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katie/src/gui/text/qfontmetrics.cpp
Ivailo Monev 0550dcd8d9 various cleanups 
Signed-off-by: Ivailo Monev <xakepa10@gmail.com>
2016-06-22 03:12:33 +00:00

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/****************************************************************************
**
** Copyright (C) 2015 The Qt Company Ltd.
** Contact: http://www.qt.io/licensing/
**
** This file is part of the QtGui module of the Qt Toolkit.
**
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****************************************************************************/
#include "qfont.h"
#include "qpaintdevice.h"
#include "qfontmetrics.h"
#include "qfont_p.h"
#include "qfontengine_p.h"
#include <qunicodetables_p.h>
#include <math.h>
#ifdef Q_WS_X11
#include "qx11info_x11.h"
#endif
QT_BEGIN_NAMESPACE
#ifdef Q_WS_X11
extern const QX11Info *qt_x11Info(const QPaintDevice *pd);
#endif
extern void qt_format_text(const QFont& font, const QRectF &_r,
int tf, const QString &text, QRectF *brect,
int tabStops, int *tabArray, int tabArrayLen,
QPainter *painter);
/*****************************************************************************
QFontMetrics member functions
*****************************************************************************/
/*!
\class QFontMetrics
\reentrant
\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.
\o QPainter::fontMetrics() returns the font metrics for a
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
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 0
\sa QFont, QFontInfo, QFontDatabase, QFontComboBox, {Character Map Example}
*/
/*!
\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())
{
}
/*!
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.
*/
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();
}
}
/*!
Constructs a copy of \a fm.
*/
QFontMetrics::QFontMetrics(const QFontMetrics &fm)
: d(fm.d.data())
{
}
/*!
Destroys the font metrics object and frees all allocated
resources.
*/
QFontMetrics::~QFontMetrics()
{
}
/*!
Assigns the font metrics \a fm.
*/
QFontMetrics &QFontMetrics::operator=(const QFontMetrics &fm)
{
d = fm.d.data();
return *this;
}
/*!
Returns true if \a other is equal to this object; 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 compatible.
\sa operator!=()
*/
bool QFontMetrics::operator ==(const QFontMetrics &other) const
{
return d == other.d;
}
/*!
\fn bool QFontMetrics::operator!=(const QFontMetrics &other)
Returns true if \a other is not equal to this object; 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 compatible.
\sa operator==()
*/
/*!
\fn bool QFontMetrics::operator !=(const QFontMetrics &other) const
Returns true if \a other is not equal to this object; 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 compatible.
\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()
*/
int QFontMetrics::ascent() const
{
QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);
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
characters extend to. 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()
*/
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()) + qRound(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()) + qRound(engine->ascent()) + qRound(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);
}
/*!
\fn bool QFontMetrics::inFontUcs4(uint character) const
\since 4.8
Returns true if the given \a character encoded in UCS-4/UTF-32 is a valid
character in the font; otherwise returns false.
*/
bool QFontMetrics::inFontUcs4(uint ucs4) const
{
const int script = QUnicodeTables::script(ucs4);
QFontEngine *engine = d->engineForScript(script);
Q_ASSERT(engine != 0);
if (engine->type() == QFontEngine::Box)
return false;
QString utf16 = QString::fromUcs4(&ucs4, 1);
return engine->canRender(utf16.data(), utf16.length());
}
/*!
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
qreal lb;
engine->getGlyphBearings(glyphs.glyphs[0], &lb);
return qRound(lb);
}
/*!
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
qreal rb;
engine->getGlyphBearings(glyphs.glyphs[0], 0, &rb);
return qRound(rb);
}
/*!
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
{
return width(text, len, 0);
}
/*!
\internal
*/
int QFontMetrics::width(const QString &text, int len, int flags) 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;
if (flags & Qt::TextBypassShaping) {
// Skip harfbuzz complex shaping, only use advances
int numGlyphs = len;
QVarLengthGlyphLayoutArray glyphs(numGlyphs);
QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);
if (!engine->stringToCMap(text.data(), len, &glyphs, &numGlyphs, 0)) {
glyphs.resize(numGlyphs);
if (!engine->stringToCMap(text.data(), len, &glyphs, &numGlyphs, 0))
Q_ASSERT_X(false, Q_FUNC_INFO, "stringToCMap shouldn't fail twice");
}
QFixed width;
for (int i = 0; i < numGlyphs; ++i)
width += glyphs.advances_x[i];
return qRound(width);
}
QStackTextEngine layout(text, d.data());
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);
QStackTextEngine layout(cstr, d.data());
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();
QStackTextEngine layout(text, d.data());
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.data()), 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();
QStackTextEngine layout(text, d.data());
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.data()));
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.data())
{
}
/*!
\since 4.2
Assigns \a other to this object.
*/
QFontMetricsF &QFontMetricsF::operator=(const QFontMetrics &other)
{
d = other.d.data();
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())
{
}
/*!
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();
}
}
/*!
Constructs a copy of \a fm.
*/
QFontMetricsF::QFontMetricsF(const QFontMetricsF &fm)
: d(fm.d.data())
{
}
/*!
Destroys the font metrics object and frees all allocated
resources.
*/
QFontMetricsF::~QFontMetricsF()
{
}
/*!
Assigns the font metrics \a fm to this font metrics object.
*/
QFontMetricsF &QFontMetricsF::operator=(const QFontMetricsF &fm)
{
d = fm.d.data();
return *this;
}
/*!
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;
}
/*!
\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);
}
/*!
\fn bool QFontMetricsF::inFontUcs4(uint ch) const
\since 4.8
Returns true if the character given by \a ch, encoded in UCS-4/UTF-32,
is a valid character in the font; otherwise returns false.
*/
bool QFontMetricsF::inFontUcs4(uint ucs4) const
{
const int script = QUnicodeTables::script(ucs4);
QFontEngine *engine = d->engineForScript(script);
Q_ASSERT(engine != 0);
if (engine->type() == QFontEngine::Box)
return false;
QString utf16 = QString::fromUcs4(&ucs4, 1);
return engine->canRender(utf16.data(), utf16.length());
}
/*!
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
qreal lb;
engine->getGlyphBearings(glyphs.glyphs[0], &lb);
return lb;
}
/*!
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
qreal rb;
engine->getGlyphBearings(glyphs.glyphs[0], 0, &rb);
return rb;
}
/*!
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
{
int pos = text.indexOf(QLatin1Char('\x9c'));
int len = (pos != -1) ? pos : text.length();
QStackTextEngine layout(text, d.data());
layout.ignoreBidi = true;
layout.itemize();
return layout.width(0, len).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();
QStackTextEngine layout(text, d.data());
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.data()), 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 | 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()
*/
QRectF QFontMetricsF::tightBoundingRect(const QString &text) const
{
if (text.length() == 0)
return QRect();
QStackTextEngine layout(text, d.data());
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
{
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.data()));
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
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