Struct qt_gui::QFontMetricsF

source · 
#[repr(C)]
pub struct QFontMetricsF { /* private fields */ }
Expand description

The QFontMetricsF class provides font metrics information.

C++ class: QFontMetricsF.

C++ documentation:

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 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:

QFont font(“times”, 24);
QFontMetricsF fm(font);
qreal pixelsWide = fm.width(“What’s the width of this text?”);
qreal pixelsHigh = fm.height();

Implementations§

source§

impl QFontMetricsF

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pub unsafe fn ascent(&self) -> c_double

Returns the ascent of the font.

Calls C++ function: double QFontMetricsF::ascent() const.

C++ documentation:

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.

See also descent().

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pub unsafe fn average_char_width(&self) -> c_double

Returns the average width of glyphs in the font.

Calls C++ function: double QFontMetricsF::averageCharWidth() const.

C++ documentation:

Returns the average width of glyphs in the font.

This function was introduced in Qt 4.2.

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pub unsafe fn bounding_rect_q_string( &self, string: impl CastInto<Ref<QString>> ) -> CppBox<QRectF>

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).

Calls C++ function: QRectF QFontMetricsF::boundingRect(const QString& string) const.

C++ documentation:

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 width() 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 width() 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 width(), height(), and QPainter::boundingRect().

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pub unsafe fn bounding_rect_q_char( &self, arg1: impl CastInto<Ref<QChar>> ) -> CppBox<QRectF>

Returns the bounding rectangle of the character ch relative to the left-most point on the base line.

Calls C++ function: QRectF QFontMetricsF::boundingRect(QChar arg1) const.

C++ documentation:

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 width().

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pub unsafe fn bounding_rect_q_rect_f_int_q_string_int_int( &self, r: impl CastInto<Ref<QRectF>>, flags: c_int, string: impl CastInto<Ref<QString>>, tabstops: c_int, tabarray: *mut c_int ) -> CppBox<QRectF>

This is an overloaded function.

Calls C++ function: QRectF QFontMetricsF::boundingRect(const QRectF& r, int flags, const QString& string, int tabstops = …, int* tabarray = …) const.

C++ documentation:

This is an overloaded function.

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.

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

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 Qt::AlignmentFlag.

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

  • 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).

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 maximum left and 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 width(), QPainter::boundingRect(), and Qt::Alignment.

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pub unsafe fn bounding_rect_q_rect_f_int_q_string_int( &self, r: impl CastInto<Ref<QRectF>>, flags: c_int, string: impl CastInto<Ref<QString>>, tabstops: c_int ) -> CppBox<QRectF>

This is an overloaded function.

Calls C++ function: QRectF QFontMetricsF::boundingRect(const QRectF& r, int flags, const QString& string, int tabstops = …) const.

C++ documentation:

This is an overloaded function.

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.

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

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 Qt::AlignmentFlag.

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

  • 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).

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 maximum left and 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 width(), QPainter::boundingRect(), and Qt::Alignment.

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pub unsafe fn bounding_rect_q_rect_f_int_q_string( &self, r: impl CastInto<Ref<QRectF>>, flags: c_int, string: impl CastInto<Ref<QString>> ) -> CppBox<QRectF>

This is an overloaded function.

Calls C++ function: QRectF QFontMetricsF::boundingRect(const QRectF& r, int flags, const QString& string) const.

C++ documentation:

This is an overloaded function.

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.

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

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 Qt::AlignmentFlag.

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

  • 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).

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 maximum left and 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 width(), QPainter::boundingRect(), and Qt::Alignment.

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pub unsafe fn cap_height(&self) -> c_double

Returns the cap height of the font.

Calls C++ function: double QFontMetricsF::capHeight() const.

C++ documentation:

Returns the cap height of the font.

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.

This function was introduced in Qt 5.8.

See also ascent().

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pub unsafe fn copy_from_q_font_metrics_f( &self, arg1: impl CastInto<Ref<QFontMetricsF>> ) -> Ref<QFontMetricsF>

Assigns the font metrics fm to this font metrics object.

Calls C++ function: QFontMetricsF& QFontMetricsF::operator=(const QFontMetricsF& arg1).

C++ documentation:

Assigns the font metrics fm to this font metrics object.

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pub unsafe fn copy_from_q_font_metrics( &self, arg1: impl CastInto<Ref<QFontMetrics>> ) -> Ref<QFontMetricsF>

Assigns other to this object.

Calls C++ function: QFontMetricsF& QFontMetricsF::operator=(const QFontMetrics& arg1).

C++ documentation:

Assigns other to this object.

This function was introduced in Qt 4.2.

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pub unsafe fn descent(&self) -> c_double

Returns the descent of the font.

Calls C++ function: double QFontMetricsF::descent() const.

C++ documentation:

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.

See also ascent().

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pub unsafe fn elided_text_4a( &self, text: impl CastInto<Ref<QString>>, mode: TextElideMode, width: c_double, flags: c_int ) -> CppBox<QString>

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.

Calls C++ function: QString QFontMetricsF::elidedText(const QString& text, Qt::TextElideMode mode, double width, int flags = …) const.

C++ documentation:

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 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.

This function was introduced in Qt 4.2.

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pub unsafe fn elided_text_3a( &self, text: impl CastInto<Ref<QString>>, mode: TextElideMode, width: c_double ) -> CppBox<QString>

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.

Calls C++ function: QString QFontMetricsF::elidedText(const QString& text, Qt::TextElideMode mode, double width) const.

C++ documentation:

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 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.

This function was introduced in Qt 4.2.

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pub unsafe fn font_dpi(&self) -> c_double

Available on cpp_lib_version="5.14.0" only.

Returns the font DPI.

Calls C++ function: double QFontMetricsF::fontDpi() const.

C++ documentation:

Returns the font DPI.

This function was introduced in Qt 5.14.

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pub unsafe fn height(&self) -> c_double

Returns the height of the font.

Calls C++ function: double QFontMetricsF::height() const.

C++ documentation:

Returns the height of the font.

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

See also leading() and lineSpacing().

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pub unsafe fn horizontal_advance_q_string_int( &self, string: impl CastInto<Ref<QString>>, length: c_int ) -> c_double

Available on cpp_lib_version="5.11.3" or cpp_lib_version="5.12.2" or cpp_lib_version="5.13.0" or cpp_lib_version="5.14.0" only.

Returns the horizontal advance in pixels of the first length characters of text. If length is negative (the default), the entire string is used.

Calls C++ function: double QFontMetricsF::horizontalAdvance(const QString& string, int length = …) const.

C++ documentation:

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

This function was introduced in Qt 5.11.

See also boundingRect().

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pub unsafe fn horizontal_advance_q_char( &self, arg1: impl CastInto<Ref<QChar>> ) -> c_double

Available on cpp_lib_version="5.11.3" or cpp_lib_version="5.12.2" or cpp_lib_version="5.13.0" or cpp_lib_version="5.14.0" only.

This is an overloaded function.

Calls C++ function: double QFontMetricsF::horizontalAdvance(QChar arg1) const.

C++ documentation:

This is an overloaded function.

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 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.

This function was introduced in Qt 5.11.

See also boundingRect().

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pub unsafe fn horizontal_advance_q_string( &self, string: impl CastInto<Ref<QString>> ) -> c_double

Available on cpp_lib_version="5.11.3" or cpp_lib_version="5.12.2" or cpp_lib_version="5.13.0" or cpp_lib_version="5.14.0" only.

Returns the horizontal advance in pixels of the first length characters of text. If length is negative (the default), the entire string is used.

Calls C++ function: double QFontMetricsF::horizontalAdvance(const QString& string) const.

C++ documentation:

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

This function was introduced in Qt 5.11.

See also boundingRect().

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pub unsafe fn in_font(&self, arg1: impl CastInto<Ref<QChar>>) -> bool

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

Calls C++ function: bool QFontMetricsF::inFont(QChar arg1) const.

C++ documentation:

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

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pub unsafe fn in_font_ucs4(&self, ucs4: c_uint) -> bool

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

Calls C++ function: bool QFontMetricsF::inFontUcs4(unsigned int ucs4) const.

C++ documentation:

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

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pub unsafe fn leading(&self) -> c_double

Returns the leading of the font.

Calls C++ function: double QFontMetricsF::leading() const.

C++ documentation:

Returns the leading of the font.

This is the natural inter-line spacing.

See also height() and lineSpacing().

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pub unsafe fn left_bearing(&self, arg1: impl CastInto<Ref<QChar>>) -> c_double

Returns the left bearing of character ch in the font.

Calls C++ function: double QFontMetricsF::leftBearing(QChar arg1) const.

C++ documentation:

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 width(QChar) for a graphical description of this metric.

See also rightBearing(), minLeftBearing(), and width().

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pub unsafe fn line_spacing(&self) -> c_double

Returns the distance from one base line to the next.

Calls C++ function: double QFontMetricsF::lineSpacing() const.

C++ documentation:

Returns the distance from one base line to the next.

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

See also height() and leading().

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pub unsafe fn line_width(&self) -> c_double

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

Calls C++ function: double QFontMetricsF::lineWidth() const.

C++ documentation:

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

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

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pub unsafe fn max_width(&self) -> c_double

Returns the width of the widest character in the font.

Calls C++ function: double QFontMetricsF::maxWidth() const.

C++ documentation:

Returns the width of the widest character in the font.

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pub unsafe fn min_left_bearing(&self) -> c_double

Returns the minimum left bearing of the font.

Calls C++ function: double QFontMetricsF::minLeftBearing() const.

C++ documentation:

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() and leftBearing().

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pub unsafe fn min_right_bearing(&self) -> c_double

Returns the minimum right bearing of the font.

Calls C++ function: double QFontMetricsF::minRightBearing() const.

C++ documentation:

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() and rightBearing().

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pub unsafe fn from_q_font( arg1: impl CastInto<Ref<QFont>> ) -> CppBox<QFontMetricsF>

Constructs a font metrics object for font.

Calls C++ function: [constructor] void QFontMetricsF::QFontMetricsF(const QFont& arg1).

C++ documentation:

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.

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pub unsafe fn from_q_font_q_paint_device( arg1: impl CastInto<Ref<QFont>>, pd: impl CastInto<Ptr<QPaintDevice>> ) -> CppBox<QFontMetricsF>

Constructs a font metrics object for font and paintdevice.

Calls C++ function: [constructor] void QFontMetricsF::QFontMetricsF(const QFont& arg1, QPaintDevice* pd).

C++ documentation:

Constructs a font metrics object for font and paintdevice.

The font metrics will be compatible with the paintdevice passed. If the paintdevice is 0, the metrics will be screen-compatible, ie. the metrics you get if you use the font for drawing text on a widgets or 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.

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pub unsafe fn from_q_font_metrics( arg1: impl CastInto<Ref<QFontMetrics>> ) -> CppBox<QFontMetricsF>

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

Calls C++ function: [constructor] void QFontMetricsF::QFontMetricsF(const QFontMetrics& arg1).

C++ documentation:

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

This function was introduced in Qt 4.2.

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pub unsafe fn new_copy( arg1: impl CastInto<Ref<QFontMetricsF>> ) -> CppBox<QFontMetricsF>

Constructs a copy of fm.

Calls C++ function: [constructor] void QFontMetricsF::QFontMetricsF(const QFontMetricsF& arg1).

C++ documentation:

Constructs a copy of fm.

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pub unsafe fn overline_pos(&self) -> c_double

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

Calls C++ function: double QFontMetricsF::overlinePos() const.

C++ documentation:

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

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

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pub unsafe fn right_bearing(&self, arg1: impl CastInto<Ref<QChar>>) -> c_double

Returns the right bearing of character ch in the font.

Calls C++ function: double QFontMetricsF::rightBearing(QChar arg1) const.

C++ documentation:

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 width() of the character.

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

See also leftBearing(), minRightBearing(), and width().

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pub unsafe fn size_4a( &self, flags: c_int, str: impl CastInto<Ref<QString>>, tabstops: c_int, tabarray: *mut c_int ) -> CppBox<QSizeF>

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

Calls C++ function: QSizeF QFontMetricsF::size(int flags, const QString& str, int tabstops = …, int* tabarray = …) const.

C++ documentation:

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

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

These flags are defined in the Qt::TextFlag enum.

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

  • 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).

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().

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pub unsafe fn size_3a( &self, flags: c_int, str: impl CastInto<Ref<QString>>, tabstops: c_int ) -> CppBox<QSizeF>

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

Calls C++ function: QSizeF QFontMetricsF::size(int flags, const QString& str, int tabstops = …) const.

C++ documentation:

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

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

These flags are defined in the Qt::TextFlag enum.

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

  • 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).

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().

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pub unsafe fn size_2a( &self, flags: c_int, str: impl CastInto<Ref<QString>> ) -> CppBox<QSizeF>

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

Calls C++ function: QSizeF QFontMetricsF::size(int flags, const QString& str) const.

C++ documentation:

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

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

These flags are defined in the Qt::TextFlag enum.

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

  • 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).

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().

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pub unsafe fn strike_out_pos(&self) -> c_double

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

Calls C++ function: double QFontMetricsF::strikeOutPos() const.

C++ documentation:

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

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

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pub unsafe fn swap(&self, other: impl CastInto<Ref<QFontMetricsF>>)

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

Calls C++ function: void QFontMetricsF::swap(QFontMetricsF& other).

C++ documentation:

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

This function was introduced in Qt 5.0.

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pub unsafe fn tight_bounding_rect( &self, text: impl CastInto<Ref<QString>> ) -> CppBox<QRectF>

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).

Calls C++ function: QRectF QFontMetricsF::tightBoundingRect(const QString& text) const.

C++ documentation:

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 width() 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 width() instead.

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

Warning: Calling this method is very slow on Windows.

This function was introduced in Qt 4.3.

See also width(), height(), and boundingRect().

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pub unsafe fn underline_pos(&self) -> c_double

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

Calls C++ function: double QFontMetricsF::underlinePos() const.

C++ documentation:

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

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

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pub unsafe fn width_q_string( &self, string: impl CastInto<Ref<QString>> ) -> c_double

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

Calls C++ function: double QFontMetricsF::width(const QString& string) const.

C++ documentation:

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

Note that this value is 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.

See also boundingRect().

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pub unsafe fn width_q_char(&self, arg1: impl CastInto<Ref<QChar>>) -> c_double

This is an overloaded function.

Calls C++ function: double QFontMetricsF::width(QChar arg1) const.

C++ documentation:

This is an overloaded function.

Bearings

Returns the logical width 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 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.

See also boundingRect().

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pub unsafe fn x_height(&self) -> c_double

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

Calls C++ function: double QFontMetricsF::xHeight() const.

C++ documentation:

Returns the ‘x’ height of the font. This is often but not always the same as the height of the character ‘x’.

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impl CppDeletable for QFontMetricsF

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unsafe fn delete(&self)

Destroys the font metrics object and frees all allocated resources.

Calls C++ function: [destructor] void QFontMetricsF::~QFontMetricsF().

C++ documentation:

Destroys the font metrics object and frees all allocated resources.

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impl PartialEq<Ref<QFontMetricsF>> for QFontMetricsF

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fn eq(&self, other: &Ref<QFontMetricsF>) -> bool

Returns true if the font metrics are equal to the other font metrics; otherwise returns false.

Calls C++ function: bool QFontMetricsF::operator==(const QFontMetricsF& other) const.

C++ documentation:

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.

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fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

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fn borrow_mut(&mut self) -> &mut T

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unsafe fn cast_into(self) -> U

Performs the conversion. Read more
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Returns the argument unchanged.

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fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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Convert type of a const pointer. Read more
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where U: TryFrom<T>,

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type Error = <U as TryFrom<T>>::Error

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Performs the conversion.