Provides access to a single physical instance of a given font. More...

Public Types
enum	AntialiasingType

Public Methods
	QRawFont ()

	QRawFont (const QByteArray &fontData, qreal pixelSize, QFont::HintingPreference hintingPreference=QFont::PreferDefaultHinting)

	QRawFont (const QRawFont &other)

	QRawFont (const QString &fileName, qreal pixelSize, QFont::HintingPreference hintingPreference=QFont::PreferDefaultHinting)

	~QRawFont ()

bool	advancesForGlyphIndexes (const quint32 glyphIndexes, QPointF advances, int numGlyphs) const

bool	advancesForGlyphIndexes (const quint32 glyphIndexes, QPointF advances, int numGlyphs, LayoutFlags layoutFlags) const

QVector< QPointF >	advancesForGlyphIndexes (const QVector< quint32 > &glyphIndexes) const

QVector< QPointF >	advancesForGlyphIndexes (const QVector< quint32 > &glyphIndexes, LayoutFlags layoutFlags) const

QImage	alphaMapForGlyph (quint32 glyphIndex, AntialiasingType antialiasingType=SubPixelAntialiasing, const QTransform &transform=QTransform ()) const

qreal	ascent () const

qreal	averageCharWidth () const

QRectF	boundingRect (quint32 glyphIndex) const

qreal	descent () const

QString	familyName () const

QByteArray	fontTable (const char *tagName) const

bool	glyphIndexesForChars (QStringView str, quint32 glyphIndexes, int numGlyphs) const

QVector< quint32 >	glyphIndexesForString (const QString &text) const

QFont::HintingPreference	hintingPreference () const

bool	isValid () const

qreal	leading () const

qreal	lineThickness () const

void	loadFromData (const QByteArray &fontData, qreal pixelSize, QFont::HintingPreference hintingPreference)

void	loadFromFile (const QString &fileName, qreal pixelSize, QFont::HintingPreference hintingPreference)

qreal	maxCharWidth () const

bool	operator!= (const QRawFont &other) const

QRawFont &	operator= (const QRawFont &other)

QRawFont &	operator= (QRawFont &&other)

bool	operator== (const QRawFont &other) const

QPainterPath	pathForGlyph (quint32 glyphIndex) const

qreal	pixelSize () const

void	setPixelSize (qreal pixelSize)

QFont::Style	style () const

QString	styleName () const

QList< QFontDatabase::WritingSystem >	supportedWritingSystems () const

bool	supportsCharacter (QChar character) const

bool	supportsCharacter (quint32 ucs4) const

void	swap (QRawFont &other)

qreal	underlinePosition () const

qreal	unitsPerEm () const

int	weight () const

qreal	xHeight () const

Static Public Methods
static QRawFont	fromFont (const QFont &font, QFontDatabase::WritingSystem writingSystem=QFontDatabase::Any)

Friends
class	QTextLayout

Detailed Description

The QRawFont class provides access to a single specific font using an existing font file. The font family, point size, and font style are all required when specifying a QRawFont. An example would be "Helvetica 14 Bold". This is a low level class and for most use cased using the QFont class will be a better choice.

When using the QFont class to display text the rendering system will attempt to find each character in the specified font. If there is no match a different font may be used. This happens on a character by character basis. This may not produce the desired result. If your application needs to select a specific font then using QRawFont will be necessary.

This class can be used in combination with the QGlyphRun class to draw specific glyph indexes at specific positions.

Constructiong a QRawFont

A QRawFont object can be constructed in one of the following ways. The object belongs to the thread where it was constructed and can not be moved to a different thread.

Calling QTextLayout::glyphs() or QTextFragment::glyphs(). The returned QGlyphs objects will contain QRawFont objects which represent the actual fonts used to render each portion of the text.
Passing a QFont object to QRawFont::fromFont(). The function will return a QRawFont object representing the font that will be selected as response to the QFont query and the selected writing system.
Passing a file name or QByteArray directly to the QRawFont constructor, or by calling loadFromFile() or loadFromData(). In this case, the font will not be registered in QFontDatabase, and it will not be available as part of regular font selection.

See also: QTextLine::horizontalAdvance(), QFontMetricsF::width()

Member Enumeration Documentation

enum QRawFont::AntialiasingType

This enum represents the different ways a glyph can be rasterized in the function alphaMapForGlyph().

Constant	Value	Description
`QRawFont::PixelAntialiasing`	`0`	Will rasterize by measuring the coverage of the shape on whole pixels. The returned image contains the alpha values of each pixel based on the coverage of the glyph shape.
`QRawFont::SubPixelAntialiasing`	`1`	Will rasterize by measuring the coverage of each subpixel, returning a separate alpha value for each of the red, green and blue components of each pixel.

Constructor & Destructor Documentation

QRawFont::QRawFont ( )

Constructs an invalid QRawFont.

QRawFont::QRawFont	(	const QString &	fileName,
		qreal	pixelSize,
		QFont::HintingPreference	hintingPreference = `QFont::PreferDefaultHinting`
	)

Constructs a QRawFont representing the font contained in the file referenced by fileName for the size (in pixels) given by pixelSize, and using the hinting preference specified by hintingPreference.

Note: The referenced file must contain a TrueType or OpenType font.

QRawFont::QRawFont	(	const QByteArray &	fontData,
		qreal	pixelSize,
		QFont::HintingPreference	hintingPreference = `QFont::PreferDefaultHinting`
	)

Constructs a QRawFont representing the font contained in the supplied fontData for the size (in pixels) given by pixelSize, and using the hinting preference specified by hintingPreference.

Note: The data must contain a TrueType or OpenType font.

QRawFont::QRawFont ( const QRawFont & other )

Creates a QRawFont which is a copy of other.

QRawFont::~QRawFont ( )

Destroys the QRawFont

Method Documentation

bool QRawFont::advancesForGlyphIndexes	(	const quint32 *	glyphIndexes,
		QPointF *	advances,
		int	numGlyphs
	)		const

Returns the QRawFont's advances for each of the glyphIndexes in pixel units. The advances give the distance from the position of a given glyph to where the next glyph should be drawn to make it appear as if the two glyphs are unspaced. The glyph indexes are given with the array glyphIndexes while the results are returned through advances, both of them must have numGlyphs elements.

See also: QTextLine::horizontalAdvance(), QFontMetricsF::width()

bool QRawFont::advancesForGlyphIndexes	(	const quint32 *	glyphIndexes,
		QPointF *	advances,
		int	numGlyphs,
		LayoutFlags	layoutFlags
	)		const

Returns the QRawFont's advances for each of the glyphIndexes in pixel units. The advances give the distance from the position of a given glyph to where the next glyph should be drawn to make it appear as if the two glyphs are unspaced. The glyph indexes are given with the array glyphIndexes while the results are returned through advances, both of them must have numGlyphs elements. How the advances are calculated is controlled by layoutFlags.

See also: QTextLine::horizontalAdvance(), QFontMetricsF::width()

QVector< QPointF > QRawFont::advancesForGlyphIndexes ( const QVector< quint32 > & glyphIndexes ) const

inline

Returns the QRawFont's advances for each of the glyphIndexes in pixel units. The advances give the distance from the position of a given glyph to where the next glyph should be drawn to make it appear as if the two glyphs are unspaced.

See also: QTextLine::horizontalAdvance(), QFontMetricsF::width()

QVector< QPointF > QRawFont::advancesForGlyphIndexes	(	const QVector< quint32 > &	glyphIndexes,
		QRawFont::LayoutFlags	layoutFlags
	)		const

inline

Returns the QRawFont's advances for each of the glyphIndexes in pixel units. The advances give the distance from the position of a given glyph to where the next glyph should be drawn to make it appear as if the two glyphs are unspaced. How the advances are calculated is controlled by layoutFlags.

See also: QTextLine::horizontalAdvance(), QFontMetricsF::width()

QImage QRawFont::alphaMapForGlyph	(	quint32	glyphIndex,
		AntialiasingType	antialiasingType = `SubPixelAntialiasing`,
		const QTransform &	transform = `QTransform()`
	)		const

This method returns a rasterized image of the glyph at the given glyphIndex in the underlying font, using the transform specified. If the QRawFont is not valid, this function will return an invalid QImage.

If antialiasingType is set to QRawFont::SubPixelAntialiasing, then the resulting image will be in QImage::Format_RGB32 and the RGB values of each pixel will represent the subpixel opacities of the pixel in the rasterization of the glyph. Otherwise, the image will be in the format of QImage::Format_Indexed8 and each pixel will contain the opacity of the pixel in the rasterization.

See also: pathForGlyph(), QPainter::drawGlyphRun()

qreal QRawFont::ascent ( ) const

Returns the ascent of this QRawFont in pixel units.

See also: QFontMetricsF::ascent()

qreal QRawFont::averageCharWidth ( ) const

Returns the average character width of this QRawFont in pixel units.

See also: QFontMetricsF::averageCharWidth()

QRectF QRawFont::boundingRect ( quint32 glyphIndex ) const

Returns the smallest rectangle containing the glyph with the given glyphIndex.

qreal QRawFont::descent ( ) const

Returns the descent of this QRawFont in pixel units.

See also: QFontMetricsF::descent()

QString QRawFont::familyName ( ) const

Returns the family name of this QRawFont.

QByteArray QRawFont::fontTable ( const char * tagName ) const

Retrieves the sfnt table named tagName from the underlying physical font, or an empty byte array if no such table was found. The returned font table's byte order is Big Endian, like the sfnt format specifies. The tagName must be four characters long and should be formatted in the default endianness of the current platform.

QRawFont QRawFont::fromFont	(	const QFont &	font,
		QFontDatabase::WritingSystem	writingSystem = `QFontDatabase::Any`
	)

static

Fetches the physical representation based on a font query. The physical font returned is the font that will be preferred by CopperSpice in order to display text in the selected writingSystem.

bool QRawFont::glyphIndexesForChars	(	QStringView	str,
		quint32 *	glyphIndexes,
		int *	numGlyphs
	)		const

Converts a string of unicode points to glyph indexes using the CMAP table in the underlying font. The method works like glyphIndexesForString() except it receive an array (char), the results will be returned though glyphIndexes array and number of glyphs will be set in numGlyphs.

The size of glyphIndexes array must be at least numChars, if that not large enough this method will return false, then resize glyphIndexes from the size returned in numGlyphs.

See also: glyphIndexesForString(), advancesForGlyphIndexes(), QGlyphRun, QTextLayout::glyphRuns(), QTextFragment::glyphRuns()

QVector< quint32 > QRawFont::glyphIndexesForString ( const QString & text ) const

Converts the string of unicode points given by text to glyph indexes using the CMAP table in the underlying font, and returns a vector containing the result.

Note that, in cases where there are other tables in the font that affect the shaping of the text, the returned glyph indexes will not correctly represent the rendering of the text. To get the correctly shaped text, you can use QTextLayout to lay out and shape the text, then call QTextLayout::glyphs() to get the set of glyph index list and QRawFont pairs.

See also: advancesForGlyphIndexes(), glyphIndexesForChars(), QGlyphRun, QTextLayout::glyphRuns(), QTextFragment::glyphRuns()

QFont::HintingPreference QRawFont::hintingPreference ( ) const

Returns the hinting preference used to construct this QRawFont.

See also: QFont::hintingPreference()

bool QRawFont::isValid ( ) const

Returns true if the QRawFont is valid and false otherwise.

qreal QRawFont::leading ( ) const

Returns the leading of this QRawFont in pixel units.

See also: QFontMetricsF::leading()

qreal QRawFont::lineThickness ( ) const

Returns the thickness for drawing lines (underline, overline, etc.) along with text drawn in this font.

void QRawFont::loadFromData	(	const QByteArray &	fontData,
		qreal	pixelSize,
		QFont::HintingPreference	hintingPreference
	)

Replaces the current QRawFont with the font contained in the supplied fontData for the size (in pixels) given by pixelSize, and using the hinting preference specified by hintingPreference. The fontData must contain a TrueType or OpenType font.

See also: loadFromFile()

void QRawFont::loadFromFile	(	const QString &	fileName,
		qreal	pixelSize,
		QFont::HintingPreference	hintingPreference
	)

Replaces the current QRawFont with the contents of the file referenced by fileName for the size (in pixels) given by pixelSize, and using the hinting preference specified by hintingPreference. The file must reference a TrueType or OpenType font.

See also: loadFromData()

qreal QRawFont::maxCharWidth ( ) const

Returns the width of the widest character in the font.

See also: QFontMetricsF::maxWidth()

bool QRawFont::operator!= ( const QRawFont & other ) const

inline

Returns true if this QRawFont is not equal to other. Otherwise, returns false.

QRawFont & QRawFont::operator= ( const QRawFont & other )

Copy assigns from other and returns a reference to this object.

QRawFont & QRawFont::operator= ( QRawFont && other )

inline

Move assigns from other and returns a reference to this object.

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

Returns true if this QRawFont is equal to other. Otherwise, returns false.

QPainterPath QRawFont::pathForGlyph ( quint32 glyphIndex ) const

This function returns the shape of the glyph at a given glyphIndex in the underlying font if the QRawFont is valid. Otherwise, it returns an empty QPainterPath. The returned glyph will always be unhinted.

See also: alphaMapForGlyph(), QPainterPath::addText()

qreal QRawFont::pixelSize ( ) const

Returns the pixel size set for this QRawFont. The pixel size affects how glyphs are rasterized, the size of glyphs returned by pathForGlyph(), and is used to convert internal metrics from design units to logical pixel units.

See also: setPixelSize()

void QRawFont::setPixelSize ( qreal pixelSize )

Sets the pixel size with which this font should be rendered to pixelSize.

See also: pixelSize()

QFont::Style QRawFont::style ( ) const

Returns the style of this QRawFont.

See also: QFont::style()

QString QRawFont::styleName ( ) const

Returns the style name of this QRawFont.

See also: QFont::styleName()

QList< QFontDatabase::WritingSystem > QRawFont::supportedWritingSystems ( ) const

Returns a list of writing systems supported by the font according to designer supplied information in the font file. Please note that this does not guarantee support for a specific unicode point in the font. You can use the supportsCharacter() to check support for a single, specific character.

See also: supportsCharacter()

bool QRawFont::supportsCharacter ( QChar character ) const

Returns true if the font has a glyph that corresponds to the given character.

See also: supportedWritingSystems()

bool QRawFont::supportsCharacter ( quint32 ucs4 ) const

Returns true if the font has a glyph that corresponds to the UCS-4 encoded character ucs4.

See also: supportedWritingSystems()

void QRawFont::swap ( QRawFont & other )

inline

Swaps the raw font other with this raw font. This operation is very fast and never fails.

qreal QRawFont::underlinePosition ( ) const

Returns the position from baseline for drawing underlines below the text rendered with this font.

qreal QRawFont::unitsPerEm ( ) const

Returns the number of design units define the width and height of the em square for this QRawFont. This value is used together with the pixel size when converting design metrics to pixel units, as the internal metrics are specified in design units and the pixel size gives the size of 1 em in pixels.

See also: pixelSize(), setPixelSize()

int QRawFont::weight ( ) const

Returns the weight of this QRawFont.

See also: QFont::weight()

qreal QRawFont::xHeight ( ) const

Returns the xHeight of this QRawFont in pixel units.

See also: QFontMetricsF::xHeight()

Public Types

Public Methods

Static Public Methods

Friends

Detailed Description

Constructiong a QRawFont

Member Enumeration Documentation

Constructor & Destructor Documentation

Method Documentation