Dimmer: new implementation of the screen diming in a separate component.

Modules/Background/Dimmer.qml

@@ -0,0 +1,76 @@
+import QtQuick
+import QtQuick.Effects
+import Quickshell
+import Quickshell.Wayland
+import qs.Commons
+import qs.Services
+import qs.Widgets
+
+Variants {
+  model: Quickshell.screens
+
+  delegate: Loader {
+    required property ShellScreen modelData
+
+    // Dimmer is only active on the screen where the panel is currently open.
+    active: {
+      if (Settings.isLoaded && Settings.data.general.dimDesktop && modelData !== undefined && PanelService.openedPanel !== null && PanelService.openedPanel.item !== null) {
+        return (PanelService.openedPanel.item.screen === modelData)
+      }
+
+      return false
+    }
+
+    sourceComponent: PanelWindow {
+      id: panel
+
+      property real customOpacity: 0
+
+      Component.onCompleted: {
+        if (modelData) {
+          Logger.log("Dimmer", "component loaded on", modelData.name)
+        }
+
+        // When a NPanel opens it seems it is initialized with the primary screen for a very brief moment
+        // before the screen actually updates to the proper value. We use a timer to delay the fade in to avoid
+        // a single frame flicker on the main screen when opening a panel on another screen.
+        fadeInTimer.start()
+      }
+
+      Connections {
+        target: PanelService
+        function onWillClose() {
+          customOpacity = Style.opacityNone
+        }
+      }
+
+      Timer {
+        id: fadeInTimer
+        interval: 100
+        onTriggered: customOpacity = Style.opacityHeavy
+      }
+
+      screen: modelData
+
+      WlrLayershell.layer: WlrLayer.Top
+      WlrLayershell.exclusionMode: ExclusionMode.Ignore
+      WlrLayershell.keyboardFocus: WlrKeyboardFocus.None
+      WlrLayershell.namespace: "quickshell-dimmer"
+
+      // mask: Region {}
+      anchors {
+        top: true
+        bottom: true
+        right: true
+        left: true
+      }
+
+      color: Qt.alpha(Color.mShadow, customOpacity)
+      Behavior on color {
+        ColorAnimation {
+          duration: Style.animationSlow
+        }
+      }
+    }
+  }
+}