1 files changed, 35 insertions, 2 deletions
diff --git a/src/location/declarativemaps/qdeclarativegeomap.cpp b/src/location/declarativemaps/qdeclarativegeomap.cpp
index 167f1d5f..17baf811 100644
--- a/src/location/declarativemaps/qdeclarativegeomap.cpp
+++ b/src/location/declarativemaps/qdeclarativegeomap.cpp
@@ -198,7 +198,7 @@ QDeclarativeGeoMap::QDeclarativeGeoMap(QQuickItem *parent)
     setAcceptHoverEvents(false);
     setAcceptedMouseButtons(Qt::LeftButton);
     setFlags(QQuickItem::ItemHasContents | QQuickItem::ItemClipsChildrenToShape);
-    setFiltersChildMouseEvents(true);
+    setFiltersChildMouseEvents(true); // needed for childMouseEventFilter to work.
 
     m_activeMapType = new QDeclarativeGeoMapType(QGeoMapType(QGeoMapType::NoMap,
                                                              tr("No Map"),
@@ -707,7 +707,8 @@ void QDeclarativeGeoMap::mappingManagerInitialized()
         emit m_map->copyrightsChanged(copyrightImage);
 
 
-    connect(m_map.data(), &QGeoMap::sgNodeChanged, this, &QQuickItem::update);
+    connect(window(), &QQuickWindow::beforeSynchronizing, this, &QDeclarativeGeoMap::updateItemToWindowTransform, Qt::DirectConnection);
+    connect(m_map.data(), &QGeoMap::sgNodeChanged, this, &QDeclarativeGeoMap::onSGNodeChanged);
     connect(m_map.data(), &QGeoMap::cameraCapabilitiesChanged, this, &QDeclarativeGeoMap::onCameraCapabilitiesChanged);
 
     // This prefetches a buffer around the map
@@ -2179,6 +2180,38 @@ bool QDeclarativeGeoMap::removeMapItemView_real(QDeclarativeGeoMapItemView *item
     return removeMapItemGroup_real(itemView); // at this point, all delegate instances have been removed.
 }
 
+void QDeclarativeGeoMap::updateItemToWindowTransform()
+{
+    if (!m_initialized)
+        return;
+
+    // Update itemToWindowTransform into QGeoProjection
+    const QTransform item2WindowOld = m_map->geoProjection().itemToWindowTransform();
+    QTransform item2Window = QQuickItemPrivate::get(this)->itemToWindowTransform();
+    if (!property("layer").isNull() && property("layer").value<QObject *>()->property("enabled").toBool())
+        item2Window.reset(); // When layer is enabled, the item is rendered offscreen with no transformation, then the layer is applied
+
+    m_map->setItemToWindowTransform(item2Window);
+
+    // This method is called at every redraw, including those redraws not generated by
+    // sgNodeChanged.
+    // In these cases, *if* the item2windowTransform has changed (e.g., if transformation of
+    // the item or one of its ancestors changed), a forced update of the map items using accelerated
+    // GL implementation has to be performed in order to have them pulling the updated itemToWindowTransform.
+    if (!m_sgNodeHasChanged && item2WindowOld != item2Window) {
+        for (auto i: qAsConst(m_mapItems))
+            i->setMaterialDirty();
+    }
+
+    m_sgNodeHasChanged = false;
+}
+
+void QDeclarativeGeoMap::onSGNodeChanged()
+{
+    m_sgNodeHasChanged = true;
+    update();
+}
+
 /*!
     \qmlmethod void QtLocation::Map::addMapItemView(MapItemView itemView)