Bug 462340

Summary: The content in Kolourpaint should NOT be scaled with DPI setting
Product: [Applications] kolourpaint Reporter: pikakolendo02
Component: generalAssignee: kolourpaint-support
Status: RESOLVED DUPLICATE    
Severity: normal CC: wks1986
Priority: NOR    
Version: 22.08.3   
Target Milestone: ---   
Platform: Other   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:
Attachments: The content is scaled even if Kolourpaint is at 100%
KolourPaint at 150% display scale

Description pikakolendo02 2022-11-28 05:15:34 UTC
Created attachment 154097 [details]
The content is scaled even if Kolourpaint is at 100%

The content in Kolourpaint should NOT be scaled with DPI setting


STEPS TO REPRODUCE
1. set global DPI scale to 125%
2. paste any screenshot in Kolourpaint

OBSERVED RESULT
The content will be scaled even if Kolourpaint is at 100%

EXPECTED RESULT
The content in Kolourpaint should NOT be scaled, just like what the graph shows in Gwenview at 100%

SOFTWARE/OS VERSIONS

Linux/KDE Plasma: Arch Linux 6.0.10
KDE Plasma Version: 5.26.3
KDE Frameworks Version: 5.100.0
Qt Version: 5.15.7

ADDITIONAL INFORMATION
Comment 1 Kunshan Wang 2024-03-11 03:27:32 UTC
Created attachment 166931 [details]
KolourPaint at 150% display scale

This problem still persists after upgrading to KDE 6.

Scaling makes most applications look better, but graphics applications like KolourPaint should not scale the image it is editing.

I added a screenshot.  I set the "Scale" in "Display & Monitor" in "System Settings" to 150%.  I confirmed that KRuler measures the actual number of pixels on the screen (my screen is 2560x1600).  I set the image size of the content in KolourPaint to 640x480, and KRuler shows that it is actually 960 pixels wide on the screen.

This behaviour is problematic.  For example,  I can no longer draw a sharp one-pixel line.  I can't inspect any given image in a pixel-accurate way as it will always be scaled.

Operating System: Arch Linux 
KDE Plasma Version: 6.0.1
KDE Frameworks Version: 6.0.0
Qt Version: 6.6.2
Kernel Version: 6.7.9-arch1-1 (64-bit)
Graphics Platform: Wayland
Comment 2 Christoph Feck 2024-07-31 20:07:49 UTC

*** This bug has been marked as a duplicate of bug 436615 ***