Update QBuffer to use sync updating

Change-Id: I3a48156b6e9303842ff0670295d28e36d1ff8a9e
Reviewed-by: Paul Lemire <paul.lemire@kdab.com>

11 files changed, 159 insertions, 202 deletions

diff --git a/src/render/frontend/qrenderaspect.cpp b/src/render/frontend/qrenderaspect.cpp
index c61298c62..1e8535a3c 100644
--- a/src/render/frontend/qrenderaspect.cpp
+++ b/src/render/frontend/qrenderaspect.cpp
@@ -267,7 +267,7 @@ void QRenderAspectPrivate::registerBackendTypes()
 
     // Geometry + Compute
     q->registerBackendType<QAttribute>(QSharedPointer<Render::NodeFunctor<Render::Attribute, Render::AttributeManager> >::create(m_renderer));
-    q->registerBackendType<QBuffer>(QSharedPointer<Render::BufferFunctor>::create(m_renderer, m_nodeManagers->bufferManager()));
+    q->registerBackendType<QBuffer, true>(QSharedPointer<Render::BufferFunctor>::create(m_renderer, m_nodeManagers->bufferManager()));
     q->registerBackendType<QComputeCommand>(QSharedPointer<Render::NodeFunctor<Render::ComputeCommand, Render::ComputeCommandManager> >::create(m_renderer));
     q->registerBackendType<QGeometry>(QSharedPointer<Render::NodeFunctor<Render::Geometry, Render::GeometryManager> >::create(m_renderer));
     q->registerBackendType<QGeometryRenderer, true>(QSharedPointer<Render::GeometryRendererFunctor>::create(m_renderer, m_nodeManagers->geometryRendererManager()));
diff --git a/src/render/geometry/buffer.cpp b/src/render/geometry/buffer.cpp
index d60f89c7d..998db3640 100644
--- a/src/render/geometry/buffer.cpp
+++ b/src/render/geometry/buffer.cpp
@@ -113,28 +113,6 @@ void Buffer::updateDataFromGPUToCPU(QByteArray data)
     notifyObservers(e);
 }
 
-void Buffer::initializeFromPeer(const Qt3DCore::QNodeCreatedChangeBasePtr &change)
-{
-    const auto typedChange = qSharedPointerCast<Qt3DCore::QNodeCreatedChange<QBufferData>>(change);
-    const auto &data = typedChange->data;
-    m_data = data.data;
-    m_usage = data.usage;
-    m_syncData = data.syncData;
-    m_access = data.access;
-    m_bufferDirty = true;
-
-    if (!m_data.isEmpty())
-        forceDataUpload();
-
-    m_functor = data.functor;
-    Q_ASSERT(m_manager);
-    if (m_functor)
-        m_manager->addDirtyBuffer(peerId());
-
-    m_manager->addBufferReference(peerId());
-    markDirty(AbstractRenderer::BuffersDirty);
-}
-
 void Buffer::forceDataUpload()
 {
     // We push back an update with offset = -1
@@ -145,40 +123,50 @@ void Buffer::forceDataUpload()
     m_bufferUpdates.push_back(updateNewData);
 }
 
-void Buffer::sceneChangeEvent(const Qt3DCore::QSceneChangePtr &e)
+void Buffer::syncFromFrontEnd(const QNode *frontEnd, bool firstTime)
 {
-    if (e->type() == PropertyUpdated) {
-        QPropertyUpdatedChangePtr propertyChange = qSharedPointerCast<QPropertyUpdatedChange>(e);
-        QByteArray propertyName = propertyChange->propertyName();
-        if (propertyName == QByteArrayLiteral("data")) {
-            QByteArray newData = propertyChange->value().toByteArray();
+    BackendNode::syncFromFrontEnd(frontEnd, firstTime);
+    const QBuffer *node = qobject_cast<const QBuffer *>(frontEnd);
+    if (!node)
+        return;
+
+    if (firstTime && m_manager != nullptr)
+        m_manager->addBufferReference(peerId());
+
+    m_syncData = node->isSyncData();
+    m_access = node->accessType();
+    if (m_usage != node->usage()) {
+        m_usage = node->usage();
+        m_bufferDirty = true;
+    }
+    {
+        QBufferDataGeneratorPtr newGenerator = node->dataGenerator();
+        bool dirty = (newGenerator && m_functor && !(*newGenerator == *m_functor)) ||
+                     (newGenerator.isNull() && !m_functor.isNull()) ||
+                     (!newGenerator.isNull() && m_functor.isNull());
+        m_bufferDirty |= dirty;
+        m_functor = newGenerator;
+        if (m_functor && m_manager != nullptr)
+            m_manager->addDirtyBuffer(peerId());
+    }
+    {
+        QVariant v = node->property("QT3D_updateData");
+        if (v.isValid()) {
+            Qt3DRender::QBufferUpdate updateData = v.value<Qt3DRender::QBufferUpdate>();
+            m_data.replace(updateData.offset, updateData.data.size(), updateData.data);
+            m_bufferUpdates.push_back(updateData);
+            m_bufferDirty = true;
+            const_cast<QBuffer *>(node)->setProperty("QT3D_updateData", {});
+        } else {
+            QByteArray newData = node->data();
             bool dirty = m_data != newData;
             m_bufferDirty |= dirty;
             m_data = newData;
-            if (dirty)
+            if (dirty && !m_data.isEmpty())
                 forceDataUpload();
-        } else if (propertyName == QByteArrayLiteral("updateData")) {
-            Qt3DRender::QBufferUpdate updateData = propertyChange->value().value<Qt3DRender::QBufferUpdate>();
-            m_data.replace(updateData.offset, updateData.data.size(), updateData.data);
-            m_bufferUpdates.push_back(updateData);
-            m_bufferDirty = true;
-        } else if (propertyName == QByteArrayLiteral("usage")) {
-            m_usage = static_cast<QBuffer::UsageType>(propertyChange->value().value<int>());
-            m_bufferDirty = true;
-        } else if (propertyName == QByteArrayLiteral("accessType")) {
-            m_access = static_cast<QBuffer::AccessType>(propertyChange->value().value<int>());
-        } else if (propertyName == QByteArrayLiteral("dataGenerator")) {
-            QBufferDataGeneratorPtr newGenerator = propertyChange->value().value<QBufferDataGeneratorPtr>();
-            m_bufferDirty |= !(newGenerator && m_functor && *newGenerator == *m_functor);
-            m_functor = newGenerator;
-            if (m_functor && m_manager != nullptr)
-                m_manager->addDirtyBuffer(peerId());
-        } else if (propertyName == QByteArrayLiteral("syncData")) {
-            m_syncData = propertyChange->value().toBool();
         }
-        markDirty(AbstractRenderer::BuffersDirty);
     }
-    BackendNode::sceneChangeEvent(e);
+    markDirty(AbstractRenderer::BuffersDirty);
 }
 
 // Called by Renderer once the buffer has been uploaded to OpenGL
diff --git a/src/render/geometry/buffer_p.h b/src/render/geometry/buffer_p.h
index 9a171599d..a3f52d1b3 100644
--- a/src/render/geometry/buffer_p.h
+++ b/src/render/geometry/buffer_p.h
@@ -73,7 +73,7 @@ public:
     ~Buffer();
     void cleanup();
 
-    void sceneChangeEvent(const Qt3DCore::QSceneChangePtr &e) override;
+    void syncFromFrontEnd(const Qt3DCore::QNode *frontEnd, bool firstTime) override;
 
     void setManager(BufferManager *manager);
     void executeFunctor();
@@ -88,7 +88,6 @@ public:
     void unsetDirty();
 
 private:
-    void initializeFromPeer(const Qt3DCore::QNodeCreatedChangeBasePtr &change) final;
     void forceDataUpload();
 
     QBuffer::UsageType m_usage;
diff --git a/src/render/geometry/qbuffer.cpp b/src/render/geometry/qbuffer.cpp
index e0574a4c5..f27005f2b 100644
--- a/src/render/geometry/qbuffer.cpp
+++ b/src/render/geometry/qbuffer.cpp
@@ -329,7 +329,7 @@ void QBuffer::setData(const QByteArray &bytes)
     Q_D(QBuffer);
     if (bytes != d->m_data) {
         d->m_data = bytes;
-        Qt3DCore::QNodePrivate::get(this)->notifyPropertyChange("data", QVariant::fromValue(d->m_data));
+        Qt3DCore::QNodePrivate::get(this)->update();
         emit dataChanged(bytes);
     }
 }
@@ -351,11 +351,8 @@ void QBuffer::updateData(int offset, const QByteArray &bytes)
     QBufferUpdate updateData;
     updateData.offset = offset;
     updateData.data = bytes;
-
-    auto e = QPropertyUpdatedChangePtr::create(id());
-    e->setPropertyName("updateData");
-    e->setValue(QVariant::fromValue(updateData));
-    notifyObservers(e);
+    setProperty("QT3D_updateData", QVariant::fromValue(updateData));
+    d->update();
 }
 
 /*!
@@ -409,12 +406,7 @@ void QBuffer::setDataGenerator(const QBufferDataGeneratorPtr &functor)
     if (functor && d->m_functor && *functor == *d->m_functor)
         return;
     d->m_functor = functor;
-    if (d->m_changeArbiter != nullptr) {
-        auto change = QPropertyUpdatedChangePtr::create(d->m_id);
-        change->setPropertyName("dataGenerator");
-        change->setValue(QVariant::fromValue(d->m_functor));
-        d->notifyObservers(change);
-    }
+    d->update();
 }
 
 /*!
diff --git a/tests/auto/render/boundingsphere/tst_boundingsphere.cpp b/tests/auto/render/boundingsphere/tst_boundingsphere.cpp
index df804c260..e1b01cd13 100644
--- a/tests/auto/render/boundingsphere/tst_boundingsphere.cpp
+++ b/tests/auto/render/boundingsphere/tst_boundingsphere.cpp
@@ -314,13 +314,13 @@ private Q_SLOTS:
         Qt3DRender::Render::Buffer *vbufferBackend = test->nodeManagers()->bufferManager()->getOrCreateResource(vbuffer->id());
         vbufferBackend->setRenderer(test->renderer());
         vbufferBackend->setManager(test->nodeManagers()->bufferManager());
-        simulateInitialization(vbuffer, vbufferBackend);
+        simulateInitializationSync(vbuffer, vbufferBackend);
 
         ibuffer->setData(idata);
         Qt3DRender::Render::Buffer *ibufferBackend = test->nodeManagers()->bufferManager()->getOrCreateResource(ibuffer->id());
         ibufferBackend->setRenderer(test->renderer());
         ibufferBackend->setManager(test->nodeManagers()->bufferManager());
-        simulateInitialization(ibuffer, ibufferBackend);
+        simulateInitializationSync(ibuffer, ibufferBackend);
 
         Qt3DRender::QGeometry *g = new Qt3DRender::QGeometry;
         for (int i = 0; i < 2; ++i)
@@ -426,7 +426,7 @@ private Q_SLOTS:
         Qt3DRender::Render::Buffer *vbufferBackend = test->nodeManagers()->bufferManager()->getOrCreateResource(vbuffer->id());
         vbufferBackend->setRenderer(test->renderer());
         vbufferBackend->setManager(test->nodeManagers()->bufferManager());
-        simulateInitialization(vbuffer, vbufferBackend);
+        simulateInitializationSync(vbuffer, vbufferBackend);
 
         Qt3DRender::QGeometry *g = new Qt3DRender::QGeometry;
         g->addAttribute(new Qt3DRender::QAttribute);
diff --git a/tests/auto/render/buffer/tst_buffer.cpp b/tests/auto/render/buffer/tst_buffer.cpp
index da853d4e9..1487d3728 100644
--- a/tests/auto/render/buffer/tst_buffer.cpp
+++ b/tests/auto/render/buffer/tst_buffer.cpp
@@ -65,6 +65,7 @@ private:
 class tst_RenderBuffer : public Qt3DCore::QBackendNodeTester
 {
     Q_OBJECT
+
 private Q_SLOTS:
 
     void checkPeerPropertyMirroring()
@@ -82,7 +83,7 @@ private Q_SLOTS:
         // WHEN
         renderBuffer.setRenderer(&renderer);
         renderBuffer.setManager(&bufferManager);
-        simulateInitialization(&buffer, &renderBuffer);
+        simulateInitializationSync(&buffer, &renderBuffer);
 
         // THEN
         QCOMPARE(renderBuffer.peerId(), buffer.id());
@@ -98,170 +99,154 @@ private Q_SLOTS:
     void checkInitialAndCleanedUpState()
     {
         // GIVEN
-        Qt3DRender::Render::Buffer renderBuffer;
+        Qt3DRender::Render::Buffer backendBuffer;
         Qt3DRender::Render::BufferManager bufferManager;
         TestRenderer renderer;
 
         // THEN
-        QCOMPARE(renderBuffer.isDirty(), false);
-        QCOMPARE(renderBuffer.usage(), Qt3DRender::QBuffer::StaticDraw);
-        QVERIFY(renderBuffer.data().isEmpty());
-        QVERIFY(renderBuffer.peerId().isNull());
-        QVERIFY(renderBuffer.dataGenerator().isNull());
-        QVERIFY(renderBuffer.pendingBufferUpdates().empty());
+        QCOMPARE(backendBuffer.isDirty(), false);
+        QCOMPARE(backendBuffer.usage(), Qt3DRender::QBuffer::StaticDraw);
+        QVERIFY(backendBuffer.data().isEmpty());
+        QVERIFY(backendBuffer.peerId().isNull());
+        QVERIFY(backendBuffer.dataGenerator().isNull());
+        QVERIFY(backendBuffer.pendingBufferUpdates().empty());
 
         // GIVEN
-        Qt3DRender::QBuffer buffer;
-        buffer.setUsage(Qt3DRender::QBuffer::DynamicCopy);
-        buffer.setData(QByteArrayLiteral("C7"));
-        buffer.setDataGenerator(Qt3DRender::QBufferDataGeneratorPtr(new TestFunctor(73)));
+        Qt3DRender::QBuffer frontendBuffer;
+        frontendBuffer.setUsage(Qt3DRender::QBuffer::DynamicCopy);
+        frontendBuffer.setData(QByteArrayLiteral("C7KR4"));
+        frontendBuffer.setDataGenerator(Qt3DRender::QBufferDataGeneratorPtr(new TestFunctor(73)));
 
         // WHEN
-        renderBuffer.setManager(&bufferManager);
-        renderBuffer.setRenderer(&renderer);
-        simulateInitialization(&buffer, &renderBuffer);
+        backendBuffer.setManager(&bufferManager);
+        backendBuffer.setRenderer(&renderer);
+        simulateInitializationSync(&frontendBuffer, &backendBuffer);
 
-        Qt3DCore::QPropertyUpdatedChangePtr updateChange(new Qt3DCore::QPropertyUpdatedChange(Qt3DCore::QNodeId()));
-        Qt3DRender::QBufferUpdate updateData;
-        updateData.offset = 2;
-        updateData.data = QByteArrayLiteral("LS5");
-        updateChange->setValue(QVariant::fromValue(updateData));
-        updateChange->setPropertyName("updateData");
-        renderBuffer.sceneChangeEvent(updateChange);
+        frontendBuffer.updateData(2, QByteArrayLiteral("LS5"));
+        backendBuffer.syncFromFrontEnd(&frontendBuffer, false);
 
         // THEN
-        QCOMPARE(renderBuffer.usage(), Qt3DRender::QBuffer::DynamicCopy);
-        QCOMPARE(renderBuffer.isDirty(), true);
-        QCOMPARE(renderBuffer.data(), QByteArrayLiteral("C7LS5"));
-        QVERIFY(!renderBuffer.dataGenerator().isNull());
-        QVERIFY(!renderBuffer.pendingBufferUpdates().empty());
+        QCOMPARE(backendBuffer.usage(), Qt3DRender::QBuffer::DynamicCopy);
+        QCOMPARE(backendBuffer.isDirty(), true);
+        QCOMPARE(backendBuffer.data(), QByteArrayLiteral("C7LS5"));
+        QVERIFY(!backendBuffer.dataGenerator().isNull());
+        QVERIFY(!backendBuffer.pendingBufferUpdates().empty());
 
         // WHEN
-        renderBuffer.cleanup();
+        backendBuffer.cleanup();
 
         // THEN
-        QCOMPARE(renderBuffer.isDirty(), false);
-        QCOMPARE(renderBuffer.usage(), Qt3DRender::QBuffer::StaticDraw);
-        QVERIFY(renderBuffer.data().isEmpty());
-        QVERIFY(renderBuffer.dataGenerator().isNull());
-        QVERIFY(renderBuffer.pendingBufferUpdates().empty());
+        QCOMPARE(backendBuffer.isDirty(), false);
+        QCOMPARE(backendBuffer.usage(), Qt3DRender::QBuffer::StaticDraw);
+        QVERIFY(backendBuffer.data().isEmpty());
+        QVERIFY(backendBuffer.dataGenerator().isNull());
+        QVERIFY(backendBuffer.pendingBufferUpdates().empty());
     }
 
     void checkPropertyChanges()
     {
         // GIVEN
         TestRenderer renderer;
-        Qt3DRender::Render::Buffer renderBuffer;
-        renderBuffer.setRenderer(&renderer);
+        Qt3DRender::QBuffer frontendBuffer;
+        Qt3DRender::Render::Buffer backendBuffer;
+        backendBuffer.setRenderer(&renderer);
+        simulateInitializationSync(&frontendBuffer, &backendBuffer);
 
         // THEN
-        QVERIFY(renderBuffer.data().isEmpty());
-        QVERIFY(renderBuffer.usage() != Qt3DRender::QBuffer::DynamicRead);
-        QVERIFY(!renderBuffer.isDirty());
-        QVERIFY(!(renderer.dirtyBits() & Qt3DRender::Render::AbstractRenderer::BuffersDirty));
+        QVERIFY(backendBuffer.data().isEmpty());
+        QVERIFY(backendBuffer.usage() != Qt3DRender::QBuffer::DynamicRead);
+        QVERIFY(!backendBuffer.isDirty());
+        QVERIFY(renderer.dirtyBits() & Qt3DRender::Render::AbstractRenderer::BuffersDirty);
         renderer.clearDirtyBits(Qt3DRender::Render::AbstractRenderer::AllDirty);
 
         // WHEN
-        Qt3DCore::QPropertyUpdatedChangePtr updateChange(new Qt3DCore::QPropertyUpdatedChange(Qt3DCore::QNodeId()));
-        updateChange->setValue(static_cast<int>(Qt3DRender::QBuffer::DynamicRead));
-        updateChange->setPropertyName("usage");
-        renderBuffer.sceneChangeEvent(updateChange);
+        frontendBuffer.setUsage(Qt3DRender::QBuffer::DynamicRead);
+        backendBuffer.syncFromFrontEnd(&frontendBuffer, false);
 
         // THEN
-        QCOMPARE(renderBuffer.usage(), Qt3DRender::QBuffer::DynamicRead);
-        QVERIFY(renderBuffer.isDirty());
+        QCOMPARE(backendBuffer.usage(), Qt3DRender::QBuffer::DynamicRead);
+        QVERIFY(backendBuffer.isDirty());
 
         QVERIFY(renderer.dirtyBits() & Qt3DRender::Render::AbstractRenderer::BuffersDirty);
         renderer.clearDirtyBits(Qt3DRender::Render::AbstractRenderer::AllDirty);
 
-        renderBuffer.unsetDirty();
-        QVERIFY(!renderBuffer.isDirty());
+        backendBuffer.unsetDirty();
+        QVERIFY(!backendBuffer.isDirty());
 
         // WHEN
-        updateChange = QSharedPointer<Qt3DCore::QPropertyUpdatedChange>::create(Qt3DCore::QNodeId());
-        updateChange->setValue(QByteArrayLiteral("LS9"));
-        updateChange->setPropertyName("data");
-        renderBuffer.sceneChangeEvent(updateChange);
+        frontendBuffer.setData(QByteArrayLiteral("LS9SL"));
+        backendBuffer.syncFromFrontEnd(&frontendBuffer, false);
 
         // THEN
-        QCOMPARE(renderBuffer.data(), QByteArrayLiteral("LS9"));
-        QVERIFY(renderBuffer.isDirty());
-        QCOMPARE(renderBuffer.pendingBufferUpdates().size(), 1);
-        QCOMPARE(renderBuffer.pendingBufferUpdates().first().offset, -1);
+        QCOMPARE(backendBuffer.data(), QByteArrayLiteral("LS9SL"));
+        QVERIFY(backendBuffer.isDirty());
+        QCOMPARE(backendBuffer.pendingBufferUpdates().size(), 1);
+        QCOMPARE(backendBuffer.pendingBufferUpdates().first().offset, -1);
 
-        renderBuffer.pendingBufferUpdates().clear();
+        backendBuffer.pendingBufferUpdates().clear();
 
         QVERIFY(renderer.dirtyBits() & Qt3DRender::Render::AbstractRenderer::BuffersDirty);
         renderer.clearDirtyBits(Qt3DRender::Render::AbstractRenderer::AllDirty);
 
-        renderBuffer.unsetDirty();
-        QVERIFY(!renderBuffer.isDirty());
+        backendBuffer.unsetDirty();
+        QVERIFY(!backendBuffer.isDirty());
 
         // WHEN
         Qt3DRender::QBufferDataGeneratorPtr functor(new TestFunctor(355));
-        updateChange = QSharedPointer<Qt3DCore::QPropertyUpdatedChange>::create(Qt3DCore::QNodeId());
-        updateChange->setValue(QVariant::fromValue(functor));
-        updateChange->setPropertyName("dataGenerator");
-        renderBuffer.sceneChangeEvent(updateChange);
+        frontendBuffer.setDataGenerator(functor);
+        backendBuffer.syncFromFrontEnd(&frontendBuffer, false);
 
         // THEN
-        QCOMPARE(renderBuffer.dataGenerator(), functor);
-        QVERIFY(renderBuffer.isDirty());
+        QCOMPARE(backendBuffer.dataGenerator(), functor);
+        QVERIFY(backendBuffer.isDirty());
 
         QVERIFY(renderer.dirtyBits() & Qt3DRender::Render::AbstractRenderer::BuffersDirty);
         renderer.clearDirtyBits(Qt3DRender::Render::AbstractRenderer::AllDirty);
 
-        renderBuffer.unsetDirty();
-        QVERIFY(!renderBuffer.isDirty());
+        backendBuffer.unsetDirty();
+        QVERIFY(!backendBuffer.isDirty());
 
         // WHEN
-        updateChange = QSharedPointer<Qt3DCore::QPropertyUpdatedChange>::create(Qt3DCore::QNodeId());
-        updateChange->setValue(true);
-        updateChange->setPropertyName("syncData");
-        renderBuffer.sceneChangeEvent(updateChange);
+        frontendBuffer.setSyncData(true);
+        backendBuffer.syncFromFrontEnd(&frontendBuffer, false);
 
         // THEN
-        QCOMPARE(renderBuffer.isSyncData(), true);
-        QVERIFY(!renderBuffer.isDirty());
+        QCOMPARE(backendBuffer.isSyncData(), true);
+        QVERIFY(!backendBuffer.isDirty());
 
         QVERIFY(renderer.dirtyBits() & Qt3DRender::Render::AbstractRenderer::BuffersDirty);
         renderer.clearDirtyBits(Qt3DRender::Render::AbstractRenderer::AllDirty);
 
         // WHEN
         TestArbiter arbiter;
-        Qt3DCore::QBackendNodePrivate::get(&renderBuffer)->setArbiter(&arbiter);
-        renderBuffer.executeFunctor();
+        Qt3DCore::QBackendNodePrivate::get(&backendBuffer)->setArbiter(&arbiter);
+        backendBuffer.executeFunctor();
 
         // THEN
         QCOMPARE(arbiter.events.count(), 1);
         Qt3DCore::QPropertyUpdatedChangePtr change = arbiter.events.first().staticCast<Qt3DCore::QPropertyUpdatedChange>();
         QCOMPARE(change->propertyName(), "data");
         QCOMPARE(change->value().toByteArray(), QByteArrayLiteral("454"));
-        QCOMPARE(renderBuffer.pendingBufferUpdates().size(), 1);
-        QCOMPARE(renderBuffer.pendingBufferUpdates().first().offset, -1);
+        QCOMPARE(backendBuffer.pendingBufferUpdates().size(), 1);
+        QCOMPARE(backendBuffer.pendingBufferUpdates().first().offset, -1);
 
         arbiter.events.clear();
-        renderBuffer.pendingBufferUpdates().clear();
+        backendBuffer.pendingBufferUpdates().clear();
 
         // WHEN
-        updateChange = QSharedPointer<Qt3DCore::QPropertyUpdatedChange>::create(Qt3DCore::QNodeId());
-        Qt3DRender::QBufferUpdate updateData;
-        updateData.offset = 2;
-        updateData.data = QByteArrayLiteral("LS5");
-        updateChange->setValue(QVariant::fromValue(updateData));
-        updateChange->setPropertyName("updateData");
-        renderBuffer.sceneChangeEvent(updateChange);
+        frontendBuffer.updateData(2, QByteArrayLiteral("LS5"));
+        backendBuffer.syncFromFrontEnd(&frontendBuffer, false);
 
         // THEN
-        QVERIFY(!renderBuffer.pendingBufferUpdates().empty());
-        QCOMPARE(renderBuffer.pendingBufferUpdates().first().offset, 2);
-        QVERIFY(renderBuffer.isDirty());
+        QVERIFY(!backendBuffer.pendingBufferUpdates().empty());
+        QCOMPARE(backendBuffer.pendingBufferUpdates().first().offset, 2);
+        QVERIFY(backendBuffer.isDirty());
 
         QVERIFY(renderer.dirtyBits() & Qt3DRender::Render::AbstractRenderer::BuffersDirty);
         renderer.clearDirtyBits(Qt3DRender::Render::AbstractRenderer::AllDirty);
 
-        renderBuffer.unsetDirty();
-        QVERIFY(!renderBuffer.isDirty());
+        backendBuffer.unsetDirty();
+        QVERIFY(!backendBuffer.isDirty());
     }
 
     void checkBufferManagerReferenceCount()
@@ -275,7 +260,7 @@ private Q_SLOTS:
         // WHEN
         renderBuffer.setRenderer(&renderer);
         renderBuffer.setManager(&bufferManager);
-        simulateInitialization(&buffer, &renderBuffer);
+        simulateInitializationSync(&buffer, &renderBuffer);
 
         // THEN
         QVERIFY(bufferManager.takeBuffersToRelease().empty());
@@ -305,7 +290,7 @@ private Q_SLOTS:
         QCOMPARE(renderer.dirtyBits(), 0);
 
         // WHEN
-        simulateInitialization(&buffer, &renderBuffer);
+        simulateInitializationSync(&buffer, &renderBuffer);
 
         // THEN
         QCOMPARE(renderer.dirtyBits(), Qt3DRender::Render::AbstractRenderer::BuffersDirty);
diff --git a/tests/auto/render/coordinatereader/tst_coordinatereader.cpp b/tests/auto/render/coordinatereader/tst_coordinatereader.cpp
index 6f705dca1..7077e24a0 100644
--- a/tests/auto/render/coordinatereader/tst_coordinatereader.cpp
+++ b/tests/auto/render/coordinatereader/tst_coordinatereader.cpp
@@ -149,7 +149,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer.data(), backendBuffer);
+        simulateInitializationSync(dataBuffer.data(), backendBuffer);
 
         positionAttribute->setBuffer(dataBuffer.data());
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
@@ -232,7 +232,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer.data(), backendBuffer);
+        simulateInitializationSync(dataBuffer.data(), backendBuffer);
 
         positionAttribute->setBuffer(dataBuffer.data());
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
@@ -326,7 +326,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer.data(), backendBuffer);
+        simulateInitializationSync(dataBuffer.data(), backendBuffer);
 
         positionAttribute->setBuffer(dataBuffer.data());
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
@@ -415,7 +415,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer.data(), backendBuffer);
+        simulateInitializationSync(dataBuffer.data(), backendBuffer);
 
         positionAttribute->setBuffer(dataBuffer.data());
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
diff --git a/tests/auto/render/qbuffer/tst_qbuffer.cpp b/tests/auto/render/qbuffer/tst_qbuffer.cpp
index 8a9a25408..94c0a49cb 100644
--- a/tests/auto/render/qbuffer/tst_qbuffer.cpp
+++ b/tests/auto/render/qbuffer/tst_qbuffer.cpp
@@ -154,12 +154,10 @@ private Q_SLOTS:
         QCoreApplication::processEvents();
 
         // THEN
-        QCOMPARE(arbiter.events.size(), 1);
-        auto change = arbiter.events.first().staticCast<Qt3DCore::QPropertyUpdatedChange>();
-        QCOMPARE(change->propertyName(), "dataGenerator");
-        QCOMPARE(change->value().value<Qt3DRender::QBufferDataGeneratorPtr>(), functor);
+        QCOMPARE(arbiter.dirtyNodes.size(), 1);
+        QCOMPARE(arbiter.dirtyNodes.front(), buffer.data());
 
-        arbiter.events.clear();
+        arbiter.dirtyNodes.clear();
 
         // WHEN
         buffer->setSyncData(true);
@@ -176,13 +174,8 @@ private Q_SLOTS:
         QCoreApplication::processEvents();
 
         // THEN
-        QCOMPARE(arbiter.events.size(), 1);
-        QCOMPARE(buffer->data(), QByteArrayLiteral("ZL1"));
-        change = arbiter.events.first().staticCast<Qt3DCore::QPropertyUpdatedChange>();
-        QCOMPARE(change->propertyName(), "updateData");
-        Qt3DRender::QBufferUpdate updateData = change->value().value<Qt3DRender::QBufferUpdate>();
-        QCOMPARE(updateData.offset, 1);
-        QCOMPARE(updateData.data, QByteArrayLiteral("L1"));
+        QCOMPARE(arbiter.dirtyNodes.size(), 1);
+        QCOMPARE(arbiter.dirtyNodes.front(), buffer.data());
     }
 };
 
diff --git a/tests/auto/render/scene2d/tst_scene2d.cpp b/tests/auto/render/scene2d/tst_scene2d.cpp
index 1eaeee307..a0bbd20b1 100644
--- a/tests/auto/render/scene2d/tst_scene2d.cpp
+++ b/tests/auto/render/scene2d/tst_scene2d.cpp
@@ -276,7 +276,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer, backendBuffer);
+        simulateInitializationSync(dataBuffer, backendBuffer);
 
         positionAttribute->setBuffer(dataBuffer);
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
diff --git a/tests/auto/render/segmentvisitor/tst_segmentvisitor.cpp b/tests/auto/render/segmentvisitor/tst_segmentvisitor.cpp
index 02f4de64f..129844917 100644
--- a/tests/auto/render/segmentvisitor/tst_segmentvisitor.cpp
+++ b/tests/auto/render/segmentvisitor/tst_segmentvisitor.cpp
@@ -185,7 +185,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer.data(), backendBuffer);
+        simulateInitializationSync(dataBuffer.data(), backendBuffer);
 
         positionAttribute->setBuffer(dataBuffer.data());
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
@@ -254,7 +254,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer.data(), backendBuffer);
+        simulateInitializationSync(dataBuffer.data(), backendBuffer);
 
         QByteArray indexData;
         indexData.resize(sizeof(uint) * 2 * 5);
@@ -274,7 +274,7 @@ private Q_SLOTS:
         Buffer *backendIndexBuffer = nodeManagers->bufferManager()->getOrCreateResource(indexDataBuffer->id());
         backendIndexBuffer->setRenderer(&renderer);
         backendIndexBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(indexDataBuffer.data(), backendIndexBuffer);
+        simulateInitializationSync(indexDataBuffer.data(), backendIndexBuffer);
 
         positionAttribute->setBuffer(dataBuffer.data());
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
@@ -354,7 +354,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer.data(), backendBuffer);
+        simulateInitializationSync(dataBuffer.data(), backendBuffer);
 
         positionAttribute->setBuffer(dataBuffer.data());
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
@@ -423,7 +423,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer.data(), backendBuffer);
+        simulateInitializationSync(dataBuffer.data(), backendBuffer);
 
         QByteArray indexData;
         indexData.resize(sizeof(uint) * 2 * 4);
@@ -437,7 +437,7 @@ private Q_SLOTS:
         Buffer *backendIndexBuffer = nodeManagers->bufferManager()->getOrCreateResource(indexDataBuffer->id());
         backendIndexBuffer->setRenderer(&renderer);
         backendIndexBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(indexDataBuffer.data(), backendIndexBuffer);
+        simulateInitializationSync(indexDataBuffer.data(), backendIndexBuffer);
 
         positionAttribute->setBuffer(dataBuffer.data());
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
@@ -515,7 +515,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer.data(), backendBuffer);
+        simulateInitializationSync(dataBuffer.data(), backendBuffer);
 
         positionAttribute->setBuffer(dataBuffer.data());
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
@@ -585,7 +585,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer.data(), backendBuffer);
+        simulateInitializationSync(dataBuffer.data(), backendBuffer);
 
         QByteArray indexData;
         indexData.resize(sizeof(uint) * 2 * 4);
@@ -599,7 +599,7 @@ private Q_SLOTS:
         Buffer *backendIndexBuffer = nodeManagers->bufferManager()->getOrCreateResource(indexDataBuffer->id());
         backendIndexBuffer->setRenderer(&renderer);
         backendIndexBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(indexDataBuffer.data(), backendIndexBuffer);
+        simulateInitializationSync(indexDataBuffer.data(), backendIndexBuffer);
 
         positionAttribute->setBuffer(dataBuffer.data());
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
@@ -679,7 +679,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer.data(), backendBuffer);
+        simulateInitializationSync(dataBuffer.data(), backendBuffer);
 
         positionAttribute->setBuffer(dataBuffer.data());
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
@@ -747,7 +747,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer.data(), backendBuffer);
+        simulateInitializationSync(dataBuffer.data(), backendBuffer);
 
         QByteArray indexData;
         indexData.resize(sizeof(uint) * 4);
@@ -761,7 +761,7 @@ private Q_SLOTS:
         Buffer *backendIndexBuffer = nodeManagers->bufferManager()->getOrCreateResource(indexDataBuffer->id());
         backendIndexBuffer->setRenderer(&renderer);
         backendIndexBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(indexDataBuffer.data(), backendIndexBuffer);
+        simulateInitializationSync(indexDataBuffer.data(), backendIndexBuffer);
 
         positionAttribute->setBuffer(dataBuffer.data());
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
diff --git a/tests/auto/render/trianglevisitor/tst_trianglevisitor.cpp b/tests/auto/render/trianglevisitor/tst_trianglevisitor.cpp
index 6bd051029..5345a0ffc 100644
--- a/tests/auto/render/trianglevisitor/tst_trianglevisitor.cpp
+++ b/tests/auto/render/trianglevisitor/tst_trianglevisitor.cpp
@@ -187,7 +187,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer.data(), backendBuffer);
+        simulateInitializationSync(dataBuffer.data(), backendBuffer);
 
         positionAttribute->setBuffer(dataBuffer.data());
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
@@ -262,7 +262,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer.data(), backendBuffer);
+        simulateInitializationSync(dataBuffer.data(), backendBuffer);
 
         QByteArray indexData;
         indexData.resize(sizeof(uint) * 3 * 5);
@@ -287,7 +287,7 @@ private Q_SLOTS:
         Buffer *backendIndexBuffer = nodeManagers->bufferManager()->getOrCreateResource(indexDataBuffer->id());
         backendIndexBuffer->setRenderer(&renderer);
         backendIndexBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(indexDataBuffer.data(), backendIndexBuffer);
+        simulateInitializationSync(indexDataBuffer.data(), backendIndexBuffer);
 
         positionAttribute->setBuffer(dataBuffer.data());
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
@@ -374,7 +374,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer.data(), backendBuffer);
+        simulateInitializationSync(dataBuffer.data(), backendBuffer);
 
         positionAttribute->setBuffer(dataBuffer.data());
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
@@ -451,7 +451,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer.data(), backendBuffer);
+        simulateInitializationSync(dataBuffer.data(), backendBuffer);
 
         QByteArray indexData;
         indexData.resize(sizeof(uint) * 3 * 4);
@@ -473,7 +473,7 @@ private Q_SLOTS:
         Buffer *backendIndexBuffer = nodeManagers->bufferManager()->getOrCreateResource(indexDataBuffer->id());
         backendIndexBuffer->setRenderer(&renderer);
         backendIndexBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(indexDataBuffer.data(), backendIndexBuffer);
+        simulateInitializationSync(indexDataBuffer.data(), backendIndexBuffer);
 
         positionAttribute->setBuffer(dataBuffer.data());
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
@@ -563,7 +563,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer.data(), backendBuffer);
+        simulateInitializationSync(dataBuffer.data(), backendBuffer);
 
         positionAttribute->setBuffer(dataBuffer.data());
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
@@ -640,7 +640,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer.data(), backendBuffer);
+        simulateInitializationSync(dataBuffer.data(), backendBuffer);
 
         QByteArray indexData;
         indexData.resize(sizeof(uint) * 3 * 2);
@@ -656,7 +656,7 @@ private Q_SLOTS:
         Buffer *backendIndexBuffer = nodeManagers->bufferManager()->getOrCreateResource(indexDataBuffer->id());
         backendIndexBuffer->setRenderer(&renderer);
         backendIndexBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(indexDataBuffer.data(), backendIndexBuffer);
+        simulateInitializationSync(indexDataBuffer.data(), backendIndexBuffer);
 
         positionAttribute->setBuffer(dataBuffer.data());
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
@@ -742,7 +742,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer.data(), backendBuffer);
+        simulateInitializationSync(dataBuffer.data(), backendBuffer);
 
         positionAttribute->setBuffer(dataBuffer.data());
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
@@ -816,7 +816,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer.data(), backendBuffer);
+        simulateInitializationSync(dataBuffer.data(), backendBuffer);
 
         QByteArray indexData;
         indexData.resize(sizeof(uint) * 3 * 4);
@@ -839,7 +839,7 @@ private Q_SLOTS:
         Buffer *backendIndexBuffer = nodeManagers->bufferManager()->getOrCreateResource(indexDataBuffer->id());
         backendIndexBuffer->setRenderer(&renderer);
         backendIndexBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(indexDataBuffer.data(), backendIndexBuffer);
+        simulateInitializationSync(indexDataBuffer.data(), backendIndexBuffer);
 
         positionAttribute->setBuffer(dataBuffer.data());
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
@@ -936,7 +936,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer.data(), backendBuffer);
+        simulateInitializationSync(dataBuffer.data(), backendBuffer);
 
         positionAttribute->setBuffer(dataBuffer.data());
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
@@ -1012,7 +1012,7 @@ private Q_SLOTS:
         Buffer *backendBuffer = nodeManagers->bufferManager()->getOrCreateResource(dataBuffer->id());
         backendBuffer->setRenderer(&renderer);
         backendBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(dataBuffer.data(), backendBuffer);
+        simulateInitializationSync(dataBuffer.data(), backendBuffer);
 
         QByteArray indexData;
         indexData.resize(sizeof(uint) * 8);
@@ -1030,7 +1030,7 @@ private Q_SLOTS:
         Buffer *backendIndexBuffer = nodeManagers->bufferManager()->getOrCreateResource(indexDataBuffer->id());
         backendIndexBuffer->setRenderer(&renderer);
         backendIndexBuffer->setManager(nodeManagers->bufferManager());
-        simulateInitialization(indexDataBuffer.data(), backendIndexBuffer);
+        simulateInitializationSync(indexDataBuffer.data(), backendIndexBuffer);
 
         positionAttribute->setBuffer(dataBuffer.data());
         positionAttribute->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());