Wacom calibration results are off (wrong area)

[Tomas]

When I try to calibrate the touchscreen on my laptop (HP EliteBook 2760p, Wacom Serial Tablet WACf004) the result gets worse and worse with every calibration. The area on which the touchscreen is effective becomes smaller every time to the point where it is completely unusable.

This can be verified with "xsetwacom --get 15 area", right now this gives me "-9978 -6651 6336 -4878".
I can reset this by manually setting a new area, e.g. "xsetwacom --set 15 area 0 0 25000 16000"
However, xsetwacom only works for the current session, after a reboot all information is lost and the calibration is off again.

What should happen: the area for the touchscreen is improved with calibrating
What happens instead: the area gets smaller for every calibration

I'd be happy to contribute a bit in fixing this bug, but my knowledge is limited.

Meanwhile, I'd appreciate a workaround: how can I reset the area used for the touchscreen to the default?

ProblemType: Bug
DistroRelease: Ubuntu 13.04
Package: gnome-control-center 1:3.6.3-0ubuntu18
ProcVersionSignature: Ubuntu 3.8.0-13.23-generic 3.8.3
Uname: Linux 3.8.0-13-generic x86_64
ApportVersion: 2.9.2-0ubuntu5
Architecture: amd64
Date: Tue Apr 2 14:19:57 2013
InstallationDate: Installed on 2013-03-20 (12 days ago)
InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Alpha amd64 (20130319)
MarkForUpload: True
SourcePackage: gnome-control-center
UpgradeStatus: No upgrade log present (probably fresh install)
usr_lib_gnome-control-center:
 activity-log-manager-control-center 0.9.4-0ubuntu6.1
 deja-dup 26.0-0ubuntu1
 gnome-control-center-signon 0.1.5-0ubuntu1
 gnome-control-center-unity 1.2daily13.04.01-0ubuntu1
 indicator-datetime 12.10.3daily13.03.07-0ubuntu1

[Tomas (tomasvandenooijevaer)]

Note that "xinput_calibrator" is a bit more verbose and warns me:

Warning: multiple calibratable devices found, calibrating last one (Serial Wacom Tablet touch)
 use --device to select another one.
Calibrating standard Xorg driver "Serial Wacom Tablet touch"
 current calibration values: min_x=0, max_x=2640 and min_y=0, max_y=1630

With the default settings, it gives me a very wrong result resulting in a similar area as reported.

By using "xinput_calibrator --device 15" I get proper values: "-1232 -523 26217 16525".

My best guess is that the Wacom calibration through the control centre is using the wrong input device.

[Tomas (tomasvandenooijevaer)]

Workaround (until display configuration is changed):

xsetwacom --set "Serial Wacom Tablet stylus" ResetArea
xsetwacom --set "Serial Wacom Tablet eraser" ResetArea

Keen to hear about "permanent workaround": how to access/reset the values stored by the Wacom calibration tool.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Josh Berry (taeric)]

Looks like if you want to save the settings stored by the calibration tool, you simply need to use the dconf tool and search for "wacom." One of the items directly under "wacom" has the key of area. Simply set that to what you would get with:

    xsetwacom --get "..." area

I am more than interested in trying to dig into the code. I believe I have it checked out correctly, though I am not clear on the process for testing my changes. Has this already been solved by anyone else?

[Tomas (tomasvandenooijevaer)]

Well, that was easy. I indeed can just search for wacom in dconf and change the "area" key value. This is of course a much nicer workaround than above, it still works after rebooting. I only used gconf, with which I couldn't find this key.
The key is in org > gnome > settings-daemon > peripherals > wacom > (very long string).

AFAIK this bug has not been fixed or attempted by anyone else.

Best of luck with fixing this Josh, and thanks for supplying us with a decent workaround. Please let me know if you need any testing done, I'd be happy to help!

[Sebastien Bacher (seb128)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. The issue you are reporting is an upstream one and it would be nice if somebody having it could send the bug to the developers of the software by following the instructions at https://wiki.ubuntu.com/Bugs/Upstream/GNOME. If you have done so, please tell us the number of the upstream bug (or the link), so we can add a bugwatch that will inform us about its status. Thanks in advance.

[Josh Berry (taeric)]

I am going to be away from a net connection most of today. A quick search upstream does not show anything regarding this. Will get the required accounts created and bugs enterred when I get a chance this evening.

[Josh Berry (taeric)]

So, I put in more time than I'd care to admit getting the gnome source compiling so I could test this. It appears the latest version does not have this issue, though I could not find a bug directly related to this. I sent an email to the gnomecc-list asking if this was a known issue, if there was a way I could verify it was an issue with the old version, and if there was a bug this was directly related to. Will update here when I hear back.

[Josh Berry (taeric)]

One oddball update on this. The last few times I have tried the calibration in the settings menu, it has actually worked correctly.

[Josh Berry (taeric)]

Just checking to see if the calibration is still off for anyone else. As noted, it seems to be working as desired for me, now. My hunch is that something has changed the default list of my devices such that the Touch device is the middle one. The end device is now my Eraser device. As such, even if it is picked for calibration, I'll get the correct data.

[Tomas (tomasvandenooijevaer)]

Hi Josh et al. Testing the calibration before your workaround didn't yield proper results, it was still way off. After entering a reasonable value in dconf and recalibrating it indeed seems to calibrate my pen instead of touch, resulting in a nicely calibrated screen.
Sorry about not realising this earlier. As far as I'm considered this bug is fixed.

[Josh Berry (taeric)]

Not your fault for missing it. I had assumed I made a change on my end when installing the gnome source that got things working. I will try this on a live image to see if it is somehow based on the values in conf. Could be that the issue still exists in the latest source, actually. Probably won't get a chance to do this till later this week, though. Any chance you have example bad values handy?

[Tomas (tomasvandenooijevaer)]

If my configuration is already very wrong, I cannot fix it by calibrating via the GUI in "Wacom Tablet". For example, try setting the "area" string in dconf to:
[-9978, -6651, 6336, 4878]

For me, the first calibration claims success but does not set the values to something reasonable. The string "area" reads after this calibration:
[2814, 1669, 6824, 5319]
Using the pen to click anywhere the cursor always moves to the bottom left corner.

If I try to calibrate again I get a "Misclick detected" error and need to start over.

Note that manually fixing the settings via the workaround as Josh suggests in post #5 and I further explain in #6 and then calibrating yields a working area for me:
[54, 91, 26082, 16359]

[Josh Berry (taeric)]

There is a bug in gnome's bugzilla now. https://bugzilla.gnome.org/show_bug.cgi?id=703783

Apologies if I am entering this incorrectly.

[Sebastien Bacher (seb128)]

> There is a bug in gnome's bugzilla now. https://bugzilla.gnome.org/show_bug.cgi?id=703783

thanks