Make QSGNode and friends extensible via a d-pointer

Convert the private void *m_reserved to a d_ptr so as to make QSGNode
inherited classes extensible without breaking binary compatibility.
QSGNode and subclasses do not create a private instance by default.

This is required by a follow-up commit where a new member needs to be
added to QSGSimpleTextureNode. Protected ctors have been added to the
superclasses of QSGSimpleTextureNode in the usual fashion.

Change-Id: I30c5f5d057654145d87f18c34c5d13a6ff5f7b11
Reviewed-by: Gunnar Sletta <gunnar.sletta@digia.com>

4 files changed, 133 insertions, 1 deletions

diff --git a/src/quick/scenegraph/coreapi/qsgnode.cpp b/src/quick/scenegraph/coreapi/qsgnode.cpp
index 6a22e0e7f9..8bf9ae8e76 100644
--- a/src/quick/scenegraph/coreapi/qsgnode.cpp
+++ b/src/quick/scenegraph/coreapi/qsgnode.cpp
@@ -40,6 +40,7 @@
 ****************************************************************************/
 
 #include "qsgnode.h"
+#include "qsgnode_p.h"
 #include "qsgrenderer_p.h"
 #include "qsgnodeupdater_p.h"
 #include "qsgmaterial.h"
@@ -267,6 +268,26 @@ QSGNode::QSGNode(NodeType type)
 }
 
 /*!
+ * Constructs a new node with the given node type.
+ *
+ * \internal
+ */
+QSGNode::QSGNode(QSGNodePrivate &dd, NodeType type)
+    : m_parent(0)
+    , m_type(type)
+    , m_firstChild(0)
+    , m_lastChild(0)
+    , m_nextSibling(0)
+    , m_previousSibling(0)
+    , m_subtreeRenderableCount(type == GeometryNodeType || type == RenderNodeType ? 1 : 0)
+    , m_nodeFlags(OwnedByParent)
+    , m_dirtyState(0)
+    , d_ptr(&dd)
+{
+    init();
+}
+
+/*!
  * \internal
  */
 void QSGNode::init()
@@ -678,6 +699,18 @@ QSGBasicGeometryNode::QSGBasicGeometryNode(NodeType type)
 
 
 /*!
+    \internal
+ */
+QSGBasicGeometryNode::QSGBasicGeometryNode(QSGBasicGeometryNodePrivate &dd, NodeType type)
+    : QSGNode(dd, type)
+    , m_geometry(0)
+    , m_matrix(0)
+    , m_clip_list(0)
+{
+}
+
+
+/*!
     Deletes this QSGBasicGeometryNode.
 
     If the node has the flag QSGNode::OwnsGeometry set, it will also delete the
@@ -808,6 +841,19 @@ QSGGeometryNode::QSGGeometryNode()
 
 
 /*!
+    \internal
+ */
+QSGGeometryNode::QSGGeometryNode(QSGGeometryNodePrivate &dd)
+    : QSGBasicGeometryNode(dd, GeometryNodeType)
+    , m_render_order(0)
+    , m_material(0)
+    , m_opaque_material(0)
+    , m_opacity(1)
+{
+}
+
+
+/*!
     Deletes this geometry node.
 
     The flags QSGNode::OwnsMaterial, QSGNode::OwnsOpaqueMaterial and
diff --git a/src/quick/scenegraph/coreapi/qsgnode.h b/src/quick/scenegraph/coreapi/qsgnode.h
index 3fa2f7fc04..d83e6bcc81 100644
--- a/src/quick/scenegraph/coreapi/qsgnode.h
+++ b/src/quick/scenegraph/coreapi/qsgnode.h
@@ -58,6 +58,9 @@ class QSGRootNode;
 class QSGGeometryNode;
 class QSGTransformNode;
 class QSGClipNode;
+class QSGNodePrivate;
+class QSGBasicGeometryNodePrivate;
+class QSGGeometryNodePrivate;
 
 class Q_QUICK_EXPORT QSGNode
 {
@@ -149,6 +152,7 @@ public:
 
 protected:
     QSGNode(NodeType type);
+    QSGNode(QSGNodePrivate &dd, NodeType type);
 
 private:
     friend class QSGRootNode;
@@ -167,7 +171,8 @@ private:
     Flags m_nodeFlags;
     DirtyState m_dirtyState;
 
-    void *m_reserved;
+protected:
+    QScopedPointer<QSGNodePrivate> d_ptr;
 };
 
 class Q_QUICK_EXPORT QSGBasicGeometryNode : public QSGNode
@@ -184,6 +189,7 @@ public:
 
 protected:
     QSGBasicGeometryNode(NodeType type);
+    QSGBasicGeometryNode(QSGBasicGeometryNodePrivate &dd, NodeType type);
 
 private:
     friend class QSGNodeUpdater;
@@ -218,6 +224,9 @@ public:
     void setInheritedOpacity(qreal opacity);
     qreal inheritedOpacity() const { return m_opacity; }
 
+protected:
+    QSGGeometryNode(QSGGeometryNodePrivate &dd);
+
 private:
     friend class QSGNodeUpdater;
 
diff --git a/src/quick/scenegraph/coreapi/qsgnode_p.h b/src/quick/scenegraph/coreapi/qsgnode_p.h
new file mode 100644
index 0000000000..b0d8088af2
--- /dev/null
+++ b/src/quick/scenegraph/coreapi/qsgnode_p.h
@@ -0,0 +1,76 @@
+/****************************************************************************
+**
+** Copyright (C) 2013 Klaralvdalens Datakonsult AB (KDAB)
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtQml module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QSGNODE_P_H
+#define QSGNODE_P_H
+
+#include <qglobal.h>
+
+QT_BEGIN_NAMESPACE
+
+class QSGNodePrivate
+{
+public:
+    QSGNodePrivate() {}
+    virtual ~QSGNodePrivate() {}
+};
+
+
+class QSGBasicGeometryNodePrivate : public QSGNodePrivate
+{
+public:
+    QSGBasicGeometryNodePrivate()
+        : QSGNodePrivate()
+    {}
+};
+
+
+class QSGGeometryNodePrivate: public QSGBasicGeometryNodePrivate
+{
+public:
+    QSGGeometryNodePrivate()
+        : QSGBasicGeometryNodePrivate()
+    {}
+};
+
+QT_END_NAMESPACE
+
+#endif // QSGNODE_P_H
diff --git a/src/quick/scenegraph/scenegraph.pri b/src/quick/scenegraph/scenegraph.pri
index 8c87e23ac9..ebf886dace 100644
--- a/src/quick/scenegraph/scenegraph.pri
+++ b/src/quick/scenegraph/scenegraph.pri
@@ -6,6 +6,7 @@ HEADERS += \
     $$PWD/coreapi/qsggeometry.h \
     $$PWD/coreapi/qsgmaterial.h \
     $$PWD/coreapi/qsgnode.h \
+    $$PWD/coreapi/qsgnode_p.h \
     $$PWD/coreapi/qsgnodeupdater_p.h \
     $$PWD/coreapi/qsgrenderer_p.h \
     $$PWD/coreapi/qsgrendernode_p.h \