Remove deprecated classes and functions

Mostly old messaging API

Change-Id: I17eb2206b2ede56d2f7d36375d5e711d6149019f
Reviewed-by: Paul Lemire <paul.lemire@kdab.com>

12 files changed, 24 insertions, 486 deletions

diff --git a/src/core/nodes/nodes.pri b/src/core/nodes/nodes.pri
index 785ae2b21..097f1cbc7 100644
--- a/src/core/nodes/nodes.pri
+++ b/src/core/nodes/nodes.pri
@@ -13,7 +13,6 @@ HEADERS += \
     $$PWD/qnodevisitor_p.h \
     $$PWD/propertychangehandler_p.h \
     $$PWD/qdestructionidandtypecollector_p.h \
-    $$PWD/qnodecreatedchangegenerator_p.h \
     $$PWD/qabstractnodefactory_p.h
 
 SOURCES += \
@@ -25,5 +24,4 @@ SOURCES += \
     $$PWD/qnodevisitor.cpp \
     $$PWD/qabstractnodefactory.cpp \
     $$PWD/propertychangehandler.cpp \
-    $$PWD/qdestructionidandtypecollector.cpp \
-    $$PWD/qnodecreatedchangegenerator.cpp
+    $$PWD/qdestructionidandtypecollector.cpp
diff --git a/src/core/nodes/qbackendnode.cpp b/src/core/nodes/qbackendnode.cpp
index 4138ea060..433c305cc 100644
--- a/src/core/nodes/qbackendnode.cpp
+++ b/src/core/nodes/qbackendnode.cpp
@@ -42,8 +42,6 @@
 
 #include <Qt3DCore/qaspectengine.h>
 #include <Qt3DCore/qnode.h>
-#include <Qt3DCore/qnodecommand.h>
-#include <Qt3DCore/qpropertyupdatedchange.h>
 
 #include <Qt3DCore/private/corelogging_p.h>
 
@@ -59,32 +57,10 @@ QBackendNodeMapper::~QBackendNodeMapper()
 QBackendNodePrivate::QBackendNodePrivate(QBackendNode::Mode mode)
     : q_ptr(nullptr)
     , m_mode(mode)
-    , m_arbiter(nullptr)
     , m_enabled(false)
 {
 }
 
-// Called by backend thread (renderer or other) while we are locked to sync changes
-void QBackendNodePrivate::setArbiter(QLockableObserverInterface *arbiter)
-{
-    Q_ASSERT(m_mode == QBackendNode::ReadWrite);
-    m_arbiter = arbiter;
-}
-
-// Called by backend thread/worker threads. We don't need locking
-// as setting/unsetting the arbiter cannot happen at that time
-void QBackendNodePrivate::notifyObservers(const QSceneChangePtr &e)
-{
-    Q_ASSERT(m_mode == QBackendNode::ReadWrite);
-    if (m_arbiter != nullptr)
-        m_arbiter->sceneChangeEvent(e);
-}
-
-void QBackendNodePrivate::sceneChangeEvent(const QSceneChangePtr &e)
-{
-    q_func()->sceneChangeEvent(e);
-}
-
 void QBackendNodePrivate::setEnabled(bool enabled)
 {
     m_enabled = enabled;
@@ -124,7 +100,7 @@ void QBackendNodePrivate::componentRemoved(QNode *frontend)
  */
 
 /*!
- * \fn Qt3DCore::QBackendNode *Qt3DCore::QBackendNodeMapper::create(const Qt3DCore::QNodeCreatedChangeBasePtr &change) const
+ * \fn Qt3DCore::QBackendNode *Qt3DCore::QBackendNodeMapper::create(Qt3DCore::QNodeId id) const
  *
  * \TODO
  *
@@ -219,55 +195,6 @@ QBackendNode::QBackendNode(QBackendNodePrivate &dd)
 }
 
 /*!
- * Notifies observers of scene change \a e.
- * \obsolete
- */
-void QBackendNode::notifyObservers(const QSceneChangePtr &e)
-{
-    Q_D(QBackendNode);
-    d->notifyObservers(e);
-}
-
-/*!
-    \obsolete
-
-    Send the command named \a name with contents \a data,
-    and specify \a replyTo as the command id to which the
-    reply needs to be sent.
-*/
-QNodeCommand::CommandId QBackendNode::sendCommand(const QString &name,
-                                                  const QVariant &data,
-                                                  QNodeCommand::CommandId replyTo)
-{
-    auto e = QNodeCommandPtr::create(peerId());
-    e->setName(name);
-    e->setData(data);
-    e->setReplyToCommandId(replyTo);
-    e->setDeliveryFlags(QSceneChange::Nodes);
-    notifyObservers(e);
-    return e->commandId();
-}
-
-/*!
-    Send the reply to \a command.
-    \obsolete
-*/
-void QBackendNode::sendReply(const QNodeCommandPtr &command)
-{
-    command->setDeliveryFlags(QSceneChange::Nodes);
-    notifyObservers(command);
-}
-
-/*!
- * \obsolete
- */
-void QBackendNode::initializeFromPeer(const QNodeCreatedChangeBasePtr &change)
-{
-    Q_UNUSED(change)
-    qCDebug(Nodes) << Q_FUNC_INFO << change->metaObject()->className() << "does not override";
-}
-
-/*!
  * Enables or disables the backend node by \a enabled.
  */
 void QBackendNode::setEnabled(bool enabled) Q_DECL_NOTHROW
@@ -276,25 +203,6 @@ void QBackendNode::setEnabled(bool enabled) Q_DECL_NOTHROW
     d->m_enabled = enabled;
 }
 
-/*!
- * \obsolete
- */
-void QBackendNode::sceneChangeEvent(const QSceneChangePtr &e)
-{
-    Q_D(QBackendNode);
-
-    switch (e->type()) {
-    case PropertyUpdated: {
-        auto propertyChange = qSharedPointerCast<QPropertyUpdatedChange>(e);
-        if (propertyChange->propertyName() == QByteArrayLiteral("enabled"))
-            d->m_enabled = propertyChange->value().toBool();
-        break;
-    }
-    default:
-        break;
-    }
-}
-
 } // Qt3D
 
 QT_END_NAMESPACE
diff --git a/src/core/nodes/qbackendnode.h b/src/core/nodes/qbackendnode.h
index 691375999..4af1ae996 100644
--- a/src/core/nodes/qbackendnode.h
+++ b/src/core/nodes/qbackendnode.h
@@ -40,10 +40,7 @@
 #ifndef QT3DCORE_QBACKENDNODE_H
 #define QT3DCORE_QBACKENDNODE_H
 
-#include <Qt3DCore/qnodecreatedchange.h>
 #include <Qt3DCore/qnodeid.h>
-#include <Qt3DCore/qnodecommand.h>
-#include <Qt3DCore/qscenechange.h>
 #include <Qt3DCore/qt3dcore_global.h>
 
 QT_BEGIN_NAMESPACE
@@ -62,7 +59,7 @@ class Q_3DCORESHARED_EXPORT QBackendNodeMapper
 {
 public:
     virtual ~QBackendNodeMapper();
-    virtual QBackendNode *create(const QNodeCreatedChangeBasePtr &change) const = 0;        // TODO QT6 change to only take a NodeId
+    virtual QBackendNode *create(QNodeId id) const = 0;
     virtual QBackendNode *get(QNodeId id) const = 0;
     virtual void destroy(QNodeId id) const = 0;
 };
@@ -90,20 +87,13 @@ public:
 protected:
     Q_DECLARE_PRIVATE(QBackendNode)
     explicit QBackendNode(QBackendNodePrivate &dd);
-    Q3D_DECL_DEPRECATED void notifyObservers(const QSceneChangePtr &e);
-    Q3D_DECL_DEPRECATED QNodeCommand::CommandId sendCommand(const QString &name, const QVariant &data,
-                                                          QNodeCommand::CommandId replyTo = QNodeCommand::CommandId());
-    Q3D_DECL_DEPRECATED void sendReply(const QNodeCommandPtr &command);
-    Q3D_DECL_DEPRECATED virtual void sceneChangeEvent(const QSceneChangePtr &e);
 
     QBackendNodePrivate *d_ptr;
 
 private:
     Q_DISABLE_COPY(QBackendNode)
     void setPeerId(QNodeId id) Q_DECL_NOEXCEPT;
-    Q3D_DECL_DEPRECATED virtual void initializeFromPeer(const QNodeCreatedChangeBasePtr &change);
 
-    friend class QBackendNodePropertyChange;
     friend class QAbstractAspectPrivate;
 #if defined(QT_BUILD_INTERNAL)
     friend class QBackendNodeTester;
diff --git a/src/core/nodes/qbackendnode_p.h b/src/core/nodes/qbackendnode_p.h
index 260eef087..8a4e4c57c 100644
--- a/src/core/nodes/qbackendnode_p.h
+++ b/src/core/nodes/qbackendnode_p.h
@@ -53,10 +53,6 @@
 
 #include <Qt3DCore/qbackendnode.h>
 #include <Qt3DCore/qnodeid.h>
-
-#include <Qt3DCore/private/qlockableobserverinterface_p.h>
-#include <Qt3DCore/private/qobservableinterface_p.h>
-#include <Qt3DCore/private/qobserverinterface_p.h>
 #include <Qt3DCore/private/qt3dcore_global_p.h>
 
 QT_BEGIN_NAMESPACE
@@ -66,15 +62,10 @@ namespace Qt3DCore {
 class QNode;
 
 class Q_3DCORE_PRIVATE_EXPORT QBackendNodePrivate
-        : public QObserverInterface
-        , public QObservableInterface
 {
 public:
     QBackendNodePrivate(QBackendNode::Mode mode);
 
-    void setArbiter(QLockableObserverInterface *arbiter) override;
-    void notifyObservers(const QSceneChangePtr &e) override;
-    void sceneChangeEvent(const QSceneChangePtr &e) override;
     void setEnabled(bool enabled);
 
     static QBackendNodePrivate *get(QBackendNode *n);
@@ -83,7 +74,6 @@ public:
     QBackendNode *q_ptr;
     QBackendNode::Mode m_mode;
 
-    QLockableObserverInterface *m_arbiter;
     QNodeId m_peerId;
     bool m_enabled;
 
diff --git a/src/core/nodes/qentity.cpp b/src/core/nodes/qentity.cpp
index 1199dfc4b..ac07faaef 100644
--- a/src/core/nodes/qentity.cpp
+++ b/src/core/nodes/qentity.cpp
@@ -41,7 +41,6 @@
 #include "qentity_p.h"
 
 #include <Qt3DCore/qcomponent.h>
-#include <Qt3DCore/qnodecreatedchange.h>
 #include <QtCore/QMetaObject>
 #include <QtCore/QMetaProperty>
 
@@ -144,7 +143,7 @@ void QEntityPrivate::removeDestroyedComponent(QComponent *comp)
     Q_CHECK_PTR(comp);
     qCDebug(Nodes) << Q_FUNC_INFO << comp;
 
-    updateNode(comp, nullptr, ComponentRemoved);
+    updateComponentRelationShip(comp, ComponentRelationshipChange::Removed);
     m_components.removeOne(comp);
 
     // Remove bookkeeping connection
@@ -223,7 +222,7 @@ void QEntity::addComponent(QComponent *comp)
     // Ensures proper bookkeeping
     d->registerPrivateDestructionHelper(comp, &QEntityPrivate::removeDestroyedComponent);
 
-    d->updateNode(comp, nullptr, ComponentAdded);
+    d->updateComponentRelationShip(comp, ComponentRelationshipChange::Added);
     static_cast<QComponentPrivate *>(QComponentPrivate::get(comp))->addEntity(this);
 }
 
@@ -238,7 +237,7 @@ void QEntity::removeComponent(QComponent *comp)
 
     static_cast<QComponentPrivate *>(QComponentPrivate::get(comp))->removeEntity(this);
 
-    d->updateNode(comp, nullptr, ComponentRemoved);
+    d->updateComponentRelationShip(comp, ComponentRelationshipChange::Removed);
 
     d->m_components.removeOne(comp);
 
@@ -294,35 +293,17 @@ QString QEntityPrivate::dumpSceneGraph() const
     return dumpSG(q).join('\n');
 }
 
-QNodeCreatedChangeBasePtr QEntity::createNodeCreationChange() const
+void QEntityPrivate::updateComponentRelationShip(QComponent *component, ComponentRelationshipChange::RelationShip change)
 {
-    auto creationChange = QNodeCreatedChangePtr<QEntityData>::create(this);
-    auto &data = creationChange->data;
-
-    Q_D(const QEntity);
-    data.parentEntityId = parentEntity() ? parentEntity()->id() : Qt3DCore::QNodeId();
-
-    // Find all child entities
-    QQueue<QNode *> queue;
-    queue.append(childNodes().toList());
-    data.childEntityIds.reserve(queue.size());
-    while (!queue.isEmpty()) {
-        auto *child = queue.dequeue();
-        auto *childEntity = qobject_cast<QEntity *>(child);
-        if (childEntity != nullptr)
-            data.childEntityIds.push_back(childEntity->id());
-        else
-            queue.append(child->childNodes().toList());
+    if (m_changeArbiter) {
+        // Ensure node has its postConstructorInit called if we reach this
+        // point, we could otherwise endup referencing a node that has yet
+        // to be created in the backend
+        QNodePrivate::get(component)->_q_ensureBackendNodeCreated();
+
+        Q_Q(QEntity);
+        m_changeArbiter->addDirtyEntityComponentNodes(q, component, change);
     }
-
-    data.componentIdsAndTypes.reserve(d->m_components.size());
-    const QComponentVector &components = d->m_components;
-    for (QComponent *c : components) {
-        const auto idAndType = QNodeIdTypePair(c->id(), QNodePrivate::findStaticMetaObject(c->metaObject()));
-        data.componentIdsAndTypes.push_back(idAndType);
-    }
-
-    return creationChange;
 }
 
 void QEntity::onParentChanged(QObject *)
diff --git a/src/core/nodes/qentity.h b/src/core/nodes/qentity.h
index 62398faa1..ab87da4eb 100644
--- a/src/core/nodes/qentity.h
+++ b/src/core/nodes/qentity.h
@@ -88,8 +88,6 @@ private Q_SLOTS:
 
 private:
     Q_DECLARE_PRIVATE(QEntity)
-
-    QNodeCreatedChangeBasePtr createNodeCreationChange() const override;
 };
 
 typedef QSharedPointer<QEntity> QEntityPtr;
diff --git a/src/core/nodes/qentity_p.h b/src/core/nodes/qentity_p.h
index 992f81931..d074148c1 100644
--- a/src/core/nodes/qentity_p.h
+++ b/src/core/nodes/qentity_p.h
@@ -55,6 +55,7 @@
 
 #include <Qt3DCore/private/qnode_p.h>
 #include <Qt3DCore/private/qt3dcore_global_p.h>
+#include <Qt3DCore/private/qchangearbiter_p.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -69,6 +70,7 @@ public :
     Q_DECLARE_PUBLIC(QEntity)
 
     QNodeId parentEntityId() const;
+    void updateComponentRelationShip(QComponent *component, ComponentRelationshipChange::RelationShip change);
 
     template<class T>
     QVector<T*> componentsOfType() const
diff --git a/src/core/nodes/qnode.cpp b/src/core/nodes/qnode.cpp
index ad084242f..918ce0827 100644
--- a/src/core/nodes/qnode.cpp
+++ b/src/core/nodes/qnode.cpp
@@ -43,12 +43,7 @@
 
 #include <Qt3DCore/QComponent>
 #include <Qt3DCore/qaspectengine.h>
-#include <Qt3DCore/qdynamicpropertyupdatedchange.h>
 #include <Qt3DCore/qentity.h>
-#include <Qt3DCore/qnodedestroyedchange.h>
-#include <Qt3DCore/qpropertynodeaddedchange.h>
-#include <Qt3DCore/qpropertynoderemovedchange.h>
-#include <Qt3DCore/qpropertyupdatedchange.h>
 #include <QtCore/QChildEvent>
 #include <QtCore/QEvent>
 #include <QtCore/QMetaObject>
@@ -57,7 +52,6 @@
 #include <Qt3DCore/private/corelogging_p.h>
 #include <Qt3DCore/private/qdestructionidandtypecollector_p.h>
 #include <Qt3DCore/private/qnodevisitor_p.h>
-#include <Qt3DCore/private/qpostman_p.h>
 #include <Qt3DCore/private/qscene_p.h>
 #include <Qt3DCore/private/qaspectengine_p.h>
 #include <Qt3DCore/private/qaspectmanager_p.h>
@@ -141,13 +135,6 @@ void QNodePrivate::notifyDestructionChangesAndRemoveFromScene()
 {
     Q_Q(QNode);
 
-    // We notify the backend that the parent lost us as a child
-    if (m_changeArbiter != nullptr && !m_parentId.isNull()) {
-        const auto change = QPropertyNodeRemovedChangePtr::create(m_parentId, q);
-        change->setPropertyName("children");
-        notifyObservers(change);
-    }
-
     // Tell the backend we are about to be destroyed
     if (m_hasBackendNode && m_scene && m_scene->engine())
         QAspectEnginePrivate::get(m_scene->engine())->removeNode(q);
@@ -238,9 +225,7 @@ void QNodePrivate::_q_addChild(QNode *childNode)
         // we need to catch that to avoid sending more than one new child event
         // to the backend.
         childD->m_notifiedParent = true;
-        const auto change = QPropertyNodeAddedChangePtr::create(m_id, childNode);
-        change->setPropertyName("children");
-        notifyObservers(change);
+        update();
     }
 
     // Update the scene
@@ -261,13 +246,7 @@ void QNodePrivate::_q_removeChild(QNode *childNode)
     Q_ASSERT_X(childNode->parent() == q_func(), Q_FUNC_INFO, "not a child of this node");
 
     QNodePrivate::get(childNode)->m_parentId = QNodeId();
-
-    // We notify the backend that we lost a child
-    if (m_changeArbiter != nullptr) {
-        const auto change = QPropertyNodeRemovedChangePtr::create(m_id, childNode);
-        change->setPropertyName("children");
-        notifyObservers(change);
-    }
+    update();
 }
 
 /*!
@@ -458,7 +437,7 @@ void QNodePrivate::addEntityComponentToScene(QNode *root)
     \internal
  */
 // Called in the main thread by QScene -> following QEvent::childAdded / addChild
-void QNodePrivate::setArbiter(QLockableObserverInterface *arbiter)
+void QNodePrivate::setArbiter(QChangeArbiter *arbiter)
 {
     if (m_changeArbiter && m_changeArbiter != arbiter) {
         unregisterNotifiedProperties();
@@ -467,7 +446,7 @@ void QNodePrivate::setArbiter(QLockableObserverInterface *arbiter)
         Q_Q(QNode);
         m_changeArbiter->removeDirtyFrontEndNode(q);
     }
-    m_changeArbiter = static_cast<QAbstractArbiter *>(arbiter);
+    m_changeArbiter = arbiter;
     if (m_changeArbiter)
         registerNotifiedProperties();
 }
@@ -523,53 +502,6 @@ void QNodePrivate::_q_ensureBackendNodeCreated()
 */
 
 /*!
- * Sends the \a change QSceneChangePtr to any QBackendNodes in the registered
- * aspects that correspond to this QNode.
- *
- * You only need to call this function if you wish to send a specific type of
- * change in place of the automatic handling.
- *
- * Note: as of Qt 5.14, change messages are deprecated and should not be used,
- * in particular for properties.
- */
-void QNode::notifyObservers(const QSceneChangePtr &change)
-{
-    Q_D(QNode);
-    d->notifyObservers(change);
-}
-
-/*!
-    \obsolete
-
-    Called when one or more backend aspects sends a notification \a change to the
-    current Qt3DCore::QNode instance.
-
-    \note This method should be reimplemented in your subclasses to properly
-    handle the \a change.
-*/
-void QNode::sceneChangeEvent(const QSceneChangePtr &change)
-{
-    Q_UNUSED(change)
-    if (change->type() == Qt3DCore::PropertyUpdated) {
-        // TODO: Do this more efficiently. We could pass the metaobject and property
-        //       index to the animation aspect via the QChannelMapping. This would
-        //       allow us to avoid the propertyIndex lookup here by sending them in
-        //       a new subclass of QPropertyUpdateChange.
-        // Try to find property and call setter
-        auto e = qSharedPointerCast<Qt3DCore::QPropertyUpdatedChange>(change);
-        const QMetaObject *mo = metaObject();
-        const int propertyIndex = mo->indexOfProperty(e->propertyName());
-        QMetaProperty mp = mo->property(propertyIndex);
-        bool wasBlocked = blockNotifications(true);
-        mp.write(this, e->value());
-        blockNotifications(wasBlocked);
-    } else {
-        // Nothing is handling this change, warn the user.
-        qWarning() << Q_FUNC_INFO << "sceneChangeEvent should have been subclassed";
-    }
-}
-
-/*!
     \internal
  */
 void QNodePrivate::setScene(QScene *scene)
@@ -618,25 +550,6 @@ void QNodePrivate::notifyDynamicPropertyChange(const QByteArray &name, const QVa
     update();
 }
 
-/*!
-    \internal
- */
-// Called by the main thread
-void QNodePrivate::notifyObservers(const QSceneChangePtr &change)
-{
-    Q_ASSERT(change);
-
-    // Don't send notifications if we are blocking
-    if (m_blockNotifications && change->type() == PropertyUpdated)
-        return;
-
-    if (m_changeArbiter != nullptr) {
-        QAbstractPostman *postman = m_changeArbiter->postman();
-        if (postman != nullptr)
-            postman->notifyBackend(change);
-    }
-}
-
 // Inserts this tree into the main Scene tree.
 // Needed when SceneLoaders provide a cloned tree from the backend
 // and need to insert it in the main scene tree
@@ -682,19 +595,6 @@ void QNodePrivate::update()
     }
 }
 
-void QNodePrivate::updateNode(QNode *node, const char *property, ChangeFlag change)
-{
-    if (m_changeArbiter) {
-        // Ensure node has its postConstructorInit called if we reach this
-        // point, we could otherwise endup referencing a node that has yet
-        // to be created in the backend
-        QNodePrivate::get(node)->_q_ensureBackendNodeCreated();
-
-        Q_Q(QNode);
-        m_changeArbiter->addDirtyFrontEndNode(q, node, property, change);
-    }
-}
-
 /*!
     \internal
  */
@@ -1000,21 +900,6 @@ void QNode::clearPropertyTrackings()
 }
 
 /*!
- * \obsolete
- */
-QNodeCreatedChangeBasePtr QNode::createNodeCreationChange() const
-{
-    // Uncomment this when implementing new frontend and backend types.
-    // Any classes that don't override this function will be noticeable here.
-    // Note that some classes actually don't need to override as they have
-    // no additional data to send. In those cases this default implementation
-    // is perfectly fine.
-    // const QMetaObject *mo = metaObject();
-    // qDebug() << Q_FUNC_INFO << mo->className();
-    return QNodeCreatedChangeBasePtr::create(this);
-}
-
-/*!
    \fn Qt3DCore::QNodeCommand::CommandId Qt3DCore::QNodeCommand::inReplyTo() const
 
    Returns the id of the original QNodeCommand message that
@@ -1052,52 +937,6 @@ QNodeCreatedChangeBasePtr QNode::createNodeCreationChange() const
 
     Erases all values that have been saved by the property tracking.
 */
-/*!
- * \brief Sends a command message to the backend node
- * \obsolete
- *
- * Creates a QNodeCommand message and dispatches it to the backend node. The
- * command is given and a \a name and some \a data which can be used in the
- * backend node to perform various operations.
- * This returns a CommandId which can be used to identify the initial command
- * when receiving a message in reply. If the command message is to be sent in
- * reply to another command, \a replyTo contains the id of that command.
- *
- * \sa QNodeCommand, QNode::sendReply
- */
-QNodeCommand::CommandId QNode::sendCommand(const QString &name,
-                                           const QVariant &data,
-                                           QNodeCommand::CommandId replyTo)
-{
-    Q_D(QNode);
-
-    // Bail out early, if we can, to avoid operator new
-    if (d->m_blockNotifications)
-        return QNodeCommand::CommandId(0);
-
-    auto e = QNodeCommandPtr::create(d->m_id);
-    e->setName(name);
-    e->setData(data);
-    e->setReplyToCommandId(replyTo);
-    d->notifyObservers(e);
-    return e->commandId();
-}
-
-/*!
- * \brief Send a \a command back to the backend node.
- * \obsolete
- *
- * Assumes the command is to be to sent back in reply to itself to the backend node.
- *
- * \sa QNodeCommand, QNode::sendCommand
- */
-void QNode::sendReply(const QNodeCommandPtr &command)
-{
-    Q_D(QNode);
-    command->setDeliveryFlags(QSceneChange::BackendNodes);
-    d->notifyObservers(command);
-}
-
 
 namespace {
 
diff --git a/src/core/nodes/qnode.h b/src/core/nodes/qnode.h
index efdec8da5..f24daf63f 100644
--- a/src/core/nodes/qnode.h
+++ b/src/core/nodes/qnode.h
@@ -40,10 +40,7 @@
 #ifndef QT3DCORE_QNODE_H
 #define QT3DCORE_QNODE_H
 
-#include <Qt3DCore/qnodecreatedchange.h>
 #include <Qt3DCore/qnodeid.h>
-#include <Qt3DCore/qnodecommand.h>
-#include <Qt3DCore/qscenechange.h>
 #include <Qt3DCore/qt3dcore_global.h>
 #include <QtCore/QObject>
 
@@ -99,10 +96,6 @@ public:
     void clearPropertyTracking(const QString &propertyName);
     void clearPropertyTrackings();
 
-    Q3D_DECL_DEPRECATED QNodeCommand::CommandId sendCommand(const QString &name, const QVariant &data = QVariant(),
-                                                          QNodeCommand::CommandId replyTo = QNodeCommand::CommandId());
-    Q3D_DECL_DEPRECATED void sendReply(const QNodeCommandPtr &command);
-
 public Q_SLOTS:
     void setParent(QNode *parent);
     void setEnabled(bool isEnabled);
@@ -116,12 +109,9 @@ Q_SIGNALS:
 
 protected:
     explicit QNode(QNodePrivate &dd, QNode *parent = nullptr);
-    Q3D_DECL_DEPRECATED void notifyObservers(const QSceneChangePtr &change);
-    Q3D_DECL_DEPRECATED virtual void sceneChangeEvent(const QSceneChangePtr &change);
 
 private:
     Q_DECLARE_PRIVATE(QNode)
-    Q3D_DECL_DEPRECATED virtual QNodeCreatedChangeBasePtr createNodeCreationChange() const;
 
     // We only want setParent(QNode *) to be callable
     // when dealing with QNode objects
@@ -135,8 +125,6 @@ private:
     friend class QAspectEngine;
     friend class QAspectEnginePrivate;
     friend class QAbstractAspectPrivate;
-    friend class QNodeCreatedChangeGenerator;
-    friend class QPostman;
     friend class QScene;
 
 #if defined(QT_BUILD_INTERNAL)
diff --git a/src/core/nodes/qnode_p.h b/src/core/nodes/qnode_p.h
index 5aa4c5328..907f0062a 100644
--- a/src/core/nodes/qnode_p.h
+++ b/src/core/nodes/qnode_p.h
@@ -57,7 +57,6 @@
 
 #include <Qt3DCore/private/propertychangehandler_p.h>
 #include <Qt3DCore/private/qchangearbiter_p.h>
-#include <Qt3DCore/private/qobservableinterface_p.h>
 #include <Qt3DCore/private/qt3dcore_global_p.h>
 #include <QtCore/private/qobject_p.h>
 #include <QQueue>
@@ -69,7 +68,7 @@ namespace Qt3DCore {
 class QNode;
 class QAspectEngine;
 
-class Q_3DCORE_PRIVATE_EXPORT QNodePrivate : public QObjectPrivate, public QObservableInterface
+class Q_3DCORE_PRIVATE_EXPORT QNodePrivate : public QObjectPrivate
 {
 public:
     QNodePrivate();
@@ -80,26 +79,21 @@ public:
     virtual void setScene(QScene *scene);
     QScene *scene() const;
 
-    void setArbiter(QLockableObserverInterface *arbiter) override;
+    void setArbiter(QChangeArbiter *arbiter);
 
     void notifyPropertyChange(const char *name, const QVariant &value);
     void notifyDynamicPropertyChange(const QByteArray &name, const QVariant &value);
-    void notifyObservers(const QSceneChangePtr &change) override;
 
     void insertTree(QNode *treeRoot, int depth = 0);
     void updatePropertyTrackMode();
 
     void update();
-    QT_WARNING_PUSH
-    QT_WARNING_DISABLE_DEPRECATED
-    void updateNode(QNode *node, const char* property, ChangeFlag change);
-    QT_WARNING_POP
 
     Q_DECLARE_PUBLIC(QNode)
 
     // For now this just protects access to the m_changeArbiter.
     // Later on we may decide to extend support for multiple observers.
-    QAbstractArbiter *m_changeArbiter;
+    QChangeArbiter *m_changeArbiter;
     QMetaObject *m_typeInfo;
     QScene *m_scene;
     mutable QNodeId m_id;
diff --git a/src/core/nodes/qnodecreatedchangegenerator.cpp b/src/core/nodes/qnodecreatedchangegenerator.cpp
deleted file mode 100644
index d91949fb1..000000000
--- a/src/core/nodes/qnodecreatedchangegenerator.cpp
+++ /dev/null
@@ -1,53 +0,0 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 Klaralvdalens Datakonsult AB (KDAB).
-** Contact: http://www.qt-project.org/legal
-**
-** This file is part of the Qt3D module of the Qt Toolkit.
-**
-** $QT_BEGIN_LICENSE:LGPL3$
-** 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 The Qt Company. For licensing terms
-** and conditions see http://www.qt.io/terms-conditions. For further
-** information use the contact form at http://www.qt.io/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 3 as published by the Free Software
-** Foundation and appearing in the file LICENSE.LGPLv3 included in the
-** packaging of this file. Please review the following information to
-** ensure the GNU Lesser General Public License version 3 requirements
-** will be met: https://www.gnu.org/licenses/lgpl.html.
-**
-** GNU General Public License Usage
-** Alternatively, this file may be used under the terms of the GNU
-** General Public License version 2.0 or later 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 2.0 requirements will be
-** met: http://www.gnu.org/licenses/gpl-2.0.html.
-**
-** $QT_END_LICENSE$
-**
-****************************************************************************/
-
-#include "qnodecreatedchangegenerator_p.h"
-
-#include <Qt3DCore/private/qnodevisitor_p.h>
-
-QT_BEGIN_NAMESPACE
-
-namespace Qt3DCore {
-
-QNodeCreatedChangeGenerator::QNodeCreatedChangeGenerator(QNode *rootNode)
-{
-    QNodeVisitor visitor;
-    visitor.traverse(rootNode, this, &QNodeCreatedChangeGenerator::createCreationChange);
-}
-
-} // namespace Qt3DCore
-
-QT_END_NAMESPACE
diff --git a/src/core/nodes/qnodecreatedchangegenerator_p.h b/src/core/nodes/qnodecreatedchangegenerator_p.h
deleted file mode 100644
index 35e5b673e..000000000
--- a/src/core/nodes/qnodecreatedchangegenerator_p.h
+++ /dev/null
@@ -1,97 +0,0 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 Klaralvdalens Datakonsult AB (KDAB).
-** Contact: http://www.qt-project.org/legal
-**
-** This file is part of the Qt3D module of the Qt Toolkit.
-**
-** $QT_BEGIN_LICENSE:LGPL3$
-** 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 The Qt Company. For licensing terms
-** and conditions see http://www.qt.io/terms-conditions. For further
-** information use the contact form at http://www.qt.io/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 3 as published by the Free Software
-** Foundation and appearing in the file LICENSE.LGPLv3 included in the
-** packaging of this file. Please review the following information to
-** ensure the GNU Lesser General Public License version 3 requirements
-** will be met: https://www.gnu.org/licenses/lgpl.html.
-**
-** GNU General Public License Usage
-** Alternatively, this file may be used under the terms of the GNU
-** General Public License version 2.0 or later 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 2.0 requirements will be
-** met: http://www.gnu.org/licenses/gpl-2.0.html.
-**
-** $QT_END_LICENSE$
-**
-****************************************************************************/
-
-#ifndef QT3DCORE_QNODECREATEDCHANGEGENERATOR_H
-#define QT3DCORE_QNODECREATEDCHANGEGENERATOR_H
-
-//
-//  W A R N I N G
-//  -------------
-//
-// This file is not part of the Qt API.  It exists for the convenience
-// of other Qt classes.  This header file may change from version to
-// version without notice, or even be removed.
-//
-// We mean it.
-//
-
-#include <Qt3DCore/qnode.h>
-#include <Qt3DCore/qnodecreatedchange.h>
-#include <Qt3DCore/qt3dcore_global.h>
-#include <QtCore/qvector.h>
-
-#include <Qt3DCore/private/qnode_p.h>
-
-QT_BEGIN_NAMESPACE
-
-namespace Qt3DCore {
-
-class Q_3DCORE_PRIVATE_EXPORT QNodeCreatedChangeGenerator
-{
-public:
-    QNodeCreatedChangeGenerator(QNode *rootNode);
-
-    QVector<QNodeCreatedChangeBasePtr> creationChanges() const { return m_creationChanges; }
-
-private:
-    void createCreationChange(QNode *node)
-    {
-        QT_WARNING_PUSH
-        QT_WARNING_DISABLE_DEPRECATED
-        const auto creationChange = node->createNodeCreationChange();
-        m_creationChanges.push_back(creationChange);
-
-        // Store the metaobject of the node in the QNode so that we have it available
-        // to us during destruction in the QNode destructor. This allows us to send
-        // the QNodeId and the metaobject as typeinfo to the backend aspects so they
-        // in turn can find the correct QBackendNodeMapper object to handle the destruction
-        // of the corresponding backend nodes.
-        QNodePrivate *d = QNodePrivate::get(node);
-        d->m_typeInfo = const_cast<QMetaObject*>(creationChange->metaObject());
-
-        // Mark this node as having been handled for creation so that it is picked up
-        d->m_hasBackendNode = true;
-        QT_WARNING_POP
-    }
-
-    QVector<QNodeCreatedChangeBasePtr> m_creationChanges;
-};
-
-} // namespace Qt3DCore
-
-QT_END_NAMESPACE
-
-#endif // QT3DCORE_QNODECREATEDCHANGEGENERATOR_H