Bug 574182 - [GTK3] Label: Incorrect image drawing with 200% zoom
Summary: [GTK3] Label: Incorrect image drawing with 200% zoom
Status: NEW
Alias: None
Product: Platform
Classification: Eclipse Project
Component: SWT (show other bugs)
Version: 4.21   Edit
Hardware: PC Linux
: P3 critical (vote)
Target Milestone: ---   Edit
Assignee: Sravan Kumar Lakkimsetti CLA
QA Contact:
URL:
Whiteboard:
Keywords:
Depends on:
Blocks:
 
Reported: 2021-06-14 05:01 EDT by Thomas Singer CLA
Modified: 2021-08-19 08:59 EDT (History)
5 users (show)

See Also:

Attachments
Snippet to reproduce (783 bytes, text/plain)
2021-06-14 05:02 EDT, Thomas Singer CLA 		no flags Details
Screenshot from Manjaro (8.22 KB, image/png)
2021-06-14 05:02 EDT, Thomas Singer CLA 		no flags Details
Screenshot on Windows 10 (4.41 KB, image/png)
2021-06-14 05:03 EDT, Thomas Singer CLA 		no flags Details
Screenshot from Fedora 34 Wayland (319.88 KB, image/png)
2021-06-29 16:32 EDT, Soraphol (Paul) Damrongpiriyapong CLA 		no flags Details
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Description Thomas Singer CLA 2021-06-14 05:01:37 EDT 
Please launch the attached snippet on Linux (tried Ubuntu 20.04 and latest Manjaro/Gnome). I expect to see a cyan image drawn where the whole background is filled. But on Linux I see a black image drawn where the left upper quarter is just cyan.
Comment 1 Thomas Singer CLA 2021-06-14 05:02:18 EDT 
Created attachment 286590 [details]
Snippet to reproduce
Comment 2 Thomas Singer CLA 2021-06-14 05:02:45 EDT 
Created attachment 286591 [details]
Screenshot from Manjaro
Comment 3 Thomas Singer CLA 2021-06-14 05:03:56 EDT 
Created attachment 286592 [details]
Screenshot on Windows 10
Comment 4 Sravan Kumar Lakkimsetti CLA 2021-06-16 02:46:42 EDT 
I can reproduce this problem. I am investigating.
Comment 5 Sravan Kumar Lakkimsetti CLA 2021-06-16 05:55:30 EDT 
@paul, 

Can you please check whether you can reproduce this on RHEL/fedora/centos?

This is reproducible on Ubuntu. My feeling is some thing wrong with cairo libraries on Ubuntu.
Comment 6 Soraphol (Paul) Damrongpiriyapong CLA 2021-06-29 16:32:14 EDT 
Created attachment 286703 [details]
Screenshot from Fedora 34 Wayland

@Sravan

Sorry for the late reply. 

On Fedora 34 Wayland with scale set to 200% in the Displays setting, I don't experience the black rectangle around the cyan. Attached is a screenshot.
Comment 7 Sravan Kumar Lakkimsetti CLA 2021-07-01 08:43:52 EDT 
(In reply to Soraphol (Paul) Damrongpiriyapong from comment #6)
> Created attachment 286703 [details]
> Screenshot from Fedora 34 Wayland
> 
> @Sravan
> 
> Sorry for the late reply. 
> 
> On Fedora 34 Wayland with scale set to 200% in the Displays setting, I don't
> experience the black rectangle around the cyan. Attached is a screenshot.

That means its a problem with Ubuntu only.
Comment 8 Thomas Singer CLA 2021-07-01 09:24:06 EDT 
> That means its a problem with Ubuntu only.

It happens for Manjaro, too. But we need to use GDK_BACKEND=x11 to work around some other GTK bugs I have forgotten.
Comment 9 Alexander Kurtakov CLA 2021-08-17 14:16:27 EDT 
What are the wayland bug you workaround by falling back to x11?
Comment 10 Thomas Singer CLA 2021-08-19 08:59:07 EDT 
I don't know any more and haven't recorded it in our launcher script. I will remove the lines

if [ "$XDG_SESSION_TYPE" = "wayland" ]; then
	export GDK_BACKEND=x11
fi

and let you know what problems occur.