FrameGraphItems are observed for changes

The Backend FrameGraphNode observe when needed the frontend FrameGraphItem for
SceneChange notifications. This is the case when the camera property of a
CameraSelector is updated to reference another camera. This is also the case
for the Viewport rectangle which could be updated.

Will have to check later for TechniqueFilter/RenderPassFilter

Change-Id: Iaf592f6b2496790a11b05111def5d3af473a1e84
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>

11 files changed, 123 insertions, 13 deletions

diff --git a/src/render/backend/framegraph/cameraselectornode.cpp b/src/render/backend/framegraph/cameraselectornode.cpp
index 5d10d5ad0..a3e2cdcf3 100644
--- a/src/render/backend/framegraph/cameraselectornode.cpp
+++ b/src/render/backend/framegraph/cameraselectornode.cpp
@@ -40,20 +40,55 @@
 ****************************************************************************/
 
 #include "cameraselectornode.h"
-
 #include "rendercamera.h"
+#include <Qt3DRenderer/cameraselector.h>
+#include <Qt3DRenderer/renderer.h>
+#include <Qt3DRenderer/rendereraspect.h>
+#include <Qt3DCore/qaspectmanager.h>
+#include <Qt3DCore/entity.h>
+#include "renderlogging.h"
 
 QT_BEGIN_NAMESPACE
 
 namespace Qt3D {
+
 namespace Render {
 
 CameraSelector::CameraSelector(FrameGraphNode *parent)
     : FrameGraphNode(FrameGraphNode::CameraSelector, parent)
+    , m_renderer(Q_NULLPTR)
+    , m_peer(Q_NULLPTR)
+{
+}
+
+void CameraSelector::setRenderer(Renderer *renderer)
 {
+    m_renderer = renderer;
 }
 
+void CameraSelector::setPeer(Qt3D::CameraSelector *peer)
+{
+    if (m_peer != peer) {
+        if (m_peer)
+            m_renderer->rendererAspect()->aspectManager()->changeArbiter()->unregisterObserver(this, m_peer);
+        m_peer = peer;
+        if (m_peer)
+            m_renderer->rendererAspect()->aspectManager()->changeArbiter()->registerObserver(this, m_peer, ComponentUpdated);
+    }
 }
+
+void CameraSelector::sceneChangeEvent(const QSceneChangePtr &e)
+{
+    qCDebug(Render::Framegraph) << Q_FUNC_INFO;
+    if (e->m_type == ComponentUpdated) {
+        QScenePropertyChangePtr propertyChange = qSharedPointerCast<QScenePropertyChange>(e);
+        if (propertyChange->m_propertyName == QByteArrayLiteral("camera"))
+            setCameraEntity(qobject_cast<Entity*>(propertyChange->m_value.value<Node*>()));
+    }
 }
 
+} // Render
+
+} // Qt3D
+
 QT_END_NAMESPACE
diff --git a/src/render/backend/framegraph/cameraselectornode.h b/src/render/backend/framegraph/cameraselectornode.h
index e39e42a8b..911634df6 100644
--- a/src/render/backend/framegraph/cameraselectornode.h
+++ b/src/render/backend/framegraph/cameraselectornode.h
@@ -49,21 +49,32 @@ QT_BEGIN_NAMESPACE
 namespace Qt3D {
 
 class Entity;
+class CameraSelector;
 
 namespace Render {
 
+class Renderer;
+
 class RenderCamera;
 
-class CameraSelector : public FrameGraphNode
+class CameraSelector : public FrameGraphNode, public QObserverInterface
 {
 public:
     CameraSelector(FrameGraphNode *parent = 0);
 
+    void setRenderer(Renderer *renderer);
+    void setPeer(Qt3D::CameraSelector *peer);
+    Qt3D::CameraSelector *peer() const { return m_peer; }
+
     void setCameraEntity(Entity *cameraEntity) { m_cameraEntity = cameraEntity; }
     Entity *cameraEntity() const { return m_cameraEntity; }
+    void sceneChangeEvent(const QSceneChangePtr &e) Q_DECL_OVERRIDE;
 
 private:
     Entity *m_cameraEntity;
+    Renderer *m_renderer;
+    Qt3D::CameraSelector *m_peer;
+
 };
 
 } // namespace Render
diff --git a/src/render/backend/framegraph/framegraphnode.h b/src/render/backend/framegraph/framegraphnode.h
index 6916c47a2..adf5de19c 100644
--- a/src/render/backend/framegraph/framegraphnode.h
+++ b/src/render/backend/framegraph/framegraphnode.h
@@ -44,6 +44,7 @@
 
 #include <qglobal.h>
 #include <QVector>
+#include <Qt3DCore/qchangearbiter.h>
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/render/backend/framegraph/viewportnode.cpp b/src/render/backend/framegraph/viewportnode.cpp
index 1150e3e6b..7fe9a47a5 100644
--- a/src/render/backend/framegraph/viewportnode.cpp
+++ b/src/render/backend/framegraph/viewportnode.cpp
@@ -40,7 +40,10 @@
 ****************************************************************************/
 
 #include "viewportnode.h"
-
+#include <Qt3DRenderer/renderer.h>
+#include <Qt3DRenderer/rendereraspect.h>
+#include <Qt3DCore/qaspectmanager.h>
+#include <Qt3DRenderer/viewport.h>
 #include <QDebug>
 
 QT_BEGIN_NAMESPACE
@@ -50,6 +53,8 @@ namespace Render {
 
 ViewportNode::ViewportNode(FrameGraphNode *parent)
     : FrameGraphNode(FrameGraphNode::Viewport, parent)
+    , m_renderer(Q_NULLPTR)
+    , m_peer(Q_NULLPTR)
     , m_xMin(0.0f)
     , m_yMin(0.0f)
     , m_xMax(1.0f)
@@ -57,6 +62,22 @@ ViewportNode::ViewportNode(FrameGraphNode *parent)
 {
 }
 
+void ViewportNode::setRenderer(Renderer *renderer)
+{
+    m_renderer = renderer;
+}
+
+void ViewportNode::setPeer(Qt3D::Viewport *peer)
+{
+    if (m_peer != peer) {
+        if (m_peer)
+            m_renderer->rendererAspect()->aspectManager()->changeArbiter()->unregisterObserver(this, m_peer);
+        m_peer = peer;
+        if (m_peer)
+            m_renderer->rendererAspect()->aspectManager()->changeArbiter()->registerObserver(this, m_peer, ComponentUpdated);
+    }
+}
+
 float ViewportNode::xMin() const
 {
     return m_xMin;
@@ -94,7 +115,22 @@ void ViewportNode::setYMax(float yMax)
     m_yMax = yMax;
 }
 
+void ViewportNode::sceneChangeEvent(const QSceneChangePtr &e)
+{
+    if (e->m_type == ComponentUpdated) {
+        QScenePropertyChangePtr propertyChange = qSharedPointerCast<QScenePropertyChange>(e);
+        if (propertyChange->m_propertyName == QByteArrayLiteral("rect")) {
+            QRectF rect = propertyChange->m_value.value<QRectF>();
+            setXMin(rect.x());
+            setYMin(rect.y());
+            setXMax(rect.width());
+            setYMax(rect.height());
+        }
+    }
+}
+
 } // Render
+
 } // Qt3D
 
 QT_END_NAMESPACE
diff --git a/src/render/backend/framegraph/viewportnode.h b/src/render/backend/framegraph/viewportnode.h
index f6a315b80..2f034c489 100644
--- a/src/render/backend/framegraph/viewportnode.h
+++ b/src/render/backend/framegraph/viewportnode.h
@@ -47,13 +47,22 @@
 QT_BEGIN_NAMESPACE
 
 namespace Qt3D {
+
+class Viewport;
+
 namespace Render {
 
-class ViewportNode : public Render::FrameGraphNode
+class Renderer;
+
+class ViewportNode : public Render::FrameGraphNode, public QObserverInterface
 {
 public:
     ViewportNode(Render::FrameGraphNode *parent = 0);
 
+    void setRenderer(Renderer *renderer);
+    void setPeer(Qt3D::Viewport *peer);
+    Qt3D::Viewport *peer() const { return m_peer; }
+
     float xMin() const;
     void setXMin(float xMin);
 
@@ -66,15 +75,21 @@ public:
     float yMax() const;
     void setYMax(float yMax);
 
+    void sceneChangeEvent(const QSceneChangePtr &e) Q_DECL_OVERRIDE;
+
 private:
+    Renderer *m_renderer;
+    Qt3D::Viewport *m_peer;
     float m_xMin;
     float m_yMin;
     float m_xMax;
     float m_yMax;
+
 };
 
-}
-}
+} // Render
+
+} // Qt3D
 
 QT_END_NAMESPACE
 
diff --git a/src/render/backend/renderscenebuilder.cpp b/src/render/backend/renderscenebuilder.cpp
index b28f17ab3..adbe751f3 100644
--- a/src/render/backend/renderscenebuilder.cpp
+++ b/src/render/backend/renderscenebuilder.cpp
@@ -157,7 +157,8 @@ Render::FrameGraphNode *RenderSceneBuilder::backendFrameGraphNode(Node *block)
     else if (qobject_cast<Qt3D::Viewport*>(block) != Q_NULLPTR) {
         Qt3D::Viewport *viewport = qobject_cast<Qt3D::Viewport*>(block);
         Render::ViewportNode *viewportNode = new Render::ViewportNode();
-
+        viewportNode->setRenderer(m_renderer);
+        viewportNode->setPeer(viewport);
         qCDebug(Backend) << Q_FUNC_INFO << "Viewport";
         viewportNode->setXMin(viewport->rect().x());
         viewportNode->setXMax(viewport->rect().width());
@@ -176,7 +177,8 @@ Render::FrameGraphNode *RenderSceneBuilder::backendFrameGraphNode(Node *block)
     else if (qobject_cast<Qt3D::CameraSelector*>(block) != Q_NULLPTR) {
         Qt3D::CameraSelector *cameraSelector = qobject_cast<Qt3D::CameraSelector*>(block);
         Render::CameraSelector *cameraSelectorNode = new Render::CameraSelector();
-
+        cameraSelectorNode->setRenderer(m_renderer);
+        cameraSelectorNode->setPeer(cameraSelector);
         Entity *cameraEntity = qobject_cast<Entity*>(cameraSelector->camera());
         // If the Entity is declared inline on the QML Side, the Entity is not set as part of the Scene tree
         // So we need to make sure the RenderNode for the given Entity exists in the RenderNodesMananger
diff --git a/src/render/frontend/cameraselector.h b/src/render/frontend/cameraselector.h
index 61d9cbdd4..1ad07dc9c 100644
--- a/src/render/frontend/cameraselector.h
+++ b/src/render/frontend/cameraselector.h
@@ -81,6 +81,10 @@ public:
         if (d->m_camera != camera) {
           d->m_camera = camera;
           emit cameraChanged();
+          QScenePropertyChangePtr propertyChange(new QScenePropertyChange(ComponentUpdated, this));
+          propertyChange->m_propertyName = QByteArrayLiteral("camera");
+          propertyChange->m_value = QVariant::fromValue(d->m_camera);
+          notifyObservers(propertyChange);
         }
     }
 
diff --git a/src/render/frontend/framegraphitem.cpp b/src/render/frontend/framegraphitem.cpp
index 522e449b2..606cf3c84 100644
--- a/src/render/frontend/framegraphitem.cpp
+++ b/src/render/frontend/framegraphitem.cpp
@@ -59,7 +59,8 @@ QT_BEGIN_NAMESPACE
 namespace Qt3D {
 
 FrameGraphItem::FrameGraphItem()
-    : d_ptr(new FrameGraphItemPrivate(this))
+    : QObservable()
+    , d_ptr(new FrameGraphItemPrivate(this))
 {
 }
 
diff --git a/src/render/frontend/framegraphitem.h b/src/render/frontend/framegraphitem.h
index 3a8239022..6e304bb6b 100644
--- a/src/render/frontend/framegraphitem.h
+++ b/src/render/frontend/framegraphitem.h
@@ -44,6 +44,7 @@
 
 #include <Qt3DRenderer/qt3drenderer_global.h>
 #include <Qt3DCore/node.h>
+#include <Qt3DCore/qchangearbiter.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -51,7 +52,7 @@ namespace Qt3D {
 
 class FrameGraphItemPrivate;
 
-class QT3DRENDERERSHARED_EXPORT FrameGraphItem
+class QT3DRENDERERSHARED_EXPORT FrameGraphItem : public QObservable
 {
 public:
     FrameGraphItem();
diff --git a/src/render/frontend/viewport.h b/src/render/frontend/viewport.h
index 50877d1f2..3c5fa39a7 100644
--- a/src/render/frontend/viewport.h
+++ b/src/render/frontend/viewport.h
@@ -66,8 +66,8 @@ public :
 class QT3DRENDERERSHARED_EXPORT Viewport : public FrameGraphItem
 {
 public:
-    Viewport() :
-        d_ptr(new ViewportPrivate(this))
+    Viewport()
+        : d_ptr(new ViewportPrivate(this))
     {}
 
     virtual ~Viewport() {}
@@ -84,6 +84,10 @@ public:
         if (rect != d->m_rect) {
             d->m_rect = rect;
             emit rectChanged();
+            QScenePropertyChangePtr propertyChange(new QScenePropertyChange(ComponentUpdated, this));
+            propertyChange->m_propertyName = QByteArrayLiteral("rect");
+            propertyChange->m_value = QVariant::fromValue(d->m_rect);
+            notifyObservers(propertyChange);
         }
     }
 
diff --git a/src/render/renderlogging.cpp b/src/render/renderlogging.cpp
index 5d0815163..c17c011ad 100644
--- a/src/render/renderlogging.cpp
+++ b/src/render/renderlogging.cpp
@@ -51,7 +51,7 @@ Q_LOGGING_CATEGORY(Backend, "Qt3D.Render.Backend")
 Q_LOGGING_CATEGORY(Frontend, "Qt3D.Render.Frontend")
 Q_LOGGING_CATEGORY(Io, "Qt3D.Render.IO")
 Q_LOGGING_CATEGORY(Jobs, "Qt3D.Render.Jobs")
-Q_LOGGING_CATEGORY(FrameGraph, "Qt3D.Render.FrameGraph")
+Q_LOGGING_CATEGORY(Framegraph, "Qt3D.Render.Framegraph")
 Q_LOGGING_CATEGORY(RenderNodes, "Qt3D.Render.RenderNodes")
 Q_LOGGING_CATEGORY(Rendering, "Qt3D.Render.Rendering")