-
Notifications
You must be signed in to change notification settings - Fork 1k
/
qfont.cpp
3347 lines (2731 loc) · 99.8 KB
/
qfont.cpp
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/****************************************************************************
**
** Copyright (C) 2019 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the QtGui module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 3 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL3 included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 3 requirements
** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or (at your option) the GNU General
** Public license version 3 or any later version approved by the KDE Free
** Qt Foundation. The licenses are as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-2.0.html and
** https://www.gnu.org/licenses/gpl-3.0.html.
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include "qfont.h"
#include "qdebug.h"
#include "qpaintdevice.h"
#include "qfontdatabase.h"
#include "qfontmetrics.h"
#include "qfontinfo.h"
#include "qpainter.h"
#include "qhash.h"
#include "qdatastream.h"
#include "qguiapplication.h"
#include "qstringlist.h"
#include "qscreen.h"
#include "qthread.h"
#include "qthreadstorage.h"
#include "qfont_p.h"
#include <private/qfontengine_p.h>
#include <private/qpainter_p.h>
#include <private/qtextengine_p.h>
#include <limits.h>
#include <qpa/qplatformscreen.h>
#include <qpa/qplatformintegration.h>
#include <qpa/qplatformfontdatabase.h>
#include <QtGui/private/qguiapplication_p.h>
#include <QtCore/QMutexLocker>
#include <QtCore/QMutex>
// #define QFONTCACHE_DEBUG
#ifdef QFONTCACHE_DEBUG
# define FC_DEBUG qDebug
#else
# define FC_DEBUG if (false) qDebug
#endif
QT_BEGIN_NAMESPACE
#ifndef QFONTCACHE_DECREASE_TRIGGER_LIMIT
# define QFONTCACHE_DECREASE_TRIGGER_LIMIT 256
#endif
bool QFontDef::exactMatch(const QFontDef &other) const
{
/*
QFontDef comparison is more complicated than just simple
per-member comparisons.
When comparing point/pixel sizes, either point or pixelsize
could be -1. in This case we have to compare the non negative
size value.
This test will fail if the point-sizes differ by 1/2 point or
more or they do not round to the same value. We have to do this
since our API still uses 'int' point-sizes in the API, but store
deci-point-sizes internally.
To compare the family members, we need to parse the font names
and compare the family/foundry strings separately. This allows
us to compare e.g. "Helvetica" and "Helvetica [Adobe]" with
positive results.
*/
if (pixelSize != -1 && other.pixelSize != -1) {
if (pixelSize != other.pixelSize)
return false;
} else if (pointSize != -1 && other.pointSize != -1) {
if (pointSize != other.pointSize)
return false;
} else {
return false;
}
if (!ignorePitch && !other.ignorePitch && fixedPitch != other.fixedPitch)
return false;
if (stretch != 0 && other.stretch != 0 && stretch != other.stretch)
return false;
QString this_family, this_foundry, other_family, other_foundry;
for (int i = 0; i < families.size(); ++i) {
QFontDatabasePrivate::parseFontName(families.at(i), this_foundry, this_family);
QFontDatabasePrivate::parseFontName(other.families.at(i), other_foundry, other_family);
if (this_family != other_family || this_foundry != other_foundry)
return false;
}
return (styleHint == other.styleHint
&& styleStrategy == other.styleStrategy
&& weight == other.weight
&& style == other.style
&& this_family == other_family
&& (styleName.isEmpty() || other.styleName.isEmpty() || styleName == other.styleName)
&& (this_foundry.isEmpty()
|| other_foundry.isEmpty()
|| this_foundry == other_foundry)
);
}
extern bool qt_is_gui_used;
Q_GUI_EXPORT int qt_defaultDpiX()
{
if (QCoreApplication::instance()->testAttribute(Qt::AA_Use96Dpi))
return 96;
if (!qt_is_gui_used)
return 75;
if (const QScreen *screen = QGuiApplication::primaryScreen())
return qRound(screen->logicalDotsPerInchX());
//PI has not been initialised, or it is being initialised. Give a default dpi
return 100;
}
Q_GUI_EXPORT int qt_defaultDpiY()
{
if (QCoreApplication::instance()->testAttribute(Qt::AA_Use96Dpi))
return 96;
if (!qt_is_gui_used)
return 75;
if (const QScreen *screen = QGuiApplication::primaryScreen())
return qRound(screen->logicalDotsPerInchY());
//PI has not been initialised, or it is being initialised. Give a default dpi
return 100;
}
Q_GUI_EXPORT int qt_defaultDpi()
{
return qt_defaultDpiY();
}
/* Helper function to convert between legacy Qt and OpenType font weights. */
static int convertWeights(int weight, bool inverted)
{
static const QVarLengthArray<QPair<int, int>, 9> legacyToOpenTypeMap = {
{ 0, QFont::Thin }, { 12, QFont::ExtraLight }, { 25, QFont::Light },
{ 50, QFont::Normal }, { 57, QFont::Medium }, { 63, QFont::DemiBold },
{ 75, QFont::Bold }, { 81, QFont::ExtraBold }, { 87, QFont::Black },
};
int closestDist = INT_MAX;
int result = -1;
// Go through and find the closest mapped value
for (auto mapping : legacyToOpenTypeMap) {
const int weightOld = inverted ? mapping.second : mapping.first;
const int weightNew = inverted ? mapping.first : mapping.second;
const int dist = qAbs(weightOld - weight);
if (dist < closestDist) {
result = weightNew;
closestDist = dist;
} else {
// Break early since following values will be further away
break;
}
}
return result;
}
// Splits the family string on a comma and returns the list based on that
static QStringList splitIntoFamilies(const QString &family)
{
QStringList familyList;
if (family.isEmpty())
return familyList;
const auto list = QStringView{family}.split(QLatin1Char(','));
const int numFamilies = list.size();
familyList.reserve(numFamilies);
for (int i = 0; i < numFamilies; ++i) {
auto str = list.at(i).trimmed();
if ((str.startsWith(QLatin1Char('"')) && str.endsWith(QLatin1Char('"')))
|| (str.startsWith(QLatin1Char('\'')) && str.endsWith(QLatin1Char('\'')))) {
str = str.mid(1, str.length() - 2);
}
familyList << str.toString();
}
return familyList;
}
/* Converts from legacy Qt font weight (Qt < 6.0) to OpenType font weight (Qt >= 6.0) */
Q_GUI_EXPORT int qt_legacyToOpenTypeWeight(int weight)
{
return convertWeights(weight, false);
}
/* Converts from OpenType font weight (Qt >= 6.0) to legacy Qt font weight (Qt < 6.0) */
Q_GUI_EXPORT int qt_openTypeToLegacyWeight(int weight)
{
return convertWeights(weight, true);
}
QFontPrivate::QFontPrivate()
: engineData(nullptr), dpi(qt_defaultDpi()),
underline(false), overline(false), strikeOut(false), kerning(true),
capital(0), letterSpacingIsAbsolute(false), scFont(nullptr)
{
}
QFontPrivate::QFontPrivate(const QFontPrivate &other)
: request(other.request), engineData(nullptr), dpi(other.dpi),
underline(other.underline), overline(other.overline),
strikeOut(other.strikeOut), kerning(other.kerning),
capital(other.capital), letterSpacingIsAbsolute(other.letterSpacingIsAbsolute),
letterSpacing(other.letterSpacing), wordSpacing(other.wordSpacing),
scFont(other.scFont)
{
if (scFont && scFont != this)
scFont->ref.ref();
}
QFontPrivate::~QFontPrivate()
{
if (engineData && !engineData->ref.deref())
delete engineData;
engineData = nullptr;
if (scFont && scFont != this)
scFont->ref.deref();
scFont = nullptr;
}
extern QRecursiveMutex *qt_fontdatabase_mutex();
#define QT_FONT_ENGINE_FROM_DATA(data, script) data->engines[script]
QFontEngine *QFontPrivate::engineForScript(int script) const
{
QMutexLocker locker(qt_fontdatabase_mutex());
if (script <= QChar::Script_Latin)
script = QChar::Script_Common;
if (engineData && engineData->fontCacheId != QFontCache::instance()->id()) {
// throw out engineData that came from a different thread
if (!engineData->ref.deref())
delete engineData;
engineData = nullptr;
}
if (!engineData || !QT_FONT_ENGINE_FROM_DATA(engineData, script))
QFontDatabasePrivate::load(this, script);
return QT_FONT_ENGINE_FROM_DATA(engineData, script);
}
void QFontPrivate::alterCharForCapitalization(QChar &c) const {
switch (capital) {
case QFont::AllUppercase:
case QFont::SmallCaps:
c = c.toUpper();
break;
case QFont::AllLowercase:
c = c.toLower();
break;
case QFont::MixedCase:
break;
}
}
QFontPrivate *QFontPrivate::smallCapsFontPrivate() const
{
if (scFont)
return scFont;
QFont font(const_cast<QFontPrivate *>(this));
qreal pointSize = font.pointSizeF();
if (pointSize > 0)
font.setPointSizeF(pointSize * .7);
else
font.setPixelSize((font.pixelSize() * 7 + 5) / 10);
scFont = font.d.data();
if (scFont != this)
scFont->ref.ref();
return scFont;
}
void QFontPrivate::resolve(uint mask, const QFontPrivate *other)
{
Q_ASSERT(other != nullptr);
dpi = other->dpi;
if ((mask & QFont::AllPropertiesResolved) == QFont::AllPropertiesResolved) return;
// assign the unset-bits with the set-bits of the other font def
if (!(mask & QFont::FamiliesResolved))
request.families = other->request.families;
if (! (mask & QFont::StyleNameResolved))
request.styleName = other->request.styleName;
if (! (mask & QFont::SizeResolved)) {
request.pointSize = other->request.pointSize;
request.pixelSize = other->request.pixelSize;
}
if (! (mask & QFont::StyleHintResolved))
request.styleHint = other->request.styleHint;
if (! (mask & QFont::StyleStrategyResolved))
request.styleStrategy = other->request.styleStrategy;
if (! (mask & QFont::WeightResolved))
request.weight = other->request.weight;
if (! (mask & QFont::StyleResolved))
request.style = other->request.style;
if (! (mask & QFont::FixedPitchResolved))
request.fixedPitch = other->request.fixedPitch;
if (! (mask & QFont::StretchResolved))
request.stretch = other->request.stretch;
if (! (mask & QFont::HintingPreferenceResolved))
request.hintingPreference = other->request.hintingPreference;
if (! (mask & QFont::UnderlineResolved))
underline = other->underline;
if (! (mask & QFont::OverlineResolved))
overline = other->overline;
if (! (mask & QFont::StrikeOutResolved))
strikeOut = other->strikeOut;
if (! (mask & QFont::KerningResolved))
kerning = other->kerning;
if (! (mask & QFont::LetterSpacingResolved)) {
letterSpacing = other->letterSpacing;
letterSpacingIsAbsolute = other->letterSpacingIsAbsolute;
}
if (! (mask & QFont::WordSpacingResolved))
wordSpacing = other->wordSpacing;
if (! (mask & QFont::CapitalizationResolved))
capital = other->capital;
}
QFontEngineData::QFontEngineData()
: ref(0), fontCacheId(QFontCache::instance()->id())
{
memset(engines, 0, QChar::ScriptCount * sizeof(QFontEngine *));
}
QFontEngineData::~QFontEngineData()
{
Q_ASSERT(ref.loadRelaxed() == 0);
for (int i = 0; i < QChar::ScriptCount; ++i) {
if (engines[i]) {
if (!engines[i]->ref.deref())
delete engines[i];
engines[i] = nullptr;
}
}
}
/*!
\class QFont
\reentrant
\brief The QFont class specifies a query for a font used for drawing text.
\ingroup painting
\ingroup appearance
\ingroup shared
\ingroup richtext-processing
\inmodule QtGui
QFont can be regarded as a query for one or more fonts on the system.
When you create a QFont object you specify various attributes that
you want the font to have. Qt will use the font with the specified
attributes, or if no matching font exists, Qt will use the closest
matching installed font. The attributes of the font that is
actually used are retrievable from a QFontInfo object. If the
window system provides an exact match exactMatch() returns \c true.
Use QFontMetricsF to get measurements, e.g. the pixel length of a
string using QFontMetrics::width().
Attributes which are not specifically set will not affect the font
selection algorithm, and default values will be preferred instead.
To load a specific physical font, typically represented by a single file,
use QRawFont instead.
Note that a QGuiApplication instance must exist before a QFont can be
used. You can set the application's default font with
QGuiApplication::setFont().
If a chosen font does not include all the characters that
need to be displayed, QFont will try to find the characters in the
nearest equivalent fonts. When a QPainter draws a character from a
font the QFont will report whether or not it has the character; if
it does not, QPainter will draw an unfilled square.
Create QFonts like this:
\snippet code/src_gui_text_qfont.cpp 0
The attributes set in the constructor can also be set later, e.g.
setFamily(), setPointSize(), setPointSizeF(), setWeight() and
setItalic(). The remaining attributes must be set after
contstruction, e.g. setBold(), setUnderline(), setOverline(),
setStrikeOut() and setFixedPitch(). QFontInfo objects should be
created \e after the font's attributes have been set. A QFontInfo
object will not change, even if you change the font's
attributes. The corresponding "get" functions, e.g. family(),
pointSize(), etc., return the values that were set, even though
the values used may differ. The actual values are available from a
QFontInfo object.
If the requested font family is unavailable you can influence the
\l{#fontmatching}{font matching algorithm} by choosing a
particular \l{QFont::StyleHint} and \l{QFont::StyleStrategy} with
setStyleHint(). The default family (corresponding to the current
style hint) is returned by defaultFamily().
You can provide substitutions for font family names using
insertSubstitution() and insertSubstitutions(). Substitutions can
be removed with removeSubstitutions(). Use substitute() to retrieve
a family's first substitute, or the family name itself if it has
no substitutes. Use substitutes() to retrieve a list of a family's
substitutes (which may be empty). After substituting a font, you must
trigger the updating of the font by destroying and re-creating all
QFont objects.
Every QFont has a key() which you can use, for example, as the key
in a cache or dictionary. If you want to store a user's font
preferences you could use QSettings, writing the font information
with toString() and reading it back with fromString(). The
operator<<() and operator>>() functions are also available, but
they work on a data stream.
It is possible to set the height of characters shown on the screen
to a specified number of pixels with setPixelSize(); however using
setPointSize() has a similar effect and provides device
independence.
Loading fonts can be expensive, especially on X11. QFont contains
extensive optimizations to make the copying of QFont objects fast,
and to cache the results of the slow window system functions it
depends upon.
\target fontmatching
The font matching algorithm works as follows:
\list 1
\li The specified font families (set by setFamilies()) are searched for.
\li If not found, then if set the specified font family exists and can be used to represent
the writing system in use, it will be selected.
\li If not, a replacement font that supports the writing system is
selected. The font matching algorithm will try to find the
best match for all the properties set in the QFont. How this is
done varies from platform to platform.
\li If no font exists on the system that can support the text,
then special "missing character" boxes will be shown in its place.
\endlist
\note If the selected font, though supporting the writing system in general,
is missing glyphs for one or more specific characters, then Qt will try to
find a fallback font for this or these particular characters. This feature
can be disabled using QFont::NoFontMerging style strategy.
In Windows a request for the "Courier" font is automatically changed to
"Courier New", an improved version of Courier that allows for smooth scaling.
The older "Courier" bitmap font can be selected by setting the PreferBitmap
style strategy (see setStyleStrategy()).
Once a font is found, the remaining attributes are matched in order of
priority:
\list 1
\li fixedPitch()
\li pointSize() (see below)
\li weight()
\li style()
\endlist
If you have a font which matches on family, even if none of the
other attributes match, this font will be chosen in preference to
a font which doesn't match on family but which does match on the
other attributes. This is because font family is the dominant
search criteria.
The point size is defined to match if it is within 20% of the
requested point size. When several fonts match and are only
distinguished by point size, the font with the closest point size
to the one requested will be chosen.
The actual family, font size, weight and other font attributes
used for drawing text will depend on what's available for the
chosen family under the window system. A QFontInfo object can be
used to determine the actual values used for drawing the text.
Examples:
\snippet code/src_gui_text_qfont.cpp 1
If you had both an Adobe and a Cronyx Helvetica, you might get
either.
\snippet code/src_gui_text_qfont.cpp 2
You can specify the foundry you want in the family name. The font f
in the above example will be set to "Helvetica
[Cronyx]".
To determine the attributes of the font actually used in the window
system, use a QFontInfo object, e.g.
\snippet code/src_gui_text_qfont.cpp 3
To find out font metrics use a QFontMetrics object, e.g.
\snippet code/src_gui_text_qfont.cpp 4
For more general information on fonts, see the
\l{comp.fonts FAQ}{comp.fonts FAQ}.
Information on encodings can be found from
\l{Roman Czyborra's} page.
\sa QFontMetrics, QFontInfo, QFontDatabase, {Character Map Example}
*/
/*!
\internal
\enum QFont::ResolveProperties
This enum describes the properties of a QFont that can be set on a font
individually and then considered resolved.
\value FamilyResolved
\value FamiliesResolved
\value SizeResolved
\value StyleHintResolved
\value StyleStrategyResolved
\value WeightResolved
\value StyleResolved
\value UnderlineResolved
\value OverlineResolved
\value StrikeOutResolved
\value FixedPitchResolved
\value StretchResolved
\value KerningResolved
\value CapitalizationResolved
\value LetterSpacingResolved
\value WordSpacingResolved
\value CompletelyResolved
*/
/*!
\enum QFont::Style
This enum describes the different styles of glyphs that are used to
display text.
\value StyleNormal Normal glyphs used in unstyled text.
\value StyleItalic Italic glyphs that are specifically designed for
the purpose of representing italicized text.
\value StyleOblique Glyphs with an italic appearance that are typically
based on the unstyled glyphs, but are not fine-tuned
for the purpose of representing italicized text.
\sa Weight
*/
/*!
\fn QFont &QFont::operator=(QFont &&other)
Move-assigns \a other to this QFont instance.
\since 5.2
*/
#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
/*
\obsolete
Constructs a font from \a font for use on the paint device \a pd.
*/
QFont::QFont(const QFont &font, QPaintDevice *pd)
: QFont(font, static_cast<const QPaintDevice*>(pd))
{}
#endif
/*!
\since 5.13
Constructs a font from \a font for use on the paint device \a pd.
*/
QFont::QFont(const QFont &font, const QPaintDevice *pd)
: resolve_mask(font.resolve_mask)
{
Q_ASSERT(pd);
const int dpi = pd->logicalDpiY();
if (font.d->dpi != dpi) {
d = new QFontPrivate(*font.d);
d->dpi = dpi;
} else {
d = font.d;
}
}
/*!
\internal
*/
QFont::QFont(QFontPrivate *data)
: d(data), resolve_mask(QFont::AllPropertiesResolved)
{
}
/*! \internal
Detaches the font object from common font data.
*/
void QFont::detach()
{
if (d->ref.loadRelaxed() == 1) {
if (d->engineData && !d->engineData->ref.deref())
delete d->engineData;
d->engineData = nullptr;
if (d->scFont && d->scFont != d.data())
d->scFont->ref.deref();
d->scFont = nullptr;
return;
}
d.detach();
}
/*!
\internal
Detaches the font object from common font attributes data.
Call this instead of QFont::detach() if the only font attributes data
has been changed (underline, letterSpacing, kerning, etc.).
*/
void QFontPrivate::detachButKeepEngineData(QFont *font)
{
if (font->d->ref.loadRelaxed() == 1)
return;
QFontEngineData *engineData = font->d->engineData;
if (engineData)
engineData->ref.ref();
font->d.detach();
font->d->engineData = engineData;
}
/*!
Constructs a font object that uses the application's default font.
\sa QGuiApplication::setFont(), QGuiApplication::font()
*/
QFont::QFont()
: d(QGuiApplicationPrivate::instance() ? QGuiApplication::font().d.data() : new QFontPrivate()), resolve_mask(0)
{
}
/*!
\obsolete
Constructs a font object with the specified \a family, \a
pointSize, \a weight and \a italic settings.
If \a pointSize is zero or negative, the point size of the font
is set to a system-dependent default value. Generally, this is
12 points.
The \a family name may optionally also include a foundry name,
e.g. "Helvetica [Cronyx]". If the \a family is
available from more than one foundry and the foundry isn't
specified, an arbitrary foundry is chosen. If the family isn't
available a family will be set using the \l{QFont}{font matching}
algorithm.
This will split the family string on a comma and call setFamilies() with the
resulting list. To preserve a font that uses a comma in its name, use
the constructor that takes a QStringList.
\sa Weight, setFamily(), setPointSize(), setWeight(), setItalic(),
setStyleHint(), setFamilies(), QGuiApplication::font()
*/
QFont::QFont(const QString &family, int pointSize, int weight, bool italic)
: d(new QFontPrivate()), resolve_mask(QFont::FamiliesResolved)
{
if (pointSize <= 0) {
pointSize = 12;
} else {
resolve_mask |= QFont::SizeResolved;
}
if (weight < 0) {
weight = Normal;
} else {
resolve_mask |= QFont::WeightResolved | QFont::StyleResolved;
}
if (italic)
resolve_mask |= QFont::StyleResolved;
d->request.families = splitIntoFamilies(family);
d->request.pointSize = qreal(pointSize);
d->request.pixelSize = -1;
d->request.weight = weight;
d->request.style = italic ? QFont::StyleItalic : QFont::StyleNormal;
}
/*!
Constructs a font object with the specified \a families, \a
pointSize, \a weight and \a italic settings.
If \a pointSize is zero or negative, the point size of the font
is set to a system-dependent default value. Generally, this is
12 points.
Each family name entry in \a families may optionally also include
a foundry name, e.g. "Helvetica [Cronyx]". If the family is
available from more than one foundry and the foundry isn't
specified, an arbitrary foundry is chosen. If the family isn't
available a family will be set using the \l{QFont}{font matching}
algorithm.
\sa Weight, setPointSize(), setWeight(), setItalic(),
setStyleHint(), setFamilies(), QGuiApplication::font()
*/
QFont::QFont(const QStringList &families, int pointSize, int weight, bool italic)
: d(new QFontPrivate()), resolve_mask(QFont::FamiliesResolved)
{
if (pointSize <= 0)
pointSize = 12;
else
resolve_mask |= QFont::SizeResolved;
if (weight < 0)
weight = Normal;
else
resolve_mask |= QFont::WeightResolved | QFont::StyleResolved;
if (italic)
resolve_mask |= QFont::StyleResolved;
d->request.families = families;
d->request.pointSize = qreal(pointSize);
d->request.pixelSize = -1;
d->request.weight = weight;
d->request.style = italic ? QFont::StyleItalic : QFont::StyleNormal;
}
/*!
Constructs a font that is a copy of \a font.
*/
QFont::QFont(const QFont &font)
: d(font.d), resolve_mask(font.resolve_mask)
{
}
/*!
Destroys the font object and frees all allocated resources.
*/
QFont::~QFont()
{
}
/*!
Assigns \a font to this font and returns a reference to it.
*/
QFont &QFont::operator=(const QFont &font)
{
d = font.d;
resolve_mask = font.resolve_mask;
return *this;
}
/*!
\fn void QFont::swap(QFont &other)
\since 5.0
Swaps this font instance with \a other. This function is very fast
and never fails.
*/
/*!
Returns the requested font family name. This will always be the same
as the first entry in the families() call.
\sa setFamily(), substitutes(), substitute(), setFamilies(), families()
*/
QString QFont::family() const
{
return d->request.families.isEmpty() ? QString() : d->request.families.first();
}
/*!
Sets the family name of the font. The name is case insensitive and
may include a foundry name.
The \a family name may optionally also include a foundry name,
e.g. "Helvetica [Cronyx]". If the \a family is
available from more than one foundry and the foundry isn't
specified, an arbitrary foundry is chosen. If the family isn't
available a family will be set using the \l{QFont}{font matching}
algorithm.
This will split the family string on a comma and call setFamilies() with the
resulting list. To preserve a font that uses a comma in it's name then use
setFamilies() directly. From Qt 6.2 this behavior will no longer happen and
\a family will be passed as a single family.
\sa family(), setStyleHint(), setFamilies(), families(), QFontInfo
*/
void QFont::setFamily(const QString &family)
{
#ifdef QT_DEBUG
if (family.contains(QLatin1Char(','))) {
qWarning("From Qt 6.2, QFont::setFamily() will no long split the family string on the comma"
" and will keep it as a single family");
}
#endif
setFamilies(splitIntoFamilies(family));
}
/*!
\since 4.8
Returns the requested font style name. This can be used to match the
font with irregular styles (that can't be normalized in other style
properties).
\sa setFamily(), setStyle()
*/
QString QFont::styleName() const
{
return d->request.styleName;
}
/*!
\since 4.8
Sets the style name of the font to \a styleName. When set, other style properties
like \l style() and \l weight() will be ignored for font matching, though they may be
simulated afterwards if supported by the platform's font engine.
Due to the lower quality of artificially simulated styles, and the lack of full cross
platform support, it is not recommended to use matching by style name together with
matching by style properties
\sa styleName()
*/
void QFont::setStyleName(const QString &styleName)
{
if ((resolve_mask & QFont::StyleNameResolved) && d->request.styleName == styleName)
return;
detach();
d->request.styleName = styleName;
resolve_mask |= QFont::StyleNameResolved;
}
/*!
Returns the point size of the font. Returns -1 if the font size
was specified in pixels.
\sa setPointSize(), pointSizeF()
*/
int QFont::pointSize() const
{
return qRound(d->request.pointSize);
}
/*!
\since 4.8
\enum QFont::HintingPreference
This enum describes the different levels of hinting that can be applied
to glyphs to improve legibility on displays where it might be warranted
by the density of pixels.
\value PreferDefaultHinting Use the default hinting level for the target platform.
\value PreferNoHinting If possible, render text without hinting the outlines
of the glyphs. The text layout will be typographically accurate and
scalable, using the same metrics as are used e.g. when printing.
\value PreferVerticalHinting If possible, render text with no horizontal hinting,
but align glyphs to the pixel grid in the vertical direction. The text will appear
crisper on displays where the density is too low to give an accurate rendering
of the glyphs. But since the horizontal metrics of the glyphs are unhinted, the text's
layout will be scalable to higher density devices (such as printers) without impacting
details such as line breaks.
\value PreferFullHinting If possible, render text with hinting in both horizontal and
vertical directions. The text will be altered to optimize legibility on the target
device, but since the metrics will depend on the target size of the text, the positions
of glyphs, line breaks, and other typographical detail will not scale, meaning that a
text layout may look different on devices with different pixel densities.
Please note that this enum only describes a preference, as the full range of hinting levels
are not supported on all of Qt's supported platforms. The following table details the effect
of a given hinting preference on a selected set of target platforms.
\table
\header
\li
\li PreferDefaultHinting
\li PreferNoHinting
\li PreferVerticalHinting
\li PreferFullHinting
\row
\li Windows Vista (w/o Platform Update) and earlier
\li Full hinting
\li Full hinting
\li Full hinting
\li Full hinting
\row
\li Windows 7 and Windows Vista (w/Platform Update) and DirectWrite enabled in Qt
\li Full hinting
\li Vertical hinting
\li Vertical hinting
\li Full hinting
\row
\li FreeType
\li Operating System setting
\li No hinting
\li Vertical hinting (light)
\li Full hinting
\row
\li Cocoa on \macos
\li No hinting
\li No hinting
\li No hinting
\li No hinting
\endtable
\note Please be aware that altering the hinting preference on Windows is available through
the DirectWrite font engine. This is available on Windows Vista after installing the platform
update, and on Windows 7. In order to use this extension, configure Qt using -directwrite.
The target application will then depend on the availability of DirectWrite on the target
system.
*/
/*!
\since 4.8
Set the preference for the hinting level of the glyphs to \a hintingPreference. This is a hint
to the underlying font rendering system to use a certain level of hinting, and has varying
support across platforms. See the table in the documentation for QFont::HintingPreference for
more details.
The default hinting preference is QFont::PreferDefaultHinting.
*/
void QFont::setHintingPreference(HintingPreference hintingPreference)
{
if ((resolve_mask & QFont::HintingPreferenceResolved) && d->request.hintingPreference == hintingPreference)
return;
detach();
d->request.hintingPreference = hintingPreference;
resolve_mask |= QFont::HintingPreferenceResolved;