx"
EndSection

Section "ServerFlags"
    Option         "Xinerama" "1"
EndSection

Section "InputDevice"
    # generated from default
    Identifier     "Keyboard0"
    Driver         "kbd"
EndSection

Section "InputDevice"
    # generated from default
    Identifier     "Mouse0"
    Driver         "mouse"
    Option         "Protocol" "auto"
    Option         "Device" "/dev/psaux"
    Option         "Emulate3Buttons" "no"
    Option         "ZAxisMapping" "4 5"
EndSection

Section "Monitor"
    Identifier     "Configured Monitor"
EndSection

Section "Monitor"
    Identifier     "Monitor0"
    VendorName     "Unknown"
    ModelName      "INL LE-1708"
    HorizSync       24.0 - 82.0
    VertRefresh     55.0 - 77.0
EndSection

Section "Monitor"
    Identifier     "Monitor1"
    VendorName     "Unknown"
    ModelName      "Acer P193W"
    HorizSync       30.0 - 81.0
    VertRefresh     55.0 - 76.0
EndSection

Section "Device"
    Identifier     "Configured Video Device"
    Driver         "nvidia"
    Option         "NoLogo" "True"
EndSection

Section "Device"
    Identifier     "Device0"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BoardName      "GeForce 9400 GT"
    BusID          "PCI:1:0:0"
    Screen          0
EndSection

Section "Device"
    Identifier     "Device1"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BoardName      "GeForce 9400 GT"
    BusID          "PCI:1:0:0"
    Screen          1
EndSection

Section "Screen"
    Identifier     "Default Screen"
    Device         "Configured Video Device"
    Monitor        "Configured Monitor"
    DefaultDepth    24
EndSection

Section "Screen"
    Identifier     "Screen0"
    Device         "Device0"
    Monitor        "Monitor0"
    DefaultDepth    24
    Option         "TwinView" "0"
    Option         "TwinViewXineramaInfoOrder" "CRT-0"
    Option         "metamodes" "CRT-0: nvidia-auto-select +0+0"
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection

Section "Screen"
    Identifier     "Screen1"
    Device         "Device1"
    Monitor        "Monitor1"
    DefaultDepth    24
    Option         "TwinView" "0"
    Option         "metamodes" "CRT-1: 1440x900 +0+0"
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection

But the Wacom tablet, which worked perfectly at the start with no tweaking, is now doing something very odd.

I can move a window between the two screens - there and back.

But if I use the Wacom mouse, it can move from the left to the right screen, but then gets stuck on the right. The mouse pointer won't won't go back to the left screen whatever I try.

If I switch to the Wacom pen, it will move the mouse pointer between screens, but will only move it on the outside of the two screens (so with the pen I can move the pointer around the right half of the right-hand screen and the left half of the left-hand screen, but it jumps between the two and I can't get it to the middle section at all).

By switching between mouse and pen I can sort of control it: the mouse will move the pointer anywhere in a screen, and from left to right, and I can use the pointer to move it from right to left.

But this isn't how it's meant to be, and it isn't how it was two days ago when I did no special configuration at all - the wacom tablet just worked.

iainr · 10-02-2009, 01:40 AM

Not for the first time, having spent hours failing to solve a problem, I crack it within minutes of posting.

Although I was sure I'd tried it before, using the Nvidia TwinView feature did the trick, with both wacom tablet and screens behaving, including after reboot.

In addition to selecting twinview, I temporarily changed the perms on /etc/X11/* so the nvidia app launched under my user ID was able to save changes to xorg.conf.

Note: When I first selected the Twinview option and clicked the "Apply" button on the Nvidia X Server settings app, it came up with an error. Saving to xorg.conf and logging out still worked fine. though.