diff -r 000000000000 -r 4f2f89ce4247 WebKit2/UIProcess/qt/ChunkedUpdateDrawingAreaProxyQt.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WebKit2/UIProcess/qt/ChunkedUpdateDrawingAreaProxyQt.cpp	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2010 Apple Inc. All rights reserved.
+ * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ * THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "ChunkedUpdateDrawingAreaProxy.h"
+
+#include "DrawingAreaMessageKinds.h"
+#include "DrawingAreaProxyMessageKinds.h"
+#include "UpdateChunk.h"
+#include "WKAPICast.h"
+#include "WebPageProxy.h"
+#include "qgraphicswkview.h"
+#include <QPainter>
+
+using namespace WebCore;
+
+namespace WebKit {
+
+WebPageProxy* ChunkedUpdateDrawingAreaProxy::page()
+{
+    return toWK(m_webView->page()->pageRef());
+}
+
+void ChunkedUpdateDrawingAreaProxy::ensureBackingStore()
+{
+    if (!m_backingStoreImage.isNull())
+        return;
+
+    m_backingStoreImage = QImage(m_viewSize.width(), m_viewSize.height(), QImage::Format_RGB32);
+}
+
+void ChunkedUpdateDrawingAreaProxy::invalidateBackingStore()
+{
+    m_backingStoreImage = QImage();
+}
+
+void ChunkedUpdateDrawingAreaProxy::platformPaint(const IntRect& rect, QPainter* painter)
+{
+    if (m_backingStoreImage.isNull())
+        return;
+
+    painter->drawImage(QPoint(0, 0), m_backingStoreImage);
+}
+
+void ChunkedUpdateDrawingAreaProxy::drawUpdateChunkIntoBackingStore(UpdateChunk* updateChunk)
+{
+    ensureBackingStore();
+
+    QImage image(updateChunk->createImage());
+    const IntRect& updateChunkRect = updateChunk->rect();
+
+    QPainter painter(&m_backingStoreImage);
+    painter.drawImage(updateChunkRect.topLeft(), image);
+
+    m_webView->update(QRect(updateChunkRect));
+}
+
+} // namespace WebKit