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Internal/Contributor docs for the Qt SDK. <b>Note:</b> These are NOT official API docs; those are found <a href='https://doc.qt.io/'>here</a>.
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QFontMetricsF Class Reference

\reentrant \inmodule QtGui More...

#include <qfontmetrics.h>

+ Collaboration diagram for QFontMetricsF:

Public Member Functions

 QFontMetricsF (const QFont &font)
 Constructs a font metrics object for font.
 
 QFontMetricsF (const QFont &font, const QPaintDevice *pd)
 
 QFontMetricsF (const QFontMetrics &)
 
 QFontMetricsF (const QFontMetricsF &)
 Constructs a copy of fm.
 
 ~QFontMetricsF ()
 Destroys the font metrics object and frees all allocated resources.
 
QFontMetricsFoperator= (const QFontMetricsF &)
 Assigns the font metrics fm to this font metrics object.
 
QFontMetricsFoperator= (const QFontMetrics &)
 
void swap (QFontMetricsF &other) noexcept
 
qreal ascent () const
 Returns the ascent of the font.
 
qreal capHeight () const
 Returns the cap height of the font.
 
qreal descent () const
 Returns the descent of the font.
 
qreal height () const
 Returns the height of the font.
 
qreal leading () const
 Returns the leading of the font.
 
qreal lineSpacing () const
 Returns the distance from one base line to the next.
 
qreal minLeftBearing () const
 Returns the minimum left bearing of the font.
 
qreal minRightBearing () const
 Returns the minimum right bearing of the font.
 
qreal maxWidth () const
 Returns the width of the widest character in the font.
 
qreal xHeight () const
 Returns the 'x' height of the font.
 
qreal averageCharWidth () const
 
bool inFont (QChar) const
 Returns true if character ch is a valid character in the font; otherwise returns false.
 
bool inFontUcs4 (uint ucs4) const
 Returns true if the character given by ch, encoded in UCS-4/UTF-32, is a valid character in the font; otherwise returns false.
 
qreal leftBearing (QChar) const
 Returns the left bearing of character ch in the font.
 
qreal rightBearing (QChar) const
 Returns the right bearing of character ch in the font.
 
qreal horizontalAdvance (const QString &string, int length=-1) const
 Returns the horizontal advance in pixels of the first length characters of text.
 
qreal horizontalAdvance (QChar) const
 This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
 
qreal horizontalAdvance (const QString &string, const QTextOption &textOption) const
 Returns the horizontal advance in pixels of text laid out using option.
 
QRectF boundingRect (const QString &string) const
 Returns the bounding rectangle of the characters in the string specified by text.
 
QRectF boundingRect (const QString &text, const QTextOption &textOption) const
 Returns the bounding rectangle of the characters in the string specified by text laid out using option.
 
QRectF boundingRect (QChar) const
 Returns the bounding rectangle of the character ch relative to the left-most point on the base line.
 
QRectF boundingRect (const QRectF &r, int flags, const QString &string, int tabstops=0, int *tabarray=nullptr) const
 This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Returns the bounding rectangle of the characters in the given text.
 
QSizeF size (int flags, const QString &str, int tabstops=0, int *tabarray=nullptr) const
 Returns the size in pixels of the characters in the given text.
 
QRectF tightBoundingRect (const QString &text) const
 
QRectF tightBoundingRect (const QString &text, const QTextOption &textOption) const
 Returns a tight bounding rectangle around the characters in the string specified by text laid out using option.
 
QString elidedText (const QString &text, Qt::TextElideMode mode, qreal width, int flags=0) const
 
qreal underlinePos () const
 Returns the distance from the base line to where an underscore should be drawn.
 
qreal overlinePos () const
 Returns the distance from the base line to where an overline should be drawn.
 
qreal strikeOutPos () const
 Returns the distance from the base line to where the strikeout line should be drawn.
 
qreal lineWidth () const
 Returns the width of the underline and strikeout lines, adjusted for the point size of the font.
 
qreal fontDpi () const
 
bool operator== (const QFontMetricsF &other) const
 Returns true if the font metrics are equal to the other font metrics; otherwise returns false.
 
bool operator!= (const QFontMetricsF &other) const
 This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Returns true if the font metrics are not equal to the other font metrics; otherwise returns false.
 

Detailed Description

\reentrant \inmodule QtGui

The QFontMetricsF class provides font metrics information.

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 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 horizontalAdvance(), 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 horizontalAdvance(), 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:

QFont font("times", 24);
qreal pixelsWide = fm.horizontalAdvance("What's the advance width of this text?");
qreal pixelsHigh = fm.height();
See also
QFont, QFontInfo, QFontDatabase

Definition at line 91 of file qfontmetrics.h.

Constructor & Destructor Documentation

◆ QFontMetricsF() [1/4]

QFontMetricsF::QFontMetricsF ( const QFont & font)
explicit

Constructs a font metrics object for font.

The font metrics will be compatible with the paintdevice used to create 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.

Definition at line 1061 of file qfontmetrics.cpp.

◆ QFontMetricsF() [2/4]

QFontMetricsF::QFontMetricsF ( const QFont & font,
const QPaintDevice * paintdevice )
Since
5.13 Constructs a font metrics object for font and paintdevice.

The font metrics will be compatible with the paintdevice passed. If the paintdevice is \nullptr, the metrics will be screen-compatible, ie. the metrics you get if you use the font for drawing text on a \l{QWidget}{widgets} or \l{QPixmap}{pixmaps}, 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.

Definition at line 1081 of file qfontmetrics.cpp.

References QFontPrivate::dpi, font, and qt_defaultDpi().

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◆ QFontMetricsF() [3/4]

QFontMetricsF::QFontMetricsF ( const QFontMetrics & fontMetrics)
Since
4.2

Constructs a font metrics object with floating point precision from the given fontMetrics object.

Definition at line 1022 of file qfontmetrics.cpp.

◆ QFontMetricsF() [4/4]

QFontMetricsF::QFontMetricsF ( const QFontMetricsF & fm)

Constructs a copy of fm.

Definition at line 1096 of file qfontmetrics.cpp.

◆ ~QFontMetricsF()

QFontMetricsF::~QFontMetricsF ( )

Destroys the font metrics object and frees all allocated resources.

Definition at line 1105 of file qfontmetrics.cpp.

Member Function Documentation

◆ ascent()

qreal QFontMetricsF::ascent ( ) const

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 a certain character, so it is possible (though rare) that this value will be too small.

See also
descent()

Definition at line 1152 of file qfontmetrics.cpp.

References engine, QFontPrivate::engineForScript(), and Q_ASSERT.

Referenced by QQuickFontMetrics::ascent(), overlinePos(), strikeOutPos(), QQuickTextPrivate::updateSize(), and QSvgVisitorImpl::visitTextNode().

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◆ averageCharWidth()

qreal QFontMetricsF::averageCharWidth ( ) const
Since
4.2

Returns the average width of glyphs in the font.

Definition at line 1301 of file qfontmetrics.cpp.

References engine, QFontPrivate::engineForScript(), and Q_ASSERT.

Referenced by QQuickFontMetrics::averageCharacterWidth().

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◆ boundingRect() [1/4]

QRectF QFontMetricsF::boundingRect ( const QRectF & rect,
int flags,
const QString & text,
int tabStops = 0,
int * tabArray = nullptr ) const

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Returns the bounding rectangle of the characters in the given text.

This is the set of pixels the text would cover if drawn when constrained to the bounding rectangle specified by rect. If rect is a reference to a \nullptr object, e.g. when passing a default constructed QRectF, the bounding rectangle will not constrain itself to the size.

The flags argument is the bitwise OR of the following flags: \list

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 flags, the following behavior is used to interpret tab characters in the text: \list

  • If tabArray is non-null, it specifies a 0-terminated sequence of pixel-positions for tabs in the text.
  • If 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 \l{minLeftBearing()}{maximum left} and \l{minRightBearing()}{right} 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.

See also
horizontalAdvance(), QPainter::boundingRect(), Qt::Alignment

Definition at line 1674 of file qfontmetrics.cpp.

References QExplicitlySharedDataPointer< T >::data(), qt_format_text(), rect, text, and Qt::TextDontPrint.

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◆ boundingRect() [2/4]

QRectF QFontMetricsF::boundingRect ( const QString & text) const

Returns the bounding rectangle of the characters in the string specified by 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 horizontalAdvance() method returns.

If you want to know the advance width of the string (to lay out a set of strings next to each other), use horizontalAdvance() instead.

Newline characters are processed as normal characters, not as linebreaks.

The height of the bounding rectangle is at least as large as the value returned height().

See also
horizontalAdvance(), height(), QPainter::boundingRect()

Definition at line 1533 of file qfontmetrics.cpp.

References QExplicitlySharedDataPointer< T >::data(), layout, QString::size(), and text.

Referenced by QQuickTextMetrics::boundingRect(), QQuickFontMetrics::boundingRect(), and size().

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◆ boundingRect() [3/4]

QRectF QFontMetricsF::boundingRect ( const QString & text,
const QTextOption & option ) const

Returns the bounding rectangle of the characters in the string specified by text laid out using option.

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 horizontalAdvance() method returns.

If you want to know the advance width of the string (to lay out a set of strings next to each other), use horizontalAdvance() instead.

Newline characters are processed as normal characters, not as linebreaks.

The height of the bounding rectangle is at least as large as the value returned height().

Since
6.3
See also
horizontalAdvance(), height(), QPainter::boundingRect()

Definition at line 1568 of file qfontmetrics.cpp.

References QExplicitlySharedDataPointer< T >::data(), layout, QString::size(), and text.

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◆ boundingRect() [4/4]

QRectF QFontMetricsF::boundingRect ( QChar ch) const

Returns the bounding rectangle of the character 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 all pixels in the bounding rectangle.

Note that the rectangle usually extends both above and below the base line.

See also
horizontalAdvance()

Definition at line 1595 of file qfontmetrics.cpp.

References QFontPrivate::alterCharForCapitalization(), QFontPrivate::capital, ch, engine, QFontPrivate::engineForScript(), Q_ASSERT, QFont::SmallCaps, and QFontPrivate::smallCapsFontPrivate().

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◆ capHeight()

qreal QFontMetricsF::capHeight ( ) const

Returns the cap height of the font.

Since
5.8

The cap height of a font is the height of a capital letter above the baseline. It specifically is the height of capital letters that are flat - such as H or I - as opposed to round letters such as O, or pointed letters like A, both of which may display overshoot.

See also
ascent()

Definition at line 1171 of file qfontmetrics.cpp.

References engine, QFontPrivate::engineForScript(), and Q_ASSERT.

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◆ descent()

qreal QFontMetricsF::descent ( ) const

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 a certain character, so it is possible (though rare) that this value will be too small.

See also
ascent()

Definition at line 1189 of file qfontmetrics.cpp.

References engine, QFontPrivate::engineForScript(), and Q_ASSERT.

Referenced by QQuickFontMetrics::descent().

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◆ elidedText()

QString QFontMetricsF::elidedText ( const QString & text,
Qt::TextElideMode mode,
qreal width,
int flags = 0 ) const
Since
4.2

If the string text is wider than width, returns an elided version of the string (i.e., a string with "..." in it). Otherwise, returns the original string.

The mode parameter specifies whether the text is elided on the left (for example, "...tech"), in the middle (for example, "Tr...ch"), or on the right (for example, "Trol...").

The width is specified in pixels, not characters.

The flags argument is optional and currently only supports Qt::TextShowMnemonic as value.

The elide mark follows the \l{Qt::LayoutDirection}{layoutdirection}. For example, it will be on the right side of the text for right-to-left layouts if the mode is {Qt::ElideLeft}, and on the left side of the text if the mode is {Qt::ElideRight}.

Definition at line 1807 of file qfontmetrics.cpp.

References QExplicitlySharedDataPointer< T >::data(), engine, QFixed::fromReal(), QString::indexOf(), QString::mid(), s_variableLengthStringSeparator(), text, and Qt::TextLongestVariant.

Referenced by QQuickTextMetrics::elidedText(), and QQuickFontMetrics::elidedText().

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◆ fontDpi()

qreal QFontMetricsF::fontDpi ( ) const
Since
5.14

Returns the font DPI.

Definition at line 1879 of file qfontmetrics.cpp.

References QFontPrivate::dpi.

◆ height()

qreal QFontMetricsF::height ( ) const

Returns the height of the font.

This is always equal to ascent()+descent().

See also
leading(), lineSpacing()

Definition at line 1203 of file qfontmetrics.cpp.

References engine, QFontPrivate::engineForScript(), and Q_ASSERT.

Referenced by QQuickFontMetrics::height(), and QComboBoxPrivate::recomputeSizeHint().

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◆ horizontalAdvance() [1/3]

qreal QFontMetricsF::horizontalAdvance ( const QString & text,
const QTextOption & option ) const

Returns the horizontal advance in pixels of text laid out using option.

The advance is the distance appropriate for drawing a subsequent character after text.

Since
6.3
See also
boundingRect()

Definition at line 1441 of file qfontmetrics.cpp.

References QExplicitlySharedDataPointer< T >::data(), QString::indexOf(), layout, pos, s_variableLengthStringSeparator(), QString::size(), and text.

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◆ horizontalAdvance() [2/3]

qreal QFontMetricsF::horizontalAdvance ( const QString & text,
int length = -1 ) const

Returns the horizontal advance in pixels of the first length characters of text.

If length is negative (the default), the entire string is used. The entire length of text is analysed even if length is substantially shorter.

The advance is the distance appropriate for drawing a subsequent character after text.

Since
5.11
See also
boundingRect()

Definition at line 1413 of file qfontmetrics.cpp.

References QExplicitlySharedDataPointer< T >::data(), QString::indexOf(), layout, QStringView::left(), pos, s_variableLengthStringSeparator(), QString::size(), and text.

Referenced by QQuickTextMetrics::advanceWidth(), and QQuickFontMetrics::advanceWidth().

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◆ horizontalAdvance() [3/3]

qreal QFontMetricsF::horizontalAdvance ( QChar ch) const

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Bearings

Returns the horizontal advance of character ch in pixels. This is a distance appropriate for drawing a subsequent character after ch.

Some of the metrics are described in the image to the right. The central dark rectangles cover the logical horizontalAdvance() 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.
Since
5.11
See also
boundingRect()

Definition at line 1485 of file qfontmetrics.cpp.

References QGlyphLayout::advances, QFontPrivate::alterCharForCapitalization(), QFontPrivate::capital, ch, engine, QFontPrivate::engineForScript(), QGlyphLayout::glyphs, QGlyphLayout::numGlyphs, Q_ASSERT, QFont::SmallCaps, QFontPrivate::smallCapsFontPrivate(), and QFixed::toReal().

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◆ inFont()

bool QFontMetricsF::inFont ( QChar ch) const

Returns true if character ch is a valid character in the font; otherwise returns false.

Definition at line 1312 of file qfontmetrics.cpp.

References ch, and inFontUcs4().

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◆ inFontUcs4()

bool QFontMetricsF::inFontUcs4 ( uint ucs4) const

Returns true if the character given by ch, encoded in UCS-4/UTF-32, is a valid character in the font; otherwise returns false.

Definition at line 1323 of file qfontmetrics.cpp.

References QFontEngine::Box, engine, QFontPrivate::engineForScript(), and Q_ASSERT.

Referenced by inFont().

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◆ leading()

qreal QFontMetricsF::leading ( ) const

Returns the leading of the font.

This is the natural inter-line spacing.

See also
height(), lineSpacing()

Definition at line 1218 of file qfontmetrics.cpp.

References engine, QFontPrivate::engineForScript(), and Q_ASSERT.

Referenced by QQuickFontMetrics::leading().

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◆ leftBearing()

qreal QFontMetricsF::leftBearing ( QChar ch) const

Returns the left bearing of character 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 horizontalAdvance() for a graphical description of this metric.

See also
rightBearing(), minLeftBearing(), horizontalAdvance()

Definition at line 1345 of file qfontmetrics.cpp.

References QFontPrivate::alterCharForCapitalization(), QFontEngine::Box, QFontPrivate::capital, ch, engine, QFontPrivate::engineForScript(), Q_ASSERT, QFont::SmallCaps, and QFontPrivate::smallCapsFontPrivate().

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◆ lineSpacing()

qreal QFontMetricsF::lineSpacing ( ) const

Returns the distance from one base line to the next.

This value is always equal to leading()+height().

See also
height(), leading()

Definition at line 1232 of file qfontmetrics.cpp.

References engine, QFontPrivate::engineForScript(), and Q_ASSERT.

Referenced by QQuickFontMetrics::lineSpacing().

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◆ lineWidth()

qreal QFontMetricsF::lineWidth ( ) const

Returns the width of the underline and strikeout lines, adjusted for the point size of the font.

See also
underlinePos(), overlinePos(), strikeOutPos()

Definition at line 1867 of file qfontmetrics.cpp.

References engine, QFontPrivate::engineForScript(), and Q_ASSERT.

Referenced by QQuickFontMetrics::lineWidth().

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◆ maxWidth()

qreal QFontMetricsF::maxWidth ( ) const

Returns the width of the widest character in the font.

Definition at line 1276 of file qfontmetrics.cpp.

References engine, QFontPrivate::engineForScript(), and Q_ASSERT.

Referenced by QQuickFontMetrics::maximumCharacterWidth().

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◆ minLeftBearing()

qreal QFontMetricsF::minLeftBearing ( ) const

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.

See also
minRightBearing(), leftBearing()

Definition at line 1249 of file qfontmetrics.cpp.

References engine, QFontPrivate::engineForScript(), and Q_ASSERT.

Referenced by QQuickFontMetrics::minimumLeftBearing().

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◆ minRightBearing()

qreal QFontMetricsF::minRightBearing ( ) const

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.

See also
minLeftBearing(), rightBearing()

Definition at line 1266 of file qfontmetrics.cpp.

References engine, QFontPrivate::engineForScript(), and Q_ASSERT.

Referenced by QQuickFontMetrics::minimumRightBearing().

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◆ operator!=()

bool QFontMetricsF::operator!= ( const QFontMetricsF & other) const
inline

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Returns true if the font metrics are not equal to the other font metrics; otherwise returns false.

See also
operator==()

Definition at line 148 of file qfontmetrics.h.

References operator==(), and other().

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◆ operator=() [1/2]

QFontMetricsF & QFontMetricsF::operator= ( const QFontMetrics & other)
Since
4.2

Assigns other to this object.

Definition at line 1032 of file qfontmetrics.cpp.

References other().

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◆ operator=() [2/2]

QFontMetricsF & QFontMetricsF::operator= ( const QFontMetricsF & fm)

Assigns the font metrics fm to this font metrics object.

Definition at line 1112 of file qfontmetrics.cpp.

◆ operator==()

bool QFontMetricsF::operator== ( const QFontMetricsF & other) const

Returns true if the font metrics are equal to the 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.

Definition at line 1126 of file qfontmetrics.cpp.

References other().

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◆ overlinePos()

qreal QFontMetricsF::overlinePos ( ) const

Returns the distance from the base line to where an overline should be drawn.

See also
underlinePos(), strikeOutPos(), lineWidth()

Definition at line 1845 of file qfontmetrics.cpp.

References ascent().

Referenced by QQuickFontMetrics::overlinePosition().

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◆ rightBearing()

qreal QFontMetricsF::rightBearing ( QChar ch) const

Returns the right bearing of character 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 horizontalAdvance() of the character.

See horizontalAdvance() for a graphical description of this metric.

See also
leftBearing(), minRightBearing(), horizontalAdvance()

Definition at line 1378 of file qfontmetrics.cpp.

References QFontPrivate::alterCharForCapitalization(), QFontEngine::Box, QFontPrivate::capital, ch, engine, QFontPrivate::engineForScript(), Q_ASSERT, QFont::SmallCaps, and QFontPrivate::smallCapsFontPrivate().

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◆ size()

QSizeF QFontMetricsF::size ( int flags,
const QString & text,
int tabStops = 0,
int * tabArray = nullptr ) const

Returns the size in pixels of the characters in the given text.

The flags argument is the bitwise OR of the following flags: \list

These flags are defined in the \l{Qt::TextFlag} enum.

If Qt::TextExpandTabs is set in flags, the following behavior is used to interpret tab characters in the text: \list

  • If tabArray is non-null, it specifies a 0-terminated sequence of pixel-positions for tabs in the text.
  • If 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.

See also
boundingRect()

Definition at line 1716 of file qfontmetrics.cpp.

References boundingRect(), QRectF::size(), text, and Qt::TextLongestVariant.

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◆ strikeOutPos()

qreal QFontMetricsF::strikeOutPos ( ) const

Returns the distance from the base line to where the strikeout line should be drawn.

See also
underlinePos(), overlinePos(), lineWidth()

Definition at line 1856 of file qfontmetrics.cpp.

References ascent().

Referenced by QQuickFontMetrics::strikeOutPosition().

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◆ swap()

void QFontMetricsF::swap ( QFontMetricsF & other)
inlinenoexcept
Since
5.0

Swaps this font metrics instance with other. This function is very fast and never fails.

Definition at line 104 of file qfontmetrics.h.

References d, and other().

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◆ tightBoundingRect() [1/2]

QRectF QFontMetricsF::tightBoundingRect ( const QString & text) const
Since
4.3

Returns a tight bounding rectangle around the characters in the string specified by 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 horizontalAdvance() method returns.

If you want to know the advance width of the string (to lay out a set of strings next to each other), use horizontalAdvance() instead.

Newline characters are processed as normal characters, not as linebreaks.

See also
horizontalAdvance(), height(), boundingRect()

Definition at line 1742 of file qfontmetrics.cpp.

References QExplicitlySharedDataPointer< T >::data(), layout, QString::size(), and text.

Referenced by QQuickTextMetrics::tightBoundingRect(), and QQuickFontMetrics::tightBoundingRect().

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◆ tightBoundingRect() [2/2]

QRectF QFontMetricsF::tightBoundingRect ( const QString & text,
const QTextOption & option ) const

Returns a tight bounding rectangle around the characters in the string specified by text laid out using option.

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 horizontalAdvance() method returns.

If you want to know the advance width of the string (to lay out a set of strings next to each other), use horizontalAdvance() instead.

Newline characters are processed as normal characters, not as linebreaks.

Since
6.3
See also
horizontalAdvance(), height(), boundingRect()

Definition at line 1774 of file qfontmetrics.cpp.

References QExplicitlySharedDataPointer< T >::data(), layout, QString::size(), and text.

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◆ underlinePos()

qreal QFontMetricsF::underlinePos ( ) const

Returns the distance from the base line to where an underscore should be drawn.

See also
overlinePos(), strikeOutPos(), lineWidth()

Definition at line 1832 of file qfontmetrics.cpp.

References engine, QFontPrivate::engineForScript(), and Q_ASSERT.

Referenced by QQuickFontMetrics::underlinePosition().

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◆ xHeight()

qreal QFontMetricsF::xHeight ( ) const

Returns the 'x' height of the font.

This is often but not always the same as the height of the character 'x'.

Definition at line 1287 of file qfontmetrics.cpp.

References QFontEngine::ascent(), QFontPrivate::capital, engine, QFontPrivate::engineForScript(), Q_ASSERT, QFont::SmallCaps, and QFontPrivate::smallCapsFontPrivate().

Referenced by QQuickFontMetrics::xHeight().

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The documentation for this class was generated from the following files: