SUMMARY The slide-in/out animation used for auto-hiding panels has a graphical glitch: Once the animation starts, a 1px gray line appears right next the panel. Particularly for dark color schemes (dark plasma on dark application), this bright color creates an irritating contrast, which in effect makes the sliding animation look "off"/stuttery. To illustrate the problem, I attached a screenshot of the first frame of the auto-hide animation, along with the zero-th frame as a reference. STEPS TO REPRODUCE 1. Set panel visibility to "Auto Hide" 2. Set color scheme to Breeze Dark 3. Observe the auto-hide animation of the panel The glitch is best-visible on top of an application with dark background, and may be easier to spot on a 30Hz resolution or lower. On a high-refresh-rate display, the animation will look "off" but it will be difficult to explicitly spot the 1px line. OBSERVED RESULT During the auto-hide animation, a 1px gray line appears on the innermost side of the panel. EXPECTED RESULT The panel hiding should be animation without any extra elements appearing. SOFTWARE/OS VERSIONS Linux: openSUSE Tumbleweed (also tested Ubuntu 23.04) KDE Plasma Version: 5.27.4 KDE Frameworks Version: 5.105.0 Qt Version: 5.15.9 Graphics Platform: Wayland
Created attachment 158864 [details] First frame of hide animation (slide-out to the right)
Created attachment 158865 [details] Reference panel image ("zero-th" frame of hide animation)
A possibly relevant merge request was started @ https://invent.kde.org/plasma/kwin/-/merge_requests/4206
Git commit cd94cdaf3a04227073c3f99833139a712d195d3a by Xaver Hugl. Committed on 23/06/2023 at 08:45. Pushed by zamundaaa into branch 'master'. plugins/backgroundcontrast,blur: ensure the effect is only applied behind the window When a window is translated and/or scaled, the effect must be strictly behind the window and never beyond it, as that is very noticeable. M +14 -8 src/plugins/backgroundcontrast/contrast.cpp M +13 -6 src/plugins/blur/blur.cpp https://invent.kde.org/plasma/kwin/-/commit/cd94cdaf3a04227073c3f99833139a712d195d3a
Git commit 69151896615ec272d78860b2ef42e61657f435f1 by Xaver Hugl. Committed on 23/06/2023 at 09:05. Pushed by zamundaaa into branch 'Plasma/5.27'. plugins/backgroundcontrast,blur: ensure the effect is only applied behind the window When a window is translated and/or scaled, the effect must be strictly behind the window and never beyond it, as that is very noticeable. (cherry picked from commit cd94cdaf3a04227073c3f99833139a712d195d3a) M +14 -8 src/effects/backgroundcontrast/contrast.cpp M +13 -6 src/effects/blur/blur.cpp https://invent.kde.org/plasma/kwin/-/commit/69151896615ec272d78860b2ef42e61657f435f1