QGlyphRun 类

QGlyphRun 类提供对字体内部字形的直接访问。更多...

头：	#include <QGlyphRun>
CMake:	find_package(Qt6 REQUIRED COMPONENTS Gui) target_link_libraries(mytarget PRIVATE Qt6::Gui)
qmake:	QT += gui

所有成员列表，包括继承成员
QGlyphRun is part of 隐式共享类 .

公共类型

enum	GlyphRunFlag { Overline, Underline, StrikeOut, RightToLeft, SplitLigature }
flags	GlyphRunFlags

公共函数

	QGlyphRun ()
	QGlyphRun (const QGlyphRun & other )
	~QGlyphRun ()
QRectF	boundingRect () const
void	clear ()
QGlyphRun::GlyphRunFlags	flags () const
QList<quint32>	glyphIndexes () const
bool	isEmpty () const
bool	isRightToLeft () const
bool	overline () const
QList<QPointF>	positions () const
QRawFont	rawFont () const
void	setBoundingRect (const QRectF & boundingRect )
void	setFlag (QGlyphRun::GlyphRunFlag flag , bool enabled = true)
void	setFlags (QGlyphRun::GlyphRunFlags flags )
void	setGlyphIndexes (const QList<quint32> & glyphIndexes )
void	setOverline (bool overline )
void	setPositions (const QList<QPointF> & positions )
void	setRawData (const quint32 * glyphIndexArray , const QPointF * glyphPositionArray , int size )
void	setRawFont (const QRawFont & rawFont )
void	setRightToLeft (bool rightToLeft )
`(从 6.5 起)` void	setSourceString (const QString & sourceString )
void	setStrikeOut (bool strikeOut )
`(从 6.5 起)` void	setStringIndexes (const QList<qsizetype> & stringIndexes )
void	setUnderline (bool underline )
`(从 6.5 起)` QString	sourceString () const
bool	strikeOut () const
`(从 6.5 起)` QList<qsizetype>	stringIndexes () const
void	swap (QGlyphRun & other )
bool	underline () const
bool	operator!= (const QGlyphRun & other ) const
QGlyphRun &	operator= (const QGlyphRun & other )
bool	operator== (const QGlyphRun & other ) const

详细描述

When Qt displays a string of text encoded in Unicode, it will first convert the Unicode points into a list of glyph indexes and a list of positions based on one or more fonts. The Unicode representation of the text and the QFont object will in this case serve as a convenient abstraction that hides the details of what actually takes place when displaying the text on-screen. For instance, by the time the text actually reaches the screen, it may be represented by a set of fonts in addition to the one specified by the user, e.g. in case the originally selected font did not support all the writing systems contained in the text.

Under certain circumstances, it can be useful as an application developer to have more low-level control over which glyphs in a specific font are drawn to the screen. This could for instance be the case in applications that use an external font engine and text shaper together with Qt. QGlyphRun provides an interface to the raw data needed to get text on the screen. It contains a list of glyph indexes, a position for each glyph and a font.

It is the user's responsibility to ensure that the selected font actually contains the provided glyph indexes.

QTextLayout::glyphRuns () 或 QTextFragment::glyphRuns () can be used to convert unicode encoded text into a list of QGlyphRun objects, and QPainter::drawGlyphRun () can be used to draw the glyphs.

注意： 请注意 QRawFont is considered local to the thread in which it is constructed. This in turn means that a new QRawFont will have to be created and set on the QGlyphRun if it is moved to a different thread. If the QGlyphRun contains a reference to a QRawFont from a different thread than the current, it will not be possible to draw the glyphs using a QPainter , as the QRawFont is considered invalid and inaccessible in this case.

成员类型文档编制

enum QGlyphRun:: GlyphRunFlag
flags QGlyphRun:: GlyphRunFlags

This enum describes flags that alter the way the run of glyphs might be presented or behave in a visual layout. The layout which generates the glyph runs can set these flags based on relevant internal data, to retain information needed to present the text as intended by the user of the layout.

常量	值	描述
`QGlyphRun::Overline`	`0x01`	Indicates that the glyphs should be visualized together with an overline.
`QGlyphRun::Underline`	`0x02`	Indicates that the glyphs should be visualized together with an underline.
`QGlyphRun::StrikeOut`	`0x04`	Indicates that the glyphs should be struck out visually.
`QGlyphRun::RightToLeft`	`0x08`	Indicates that the glyphs are ordered right to left. This can affect the positioning of other screen elements that are relative to the glyph run, such as an inline text object.
`QGlyphRun::SplitLigature`	`0x10`	Indicates that the glyph run splits a ligature glyph. This means that a ligature glyph is included in the run, but the characters represented by it corresponds only to part of that ligature. The glyph run's boundingRect () function can in this case be used to retrieve the area covered by glyphs that correspond to the characters represented by the glyph run. When visualizing the glyphs, care needs to be taken to clip to this bounding rect to ensure that only the corresponding part of the ligature is painted. In particular, this can be the case when retrieving a glyph run from a QTextLayout for a specific character range, e.g. when retrieving the selected area of a QTextLayout .

The GlyphRunFlags type is a typedef for QFlags <GlyphRunFlag>. It stores an OR combination of GlyphRunFlag values.

成员函数文档编制

QGlyphRun:: QGlyphRun ()

构造空的 QGlyphRun 对象。

QGlyphRun:: QGlyphRun (const QGlyphRun & other )

构造副本 QGlyphRun 对象为 other .

`[noexcept]` QGlyphRun:: ~QGlyphRun ()

销毁 QGlyphRun .

QRectF QGlyphRun:: boundingRect () const

Returns the smallest rectangle that contains all glyphs in this QGlyphRun . If a bounding rect has been set using setBoundingRect (), then this will be returned. Otherwise the bounding rect will be calculated based on the font metrics of the glyphs in the glyph run.

另请参阅 setBoundingRect ().

void QGlyphRun:: clear ()

清零所有数据从 QGlyphRun 对象。

QGlyphRun::GlyphRunFlags QGlyphRun:: flags () const

返回设置标志为此 QGlyphRun .

另请参阅 setFlags (), setFlag ()，和 setFlag ().

QList < quint32 > QGlyphRun:: glyphIndexes () const

Returns the glyph indexes for this QGlyphRun 对象。

另请参阅 setGlyphIndexes () 和 setPositions ().

bool QGlyphRun:: isEmpty () const

返回 true 若 QGlyphRun 不包含任何字形。

bool QGlyphRun:: isRightToLeft () const

返回 true 若此 QGlyphRun contains glyphs that are painted from the right to the left.

另请参阅 setRightToLeft () 和 flags ().

bool QGlyphRun:: overline () const

返回 true 若此 QGlyphRun should be painted with an overline decoration.

另请参阅 setOverline () 和 flags ().

QList < QPointF > QGlyphRun:: positions () const

Returns the position of the edge of the baseline for each glyph in this set of glyph indexes.

另请参阅 setPositions ().

QRawFont QGlyphRun:: rawFont () const

Returns the font selected for this QGlyphRun 对象。

另请参阅 setRawFont ().

void QGlyphRun:: setBoundingRect (const QRectF & boundingRect )

Sets the bounding rect of the glyphs in this QGlyphRun 到 boundingRect . This rectangle will be returned by boundingRect () unless it is null, in which case the bounding rectangle of the glyphs in the glyph run will be returned instead.

注意： Unless you are implementing text shaping, you should not have to use this function. It is used specifically when the QGlyphRun should represent an area which is smaller than the area of the glyphs it contains. This could happen e.g. if the glyph run is retrieved by calling QTextLayout::glyphRuns () and the specified range only includes part of a ligature (where two or more characters are combined to a single glyph.) When this is the case, the bounding rect should only include the appropriate part of the ligature glyph, based on a calculation of the average width of the characters in the ligature.

In order to support such a case (an example is selections which should be drawn with a different color than the main text color), it is necessary to clip the painting mechanism to the rectangle returned from boundingRect () to avoid drawing the entire ligature glyph.

另请参阅 boundingRect ().

void QGlyphRun:: setFlag ( QGlyphRun::GlyphRunFlag flag , bool enabled = true)

若 enabled 为 true，则 flag 被启用；否则，被禁用。

另请参阅 flags () 和 setFlags ().

void QGlyphRun:: setFlags ( QGlyphRun::GlyphRunFlags flags )

设置标志为此 QGlyphRun to flags .

另请参阅 setFlag () 和 flags ().

void QGlyphRun:: setGlyphIndexes (const QList < quint32 > & glyphIndexes )

Set the glyph indexes for this QGlyphRun 对象到 glyphIndexes . The glyph indexes must be valid for the selected font.

另请参阅 glyphIndexes ().

void QGlyphRun:: setOverline ( bool overline )

Indicates that this QGlyphRun should be painted with an overline decoration if overline is true. Otherwise the QGlyphRun should be painted with no overline decoration.

另请参阅 overline (), setFlag ()，和 setFlags ().

void QGlyphRun:: setPositions (const QList < QPointF > & positions )

Sets the positions of the edge of the baseline for each glyph in this set of glyph indexes to positions .

另请参阅 positions ().

void QGlyphRun:: setRawData (const quint32 * glyphIndexArray , const QPointF * glyphPositionArray , int size )

Sets the glyph indexes and positions of this QGlyphRun to use the first size elements in the arrays glyphIndexArray and glyphPositionArray . The data is not copied. The caller must guarantee that the arrays are not deleted as long as this QGlyphRun and any copies of it exists.

另请参阅 setGlyphIndexes () 和 setPositions ().

void QGlyphRun:: setRawFont (const QRawFont & rawFont )

Sets the font in which to look up the glyph indexes to the rawFont 指定。

另请参阅 rawFont () 和 setGlyphIndexes ().

void QGlyphRun:: setRightToLeft ( bool rightToLeft )

Indicates that this QGlyphRun contains glyphs that should be ordered from the right to left if rightToLeft is true. Otherwise the order of the glyphs is assumed to be left to right.

另请参阅 isRightToLeft (), setFlag ()，和 setFlags ().

`[since 6.5]` void QGlyphRun:: setSourceString (const QString & sourceString )

Set the string corresponding to the glyph run to sourceString . If set, the indexes returned by stringIndexes () should be indexes into this string.

该函数在 Qt 6.5 引入。

另请参阅 sourceString () 和 stringIndexes ().

void QGlyphRun:: setStrikeOut ( bool strikeOut )

Indicates that this QGlyphRun should be painted with an strike out decoration if strikeOut is true. Otherwise the QGlyphRun should be painted with no strike out decoration.

另请参阅 strikeOut (), setFlag ()，和 setFlags ().

`[since 6.5]` void QGlyphRun:: setStringIndexes (const QList < qsizetype > & stringIndexes )

Sets the list of string indexes corresponding to the glyph indexes to stringIndexes

见 stringIndexes () for more details on the conventions of this list.

该函数在 Qt 6.5 引入。

另请参阅 stringIndexes () 和 sourceString ().

void QGlyphRun:: setUnderline ( bool underline )

Indicates that this QGlyphRun should be painted with an underline decoration if underline is true. Otherwise the QGlyphRun should be painted with no underline decoration.

另请参阅 underline (), setFlag ()，和 setFlags ().

`[since 6.5]` QString QGlyphRun:: sourceString () const

Returns the string corresponding to the glyph run, if the glyph run has been created from a string and the string has been requested from the layout.

该函数在 Qt 6.5 引入。

另请参阅 setSourceString (), stringIndexes ()，和 QTextLayout::glyphRuns ().

bool QGlyphRun:: strikeOut () const

返回 true 若此 QGlyphRun should be painted with a strike out decoration.

另请参阅 setStrikeOut () 和 flags ().

`[since 6.5]` QList < qsizetype > QGlyphRun:: stringIndexes () const

Returns the string indexes corresponding to each glyph index, if the glyph run has been constructed from a string and string indexes have been requested from the layout. In this case, the length of the returned vector will correspond to the length of glyphIndexes (). In other cases, it will be empty.

Since a single glyph may correspond to multiple characters in the source string, there may be gaps in the list of string indexes. For instance, if the string "first" is processed by a font which contains a ligature for the character pair "fi", then the five character string will generate a glyph run consisting of only four glyphs. Then the glyph indexes may in this case be (1, 2, 3, 4) (four arbitrary glyph indexes) whereas the string indexes would be (0, 2, 3, 4). The glyphs are in the logical order of the string, thus it is implied that the first glyphs spans characters 0 and 1 in this case.

Inversely, a single character may also generate multiple glyphs, in which case there will be duplicate entries in the list of string indexes.

The string indexes correspond to the string, optionally available through sourceString ().

该函数在 Qt 6.5 引入。

另请参阅 setStringIndexes (), sourceString ()，和 QTextLayout::glyphRuns ().

`[noexcept]` void QGlyphRun:: swap ( QGlyphRun & other )

Swaps this glyph run instance with other 。此函数非常快且从不失败。

bool QGlyphRun:: underline () const

返回 true 若此 QGlyphRun should be painted with an underline decoration.

另请参阅 setUnderline () 和 flags ().

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

比较 other 到此 QGlyphRun 对象。返回 true if any of the list of glyph indexes, the list of positions or the font are different, otherwise returns false .

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

赋值 other 到此 QGlyphRun 对象。

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

比较 other 到此 QGlyphRun 对象。返回 true if the list of glyph indexes, the list of positions and the font are all equal, otherwise returns false .

QGlyphRun 类

公共类型

公共函数

详细描述

成员类型文档编制

enum QGlyphRun:: GlyphRunFlag flags QGlyphRun:: GlyphRunFlags

成员函数文档编制

QGlyphRun:: QGlyphRun ()

QGlyphRun:: QGlyphRun (const QGlyphRun & other )

[noexcept] QGlyphRun:: ~QGlyphRun ()

QRectF QGlyphRun:: boundingRect () const

void QGlyphRun:: clear ()

QGlyphRun::GlyphRunFlags QGlyphRun:: flags () const

QList < quint32 > QGlyphRun:: glyphIndexes () const

bool QGlyphRun:: isEmpty () const

bool QGlyphRun:: isRightToLeft () const

bool QGlyphRun:: overline () const

QList < QPointF > QGlyphRun:: positions () const

QRawFont QGlyphRun:: rawFont () const

void QGlyphRun:: setBoundingRect (const QRectF & boundingRect )

void QGlyphRun:: setFlag ( QGlyphRun::GlyphRunFlag flag , bool enabled = true)

void QGlyphRun:: setFlags ( QGlyphRun::GlyphRunFlags flags )

void QGlyphRun:: setGlyphIndexes (const QList < quint32 > & glyphIndexes )

void QGlyphRun:: setOverline ( bool overline )

void QGlyphRun:: setPositions (const QList < QPointF > & positions )

void QGlyphRun:: setRawData (const quint32 * glyphIndexArray , const QPointF * glyphPositionArray , int size )

void QGlyphRun:: setRawFont (const QRawFont & rawFont )

void QGlyphRun:: setRightToLeft ( bool rightToLeft )

[since 6.5] void QGlyphRun:: setSourceString (const QString & sourceString )

void QGlyphRun:: setStrikeOut ( bool strikeOut )

[since 6.5] void QGlyphRun:: setStringIndexes (const QList < qsizetype > & stringIndexes )

void QGlyphRun:: setUnderline ( bool underline )

[since 6.5] QString QGlyphRun:: sourceString () const

bool QGlyphRun:: strikeOut () const

[since 6.5] QList < qsizetype > QGlyphRun:: stringIndexes () const

[noexcept] void QGlyphRun:: swap ( QGlyphRun & other )

bool QGlyphRun:: underline () const

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

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

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

内容

enum QGlyphRun:: GlyphRunFlag
flags QGlyphRun:: GlyphRunFlags

`[noexcept]` QGlyphRun:: ~QGlyphRun ()

`[since 6.5]` void QGlyphRun:: setSourceString (const QString & sourceString )

`[since 6.5]` void QGlyphRun:: setStringIndexes (const QList < qsizetype > & stringIndexes )

`[since 6.5]` QString QGlyphRun:: sourceString () const

`[since 6.5]` QList < qsizetype > QGlyphRun:: stringIndexes () const

`[noexcept]` void QGlyphRun:: swap ( QGlyphRun & other )