QMesh: add a status property

This will allow to monitor the loading of the mesh.

Change-Id: I52ad7a7d556c64bfdb04173be932d6fe79bf5ae2
Task-number: QTBUG-60927
Reviewed-by: Mike Krus <mike.krus@kdab.com>

3 files changed, 70 insertions, 3 deletions

diff --git a/src/render/geometry/qmesh.cpp b/src/render/geometry/qmesh.cpp
index 834284547..6df06d723 100644
--- a/src/render/geometry/qmesh.cpp
+++ b/src/render/geometry/qmesh.cpp
@@ -71,6 +71,7 @@ Q_GLOBAL_STATIC_WITH_ARGS(QFactoryLoader, geometryLoader, (QGeometryLoaderFactor
 
 QMeshPrivate::QMeshPrivate()
     : QGeometryRendererPrivate()
+    , m_status(QMesh::None)
 {
 }
 
@@ -93,6 +94,17 @@ void QMeshPrivate::updateFunctor()
         q->setGeometryFactory(QGeometryFactoryPtr(new MeshLoaderFunctor(q, engine)));
 }
 
+void QMeshPrivate::setStatus(QMesh::Status status)
+{
+    if (m_status != status) {
+        Q_Q(QMesh);
+        m_status = status;
+        const bool wasBlocked = q->blockNotifications(true);
+        emit q->statusChanged(status);
+        q->blockNotifications(wasBlocked);
+    }
+}
+
 /*!
  * \qmltype Mesh
  * \instantiates Qt3DRender::QMesh
@@ -138,6 +150,25 @@ void QMeshPrivate::updateFunctor()
  */
 
 /*!
+    \enum QMesh::Status
+
+    This enum identifies the status of shader used.
+
+    \value None              A source mesh hasn't been assigned a source yet
+    \value Loading           The mesh geometry is loading
+    \value Ready             The mesh geometry was successfully loaded
+    \value Error             An error occurred while loading the mesh
+*/
+
+/*!
+    \qmlproperty enumeration Mesh::status
+
+    Holds the status of the mesh loading.
+    \sa Qt3DRender::QMesh::Status
+    \readonly
+ */
+
+/*!
  * \class Qt3DRender::QMesh
  * \inheaderfile Qt3DRender/QMesh
  * \inmodule Qt3DRender
@@ -186,6 +217,17 @@ QMesh::QMesh(QMeshPrivate &dd, QNode *parent)
 {
 }
 
+/*! \internal */
+void QMesh::sceneChangeEvent(const Qt3DCore::QSceneChangePtr &change)
+{
+    Q_D(QMesh);
+    if (change->type() == Qt3DCore::PropertyUpdated) {
+        const Qt3DCore::QPropertyUpdatedChangePtr e = qSharedPointerCast<Qt3DCore::QPropertyUpdatedChange>(change);
+        if (e->propertyName() == QByteArrayLiteral("status"))
+            d->setStatus(e->value().value<QMesh::Status>());
+    }
+}
+
 void QMesh::setSource(const QUrl& source)
 {
     Q_D(QMesh);
@@ -233,6 +275,18 @@ QString QMesh::meshName() const
 }
 
 /*!
+    \property QMesh::status
+
+    Holds the status of the mesh loading.
+    \sa Qt3DRender::QMesh::Status
+ */
+QMesh::Status QMesh::status() const
+{
+    Q_D(const QMesh);
+    return d->m_status;
+}
+
+/*!
  * \internal
  */
 MeshLoaderFunctor::MeshLoaderFunctor(QMesh *mesh, Qt3DCore::QAspectEngine *engine, const QByteArray &sourceData)
diff --git a/src/render/geometry/qmesh.h b/src/render/geometry/qmesh.h
index 51fdab63a..a7b2747f7 100644
--- a/src/render/geometry/qmesh.h
+++ b/src/render/geometry/qmesh.h
@@ -59,13 +59,23 @@ class QT3DRENDERSHARED_EXPORT QMesh : public QGeometryRenderer
     Q_OBJECT
     Q_PROPERTY(QUrl source READ source WRITE setSource NOTIFY sourceChanged)
     Q_PROPERTY(QString meshName READ meshName WRITE setMeshName NOTIFY meshNameChanged)
-
+    Q_PROPERTY(Status status READ status NOTIFY statusChanged REVISION 11)
 public:
     explicit QMesh(Qt3DCore::QNode *parent = nullptr);
     ~QMesh();
 
+    enum Status {
+        None = 0,
+        Loading,
+        Ready,
+        Error
+    };
+    Q_ENUM(Status) // LCOV_EXCL_LINE
+
+
     QUrl source() const;
     QString meshName() const;
+    Status status() const;
 
 public Q_SLOTS:
     void setSource(const QUrl &source);
@@ -74,9 +84,11 @@ public Q_SLOTS:
 Q_SIGNALS:
     void sourceChanged(const QUrl &source);
     void meshNameChanged(const QString &meshName);
+    void statusChanged(Status status);
 
 protected:
     explicit QMesh(QMeshPrivate &dd, Qt3DCore::QNode *parent = nullptr);
+    void sceneChangeEvent(const Qt3DCore::QSceneChangePtr &change) override;
 
 private:
     Q_DECLARE_PRIVATE(QMesh)
diff --git a/src/render/geometry/qmesh_p.h b/src/render/geometry/qmesh_p.h
index e8eccb608..76fc351a8 100644
--- a/src/render/geometry/qmesh_p.h
+++ b/src/render/geometry/qmesh_p.h
@@ -54,14 +54,13 @@
 #include <Qt3DCore/private/qdownloadhelperservice_p.h>
 #include <Qt3DRender/private/qgeometryrenderer_p.h>
 #include <Qt3DRender/private/qt3drender_global_p.h>
+#include <Qt3DRender/qmesh.h>
 #include <QUrl>
 
 QT_BEGIN_NAMESPACE
 
 namespace Qt3DRender {
 
-class QMesh;
-
 class QT3DRENDERSHARED_PRIVATE_EXPORT QMeshPrivate : public QGeometryRendererPrivate
 {
 public:
@@ -72,9 +71,11 @@ public:
 
     void setScene(Qt3DCore::QScene *scene) override;
     void updateFunctor();
+    void setStatus(QMesh::Status status);
 
     QUrl m_source;
     QString m_meshName;
+    QMesh::Status m_status;
 };
 
 class Q_AUTOTEST_EXPORT MeshDownloadRequest : public Qt3DCore::QDownloadRequest