github wiki replacement / mkdocs-docs (#2147)

* Add wiki based on mkdocs

* wording fixes

* fix github bg color on narrow

* Fix left sidebar section headers being bigger than pages

* fix hover accent

* fix list rendering on fractional layout

* fix videos

* fix automatic full links

* remove redundant commented css

* improve dark mode contrast

* update pygments for better child node coloring

* update logo

* remove blank lines

* add systemd language hint

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Co-authored-by: Ivan Molodetskikh <yalterz@gmail.com>

1 files changed, 375 insertions, 0 deletions

diff --git a/docs/wiki/Configuration:-Key-Bindings.md b/docs/wiki/Configuration:-Key-Bindings.md
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+### Overview
+
+Key bindings are declared in the `binds {}` section of the config.
+
+> [!NOTE]
+> This is one of the few sections that *does not* get automatically filled with defaults if you omit it, so make sure to copy it from the default config.
+
+Each bind is a hotkey followed by one action enclosed in curly brackets.
+For example:
+
+```kdl
+binds {
+    Mod+Left { focus-column-left; }
+    Super+Alt+L { spawn "swaylock"; }
+}
+```
+
+The hotkey consists of modifiers separated by `+` signs, followed by an XKB key name in the end.
+
+Valid modifiers are:
+
+- `Ctrl` or `Control`;
+- `Shift`;
+- `Alt`;
+- `Super` or `Win`;
+- `ISO_Level3_Shift` or `Mod5`—this is the AltGr key on certain layouts;
+- `ISO_Level5_Shift`: can be used with an xkb lv5 option like `lv5:caps_switch`;
+- `Mod`.
+
+`Mod` is a special modifier that is equal to `Super` when running niri on a TTY, and to `Alt` when running niri as a nested winit window.
+This way, you can test niri in a window without causing too many conflicts with the host compositor's key bindings.
+For this reason, most of the default keys use the `Mod` modifier.
+
+<sup>Since: 25.05</sup> You can customize the `Mod` key [in the `input` section of the config](./Configuration:-Input.md#mod-key-mod-key-nested).
+
+> [!TIP]
+> To find an XKB name for a particular key, you may use a program like [`wev`](https://git.sr.ht/~sircmpwn/wev).
+>
+> Open it from a terminal and press the key that you want to detect.
+> In the terminal, you will see output like this:
+>
+> ```
+> [14:     wl_keyboard] key: serial: 757775; time: 44940343; key: 113; state: 1 (pressed)
+>                       sym: Left         (65361), utf8: ''
+> [14:     wl_keyboard] key: serial: 757776; time: 44940432; key: 113; state: 0 (released)
+>                       sym: Left         (65361), utf8: ''
+> [14:     wl_keyboard] key: serial: 757777; time: 44940753; key: 114; state: 1 (pressed)
+>                       sym: Right        (65363), utf8: ''
+> [14:     wl_keyboard] key: serial: 757778; time: 44940846; key: 114; state: 0 (released)
+>                       sym: Right        (65363), utf8: ''
+> ```
+>
+> Here, look at `sym: Left` and `sym: Right`: these are the key names.
+> I was pressing the left and the right arrow in this example.
+>
+> Keep in mind that binding shifted keys requires spelling out Shift and the unshifted version of the key, according to your XKB layout.
+> For example, on the US QWERTY layout, <kbd>&lt;</kbd> is on <kbd>Shift</kbd> + <kbd>,</kbd>, so to bind it, you spell out something like `Mod+Shift+Comma`.
+>
+> As another example, if you've configured the French [BÉPO](https://en.wikipedia.org/wiki/B%C3%89PO) XKB layout, your <kbd>&lt;</kbd> is on <kbd>AltGr</kbd> + <kbd>«</kbd>.
+> <kbd>AltGr</kbd> is `ISO_Level3_Shift`, or equivalently `Mod5`, so to bind it, you spell out something like `Mod+Mod5+guillemotleft`.
+>
+> When resolving latin keys, niri will search for the *first* configured XKB layout that has the latin key.
+> So for example with US QWERTY and RU layouts configured, US QWERTY will be used for latin binds.
+
+<sup>Since: 0.1.8</sup> Binds will repeat by default (i.e. holding down a bind will make it trigger repeatedly).
+You can disable that for specific binds with `repeat=false`:
+
+```kdl
+binds {
+    Mod+T repeat=false { spawn "alacritty"; }
+}
+```
+
+Binds can also have a cooldown, which will rate-limit the bind and prevent it from repeatedly triggering too quickly.
+
+```kdl
+binds {
+    Mod+T cooldown-ms=500 { spawn "alacritty"; }
+}
+```
+
+This is mostly useful for the scroll bindings.
+
+### Scroll Bindings
+
+You can bind mouse wheel scroll ticks using the following syntax.
+These binds will change direction based on the `natural-scroll` setting.
+
+```kdl
+binds {
+    Mod+WheelScrollDown cooldown-ms=150 { focus-workspace-down; }
+    Mod+WheelScrollUp   cooldown-ms=150 { focus-workspace-up; }
+    Mod+WheelScrollRight                { focus-column-right; }
+    Mod+WheelScrollLeft                 { focus-column-left; }
+}
+```
+
+Similarly, you can bind touchpad scroll "ticks".
+Touchpad scrolling is continuous, so for these binds it is split into discrete intervals based on distance travelled.
+
+These binds are also affected by touchpad's `natural-scroll`, so these example binds are "inverted", since niri has `natural-scroll` enabled for touchpads by default.
+
+```kdl
+binds {
+    Mod+TouchpadScrollDown { spawn "wpctl" "set-volume" "@DEFAULT_AUDIO_SINK@" "0.02+"; }
+    Mod+TouchpadScrollUp   { spawn "wpctl" "set-volume" "@DEFAULT_AUDIO_SINK@" "0.02-"; }
+}
+```
+
+Both mouse wheel and touchpad scroll binds will prevent applications from receiving any scroll events when their modifiers are held down.
+For example, if you have a `Mod+WheelScrollDown` bind, then while holding `Mod`, all mouse wheel scrolling will be consumed by niri.
+
+### Mouse Click Bindings
+
+<sup>Since: 25.01</sup>
+
+You can bind mouse clicks using the following syntax.
+
+```kdl
+binds {
+    Mod+MouseLeft    { close-window; }
+    Mod+MouseRight   { close-window; }
+    Mod+MouseMiddle  { close-window; }
+    Mod+MouseForward { close-window; }
+    Mod+MouseBack    { close-window; }
+}
+```
+
+Mouse clicks operate on the window that was focused at the time of the click, not the window you're clicking.
+
+Note that binding `Mod+MouseLeft` or `Mod+MouseRight` will override the corresponding gesture (moving or resizing the window).
+
+### Custom Hotkey Overlay Titles
+
+<sup>Since: 25.02</sup>
+
+The hotkey overlay (the Important Hotkeys dialog) shows a hardcoded list of binds.
+You can customize this list using the `hotkey-overlay-title` property.
+
+To add a bind to the hotkey overlay, set the property to the title that you want to show:
+```kdl
+binds {
+    Mod+Shift+S hotkey-overlay-title="Toggle Dark/Light Style" { spawn "some-script.sh"; }
+}
+```
+
+Binds with custom titles are listed after the hardcoded binds and before non-customized Spawn binds.
+
+To remove a hardcoded bind from the hotkey overlay, set the property to null:
+```kdl
+binds {
+    Mod+Q hotkey-overlay-title=null { close-window; }
+}
+```
+
+> [!TIP]
+> When multiple key combinations are bound to the same action:
+> - If any of the binds has a custom hotkey overlay title, niri will show that bind.
+> - Otherwise, if any of the binds has a null title, niri will hide the bind.
+> - Otherwise, niri will show the first key combination.
+
+Custom titles support [Pango markup](https://docs.gtk.org/Pango/pango_markup.html):
+
+```kdl
+binds {
+    Mod+Shift+S hotkey-overlay-title="<b>Toggle</b> <span foreground='red'>Dark</span>/Light Style" { spawn "some-script.sh"; }
+}
+```
+
+![Custom markup example.](https://github.com/user-attachments/assets/2a2ba914-bfa7-4dfa-bb5e-49839034765d)
+
+### Actions
+
+Every action that you can bind is also available for programmatic invocation via `niri msg action`.
+Run `niri msg action` to get a full list of actions along with their short descriptions.
+
+Here are a few actions that benefit from more explanation.
+
+#### `spawn`
+
+Run a program.
+
+`spawn` accepts a path to the program binary as the first argument, followed by arguments to the program.
+For example:
+
+```kdl
+binds {
+    // Run alacritty.
+    Mod+T { spawn "alacritty"; }
+
+    // Run `wpctl set-volume @DEFAULT_AUDIO_SINK@ 0.1+`.
+    XF86AudioRaiseVolume { spawn "wpctl" "set-volume" "@DEFAULT_AUDIO_SINK@" "0.1+"; }
+}
+```
+
+> [!TIP]
+>
+> <sup>Since: 0.1.5</sup>
+>
+> Spawn bindings have a special `allow-when-locked=true` property that makes them work even while the session is locked:
+>
+> ```kdl
+> binds {
+>     // This mute bind will work even when the session is locked.
+>     XF86AudioMute allow-when-locked=true { spawn "wpctl" "set-mute" "@DEFAULT_AUDIO_SINK@" "toggle"; }
+> }
+> ```
+
+Currently, niri *does not* use a shell to run commands, which means that you need to manually separate arguments.
+
+```kdl
+binds {
+    // Correct: every argument is in its own quotes.
+    Mod+T { spawn "alacritty" "-e" "/usr/bin/fish"; }
+
+    // Wrong: will interpret the whole `alacritty -e /usr/bin/fish` string as the binary path.
+    Mod+D { spawn "alacritty -e /usr/bin/fish"; }
+
+    // Wrong: will pass `-e /usr/bin/fish` as one argument, which alacritty won't understand.
+    Mod+Q { spawn "alacritty" "-e /usr/bin/fish"; }
+}
+```
+
+This also means that you cannot expand environment variables or `~`.
+If you need this, you can run the command through a shell manually.
+
+```kdl
+binds {
+    // Wrong: no shell expansion here. These strings will be passed literally to the program.
+    Mod+T { spawn "grim" "-o" "$MAIN_OUTPUT" "~/screenshot.png"; }
+
+    // Correct: run this through a shell manually so that it can expand the arguments.
+    // Note that the entire command is passed as a SINGLE argument,
+    // because shell will do its own argument splitting by whitespace.
+    Mod+D { spawn "sh" "-c" "grim -o $MAIN_OUTPUT ~/screenshot.png"; }
+
+    // You can also use a shell to run multiple commands,
+    // use pipes, process substitution, and so on.
+    Mod+Q { spawn "sh" "-c" "notify-send clipboard \"$(wl-paste)\""; }
+}
+```
+
+As a special case, niri will expand `~` to the home directory *only* at the beginning of the program name.
+
+```kdl
+binds {
+    // This will work: one ~ at the very beginning.
+    Mod+T { spawn "~/scripts/do-something.sh"; }
+}
+```
+
+#### `quit`
+
+Exit niri after showing a confirmation dialog to avoid accidentally triggering it.
+
+```kdl
+binds {
+    Mod+Shift+E { quit; }
+}
+```
+
+If you want to skip the confirmation dialog, set the flag like so:
+
+```kdl
+binds {
+    Mod+Shift+E { quit skip-confirmation=true; }
+}
+```
+
+#### `do-screen-transition`
+
+<sup>Since: 0.1.6</sup>
+
+Freeze the screen for a brief moment then crossfade to the new contents.
+
+```kdl
+binds {
+    Mod+Return { do-screen-transition; }
+}
+```
+
+This action is mainly useful to trigger from scripts changing the system theme or style (between light and dark for example).
+It makes transitions like this, where windows change their style one by one, look smooth and synchronized.
+
+For example, using the GNOME color scheme setting:
+
+```shell
+niri msg action do-screen-transition
+dconf write /org/gnome/desktop/interface/color-scheme "\"prefer-dark\""
+```
+
+By default, the screen is frozen for 250 ms to give windows time to redraw, before the crossfade.
+You can set this delay like this:
+
+```kdl
+binds {
+    Mod+Return { do-screen-transition delay-ms=100; }
+}
+```
+
+Or, in scripts:
+
+```shell
+niri msg action do-screen-transition --delay-ms 100
+```
+
+#### `toggle-window-rule-opacity`
+
+<sup>Since: 25.02</sup>
+
+Toggle the opacity window rule of the focused window.
+This only has an effect if the window's opacity window rule is already set to semitransparent.
+
+```kdl
+binds {
+    Mod+O { toggle-window-rule-opacity; }
+}
+```
+
+#### `screenshot`, `screenshot-screen`, `screenshot-window`
+
+Actions for taking screenshots.
+
+- `screenshot`: opens the built-in interactive screenshot UI.
+- `screenshot-screen`, `screenshow-window`: takes a screenshot of the focused screen or window respectively.
+
+The screenshot is both stored to the clipboard and saved to disk, according to the [`screenshot-path` option](./Configuration:-Miscellaneous.md#screenshot-path).
+
+<sup>Since: 25.02</sup> You can disable saving to disk for a specific bind with the `write-to-disk=false` property:
+
+```kdl
+binds {
+    Ctrl+Print { screenshot-screen write-to-disk=false; }
+    Alt+Print { screenshot-window write-to-disk=false; }
+}
+```
+
+In the interactive screenshot UI, pressing <kbd>Ctrl</kbd><kbd>C</kbd> will copy the screenshot to the clipboard without writing it to disk.
+
+<sup>Since: 25.05</sup> You can hide the mouse pointer in screenshots with the `show-pointer=false` property:
+
+```kdl
+binds {
+    // The pointer will be hidden by default
+    // (you can still show it by pressing P).
+    Print { screenshot show-pointer=false; }
+
+    // The pointer will be hidden on the screenshot.
+    Ctrl+Print { screenshot-screen show-pointer=false; }
+}
+```
+
+#### `toggle-keyboard-shortcuts-inhibit`
+
+<sup>Since: 25.02</sup>
+
+Applications such as remote-desktop clients and software KVM switches may request that niri stops processing its keyboard shortcuts so that they may, for example, forward the key presses as-is to a remote machine.
+`toggle-keyboard-shortcuts-inhibit` is an escape hatch that toggles the inhibitor.
+It's a good idea to bind it, so a buggy application can't hold your session hostage.
+
+```kdl
+binds {
+    Mod+Escape { toggle-keyboard-shortcuts-inhibit; }
+}
+```
+
+You can also make certain binds ignore inhibiting with the `allow-inhibiting=false` property.
+They will always be handled by niri and never passed to the window.
+
+```kdl
+binds {
+    // This bind will always work, even when using a virtual machine.
+    Super+Alt+L allow-inhibiting=false { spawn "swaylock"; }
+}
+```