The QGlyphRun class provides direct access to the internal glyphs in a font. 更多...
The QGlyphRun class provides direct access to the internal glyphs in a font.
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.
构造空 QGlyphRun 对象。
构造 QGlyphRun object which is a copy of other .
Clears all data in the QGlyphRun 对象。
Returns the glyph indexes for this QGlyphRun 对象。
另请参阅 setGlyphIndexes () 和 setPositions ().
返回 true，若此 QGlyphRun should be painted with an overline decoration.
另请参阅 setOverline ().
Returns the position of the edge of the baseline for each glyph in this set of glyph indexes.
另请参阅 setPositions ().
Returns the font selected for this QGlyphRun 对象。
另请参阅 setRawFont ().
Set the glyph indexes for this QGlyphRun object to glyphIndexes 。 glyph indexes must be valid for the selected font.
另请参阅 glyphIndexes ().
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 ().
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 ().
Sets the font specified by rawFont to be the font used to look up the glyph indexes.
另请参阅 rawFont () and setGlyphIndexes ().
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 ().
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 ().
返回 true，若此 QGlyphRun should be painted with a strike out decoration.
另请参阅 setStrikeOut ().
返回 true，若此 QGlyphRun should be painted with an underline decoration.
另请参阅 setUnderline ().
