Bug 512616

Summary: Anti-aliasing works only on display where Okular was opened
Product: [Applications] okular Reporter: WURMi <wurmi>
Component: PDF backendAssignee: Okular developers <okular-devel>
Status: REPORTED ---    
Severity: normal    
Priority: NOR    
Version First Reported In: 25.08.3   
Target Milestone: ---   
Platform: Fedora RPMs   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: example of anti-aliasing issue

Description WURMi 2025-11-25 22:26:10 UTC
Created attachment 187176 [details]
example of anti-aliasing issue

SUMMARY

I have 3-display setup:

1. 1920x1200 (100% scale)
2. 2560x1440 (120% scale)
3. 1680x1050 (105% scale)
(scales ale different to preserve the same visual size of an application on all displays)

When I open Okular and open random PDF document e.g. on second display, everything is OK. But when I move the window to first or third display, anti-aliasing is not applied and fonts are pixelated. When I move window back to second display, everything is OK again.

STEPS TO REPRODUCE
1. open PDF document in Okular
2. move window to different display with different scaling


OBSERVED RESULT
font is poorly readable and pixelated

EXPECTED RESULT
font should be anti-aliased

SOFTWARE/OS VERSIONS
System: Fedora KDE 43
Kernel: Linux 6.17.7-300.fc43.x86_64
DE: KDE Plasma 6.5.2

ADDITIONAL INFORMATION
I found a workaround by changing the Zoom factor. Document is forced to redraw and anti-aliasing is applied. Maybe this redraw function should be called even when window is moved from one display to another to reapply the anti-aliasing