Separate QObserverInterface, QObservableInterface and QObserver

This just refactors the above classes into their own files and adusts
the #includes throughout the project.

Change-Id: Ie53b8d19f2c9f7119940d27137c4bb90cd7df805
Reviewed-by: Paul Lemire <paul.lemire@kdab.com>

54 files changed, 662 insertions, 180 deletions

diff --git a/src/core/core-components/qabstracteffect.cpp b/src/core/core-components/qabstracteffect.cpp
index 664d3b24c..8c4a0991a 100644
--- a/src/core/core-components/qabstracteffect.cpp
+++ b/src/core/core-components/qabstracteffect.cpp
@@ -41,6 +41,7 @@
 
 #include "qabstracteffect.h"
 #include "qabstracttechnique.h"
+#include <Qt3DCore/qscenepropertychange.h>
 
 /*!
  * \class QAbstractEffect
diff --git a/src/core/core-components/qabstracteffect.h b/src/core/core-components/qabstracteffect.h
index 01bd114ea..57e370a01 100644
--- a/src/core/core-components/qabstracteffect.h
+++ b/src/core/core-components/qabstracteffect.h
@@ -43,7 +43,6 @@
 #define QT3D_QABSTRACTEFFECT_H
 
 #include <Qt3DCore/node.h>
-#include <Qt3DCore/qchangearbiter.h>
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/core/core-components/qabstractrenderpass.cpp b/src/core/core-components/qabstractrenderpass.cpp
index 73c8eb181..e2cb937ac 100644
--- a/src/core/core-components/qabstractrenderpass.cpp
+++ b/src/core/core-components/qabstractrenderpass.cpp
@@ -41,6 +41,7 @@
 
 #include "qabstractrenderpass.h"
 #include "qabstractshader.h"
+#include <Qt3DCore/qscenepropertychange.h>
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/core/core-components/qabstractrenderpass.h b/src/core/core-components/qabstractrenderpass.h
index 17ebc596c..4bfe4f0f2 100644
--- a/src/core/core-components/qabstractrenderpass.h
+++ b/src/core/core-components/qabstractrenderpass.h
@@ -43,7 +43,6 @@
 #define QT3D_QABSTRACTRENDERPASS_H
 
 #include <Qt3DCore/node.h>
-#include <Qt3DCore/qchangearbiter.h>
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/core/core-components/qabstracttechnique.cpp b/src/core/core-components/qabstracttechnique.cpp
index 73f6601a7..226e7ea28 100644
--- a/src/core/core-components/qabstracttechnique.cpp
+++ b/src/core/core-components/qabstracttechnique.cpp
@@ -42,6 +42,8 @@
 #include "qabstracttechnique.h"
 #include "qabstractrenderpass.h"
 
+#include <Qt3DCore/qscenepropertychange.h>
+
 /*!
  * \class QAbstractTechnique
  * \namespace Qt3D
diff --git a/src/core/core-components/qabstracttechnique.h b/src/core/core-components/qabstracttechnique.h
index 1035429e8..13be3b5ec 100644
--- a/src/core/core-components/qabstracttechnique.h
+++ b/src/core/core-components/qabstracttechnique.h
@@ -43,7 +43,6 @@
 #define QT3D_QABSTRACTTECHNIQUE_H
 
 #include <Qt3DCore/node.h>
-#include <Qt3DCore/qchangearbiter.h>
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/core/core.pri b/src/core/core.pri
index 50d2e2ebb..030ae99e4 100644
--- a/src/core/core.pri
+++ b/src/core/core.pri
@@ -22,7 +22,12 @@ HEADERS += \
     $$PWD/qscheduler.h \
     $$PWD/cameracontroller.h \
     $$PWD/qchangearbiter.h \
-    $$PWD/corelogging.h
+    $$PWD/corelogging.h \
+    $$PWD/qscenechange.h \
+    $$PWD/qscenepropertychange.h \
+    $$PWD/qobservableinterface.h \
+    $$PWD/qobservable.h \
+    $$PWD/qobserverinterface.h
 
 SOURCES += \
     $$PWD/window.cpp \
@@ -30,4 +35,7 @@ SOURCES += \
     $$PWD/qscheduler.cpp \
     $$PWD/cameracontroller.cpp \
     $$PWD/qchangearbiter.cpp \
-    $$PWD/corelogging.cpp
+    $$PWD/corelogging.cpp \
+    $$PWD/qobservableinterface.cpp \
+    $$PWD/qobservable.cpp \
+    $$PWD/qobserverinterface.cpp
diff --git a/src/core/nodes/entity.cpp b/src/core/nodes/entity.cpp
index 126fa8da7..b302bbe1a 100644
--- a/src/core/nodes/entity.cpp
+++ b/src/core/nodes/entity.cpp
@@ -44,6 +44,7 @@
 #include "abstracttransform.h"
 #include "matrixtransform.h"
 
+#include <Qt3DCore/qscenepropertychange.h>
 #include <QMetaObject>
 #include <QMetaProperty>
 #include "corelogging.h"
diff --git a/src/core/nodes/entity.h b/src/core/nodes/entity.h
index ded0370a9..7a9ef8a10 100644
--- a/src/core/nodes/entity.h
+++ b/src/core/nodes/entity.h
@@ -44,7 +44,6 @@
 
 #include <Qt3DCore/node.h>
 #include <Qt3DCore/qt3dcore_global.h>
-#include <Qt3DCore/qchangearbiter.h>
 
 #include <QMatrix4x4>
 #include <QUuid>
diff --git a/src/core/nodes/node.cpp b/src/core/nodes/node.cpp
index 235f8d4f1..210a6a0de 100644
--- a/src/core/nodes/node.cpp
+++ b/src/core/nodes/node.cpp
@@ -43,6 +43,8 @@
 
 #include "entity.h"
 
+#include <Qt3DCore/qscenepropertychange.h>
+
 #include <QEvent>
 #include <QMetaObject>
 #include <QMetaProperty>
diff --git a/src/core/nodes/node.h b/src/core/nodes/node.h
index b1daaa23f..a013aa6c2 100644
--- a/src/core/nodes/node.h
+++ b/src/core/nodes/node.h
@@ -44,7 +44,7 @@
 
 #include <QObject>
 #include <Qt3DCore/qt3dcore_global.h>
-#include <Qt3DCore/qchangearbiter.h>
+#include <Qt3DCore/qobservable.h>
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/core/qchangearbiter.cpp b/src/core/qchangearbiter.cpp
index 3dc89c18a..984d4ae21 100644
--- a/src/core/qchangearbiter.cpp
+++ b/src/core/qchangearbiter.cpp
@@ -53,34 +53,6 @@ QT_BEGIN_NAMESPACE
 
 namespace Qt3D {
 
-QObservable::QObservable()
-    : m_observers()
-    , m_lock(QReadWriteLock::NonRecursive)
-{
-}
-
-void QObservable::registerObserver(QObserverInterface *observer)
-{
-    QWriteLocker locker(&m_lock);
-    if (!m_observers.contains(observer))
-        m_observers.append(observer);
-}
-
-void QObservable::unregisterObserver(QObserverInterface *observer)
-{
-    QWriteLocker locker(&m_lock);
-    m_observers.removeOne(observer);
-}
-
-// This calls sceneChangeEvent on the QChangeArbiter
-void QObservable::notifyObservers(const QSceneChangePtr &e)
-{
-    QReadLocker locker(&m_lock);
-    Q_FOREACH (QObserverInterface *observer, m_observers)
-        observer->sceneChangeEvent(e);
-}
-
-
 QChangeArbiter::QChangeArbiter(QObject *parent)
     : QObject(parent)
     , m_mutex(QMutex::Recursive)
diff --git a/src/core/qchangearbiter.h b/src/core/qchangearbiter.h
index 90ff31301..7d05a13b2 100644
--- a/src/core/qchangearbiter.h
+++ b/src/core/qchangearbiter.h
@@ -44,12 +44,13 @@
 
 #include <Qt3DCore/qt3dcore_global.h>
 #include <QObject>
-#include <QDateTime>
+#include <Qt3DCore/qobserverinterface.h>
+#include <Qt3DCore/qscenechange.h>
+
 #include <QDebug>
 #include <QFlags>
 #include <QMutex>
 #include <QReadWriteLock>
-#include <QSharedPointer>
 #include <QThreadStorage>
 #include <QVariant>
 #include <QVector>
@@ -60,135 +61,7 @@ QT_BEGIN_NAMESPACE
 namespace Qt3D {
 
 class Component;
-
-enum ChangeFlag {
-    NodeCreated             = 0x00000001,
-    NodeAboutToBeDeleted    = 0x00000002,
-    NodeDeleted             = 0x00000004,
-    NodeStatus              = 0x00000008,
-    ComponentAdded          = 0x00000010,
-    ComponentRemoved        = 0x00000020,
-    ComponentUpdated        = 0x00000040,
-    AllChanges              = 0x00000FFF
-};
-Q_DECLARE_FLAGS(ChangeFlags, ChangeFlag)
-Q_DECLARE_OPERATORS_FOR_FLAGS(ChangeFlags)
-
-
-class QObserverInterface;
 class QObservableInterface;
-
-class QT3DCORESHARED_EXPORT QSceneChange
-{
-public:
-    enum Priority {
-        High,
-        Standard,
-        Low
-    };
-
-    QSceneChange(ChangeFlag type, QObservableInterface *observable, Priority priority = Standard)
-        : m_type(type),
-          m_priority(priority),
-          m_timestamp(QDateTime::currentMSecsSinceEpoch())
-    {
-        m_subject.m_observable = observable;
-        m_subjectType = ObservableType;
-    }
-
-    QSceneChange(ChangeFlag type, Component *component, Priority priority = Standard)
-        : m_type(type),
-          m_priority(priority),
-          m_timestamp(QDateTime::currentMSecsSinceEpoch())
-    {
-        m_subject.m_component = component;
-        m_subjectType = ComponentType;
-    }
-
-    union {
-        QObservableInterface *m_observable;
-        Component *m_component;
-    } m_subject;
-
-    enum ObservableType {
-        ObservableType,
-        ComponentType
-    } m_subjectType;
-
-    ChangeFlag m_type;
-    Priority m_priority;
-    qint64 m_timestamp;
-
-    // TODO: add timestamp from central clock and priority level
-    // These can be used to resolve any conflicts between events
-    // posted from different aspects
-};
-
-typedef QSharedPointer<QSceneChange> QSceneChangePtr;
-
-class QT3DCORESHARED_EXPORT QScenePropertyChange : public QSceneChange
-{
-public:
-    QScenePropertyChange(ChangeFlag type, QObservableInterface *subject, Priority priority = Standard)
-        : QSceneChange(type, subject, priority)
-    {
-    }
-
-    QScenePropertyChange(ChangeFlag type, Component *component, Priority priority = Standard)
-        : QSceneChange(type, component, priority)
-    {
-    }
-
-    QByteArray m_propertyName;
-    QVariant m_value;
-};
-
-typedef QSharedPointer<QScenePropertyChange> QScenePropertyChangePtr;
-
-
-class QT3DCORESHARED_EXPORT QObservableInterface
-{
-public:
-    virtual ~QObservableInterface() {}
-
-    virtual void registerObserver(QObserverInterface *observer) = 0;
-    virtual void unregisterObserver(QObserverInterface *observer) = 0;
-
-protected:
-    virtual void notifyObservers(const QSceneChangePtr &e) = 0;
-};
-
-
-class QT3DCORESHARED_EXPORT QObservable : public QObservableInterface
-{
-public:
-    QObservable();
-
-    // In most cases, only the QChangeArbiter should be able to call these
-    // Might be worth making them private and having a friend class
-    void registerObserver(QObserverInterface *observer) Q_DECL_OVERRIDE;
-    void unregisterObserver(QObserverInterface *observer) Q_DECL_OVERRIDE;
-
-protected:
-    void notifyObservers(const QSceneChangePtr &e) Q_DECL_OVERRIDE;
-
-    const QList<QObserverInterface *> &observers() const { return m_observers; }
-
-private:
-    QList<QObserverInterface *> m_observers;
-    QReadWriteLock m_lock;
-};
-
-
-class QObserverInterface
-{
-public:
-    virtual ~QObserverInterface() {}
-
-    virtual void sceneChangeEvent(const QSceneChangePtr &e) = 0;
-};
-
-
 class QJobManagerInterface;
 
 class QT3DCORESHARED_EXPORT QChangeArbiter : public QObject,
diff --git a/src/core/qobservable.cpp b/src/core/qobservable.cpp
new file mode 100644
index 000000000..f4bf85011
--- /dev/null
+++ b/src/core/qobservable.cpp
@@ -0,0 +1,78 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Klaralvdalens Datakonsult AB (KDAB).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Qt3D 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.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qobservable.h"
+#include <Qt3DCore/qobserverinterface.h>
+
+QT_BEGIN_NAMESPACE
+
+namespace Qt3D {
+
+QObservable::QObservable()
+    : m_observers()
+    , m_lock(QReadWriteLock::NonRecursive)
+{
+}
+
+void QObservable::registerObserver(QObserverInterface *observer)
+{
+    QWriteLocker locker(&m_lock);
+    if (!m_observers.contains(observer))
+        m_observers.append(observer);
+}
+
+void QObservable::unregisterObserver(QObserverInterface *observer)
+{
+    QWriteLocker locker(&m_lock);
+    m_observers.removeOne(observer);
+}
+
+// This calls sceneChangeEvent on the QChangeArbiter
+void QObservable::notifyObservers(const QSceneChangePtr &e)
+{
+    QReadLocker locker(&m_lock);
+    Q_FOREACH (QObserverInterface *observer, m_observers)
+        observer->sceneChangeEvent(e);
+}
+
+} // namespace Qt3D
+
+QT_END_NAMESPACE
diff --git a/src/core/qobservable.h b/src/core/qobservable.h
new file mode 100644
index 000000000..ba552a8f3
--- /dev/null
+++ b/src/core/qobservable.h
@@ -0,0 +1,76 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Klaralvdalens Datakonsult AB (KDAB).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Qt3D 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 QT3D_QOBSERVABLE_H
+#define QT3D_QOBSERVABLE_H
+
+#include <Qt3DCore/qobservableinterface.h>
+#include <QReadWriteLock>
+
+QT_BEGIN_NAMESPACE
+
+namespace Qt3D {
+
+class QT3DCORESHARED_EXPORT QObservable : public QObservableInterface
+{
+public:
+    QObservable();
+
+    // In most cases, only the QChangeArbiter should be able to call these
+    // Might be worth making them private and having a friend class
+    void registerObserver(QObserverInterface *observer) Q_DECL_OVERRIDE;
+    void unregisterObserver(QObserverInterface *observer) Q_DECL_OVERRIDE;
+
+protected:
+    void notifyObservers(const QSceneChangePtr &e) Q_DECL_OVERRIDE;
+
+    const QList<QObserverInterface *> &observers() const { return m_observers; }
+
+private:
+    QList<QObserverInterface *> m_observers;
+    QReadWriteLock m_lock;
+};
+
+} // namespace Qt3D
+
+QT_END_NAMESPACE
+
+#endif // QT3D_QOBSERVABLE_H
diff --git a/src/core/qobservableinterface.cpp b/src/core/qobservableinterface.cpp
new file mode 100644
index 000000000..20106ddb3
--- /dev/null
+++ b/src/core/qobservableinterface.cpp
@@ -0,0 +1,54 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Klaralvdalens Datakonsult AB (KDAB).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Qt3D 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.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qobservableinterface.h"
+
+QT_BEGIN_NAMESPACE
+
+namespace Qt3D {
+
+QObservableInterface::~QObservableInterface()
+{
+}
+
+} // namespace Qt3D
+
+QT_END_NAMESPACE
diff --git a/src/core/qobservableinterface.h b/src/core/qobservableinterface.h
new file mode 100644
index 000000000..1ae6aa5a3
--- /dev/null
+++ b/src/core/qobservableinterface.h
@@ -0,0 +1,70 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Klaralvdalens Datakonsult AB (KDAB).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Qt3D 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 QT3D_QOBSERVABLEINTERFACE_H
+#define QT3D_QOBSERVABLEINTERFACE_H
+
+#include <Qt3DCore/qt3dcore_global.h>
+#include <Qt3DCore/qscenechange.h>
+
+QT_BEGIN_NAMESPACE
+
+namespace Qt3D {
+
+class QObserverInterface;
+
+class QT3DCORESHARED_EXPORT QObservableInterface
+{
+public:
+    virtual ~QObservableInterface();
+
+    virtual void registerObserver(QObserverInterface *observer) = 0;
+    virtual void unregisterObserver(QObserverInterface *observer) = 0;
+
+protected:
+    virtual void notifyObservers(const QSceneChangePtr &e) = 0;
+};
+
+} // namespace Qt3D
+
+QT_END_NAMESPACE
+
+#endif // QT3D_QOBSERVABLEINTERFACE_H
diff --git a/src/core/qobserverinterface.cpp b/src/core/qobserverinterface.cpp
new file mode 100644
index 000000000..6c7d0f893
--- /dev/null
+++ b/src/core/qobserverinterface.cpp
@@ -0,0 +1,54 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Klaralvdalens Datakonsult AB (KDAB).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Qt3D 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.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qobserverinterface.h"
+
+QT_BEGIN_NAMESPACE
+
+namespace Qt3D {
+
+QObserverInterface::~QObserverInterface()
+{
+}
+
+} // namespace Qt3D
+
+QT_END_NAMESPACE
diff --git a/src/core/qobserverinterface.h b/src/core/qobserverinterface.h
new file mode 100644
index 000000000..ab3142b94
--- /dev/null
+++ b/src/core/qobserverinterface.h
@@ -0,0 +1,63 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Klaralvdalens Datakonsult AB (KDAB).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Qt3D 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 QT3D_QOBSERVERINTERFACE_H
+#define QT3D_QOBSERVERINTERFACE_H
+
+#include <Qt3DCore/qt3dcore_global.h>
+#include <Qt3DCore/qscenechange.h>
+
+QT_BEGIN_NAMESPACE
+
+namespace Qt3D {
+
+class QT3DCORESHARED_EXPORT QObserverInterface
+{
+public:
+    virtual ~QObserverInterface();
+    virtual void sceneChangeEvent(const QSceneChangePtr &e) = 0;
+};
+
+} // namespace Qt3D
+
+QT_END_NAMESPACE
+
+#endif // QT3D_QOBSERVERINTERFACE_H
diff --git a/src/core/qscenechange.h b/src/core/qscenechange.h
new file mode 100644
index 000000000..7e452f38f
--- /dev/null
+++ b/src/core/qscenechange.h
@@ -0,0 +1,121 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Klaralvdalens Datakonsult AB (KDAB).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Qt3D 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 QT3D_QSCENECHANGE_H
+#define QT3D_QSCENECHANGE_H
+
+#include <Qt3DCore/qt3dcore_global.h>
+#include <QDateTime>
+#include <QSharedPointer>
+
+QT_BEGIN_NAMESPACE
+
+namespace Qt3D {
+
+enum ChangeFlag {
+    NodeCreated             = 0x00000001,
+    NodeAboutToBeDeleted    = 0x00000002,
+    NodeDeleted             = 0x00000004,
+    NodeStatus              = 0x00000008,
+    ComponentAdded          = 0x00000010,
+    ComponentRemoved        = 0x00000020,
+    ComponentUpdated        = 0x00000040,
+    AllChanges              = 0x00000FFF
+};
+Q_DECLARE_FLAGS(ChangeFlags, ChangeFlag)
+Q_DECLARE_OPERATORS_FOR_FLAGS(ChangeFlags)
+
+class Component;
+class QObservableInterface;
+
+class QT3DCORESHARED_EXPORT QSceneChange
+{
+public:
+    enum Priority {
+        High,
+        Standard,
+        Low
+    };
+
+    QSceneChange(ChangeFlag type, QObservableInterface *observable, Priority priority = Standard)
+        : m_type(type),
+          m_priority(priority),
+          m_timestamp(QDateTime::currentMSecsSinceEpoch())
+    {
+        m_subject.m_observable = observable;
+        m_subjectType = ObservableType;
+    }
+
+    QSceneChange(ChangeFlag type, Component *component, Priority priority = Standard)
+        : m_type(type),
+          m_priority(priority),
+          m_timestamp(QDateTime::currentMSecsSinceEpoch())
+    {
+        m_subject.m_component = component;
+        m_subjectType = ComponentType;
+    }
+
+    union {
+        QObservableInterface *m_observable;
+        Component *m_component;
+    } m_subject;
+
+    enum ObservableType {
+        ObservableType,
+        ComponentType
+    } m_subjectType;
+
+    ChangeFlag m_type;
+    Priority m_priority;
+    qint64 m_timestamp;
+
+    // TODO: add timestamp from central clock and priority level
+    // These can be used to resolve any conflicts between events
+    // posted from different aspects
+};
+
+typedef QSharedPointer<QSceneChange> QSceneChangePtr;
+
+} // namespace Qt3D
+
+QT_END_NAMESPACE
+
+#endif // QT3D_QSCENECHANGE_H
diff --git a/src/core/qscenepropertychange.h b/src/core/qscenepropertychange.h
new file mode 100644
index 000000000..839f0d329
--- /dev/null
+++ b/src/core/qscenepropertychange.h
@@ -0,0 +1,76 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Klaralvdalens Datakonsult AB (KDAB).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Qt3D 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 QT3D_QSCENEPROPERTYCHANGE_H
+#define QT3D_QSCENEPROPERTYCHANGE_H
+
+#include <Qt3DCore/qscenechange.h>
+
+#include <QVariant>
+
+QT_BEGIN_NAMESPACE
+
+namespace Qt3D {
+
+class QT3DCORESHARED_EXPORT QScenePropertyChange : public QSceneChange
+{
+public:
+    QScenePropertyChange(ChangeFlag type, QObservableInterface *subject, Priority priority = Standard)
+        : QSceneChange(type, subject, priority)
+    {
+    }
+
+    QScenePropertyChange(ChangeFlag type, Component *component, Priority priority = Standard)
+        : QSceneChange(type, component, priority)
+    {
+    }
+
+    QByteArray m_propertyName;
+    QVariant m_value;
+};
+
+typedef QSharedPointer<QScenePropertyChange> QScenePropertyChangePtr;
+
+} // namespace Qt3D
+
+QT_END_NAMESPACE
+
+#endif // QT3D_QSCENEPROPERTYCHANGE_H
diff --git a/src/core/transforms/transform.cpp b/src/core/transforms/transform.cpp
index e0350db0e..c5abefc77 100644
--- a/src/core/transforms/transform.cpp
+++ b/src/core/transforms/transform.cpp
@@ -41,6 +41,7 @@
 
 #include "transform.h"
 
+#include <Qt3DCore/qscenepropertychange.h>
 #include <matrixtransform.h>
 
 QT_BEGIN_NAMESPACE
diff --git a/src/render/backend/framegraph/cameraselectornode.cpp b/src/render/backend/framegraph/cameraselectornode.cpp
index a3e2cdcf3..17c70df28 100644
--- a/src/render/backend/framegraph/cameraselectornode.cpp
+++ b/src/render/backend/framegraph/cameraselectornode.cpp
@@ -45,6 +45,7 @@
 #include <Qt3DRenderer/renderer.h>
 #include <Qt3DRenderer/rendereraspect.h>
 #include <Qt3DCore/qaspectmanager.h>
+#include <Qt3DCore/qchangearbiter.h>
 #include <Qt3DCore/entity.h>
 #include "renderlogging.h"
 
diff --git a/src/render/backend/framegraph/cameraselectornode.h b/src/render/backend/framegraph/cameraselectornode.h
index 911634df6..f7cfe194b 100644
--- a/src/render/backend/framegraph/cameraselectornode.h
+++ b/src/render/backend/framegraph/cameraselectornode.h
@@ -43,6 +43,7 @@
 #define QT3D_RENDER_CAMERASELECTOR_H
 
 #include <Qt3DRenderer/framegraphnode.h>
+#include <Qt3DCore/qobserverinterface.h>
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/render/backend/framegraph/framegraphnode.h b/src/render/backend/framegraph/framegraphnode.h
index adf5de19c..6916c47a2 100644
--- a/src/render/backend/framegraph/framegraphnode.h
+++ b/src/render/backend/framegraph/framegraphnode.h
@@ -44,7 +44,6 @@
 
 #include <qglobal.h>
 #include <QVector>
-#include <Qt3DCore/qchangearbiter.h>
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/render/backend/framegraph/renderpassfilternode.cpp b/src/render/backend/framegraph/renderpassfilternode.cpp
index 0f6d45a06..ab420a22e 100644
--- a/src/render/backend/framegraph/renderpassfilternode.cpp
+++ b/src/render/backend/framegraph/renderpassfilternode.cpp
@@ -45,6 +45,7 @@
 #include "renderpasscriterion.h"
 #include "renderpassfilter.h"
 #include <Qt3DCore/qaspectmanager.h>
+#include <Qt3DCore/qchangearbiter.h>
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/render/backend/framegraph/renderpassfilternode.h b/src/render/backend/framegraph/renderpassfilternode.h
index 264a3784b..37cfbb502 100644
--- a/src/render/backend/framegraph/renderpassfilternode.h
+++ b/src/render/backend/framegraph/renderpassfilternode.h
@@ -42,7 +42,7 @@
 #ifndef QT3D_RENDER_RENDERPASSFILTER_H
 #define QT3D_RENDER_RENDERPASSFILTER_H
 
-#include <Qt3DCore/qchangearbiter.h>
+#include <Qt3DCore/qobserverinterface.h>
 #include <Qt3DRenderer/framegraphnode.h>
 #include <QList>
 
diff --git a/src/render/backend/framegraph/techniquefilternode.cpp b/src/render/backend/framegraph/techniquefilternode.cpp
index a72ac47ef..00eed7df6 100644
--- a/src/render/backend/framegraph/techniquefilternode.cpp
+++ b/src/render/backend/framegraph/techniquefilternode.cpp
@@ -46,6 +46,7 @@
 #include "rendereraspect.h"
 #include <Qt3DCore/qaspectmanager.h>
 #include <Qt3DCore/qchangearbiter.h>
+#include <Qt3DCore/qscenepropertychange.h>
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/render/backend/framegraph/techniquefilternode.h b/src/render/backend/framegraph/techniquefilternode.h
index a8d1508f8..cce1c0431 100644
--- a/src/render/backend/framegraph/techniquefilternode.h
+++ b/src/render/backend/framegraph/techniquefilternode.h
@@ -43,6 +43,8 @@
 #define QT3D_RENDER_TECHNIQUEFILTER_H
 
 #include <Qt3DRenderer/framegraphnode.h>
+#include <Qt3DCore/qobserverinterface.h>
+
 #include <QList>
 #include <QString>
 #include <QVariant>
diff --git a/src/render/backend/framegraph/viewportnode.cpp b/src/render/backend/framegraph/viewportnode.cpp
index 7fe9a47a5..6e20deeb8 100644
--- a/src/render/backend/framegraph/viewportnode.cpp
+++ b/src/render/backend/framegraph/viewportnode.cpp
@@ -40,10 +40,14 @@
 ****************************************************************************/
 
 #include "viewportnode.h"
+
 #include <Qt3DRenderer/renderer.h>
 #include <Qt3DRenderer/rendereraspect.h>
-#include <Qt3DCore/qaspectmanager.h>
 #include <Qt3DRenderer/viewport.h>
+
+#include <Qt3DCore/qaspectmanager.h>
+#include <Qt3DCore/qchangearbiter.h>
+
 #include <QDebug>
 
 QT_BEGIN_NAMESPACE
diff --git a/src/render/backend/framegraph/viewportnode.h b/src/render/backend/framegraph/viewportnode.h
index 2f034c489..f8a4b3cf6 100644
--- a/src/render/backend/framegraph/viewportnode.h
+++ b/src/render/backend/framegraph/viewportnode.h
@@ -43,6 +43,7 @@
 #define QT3D_RENDER_VIEWPORTNODE_H
 
 #include <Qt3DRenderer/framegraphnode.h>
+#include <Qt3DCore/qobserverinterface.h>
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/render/backend/rendercamera.cpp b/src/render/backend/rendercamera.cpp
index f619f31e3..041655cc5 100644
--- a/src/render/backend/rendercamera.cpp
+++ b/src/render/backend/rendercamera.cpp
@@ -47,6 +47,7 @@
 
 #include <entity.h>
 #include <qaspectmanager.h>
+#include <Qt3DCore/qscenepropertychange.h>
 
 #include <QOpenGLContext>
 
diff --git a/src/render/backend/rendercamera.h b/src/render/backend/rendercamera.h
index 4b33fbaac..f5dea4eb6 100644
--- a/src/render/backend/rendercamera.h
+++ b/src/render/backend/rendercamera.h
@@ -42,7 +42,7 @@
 #ifndef QT3D_RENDER_RENDERCAMERA_H
 #define QT3D_RENDER_RENDERCAMERA_H
 
-#include <Qt3DCore/qchangearbiter.h>
+#include <Qt3DCore/qobserverinterface.h>
 
 #include <QMatrix4x4>
 #include <QRectF>
diff --git a/src/render/backend/rendereffect.cpp b/src/render/backend/rendereffect.cpp
index 6411d9556..bc1ef46df 100644
--- a/src/render/backend/rendereffect.cpp
+++ b/src/render/backend/rendereffect.cpp
@@ -45,6 +45,8 @@
 #include <Qt3DCore/qaspectmanager.h>
 #include <Qt3DCore/qabstracteffect.h>
 #include <Qt3DCore/qabstracttechnique.h>
+#include <Qt3DCore/qchangearbiter.h>
+#include <Qt3DCore/qscenepropertychange.h>
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/render/backend/rendereffect.h b/src/render/backend/rendereffect.h
index 050e8e0a8..95792d3ec 100644
--- a/src/render/backend/rendereffect.h
+++ b/src/render/backend/rendereffect.h
@@ -44,7 +44,7 @@
 
 #include <QList>
 #include <Qt3DRenderer/qt3drenderer_global.h>
-#include <Qt3DCore/qchangearbiter.h>
+#include <Qt3DCore/qobserverinterface.h>
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/render/backend/rendermaterial.cpp b/src/render/backend/rendermaterial.cpp
index b78913cf8..c62d7d495 100644
--- a/src/render/backend/rendermaterial.cpp
+++ b/src/render/backend/rendermaterial.cpp
@@ -50,6 +50,7 @@
 #include <material.h>
 
 #include <qaspectmanager.h>
+#include <Qt3DCore/qscenepropertychange.h>
 
 #include <QOpenGLShaderProgram>
 
diff --git a/src/render/backend/rendermaterial.h b/src/render/backend/rendermaterial.h
index e6ae13325..e178f7ae9 100644
--- a/src/render/backend/rendermaterial.h
+++ b/src/render/backend/rendermaterial.h
@@ -44,7 +44,7 @@
 
 #include <QVariant>
 
-#include <Qt3DCore/qchangearbiter.h>
+#include <Qt3DCore/qobserverinterface.h>
 
 #include <Qt3DRenderer/quniformvalue.h>
 #include <Qt3DRenderer/rendertextureprovider.h>
diff --git a/src/render/backend/rendermesh.cpp b/src/render/backend/rendermesh.cpp
index 2a2c57f9d..22ad07536 100644
--- a/src/render/backend/rendermesh.cpp
+++ b/src/render/backend/rendermesh.cpp
@@ -49,6 +49,8 @@
 #include <meshdata.h>
 #include <technique.h>
 
+#include <Qt3DCore/qscenepropertychange.h>
+
 #include <QOpenGLContext>
 #include <QOpenGLShaderProgram>
 #include <QReadWriteLock>
diff --git a/src/render/backend/rendermesh.h b/src/render/backend/rendermesh.h
index 4018ccc28..730d69235 100644
--- a/src/render/backend/rendermesh.h
+++ b/src/render/backend/rendermesh.h
@@ -43,7 +43,7 @@
 #define QT3D_RENDER_RENDERMESH_H
 
 #include <Qt3DCore/axisalignedboundingbox.h>
-#include <Qt3DCore/qchangearbiter.h>
+#include <Qt3DCore/qobserverinterface.h>
 #include <Qt3DCore/qhandle.h>
 
 QT_BEGIN_NAMESPACE
diff --git a/src/render/backend/rendernode.cpp b/src/render/backend/rendernode.cpp
index e63b94435..7da511d7e 100644
--- a/src/render/backend/rendernode.cpp
+++ b/src/render/backend/rendernode.cpp
@@ -56,6 +56,7 @@
 #include <qaspectmanager.h>
 #include <sphere.h>
 #include <entity.h>
+#include <Qt3DCore/qscenepropertychange.h>
 
 #include <QMatrix4x4>
 #include <QString>
diff --git a/src/render/backend/rendernode.h b/src/render/backend/rendernode.h
index aaa6614d9..447b92ac4 100644
--- a/src/render/backend/rendernode.h
+++ b/src/render/backend/rendernode.h
@@ -42,7 +42,7 @@
 #ifndef QT3D_RENDER_RENDERNODE_H
 #define QT3D_RENDER_RENDERNODE_H
 
-#include <Qt3DCore/qchangearbiter.h>
+#include <Qt3DCore/qobserverinterface.h>
 #include <Qt3DCore/qhandle.h>
 #include <QVector>
 
diff --git a/src/render/backend/renderrenderpass.cpp b/src/render/backend/renderrenderpass.cpp
index f56fadf90..045220187 100644
--- a/src/render/backend/renderrenderpass.cpp
+++ b/src/render/backend/renderrenderpass.cpp
@@ -43,6 +43,8 @@
 #include "renderer.h"
 #include "rendereraspect.h"
 #include <Qt3DCore/qaspectmanager.h>
+#include <Qt3DCore/qchangearbiter.h>
+#include <Qt3DCore/qscenepropertychange.h>
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/render/backend/renderrenderpass.h b/src/render/backend/renderrenderpass.h
index 9ab7a55c9..b1b95197e 100644
--- a/src/render/backend/renderrenderpass.h
+++ b/src/render/backend/renderrenderpass.h
@@ -42,8 +42,8 @@
 #ifndef QT3D_RENDER_RENDERRENDERPASS_H
 #define QT3D_RENDER_RENDERRENDERPASS_H
 
-#include <Qt3DCore/qchangearbiter.h>
 #include <Qt3DRenderer/qt3drenderer_global.h>
+#include <Qt3DCore/qobserverinterface.h>
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/render/backend/rendertechnique.cpp b/src/render/backend/rendertechnique.cpp
index 5d14a750c..74bdda9e7 100644
--- a/src/render/backend/rendertechnique.cpp
+++ b/src/render/backend/rendertechnique.cpp
@@ -48,6 +48,7 @@
 #include "renderer.h"
 #include <Qt3DCore/qaspectmanager.h>
 #include <Qt3DCore/qchangearbiter.h>
+#include <Qt3DCore/qscenepropertychange.h>
 
 #include <QDebug>
 
diff --git a/src/render/backend/rendertechnique.h b/src/render/backend/rendertechnique.h
index 674c09824..984d94ac9 100644
--- a/src/render/backend/rendertechnique.h
+++ b/src/render/backend/rendertechnique.h
@@ -44,7 +44,7 @@
 
 #include <QVector>
 #include <QStringList>
-#include <Qt3DCore/qchangearbiter.h>
+#include <Qt3DCore/qobserverinterface.h>
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/render/frontend/cameraselector.h b/src/render/frontend/cameraselector.h
index b978cb3c4..f63297dcf 100644
--- a/src/render/frontend/cameraselector.h
+++ b/src/render/frontend/cameraselector.h
@@ -45,6 +45,9 @@
 #include <Qt3DRenderer/qt3drenderer_global.h>
 #include <Qt3DRenderer/framegraphitem.h>
 
+#include <Qt3DCore/node.h>
+#include <Qt3DCore/qscenepropertychange.h>
+
 QT_BEGIN_NAMESPACE
 
 namespace Qt3D {
diff --git a/src/render/frontend/effect.h b/src/render/frontend/effect.h
index fee10f1c3..edb661c68 100644
--- a/src/render/frontend/effect.h
+++ b/src/render/frontend/effect.h
@@ -44,7 +44,6 @@
 
 #include <Qt3DCore/qabstracteffect.h>
 #include <Qt3DCore/node.h>
-#include <Qt3DCore/qchangearbiter.h>
 #include <Qt3DRenderer/qt3drenderer_global.h>
 
 QT_BEGIN_NAMESPACE
diff --git a/src/render/frontend/framegraphitem.h b/src/render/frontend/framegraphitem.h
index 3f0dd54cb..d4c57e78b 100644
--- a/src/render/frontend/framegraphitem.h
+++ b/src/render/frontend/framegraphitem.h
@@ -43,8 +43,7 @@
 #define QT3D_FRAMEGRAPHNODE_H
 
 #include <Qt3DRenderer/qt3drenderer_global.h>
-#include <Qt3DCore/node.h>
-#include <Qt3DCore/qchangearbiter.h>
+#include <QObject>
 
 QT_BEGIN_NAMESPACE
 
@@ -61,6 +60,7 @@ public:
     void setEnabled(bool enabled);
     bool isEnabled() const;
 
+    // TODO: Remove this
 Q_SIGNALS:
     virtual void enabledChanged() = 0;
 
diff --git a/src/render/frontend/material.cpp b/src/render/frontend/material.cpp
index 921d96ad0..c322160b7 100644
--- a/src/render/frontend/material.cpp
+++ b/src/render/frontend/material.cpp
@@ -41,11 +41,11 @@
 
 #include "material.h"
 //#include <Qt3DCore/qabstractmaterial_p.h>
-#include <qchangearbiter.h>
 #include <texture.h>
 #include "qabstracteffect.h"
 #include "renderlogging.h"
 #include "parameter.h"
+#include <Qt3DCore/qscenepropertychange.h>
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/render/frontend/mesh.cpp b/src/render/frontend/mesh.cpp
index 74c46e07f..217afed81 100644
--- a/src/render/frontend/mesh.cpp
+++ b/src/render/frontend/mesh.cpp
@@ -41,13 +41,14 @@
 
 #include "mesh.h"
 
-#include <qchangearbiter.h>
 #include <QDebug>
 #include <QFile>
 #include <QFileInfo>
 
 #include <objloader.h>
 
+#include <Qt3DCore/qscenepropertychange.h>
+
 QT_BEGIN_NAMESPACE
 
 namespace Qt3D {
diff --git a/src/render/frontend/renderpassfilter.h b/src/render/frontend/renderpassfilter.h
index 312c75b1d..f1a23fce4 100644
--- a/src/render/frontend/renderpassfilter.h
+++ b/src/render/frontend/renderpassfilter.h
@@ -45,6 +45,10 @@
 #include <Qt3DRenderer/qt3drenderer_global.h>
 #include <Qt3DRenderer/framegraphitem.h>
 #include <Qt3DRenderer/renderpasscriterion.h>
+
+#include <Qt3DCore/node.h>
+#include <Qt3DCore/qscenepropertychange.h>
+
 #include <QString>
 
 QT_BEGIN_NAMESPACE
diff --git a/src/render/frontend/rendertargetselector.h b/src/render/frontend/rendertargetselector.h
index 7adca56ae..0e67725f6 100644
--- a/src/render/frontend/rendertargetselector.h
+++ b/src/render/frontend/rendertargetselector.h
@@ -43,6 +43,7 @@
 #define QT3D_RENDERTARGETSELECTOR_H
 
 #include <Qt3DRenderer/qt3drenderer_global.h>
+#include <Qt3DCore/node.h>
 #include <Qt3DRenderer/framegraphitem.h>
 
 QT_BEGIN_NAMESPACE
diff --git a/src/render/frontend/techniquefilter.h b/src/render/frontend/techniquefilter.h
index 4d26e65aa..14369acd6 100644
--- a/src/render/frontend/techniquefilter.h
+++ b/src/render/frontend/techniquefilter.h
@@ -46,6 +46,9 @@
 #include <Qt3DRenderer/framegraphitem.h>
 #include <Qt3DRenderer/techniquecriterion.h>
 
+#include <Qt3DCore/node.h>
+#include <Qt3DCore/qscenepropertychange.h>
+
 QT_BEGIN_NAMESPACE
 
 namespace Qt3D {
diff --git a/src/render/frontend/viewport.h b/src/render/frontend/viewport.h
index aa16c2052..318b16c7a 100644
--- a/src/render/frontend/viewport.h
+++ b/src/render/frontend/viewport.h
@@ -43,6 +43,8 @@
 #define QT3D_VIEWPORT_H
 
 #include <Qt3DRenderer/framegraphitem.h>
+#include <Qt3DCore/node.h>
+#include <Qt3DCore/qscenepropertychange.h>
 #include <QtCore/QRectF>
 
 QT_BEGIN_NAMESPACE