Upload VGImage data when drawing pixmaps that are being painted into.

When a painter is open on a pixmap's underlying QVolatileImage, it is
better to upload the VGImage content every time the pixmap is drawn
on the screen, in order to enable showing animations that are created
by continously rendering into the same pixmap and keeping the same
painter open.

Task-number: QT-4002
Reviewed-by: Jason Barron

1 files changed, 46 insertions, 0 deletions

diff --git a/tests/auto/qpixmap/tst_qpixmap.cpp b/tests/auto/qpixmap/tst_qpixmap.cpp
index 0b5c30be79..d103cb7423 100644
--- a/tests/auto/qpixmap/tst_qpixmap.cpp
+++ b/tests/auto/qpixmap/tst_qpixmap.cpp
@@ -194,6 +194,8 @@ private slots:
 #if defined(Q_OS_SYMBIAN) && !defined(QT_NO_OPENVG)
     void vgImageReadBack();
 #endif
+
+    void drawPixmapWhilePainterOpen();
 };
 
 static bool lenientCompare(const QPixmap &actual, const QPixmap &expected)
@@ -1881,5 +1883,49 @@ void tst_QPixmap::vgImageReadBack()
 }
 #endif // Symbian & OpenVG
 
+class PixmapWidget : public QWidget
+{
+public:
+    PixmapWidget(QPixmap &pixmap) : QWidget(0), m_pixmap(pixmap)
+    {
+        resize(pixmap.width(), pixmap.height());
+    }
+
+protected:
+    void paintEvent(QPaintEvent *)
+    {
+        QPainter p(this);
+        p.drawPixmap(0, 0, m_pixmap);
+    }
+
+private:
+    QPixmap &m_pixmap;
+};
+
+void tst_QPixmap::drawPixmapWhilePainterOpen()
+{
+    int size = 100;
+    QPixmap pix(size, size);
+    pix.fill(Qt::red);
+
+    PixmapWidget w(pix);
+    w.show();
+    QTest::qWaitForWindowShown(&w);
+    QTest::qWait(1000);
+
+    QPainter p(&pix);
+    p.fillRect(0, 0, size, size, Qt::blue);
+    w.update();
+    QTest::qWait(1000);
+
+    p.fillRect(0, 0, size, size, Qt::green);
+    w.update();
+    QTest::qWait(1000);
+
+    QPixmap actual = QPixmap::grabWindow(w.effectiveWinId(), 0, 0, size, size);
+
+    QVERIFY(lenientCompare(actual, pix));
+}
+
 QTEST_MAIN(tst_QPixmap)
 #include "tst_qpixmap.moc"