qpixmap.cpp

奇趣公司比较新的qt/emd版本

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#include <qglobal.h>

#include "qpixmap.h"
#include "qpixmap_p.h"

#include "qbitmap.h"
#include "qimage.h"
#include "qwidget.h"
#include "qpainter.h"
#include "qdatastream.h"
#include "qbuffer.h"
#include "qapplication.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"

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

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

// ### 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();
}

/*!
    \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()
{
    init(0, 0);
}

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

    Constructs a pixmap with the given \a width and \a height.

    The content of the pixmap is uninitialized.  If either \a width or
    \a height is zero, a null pixmap is constructed.

    \sa isNull()
*/

QPixmap::QPixmap(int w, int h)
    : QPaintDevice()
{
    init(w, h);
}

/*!
    \overload

    Constructs a pixmap of the given \a size.
*/

QPixmap::QPixmap(const QSize &size)
    : QPaintDevice()
{
    init(size.width(), size.height());
}

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

/*!
    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);
    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 (pixmap.paintingActive()) {                // make a deep copy
        data = 0;
        operator=(pixmap.copy());
    } else {
        data = pixmap.data;
        data->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:

    \code
        static const char * const start_xpm[]={
            "16 15 8 1",
            "a c #cec6bd",
        ....
    \endcode

    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.
*/

QPixmap::QPixmap(const char * const xpm[])
    : QPaintDevice()
{
    init(0, 0);
    if (!xpm)
        return;

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



/*!
    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}
*/

#if defined(Q_WS_WIN) || defined(Q_WS_QWS)
QPixmap QPixmap::copy(const QRect &rect) const
{
    QPixmap pm;
    if (data->type == BitmapType)
        pm = QBitmap::fromImage(toImage().copy(rect));
    else
        pm = fromImage(toImage().copy(rect));
    return pm;
}
#endif

/*!
    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();                                // 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.
*/

/*!
    \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.
*/

/*!
    \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->w == 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->w;
}

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

    Returns the height of the pixmap.

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

/*!
    \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->w,data->h);
}

/*!
    \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->w,data->h);
}

/*!
    \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->d;
}

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

    Use the QPixmap constructor that takes a QSize (\a size) instead.

    \oldcode
        pixmap.resize(size);
    \newcode
        pixmap = QPixmap(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;
    }