QPainter not restored correctly in Graphics View.

World transform and opacity was sometimes not restored correctly after
drawing items.

Auto test included.

Task-number: Discovered while working on QTBUG-12760

1 files changed, 43 insertions, 5 deletions

diff --git a/tests/auto/qgraphicsview/tst_qgraphicsview.cpp b/tests/auto/qgraphicsview/tst_qgraphicsview.cpp
index 7b5ac7a..af02c55 100644
--- a/tests/auto/qgraphicsview/tst_qgraphicsview.cpp
+++ b/tests/auto/qgraphicsview/tst_qgraphicsview.cpp
@@ -2492,25 +2492,31 @@ void tst_QGraphicsView::optimizationFlags_dontSavePainterState()
 void tst_QGraphicsView::optimizationFlags_dontSavePainterState2_data()
 {
     QTest::addColumn<bool>("savePainter");
-    QTest::newRow("With painter state protection") << true;
-    QTest::newRow("Without painter state protection") << false;
+    QTest::addColumn<bool>("indirectPainting");
+    QTest::newRow("With painter state protection, without indirect painting") << true << false;
+    QTest::newRow("Without painter state protection, without indirect painting") << false << false;
+    QTest::newRow("With painter state protectionm, with indirect painting") << true << true;
+    QTest::newRow("Without painter state protection, with indirect painting") << false << true;
 }
 
 void tst_QGraphicsView::optimizationFlags_dontSavePainterState2()
 {
     QFETCH(bool, savePainter);
+    QFETCH(bool, indirectPainting);
 
     class MyScene : public QGraphicsScene
     {
     public:
         void drawBackground(QPainter *p, const QRectF &)
-        { transformInDrawBackground = p->worldTransform(); }
+        { transformInDrawBackground = p->worldTransform(); opacityInDrawBackground = p->opacity(); }
 
         void drawForeground(QPainter *p, const QRectF &)
-        { transformInDrawForeground = p->worldTransform(); }
+        { transformInDrawForeground = p->worldTransform(); opacityInDrawForeground = p->opacity(); }
 
         QTransform transformInDrawBackground;
         QTransform transformInDrawForeground;
+        qreal opacityInDrawBackground;
+        qreal opacityInDrawForeground;
     };
 
     MyScene scene;
@@ -2518,9 +2524,13 @@ void tst_QGraphicsView::optimizationFlags_dontSavePainterState2()
     scene.addRect(0, 0, 20, 20)->setTransform(QTransform::fromScale(2, 2));
     scene.addRect(50, 50, 20, 20)->setTransform(QTransform::fromTranslate(200, 200));
 
+    foreach (QGraphicsItem *item, scene.items())
+        item->setOpacity(0.6);
+
     CustomView view(&scene);
     if (!savePainter)
         view.setOptimizationFlag(QGraphicsView::DontSavePainterState);
+    view.setOptimizationFlag(QGraphicsView::IndirectPainting, indirectPainting);
     view.rotate(45);
     view.scale(1.5, 1.5);
     view.show();
@@ -2534,10 +2544,38 @@ void tst_QGraphicsView::optimizationFlags_dontSavePainterState2()
     QVERIFY(view.painted);
 
     // Make sure the painter's world transform is preserved after drawItems.
-    const QTransform expectedTransform = view.viewportTransform();
+    QTransform expectedTransform = view.viewportTransform();
     QVERIFY(!expectedTransform.isIdentity());
     QCOMPARE(scene.transformInDrawForeground, expectedTransform);
     QCOMPARE(scene.transformInDrawBackground, expectedTransform);
+
+    qreal expectedOpacity = 1.0;
+    QCOMPARE(scene.opacityInDrawBackground, expectedOpacity);
+    QCOMPARE(scene.opacityInDrawForeground, expectedOpacity);
+
+    // Trigger more painting, this time from QGraphicsScene::render.
+    QImage image(scene.sceneRect().size().toSize(), QImage::Format_RGB32);
+    QPainter painter(&image);
+    scene.render(&painter);
+    painter.end();
+
+    expectedTransform = QTransform();
+    QCOMPARE(scene.transformInDrawForeground, expectedTransform);
+    QCOMPARE(scene.transformInDrawBackground, expectedTransform);
+    QCOMPARE(scene.opacityInDrawBackground, expectedOpacity);
+    QCOMPARE(scene.opacityInDrawForeground, expectedOpacity);
+
+    // Trigger more painting with another opacity on the painter.
+    painter.begin(&image);
+    painter.setOpacity(0.4);
+    expectedOpacity = 0.4;
+    scene.render(&painter);
+    painter.end();
+
+    QCOMPARE(scene.transformInDrawForeground, expectedTransform);
+    QCOMPARE(scene.transformInDrawBackground, expectedTransform);
+    QCOMPARE(scene.opacityInDrawBackground, expectedOpacity);
+    QCOMPARE(scene.opacityInDrawForeground, expectedOpacity);
 }
 
 class LodItem : public QGraphicsRectItem