multiscreen spanning wallpaper does not span on lock screen

[Rachel Greenham]

(It has same look as unity-greeter in lightdm but am given to believe lock screen is handled by gnome-screensaver; move if i'm wrong! lightdm seems to get it wrong a different way.)

If, having made a wide wallpaper to span multiple monitors, and having set it as your wallpaper with type "Span" in Appearance settings, you then go to the new "Lock" screen...

... you will see that instead of that wide wallpaper spanning all monitors, you get the image scaled down to be shown whole on *each* monitor. As shown in screenshot attached.

It needs to honour the appearance settings in this regard.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: gnome-screensaver 3.6.1-0ubuntu10
ProcVersionSignature: Ubuntu 3.13.0-17.37-generic 3.13.6
Uname: Linux 3.13.0-17-generic x86_64
ApportVersion: 2.13.3-0ubuntu1
Architecture: amd64
CurrentDesktop: Unity
Date: Wed Mar 12 13:02:42 2014
GnomeSessionIdleInhibited: No
GnomeSessionInhibitors: None
GsettingsGnomeSession:
 org.gnome.desktop.session session-name 'ubuntu'
 org.gnome.desktop.session idle-delay uint32 300
InstallationDate: Installed on 2014-03-08 (3 days ago)
InstallationMedia: Ubuntu 13.10 "Saucy Salamander" - Release amd64 (20131016.1)
SourcePackage: gnome-screensaver
UpgradeStatus: Upgraded to trusty on 2014-03-10 (1 days ago)

[Launchpad Janitor (janitor)]

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

[Raito Akehanareru (raito-akehanareru)]

Any updates?

I'm also sad when I lock my computer at work and i have "two" wallpapers instead of one.

[Jonathan Harker (jonathanharker)]

PONIES!!!

[Alex Corrie (electrichead)]

As far as I can see the lockscreen is the responsibility of the 'unity' package as of 14.04.

Not sure what the etiquette of changing this is, but I'm not sure it makes sense to make a new report.

[Alex Corrie (electrichead)]

Some additional information:

The lockscreen does respect other settings in in the "org.gnome.desktop.background" gsettings schema, namely the primary-color key. The default is a nice bright blue and really accentuates the primarily black/dark, zoomed background images ;)

My workaround:

$ gsettings set org.gnome.desktop.background primary-color '#000000'

[Sullivan Senechal (soullivaneuh)]

Same problem on Ubuntu 14.10.

Any news about a fix?

Thanks.

[Max Rumpf (maxr1998)]

Still happening on Ubuntu 15.04. Please fix, it doesn't look very nice..

[Alex Baggott (alex-baggott)]

As part of the big bug review for 16.04 LTS I have tested this on 15.10 and the bug is still there.

[Lifepower (yunkot)]

This issue is still present in Ubuntu 16.04.

[Chad Blackmon (chadb4184)]

Confirmed this issue is still present in Ubuntu 16.04.

[Henry (hvanmegen)]

I say we need to start a bounty system to get these bugs fixed.. maybe even add some cryptocurrency or old-school money towards it...

[Forrest Voight (forrestv)]

I've fixed this bug in the attached patches. The first solves the problem with minimal changes, but is inefficient as it computes the entire (multi-monitor) wallpaper once per monitor rather than computing it just once, resulting in an added delay of a second or two with a large multimonitor setup. The second patch fixes that inefficiency, but touches a lot more of the code.

To apply this patch to your 16.04 system:

    mkdir work && cd work
    # get second.diff and put it here
    sudo apt build-dep unity
    apt source unity
    cd unity-7.4.0+16.04.20160906/
    patch -i ../second.diff -p1
    DEB_BUILD_OPTIONS="nocheck" dpkg-buildpackage -us -uc -nc -j10
    sudo dpkg -i ../*.deb

Henry/others: If you're feeling like a retroactive bounty, my Bitcoin address is on http://forre.st/

[Forrest Voight (forrestv)]

Ah, after running those commands just run "unity" to replace the running unity with the patched one. No reboot or log out/in necessary.

[Ubuntu Foundations Team Bug Bot (crichton)]

The attachment "first.diff" seems to be a patch. If it isn't, please remove the "patch" flag from the attachment, remove the "patch" tag, and if you are a member of the ~ubuntu-reviewers, unsubscribe the team.

[This is an automated message performed by a Launchpad user owned by ~brian-murray, for any issues please contact him.]

[Tobias Lindström (tobias-lindstrom)]

Tried the patch and it works, I had to restart the machine thou. Just running "unity" caused my browser and some other windows to display empty gray boxes. But after a reboot all was back to normal.

Thanks Forrest!

[Khurshid Alam (khurshid-alam)]

@Forrest Voight

Thanks for working on the issue. Is it still reproducible in 18.04? If so, can you also provide a patch for 18.04 (currently in development)? If it works we can make a merge request.

[bi (beez)]

@Forrest Voight

Thanks for working on it, but is there any way you can provide a patch for unity_7.4.5+16.04.20180221 for my system? Trying to apply either patch isn't completely compatible with the newer version. Would really appreciate it!

Thank you in advance!!!

[o2122660 (o2122660)]

On Ubuntu 18.04.1 a multiscreen screen lock wallpaper works using Tweaks (gnome-tweak-tool). Open Tweaks and in the Appearance tab in the Lock Screen section, select your multiscreen wallpaper as the Image and set the Adjustment to Wallpaper.