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44 #if !defined(QT_NO_RAWFONT)
46 #include "qglyphrun.h"
47 #include "qglyphrun_p.h"
53 \brief The QGlyphRun class provides direct access to the internal glyphs in a font.
59 When Qt displays a string of text encoded in Unicode, it will first convert the Unicode points
60 into a list of glyph indexes and a list of positions based on one or more fonts. The Unicode
61 representation of the text and the QFont object will in this case serve as a convenient
62 abstraction that hides the details of what actually takes place when displaying the text
63 on-screen. For instance, by the time the text actually reaches the screen, it may be represented
64 by a set of fonts in addition to the one specified by the user, e.g. in case the originally
65 selected font did not support all the writing systems contained in the text.
67 Under certain circumstances, it can be useful as an application developer to have more low-level
68 control over which glyphs in a specific font are drawn to the screen. This could for instance
69 be the case in applications that use an external font engine and text shaper together with Qt.
70 QGlyphRun provides an interface to the raw data needed to get text on the screen. It
71 contains a list of glyph indexes, a position for each glyph and a font.
73 It is the user's responsibility to ensure that the selected font actually contains the
74 provided glyph indexes.
76 QTextLayout::glyphRuns() or QTextFragment::glyphRuns() can be used to convert unicode encoded
77 text into a list of QGlyphRun objects, and QPainter::drawGlyphRun() can be used to draw the
80 \note Please note that QRawFont is considered local to the thread in which it is constructed.
81 This in turn means that a new QRawFont will have to be created and set on the QGlyphRun if it is
82 moved to a different thread. If the QGlyphRun contains a reference to a QRawFont from a different
83 thread than the current, it will not be possible to draw the glyphs using a QPainter, as the
84 QRawFont is considered invalid and inaccessible in this case.
89 Constructs an empty QGlyphRun object.
91 QGlyphRun::QGlyphRun() : d(new QGlyphRunPrivate)
96 Constructs a QGlyphRun object which is a copy of \a other.
98 QGlyphRun::QGlyphRun(const QGlyphRun &other)
104 Destroys the QGlyphRun.
106 QGlyphRun::~QGlyphRun()
108 // Required for QExplicitlySharedDataPointer
114 void QGlyphRun::detach()
121 Assigns \a other to this QGlyphRun object.
123 QGlyphRun &QGlyphRun::operator=(const QGlyphRun &other)
130 Compares \a other to this QGlyphRun object. Returns true if the list of glyph indexes,
131 the list of positions and the font are all equal, otherwise returns false.
133 bool QGlyphRun::operator==(const QGlyphRun &other) const
138 if ((d->glyphIndexDataSize != other.d->glyphIndexDataSize)
139 || (d->glyphPositionDataSize != other.d->glyphPositionDataSize)) {
143 for (int i=0; i<qMax(d->glyphIndexDataSize, d->glyphPositionDataSize); ++i) {
144 if (i < d->glyphIndexDataSize && d->glyphIndexData[i] != other.d->glyphIndexData[i])
147 if (i < d->glyphPositionDataSize && d->glyphPositionData[i] != other.d->glyphPositionData[i])
152 return (d->overline == other.d->overline
153 && d->underline == other.d->underline
154 && d->strikeOut == other.d->strikeOut
155 && d->rawFont == other.d->rawFont);
159 Compares \a other to this QGlyphRun object. Returns true if any of the list of glyph
160 indexes, the list of positions or the font are different, otherwise returns false.
162 bool QGlyphRun::operator!=(const QGlyphRun &other) const
164 return !(*this == other);
168 Returns the font selected for this QGlyphRun object.
172 QRawFont QGlyphRun::rawFont() const
178 Sets the font in which to look up the glyph indexes to \a font.
180 \sa rawFont(), setGlyphIndexes()
182 void QGlyphRun::setRawFont(const QRawFont &rawFont)
185 d->rawFont = rawFont;
189 Returns the glyph indexes for this QGlyphRun object.
191 \sa setGlyphIndexes(), setPositions()
193 QVector<quint32> QGlyphRun::glyphIndexes() const
195 if (d->glyphIndexes.constData() == d->glyphIndexData) {
196 return d->glyphIndexes;
198 QVector<quint32> indexes(d->glyphIndexDataSize);
199 qMemCopy(indexes.data(), d->glyphIndexData, d->glyphIndexDataSize * sizeof(quint32));
205 Set the glyph indexes for this QGlyphRun object to \a glyphIndexes. The glyph indexes must
206 be valid for the selected font.
208 void QGlyphRun::setGlyphIndexes(const QVector<quint32> &glyphIndexes)
211 d->glyphIndexes = glyphIndexes; // Keep a reference to the QVector to avoid copying
212 d->glyphIndexData = glyphIndexes.constData();
213 d->glyphIndexDataSize = glyphIndexes.size();
217 Returns the position of the edge of the baseline for each glyph in this set of glyph indexes.
219 QVector<QPointF> QGlyphRun::positions() const
221 if (d->glyphPositions.constData() == d->glyphPositionData) {
222 return d->glyphPositions;
224 QVector<QPointF> glyphPositions(d->glyphPositionDataSize);
225 qMemCopy(glyphPositions.data(), d->glyphPositionData,
226 d->glyphPositionDataSize * sizeof(QPointF));
227 return glyphPositions;
232 Sets the positions of the edge of the baseline for each glyph in this set of glyph indexes to
235 void QGlyphRun::setPositions(const QVector<QPointF> &positions)
238 d->glyphPositions = positions; // Keep a reference to the vector to avoid copying
239 d->glyphPositionData = positions.constData();
240 d->glyphPositionDataSize = positions.size();
244 Clears all data in the QGlyphRun object.
246 void QGlyphRun::clear()
249 d->rawFont = QRawFont();
250 d->strikeOut = false;
252 d->underline = false;
254 setPositions(QVector<QPointF>());
255 setGlyphIndexes(QVector<quint32>());
259 Sets the glyph indexes and positions of this QGlyphRun to use the first \a size
260 elements in the arrays \a glyphIndexArray and \a glyphPositionArray. The data is
261 \e not copied. The caller must guarantee that the arrays are not deleted as long
262 as this QGlyphRun and any copies of it exists.
264 \sa setGlyphIndexes(), setPositions()
266 void QGlyphRun::setRawData(const quint32 *glyphIndexArray, const QPointF *glyphPositionArray,
270 d->glyphIndexes.clear();
271 d->glyphPositions.clear();
273 d->glyphIndexData = glyphIndexArray;
274 d->glyphPositionData = glyphPositionArray;
275 d->glyphIndexDataSize = d->glyphPositionDataSize = size;
279 Returns true if this QGlyphRun should be painted with an overline decoration.
283 bool QGlyphRun::overline() const
289 Indicates that this QGlyphRun should be painted with an overline decoration if \a overline is true.
290 Otherwise the QGlyphRun should be painted with no overline decoration.
294 void QGlyphRun::setOverline(bool overline)
297 d->overline = overline;
301 Returns true if this QGlyphRun should be painted with an underline decoration.
305 bool QGlyphRun::underline() const
311 Indicates that this QGlyphRun should be painted with an underline decoration if \a underline is
312 true. Otherwise the QGlyphRun should be painted with no underline decoration.
316 void QGlyphRun::setUnderline(bool underline)
319 d->underline = underline;
323 Returns true if this QGlyphRun should be painted with a strike out decoration.
327 bool QGlyphRun::strikeOut() const
333 Indicates that this QGlyphRun should be painted with an strike out decoration if \a strikeOut is
334 true. Otherwise the QGlyphRun should be painted with no strike out decoration.
338 void QGlyphRun::setStrikeOut(bool strikeOut)
341 d->strikeOut = strikeOut;
345 Returns the smallest rectangle that contains all glyphs in this QGlyphRun.
349 QRectF QGlyphRun::boundingRect() const
351 qreal minX, minY, maxX, maxY;
353 for (int i=0; i<qMin(d->glyphPositions.size(), d->glyphIndexes.size()); ++i) {
354 QRectF glyphRect = d->rawFont.boundingRect(d->glyphIndexes.at(i));
355 glyphRect.translate(d->glyphPositions.at(i));
358 minX = glyphRect.left();
359 minY = glyphRect.top();
360 maxX = glyphRect.right();
361 maxY = glyphRect.bottom();
363 minX = qMin(glyphRect.left(), minX);
364 minY = qMin(glyphRect.top(), minY);
365 maxX = qMax(glyphRect.right(),maxX);
366 maxY = qMax(glyphRect.bottom(), maxY);
370 return QRectF(QPointF(minX, minY), QPointF(maxX, maxY));
375 #endif // QT_NO_RAWFONT