Bug 199869

Summary:	Plasma cannot paint wallpaper in rgba since 4.3
Product:	[Unmaintained] plasma4	Reporter:	Nathanael Schilling <nathanaelschilling>
Component:	wallpaper-image	Assignee:	Plasma Bugs List <plasma-bugs>
Status:	RESOLVED UNMAINTAINED
Severity:	wishlist	CC:	asraniel, notmart, wearenotalone
Priority:	NOR
Version:	unspecified
Target Milestone:	---
Platform:	Ubuntu
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Attachments:	Adds an hidden option to set translucent background for desktopview (patch against kdebase-workspace-4.3.1) Adds an hidden option to set translucent background for desktopview (patch against trunk rev1027876) Adds an hidden option to set translucent background for desktopview (patch against kdebase-workspace-4.3.1)

Description Nathanael Schilling 2009-07-12 14:22:02 UTC

Version:           Plasma Workspace: 0.3 (using KDE 4.2.95)
OS:                Linux
Installed from:    Ubuntu Packages

In kde 4.1 and 4.2, it was possible to specify the wallpaper color to 0,0,0,0 in plasma-appletsrc which mean that plasma painted a transparent wallpaper. This made it possible to use an alternative application to plasma to paint the wallpaper. This was especially useful to compiz users because it meant they could use the "Wallpaper" plugin in Compiz to paint a separate wallpaper per viewport. In 4.1 and 4.2 (since trunk revision #786352) this worked very well (see http://forum.compiz-fusion.org/showthread.php?t=7519&page=1 for examples), but in 4.3 it is no longer possible, as setting the wallpaper color to 0,0,0,0 causes plasma to paint a black background. wallpaperrendederthread.cc in kdelibs/plasma/private/ still seems to use rgba which leads me to assume that the problem might be somewhere between reading the configuration files and actually rendering the wallpaper, though I could very well be wrong.

To Reproduce: 
1)startup plasma with a fresh configuration.
2) set the wallpaper to be a color, and use an arbitary color.
3) quit plasma
4) replace all recurrences of the color in the plasma config files with 0,0,0,0
5) start plasma and compiz
6)

Comment 1 Nathanael Schilling 2009-07-12 14:25:16 UTC

(Sorry, pressing space somehow submitted the bug even though I didn't finish the bug report)

6) load the Wallpaper plugin in compiz, and set multiple wallpapers.

Expected result : The Wallpaper drawn by compiz is seen
Actual result : The Wallpaper is not seen

Comment 2 WEARENOTALONE 2009-09-25 20:42:06 UTC

Hello,
after searching the whole day, but finally i found workaround and the reason for this bug. You have to revert this little patch: http://websvn.kde.org/?view=revision&revision=928340

At Debian Squeeze you can find this file in the kdebase-workspace-4.3.1 package under plasma/shells/desktop/desktopview.cpp (http://packages.debian.org/squeeze/kdebase-workspace-bin).

Please give me some feedback on this.

Sincerely yours,
WANA

Comment 3 Marco Martin 2009-09-27 19:39:59 UTC

setting the desktop window as ARGB makes plasma a bit slower, because triggers more copying around of pixmaps

Comment 4 WEARENOTALONE 2009-09-28 17:43:56 UTC

Maybe this could be implemented as an option in a configfile like the wallpapercolor=0,0,0,0 option (default: speed => no background transparency). Would the kde developers accept this?

Comment 5 Beat Wolf 2009-09-28 20:42:05 UTC

i suppose if you develop it as a hidden option that does not affect at all the rest of plasma, you have probably quite a good chance to get it accepted (and it should actually not be that hard to develop)

Comment 6 Nathanael Schilling 2009-09-29 18:50:49 UTC

I haven't looked at the actual code involved, but would it be (theoretically) possibly to integrate this into a plasma wallpaper plugin?

Comment 7 WEARENOTALONE 2009-10-01 18:35:31 UTC

Created attachment 37300 [details]
Adds an hidden option to set translucent background for desktopview (patch against kdebase-workspace-4.3.1)

Comment 8 WEARENOTALONE 2009-10-01 18:35:58 UTC

I implemented it as an hidden option named "translucentBackground" (because of Qt::WA_TranslucentBackground) in ~/.kde/share/config/plasma-desktoprc (example) :

...
[PlasmaViews][34]
DashboardContainment=0
translucentBackground=true
...

The default value of translucentBackground is false, because this is the default behavior at the moment. Attached to this comment are two patches, one against the Debian kdebase-workspace-4.3.1 source package and one against trunk (revision 1027876). The patch against kdebase-workspace-4.3.1 works fine for me, but the patch against trunk is untested!

Feel free to give me some constructive criticism :)

Best Regards,
WANA

Comment 9 WEARENOTALONE 2009-10-01 18:37:37 UTC

Created attachment 37301 [details]
Adds an hidden option to set translucent background for desktopview (patch against trunk rev1027876)

Comment 10 WEARENOTALONE 2009-10-01 18:38:21 UTC

Created attachment 37302 [details]
Adds an hidden option to set translucent background for desktopview (patch against kdebase-workspace-4.3.1)

Comment 11 Beat Wolf 2009-10-01 18:42:36 UTC

could you please submitt this patch on reviewboard.kde.org ? please also mention this bugnumber there.

Nice work by the way

Comment 12 Beat Wolf 2009-10-01 18:45:56 UTC

and i forgot, please mention if you have or don't have a svn account on reviewboard.

Comment 13 WEARENOTALONE 2009-10-01 20:11:18 UTC

You can find my review request here: http://reviewboard.kde.org/r/1755/

I just created a new regular account at reviewboard.kde.org, but i dont know if it is also a svn account (dont think so).

Comment 14 Nate Graham 2018-06-08 20:23:14 UTC

Hello!

This feature request was filed for KDE Plasma 4, which reached end-of-support status in August 2015. KDE Plasma 5's desktop shell has been almost completely rewritten for better performance and usability, so it is likely that this feature request is already implemented in Plasma 5, or is no longer applicable.

Accordingly, we hope you understand why we must close this feature request. If the requested feature is still desired but not implemented in KDE Plasma 5.12 or later, please feel free to open a new ticket in the "plasmashell" product after reading https://community.kde.org/Get_Involved/Bug_Reporting

If you would like to get involved in KDE's bug triaging effort so that future mass bug closes like this are less likely, please read https://community.kde.org/Get_Involved#Bug_Triaging

Thanks for your understanding!

Nate Graham