client: Unify margins handling

Currently all the shell integrations except of xdg-shell pass
full surface size to resizeFromApplyConfigure.

xdg-shell behavior is not even consistent between the first and the
consequent calls to resizeFromApplyConfigure.

This replaces QWaylandWindow::customMargins with
QWaylandWindow::windowContentMargins in order to being able to retrieve
set_window_geometry margins separately from the geometry itself
and makes xdg-shell passing the geometry consistently as full surface
size removing the need in special casing.

This also makes QWaylandWindow::clientSizeMargins public so e.g.
xdg-shell can compute out absolute position for window content geometry
without special casing decorations

Pick-to: 6.5
Change-Id: I1b98afc8b5c867ecb7cc586267b13f7ec4b1a88c
Reviewed-by: David Edmundson <davidedmundson@kde.org>

3 files changed, 24 insertions, 38 deletions

diff --git a/src/client/qwaylandwindow.cpp b/src/client/qwaylandwindow.cpp
index 6aa2c6ab..a77cce5a 100644
--- a/src/client/qwaylandwindow.cpp
+++ b/src/client/qwaylandwindow.cpp
@@ -460,20 +460,6 @@ void QWaylandWindow::repositionFromApplyConfigure(const QPoint &globalPosition)
 void QWaylandWindow::resizeFromApplyConfigure(const QSize &sizeWithMargins, const QPoint &offset)
 {
     QMargins margins = clientSideMargins();
-
-    // Exclude shadows from margins once they are excluded from window geometry
-    // 1) First resizeFromApplyConfigure() call will have sizeWithMargins equal to surfaceSize()
-    //    which has full margins (shadows included).
-    // 2) Following resizeFromApplyConfigure() calls should have sizeWithMargins equal to
-    //    windowContentGeometry() which excludes shadows, therefore in this case we have to
-    //    exclude them too in order not to accidentally apply smaller size to the window.
-    if (sizeWithMargins != surfaceSize()) {
-        if (mWindowDecorationEnabled)
-            margins = mWindowDecoration->margins(QWaylandAbstractDecoration::ShadowsExcluded);
-        if (!mCustomMargins.isNull())
-            margins -= mCustomMargins;
-    }
-
     int widthWithoutMargins = qMax(sizeWithMargins.width() - (margins.left() + margins.right()), 1);
     int heightWithoutMargins = qMax(sizeWithMargins.height() - (margins.top() + margins.bottom()), 1);
     QRect geometry(windowGeometry().topLeft(), QSize(widthWithoutMargins, heightWithoutMargins));
@@ -808,11 +794,6 @@ QMargins QWaylandWindow::clientSideMargins() const
     return mWindowDecorationEnabled ? mWindowDecoration->margins() : QMargins{};
 }
 
-QMargins QWaylandWindow::customMargins() const
-{
-    return mCustomMargins;
-}
-
 void QWaylandWindow::setCustomMargins(const QMargins &margins) {
     const QMargins oldMargins = mCustomMargins;
     mCustomMargins = margins;
@@ -827,11 +808,7 @@ QSize QWaylandWindow::surfaceSize() const
     return geometry().marginsAdded(clientSideMargins()).size();
 }
 
-/*!
- * Window geometry as defined by the xdg-shell spec (in wl_surface coordinates)
- * topLeft is where the shadow stops and the decorations border start.
- */
-QRect QWaylandWindow::windowContentGeometry() const
+QMargins QWaylandWindow::windowContentMargins() const
 {
     QMargins shadowMargins;
 
@@ -841,7 +818,17 @@ QRect QWaylandWindow::windowContentGeometry() const
     if (!mCustomMargins.isNull())
         shadowMargins += mCustomMargins;
 
-    return QRect(QPoint(shadowMargins.left(), shadowMargins.top()), surfaceSize().shrunkBy(shadowMargins));
+    return shadowMargins;
+}
+
+/*!
+ * Window geometry as defined by the xdg-shell spec (in wl_surface coordinates)
+ * topLeft is where the shadow stops and the decorations border start.
+ */
+QRect QWaylandWindow::windowContentGeometry() const
+{
+    const QMargins margins = windowContentMargins();
+    return QRect(QPoint(margins.left(), margins.top()), surfaceSize().shrunkBy(margins));
 }
 
 /*!
diff --git a/src/client/qwaylandwindow_p.h b/src/client/qwaylandwindow_p.h
index 185de69a..22b42a9a 100644
--- a/src/client/qwaylandwindow_p.h
+++ b/src/client/qwaylandwindow_p.h
@@ -118,9 +118,10 @@ public:
     bool waitForFrameSync(int timeout);
 
     QMargins frameMargins() const override;
-    QMargins customMargins() const;
+    QMargins clientSideMargins() const;
     void setCustomMargins(const QMargins &margins) override;
     QSize surfaceSize() const;
+    QMargins windowContentMargins() const;
     QRect windowContentGeometry() const;
     QPointF mapFromWlSurface(const QPointF &surfacePosition) const;
 
@@ -239,7 +240,6 @@ protected:
     virtual void doHandleFrameCallback();
     virtual QRect defaultGeometry() const;
     void sendExposeEvent(const QRect &rect);
-    QMargins clientSideMargins() const;
 
     QWaylandDisplay *mDisplay = nullptr;
 
diff --git a/src/plugins/shellintegration/xdg-shell/qwaylandxdgshell.cpp b/src/plugins/shellintegration/xdg-shell/qwaylandxdgshell.cpp
index 6a4acf86..6303fbc9 100644
--- a/src/plugins/shellintegration/xdg-shell/qwaylandxdgshell.cpp
+++ b/src/plugins/shellintegration/xdg-shell/qwaylandxdgshell.cpp
@@ -45,7 +45,7 @@ QWaylandXdgSurface::Toplevel::~Toplevel()
 void QWaylandXdgSurface::Toplevel::applyConfigure()
 {
     if (!(m_applied.states & (Qt::WindowMaximized|Qt::WindowFullScreen)))
-        m_normalSize = m_xdgSurface->m_window->windowFrameGeometry().size();
+        m_normalSize = m_xdgSurface->m_window->windowContentGeometry().size();
 
     if ((m_pending.states & Qt::WindowActive) && !(m_applied.states & Qt::WindowActive)
         && !m_xdgSurface->m_window->display()->isKeyboardAvailable())
@@ -88,7 +88,7 @@ void QWaylandXdgSurface::Toplevel::applyConfigure()
     }
 
     if (!surfaceSize.isEmpty())
-        m_xdgSurface->m_window->resizeFromApplyConfigure(surfaceSize);
+        m_xdgSurface->m_window->resizeFromApplyConfigure(surfaceSize.grownBy(m_xdgSurface->m_window->windowContentMargins()));
 
     m_applied = m_pending;
     qCDebug(lcQpaWayland) << "Applied pending xdg_toplevel configure event:" << m_applied.size << m_applied.states;
@@ -446,18 +446,17 @@ void QWaylandXdgSurface::setPopup(QWaylandWindow *parent)
 
     auto positioner = new QtWayland::xdg_positioner(m_shell->create_positioner());
     // set_popup expects a position relative to the parent
-    QPoint topLeftMargins = QPoint(m_window->customMargins().left(), m_window->customMargins().top());
-    QPoint parentMargins = QPoint(parent->customMargins().left(), parent->customMargins().top());
-    QPoint transientPos = m_window->geometry().topLeft() + topLeftMargins; // this is absolute
-    transientPos -= parent->geometry().topLeft() + parentMargins;
-    if (parent->decoration()) {
-        transientPos.setX(transientPos.x() + parent->decoration()->margins(QWaylandAbstractDecoration::ShadowsExcluded).left());
-        transientPos.setY(transientPos.y() + parent->decoration()->margins(QWaylandAbstractDecoration::ShadowsExcluded).top());
-    }
+    QRect windowGeometry = m_window->windowContentGeometry();
+    QMargins windowMargins = m_window->windowContentMargins() - m_window->clientSideMargins();
+    QMargins parentMargins = parent->windowContentMargins() - parent->clientSideMargins();
+    QPoint transientPos = m_window->geometry().topLeft(); // this is absolute
+    transientPos += QPoint(windowMargins.left(), windowMargins.top());
+    transientPos -= parent->geometry().topLeft();
+    transientPos -= QPoint(parentMargins.left(), parentMargins.top());
     positioner->set_anchor_rect(transientPos.x(), transientPos.y(), 1, 1);
     positioner->set_anchor(QtWayland::xdg_positioner::anchor_top_left);
     positioner->set_gravity(QtWayland::xdg_positioner::gravity_bottom_right);
-    positioner->set_size(m_window->windowContentGeometry().width(), m_window->windowContentGeometry().height());
+    positioner->set_size(windowGeometry.width(), windowGeometry.height());
     positioner->set_constraint_adjustment(QtWayland::xdg_positioner::constraint_adjustment_slide_x
         | QtWayland::xdg_positioner::constraint_adjustment_slide_y);
     m_popup = new Popup(this, parent, positioner);