3 files changed, 97 insertions, 15 deletions

diff --git a/src/gui/graphicsview/qgraphicsitem.cpp b/src/gui/graphicsview/qgraphicsitem.cpp
index 9c0c649..5d11ec3 100644
--- a/src/gui/graphicsview/qgraphicsitem.cpp
+++ b/src/gui/graphicsview/qgraphicsitem.cpp
@@ -4830,25 +4830,17 @@ void QGraphicsItemPrivate::ensureSceneTransformRecursive(QGraphicsItem **topMost
         return; // Continue backtrack.
     }
 
+    // This item and all its descendants have dirty scene transforms.
+    // We're about to validate this item's scene transform, so we have to
+    // invalidate all the children; otherwise there's no way for the descendants
+    // to detect that the ancestor has changed.
+    invalidateChildrenSceneTransform();
+
     // COMBINE my transform with the parent's scene transform.
     updateSceneTransformFromParent();
     Q_ASSERT(!dirtySceneTransform);
 }
 
-void QGraphicsItemPrivate::ensureSceneTransform()
-{
-    if (dirtySceneTransform) {
-        // This item and all its descendants have dirty scene transforms.
-        // We're about to validate this item's scene transform, so we have to
-        // invalidate all the children; otherwise there's no way for the descendants
-        // to detect that the ancestor has changed.
-        invalidateChildrenSceneTransform();
-    }
-
-    QGraphicsItem *that = q_func();
-    ensureSceneTransformRecursive(&that);
-}
-
 /*!
     \internal
 */
diff --git a/src/gui/graphicsview/qgraphicsitem_p.h b/src/gui/graphicsview/qgraphicsitem_p.h
index b891de3..0b58ad3 100644
--- a/src/gui/graphicsview/qgraphicsitem_p.h
+++ b/src/gui/graphicsview/qgraphicsitem_p.h
@@ -318,7 +318,11 @@ public:
     void invalidateCachedClipPathRecursively(bool childrenOnly = false, const QRectF &emptyIfOutsideThisRect = QRectF());
     void updateCachedClipPathFromSetPosHelper(const QPointF &newPos);
     void ensureSceneTransformRecursive(QGraphicsItem **topMostDirtyItem);
-    void ensureSceneTransform();
+    inline void ensureSceneTransform()
+    {
+        QGraphicsItem *that = q_func();
+        ensureSceneTransformRecursive(&that);
+    }
 
     inline bool hasTranslateOnlySceneTransform()
     {
diff --git a/tests/auto/qgraphicsitem/tst_qgraphicsitem.cpp b/tests/auto/qgraphicsitem/tst_qgraphicsitem.cpp
index 5e8f4c4..c2acac9 100644
--- a/tests/auto/qgraphicsitem/tst_qgraphicsitem.cpp
+++ b/tests/auto/qgraphicsitem/tst_qgraphicsitem.cpp
@@ -293,6 +293,7 @@ private slots:
     void setActivePanelOnInactiveScene();
     void activationOnShowHide();
     void moveWhileDeleting();
+    void ensureDirtySceneTransform();
 
     // task specific tests below me
     void task141694_textItemEnsureVisible();
@@ -8156,5 +8157,90 @@ void tst_QGraphicsItem::moveWhileDeleting()
     delete rect;
 }
 
+class MyRectItem : public QGraphicsWidget
+{
+    Q_OBJECT
+public:
+    MyRectItem(QGraphicsItem *parent = 0) : QGraphicsWidget(parent)
+    {
+
+    }
+
+    void paint(QPainter *painter, const QStyleOptionGraphicsItem *, QWidget *)
+    {
+        painter->setBrush(brush);
+        painter->drawRect(boundingRect());
+    }
+
+public slots :
+    void move()
+    {
+        setPos(-100,-100);
+        topLevel->collidingItems(Qt::IntersectsItemBoundingRect);
+    }
+public:
+    QGraphicsItem *topLevel;
+    QBrush brush;
+};
+
+
+void tst_QGraphicsItem::ensureDirtySceneTransform()
+{
+    QGraphicsScene scene;
+
+    MyRectItem *topLevel = new MyRectItem;
+    topLevel->setGeometry(0, 0, 100, 100);
+    topLevel->setPos(-50, -50);
+    topLevel->brush = QBrush(QColor(Qt::black));
+    scene.addItem(topLevel);
+
+    MyRectItem *parent = new MyRectItem;
+    parent->topLevel = topLevel;
+    parent->setGeometry(0, 0, 100, 100);
+    parent->setPos(0, 0);
+    parent->brush = QBrush(QColor(Qt::magenta));
+    parent->setObjectName("parent");
+    scene.addItem(parent);
+
+    MyRectItem *child = new MyRectItem(parent);
+    child->setGeometry(0, 0, 80, 80);
+    child->setPos(10, 10);
+    child->setObjectName("child");
+    child->brush = QBrush(QColor(Qt::blue));
+
+    MyRectItem *child2 = new MyRectItem(parent);
+    child2->setGeometry(0, 0, 80, 80);
+    child2->setPos(15, 15);
+    child2->setObjectName("child2");
+    child2->brush = QBrush(QColor(Qt::green));
+
+    MyRectItem *child3 = new MyRectItem(parent);
+    child3->setGeometry(0, 0, 80, 80);
+    child3->setPos(20, 20);
+    child3->setObjectName("child3");
+    child3->brush = QBrush(QColor(Qt::gray));
+
+    QGraphicsView view(&scene);
+    view.show();
+    QTest::qWait(500);
+
+    //We move the parent
+    parent->move();
+    QTest::qWait(500);
+
+    //We check if all items moved
+    QCOMPARE(child->pos(), QPointF(10, 10));
+    QCOMPARE(child2->pos(), QPointF(15, 15));
+    QCOMPARE(child3->pos(), QPointF(20, 20));
+
+    QCOMPARE(child->sceneBoundingRect(), QRectF(-90, -90, 80, 80));
+    QCOMPARE(child2->sceneBoundingRect(), QRectF(-85, -85, 80, 80));
+    QCOMPARE(child3->sceneBoundingRect(), QRectF(-80, -80, 80, 80));
+
+    QCOMPARE(child->sceneTransform(), QTransform::fromTranslate(-90, -90));
+    QCOMPARE(child2->sceneTransform(), QTransform::fromTranslate(-85, -85));
+    QCOMPARE(child3->sceneTransform(), QTransform::fromTranslate(-80, -80));
+}
+
 QTEST_MAIN(tst_QGraphicsItem)
 #include "tst_qgraphicsitem.moc"