QTBUG47714 Workaround

src/qml/timeline/Clip.qml

@@ -137,6 +137,7 @@ Rectangle {
 
     Canvas {
         id: transitionCanvas
+        Component.onCompleted: view.applyQTBUG47714Workaround(transitionCanvas);
         visible: isTransition
         anchors.fill: parent
         onPaint: {
@@ -162,6 +163,7 @@ Rectangle {
 
     Canvas {
         id: waveform
+        Component.onCompleted: view.applyQTBUG47714Workaround(waveform);
         visible: !isBlank && settings.timelineShowWaveforms
         height: isAudio? parent.height : parent.height / 2
         anchors.left: parent.left
@@ -302,6 +304,7 @@ Rectangle {
 
     Canvas {
         id: fadeInCanvas
+        Component.onCompleted: view.applyQTBUG47714Workaround(fadeInCanvas);
         visible: !isBlank && !isTransition
         width: parent.fadeIn * timeScale
         height: parent.height - parent.border.width * 2
@@ -398,6 +401,7 @@ Rectangle {
 
     Canvas {
         id: fadeOutCanvas
+        Component.onCompleted: view.applyQTBUG47714Workaround(fadeOutCanvas);
         visible: !isBlank && !isTransition
         width: parent.fadeOut * timeScale
         height: parent.height - parent.border.width * 2

src/qml/timeline/timeline.qml

@@ -281,6 +281,7 @@ Rectangle {
             }
             Canvas {
                 id: playhead
+                Component.onCompleted: view.applyQTBUG47714Workaround(playhead);
                 visible: timeline.position > -1
                 x: timeline.position * multitrack.scaleFactor - scrollView.flickableItem.contentX - 5
                 y: 0

src/qmltypes/qmlview.cpp

@@ -19,6 +19,14 @@
 #include "qmlview.h"
 #include <QQuickView>
 #include <QDebug>
+#include <QSGMaterial>
+#include <QSGSimpleTextureNode>
+
+#include <QTimer>
+
+#include <private/qquickitem_p.h>
+#include <private/qsgrenderer_p.h>
+#include <private/qquickcanvasitem_p.h>
 
 QmlView::QmlView(QQuickView* qview)
     : QObject(qview)
@@ -30,3 +38,73 @@ QPoint QmlView::pos()
 {
     return m_qview->mapToGlobal(QPoint(0,0));
 }
+
+class QTBUG47714WorkaroundRenderListener : public QObject
+{
+public:
+    QTBUG47714WorkaroundRenderListener(QQuickItem * item)
+        : item(item)
+        , oldTexture(0)
+    {
+        startTimer(0);
+    }
+
+    void timerEvent(QTimerEvent * event)
+    {
+        if (item) {
+            QQuickWindow * window = item->window();
+            connect(window, &QQuickWindow::beforeSynchronizing,
+                    this, &QTBUG47714WorkaroundRenderListener::beforeSync);
+            connect(window, &QQuickWindow::afterSynchronizing,
+                    this, &QTBUG47714WorkaroundRenderListener::afterSync);
+        }
+        killTimer(event->timerId());
+    }
+
+    QSGSimpleTextureNode * nodeFromItem()
+    {
+        if (item.isNull())
+        {
+            deleteLater();
+            return 0;
+        }
+        QQuickItemPrivate * priv = QQuickItemPrivate::get(item);
+        QSGTransformNode * tnode = priv->itemNode();
+        QSGGeometryNode * geom = 0;
+        if (tnode->firstChild()->type() == QSGNode::GeometryNodeType)
+            geom = static_cast<QSGGeometryNode*>(tnode->firstChild());
+        else if (tnode->firstChild()->type() == QSGNode::OpacityNodeType
+                && tnode->firstChild()->firstChild()
+                && tnode->firstChild()->firstChild()->type() == QSGNode::GeometryNodeType)
+            geom = static_cast<QSGGeometryNode*>(tnode->firstChild()->firstChild());
+
+        return dynamic_cast<QSGSimpleTextureNode*>(geom);
+    }
+
+
+    void beforeSync()
+    {
+        QSGSimpleTextureNode * texNode = nodeFromItem();
+        if (texNode)
+            texNode->setOwnsTexture(false);
+    }
+
+    void afterSync()
+    {
+        QSGSimpleTextureNode * texNode = nodeFromItem();
+        if (texNode) {
+            oldTexture = texNode->texture();
+        } else {
+            delete oldTexture;
+            oldTexture = 0;
+        }
+    }
+
+    QPointer<QQuickItem> item;
+    QSGTexture * oldTexture;
+};
+
+void QmlView::applyQTBUG47714Workaround(QObject * item)
+{
+    new QTBUG47714WorkaroundRenderListener(static_cast<QQuickItem*>(item));
+}

src/qmltypes/qmlview.h

@@ -32,6 +32,7 @@ class QmlView : public QObject
 public:
     explicit QmlView(QQuickView* qview);
     QPoint pos();
+    Q_INVOKABLE void applyQTBUG47714Workaround(QObject * item);
 
 private:
     QQuickView* m_qview;

src/src.pro

@@ -2,6 +2,7 @@ CONFIG   += link_prl
 
 QT       += widgets opengl xml network printsupport qml quick sql webkitwidgets
 QT       += multimedia
+QT       += qml-private core-private quick-private gui-private
 
 TARGET = shotcut
 TEMPLATE = app