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#include "qplatformbackingstore.h"
#include <qwindow.h>
#include <qpixmap.h>
#include <private/qwindow_p.h>

QT_BEGIN_NAMESPACE

class QPlatformBackingStorePrivate
{
public:
    QPlatformBackingStorePrivate(QWindow *w)
        : window(w)
    {
    }

    QWindow *window;
    QSize size;
};

/*!
    \class QPlatformBackingStore
    \since 5.0
    \internal
    \preliminary
    \ingroup qpa

    \brief The QPlatformBackingStore class provides the drawing area for top-level
    windows.
*/

/*!
    \fn void QPlatformBackingStore::flush(QWindow *window, const QRegion &region,
                                  const QPoint &offset)

    Flushes the given \a region from the specified \a window onto the
    screen.

    Note that the \a offset parameter is currently unused.
*/

/*!
    \fn QPaintDevice* QPlatformBackingStore::paintDevice()

    Implement this function to return the appropriate paint device.
*/

/*!
    Constructs an empty surface for the given top-level \a window.
*/
QPlatformBackingStore::QPlatformBackingStore(QWindow *window)
    : d_ptr(new QPlatformBackingStorePrivate(window))
{
}

/*!
    Destroys this surface.
*/
QPlatformBackingStore::~QPlatformBackingStore()
{
    delete d_ptr;
}

/*!
    Returns a pointer to the top-level window associated with this
    surface.
*/
QWindow* QPlatformBackingStore::window() const
{
    return d_ptr->window;
}

/*!
    This function is called before painting onto the surface begins,
    with the \a region in which the painting will occur.

    \sa endPaint(), paintDevice()
*/

void QPlatformBackingStore::beginPaint(const QRegion &)
{
}

/*!
    This function is called after painting onto the surface has ended.

    \sa beginPaint(), paintDevice()
*/

void QPlatformBackingStore::endPaint()
{
}

/*!
    Scrolls the given \a area \a dx pixels to the right and \a dy
    downward; both \a dx and \a dy may be negative.

    Returns true if the area was scrolled successfully; false otherwise.
*/
bool QPlatformBackingStore::scroll(const QRegion &area, int dx, int dy)
{
    Q_UNUSED(area);
    Q_UNUSED(dx);
    Q_UNUSED(dy);

    return false;
}

QT_END_NAMESPACE
