source: trunk/src/gui/kernel/qx11info_x11.cpp@ 322

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#include "qwidget.h"
#include "qpixmap.h"
#include "qx11info_x11.h"
#include "qt_x11_p.h"

QT_BEGIN_NAMESPACE

/*!
    \class QX11Info
    \brief The QX11Info class provides information about the X display
    configuration.

    \ingroup shared

    The class provides two APIs: a set of non-static functions that
    provide information about a specific widget or pixmap, and a set
    of static functions that provide the default information for the
    application.

    \warning This class is only available on X11. For querying
    per-screen information in a portable way, use QDesktopWidget.

    \sa QWidget::x11Info(), QPixmap::x11Info(), QDesktopWidget
*/

/*!
    Constructs an empty QX11Info object.
*/
QX11Info::QX11Info()
    : x11data(0)
{
}

/*!
    Constructs a copy of \a other.
*/
QX11Info::QX11Info(const QX11Info &other)
{
    x11data = other.x11data;
    if (x11data)
        ++x11data->ref;
}

/*!
    Assigns \a other to this object and returns a reference to this
    object.
*/
QX11Info &QX11Info::operator=(const QX11Info &other)
{
    if (other.x11data)
        ++other.x11data->ref;
    if (x11data && !--x11data->ref)
        delete x11data;
    x11data = other.x11data;
    return *this;
}

/*!
    Destroys the QX11Info object.
*/
QX11Info::~QX11Info()
{
    if (x11data && !--x11data->ref)
        delete x11data;
}

/*!
    \internal
    Makes a shallow copy of the X11-specific data of \a fromDevice, if it is not
    null. Otherwise this function sets it to null.
*/

void QX11Info::copyX11Data(const QPaintDevice *fromDevice)
{
    QX11InfoData *xd = 0;
    if (fromDevice) {
        if (fromDevice->devType() == QInternal::Widget)
            xd = static_cast<const QWidget *>(fromDevice)->x11Info().x11data;
        else if (fromDevice->devType() == QInternal::Pixmap)
            xd = static_cast<const QPixmap *>(fromDevice)->x11Info().x11data;
    }
    setX11Data(xd);
}

/*!
    \internal
    Makes a deep copy of the X11-specific data of \a fromDevice, if it is not
    null. Otherwise this function sets it to null.
*/

void QX11Info::cloneX11Data(const QPaintDevice *fromDevice)
{
    QX11InfoData *d = 0;
    if (fromDevice) {
        QX11InfoData *xd;
        if (fromDevice->devType() == QInternal::Widget) {
            xd = static_cast<const QWidget *>(fromDevice)->x11Info().x11data;
        } else {
            Q_ASSERT(fromDevice->devType() == QInternal::Pixmap);
            xd = static_cast<const QPixmap *>(fromDevice)->x11Info().x11data;
        }
        d = new QX11InfoData(*xd);
        d->ref = 0;
    }
    setX11Data(d);
}

/*!
    \internal
    Makes a shallow copy of the X11-specific data \a d and assigns it to this
    class. This function increments the reference code of \a d.
*/

void QX11Info::setX11Data(const QX11InfoData* d)
{
    if (x11data && !--x11data->ref)
        delete x11data;
    x11data = (QX11InfoData *)d;
    if (x11data)
        ++x11data->ref;
}


/*!
    \internal
    If \a def is false, returns a deep copy of the x11Data, or 0 if x11Data is 0.
    If \a def is true, makes a QX11Data struct filled with the default
    values.

    In either case the caller is responsible for deleting the returned
    struct. But notice that the struct is a shared class, so other
    classes might also have a reference to it. The reference count of
    the returned QX11Data* is 0.
*/

QX11InfoData* QX11Info::getX11Data(bool def) const
{
    QX11InfoData* res = 0;
    if (def) {
        res = new QX11InfoData;
        res->screen = appScreen();
        res->depth = appDepth();
        res->cells = appCells();
        res->colormap = colormap();
        res->defaultColormap = appDefaultColormap();
        res->visual = (Visual*) appVisual();
        res->defaultVisual = appDefaultVisual();
    } else if (x11data) {
        res = new QX11InfoData;
        *res = *x11data;
    }
    res->ref = 0;
    return res;
}

/*!
    Returns the horizontal resolution of the given \a screen in terms of the
    number of dots per inch.

    The \a screen argument is an X screen number. Be aware that if
    the user's system uses Xinerama (as opposed to traditional X11
    multiscreen), there is only one X screen. Use QDesktopWidget to
    query for information about Xinerama screens.

    \sa setAppDpiX(), appDpiY()
*/
int QX11Info::appDpiX(int screen)
{
    if (!X11)
        return 75;
    if (screen < 0)
        screen = X11->defaultScreen;
    if (screen > X11->screenCount)
        return 0;