KDE-Rounded-Corners

This effect rounds the corners of your windows and adds an outline around them without much affecting the performance of the KDE Plasma desktop (see #49 and #50).

This effect started as a fork of shapecorners with some additional contributions in Alex47's project, then I optimized and reimplemented the effect with shaders with influences from the invert effect.

I maintain this effect on KDE Plasma desktop version 5.27 to 6.4+ in various Linux distros (See tests).

Tested on

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Contributions:

• Compatibility of the effect with other effects like Wobbly windows
• Compatibility with KWin for Plasma versions 5.27 to 6.4
• Compatibility with HDR in Plasma 6.0
• Compatibility with split KWin codebase dependency starting version 6.4 - see #383
• Optimize the effect to render once instead of 5 times - see #49
• Smooth animation when a window moves to an active state
• Reimplementation with shaders, including shadows at corners and two outlines
• Ability to disable the effect when windows get maximized or tiled
• Cleanups for the plugin logic, remove unneeded dependencies from CMakeLists.txt file - by alex1701c
• Separate outline color for active and inactive windows - by OrkenWhite
• Support for language translations - by VictorR2007 (See How to add more translations?)

How to install using unofficial repositories

Copr package at matinlotfali/KDE-Rounded-Corners

sudo dnf copr enable matinlotfali/KDE-Rounded-Corners
sudo dnf install kwin-effect-roundcorners # or kwin-effect-roundcorners-x11 

AUR package by xiota

sudo pamac build kwin-effect-rounded-corners-git # or kwin-effect-rounded-corners-x11-git

NixOS package by flexagoon

nix-env -iA nixos.kde-rounded-corners

How to install using a pre-built package

Download .deb or .rpm packages from above and install them using the commands:

sudo dpkg -i ./kwin4_effect_shapecorners_debian.deb # for debian and kubuntu
sudo dnf install ./kwin4_effect_shapecorners_fedora42.rpm # for fedora
sudo zypper install ./kwin4_effect_shapecorners_tumbleweed.rpm # for opensuse tumbleweed

How to build from source code

You need to install development packages for your distribution first:

Debian based (Ubuntu, Kubuntu, KDE Neon)

• Plasma 6

  sudo apt install git cmake g++ extra-cmake-modules kwin-dev qt6-base-private-dev qt6-base-dev-tools libkf6kcmutils-dev

• Plasma 5 - by alex47:

  sudo apt install git cmake g++ extra-cmake-modules kwin-dev libkf5configwidgets-dev 

Fedora

• Plasma 6 (Fedora 40 and later)

  sudo dnf install git cmake gcc-c++ extra-cmake-modules kwin-devel kf6-kconfigwidgets-devel libepoxy-devel kf6-kcmutils-devel kf6-ki18n-devel qt6-qtbase-private-devel wayland-devel libdrm-devel

• Plasma 5 (Fedora 39)

  sudo dnf install git cmake gcc-c++ extra-cmake-modules kwin-devel kf5-kconfigwidgets-devel kf5-ki18n-devel libepoxy-devel

Arch - by https://github.com/hexa-one

sudo pacman -S git cmake extra-cmake-modules base-devel
yay -S qt5-tools

OpenSUSE - by https://github.com/mathiasgredal, https://github.com/Richardsause, and https://github.com/aaronkirschen

• Plasma 6 (by https://github.com/aaronkirschen)

  sudo zypper in git cmake gcc-c++ kf6-kconfigwidgets-devel kf6-kcmutils-devel kwin6-devel kf6-kwindowsystem-devel qt6-quick-devel qt6-core-private-devel

• Plasma 5 (by https://github.com/mathiasgredal, https://github.com/Richardsause)

  sudo zypper install git cmake gcc-c++ extra-cmake-modules libqt5-qttools-devel kconfigwidgets-devel kwindowsystem-devel kguiaddons-devel ki18n-devel knotifications-devel kwin5-devel libQt5Gui-devel libQt5OpenGL-devel libepoxy-devel libqt5-qtnetworkauth-devel

Void - by https://github.com/lay-by and https://github.com/tre-flip

xbps-install git cmake make extra-cmake-modules gettext-devel kwin-devel kf6-kconfigwidgets-devel kf6-kcmutils-devel

Then clone the source code and compile it:

git clone https://github.com/matinlotfali/KDE-Rounded-Corners
cd KDE-Rounded-Corners
mkdir build
cd build
cmake ..
cmake --build . -j
sudo make install

Note

If you are building for X11, use the command cmake .. -DKWIN_X11=ON instead of cmake ..

Note

When building for KDE Linux (https://community.kde.org/KDE_Linux) or other immutable distributions that do not provide tools like rpm-ostree, you cannot write to system paths such as /usr. To deploy a plugin in such environments, you need to build it into a user overlay and activate it using systemd-sysext.

To ensure the plugin is installed under the correct directory layout expected by KWin, use

cmake .. \
  -DCMAKE_INSTALL_PREFIX=~/kde/usr \
  -DKDE_INSTALL_PLUGINDIR=lib/qt6/plugins

instead of cmake .., and also use make install instead of sudo make install.

Once built, you can prepare the overlay by placing it under ~/kde and linking it into /var/lib/extensions/kde, where systemd-sysext expects extension roots to be located. The following command automates that:

sh ../tools/deploy-to-overlay.sh

This way, the plugin is installed in a form that systemd-sysext can recognize and load, while still preserving the integrity of the immutable root filesystem.

How to load or unload the effect

To activate the effect, you can now log out and log back in, or run the command below inside the build directory:

sh ../tools/load.sh

To fully uninstall the effect, run the following commands inside the build directory:

sh ../tools/unload.sh
sudo make uninstall

How to auto-install after KWin update

After each KWin package update, the effect becomes incompatible. So it won't load without a rebuild.

As long as the effect is not part of the KWin yet (being discussed here), you can automate the re-installation by running the command below inside the build directory:

sh ../tools/install-autorun-test.sh

The command above adds a .desktop file inside the autorun directory which checks if the effect is still compatible, If it is incompatible, the script will automatically rebuild and reinstall the effect.

Note

The script uses qdbus to show a progress bar. On Plasma 6, it is not installed by default. You need to manually install the package qtchooser.

How to adjust its settings

You can change the corner radius, outlines, exclusions, and more in:

System Settings → Workspace Behavior → Desktop Effects → Rounded Corners

Extra Tips

How to add more languages to the translation

Translations are stored in po/<lang>/kcmcorners.po. One can copy from other languages and start editing it in a different subdirectory of po.

If the kcm.ui changes, a new language template .pot can be generated by running the script tools/generate-messages.sh.

How to disable conflicting native window outline

If using Breeze (default) window decorations with Plasma 5.27 or higher you may wish to disable the native window outline, to prevent it from overlapping and causing visual glitches.

System settings → Themes → Window Decorations → Breeze → Edit icon → Shadows and Outline tab → Outline intensity (Off)

Alternatively, you can use the command below:

kwriteconfig6 --file breezerc --group Common --key OutlineIntensity "OutlineOff"
qdbus-qt6 org.kde.KWin /KWin reconfigure

How to add shadow to windows without decoration (like Steam)

You can add shadows for specific windows using the hack below. I don't know how to enforce it in my code.

1. In [ System settings ] → [ Window management ] → [ Window rules ] → [ Appearance & Fixes ]:

   Add [steam] and set [ No titlebar ] and frame to [ No ]

2. In [ System settings ] → [ Application Style ] → [ Window decoration ] → [ Breeze theme setting ] → [ Window specific overrides ]:

   Add [steam] and set [ Hide Window title bar ] to [ Yes ].

After that, the Steam window gets its shadows back.

How to add debug messages

When troubleshooting or reporting an issue, it might be useful to enable Debug logs during the build time using:

cmake .. --DCMAKE_BUILD_TYPE=Debug
cmake --build . -j

You may also need to add the default.debug=true rule in ~/.config/QtProject/qtlogging.ini. The example of the file content is:

[Rules]
*.debug=false
qt.qpa.xcb.xcberror.warning=false
default.debug=true

After the installation and loading the effect, debug messages would appear in journalctl:

journalctl -f | grep kwin

or have some colorful logs with

sh ../tools/show-kwin-logs.sh