kwineffects: Expose internalId

autotests/test_window_paint_data.cpp

@@ -336,6 +336,9 @@ public:
     {
         return 0;
     }
+    QUuid internalId() const override {
+        return QUuid();
+    }
 
 private:
     qreal m_opacity = 1.0;

src/effects.cpp

@@ -2055,6 +2055,7 @@ TOPLEVEL_HELPER(bool, isOutline, isOutline)
 TOPLEVEL_HELPER(bool, isLockScreen, isLockScreen)
 TOPLEVEL_HELPER(pid_t, pid, pid)
 TOPLEVEL_HELPER(qlonglong, windowId, window)
+TOPLEVEL_HELPER(QUuid, internalId, internalId)
 
 #undef TOPLEVEL_HELPER
 

src/effects.h

@@ -500,6 +500,7 @@ public:
 
     pid_t pid() const override;
     qlonglong windowId() const override;
+    QUuid internalId() const override;
 
     QRect decorationInnerRect() const override;
     KDecoration2::Decoration *decoration() const override;

src/libkwineffects/kwineffects.h

@@ -2656,6 +2656,15 @@ public:
      * @since 5.21
      */
     virtual qlonglong windowId() const = 0;
+    /**
+     * Returns the internal id of the window that uniquely identifies it. The main difference
+     * between internalId() and windowId() is that the latter one works as expected only on X11,
+     * while the former is unique regardless of the window system.
+     *
+     * Note that the internaId() has special meaning only to kwin.
+     * @since 5.24
+     */
+    virtual QUuid internalId() const = 0;
 
     /**
      * Can be used to by effects to store arbitrary data in the EffectWindow.