Introduce a Toplevel::clientContentPos() -> QPoint

This describes an additional offset for the client content. On X11
our client content position matches with the window - the window
decoration is part of the overall content coordinate system.

On Wayland the content is an own texture starting at 0/0. Thus a
mapping to texture coordinates will be required when server side
decorations are provided. The new information is used in the scene's
to adjust the rendering and generating of quads.

deleted.cpp

@@ -78,6 +78,7 @@ void Deleted::copyToDeleted(Toplevel* c)
     desk = c->desktop();
     activityList = c->activities();
     contentsRect = QRect(c->clientPos(), c->clientSize());
+    m_contentPos = c->clientContentPos();
     transparent_rect = c->transparentRect();
     m_layer = c->layer();
     m_frame = c->frameId();

deleted.h

@@ -49,6 +49,9 @@ public:
     virtual QStringList activities() const;
     virtual QPoint clientPos() const;
     virtual QSize clientSize() const;
+    QPoint clientContentPos() const override {
+        return m_contentPos;
+    }
     virtual QRect transparentRect() const;
     virtual bool isDeleted() const;
     virtual xcb_window_t frameId() const override;
@@ -93,6 +96,7 @@ private:
     int desk;
     QStringList activityList;
     QRect contentsRect; // for clientPos()/clientSize()
+    QPoint m_contentPos;
     QRect transparent_rect;
     xcb_window_t m_frame;
 

scene.cpp

@@ -827,7 +827,7 @@ WindowQuadList Scene::Window::buildQuads(bool force) const
         QRegion center = toplevel->transparentRect();
         QRegion decoration = (client && true ?
                               QRegion(client->decorationRect()) : shape()) - center;
-        ret = makeQuads(WindowQuadContents, contents);
+        ret = makeQuads(WindowQuadContents, contents, client->clientContentPos());
 
         QRect rects[4];
         bool isShadedClient = false;
@@ -910,16 +910,16 @@ WindowQuadList Scene::Window::makeDecorationQuads(const QRect *rects, const QReg
     return list;
 }
 
-WindowQuadList Scene::Window::makeQuads(WindowQuadType type, const QRegion& reg) const
+WindowQuadList Scene::Window::makeQuads(WindowQuadType type, const QRegion& reg, const QPoint &textureOffset) const
 {
     WindowQuadList ret;
     foreach (const QRect & r, reg.rects()) {
         WindowQuad quad(type);
         // TODO asi mam spatne pravy dolni roh - bud tady, nebo v jinych castech
-        quad[ 0 ] = WindowVertex(r.x(), r.y(), r.x(), r.y());
-        quad[ 1 ] = WindowVertex(r.x() + r.width(), r.y(), r.x() + r.width(), r.y());
-        quad[ 2 ] = WindowVertex(r.x() + r.width(), r.y() + r.height(), r.x() + r.width(), r.y() + r.height());
-        quad[ 3 ] = WindowVertex(r.x(), r.y() + r.height(), r.x(), r.y() + r.height());
+        quad[ 0 ] = WindowVertex(r.x(), r.y(), r.x() + textureOffset.x(), r.y() + textureOffset.y());
+        quad[ 1 ] = WindowVertex(r.x() + r.width(), r.y(), r.x() + r.width() + textureOffset.x(), r.y() + textureOffset.y());
+        quad[ 2 ] = WindowVertex(r.x() + r.width(), r.y() + r.height(), r.x() + r.width() + textureOffset.x(), r.y() + r.height() + textureOffset.y());
+        quad[ 3 ] = WindowVertex(r.x(), r.y() + r.height(), r.x() + textureOffset.x(), r.y() + r.height() + textureOffset.y());
         ret.append(quad);
     }
     return ret;

scene.h

@@ -275,7 +275,7 @@ public:
     void referencePreviousPixmap();
     void unreferencePreviousPixmap();
 protected:
-    WindowQuadList makeQuads(WindowQuadType type, const QRegion& reg) const;
+    WindowQuadList makeQuads(WindowQuadType type, const QRegion& reg, const QPoint &textureOffset = QPoint(0, 0)) const;
     WindowQuadList makeDecorationQuads(const QRect *rects, const QRegion &region) const;
     /**
      * @brief Returns the WindowPixmap for this Window.

scene_qpainter.cpp

@@ -280,7 +280,7 @@ void SceneQPainter::Window::performPaint(int mask, QRegion region, WindowPaintDa
     renderWindowDecorations(painter);
 
     // render content
-    const QRect src = QRect(toplevel->clientPos(), toplevel->clientSize());
+    const QRect src = QRect(toplevel->clientPos() + toplevel->clientContentPos(), toplevel->clientSize());
     painter->drawImage(toplevel->clientPos(), pixmap->image(), src);
 
     if (!opaque) {

shell_client.cpp

@@ -200,6 +200,11 @@ QPoint ShellClient::clientPos() const
     return QPoint(0, 0);
 }
 
+QPoint ShellClient::clientContentPos() const
+{
+    return -1 * clientPos();
+}
+
 QSize ShellClient::clientSize() const
 {
     // TODO: connect for changes

shell_client.h

@@ -44,6 +44,7 @@ public:
 
     QStringList activities() const override;
     QPoint clientPos() const override;
+    QPoint clientContentPos() const override;
     QSize clientSize() const override;
     QRect transparentRect() const override;
     bool shouldUnredirect() const override;

toplevel.h

@@ -226,6 +226,11 @@ public:
     bool isOnActiveScreen() const;
     int screen() const; // the screen where the center is
     virtual QPoint clientPos() const = 0; // inside of geometry()
+    /**
+     * Describes how the client's content maps to the window geometry including the frame.
+     * The default implementation is a 1:1 mapping meaning the frame is part of the content.
+     **/
+    virtual QPoint clientContentPos() const;
     virtual QSize clientSize() const = 0;
     virtual QRect visibleRect() const; // the area the window occupies on the screen
     virtual QRect decorationRect() const; // rect including the decoration shadows
@@ -774,6 +779,11 @@ inline const QSharedPointer<QOpenGLFramebufferObject> &Toplevel::internalFramebu
     return m_internalFBO;
 }
 
+inline QPoint Toplevel::clientContentPos() const
+{
+    return QPoint(0, 0);
+}
+
 template <class T, class U>
 inline T *Toplevel::findInList(const QList<T*> &list, std::function<bool (const U*)> func)
 {