source: trunk/src/gui/image/qpixmap.cpp@ 147

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#include <qglobal.h>

#include "qpixmap.h"
#include "qpixmapdata_p.h"

#include "qbitmap.h"
#include "qcolormap.h"
#include "qimage.h"
#include "qwidget.h"
#include "qpainter.h"
#include "qdatastream.h"
#include "qbuffer.h"
#include "qapplication.h"
#include <private/qapplication_p.h>
#include <private/qgraphicssystem_p.h>
#include <private/qwidget_p.h>
#include "qevent.h"
#include "qfile.h"
#include "qfileinfo.h"
#include "qpixmapcache.h"
#include "qdatetime.h"
#include "qimagereader.h"
#include "qimagewriter.h"
#include "qpaintengine.h"
#include "qthread.h"

#ifdef Q_WS_MAC
# include "private/qt_mac_p.h"
# include "private/qpixmap_mac_p.h"
#endif

#if defined(Q_WS_X11)
# include "qx11info_x11.h"
# include <private/qt_x11_p.h>
# include <private/qpixmap_x11_p.h>
#endif

#include "qpixmap_raster_p.h"

QT_BEGIN_NAMESPACE

// ### Qt 5: remove
typedef void (*_qt_pixmap_cleanup_hook)(int);
Q_GUI_EXPORT _qt_pixmap_cleanup_hook qt_pixmap_cleanup_hook = 0;

// ### Qt 5: rename
typedef void (*_qt_pixmap_cleanup_hook_64)(qint64);
Q_GUI_EXPORT _qt_pixmap_cleanup_hook_64 qt_pixmap_cleanup_hook_64 = 0;

// ### Qt 5: remove
Q_GUI_EXPORT qint64 qt_pixmap_id(const QPixmap &pixmap)
{
    return pixmap.cacheKey();
}

static bool qt_pixmap_thread_test()
{
    if (!qApp) {
        qFatal("QPixmap: Must construct a QApplication before a QPaintDevice");
        return false;
    }
#ifndef Q_WS_WIN
    if (qApp->thread() != QThread::currentThread()) {
        qWarning("QPixmap: It is not safe to use pixmaps outside the GUI thread");
        return false;
    }
#endif
    return true;
}

void QPixmap::init(int w, int h, Type type)
{
    init(w, h, int(type));
}

void QPixmap::init(int w, int h, int type)
{
    QGraphicsSystem* gs = QApplicationPrivate::graphicsSystem();
    if (gs)
        data = gs->createPixmapData(static_cast<QPixmapData::PixelType>(type));
    else
        data = QGraphicsSystem::createDefaultPixmapData(static_cast<QPixmapData::PixelType>(type));

    data->resize(w, h);
    data->ref.ref();
}

/*!
    \enum QPixmap::ColorMode

    \compat

    This enum type defines the color modes that exist for converting
    QImage objects to QPixmap.  It is provided here for compatibility
    with earlier versions of Qt.

    Use Qt::ImageConversionFlags instead.

    \value Auto  Select \c Color or \c Mono on a case-by-case basis.
    \value Color Always create colored pixmaps.
    \value Mono  Always create bitmaps.
*/

/*!
    Constructs a null pixmap.

    \sa isNull()
*/

QPixmap::QPixmap()
    : QPaintDevice()
{
    (void) qt_pixmap_thread_test();
    init(0, 0, QPixmapData::PixmapType);
}

/*!
    \fn QPixmap::QPixmap(int width, int height)

    Constructs a pixmap with the given \a width and \a height. If
    either \a width or \a height is zero, a null pixmap is
    constructed.

    \warning This will create a QPixmap with uninitialized data. Call
    fill() to fill the pixmap with an appropriate color before drawing
    onto it with QPainter.

    \sa isNull()
*/

QPixmap::QPixmap(int w, int h)
    : QPaintDevice()
{
    if (!qt_pixmap_thread_test())
        init(0, 0, QPixmapData::PixmapType);
    else
        init(w, h, QPixmapData::PixmapType);
}

/*!
    \overload

    Constructs a pixmap of the given \a size.

    \warning This will create a QPixmap with uninitialized data. Call
    fill() to fill the pixmap with an appropriate color before drawing
    onto it with QPainter.
*/

QPixmap::QPixmap(const QSize &size)
    : QPaintDevice()
{
    if (!qt_pixmap_thread_test())
        init(0, 0, QPixmapData::PixmapType);
    else
        init(size.width(), size.height(), QPixmapData::PixmapType);
}

/*!
  \internal
*/
QPixmap::QPixmap(const QSize &s, Type type)
{
    if (!qt_pixmap_thread_test())
        init(0, 0, type);
    else
        init(s.width(), s.height(), type);
}

/*!
  \internal
*/
QPixmap::QPixmap(const QSize &s, int type)
{
    if (!qt_pixmap_thread_test())
        init(0, 0, static_cast<QPixmapData::PixelType>(type));
    else
        init(s.width(), s.height(), static_cast<QPixmapData::PixelType>(type));
}

/*!
    \internal
*/
QPixmap::QPixmap(QPixmapData *d)
    : QPaintDevice(), data(d)
{
    data->ref.ref();
}

/*!
    Constructs a pixmap from the file with the given \a fileName. If the
    file does not exist or is of an unknown format, the pixmap becomes a
    null pixmap.

    The loader attempts to read the pixmap using the specified \a
    format. If the \a format is not specified (which is the default),
    the loader probes the file for a header to guess the file format.

    The file name can either refer to an actual file on disk or to
    one of the application's embedded resources. See the
    \l{resources.html}{Resource System} overview for details on how
    to embed images and other resource files in the application's
    executable.

    If the image needs to be modified to fit in a lower-resolution
    result (e.g. converting from 32-bit to 8-bit), use the \a
    flags to control the conversion.

    The \a fileName, \a format and \a flags parameters are
    passed on to load(). This means that the data in \a fileName is
    not compiled into the binary. If \a fileName contains a relative
    path (e.g. the filename only) the relevant file must be found
    relative to the runtime working directory.

    \sa {QPixmap#Reading and Writing Image Files}{Reading and Writing
    Image Files}
*/

QPixmap::QPixmap(const QString& fileName, const char *format, Qt::ImageConversionFlags flags)
    : QPaintDevice()
{
    init(0, 0, QPixmapData::PixmapType);
    if (!qt_pixmap_thread_test())
        return;

    load(fileName, format, flags);
}

/*!
    Constructs a pixmap that is a copy of the given \a pixmap.

    \sa copy()
*/

QPixmap::QPixmap(const QPixmap &pixmap)
    : QPaintDevice()
{
    if (!qt_pixmap_thread_test()) {
        init(0, 0, QPixmapData::PixmapType);
        return;
    }
    if (pixmap.paintingActive()) {                // make a deep copy
        data = 0;
        operator=(pixmap.copy());
    } else {
        data = pixmap.data;
        data->ref.ref();
    }
}

/*!
    Constructs a pixmap from the given \a xpm data, which must be a
    valid XPM image.

    Errors are silently ignored.

    Note that it's possible to squeeze the XPM variable a little bit
    by using an unusual declaration:

    \snippet doc/src/snippets/code/src_gui_image_qpixmap.cpp 0

    The extra \c const makes the entire definition read-only, which is
    slightly more efficient (for example, when the code is in a shared
    library) and ROMable when the application is to be stored in ROM.
*/
#ifndef QT_NO_IMAGEFORMAT_XPM
QPixmap::QPixmap(const char * const xpm[])
    : QPaintDevice()
{
    init(0, 0, QPixmapData::PixmapType);
    if (!xpm)
        return;

    QImage image(xpm);
    if (!image.isNull()) {
        if (data->pixelType() == QPixmapData::BitmapType)
            *this = QBitmap::fromImage(image);
        else
            *this = fromImage(image);
    }
}
#endif


/*!
    Destroys the pixmap.
*/

QPixmap::~QPixmap()
{
    deref();
}

/*!
  \internal
*/
int QPixmap::devType() const
{
    return QInternal::Pixmap;
}

/*!
    \fn QPixmap QPixmap::copy(int x, int y, int width, int height) const
    \overload

    Returns a deep copy of the subset of the pixmap that is specified
    by the rectangle QRect( \a x, \a y, \a width, \a height).
*/

/*!
    \fn QPixmap QPixmap::copy(const QRect &rectangle) const

    Returns a deep copy of the subset of the pixmap that is specified
    by the given \a rectangle. For more information on deep copies,
    see the \l {Implicit Data Sharing} documentation.

    If the given \a rectangle is empty, the whole image is copied.

    \sa operator=(), QPixmap(), {QPixmap#Pixmap
    Transformations}{Pixmap Transformations}
*/
QPixmap QPixmap::copy(const QRect &rect) const
{
    if (isNull())
        return QPixmap();

    const QRect r = rect.isEmpty() ? QRect(0, 0, width(), height()) : rect;

    QPixmapData *d;
    QGraphicsSystem* gs = QApplicationPrivate::graphicsSystem();
    if (gs)
        d = gs->createPixmapData(data->pixelType());
    else
        d = QGraphicsSystem::createDefaultPixmapData(data->pixelType());

    d->copy(data, r);
    return QPixmap(d);
}

/*!
    Assigns the given \a pixmap to this pixmap and returns a reference
    to this pixmap.

    \sa copy(), QPixmap()
*/

QPixmap &QPixmap::operator=(const QPixmap &pixmap)
{
    if (paintingActive()) {
        qWarning("QPixmap::operator=: Cannot assign to pixmap during painting");
        return *this;
    }
    if (pixmap.paintingActive()) {                // make a deep copy
        *this = pixmap.copy();
    } else {
        pixmap.data->ref.ref();                                // avoid 'x = x'
        deref();
        data = pixmap.data;
    }
    return *this;
}

/*!
   Returns the pixmap as a QVariant.
*/
QPixmap::operator QVariant() const
{
    return QVariant(QVariant::Pixmap, this);
}

/*!
    \fn bool QPixmap::operator!() const

    Returns true if this is a null pixmap; otherwise returns false.

    \sa isNull()
*/

/*!
    \fn QPixmap::operator QImage() const

    Returns the pixmap as a QImage.

    Use the toImage() function instead.
*/

/*!
    Converts the pixmap to a QImage. Returns a null image if the
    conversion fails.

    If the pixmap has 1-bit depth, the returned image will also be 1
    bit deep. If the pixmap has 2- to 8-bit depth, the returned image
    has 8-bit depth. If the pixmap has greater than 8-bit depth, the
    returned image has 32-bit depth.

    Note that for the moment, alpha masks on monochrome images are
    ignored.

    \sa fromImage(), {QImage#Image Formats}{Image Formats}
*/
QImage QPixmap::toImage() const
{
    if (isNull())
        return QImage();

    return data->toImage();
}

/*!
    \fn QMatrix QPixmap::trueMatrix(const QTransform &matrix, int width, int height)

    Returns the actual matrix used for transforming a pixmap with the
    given \a width, \a height and \a matrix.

    When transforming a pixmap using the transformed() function, the
    transformation matrix is internally adjusted to compensate for
    unwanted translation, i.e. transformed() returns the smallest
    pixmap containing all transformed points of the original
    pixmap. This function returns the modified matrix, which maps
    points correctly from the original pixmap into the new pixmap.

    \sa transformed(), {QPixmap#Pixmap Transformations}{Pixmap
    Transformations}
*/
QTransform QPixmap::trueMatrix(const QTransform &m, int w, int h)
{
    return QImage::trueMatrix(m, w, h);
}

/*!
  \overload

  This convenience function loads the matrix \a m into a
  QTransform and calls the overloaded function with the
  QTransform and the width \a w and the height \a h.
 */
QMatrix QPixmap::trueMatrix(const QMatrix &m, int w, int h)
{
    return trueMatrix(QTransform(m), w, h).toAffine();
}


/*!
    \fn bool QPixmap::isQBitmap() const

    Returns true if this is a QBitmap; otherwise returns false.
*/

bool QPixmap::isQBitmap() const
{
    return data->type == QPixmapData::BitmapType;
}

/*!
    \fn bool QPixmap::isNull() const

    Returns true if this is a null pixmap; otherwise returns false.

    A null pixmap has zero width, zero height and no contents. You
    cannot draw in a null pixmap.
*/
bool QPixmap::isNull() const
{
    return data->width() == 0;
}

/*!
    \fn int QPixmap::width() const

    Returns the width of the pixmap.

    \sa size(), {QPixmap#Pixmap Information}{Pixmap Information}
*/
int QPixmap::width() const
{
    return data->width();
}

/*!
    \fn int QPixmap::height() const

    Returns the height of the pixmap.

    \sa size(), {QPixmap#Pixmap Information}{Pixmap Information}
*/
int QPixmap::height() const
{
    return data->height();
}

/*!
    \fn QSize QPixmap::size() const

    Returns the size of the pixmap.

    \sa width(), height(), {QPixmap#Pixmap Information}{Pixmap
    Information}
*/
QSize QPixmap::size() const
{
    return QSize(data->width(), data->height());
}

/*!
    \fn QRect QPixmap::rect() const

    Returns the pixmap's enclosing rectangle.

    \sa {QPixmap#Pixmap Information}{Pixmap Information}
*/
QRect QPixmap::rect() const
{
    return QRect(0, 0, data->width(), data->height());
}

/*!
    \fn int QPixmap::depth() const

    Returns the depth of the pixmap.

    The pixmap depth is also called bits per pixel (bpp) or bit planes
    of a pixmap. A null pixmap has depth 0.

    \sa defaultDepth(), {QPixmap#Pixmap Information}{Pixmap
    Information}
*/
int QPixmap::depth() const
{
    return data->depth();
}

/*!
    \fn void QPixmap::resize(const QSize &size)
    \overload
    \compat

    Use QPixmap::copy() instead to get the pixmap with the new size.

    \oldcode
        pixmap.resize(size);
    \newcode
        pixmap = pixmap.copy(QRect(QPoint(0, 0), size));
    \endcode
*/
#ifdef QT3_SUPPORT
void QPixmap::resize_helper(const QSize &s)
{
    int w = s.width();
    int h = s.height();
    if (w < 1 || h < 1) {
        *this = QPixmap();
        return;
    }

    if (size() == s)
        return;

    // Create new pixmap
    QPixmap pm(QSize(w, h), data->type);
    bool uninit = false;
#if defined(Q_WS_X11)
    QX11PixmapData *x11Data = data->classId() == QPixmapData::X11Class ? static_cast<QX11PixmapData*>(data) : 0;
    if (x11Data) {
        pm.x11SetScreen(x11Data->xinfo.screen());
        uninit = x11Data->uninit;
    }
#elif defined(Q_WS_MAC)
    QMacPixmapData *macData = data->classId() == QPixmapData::MacClass ? static_cast<QMacPixmapData*>(data) : 0;
    if (macData)
        uninit = macData->uninit;
#endif
    if (!uninit && !isNull()) {
        // Copy old pixmap
        if (hasAlphaChannel())
            pm.fill(Qt::transparent);
        QPainter p(&pm);
        p.drawPixmap(0, 0, *this, 0, 0, qMin(width(), w), qMin(height(), h));
    }

#if defined(Q_WS_MAC)
#ifndef QT_MAC_NO_QUICKDRAW
    if(macData && macData->qd_alpha)
        macData->macQDUpdateAlpha();
#endif
#elif defined(Q_WS_X11)
    if (x11Data && x11Data->x11_mask) {
        QX11PixmapData *pmData = static_cast<QX11PixmapData*>(pm.data);
        pmData->x11_mask = (Qt::HANDLE)XCreatePixmap(X11->display,
                                                     RootWindow(x11Data->xinfo.display(),
                                                                x11Data->xinfo.screen()),
                                                      w, h, 1);
        GC gc = XCreateGC(X11->display, pmData->x11_mask, 0, 0);
        XCopyArea(X11->display, x11Data->x11_mask, pmData->x11_mask, gc, 0, 0, qMin(width(), w), qMin(height(), h), 0, 0);
        XFreeGC(X11->display, gc);
    }
#endif
    *this = pm;
}
#endif

/*!
    \fn void QPixmap::resize(int width, int height)
    \compat

    Use QPixmap::copy() instead to get the pixmap with the new size.

    \oldcode
        pixmap.resize(10, 20);
    \newcode
        pixmap = pixmap.copy(0, 0, 10, 20);
    \endcode
*/

/*!
    \fn bool QPixmap::selfMask() const
    \compat

    Returns whether the pixmap is its own mask or not.

    This function is no longer relevant since the concept of self
    masking doesn't exists anymore.
*/

/*!
    Sets a mask bitmap.

    This function merges the \a mask with the pixmap's alpha channel. A pixel
    value of 1 on the mask means the pixmap's pixel is unchanged; a value of 0
    means the pixel is transparent. The mask must have the same size as this
    pixmap.

    Setting a null mask resets the mask, leaving the previously transparent
    pixels black. The effect of this function is undefined when the pixmap is
    being painted on.

    This is potentially an expensive operation.

    \sa mask(), {QPixmap#Pixmap Transformations}{Pixmap Transformations},
    QBitmap
*/
void QPixmap::setMask(const QBitmap &mask)
{
    if (paintingActive()) {
        qWarning("QPixmap::setMask: Cannot set mask while pixmap is being painted on");
        return;
    }

    if (!mask.isNull() && mask.size() != size()) {
        qWarning("QPixmap::setMask() mask size differs from pixmap size");
        return;
    }

    if (static_cast<const QPixmap &>(mask).data == data) // trying to selfmask
       return;

    detach();
    data->setMask(mask);
}

#ifndef QT_NO_IMAGE_HEURISTIC_MASK
/*!
    Creates and returns a heuristic mask for this pixmap.

    The function works by selecting a color from one of the corners
    and then chipping away pixels of that color, starting at all the
    edges.  If \a clipTight is true (the default) the mask is just
    large enough to cover the pixels; otherwise, the mask is larger
    than the data pixels.

    The mask may not be perfect but it should be reasonable, so you
    can do things such as the following:

    \snippet doc/src/snippets/code/src_gui_image_qpixmap.cpp 1

    This function is slow because it involves converting to/from a
    QImage, and non-trivial computations.

    \sa QImage::createHeuristicMask(), createMaskFromColor()
*/
QBitmap QPixmap::createHeuristicMask(bool clipTight) const
{
    QBitmap m = QBitmap::fromImage(toImage().createHeuristicMask(clipTight));
    return m;
}
#endif

/*!
    Creates and returns a mask for this pixmap based on the given \a
    maskColor. If the \a mode is Qt::MaskInColor, all pixels matching the
    maskColor will be opaque. If \a mode is Qt::MaskOutColor, all pixels
    matching the maskColor will be transparent.

    This function is slow because it involves converting to/from a
    QImage.

    \sa createHeuristicMask(), QImage::createMaskFromColor()
*/
QBitmap QPixmap::createMaskFromColor(const QColor &maskColor, Qt::MaskMode mode) const
{
    QImage image = toImage().convertToFormat(QImage::Format_ARGB32);
    return QBitmap::fromImage(image.createMaskFromColor(maskColor.rgba(), mode));
}

/*! \overload

    Creates and returns a mask for this pixmap based on the given \a
    maskColor. Same as calling createMaskFromColor(maskColor,
    Qt::MaskInColor)

    \sa createHeuristicMask(), QImage::createMaskFromColor()
*/
QBitmap QPixmap::createMaskFromColor(const QColor &maskColor) const
{
    return createMaskFromColor(maskColor, Qt::MaskInColor);
}

/*!
    Loads a pixmap from the file with the given \a fileName. Returns
    true if the pixmap was successfully loaded; otherwise returns
    false.

    The loader attempts to read the pixmap using the specified \a
    format. If the \a format is not specified (which is the default),
    the loader probes the file for a header to guess the file format.

    The file name can either refer to an actual file on disk or to one
    of the application's embedded resources. See the
    \l{resources.html}{Resource System} overview for details on how to
    embed pixmaps and other resource files in the application's
    executable.

    If the data needs to be modified to fit in a lower-resolution
    result (e.g. converting from 32-bit to 8-bit), use the \a flags to
    control the conversion.

    Note that QPixmaps are automatically added to the QPixmapCache
    when loaded from a file; the key used is internal and can not
    be acquired.

    \sa loadFromData(), {QPixmap#Reading and Writing Image
    Files}{Reading and Writing Image Files}
*/

bool QPixmap::load(const QString &fileName, const char *format, Qt::ImageConversionFlags flags)
{
    if (fileName.isEmpty())
        return false;

    QFileInfo info(fileName);
    QString key = QLatin1String("qt_pixmap_") + info.absoluteFilePath() + QLatin1Char('_') + QString::number(info.lastModified().toTime_t()) + QLatin1Char('_') +
                  QString::number(info.size()) + QLatin1Char('_') + QString::number(data->pixelType());

    if (QPixmapCache::find(key, *this))
        return true;

    QImage image = QImageReader(fileName, format).read();
    if (image.isNull())
        return false;
    QPixmap pm;
    if (data->pixelType() == QPixmapData::BitmapType)
        pm = QBitmap::fromImage(image, flags);
    else
        pm = fromImage(image, flags);
    if (!pm.isNull()) {
        *this = pm;
        QPixmapCache::insert(key, *this);
        return true;
    }
    return false;
}

/*!
    \fn bool QPixmap::loadFromData(const uchar *data, uint len, const char *format, Qt::ImageConversionFlags flags)

    Loads a pixmap from the \a len first bytes of the given binary \a
    data.  Returns true if the pixmap was loaded successfully;
    otherwise returns false.

    The loader attempts to read the pixmap using the specified \a
    format. If the \a format is not specified (which is the default),
    the loader probes the file for a header to guess the file format.

    If the data needs to be modified to fit in a lower-resolution
    result (e.g. converting from 32-bit to 8-bit), use the \a flags to
    control the conversion.

    \sa load(), {QPixmap#Reading and Writing Image Files}{Reading and
    Writing Image Files}
*/

bool QPixmap::loadFromData(const uchar *buf, uint len, const char *format, Qt::ImageConversionFlags flags)
{
    QByteArray a = QByteArray::fromRawData(reinterpret_cast<const char *>(buf), len);
    QBuffer b(&a);
    b.open(QIODevice::ReadOnly);

    QImage image = QImageReader(&b, format).read();
    QPixmap pm;
    if (data->pixelType() == QPixmapData::BitmapType)
        pm = QBitmap::fromImage(image, flags);
    else
        pm = fromImage(image, flags);
    if (!pm.isNull()) {
        *this = pm;
        return true;
    }
    return false;
}

/*!
    \fn bool QPixmap::loadFromData(const QByteArray &data, const char *format, Qt::ImageConversionFlags flags)

    \overload

    Loads a pixmap from the binary \a data using the specified \a
    format and conversion \a flags.
*/


/*!
    Saves the pixmap to the file with the given \a fileName using the
    specified image file \a format and \a quality factor. Returns true
    if successful; otherwise returns false.

    The \a quality factor must be in the range [0,100] or -1. Specify
    0 to obtain small compressed files, 100 for large uncompressed
    files, and -1 to use the default settings.

    If \a format is 0, an image format will be chosen from \a fileName's
    suffix.

    \sa {QPixmap#Reading and Writing Image Files}{Reading and Writing
    Image Files}
*/

bool QPixmap::save(const QString &fileName, const char *format, int quality) const
{
    if (isNull())
        return false;                                // nothing to save
    QImageWriter writer(fileName, format);
    return doImageIO(&writer, quality);
}

/*!
    \overload

    This function writes a QPixmap to the given \a device using the
    specified image file \a format and \a quality factor. This can be
    used, for example, to save a pixmap directly into a QByteArray:

    \snippet doc/src/snippets/image/image.cpp 1
*/

bool QPixmap::save(QIODevice* device, const char* format, int quality) const
{
    if (isNull())
        return false;                                // nothing to save
    QImageWriter writer(device, format);
    return doImageIO(&writer, quality);
}

/*! \internal
*/
bool QPixmap::doImageIO(QImageWriter *writer, int quality) const
{
    if (quality > 100  || quality < -1)
        qWarning("QPixmap::save: quality out of range [-1,100]");
    if (quality >= 0)
        writer->setQuality(qMin(quality,100));
    return writer->write(toImage());
}


// The implementation (and documentation) of
// QPixmap::fill(const QWidget *, const QPoint &)
// is in qwidget.cpp

/*!
    \fn void QPixmap::fill(const QWidget *widget, int x, int y)
    \overload

    Fills the pixmap with the \a widget's background color or pixmap.
    The given point, (\a x, \a y), defines an offset in widget
    coordinates to which the pixmap's top-left pixel will be mapped
    to.
*/

/*!
    Fills the pixmap with the given \a color.

    \sa {QPixmap#Pixmap Transformations}{Pixmap Transformations}
*/

void QPixmap::fill(const QColor &color)
{
    if (isNull())
        return;

    detach();
    data->fill(color);
}

/*! \obsolete
    Returns a number that identifies the contents of this QPixmap
    object. Distinct QPixmap objects can only have the same serial
    number if they refer to the same contents (but they don't have
    to).

    Use cacheKey() instead.

    \warning The serial number doesn't necessarily change when
    the pixmap is altered. This means that it may be dangerous to use
    it as a cache key. For caching pixmaps, we recommend using the
    QPixmapCache class whenever possible.
*/
int QPixmap::serialNumber() const
{
    if (isNull())
        return 0;
    return data->serialNumber();
}

/*!
    Returns a number that identifies this QPixmap. Distinct QPixmap
    objects can only have the same cache key if they refer to the same
    contents.

    The cacheKey() will change when the pixmap is altered.
*/
qint64 QPixmap::cacheKey() const
{
    int classKey = data->classId();
    if (classKey >= 1024)
        classKey = -(classKey >> 10);
    return ((((qint64) classKey) << 56)
            | (((qint64) data->serialNumber()) << 32)
            | ((qint64) (data->detach_no)));
}

static void sendResizeEvents(QWidget *target)
{
    QResizeEvent e(target->size(), QSize());
    QApplication::sendEvent(target, &e);

    const QObjectList children = target->children();
    for (int i = 0; i < children.size(); ++i) {
        QWidget *child = static_cast<QWidget*>(children.at(i));
        if (child->isWidgetType() && !child->isWindow() && child->testAttribute(Qt::WA_PendingResizeEvent))
            sendResizeEvents(child);
    }
}

/*!
    \fn QPixmap QPixmap::grabWidget(QWidget * widget, const QRect &rectangle)

    Creates a pixmap and paints the given \a widget, restricted by the
    given \a rectangle, in it. If the \a widget has any children, then
    they are also painted in the appropriate positions.

    If no rectangle is specified (the default) the entire widget is
    painted.

    If \a widget is 0, the specified rectangle doesn't overlap the
    widget's rectangle, or an error occurs, the function will return a
    null QPixmap.  If the rectangle is a superset of the given \a
    widget, the areas outside the \a widget are covered with the
    widget's background.

    This function actually asks \a widget to paint itself (and its
    children to paint themselves) by calling paintEvent() with painter
    redirection turned on. But QPixmap also provides the grabWindow()
    function which is a bit faster by grabbing pixels directly off the
    screen. In addition, if there are overlaying windows,
    grabWindow(), unlike grabWidget(), will see them.

    \warning Do not grab a widget from its QWidget::paintEvent().
    However, it is safe to grab a widget from another widget's
    \l {QWidget::}{paintEvent()}.

    \sa grabWindow()
*/

QPixmap QPixmap::grabWidget(QWidget * widget, const QRect &rect)
{
    if (!widget)
        return QPixmap();

    if (widget->testAttribute(Qt::WA_PendingResizeEvent) || !widget->testAttribute(Qt::WA_WState_Created))
        sendResizeEvents(widget);

    QRect r(rect);
    if (r.width() < 0)
        r.setWidth(widget->width() - rect.x());
    if (r.height() < 0)
        r.setHeight(widget->height() - rect.y());

    if (!r.intersects(widget->rect()))
        return QPixmap();

    QPixmap res(r.size());
    widget->render(&res, QPoint(), r,
                   QWidget::DrawWindowBackground | QWidget::DrawChildren | QWidget::IgnoreMask);
    return res;
}

/*!
    \fn QPixmap QPixmap::grabWidget(QWidget *widget, int x, int y, int
    width, int height)

    \overload

    Creates a pixmap and paints the given \a widget, restricted by
    QRect(\a x, \a y, \a width, \a height), in it.

    \warning Do not grab a widget from its QWidget::paintEvent().
    However, it is safe to grab a widget from another widget's
    \l {QWidget::}{paintEvent()}.
*/


/*!
    \since 4.5

    \enum QPixmap::ShareMode

    This enum type defines the share modes that are available when
    creating a QPixmap object from a raw X11 Pixmap handle.

    \value ImplicitlyShared  This mode will cause the QPixmap object to
    create a copy of the internal data before it is modified, thus
    keeping the original X11 pixmap intact.

    \value ExplicitlyShared  In this mode, the pixmap data will \e not be
    copied before it is modified, which in effect will change the
    original X11 pixmap.

    \warning This enum is only used for X11 specific functions; using
    it is non-portable.

    \sa QPixmap::fromX11Pixmap()
*/

/*!
    \since 4.5

    \fn QPixmap QPixmap::fromX11Pixmap(Qt::HANDLE pixmap, QPixmap::ShareMode mode)

    Creates a QPixmap from the native X11 Pixmap handle \a pixmap,
    using \a mode as the share mode. The default share mode is
    QPixmap::ImplicitlyShared, which means that a copy of the pixmap is
    made if someone tries to modify it by e.g. drawing onto it.

    QPixmap does \e not take ownership of the \a pixmap handle, and
    have to be deleted by the user.

    \warning This function is X11 specific; using it is non-portable.

    \sa QPixmap::ShareMode
*/


#if defined(Q_WS_X11) || defined(Q_WS_QWS)

/*!
    Returns the pixmap's handle to the device context.

    Note that, since QPixmap make use of \l {Implicit Data
    Sharing}{implicit data sharing}, the detach() function must be
    called explicitly to ensure that only \e this pixmap's data is
    modified if the pixmap data is shared.

    \warning This function is X11 specific; using it is non-portable.

    \sa detach()
*/

Qt::HANDLE QPixmap::handle() const
{
#if defined(Q_WS_X11)
    if (data->classId() == QPixmapData::X11Class)
        return static_cast<QX11PixmapData*>(data)->handle();
#endif
    return 0;
}
#endif


#ifdef QT3_SUPPORT
static Qt::ImageConversionFlags colorModeToFlags(QPixmap::ColorMode mode)
{
    Qt::ImageConversionFlags flags = Qt::AutoColor;
    switch (mode) {
      case QPixmap::Color:
        flags |= Qt::ColorOnly;
        break;
      case QPixmap::Mono:
        flags |= Qt::MonoOnly;
        break;
      default:
        break;// Nothing.
    }
    return flags;
}

/*!
    Use the constructor that takes a Qt::ImageConversionFlag instead.
*/

QPixmap::QPixmap(const QString& fileName, const char *format, ColorMode mode)
    : QPaintDevice()
{
    init(0, 0, QPixmapData::PixmapType);
    if (!qt_pixmap_thread_test())
        return;

    load(fileName, format, colorModeToFlags(mode));
}

/*!
    Constructs a pixmap from the QImage \a image.

    Use the static fromImage() function instead.
*/
QPixmap::QPixmap(const QImage& image)
    : QPaintDevice()
{
    init(0, 0, QPixmapData::PixmapType);
    if (!qt_pixmap_thread_test())
        return;

    if (data->pixelType() == QPixmapData::BitmapType)
        *this = QBitmap::fromImage(image);
    else
        *this = fromImage(image);
}

/*!
    \overload

    Converts the given \a image to a pixmap that is assigned to this
    pixmap.

    Use the static fromImage() function instead.
*/

QPixmap &QPixmap::operator=(const QImage &image)
{
    if (data->pixelType() == QPixmapData::BitmapType)
        *this = QBitmap::fromImage(image);
    else
        *this = fromImage(image);
    return *this;
}

/*!
    Use the load() function that takes a Qt::ImageConversionFlag instead.