Bug 432811

Summary: Add some smoothing for window thumbnails
Product: [Plasma] kwin Reporter: Daniel <daniel-other+kdebug>
Component: effects-present-windowsAssignee: Daniel <daniel-other+kdebug>
Status: RESOLVED INTENTIONAL    
Severity: wishlist CC: kde, nate
Priority: NOR    
Version: 5.20.5   
Target Milestone: ---   
Platform: Arch Linux   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:
Attachments: A screenshot of a window in Present-Windows: Text in the window looks pixely and ugly.
output of qdbus org.kde.KWin /KWin org.kde.KWin.supportInformation

Description Daniel 2021-02-11 18:49:30 UTC
Created attachment 135599 [details]
A screenshot of a window in Present-Windows: Text in the window looks pixely and ugly.

SUMMARY
Currently, when using the Present-Windows function the actual windows look a bit strange, because the full resolution of the window is reduced to a very small size. This makes text look strange and "pixely". A bit of blur on the windows would make the appearance much smoother and elegant. See screenshot for an example.

STEPS TO REPRODUCE
1. Open Present-Windows

OBSERVED RESULT
The windows look "pixely" because they are scaled without blur applied.

EXPECTED RESULT
A little bit of blur (maybe depending on screen resolution and window size?) would make it look smoother and better.
Comment 1 David Edmundson 2021-06-19 15:09:16 UTC
That isn't how things normally look.

It implies the lanczos filter was disabled, which is something that happens when we detect poor hardware. Can you confirm output of:  

qdbus org.kde.KWin /KWin org.kde.KWin.supportInformation
Comment 2 Daniel 2021-06-19 15:28:27 UTC
Created attachment 139518 [details]
output of qdbus org.kde.KWin /KWin org.kde.KWin.supportInformation

The machine is a Lenovo Thinkpad X1 Yoga 4th Generation from 2019, so it should be powerful enough ;)
Comment 3 David Edmundson 2021-06-19 20:47:21 UTC
>glSmoothScale: 0

aha.

Can you go to system settings -> compositor -> scale method  and confirm it says "accurate"
Comment 4 Daniel 2021-06-19 20:56:16 UTC
Ah, indeed it was set to pixely. With it set to accurate, the present-window thing looks much better!