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39 | |
40 | #include "qplatformfontdatabase.h" |
41 | #include <QtGui/private/qfontengine_p.h> |
42 | #include <QtGui/private/qfontdatabase_p.h> |
43 | #include <QtGui/QGuiApplication> |
44 | #include <QtGui/QScreen> |
45 | #include <qpa/qplatformscreen.h> |
46 | #include <QtCore/QLibraryInfo> |
47 | #include <QtCore/QDir> |
48 | #include <QtCore/QMetaEnum> |
49 | #include <QtCore/qendian.h> |
50 | |
51 | #include <algorithm> |
52 | #include <iterator> |
53 | |
54 | QT_BEGIN_NAMESPACE |
55 | |
56 | Q_LOGGING_CATEGORY(lcQpaFonts, "qt.qpa.fonts" ) |
57 | |
58 | void qt_registerFont(const QString &familyname, const QString &stylename, |
59 | const QString &foundryname, int weight, |
60 | QFont::Style style, int stretch, bool antialiased, |
61 | bool scalable, int pixelSize, bool fixedPitch, |
62 | const QSupportedWritingSystems &writingSystems, void *hanlde); |
63 | |
64 | void qt_registerFontFamily(const QString &familyName); |
65 | void qt_registerAliasToFontFamily(const QString &familyName, const QString &alias); |
66 | bool qt_isFontFamilyPopulated(const QString &familyName); |
67 | |
68 | /*! |
69 | Registers a font with the given set of attributes describing the font's |
70 | foundry, family name, style and stretch information, pixel size, and |
71 | supported writing systems. Additional information about whether the font |
72 | can be scaled and antialiased can also be provided. |
73 | |
74 | The foundry name and font family are described by \a foundryName and |
75 | \a familyName. The font weight (light, normal, bold, etc.), style (normal, |
76 | oblique, italic) and stretch information (condensed, expanded, unstretched, |
77 | etc.) are specified by \a weight, \a style and \a stretch. |
78 | |
79 | Some fonts can be antialiased and scaled; \a scalable and \a antialiased |
80 | can be set to true for fonts with these attributes. The intended pixel |
81 | size of non-scalable fonts is specified by \a pixelSize; this value will be |
82 | ignored for scalable fonts. |
83 | |
84 | The writing systems supported by the font are specified by the |
85 | \a writingSystems argument. |
86 | |
87 | \sa registerFontFamily() |
88 | */ |
89 | void QPlatformFontDatabase::registerFont(const QString &familyname, const QString &stylename, |
90 | const QString &foundryname, QFont::Weight weight, |
91 | QFont::Style style, QFont::Stretch stretch, bool antialiased, |
92 | bool scalable, int pixelSize, bool fixedPitch, |
93 | const QSupportedWritingSystems &writingSystems, void *usrPtr) |
94 | { |
95 | if (scalable) |
96 | pixelSize = 0; |
97 | |
98 | qt_registerFont(familyname, stylename, foundryname, weight, style, |
99 | stretch, antialiased, scalable, pixelSize, |
100 | fixedPitch, writingSystems, usrPtr); |
101 | } |
102 | |
103 | /*! |
104 | Registers a font family with the font database. The font will be |
105 | lazily populated by a callback to populateFamily() when the font |
106 | database determines that the family needs population. |
107 | |
108 | \sa populateFamily(), registerFont() |
109 | */ |
110 | void QPlatformFontDatabase::registerFontFamily(const QString &familyName) |
111 | { |
112 | qt_registerFontFamily(familyName); |
113 | } |
114 | |
115 | class QWritingSystemsPrivate |
116 | { |
117 | public: |
118 | QWritingSystemsPrivate() |
119 | : ref(1) |
120 | , list(QFontDatabase::WritingSystemsCount, false) |
121 | { |
122 | } |
123 | |
124 | QWritingSystemsPrivate(const QWritingSystemsPrivate *other) |
125 | : ref(1) |
126 | , list(other->list) |
127 | { |
128 | } |
129 | |
130 | QAtomicInt ref; |
131 | QList<bool> list; |
132 | }; |
133 | |
134 | /*! |
135 | Constructs a new object to handle supported writing systems. |
136 | */ |
137 | QSupportedWritingSystems::QSupportedWritingSystems() |
138 | { |
139 | d = new QWritingSystemsPrivate; |
140 | } |
141 | |
142 | /*! |
143 | Constructs a copy of the \a other writing systems object. |
144 | */ |
145 | QSupportedWritingSystems::QSupportedWritingSystems(const QSupportedWritingSystems &other) |
146 | { |
147 | d = other.d; |
148 | d->ref.ref(); |
149 | } |
150 | |
151 | /*! |
152 | Constructs a copy of the \a other writing systems object. |
153 | */ |
154 | QSupportedWritingSystems &QSupportedWritingSystems::operator=(const QSupportedWritingSystems &other) |
155 | { |
156 | if (d != other.d) { |
157 | other.d->ref.ref(); |
158 | if (!d->ref.deref()) |
159 | delete d; |
160 | d = other.d; |
161 | } |
162 | return *this; |
163 | } |
164 | |
165 | #ifndef QT_NO_DEBUG_STREAM |
166 | QDebug operator<<(QDebug debug, const QSupportedWritingSystems &sws) |
167 | { |
168 | QMetaObject mo = QFontDatabase::staticMetaObject; |
169 | QMetaEnum me = mo.enumerator(mo.indexOfEnumerator("WritingSystem" )); |
170 | |
171 | QDebugStateSaver saver(debug); |
172 | debug.nospace() << "QSupportedWritingSystems(" ; |
173 | int i = sws.d->list.indexOf(true); |
174 | while (i > 0) { |
175 | debug << me.valueToKey(i); |
176 | i = sws.d->list.indexOf(true, i + 1); |
177 | if (i > 0) |
178 | debug << ", " ; |
179 | } |
180 | debug << ")" ; |
181 | return debug; |
182 | } |
183 | #endif |
184 | |
185 | /*! |
186 | Destroys the supported writing systems object. |
187 | */ |
188 | QSupportedWritingSystems::~QSupportedWritingSystems() |
189 | { |
190 | if (!d->ref.deref()) |
191 | delete d; |
192 | } |
193 | |
194 | /*! |
195 | \internal |
196 | */ |
197 | void QSupportedWritingSystems::detach() |
198 | { |
199 | if (d->ref.loadRelaxed() != 1) { |
200 | QWritingSystemsPrivate *newd = new QWritingSystemsPrivate(d); |
201 | if (!d->ref.deref()) |
202 | delete d; |
203 | d = newd; |
204 | } |
205 | } |
206 | |
207 | /*! |
208 | Sets or clears support for the specified \a writingSystem based on the |
209 | value given by \a support. |
210 | */ |
211 | void QSupportedWritingSystems::setSupported(QFontDatabase::WritingSystem writingSystem, bool support) |
212 | { |
213 | detach(); |
214 | d->list[writingSystem] = support; |
215 | } |
216 | |
217 | /*! |
218 | Returns \c true if the writing system specified by \a writingSystem is |
219 | supported; otherwise returns \c false. |
220 | */ |
221 | bool QSupportedWritingSystems::supported(QFontDatabase::WritingSystem writingSystem) const |
222 | { |
223 | return d->list.at(writingSystem); |
224 | } |
225 | |
226 | /*! |
227 | \class QSupportedWritingSystems |
228 | \brief The QSupportedWritingSystems class is used when registering fonts with the internal Qt |
229 | fontdatabase. |
230 | \ingroup painting |
231 | \inmodule QtGui |
232 | |
233 | Its to provide an easy to use interface for indicating what writing systems a specific font |
234 | supports. |
235 | |
236 | */ |
237 | |
238 | /*! |
239 | \internal |
240 | */ |
241 | QPlatformFontDatabase::~QPlatformFontDatabase() |
242 | { |
243 | } |
244 | |
245 | /*! |
246 | This function is called once at startup by Qt's internal font database. |
247 | Reimplement this function in a subclass for a convenient place to initialize |
248 | the internal font database. |
249 | |
250 | You may lazily populate the database by calling registerFontFamily() instead |
251 | of registerFont(), in which case you'll get a callback to populateFamily() |
252 | when the required family needs population. You then call registerFont() to |
253 | finish population of the family. |
254 | |
255 | The default implementation does nothing. |
256 | */ |
257 | void QPlatformFontDatabase::populateFontDatabase() |
258 | { |
259 | } |
260 | |
261 | /*! |
262 | This function is called whenever a lazily populated family, populated |
263 | through registerFontFamily(), needs full population. |
264 | |
265 | You are expected to fully populate the family by calling registerFont() |
266 | for each font that matches the family name. |
267 | */ |
268 | void QPlatformFontDatabase::populateFamily(const QString &familyName) |
269 | { |
270 | Q_UNUSED(familyName); |
271 | } |
272 | |
273 | /*! |
274 | This function is called whenever the font database is invalidated. |
275 | |
276 | Reimplement this function to clear any internal data structures that |
277 | will need to be rebuilt at the next call to populateFontDatabase(). |
278 | */ |
279 | void QPlatformFontDatabase::invalidate() |
280 | { |
281 | } |
282 | |
283 | /*! |
284 | Returns a multi font engine in the specified \a script to encapsulate \a fontEngine with the |
285 | option to fall back to the fonts given by \a fallbacks if \a fontEngine does not support |
286 | a certain character. |
287 | */ |
288 | QFontEngineMulti *QPlatformFontDatabase::fontEngineMulti(QFontEngine *fontEngine, QChar::Script script) |
289 | { |
290 | return new QFontEngineMulti(fontEngine, script); |
291 | } |
292 | |
293 | /*! |
294 | Returns the font engine that can be used to render the font described by |
295 | the font definition, \a fontDef, in the specified \a script. |
296 | */ |
297 | QFontEngine *QPlatformFontDatabase::fontEngine(const QFontDef &fontDef, void *handle) |
298 | { |
299 | Q_UNUSED(fontDef); |
300 | Q_UNUSED(handle); |
301 | qWarning("This plugin does not support loading system fonts." ); |
302 | return nullptr; |
303 | } |
304 | |
305 | QFontEngine *QPlatformFontDatabase::fontEngine(const QByteArray &fontData, qreal pixelSize, |
306 | QFont::HintingPreference hintingPreference) |
307 | { |
308 | Q_UNUSED(fontData); |
309 | Q_UNUSED(pixelSize); |
310 | Q_UNUSED(hintingPreference); |
311 | qWarning("This plugin does not support font engines created directly from font data" ); |
312 | return nullptr; |
313 | } |
314 | |
315 | /*! |
316 | Adds an application font described by the font contained supplied \a fontData |
317 | or using the font contained in the file referenced by \a fileName. Returns |
318 | a list of family names, or an empty list if the font could not be added. |
319 | |
320 | If \a applicationFont is non-null, its \c properties list should be filled |
321 | with information from the loaded fonts. This is exposed through FontLoader in |
322 | Qt Quick where it is needed for disambiguating fonts in the same family. When |
323 | the function exits, the \a applicationFont should contain an entry of properties |
324 | per font in the file, or it should be empty if no font was loaded. |
325 | |
326 | \note The default implementation of this function does not add an application |
327 | font. Subclasses should reimplement this function to perform the necessary |
328 | loading and registration of fonts. |
329 | */ |
330 | QStringList QPlatformFontDatabase::addApplicationFont(const QByteArray &fontData, const QString &fileName, QFontDatabasePrivate::ApplicationFont *applicationFont) |
331 | { |
332 | Q_UNUSED(fontData); |
333 | Q_UNUSED(fileName); |
334 | Q_UNUSED(applicationFont); |
335 | |
336 | if (applicationFont != nullptr) |
337 | applicationFont->properties.clear(); |
338 | |
339 | qWarning("This plugin does not support application fonts" ); |
340 | |
341 | return QStringList(); |
342 | } |
343 | |
344 | /*! |
345 | Releases the specified font \a handle. |
346 | */ |
347 | void QPlatformFontDatabase::releaseHandle(void *handle) |
348 | { |
349 | QByteArray *fileDataPtr = static_cast<QByteArray *>(handle); |
350 | delete fileDataPtr; |
351 | } |
352 | |
353 | /*! |
354 | Returns the directory containing the fonts used by the database. |
355 | */ |
356 | QString QPlatformFontDatabase::fontDir() const |
357 | { |
358 | QString fontpath = QString::fromLocal8Bit(qgetenv("QT_QPA_FONTDIR" )); |
359 | if (fontpath.isEmpty()) |
360 | fontpath = QLibraryInfo::path(QLibraryInfo::LibrariesPath) + QLatin1String("/fonts" ); |
361 | |
362 | return fontpath; |
363 | } |
364 | |
365 | /*! |
366 | Returns true if the font family is private. For any given family name, |
367 | the result is platform dependent. |
368 | */ |
369 | bool QPlatformFontDatabase::isPrivateFontFamily(const QString &family) const |
370 | { |
371 | Q_UNUSED(family); |
372 | return false; |
373 | } |
374 | |
375 | /*! |
376 | Returns the default system font. |
377 | |
378 | \sa QGuiApplication::font() |
379 | \since 5.0 |
380 | */ |
381 | |
382 | QFont QPlatformFontDatabase::defaultFont() const |
383 | { |
384 | return QFont(QLatin1String("Helvetica" )); |
385 | } |
386 | |
387 | |
388 | QString qt_resolveFontFamilyAlias(const QString &alias); |
389 | |
390 | /*! |
391 | Resolve alias to actual font family names. |
392 | |
393 | \since 5.0 |
394 | */ |
395 | QString QPlatformFontDatabase::resolveFontFamilyAlias(const QString &family) const |
396 | { |
397 | return qt_resolveFontFamilyAlias(family); |
398 | } |
399 | |
400 | /*! |
401 | Return true if all fonts are considered scalable when using this font database. |
402 | Defaults to false. |
403 | |
404 | \since 5.0 |
405 | */ |
406 | |
407 | bool QPlatformFontDatabase::fontsAlwaysScalable() const |
408 | { |
409 | return false; |
410 | } |
411 | |
412 | /*! |
413 | Return list of standard font sizes when using this font database. |
414 | |
415 | \since 5.0 |
416 | */ |
417 | |
418 | QList<int> QPlatformFontDatabase::standardSizes() const |
419 | { |
420 | QList<int> ret; |
421 | static const quint8 standard[] = |
422 | { 6, 7, 8, 9, 10, 11, 12, 14, 16, 18, 20, 22, 24, 26, 28, 36, 48, 72 }; |
423 | static const int num_standards = int(sizeof standard / sizeof *standard); |
424 | ret.reserve(num_standards); |
425 | std::copy(standard, standard + num_standards, std::back_inserter(ret)); |
426 | return ret; |
427 | } |
428 | |
429 | // see the Unicode subset bitfields in the MSDN docs |
430 | static const quint8 requiredUnicodeBits[QFontDatabase::WritingSystemsCount][2] = { |
431 | { 127, 127 }, // Any |
432 | { 0, 127 }, // Latin |
433 | { 7, 127 }, // Greek |
434 | { 9, 127 }, // Cyrillic |
435 | { 10, 127 }, // Armenian |
436 | { 11, 127 }, // Hebrew |
437 | { 13, 127 }, // Arabic |
438 | { 71, 127 }, // Syriac |
439 | { 72, 127 }, // Thaana |
440 | { 15, 127 }, // Devanagari |
441 | { 16, 127 }, // Bengali |
442 | { 17, 127 }, // Gurmukhi |
443 | { 18, 127 }, // Gujarati |
444 | { 19, 127 }, // Oriya |
445 | { 20, 127 }, // Tamil |
446 | { 21, 127 }, // Telugu |
447 | { 22, 127 }, // Kannada |
448 | { 23, 127 }, // Malayalam |
449 | { 73, 127 }, // Sinhala |
450 | { 24, 127 }, // Thai |
451 | { 25, 127 }, // Lao |
452 | { 70, 127 }, // Tibetan |
453 | { 74, 127 }, // Myanmar |
454 | { 26, 127 }, // Georgian |
455 | { 80, 127 }, // Khmer |
456 | { 126, 127 }, // SimplifiedChinese |
457 | { 126, 127 }, // TraditionalChinese |
458 | { 126, 127 }, // Japanese |
459 | { 56, 127 }, // Korean |
460 | { 0, 127 }, // Vietnamese (same as latin1) |
461 | { 126, 127 }, // Other |
462 | { 78, 127 }, // Ogham |
463 | { 79, 127 }, // Runic |
464 | { 14, 127 }, // Nko |
465 | }; |
466 | |
467 | enum CsbBits { |
468 | Latin1CsbBit = 0, |
469 | CentralEuropeCsbBit = 1, |
470 | TurkishCsbBit = 4, |
471 | BalticCsbBit = 7, |
472 | CyrillicCsbBit = 2, |
473 | GreekCsbBit = 3, |
474 | HebrewCsbBit = 5, |
475 | ArabicCsbBit = 6, |
476 | VietnameseCsbBit = 8, |
477 | SimplifiedChineseCsbBit = 18, |
478 | TraditionalChineseCsbBit = 20, |
479 | ThaiCsbBit = 16, |
480 | JapaneseCsbBit = 17, |
481 | KoreanCsbBit = 19, |
482 | KoreanJohabCsbBit = 21, |
483 | SymbolCsbBit = 31 |
484 | }; |
485 | |
486 | /*! |
487 | Helper function that determines the writing system support based on the contents of the OS/2 table |
488 | in the font. |
489 | |
490 | \since 6.0 |
491 | */ |
492 | QSupportedWritingSystems QPlatformFontDatabase::writingSystemsFromOS2Table(const char *os2Table, size_t length) |
493 | { |
494 | if (length >= 86) { |
495 | quint32 unicodeRange[4] = { |
496 | qFromBigEndian<quint32>(os2Table + 42), |
497 | qFromBigEndian<quint32>(os2Table + 46), |
498 | qFromBigEndian<quint32>(os2Table + 50), |
499 | qFromBigEndian<quint32>(os2Table + 54) |
500 | }; |
501 | quint32 [2] = { |
502 | qFromBigEndian<quint32>(os2Table + 78), |
503 | qFromBigEndian<quint32>(os2Table + 82) |
504 | }; |
505 | |
506 | return writingSystemsFromTrueTypeBits(unicodeRange, codePageRange); |
507 | } |
508 | |
509 | return QSupportedWritingSystems(); |
510 | } |
511 | |
512 | /*! |
513 | Helper function that determines the writing systems support by a given |
514 | \a unicodeRange and \a codePageRange. |
515 | |
516 | \since 5.1 |
517 | */ |
518 | QSupportedWritingSystems QPlatformFontDatabase::writingSystemsFromTrueTypeBits(quint32 unicodeRange[4], quint32 [2]) |
519 | { |
520 | QSupportedWritingSystems writingSystems; |
521 | |
522 | bool hasScript = false; |
523 | for (int i = 0; i < QFontDatabase::WritingSystemsCount; ++i) { |
524 | int bit = requiredUnicodeBits[i][0]; |
525 | int index = bit/32; |
526 | int flag = 1 << (bit&31); |
527 | if (bit != 126 && (unicodeRange[index] & flag)) { |
528 | bit = requiredUnicodeBits[i][1]; |
529 | index = bit/32; |
530 | |
531 | flag = 1 << (bit&31); |
532 | if (bit == 127 || (unicodeRange[index] & flag)) { |
533 | writingSystems.setSupported(QFontDatabase::WritingSystem(i)); |
534 | hasScript = true; |
535 | // qDebug("font %s: index=%d, flag=%8x supports script %d", familyName.latin1(), index, flag, i); |
536 | } |
537 | } |
538 | } |
539 | if (codePageRange[0] & ((1 << Latin1CsbBit) | (1 << CentralEuropeCsbBit) | (1 << TurkishCsbBit) | (1 << BalticCsbBit))) { |
540 | writingSystems.setSupported(QFontDatabase::Latin); |
541 | hasScript = true; |
542 | //qDebug("font %s supports Latin", familyName.latin1()); |
543 | } |
544 | if (codePageRange[0] & (1 << CyrillicCsbBit)) { |
545 | writingSystems.setSupported(QFontDatabase::Cyrillic); |
546 | hasScript = true; |
547 | //qDebug("font %s supports Cyrillic", familyName.latin1()); |
548 | } |
549 | if (codePageRange[0] & (1 << GreekCsbBit)) { |
550 | writingSystems.setSupported(QFontDatabase::Greek); |
551 | hasScript = true; |
552 | //qDebug("font %s supports Greek", familyName.latin1()); |
553 | } |
554 | if (codePageRange[0] & (1 << HebrewCsbBit)) { |
555 | writingSystems.setSupported(QFontDatabase::Hebrew); |
556 | hasScript = true; |
557 | //qDebug("font %s supports Hebrew", familyName.latin1()); |
558 | } |
559 | if (codePageRange[0] & (1 << ArabicCsbBit)) { |
560 | writingSystems.setSupported(QFontDatabase::Arabic); |
561 | hasScript = true; |
562 | //qDebug("font %s supports Arabic", familyName.latin1()); |
563 | } |
564 | if (codePageRange[0] & (1 << ThaiCsbBit)) { |
565 | writingSystems.setSupported(QFontDatabase::Thai); |
566 | hasScript = true; |
567 | //qDebug("font %s supports Thai", familyName.latin1()); |
568 | } |
569 | if (codePageRange[0] & (1 << VietnameseCsbBit)) { |
570 | writingSystems.setSupported(QFontDatabase::Vietnamese); |
571 | hasScript = true; |
572 | //qDebug("font %s supports Vietnamese", familyName.latin1()); |
573 | } |
574 | if (codePageRange[0] & (1 << SimplifiedChineseCsbBit)) { |
575 | writingSystems.setSupported(QFontDatabase::SimplifiedChinese); |
576 | hasScript = true; |
577 | //qDebug("font %s supports Simplified Chinese", familyName.latin1()); |
578 | } |
579 | if (codePageRange[0] & (1 << TraditionalChineseCsbBit)) { |
580 | writingSystems.setSupported(QFontDatabase::TraditionalChinese); |
581 | hasScript = true; |
582 | //qDebug("font %s supports Traditional Chinese", familyName.latin1()); |
583 | } |
584 | if (codePageRange[0] & (1 << JapaneseCsbBit)) { |
585 | writingSystems.setSupported(QFontDatabase::Japanese); |
586 | hasScript = true; |
587 | //qDebug("font %s supports Japanese", familyName.latin1()); |
588 | } |
589 | if (codePageRange[0] & ((1 << KoreanCsbBit) | (1 << KoreanJohabCsbBit))) { |
590 | writingSystems.setSupported(QFontDatabase::Korean); |
591 | hasScript = true; |
592 | //qDebug("font %s supports Korean", familyName.latin1()); |
593 | } |
594 | if (codePageRange[0] & (1U << SymbolCsbBit)) { |
595 | writingSystems = QSupportedWritingSystems(); |
596 | hasScript = false; |
597 | } |
598 | |
599 | if (!hasScript) |
600 | writingSystems.setSupported(QFontDatabase::Symbol); |
601 | |
602 | return writingSystems; |
603 | } |
604 | |
605 | /*! |
606 | Helper function that register the \a alias for the \a familyName. |
607 | |
608 | \since 5.2 |
609 | */ |
610 | |
611 | void QPlatformFontDatabase::registerAliasToFontFamily(const QString &familyName, const QString &alias) |
612 | { |
613 | qt_registerAliasToFontFamily(familyName, alias); |
614 | } |
615 | |
616 | /*! |
617 | Helper function that returns true if the font family has already been registered and populated. |
618 | |
619 | \since 5.14 |
620 | */ |
621 | bool QPlatformFontDatabase::isFamilyPopulated(const QString &familyName) |
622 | { |
623 | return qt_isFontFamilyPopulated(familyName); |
624 | } |
625 | |
626 | /*! |
627 | \class QPlatformFontDatabase |
628 | \since 5.0 |
629 | \internal |
630 | \preliminary |
631 | \ingroup qpa |
632 | \ingroup painting |
633 | |
634 | \brief The QPlatformFontDatabase class makes it possible to customize how fonts |
635 | are discovered and how they are rendered |
636 | |
637 | QPlatformFontDatabase is the superclass which is intended to let platform implementations use |
638 | native font handling. |
639 | |
640 | Qt has its internal font database which it uses to discover available fonts on the |
641 | user's system. To be able to populate this database subclass this class, and |
642 | reimplement populateFontDatabase(). |
643 | |
644 | Use the function registerFont() to populate the internal font database. |
645 | |
646 | Sometimes a specified font does not have the required glyphs; in such a case, the |
647 | fallbackForFamily() function is called automatically to find alternative font |
648 | families that can supply alternatives to the missing glyphs. |
649 | |
650 | \sa QSupportedWritingSystems |
651 | */ |
652 | QT_END_NAMESPACE |
653 | |