| Summary: | Panel and applets still apply background blur even when panel set to opaque | ||
|---|---|---|---|
| Product: | [Plasma] kwin | Reporter: | Tech-Tac <im.tech.tac> |
| Component: | effects-various | Assignee: | KWin default assignee <kwin-bugs-null> |
| Status: | RESOLVED INTENTIONAL | ||
| Severity: | normal | CC: | nate, niccolo.venerandi |
| Priority: | NOR | ||
| Version First Reported In: | 6.4.3 | ||
| Target Milestone: | --- | ||
| Platform: | Other | ||
| OS: | Linux | ||
| Latest Commit: | Version Fixed/Implemented In: | ||
| Sentry Crash Report: | |||
| Attachments: | Blur on supposedly opaque app launcher | ||
Can you reproduce this issue in a new clean user account with no customizations? Yes Created attachment 183890 [details]
Blur on supposedly opaque app launcher
Can confirm, so I looked into this. The blur has to be always on so that opaque surfaces can transition to being translucent without jarring transitions. The blur is basically a no-op when the surface is opaque, so there isn't a performance penalty. Thank you! |
SUMMARY The panel and applet/widget popups like the application launcher and tray menu still have their background blurred even when panel is set to opaque or adaptive (and a window is maximized). This can be observed during animations that involve fading in/out (opening widget popups) or manually decreasing panel/popup opacity (eg. with Meta+Scroll set to Change opacity in window action settings). I don't know what optimizations are set in place by KWin for blur but this sounds like unnecessary GPU usage if the blur is still being calculated but not being useful because the surfaces are fully opaque. STEPS TO REPRODUCE 1. Show Panel Configuration > Opacity > Adaptive/Opaque 2. Make sure panel is in opaque mode (Maximize a window if set to Adaptive) 3. Hover over widgets or open them to trigger some fade-in animations Or alternatively, Meta+Scroll down on a panel or widget popup OBSERVED RESULT You can notice blur is still being applied behind the panel and its popups implying blur is always active even when visually unnecessary or irrelevant. EXPECTED RESULT When the panel and its popups are opaque, disable background unnecessary blur. SOFTWARE/OS VERSIONS KDE Plasma Version: 6.4.3 KDE Frameworks Version: 6.16.0 Qt Version: 6.9.1 ADDITIONAL INFORMATION May worsen performance or battery life on systems with integrated GPUs or on battery power, especially if users chose to make the panel opaque just for this reason while still keeping the global blur effect enabled for other more meaningful windows.