Introduce Window::desiredSize property

src/interfaces/window.cpp

@@ -29,6 +29,7 @@ public:
 
     QWindow *parentWindow;
     QString scope = QStringLiteral("window");
+    QSize desiredSize = QSize(0, 0);
     Window::Anchors anchors = {Window::AnchorTop | Window::AnchorBottom | Window::AnchorLeft | Window::AnchorRight};
     int32_t exclusionZone = 0;
     Window::KeyboardInteractivity keyboardInteractivity = Window::KeyboardInteractivityNone;
@@ -141,6 +142,19 @@ void Window::setCloseOnDismissed(bool close)
     d->closeOnDismissed = close;
 }
 
+void Window::setDesiredSize(const QSize &size)
+{
+    if (d->desiredSize != size) {
+        d->desiredSize = size;
+        Q_EMIT desiredSizeChanged();
+    }
+}
+
+QSize Window::desiredSize() const
+{
+    return d->desiredSize;
+}
+
 #if QT_VERSION < QT_VERSION_CHECK(6, 6, 0)
 void Window::attachPopup(QWindow *window, xdg_popup *popup)
 {

src/interfaces/window.h

@@ -114,6 +114,13 @@ public:
     void setCloseOnDismissed(bool close);
     bool closeOnDismissed() const;
 
+    /**
+     * Sets the desired window size. This size indicates how much space the compositor is going
+     * to reserve for the window.
+     */
+    void setDesiredSize(const QSize &size);
+    QSize desiredSize() const;
+
     /**
      * Gets the LayerShell Window for a given Qt Window
      * Ownership is not transferred
@@ -132,6 +139,7 @@ Q_SIGNALS:
     void marginsChanged();
     void keyboardInteractivityChanged();
     void layerChanged();
+    void desiredSizeChanged();
 
 private:
     Window(QWindow *window);

src/qwaylandlayersurface.cpp

@@ -55,17 +55,10 @@ QWaylandLayerSurface::QWaylandLayerSurface(QtWayland::zwlr_layer_shell_v1 *shell
         setKeyboardInteractivity(m_interface->keyboardInteractivity());
     });
 
-    QSize size = window->surfaceSize();
+    setDesiredSize(m_interface->desiredSize());
-    const Window::Anchors anchors = m_interface->anchors();
+    connect(m_interface, &Window::desiredSizeChanged, this, [this]() {
-    if ((anchors & Window::AnchorLeft) && (anchors & Window::AnchorRight)) {
+        setDesiredSize(m_interface->desiredSize());
-        size.setWidth(0);
+    });
-    }
-    if ((anchors & Window::AnchorTop) && (anchors & Window::AnchorBottom)) {
-        size.setHeight(0);
-    }
-    if (size.isValid() && size != QSize(0, 0)) {
-        set_size(size.width(), size.height());
-    }
 }
 
 QWaylandLayerSurface::~QWaylandLayerSurface()
@@ -141,18 +134,8 @@ void QWaylandLayerSurface::setLayer(uint32_t layer)
         set_layer(layer);
 }
 
-void QWaylandLayerSurface::setWindowGeometry(const QRect &geometry)
+void QWaylandLayerSurface::setDesiredSize(const QSize &size)
 {
-    const bool horizontallyConstrained = m_interface->anchors() & (Window::AnchorLeft & Window::AnchorRight);
-    const bool verticallyConstrained = m_interface->anchors() & (Window::AnchorTop & Window::AnchorBottom);
-
-    QSize size = geometry.size();
-    if (horizontallyConstrained) {
-        size.setWidth(0);
-    }
-    if (verticallyConstrained) {
-        size.setHeight(0);
-    }
     set_size(size.width(), size.height());
 }
 

src/qwaylandlayersurface_p.h

@@ -39,9 +39,9 @@ public:
     void setMargins(const QMargins &margins);
     void setKeyboardInteractivity(uint32_t interactivity);
     void setLayer(uint32_t layer);
+    void setDesiredSize(const QSize &size);
 
     void applyConfigure() override;
-    void setWindowGeometry(const QRect &geometry) override;
 
 private:
     void zwlr_layer_surface_v1_configure(uint32_t serial, uint32_t width, uint32_t height) override;