/****************************************************************************+
−
**+
−
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).+
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** All rights reserved.+
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** Contact: Nokia Corporation (qt-info@nokia.com)+
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**+
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** This file is part of the QtGui module of the Qt Toolkit.+
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**+
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** $QT_BEGIN_LICENSE:LGPL$+
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** No Commercial Usage+
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** This file contains pre-release code and may not be distributed.+
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** You may use this file in accordance with the terms and conditions+
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** contained in the Technology Preview License Agreement accompanying+
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** this package.+
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**+
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** GNU Lesser General Public License Usage+
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** Alternatively, this file may be used under the terms of the GNU Lesser+
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** General Public License version 2.1 as published by the Free Software+
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** Foundation and appearing in the file LICENSE.LGPL included in the+
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** packaging of this file.  Please review the following information to+
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** ensure the GNU Lesser General Public License version 2.1 requirements+
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** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.+
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**+
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** In addition, as a special exception, Nokia gives you certain additional+
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** rights.  These rights are described in the Nokia Qt LGPL Exception+
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** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.+
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** If you have questions regarding the use of this file, please contact+
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** Nokia at qt-info@nokia.com.+
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**+
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**+
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** $QT_END_LICENSE$+
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**+
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****************************************************************************/+
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+
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#include "qfont.h"+
−
#include "qpaintdevice.h"+
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#include "qfontmetrics.h"+
−
+
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#include "qfont_p.h"+
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#include "qfontengine_p.h"+
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#include <private/qunicodetables_p.h>+
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+
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#include <math.h>+
−
+
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#ifdef Q_WS_X11+
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#include "qx11info_x11.h"+
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#endif+
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+
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QT_BEGIN_NAMESPACE+
−
+
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#ifdef Q_WS_X11+
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extern const QX11Info *qt_x11Info(const QPaintDevice *pd);+
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#endif+
−
+
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extern void qt_format_text(const QFont& font, const QRectF &_r,+
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                           int tf, const QString &text, QRectF *brect,+
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                           int tabStops, int *tabArray, int tabArrayLen,+
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                           QPainter *painter);+
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extern int qt_defaultDpi();+
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+
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/*****************************************************************************+
−
  QFontMetrics member functions+
−
 *****************************************************************************/+
−
+
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/*!+
−
    \class QFontMetrics+
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    \reentrant+
−
+
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    \brief The QFontMetrics class provides font metrics information.+
−
+
−
    \ingroup painting+
−
    \ingroup shared+
−
+
−
    QFontMetrics functions calculate the size of characters and+
−
    strings for a given font. There are three ways you can create a+
−
    QFontMetrics object:+
−
+
−
    \list 1+
−
    \o Calling the QFontMetrics constructor with a QFont creates a+
−
    font metrics object for a screen-compatible font, i.e. the font+
−
    cannot be a printer font. If the font is changed+
−
    later, the font metrics object is \e not updated.+
−
+
−
    (Note: If you use a printer font the values returned may be+
−
    inaccurate. Printer fonts are not always accessible so the nearest+
−
    screen font is used if a printer font is supplied.)+
−
+
−
    \o QWidget::fontMetrics() returns the font metrics for a widget's+
−
    font. This is equivalent to QFontMetrics(widget->font()). If the+
−
    widget's font is changed later, the font metrics object is \e not+
−
    updated.+
−
+
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    \o QPainter::fontMetrics() returns the font metrics for a+
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    painter's current font. If the painter's font is changed later, the+
−
    font metrics object is \e not updated.+
−
    \endlist+
−
+
−
    Once created, the object provides functions to access the+
−
    individual metrics of the font, its characters, and for strings+
−
    rendered in the font.+
−
+
−
    There are several functions that operate on the font: ascent(),+
−
    descent(), height(), leading() and lineSpacing() return the basic+
−
    size properties of the font. The underlinePos(), overlinePos(),+
−
    strikeOutPos() and lineWidth() functions, return the properties of+
−
    the line that underlines, overlines or strikes out the+
−
    characters. These functions are all fast.+
−
+
−
    There are also some functions that operate on the set of glyphs in+
−
    the font: minLeftBearing(), minRightBearing() and maxWidth().+
−
    These are by necessity slow, and we recommend avoiding them if+
−
    possible.+
−
+
−
    For each character, you can get its width(), leftBearing() and+
−
    rightBearing() and find out whether it is in the font using+
−
    inFont(). You can also treat the character as a string, and use+
−
    the string functions on it.+
−
+
−
    The string functions include width(), to return the width of a+
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    string in pixels (or points, for a printer), boundingRect(), to+
−
    return a rectangle large enough to contain the rendered string,+
−
    and size(), to return the size of that rectangle.+
−
+
−
    Example:+
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    \snippet doc/src/snippets/code/src_gui_text_qfontmetrics.cpp 0+
−
+
−
    \sa QFont, QFontInfo, QFontDatabase, QFontComboBox, {Character Map Example}+
−
*/+
−
+
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/*!+
−
    \fn QRect QFontMetrics::boundingRect(int x, int y, int width, int height,+
−
        int flags, const QString &text, int tabStops, int *tabArray) const+
−
    \overload+
−
+
−
    Returns the bounding rectangle for the given \a text within the+
−
    rectangle specified by the \a x and \a y coordinates, \a width, and+
−
    \a height.+
−
+
−
    If Qt::TextExpandTabs is set in \a flags and \a tabArray is+
−
    non-null, it specifies a 0-terminated sequence of pixel-positions+
−
    for tabs; otherwise, if \a tabStops is non-zero, it is used as the+
−
    tab spacing (in pixels).+
−
*/+
−
+
−
/*!+
−
    Constructs a font metrics object for \a font.+
−
+
−
    The font metrics will be compatible with the paintdevice used to+
−
    create \a font.+
−
+
−
    The font metrics object holds the information for the font that is+
−
    passed in the constructor at the time it is created, and is not+
−
    updated if the font's attributes are changed later.+
−
+
−
    Use QFontMetrics(const QFont &, QPaintDevice *) to get the font+
−
    metrics that are compatible with a certain paint device.+
−
*/+
−
QFontMetrics::QFontMetrics(const QFont &font)+
−
    : d(font.d.data())+
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{+
−
    d->ref.ref();+
−
}+
−
+
−
/*!+
−
    Constructs a font metrics object for \a font and \a paintdevice.+
−
+
−
    The font metrics will be compatible with the paintdevice passed.+
−
    If the \a paintdevice is 0, the metrics will be screen-compatible,+
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    ie. the metrics you get if you use the font for drawing text on a+
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    \link QWidget widgets\endlink or \link QPixmap pixmaps\endlink,+
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    not on a QPicture or QPrinter.+
−
+
−
    The font metrics object holds the information for the font that is+
−
    passed in the constructor at the time it is created, and is not+
−
    updated if the font's attributes are changed later.+
−
*/+
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QFontMetrics::QFontMetrics(const QFont &font, QPaintDevice *paintdevice)+
−
{+
−
    int dpi = paintdevice ? paintdevice->logicalDpiY() : qt_defaultDpi();+
−
#ifdef Q_WS_X11+
−
    const QX11Info *info = qt_x11Info(paintdevice);+
−
    int screen = info ? info->screen() : 0;+
−
#else+
−
    const int screen = 0;+
−
#endif+
−
    if (font.d->dpi != dpi || font.d->screen != screen ) {+
−
        d = new QFontPrivate(*font.d);+
−
        d->dpi = dpi;+
−
        d->screen = screen;+
−
    } else {+
−
        d = font.d.data();+
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        d->ref.ref();+
−
    }+
−
+
−
}+
−
+
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/*!+
−
    Constructs a copy of \a fm.+
−
*/+
−
QFontMetrics::QFontMetrics(const QFontMetrics &fm)+
−
    : d(fm.d)+
−
{ d->ref.ref(); }+
−
+
−
/*!+
−
    Destroys the font metrics object and frees all allocated+
−
    resources.+
−
*/+
−
QFontMetrics::~QFontMetrics()+
−
{+
−
    if (!d->ref.deref())+
−
        delete d;+
−
}+
−
+
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/*!+
−
    Assigns the font metrics \a fm.+
−
*/+
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QFontMetrics &QFontMetrics::operator=(const QFontMetrics &fm)+
−
{+
−
    qAtomicAssign(d, fm.d);+
−
    return *this;+
−
}+
−
+
−
/*!+
−
    \overload+
−
    Returns true if \a other is equal to this object; otherwise+
−
    returns false.+
−
+
−
    Two font metrics are considered equal if they were constructed+
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    from the same QFont and the paint devices they were constructed+
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    for are considered compatible.+
−
+
−
    \sa operator!=()+
−
*/+
−
bool QFontMetrics::operator ==(const QFontMetrics &other) const+
−
{+
−
    return d == other.d;+
−
}+
−
+
−
/*!+
−
    Returns true if \a other is equal to this object; otherwise+
−
    returns false.+
−
+
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    Two font metrics are considered equal if they were constructed+
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    from the same QFont and the paint devices they were constructed+
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    for are considered compatible.+
−
+
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    \sa operator!=()+
−
*/+
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bool QFontMetrics::operator ==(const QFontMetrics &other)+
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{+
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    return d == other.d;+
−
}+
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+
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/*!+
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    \fn bool QFontMetrics::operator!=(const QFontMetrics &other)+
−
+
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    Returns true if \a other is not equal to this object; otherwise returns false.+
−
+
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    Two font metrics are considered equal if they were constructed+
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    from the same QFont and the paint devices they were constructed+
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    for are considered compatible.+
−
+
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    \sa operator==()+
−
*/+
−
+
−
/*!+
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    \fn bool QFontMetrics::operator !=(const QFontMetrics &other) const+
−
+
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    Returns true if \a other is not equal to this object; otherwise returns false.+
−
+
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    Two font metrics are considered equal if they were constructed+
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    from the same QFont and the paint devices they were constructed+
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    for are considered compatible.+
−
+
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    \sa operator==()+
−
*/+
−
+
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/*!+
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    Returns the ascent of the font.+
−
+
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    The ascent of a font is the distance from the baseline to the+
−
    highest position characters extend to. In practice, some font+
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    designers break this rule, e.g. when they put more than one accent+
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    on top of a character, or to accommodate an unusual character in+
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    an exotic language, so it is possible (though rare) that this+
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    value will be too small.+
−
+
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    \sa descent()+
−
*/+
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int QFontMetrics::ascent() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
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    Q_ASSERT(engine != 0);+
−
    return qRound(engine->ascent());+
−
}+
−
+
−
+
−
/*!+
−
    Returns the descent of the font.+
−
+
−
    The descent is the distance from the base line to the lowest point+
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    characters extend to. In practice, some font designers break this rule,+
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    e.g. to accommodate an unusual character in an exotic language, so+
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    it is possible (though rare) that this value will be too small.+
−
+
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    \sa ascent()+
−
*/+
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int QFontMetrics::descent() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
    return qRound(engine->descent());+
−
}+
−
+
−
/*!+
−
    Returns the height of the font.+
−
+
−
    This is always equal to ascent()+descent()+1 (the 1 is for the+
−
    base line).+
−
+
−
    \sa leading(), lineSpacing()+
−
*/+
−
int QFontMetrics::height() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
    return qRound(engine->ascent() + engine->descent()) + 1;+
−
}+
−
+
−
/*!+
−
    Returns the leading of the font.+
−
+
−
    This is the natural inter-line spacing.+
−
+
−
    \sa height(), lineSpacing()+
−
*/+
−
int QFontMetrics::leading() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
    return qRound(engine->leading());+
−
}+
−
+
−
/*!+
−
    Returns the distance from one base line to the next.+
−
+
−
    This value is always equal to leading()+height().+
−
+
−
    \sa height(), leading()+
−
*/+
−
int QFontMetrics::lineSpacing() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
    return qRound(engine->leading() + engine->ascent() + engine->descent()) + 1;+
−
}+
−
+
−
/*!+
−
    Returns the minimum left bearing of the font.+
−
+
−
    This is the smallest leftBearing(char) of all characters in the+
−
    font.+
−
+
−
    Note that this function can be very slow if the font is large.+
−
+
−
    \sa minRightBearing(), leftBearing()+
−
*/+
−
int QFontMetrics::minLeftBearing() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
    return qRound(engine->minLeftBearing());+
−
}+
−
+
−
/*!+
−
    Returns the minimum right bearing of the font.+
−
+
−
    This is the smallest rightBearing(char) of all characters in the+
−
    font.+
−
+
−
    Note that this function can be very slow if the font is large.+
−
+
−
    \sa minLeftBearing(), rightBearing()+
−
*/+
−
int QFontMetrics::minRightBearing() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
    return qRound(engine->minRightBearing());+
−
}+
−
+
−
/*!+
−
    Returns the width of the widest character in the font.+
−
*/+
−
int QFontMetrics::maxWidth() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
    return qRound(engine->maxCharWidth());+
−
}+
−
+
−
/*!+
−
    Returns the 'x' height of the font. This is often but not always+
−
    the same as the height of the character 'x'.+
−
*/+
−
int QFontMetrics::xHeight() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
    if (d->capital == QFont::SmallCaps)+
−
        return qRound(d->smallCapsFontPrivate()->engineForScript(QUnicodeTables::Common)->ascent());+
−
    return qRound(engine->xHeight());+
−
}+
−
+
−
/*!+
−
    \since 4.2+
−
+
−
    Returns the average width of glyphs in the font.+
−
*/+
−
int QFontMetrics::averageCharWidth() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
    return qRound(engine->averageCharWidth());+
−
}+
−
+
−
/*!+
−
    Returns true if character \a ch is a valid character in the font;+
−
    otherwise returns false.+
−
*/+
−
bool QFontMetrics::inFont(QChar ch) const+
−
{+
−
    const int script = QUnicodeTables::script(ch);+
−
    QFontEngine *engine = d->engineForScript(script);+
−
    Q_ASSERT(engine != 0);+
−
    if (engine->type() == QFontEngine::Box)+
−
        return false;+
−
    return engine->canRender(&ch, 1);+
−
}+
−
+
−
/*!+
−
    Returns the left bearing of character \a ch in the font.+
−
+
−
    The left bearing is the right-ward distance of the left-most pixel+
−
    of the character from the logical origin of the character. This+
−
    value is negative if the pixels of the character extend to the+
−
    left of the logical origin.+
−
+
−
    See width(QChar) for a graphical description of this metric.+
−
+
−
    \sa rightBearing(), minLeftBearing(), width()+
−
*/+
−
int QFontMetrics::leftBearing(QChar ch) const+
−
{+
−
    const int script = QUnicodeTables::script(ch);+
−
    QFontEngine *engine;+
−
    if (d->capital == QFont::SmallCaps && ch.isLower())+
−
        engine = d->smallCapsFontPrivate()->engineForScript(script);+
−
    else+
−
        engine = d->engineForScript(script);+
−
    Q_ASSERT(engine != 0);+
−
    if (engine->type() == QFontEngine::Box)+
−
        return 0;+
−
+
−
    d->alterCharForCapitalization(ch);+
−
+
−
    QGlyphLayoutArray<10> glyphs;+
−
    int nglyphs = 9;+
−
    engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, 0);+
−
    // ### can nglyphs != 1 happen at all? Not currently I think+
−
    glyph_metrics_t gi = engine->boundingBox(glyphs.glyphs[0]);+
−
    return qRound(gi.x);+
−
}+
−
+
−
/*!+
−
    Returns the right bearing of character \a ch in the font.+
−
+
−
    The right bearing is the left-ward distance of the right-most+
−
    pixel of the character from the logical origin of a subsequent+
−
    character. This value is negative if the pixels of the character+
−
    extend to the right of the width() of the character.+
−
+
−
    See width() for a graphical description of this metric.+
−
+
−
    \sa leftBearing(), minRightBearing(), width()+
−
*/+
−
int QFontMetrics::rightBearing(QChar ch) const+
−
{+
−
    const int script = QUnicodeTables::script(ch);+
−
    QFontEngine *engine;+
−
    if (d->capital == QFont::SmallCaps && ch.isLower())+
−
        engine = d->smallCapsFontPrivate()->engineForScript(script);+
−
    else+
−
        engine = d->engineForScript(script);+
−
    Q_ASSERT(engine != 0);+
−
    if (engine->type() == QFontEngine::Box)+
−
        return 0;+
−
+
−
    d->alterCharForCapitalization(ch);+
−
+
−
    QGlyphLayoutArray<10> glyphs;+
−
    int nglyphs = 9;+
−
    engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, 0);+
−
    // ### can nglyphs != 1 happen at all? Not currently I think+
−
    glyph_metrics_t gi = engine->boundingBox(glyphs.glyphs[0]);+
−
    return qRound(gi.xoff - gi.x - gi.width);+
−
}+
−
+
−
/*!+
−
    Returns the width in pixels of the first \a len characters of \a+
−
    text. If \a len is negative (the default), the entire string is+
−
    used.+
−
+
−
    Note that this value is \e not equal to boundingRect().width();+
−
    boundingRect() returns a rectangle describing the pixels this+
−
    string will cover whereas width() returns the distance to where+
−
    the next string should be drawn.+
−
+
−
    \sa boundingRect()+
−
*/+
−
int QFontMetrics::width(const QString &text, int len) const+
−
{+
−
    int pos = text.indexOf(QLatin1Char('\x9c'));+
−
    if (pos != -1) {+
−
        len = (len < 0) ? pos : qMin(pos, len);+
−
    } else if (len < 0) {+
−
        len = text.length();+
−
    }+
−
    if (len == 0)+
−
        return 0;+
−
+
−
    QTextEngine layout(text, d);+
−
    layout.ignoreBidi = true;+
−
    return qRound(layout.width(0, len));+
−
}+
−
+
−
/*!+
−
    \overload+
−
+
−
    \img bearings.png Bearings+
−
+
−
    Returns the logical width of character \a ch in pixels. This is a+
−
    distance appropriate for drawing a subsequent character after \a+
−
    ch.+
−
+
−
    Some of the metrics are described in the image to the right. The+
−
    central dark rectangles cover the logical width() of each+
−
    character. The outer pale rectangles cover the leftBearing() and+
−
    rightBearing() of each character. Notice that the bearings of "f"+
−
    in this particular font are both negative, while the bearings of+
−
    "o" are both positive.+
−
+
−
    \warning This function will produce incorrect results for Arabic+
−
    characters or non-spacing marks in the middle of a string, as the+
−
    glyph shaping and positioning of marks that happens when+
−
    processing strings cannot be taken into account. When implementing+
−
    an interactive text control, use QTextLayout instead.+
−
+
−
    \sa boundingRect()+
−
*/+
−
int QFontMetrics::width(QChar ch) const+
−
{+
−
    if (QChar::category(ch.unicode()) == QChar::Mark_NonSpacing)+
−
        return 0;+
−
+
−
    const int script = QUnicodeTables::script(ch);+
−
    QFontEngine *engine;+
−
    if (d->capital == QFont::SmallCaps && ch.isLower())+
−
        engine = d->smallCapsFontPrivate()->engineForScript(script);+
−
    else+
−
        engine = d->engineForScript(script);+
−
    Q_ASSERT(engine != 0);+
−
+
−
    d->alterCharForCapitalization(ch);+
−
+
−
    QGlyphLayoutArray<8> glyphs;+
−
    int nglyphs = 7;+
−
    engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, 0);+
−
    return qRound(glyphs.advances_x[0]);+
−
}+
−
+
−
/*! \obsolete+
−
+
−
    Returns the width of the character at position \a pos in the+
−
    string \a text.+
−
+
−
    The whole string is needed, as the glyph drawn may change+
−
    depending on the context (the letter before and after the current+
−
    one) for some languages (e.g. Arabic).+
−
+
−
    This function also takes non spacing marks and ligatures into+
−
    account.+
−
*/+
−
int QFontMetrics::charWidth(const QString &text, int pos) const+
−
{+
−
    if (pos < 0 || pos > (int)text.length())+
−
        return 0;+
−
+
−
    QChar ch = text.unicode()[pos];+
−
    const int script = QUnicodeTables::script(ch);+
−
    int width;+
−
+
−
    if (script != QUnicodeTables::Common) {+
−
        // complex script shaping. Have to do some hard work+
−
        int from = qMax(0, pos - 8);+
−
        int to = qMin(text.length(), pos + 8);+
−
        QString cstr = QString::fromRawData(text.unicode() + from, to - from);+
−
        QTextEngine layout(cstr, d);+
−
        layout.ignoreBidi = true;+
−
        layout.itemize();+
−
        width = qRound(layout.width(pos-from, 1));+
−
    } else if (QChar::category(ch.unicode()) == QChar::Mark_NonSpacing) {+
−
        width = 0;+
−
    } else {+
−
        QFontEngine *engine;+
−
        if (d->capital == QFont::SmallCaps && ch.isLower())+
−
            engine = d->smallCapsFontPrivate()->engineForScript(script);+
−
        else+
−
            engine = d->engineForScript(script);+
−
        Q_ASSERT(engine != 0);+
−
+
−
        d->alterCharForCapitalization(ch);+
−
+
−
        QGlyphLayoutArray<8> glyphs;+
−
        int nglyphs = 7;+
−
        engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, 0);+
−
        width = qRound(glyphs.advances_x[0]);+
−
    }+
−
    return width;+
−
}+
−
+
−
/*!+
−
    Returns the bounding rectangle of the characters in the string+
−
    specified by \a text. The bounding rectangle always covers at least+
−
    the set of pixels the text would cover if drawn at (0, 0).+
−
+
−
    Note that the bounding rectangle may extend to the left of (0, 0),+
−
    e.g. for italicized fonts, and that the width of the returned+
−
    rectangle might be different than what the width() method returns.+
−
+
−
    If you want to know the advance width of the string (to layout+
−
    a set of strings next to each other), use width() instead.+
−
+
−
    Newline characters are processed as normal characters, \e not as+
−
    linebreaks.+
−
+
−
    The height of the bounding rectangle is at least as large as the+
−
    value returned by height().+
−
+
−
    \sa width(), height(), QPainter::boundingRect(), tightBoundingRect()+
−
*/+
−
QRect QFontMetrics::boundingRect(const QString &text) const+
−
{+
−
    if (text.length() == 0)+
−
        return QRect();+
−
+
−
    QTextEngine layout(text, d);+
−
    layout.ignoreBidi = true;+
−
    layout.itemize();+
−
    glyph_metrics_t gm = layout.boundingBox(0, text.length());+
−
    return QRect(qRound(gm.x), qRound(gm.y), qRound(gm.width), qRound(gm.height));+
−
}+
−
+
−
/*!+
−
    Returns the rectangle that is covered by ink if character \a ch+
−
    were to be drawn at the origin of the coordinate system.+
−
+
−
    Note that the bounding rectangle may extend to the left of (0, 0)+
−
    (e.g., for italicized fonts), and that the text output may cover \e+
−
    all pixels in the bounding rectangle. For a space character the rectangle+
−
    will usually be empty.+
−
+
−
    Note that the rectangle usually extends both above and below the+
−
    base line.+
−
+
−
    \warning The width of the returned rectangle is not the advance width+
−
    of the character. Use boundingRect(const QString &) or width() instead.+
−
+
−
    \sa width()+
−
*/+
−
QRect QFontMetrics::boundingRect(QChar ch) const+
−
{+
−
    const int script = QUnicodeTables::script(ch);+
−
    QFontEngine *engine;+
−
    if (d->capital == QFont::SmallCaps && ch.isLower())+
−
        engine = d->smallCapsFontPrivate()->engineForScript(script);+
−
    else+
−
        engine = d->engineForScript(script);+
−
    Q_ASSERT(engine != 0);+
−
+
−
    d->alterCharForCapitalization(ch);+
−
+
−
    QGlyphLayoutArray<10> glyphs;+
−
    int nglyphs = 9;+
−
    engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, 0);+
−
    glyph_metrics_t gm = engine->boundingBox(glyphs.glyphs[0]);+
−
    return QRect(qRound(gm.x), qRound(gm.y), qRound(gm.width), qRound(gm.height));+
−
}+
−
+
−
/*!+
−
    \overload+
−
+
−
    Returns the bounding rectangle of the characters in the string+
−
    specified by \a text, which is the set of pixels the text would+
−
    cover if drawn at (0, 0). The drawing, and hence the bounding+
−
    rectangle, is constrained to the rectangle \a rect.+
−
+
−
    The \a flags argument is the bitwise OR of the following flags:+
−
    \list+
−
    \o Qt::AlignLeft aligns to the left border, except for+
−
          Arabic and Hebrew where it aligns to the right.+
−
    \o Qt::AlignRight aligns to the right border, except for+
−
          Arabic and Hebrew where it aligns to the left.+
−
    \o Qt::AlignJustify produces justified text.+
−
    \o Qt::AlignHCenter aligns horizontally centered.+
−
    \o Qt::AlignTop aligns to the top border.+
−
    \o Qt::AlignBottom aligns to the bottom border.+
−
    \o Qt::AlignVCenter aligns vertically centered+
−
    \o Qt::AlignCenter (== \c{Qt::AlignHCenter | Qt::AlignVCenter})+
−
    \o Qt::TextSingleLine ignores newline characters in the text.+
−
    \o Qt::TextExpandTabs expands tabs (see below)+
−
    \o Qt::TextShowMnemonic interprets "&x" as \underline{x}; i.e., underlined.+
−
    \o Qt::TextWordWrap breaks the text to fit the rectangle.+
−
    \endlist+
−
+
−
    Qt::Horizontal alignment defaults to Qt::AlignLeft and vertical+
−
    alignment defaults to Qt::AlignTop.+
−
+
−
    If several of the horizontal or several of the vertical alignment+
−
    flags are set, the resulting alignment is undefined.+
−
+
−
    If Qt::TextExpandTabs is set in \a flags, then: if \a tabArray is+
−
    non-null, it specifies a 0-terminated sequence of pixel-positions+
−
    for tabs; otherwise if \a tabStops is non-zero, it is used as the+
−
    tab spacing (in pixels).+
−
+
−
    Note that the bounding rectangle may extend to the left of (0, 0),+
−
    e.g. for italicized fonts, and that the text output may cover \e+
−
    all pixels in the bounding rectangle.+
−
+
−
    Newline characters are processed as linebreaks.+
−
+
−
    Despite the different actual character heights, the heights of the+
−
    bounding rectangles of "Yes" and "yes" are the same.+
−
+
−
    The bounding rectangle returned by this function is somewhat larger+
−
    than that calculated by the simpler boundingRect() function. This+
−
    function uses the \link minLeftBearing() maximum left \endlink and+
−
    \link minRightBearing() right \endlink font bearings as is+
−
    necessary for multi-line text to align correctly. Also,+
−
    fontHeight() and lineSpacing() are used to calculate the height,+
−
    rather than individual character heights.+
−
+
−
    \sa width(), QPainter::boundingRect(), Qt::Alignment+
−
*/+
−
QRect QFontMetrics::boundingRect(const QRect &rect, int flags, const QString &text, int tabStops,+
−
                                 int *tabArray) const+
−
{+
−
    int tabArrayLen = 0;+
−
    if (tabArray)+
−
        while (tabArray[tabArrayLen])+
−
            tabArrayLen++;+
−
+
−
    QRectF rb;+
−
    QRectF rr(rect);+
−
    qt_format_text(QFont(d), rr, flags | Qt::TextDontPrint, text, &rb, tabStops, tabArray,+
−
                   tabArrayLen, 0);+
−
+
−
    return rb.toAlignedRect();+
−
}+
−
+
−
/*!+
−
    Returns the size in pixels of \a text.+
−
+
−
    The \a flags argument is the bitwise OR of the following flags:+
−
    \list+
−
    \o Qt::TextSingleLine ignores newline characters.+
−
    \o Qt::TextExpandTabs expands tabs (see below)+
−
    \o Qt::TextShowMnemonic interprets "&x" as \underline{x}; i.e., underlined.+
−
    \o Qt::TextWordBreak breaks the text to fit the rectangle.+
−
    \endlist+
−
+
−
    If Qt::TextExpandTabs is set in \a flags, then: if \a tabArray is+
−
    non-null, it specifies a 0-terminated sequence of pixel-positions+
−
    for tabs; otherwise if \a tabStops is non-zero, it is used as the+
−
    tab spacing (in pixels).+
−
+
−
    Newline characters are processed as linebreaks.+
−
+
−
    Despite the different actual character heights, the heights of the+
−
    bounding rectangles of "Yes" and "yes" are the same.+
−
+
−
    \sa boundingRect()+
−
*/+
−
QSize QFontMetrics::size(int flags, const QString &text, int tabStops, int *tabArray) const+
−
{+
−
    return boundingRect(QRect(0,0,0,0), flags | Qt::TextLongestVariant, text, tabStops, tabArray).size();+
−
}+
−
+
−
/*!+
−
  \since 4.3+
−
+
−
    Returns a tight bounding rectangle around the characters in the+
−
    string specified by \a text. The bounding rectangle always covers+
−
    at least the set of pixels the text would cover if drawn at (0,+
−
    0).+
−
+
−
    Note that the bounding rectangle may extend to the left of (0, 0),+
−
    e.g. for italicized fonts, and that the width of the returned+
−
    rectangle might be different than what the width() method returns.+
−
+
−
    If you want to know the advance width of the string (to layout+
−
    a set of strings next to each other), use width() instead.+
−
+
−
    Newline characters are processed as normal characters, \e not as+
−
    linebreaks.+
−
+
−
    \warning Calling this method is very slow on Windows.+
−
+
−
    \sa width(), height(), boundingRect()+
−
*/+
−
QRect QFontMetrics::tightBoundingRect(const QString &text) const+
−
{+
−
    if (text.length() == 0)+
−
        return QRect();+
−
+
−
    QTextEngine layout(text, d);+
−
    layout.ignoreBidi = true;+
−
    layout.itemize();+
−
    glyph_metrics_t gm = layout.tightBoundingBox(0, text.length());+
−
    return QRect(qRound(gm.x), qRound(gm.y), qRound(gm.width), qRound(gm.height));+
−
}+
−
+
−
+
−
/*!+
−
    \since 4.2+
−
+
−
    If the string \a text is wider than \a width, returns an elided+
−
    version of the string (i.e., a string with "..." in it).+
−
    Otherwise, returns the original string.+
−
+
−
    The \a mode parameter specifies whether the text is elided on the+
−
    left (e.g., "...tech"), in the middle (e.g., "Tr...ch"), or on+
−
    the right (e.g., "Trol...").+
−
+
−
    The \a width is specified in pixels, not characters.+
−
+
−
    The \a flags argument is optional and currently only supports+
−
    Qt::TextShowMnemonic as value.+
−
+
−
    The elide mark will follow the \l{Qt::LayoutDirection}{layout+
−
    direction}; it will be on the right side of the text for+
−
    right-to-left layouts, and on the left side for right-to-left+
−
    layouts. Note that this behavior is independent of the text+
−
    language.+
−
*/+
−
QString QFontMetrics::elidedText(const QString &text, Qt::TextElideMode mode, int width, int flags) const+
−
{+
−
    QString _text = text;+
−
    if (!(flags & Qt::TextLongestVariant)) {+
−
        int posA = 0;+
−
        int posB = _text.indexOf(QLatin1Char('\x9c'));+
−
        while (posB >= 0) {+
−
            QString portion = _text.mid(posA, posB - posA);+
−
            if (size(flags, portion).width() <= width)+
−
                return portion;+
−
            posA = posB + 1;+
−
            posB = _text.indexOf(QLatin1Char('\x9c'), posA);+
−
        }+
−
        _text = _text.mid(posA);+
−
    }+
−
    QStackTextEngine engine(_text, QFont(d));+
−
    return engine.elidedText(mode, width, flags);+
−
}+
−
+
−
/*!+
−
    Returns the distance from the base line to where an underscore+
−
    should be drawn.+
−
+
−
    \sa overlinePos(), strikeOutPos(), lineWidth()+
−
*/+
−
int QFontMetrics::underlinePos() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
    return qRound(engine->underlinePosition());+
−
}+
−
+
−
/*!+
−
    Returns the distance from the base line to where an overline+
−
    should be drawn.+
−
+
−
    \sa underlinePos(), strikeOutPos(), lineWidth()+
−
*/+
−
int QFontMetrics::overlinePos() const+
−
{+
−
    return ascent() + 1;+
−
}+
−
+
−
/*!+
−
    Returns the distance from the base line to where the strikeout+
−
    line should be drawn.+
−
+
−
    \sa underlinePos(), overlinePos(), lineWidth()+
−
*/+
−
int QFontMetrics::strikeOutPos() const+
−
{+
−
    int pos = ascent() / 3;+
−
    return pos > 0 ? pos : 1;+
−
}+
−
+
−
/*!+
−
    Returns the width of the underline and strikeout lines, adjusted+
−
    for the point size of the font.+
−
+
−
    \sa underlinePos(), overlinePos(), strikeOutPos()+
−
*/+
−
int QFontMetrics::lineWidth() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
    return qRound(engine->lineThickness());+
−
}+
−
+
−
+
−
+
−
+
−
/*****************************************************************************+
−
  QFontMetricsF member functions+
−
 *****************************************************************************/+
−
+
−
/*!+
−
    \class QFontMetricsF+
−
    \reentrant+
−
+
−
    \brief The QFontMetricsF class provides font metrics information.+
−
+
−
    \ingroup painting+
−
    \ingroup shared+
−
+
−
    QFontMetricsF functions calculate the size of characters and+
−
    strings for a given font. You can construct a QFontMetricsF object+
−
    with an existing QFont to obtain metrics for that font. If the+
−
    font is changed later, the font metrics object is \e not updated.+
−
+
−
    Once created, the object provides functions to access the+
−
    individual metrics of the font, its characters, and for strings+
−
    rendered in the font.+
−
+
−
    There are several functions that operate on the font: ascent(),+
−
    descent(), height(), leading() and lineSpacing() return the basic+
−
    size properties of the font. The underlinePos(), overlinePos(),+
−
    strikeOutPos() and lineWidth() functions, return the properties of+
−
    the line that underlines, overlines or strikes out the+
−
    characters. These functions are all fast.+
−
+
−
    There are also some functions that operate on the set of glyphs in+
−
    the font: minLeftBearing(), minRightBearing() and maxWidth().+
−
    These are by necessity slow, and we recommend avoiding them if+
−
    possible.+
−
+
−
    For each character, you can get its width(), leftBearing() and+
−
    rightBearing() and find out whether it is in the font using+
−
    inFont(). You can also treat the character as a string, and use+
−
    the string functions on it.+
−
+
−
    The string functions include width(), to return the width of a+
−
    string in pixels (or points, for a printer), boundingRect(), to+
−
    return a rectangle large enough to contain the rendered string,+
−
    and size(), to return the size of that rectangle.+
−
+
−
    Example:+
−
    \snippet doc/src/snippets/code/src_gui_text_qfontmetrics.cpp 1+
−
+
−
    \sa QFont QFontInfo QFontDatabase+
−
*/+
−
+
−
/*!+
−
    \since 4.2+
−
+
−
    Constructs a font metrics object with floating point precision+
−
    from the given \a fontMetrics object.+
−
*/+
−
QFontMetricsF::QFontMetricsF(const QFontMetrics &fontMetrics)+
−
    : d(fontMetrics.d)+
−
{+
−
    d->ref.ref();+
−
}+
−
+
−
/*!+
−
    \since 4.2+
−
+
−
    Assigns \a other to this object.+
−
*/+
−
QFontMetricsF &QFontMetricsF::operator=(const QFontMetrics &other)+
−
{+
−
    qAtomicAssign(d, other.d);+
−
    return *this;+
−
}+
−
+
−
/*!+
−
    Constructs a font metrics object for \a font.+
−
+
−
    The font metrics will be compatible with the paintdevice used to+
−
    create \a font.+
−
+
−
    The font metrics object holds the information for the font that is+
−
    passed in the constructor at the time it is created, and is not+
−
    updated if the font's attributes are changed later.+
−
+
−
    Use QFontMetricsF(const QFont &, QPaintDevice *) to get the font+
−
    metrics that are compatible with a certain paint device.+
−
*/+
−
QFontMetricsF::QFontMetricsF(const QFont &font)+
−
    : d(font.d.data())+
−
{+
−
    d->ref.ref();+
−
}+
−
+
−
/*!+
−
    Constructs a font metrics object for \a font and \a paintdevice.+
−
+
−
    The font metrics will be compatible with the paintdevice passed.+
−
    If the \a paintdevice is 0, the metrics will be screen-compatible,+
−
    ie. the metrics you get if you use the font for drawing text on a+
−
    \link QWidget widgets\endlink or \link QPixmap pixmaps\endlink,+
−
    not on a QPicture or QPrinter.+
−
+
−
    The font metrics object holds the information for the font that is+
−
    passed in the constructor at the time it is created, and is not+
−
    updated if the font's attributes are changed later.+
−
*/+
−
QFontMetricsF::QFontMetricsF(const QFont &font, QPaintDevice *paintdevice)+
−
{+
−
    int dpi = paintdevice ? paintdevice->logicalDpiY() : qt_defaultDpi();+
−
#ifdef Q_WS_X11+
−
    const QX11Info *info = qt_x11Info(paintdevice);+
−
    int screen = info ? info->screen() : 0;+
−
#else+
−
    const int screen = 0;+
−
#endif+
−
    if (font.d->dpi != dpi || font.d->screen != screen ) {+
−
        d = new QFontPrivate(*font.d);+
−
        d->dpi = dpi;+
−
        d->screen = screen;+
−
    } else {+
−
        d = font.d.data();+
−
        d->ref.ref();+
−
    }+
−
+
−
}+
−
+
−
/*!+
−
    Constructs a copy of \a fm.+
−
*/+
−
QFontMetricsF::QFontMetricsF(const QFontMetricsF &fm)+
−
    : d(fm.d)+
−
{ d->ref.ref(); }+
−
+
−
/*!+
−
    Destroys the font metrics object and frees all allocated+
−
    resources.+
−
*/+
−
QFontMetricsF::~QFontMetricsF()+
−
{+
−
    if (!d->ref.deref())+
−
        delete d;+
−
}+
−
+
−
/*!+
−
    Assigns the font metrics \a fm to this font metrics object.+
−
*/+
−
QFontMetricsF &QFontMetricsF::operator=(const QFontMetricsF &fm)+
−
{+
−
    qAtomicAssign(d, fm.d);+
−
    return *this;+
−
}+
−
+
−
/*!+
−
  \overload+
−
  Returns true if the font metrics are equal to the \a other font+
−
  metrics; otherwise returns false.+
−
+
−
  Two font metrics are considered equal if they were constructed from the+
−
  same QFont and the paint devices they were constructed for are+
−
  considered to be compatible.+
−
*/+
−
bool QFontMetricsF::operator ==(const QFontMetricsF &other) const+
−
{+
−
    return d == other.d;+
−
}+
−
+
−
/*!+
−
  Returns true if the font metrics are equal to the \a other font+
−
  metrics; otherwise returns false.+
−
+
−
  Two font metrics are considered equal if they were constructed from the+
−
  same QFont and the paint devices they were constructed for are+
−
  considered to be compatible.+
−
*/+
−
bool QFontMetricsF::operator ==(const QFontMetricsF &other)+
−
{+
−
    return d == other.d;+
−
}+
−
+
−
/*!+
−
    \fn bool QFontMetricsF::operator!=(const QFontMetricsF &other)+
−
+
−
    Returns true if the font metrics are not equal to the \a other font+
−
    metrics; otherwise returns false.+
−
+
−
    \sa operator==()+
−
*/+
−
+
−
/*!+
−
    \fn bool QFontMetricsF::operator !=(const QFontMetricsF &other) const+
−
    \overload+
−
+
−
    Returns true if the font metrics are not equal to the \a other font+
−
    metrics; otherwise returns false.+
−
+
−
    \sa operator==()+
−
*/+
−
+
−
/*!+
−
    Returns the ascent of the font.+
−
+
−
    The ascent of a font is the distance from the baseline to the+
−
    highest position characters extend to. In practice, some font+
−
    designers break this rule, e.g. when they put more than one accent+
−
    on top of a character, or to accommodate an unusual character in+
−
    an exotic language, so it is possible (though rare) that this+
−
    value will be too small.+
−
+
−
    \sa descent()+
−
*/+
−
qreal QFontMetricsF::ascent() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
    return engine->ascent().toReal();+
−
}+
−
+
−
+
−
/*!+
−
    Returns the descent of the font.+
−
+
−
    The descent is the distance from the base line to the lowest point+
−
    characters extend to. (Note that this is different from X, which+
−
    adds 1 pixel.) In practice, some font designers break this rule,+
−
    e.g. to accommodate an unusual character in an exotic language, so+
−
    it is possible (though rare) that this value will be too small.+
−
+
−
    \sa ascent()+
−
*/+
−
qreal QFontMetricsF::descent() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
    return engine->descent().toReal();+
−
}+
−
+
−
/*!+
−
    Returns the height of the font.+
−
+
−
    This is always equal to ascent()+descent()+1 (the 1 is for the+
−
    base line).+
−
+
−
    \sa leading(), lineSpacing()+
−
*/+
−
qreal QFontMetricsF::height() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
+
−
    return (engine->ascent() + engine->descent() + 1).toReal();+
−
}+
−
+
−
/*!+
−
    Returns the leading of the font.+
−
+
−
    This is the natural inter-line spacing.+
−
+
−
    \sa height(), lineSpacing()+
−
*/+
−
qreal QFontMetricsF::leading() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
    return engine->leading().toReal();+
−
}+
−
+
−
/*!+
−
    Returns the distance from one base line to the next.+
−
+
−
    This value is always equal to leading()+height().+
−
+
−
    \sa height(), leading()+
−
*/+
−
qreal QFontMetricsF::lineSpacing() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
    return (engine->leading() + engine->ascent() + engine->descent() + 1).toReal();+
−
}+
−
+
−
/*!+
−
    Returns the minimum left bearing of the font.+
−
+
−
    This is the smallest leftBearing(char) of all characters in the+
−
    font.+
−
+
−
    Note that this function can be very slow if the font is large.+
−
+
−
    \sa minRightBearing(), leftBearing()+
−
*/+
−
qreal QFontMetricsF::minLeftBearing() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
    return engine->minLeftBearing();+
−
}+
−
+
−
/*!+
−
    Returns the minimum right bearing of the font.+
−
+
−
    This is the smallest rightBearing(char) of all characters in the+
−
    font.+
−
+
−
    Note that this function can be very slow if the font is large.+
−
+
−
    \sa minLeftBearing(), rightBearing()+
−
*/+
−
qreal QFontMetricsF::minRightBearing() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
    return engine->minRightBearing();+
−
}+
−
+
−
/*!+
−
    Returns the width of the widest character in the font.+
−
*/+
−
qreal QFontMetricsF::maxWidth() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
    return engine->maxCharWidth();+
−
}+
−
+
−
/*!+
−
    Returns the 'x' height of the font. This is often but not always+
−
    the same as the height of the character 'x'.+
−
*/+
−
qreal QFontMetricsF::xHeight() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
    if (d->capital == QFont::SmallCaps)+
−
        return d->smallCapsFontPrivate()->engineForScript(QUnicodeTables::Common)->ascent().toReal();+
−
    return engine->xHeight().toReal();+
−
}+
−
+
−
/*!+
−
    \since 4.2+
−
+
−
    Returns the average width of glyphs in the font.+
−
*/+
−
qreal QFontMetricsF::averageCharWidth() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
    return engine->averageCharWidth().toReal();+
−
}+
−
+
−
/*!+
−
    Returns true if character \a ch is a valid character in the font;+
−
    otherwise returns false.+
−
*/+
−
bool QFontMetricsF::inFont(QChar ch) const+
−
{+
−
    const int script = QUnicodeTables::script(ch);+
−
    QFontEngine *engine = d->engineForScript(script);+
−
    Q_ASSERT(engine != 0);+
−
    if (engine->type() == QFontEngine::Box)+
−
        return false;+
−
    return engine->canRender(&ch, 1);+
−
}+
−
+
−
/*!+
−
    Returns the left bearing of character \a ch in the font.+
−
+
−
    The left bearing is the right-ward distance of the left-most pixel+
−
    of the character from the logical origin of the character. This+
−
    value is negative if the pixels of the character extend to the+
−
    left of the logical origin.+
−
+
−
    See width(QChar) for a graphical description of this metric.+
−
+
−
    \sa rightBearing(), minLeftBearing(), width()+
−
*/+
−
qreal QFontMetricsF::leftBearing(QChar ch) const+
−
{+
−
    const int script = QUnicodeTables::script(ch);+
−
    QFontEngine *engine;+
−
    if (d->capital == QFont::SmallCaps && ch.isLower())+
−
        engine = d->smallCapsFontPrivate()->engineForScript(script);+
−
    else+
−
        engine = d->engineForScript(script);+
−
    Q_ASSERT(engine != 0);+
−
    if (engine->type() == QFontEngine::Box)+
−
        return 0;+
−
+
−
    d->alterCharForCapitalization(ch);+
−
+
−
    QGlyphLayoutArray<10> glyphs;+
−
    int nglyphs = 9;+
−
    engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, 0);+
−
    // ### can nglyphs != 1 happen at all? Not currently I think+
−
    glyph_metrics_t gi = engine->boundingBox(glyphs.glyphs[0]);+
−
    return gi.x.toReal();+
−
}+
−
+
−
/*!+
−
    Returns the right bearing of character \a ch in the font.+
−
+
−
    The right bearing is the left-ward distance of the right-most+
−
    pixel of the character from the logical origin of a subsequent+
−
    character. This value is negative if the pixels of the character+
−
    extend to the right of the width() of the character.+
−
+
−
    See width() for a graphical description of this metric.+
−
+
−
    \sa leftBearing(), minRightBearing(), width()+
−
*/+
−
qreal QFontMetricsF::rightBearing(QChar ch) const+
−
{+
−
    const int script = QUnicodeTables::script(ch);+
−
    QFontEngine *engine;+
−
    if (d->capital == QFont::SmallCaps && ch.isLower())+
−
        engine = d->smallCapsFontPrivate()->engineForScript(script);+
−
    else+
−
        engine = d->engineForScript(script);+
−
    Q_ASSERT(engine != 0);+
−
    if (engine->type() == QFontEngine::Box)+
−
        return 0;+
−
+
−
    d->alterCharForCapitalization(ch);+
−
+
−
    QGlyphLayoutArray<10> glyphs;+
−
    int nglyphs = 9;+
−
    engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, 0);+
−
    // ### can nglyphs != 1 happen at all? Not currently I think+
−
    glyph_metrics_t gi = engine->boundingBox(glyphs.glyphs[0]);+
−
    return (gi.xoff - gi.x - gi.width).toReal();+
−
}+
−
+
−
/*!+
−
    Returns the width in pixels of the characters in the given \a text.+
−
+
−
    Note that this value is \e not equal to the width returned by+
−
    boundingRect().width() because boundingRect() returns a rectangle+
−
    describing the pixels this string will cover whereas width()+
−
    returns the distance to where the next string should be drawn.+
−
+
−
    \sa boundingRect()+
−
*/+
−
qreal QFontMetricsF::width(const QString &text) const+
−
{+
−
    QTextEngine layout(text, d);+
−
    layout.ignoreBidi = true;+
−
    layout.itemize();+
−
    return layout.width(0, text.length()).toReal();+
−
}+
−
+
−
/*!+
−
    \overload+
−
+
−
    \img bearings.png Bearings+
−
+
−
    Returns the logical width of character \a ch in pixels. This is a+
−
    distance appropriate for drawing a subsequent character after \a+
−
    ch.+
−
+
−
    Some of the metrics are described in the image to the right. The+
−
    central dark rectangles cover the logical width() of each+
−
    character. The outer pale rectangles cover the leftBearing() and+
−
    rightBearing() of each character. Notice that the bearings of "f"+
−
    in this particular font are both negative, while the bearings of+
−
    "o" are both positive.+
−
+
−
    \warning This function will produce incorrect results for Arabic+
−
    characters or non-spacing marks in the middle of a string, as the+
−
    glyph shaping and positioning of marks that happens when+
−
    processing strings cannot be taken into account. When implementing+
−
    an interactive text control, use QTextLayout instead.+
−
+
−
    \sa boundingRect()+
−
*/+
−
qreal QFontMetricsF::width(QChar ch) const+
−
{+
−
    if (QChar::category(ch.unicode()) == QChar::Mark_NonSpacing)+
−
        return 0.;+
−
+
−
    const int script = QUnicodeTables::script(ch);+
−
    QFontEngine *engine;+
−
    if (d->capital == QFont::SmallCaps && ch.isLower())+
−
        engine = d->smallCapsFontPrivate()->engineForScript(script);+
−
    else+
−
        engine = d->engineForScript(script);+
−
    Q_ASSERT(engine != 0);+
−
+
−
    d->alterCharForCapitalization(ch);+
−
+
−
    QGlyphLayoutArray<8> glyphs;+
−
    int nglyphs = 7;+
−
    engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, 0);+
−
    return glyphs.advances_x[0].toReal();+
−
}+
−
+
−
/*!+
−
    Returns the bounding rectangle of the characters in the string+
−
    specified by \a text. The bounding rectangle always covers at least+
−
    the set of pixels the text would cover if drawn at (0, 0).+
−
+
−
    Note that the bounding rectangle may extend to the left of (0, 0),+
−
    e.g. for italicized fonts, and that the width of the returned+
−
    rectangle might be different than what the width() method returns.+
−
+
−
    If you want to know the advance width of the string (to layout+
−
    a set of strings next to each other), use width() instead.+
−
+
−
    Newline characters are processed as normal characters, \e not as+
−
    linebreaks.+
−
+
−
    The height of the bounding rectangle is at least as large as the+
−
    value returned height().+
−
+
−
    \sa width(), height(), QPainter::boundingRect()+
−
*/+
−
QRectF QFontMetricsF::boundingRect(const QString &text) const+
−
{+
−
    int len = text.length();+
−
    if (len == 0)+
−
        return QRectF();+
−
+
−
    QTextEngine layout(text, d);+
−
    layout.ignoreBidi = true;+
−
    layout.itemize();+
−
    glyph_metrics_t gm = layout.boundingBox(0, len);+
−
    return QRectF(gm.x.toReal(), gm.y.toReal(),+
−
                  gm.width.toReal(), gm.height.toReal());+
−
}+
−
+
−
/*!+
−
    Returns the bounding rectangle of the character \a ch relative to+
−
    the left-most point on the base line.+
−
+
−
    Note that the bounding rectangle may extend to the left of (0, 0),+
−
    e.g. for italicized fonts, and that the text output may cover \e+
−
    all pixels in the bounding rectangle.+
−
+
−
    Note that the rectangle usually extends both above and below the+
−
    base line.+
−
+
−
    \sa width()+
−
*/+
−
QRectF QFontMetricsF::boundingRect(QChar ch) const+
−
{+
−
    const int script = QUnicodeTables::script(ch);+
−
    QFontEngine *engine;+
−
    if (d->capital == QFont::SmallCaps && ch.isLower())+
−
        engine = d->smallCapsFontPrivate()->engineForScript(script);+
−
    else+
−
        engine = d->engineForScript(script);+
−
    Q_ASSERT(engine != 0);+
−
+
−
    d->alterCharForCapitalization(ch);+
−
+
−
    QGlyphLayoutArray<10> glyphs;+
−
    int nglyphs = 9;+
−
    engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, 0);+
−
    glyph_metrics_t gm = engine->boundingBox(glyphs.glyphs[0]);+
−
    return QRectF(gm.x.toReal(), gm.y.toReal(), gm.width.toReal(), gm.height.toReal());+
−
}+
−
+
−
/*!+
−
    \overload+
−
+
−
    Returns the bounding rectangle of the characters in the given \a text.+
−
    This is the set of pixels the text would cover if drawn when constrained+
−
    to the bounding rectangle specified by \a rect.+
−
+
−
    The \a flags argument is the bitwise OR of the following flags:+
−
    \list+
−
    \o Qt::AlignLeft aligns to the left border, except for+
−
          Arabic and Hebrew where it aligns to the right.+
−
    \o Qt::AlignRight aligns to the right border, except for+
−
          Arabic and Hebrew where it aligns to the left.+
−
    \o Qt::AlignJustify produces justified text.+
−
    \o Qt::AlignHCenter aligns horizontally centered.+
−
    \o Qt::AlignTop aligns to the top border.+
−
    \o Qt::AlignBottom aligns to the bottom border.+
−
    \o Qt::AlignVCenter aligns vertically centered+
−
    \o Qt::AlignCenter (== \c{Qt::AlignHCenter | Qt::AlignVCenter})+
−
    \o Qt::TextSingleLine ignores newline characters in the text.+
−
    \o Qt::TextExpandTabs expands tabs (see below)+
−
    \o Qt::TextShowMnemonic interprets "&x" as \underline{x}; i.e., underlined.+
−
    \o Qt::TextWordWrap breaks the text to fit the rectangle.+
−
    \endlist+
−
+
−
    Qt::Horizontal alignment defaults to Qt::AlignLeft and vertical+
−
    alignment defaults to Qt::AlignTop.+
−
+
−
    If several of the horizontal or several of the vertical alignment+
−
    flags are set, the resulting alignment is undefined.+
−
+
−
    These flags are defined in \l{Qt::AlignmentFlag}.+
−
+
−
    If Qt::TextExpandTabs is set in \a flags, the following behavior is+
−
    used to interpret tab characters in the text:+
−
    \list+
−
    \o If \a tabArray is non-null, it specifies a 0-terminated sequence of+
−
       pixel-positions for tabs in the text.+
−
    \o If \a tabStops is non-zero, it is used as the tab spacing (in pixels).+
−
    \endlist+
−
+
−
    Note that the bounding rectangle may extend to the left of (0, 0),+
−
    e.g. for italicized fonts.+
−
+
−
    Newline characters are processed as line breaks.+
−
+
−
    Despite the different actual character heights, the heights of the+
−
    bounding rectangles of "Yes" and "yes" are the same.+
−
+
−
    The bounding rectangle returned by this function is somewhat larger+
−
    than that calculated by the simpler boundingRect() function. This+
−
    function uses the \link minLeftBearing() maximum left \endlink and+
−
    \link minRightBearing() right \endlink font bearings as is+
−
    necessary for multi-line text to align correctly. Also,+
−
    fontHeight() and lineSpacing() are used to calculate the height,+
−
    rather than individual character heights.+
−
+
−
    \sa width(), QPainter::boundingRect(), Qt::Alignment+
−
*/+
−
QRectF QFontMetricsF::boundingRect(const QRectF &rect, int flags, const QString& text,+
−
                                   int tabStops, int *tabArray) const+
−
{+
−
    int tabArrayLen = 0;+
−
    if (tabArray)+
−
        while (tabArray[tabArrayLen])+
−
            tabArrayLen++;+
−
+
−
    QRectF rb;+
−
    qt_format_text(QFont(d), rect, flags | Qt::TextDontPrint, text, &rb, tabStops, tabArray,+
−
                   tabArrayLen, 0);+
−
    return rb;+
−
}+
−
+
−
/*!+
−
    Returns the size in pixels of the characters in the given \a text.+
−
+
−
    The \a flags argument is the bitwise OR of the following flags:+
−
    \list+
−
    \o Qt::TextSingleLine ignores newline characters.+
−
    \o Qt::TextExpandTabs expands tabs (see below)+
−
    \o Qt::TextShowMnemonic interprets "&x" as \underline{x}; i.e., underlined.+
−
    \o Qt::TextWordBreak breaks the text to fit the rectangle.+
−
    \endlist+
−
+
−
    These flags are defined in \l{Qt::TextFlags}.+
−
+
−
    If Qt::TextExpandTabs is set in \a flags, the following behavior is+
−
    used to interpret tab characters in the text:+
−
    \list+
−
    \o If \a tabArray is non-null, it specifies a 0-terminated sequence of+
−
       pixel-positions for tabs in the text.+
−
    \o If \a tabStops is non-zero, it is used as the tab spacing (in pixels).+
−
    \endlist+
−
+
−
    Newline characters are processed as line breaks.+
−
+
−
    Note: Despite the different actual character heights, the heights of the+
−
    bounding rectangles of "Yes" and "yes" are the same.+
−
+
−
    \sa boundingRect()+
−
*/+
−
QSizeF QFontMetricsF::size(int flags, const QString &text, int tabStops, int *tabArray) const+
−
{+
−
    return boundingRect(QRectF(), flags, text, tabStops, tabArray).size();+
−
}+
−
+
−
/*!+
−
  \since 4.3+
−
+
−
    Returns a tight bounding rectangle around the characters in the+
−
    string specified by \a text. The bounding rectangle always covers+
−
    at least the set of pixels the text would cover if drawn at (0,+
−
    0).+
−
+
−
    Note that the bounding rectangle may extend to the left of (0, 0),+
−
    e.g. for italicized fonts, and that the width of the returned+
−
    rectangle might be different than what the width() method returns.+
−
+
−
    If you want to know the advance width of the string (to layout+
−
    a set of strings next to each other), use width() instead.+
−
+
−
    Newline characters are processed as normal characters, \e not as+
−
    linebreaks.+
−
+
−
    \warning Calling this method is very slow on Windows.+
−
+
−
    \sa width(), height(), boundingRect()+
−
*/+
−
QRectF QFontMetricsF::tightBoundingRect(const QString &text) const+
−
{+
−
    if (text.length() == 0)+
−
        return QRect();+
−
+
−
    QTextEngine layout(text, d);+
−
    layout.ignoreBidi = true;+
−
    layout.itemize();+
−
    glyph_metrics_t gm = layout.tightBoundingBox(0, text.length());+
−
    return QRectF(gm.x.toReal(), gm.y.toReal(), gm.width.toReal(), gm.height.toReal());+
−
}+
−
+
−
/*!+
−
    \since 4.2+
−
+
−
    If the string \a text is wider than \a width, returns an elided+
−
    version of the string (i.e., a string with "..." in it).+
−
    Otherwise, returns the original string.+
−
+
−
    The \a mode parameter specifies whether the text is elided on the+
−
    left (e.g., "...tech"), in the middle (e.g., "Tr...ch"), or on+
−
    the right (e.g., "Trol...").+
−
+
−
    The \a width is specified in pixels, not characters.+
−
+
−
    The \a flags argument is optional and currently only supports+
−
    Qt::TextShowMnemonic as value.+
−
*/+
−
QString QFontMetricsF::elidedText(const QString &text, Qt::TextElideMode mode, qreal width, int flags) const+
−
{+
−
    QStackTextEngine engine(text, QFont(d));+
−
    return engine.elidedText(mode, QFixed::fromReal(width), flags);+
−
}+
−
+
−
/*!+
−
    Returns the distance from the base line to where an underscore+
−
    should be drawn.+
−
+
−
    \sa overlinePos(), strikeOutPos(), lineWidth()+
−
*/+
−
qreal QFontMetricsF::underlinePos() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
    return engine->underlinePosition().toReal();+
−
}+
−
+
−
/*!+
−
    Returns the distance from the base line to where an overline+
−
    should be drawn.+
−
+
−
    \sa underlinePos(), strikeOutPos(), lineWidth()+
−
*/+
−
qreal QFontMetricsF::overlinePos() const+
−
{+
−
    return ascent() + 1;+
−
}+
−
+
−
/*!+
−
    Returns the distance from the base line to where the strikeout+
−
    line should be drawn.+
−
+
−
    \sa underlinePos(), overlinePos(), lineWidth()+
−
*/+
−
qreal QFontMetricsF::strikeOutPos() const+
−
{+
−
    return ascent() / 3.;+
−
}+
−
+
−
/*!+
−
    Returns the width of the underline and strikeout lines, adjusted+
−
    for the point size of the font.+
−
+
−
    \sa underlinePos(), overlinePos(), strikeOutPos()+
−
*/+
−
qreal QFontMetricsF::lineWidth() const+
−
{+
−
    QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);+
−
    Q_ASSERT(engine != 0);+
−
    return engine->lineThickness().toReal();+
−
}+
−
+
−
/*!+
−
    \fn QSize QFontMetrics::size(int flags, const QString &text, int len,+
−
                                 int tabStops, int *tabArray) const+
−
    \compat+
−
+
−
    Use the size() function in combination with QString::left()+
−
    instead.+
−
+
−
    \oldcode+
−
        QSize size = size(flags, str, len, tabstops, tabarray);+
−
    \newcode+
−
        QSize size = size(flags, str.left(len), tabstops, tabarray);+
−
    \endcode+
−
*/+
−
+
−
/*!+
−
    \fn QRect QFontMetrics::boundingRect(int x, int y, int w, int h, int flags,+
−
        const QString& text, int len, int tabStops, int *tabArray) const+
−
    \compat+
−
+
−
    Use the boundingRect() function in combination with+
−
    QString::left() and a QRect constructor instead.+
−
+
−
    \oldcode+
−
        QRect rect = boundingRect(x, y, w, h , flags, text, len,+
−
                                  tabStops, tabArray);+
−
    \newcode+
−
        QRect rect = boundingRect(QRect(x, y, w, h), flags, text.left(len),+
−
                                  tabstops, tabarray);+
−
    \endcode+
−
+
−
*/+
−
+
−
/*!+
−
    \fn QRect QFontMetrics::boundingRect(const QString &text, int len) const+
−
    \compat+
−
+
−
    Use the boundingRect() function in combination with+
−
    QString::left() instead.+
−
     +
−
    \oldcode+
−
        QRect rect = boundingRect(text, len);+
−
    \newcode+
−
        QRect rect = boundingRect(text.left(len));+
−
    \endcode+
−
*/+
−
+
−
QT_END_NAMESPACE+
−