Bug 347610

Summary:	Wallpaper scaling/positioning incorrect: wrong size and/or blurry
Product:	[Plasma] plasmashell	Reporter:	Soukyuu <chrno-sphered>
Component:	Image & Slideshow wallpaper plugins	Assignee:	Marco Martin <notmart>
Status:	RESOLVED FIXED
Severity:	minor	CC:	finex, Flupp+bugs.kde.org, godlike64, kde, nate, plasma-bugs-null
Priority:	NOR
Version First Reported In:	5.3.0
Target Milestone:	1.0
Platform:	Arch Linux
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:
Attachments:	an example of a blurry wallpaper on the right when using "scaled and cropped" for comparison: manually cut wallpaper on the right monitor

Description Soukyuu 2015-05-12 13:49:10 UTC

This used to work correctly in KDE4. Most positioning modes are affected. My second monitor has a resolution of 1280x1024 and I'm using a 1920x1080 wallpaper.



Reproducible: Always

Steps to Reproduce:
1. choose wallpaper with width > monitor res width and height < monitor res height
2. choose a positioning mode
3. apply

Actual Results:  
- "scaled and cropped": image is very blurry.
- "scaled": image is slightly blurry
- "scaled, keep proportions" works fine
- "centered" works as "scaled, keep proportions"
- "tiled" woks as "scaled, keep proportions"

Expected Results:  
- "scaled and cropped": image should not be blurry
- "scaled": image should not be blurry
- "scaled, keep proportions" works fine
- "centered" should be closer to "scaled and cropped"
- "tiled" should start in the upper left corner

Running stable packages of arch linux, so at 5.3.0-3 atm. 
Workaround: resize the wallpaper yourself.

Comment 1 Soukyuu 2015-05-12 14:03:49 UTC

Created attachment 92558 [details]
an example of a blurry wallpaper on the right when using "scaled and cropped"

Note how the big bird appears blurry compared to the one on the left.

Comment 2 Soukyuu 2015-05-12 14:08:32 UTC

Created attachment 92559 [details]
for comparison: manually cut wallpaper on the right monitor

This is manually cutting the image. Since the wallpaper is bigger than the monitor resolution, no resize is needed. This is also how it looked on KDE4 and how it looks on windows.

Comment 3 Flupp 2015-05-15 11:05:54 UTC

this seems to be a duplicate of #338506

Comment 4 Soukyuu 2015-05-15 14:22:49 UTC

Partially. The other bug does not describe problems with "centered" and "tiled" modes, otherwise it's the same, yeah.

Also, it looks like my math failed me. It should have been "wallpaper height > monitor height" not "< monitor height". Which means that centered should not have any black bars at all - the wallpaper is bigger than the monitor!

Comment 5 godlike 2015-08-25 14:58:33 UTC

This also happens to me under current KDE (installed applications-15.08 on Gentoo, bringing in latest KF5/Plasma versions). I have a 4 monitor setup wherein two of them are rotated 90° (1080x1920). The 1920x1080 wallpapers on these used to display fine on KDE4 (only a part of the wallpaper was displayed on "Scaled & cropped", but no blur). On KDE 5, they are displayed with a high level of blur (more noticeable, at least in person, than the attachments here). I can upload an attachment when I get home for comparison, but I believe it could be related to how much difference there is between wallpaper and monitor dimensions.

Comment 6 godlike 2015-11-11 16:30:49 UTC

I don't know which one of the two bugs (this one or #338506) is the right one. Since the other one is the CONFIRMED one, I uploaded there a screenshot of my desktop + the wallpaper I'm using, so the blurryness can be seen more clearly (pun intended).

Comment 7 FiNeX 2016-05-19 13:15:34 UTC

Hi, I can confirm the bug using the latest plasma-desktop 5.6.4.

Comment 8 Nate Graham 2019-06-14 22:33:25 UTC

This has since been fixed. I think it was in 5.9 or 5.10.