Improve direct2d backing store implementation

Add a per-window swap chain to a QPlatformWindow subclass instead of tying
it to the backing store. This is needed to support native widgets (as
opposed to alien widgets).

Change the backing store to draw to an intermediate pixmap and flush to
the requested window by using the per-window swap chain. This also opens
the door for faster window presentation later on by using the swap chain
more intelligently.

Also add a changelog entry for the direct2d plugin, which was omitted
earlier.

[ChangeLog][QtGui][Windows]
Introduce experimental direct2d platform plugin for Windows. This plugin
shares most code with the current windows plugin, but substitutes a
direct2d-based paint engine for window backing stores and pixmaps.

Change-Id: I5f54e7e4c1fb15b1639bd26b712fb40ac141e4ac
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>

1 files changed, 74 insertions, 0 deletions

diff --git a/src/plugins/platforms/direct2d/qwindowsdirect2dwindow.h b/src/plugins/platforms/direct2d/qwindowsdirect2dwindow.h
new file mode 100644
index 0000000000..7996904639
--- /dev/null
+++ b/src/plugins/platforms/direct2d/qwindowsdirect2dwindow.h
@@ -0,0 +1,74 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QWINDOWSDIRECT2DWINDOW_H
+#define QWINDOWSDIRECT2DWINDOW_H
+
+#include "qwindowswindow.h"
+#include "qwindowsdirect2dbitmap.h"
+
+#include <dxgi1_2.h>
+#include <wrl.h>
+
+QT_BEGIN_NAMESPACE
+
+class QWindowsDirect2DWindow : public QWindowsWindow
+{
+public:
+    QWindowsDirect2DWindow(QWindow *window, const QWindowsWindowData &data);
+    ~QWindowsDirect2DWindow();
+
+    void flush(QWindowsDirect2DBitmap *bitmap, const QRegion &region, const QPoint &offset);
+
+private:
+    void resizeSwapChain(const QSize &size);
+    void setupBitmap();
+
+private:
+    Microsoft::WRL::ComPtr<IDXGISwapChain1> m_swapChain;
+    Microsoft::WRL::ComPtr<ID2D1DeviceContext> m_deviceContext;
+    QScopedPointer<QWindowsDirect2DBitmap> m_bitmap;
+    bool m_needsFullFlush;
+};
+
+QT_END_NAMESPACE
+
+#endif // QWINDOWSDIRECT2DWINDOW_H