QRuntimeGraphicsSystem

QRuntimeGraphicsSystem is a proxy graphics system which
can dynamically switch underlying graphics system on runtime.
For example, switch from hardware accelerated graphics system
to raster graphics system on low GPU memory situation. This
feature is currently supported on Symbian platform.

Task-number: QT-3276
Reviewed-by: Jason Barron

1 files changed, 197 insertions, 0 deletions

diff --git a/src/gui/painting/qgraphicssystem_runtime_p.h b/src/gui/painting/qgraphicssystem_runtime_p.h
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+++ b/src/gui/painting/qgraphicssystem_runtime_p.h
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+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** 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, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QGRAPHICSSYSTEM_RUNTIME_P_H
+#define QGRAPHICSSYSTEM_RUNTIME_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists for the convenience
+// of other Qt classes.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include "qgraphicssystem_p.h"
+
+#include <private/qpixmapdata_p.h>
+
+QT_BEGIN_NAMESPACE
+
+class QRuntimeGraphicsSystem;
+
+class QRuntimePixmapData : public QPixmapData {
+public:
+    QRuntimePixmapData(const QRuntimeGraphicsSystem *gs, PixelType type);
+    ~QRuntimePixmapData();
+
+    virtual QPixmapData *createCompatiblePixmapData() const;
+    virtual void resize(int width, int height);
+    virtual void fromImage(const QImage &image,
+                           Qt::ImageConversionFlags flags);
+
+    virtual bool fromFile(const QString &filename, const char *format,
+                          Qt::ImageConversionFlags flags);
+    virtual bool fromData(const uchar *buffer, uint len, const char *format,
+                          Qt::ImageConversionFlags flags);
+
+    virtual void copy(const QPixmapData *data, const QRect &rect);
+    virtual bool scroll(int dx, int dy, const QRect &rect);
+
+    virtual int metric(QPaintDevice::PaintDeviceMetric metric) const;
+    virtual void fill(const QColor &color);
+    virtual QBitmap mask() const;
+    virtual void setMask(const QBitmap &mask);
+    virtual bool hasAlphaChannel() const;
+    virtual QPixmap transformed(const QTransform &matrix,
+                                Qt::TransformationMode mode) const;
+    virtual void setAlphaChannel(const QPixmap &alphaChannel);
+    virtual QPixmap alphaChannel() const;
+    virtual QImage toImage() const;
+    virtual QPaintEngine *paintEngine() const;
+
+    virtual QImage *buffer();
+
+    void readBackInfo();
+
+    QPixmapData *m_data;
+
+#if defined(Q_OS_SYMBIAN)
+    void* toNativeType(NativeType type);
+    void fromNativeType(void* pixmap, NativeType type);
+#endif
+
+    virtual QPixmapData *runtimeData() const;
+
+    virtual uint memoryUsage() const;
+
+private:
+    const QRuntimeGraphicsSystem *m_graphicsSystem;
+
+};
+
+class QRuntimeWindowSurface : public QWindowSurface {
+public:
+    QRuntimeWindowSurface(const QRuntimeGraphicsSystem *gs, QWidget *window);
+    ~QRuntimeWindowSurface();
+
+    virtual QPaintDevice *paintDevice();
+    virtual void flush(QWidget *widget, const QRegion &region,
+                       const QPoint &offset);
+    virtual void setGeometry(const QRect &rect);
+
+    virtual bool scroll(const QRegion &area, int dx, int dy);
+
+    virtual void beginPaint(const QRegion &);
+    virtual void endPaint(const QRegion &);
+
+    virtual QImage* buffer(const QWidget *widget);
+    virtual QPixmap grabWidget(const QWidget *widget, const QRect& rectangle = QRect()) const;
+
+    virtual QPoint offset(const QWidget *widget) const;
+
+    virtual uint memoryUsage() const;
+
+    QWindowSurface *m_windowSurface;
+    QWindowSurface *m_pendingWindowSurface;
+
+private:
+    const QRuntimeGraphicsSystem *m_graphicsSystem;
+};
+
+class QRuntimeGraphicsSystem : public QGraphicsSystem
+{
+public:
+
+    enum WindowSurfaceDestroyPolicy
+    {
+        DestroyImmediately,
+        DestroyAfterFirstFlush
+    };
+
+public:
+    QRuntimeGraphicsSystem();
+
+    QPixmapData *createPixmapData(QPixmapData::PixelType type) const;
+    QWindowSurface *createWindowSurface(QWidget *widget) const;
+
+    void removePixmapData(QRuntimePixmapData *pixmapData) const;
+    void removeWindowSurface(QRuntimeWindowSurface *windowSurface) const;
+
+    void setGraphicsSystem(const QString &name, uint memoryUsageLimit);
+    void setGraphicsSystem(const QString &name);
+    QString graphicsSystemName() const { return m_graphicsSystemName; }
+
+    void setWindowSurfaceDestroyPolicy(WindowSurfaceDestroyPolicy policy)
+    {
+        m_windowSurfaceDestroyPolicy = policy;
+    }
+
+    int windowSurfaceDestroyPolicy() const { return m_windowSurfaceDestroyPolicy; }
+
+    int memoryUsage() const { return m_memoryUsage; }
+
+private:
+
+    void increaseMemoryUsage(uint amount) const;
+    void decreaseMemoryUsage(uint amount, bool persistent = false) const;
+
+private:
+    mutable uint m_memoryUsage;
+    int m_windowSurfaceDestroyPolicy;
+    QGraphicsSystem *m_graphicsSystem;
+    mutable QList<QRuntimePixmapData *> m_pixmapDatas;
+    mutable QList<QRuntimeWindowSurface *> m_windowSurfaces;
+    QString m_graphicsSystemName;
+
+    uint m_graphicsSystemChangeMemoryLimit;
+    QString m_pendingGraphicsSystemName;
+
+    friend class QRuntimePixmapData;
+    friend class QRuntimeWindowSurface;
+};
+
+QT_END_NAMESPACE
+
+#endif