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SkBidiFactory Class Referenceabstract

#include <SkUnicode_icu_bidi.h>

Inheritance diagram for SkBidiFactory:
SkRefCnt SkRefCntBase SkBidiICUFactory SkBidiSubsetFactory

Public Types

using BidiCloseCallback = void(*)(UBiDi *bidi)
 

Public Member Functions

std::unique_ptr< SkBidiIterator > MakeIterator (const uint16_t utf16[], int utf16Units, SkBidiIterator::Direction dir) const
 
std::unique_ptr< SkBidiIterator > MakeIterator (const char utf8[], int utf8Units, SkBidiIterator::Direction dir) const
 
bool ExtractBidi (const char utf8[], int utf8Units, SkUnicode::TextDirection dir, std::vector< SkUnicode::BidiRegion > *bidiRegions) const
 
virtual const char * errorName (UErrorCode status) const =0
 
virtual BidiCloseCallback bidi_close_callback () const =0
 
virtual UBiDiDirection bidi_getDirection (const UBiDi *bidi) const =0
 
virtual SkBidiIterator::Position bidi_getLength (const UBiDi *bidi) const =0
 
virtual SkBidiIterator::Level bidi_getLevelAt (const UBiDi *bidi, int pos) const =0
 
virtual UBiDi * bidi_openSized (int32_t maxLength, int32_t maxRunCount, UErrorCode *pErrorCode) const =0
 
virtual void bidi_setPara (UBiDi *bidi, const UChar *text, int32_t length, UBiDiLevel paraLevel, UBiDiLevel *embeddingLevels, UErrorCode *status) const =0
 
virtual void bidi_reorderVisual (const SkUnicode::BidiLevel runLevels[], int levelsCount, int32_t logicalFromVisual[]) const =0
 
- Public Member Functions inherited from SkRefCntBase
 SkRefCntBase ()
 
virtual ~SkRefCntBase ()
 
bool unique () const
 
void ref () const
 
void unref () const
 

Detailed Description

Definition at line 22 of file SkUnicode_icu_bidi.h.

Member Typedef Documentation

◆ BidiCloseCallback

using SkBidiFactory::BidiCloseCallback = void(*)(UBiDi* bidi)

Definition at line 37 of file SkUnicode_icu_bidi.h.

Member Function Documentation

◆ bidi_close_callback()

virtual BidiCloseCallback SkBidiFactory::bidi_close_callback ( ) const
pure virtual

Implemented in SkBidiICUFactory, and SkBidiSubsetFactory.

◆ bidi_getDirection()

virtual UBiDiDirection SkBidiFactory::bidi_getDirection ( const UBiDi *  bidi) const
pure virtual

Implemented in SkBidiICUFactory, and SkBidiSubsetFactory.

◆ bidi_getLength()

virtual SkBidiIterator::Position SkBidiFactory::bidi_getLength ( const UBiDi *  bidi) const
pure virtual

Implemented in SkBidiICUFactory, and SkBidiSubsetFactory.

◆ bidi_getLevelAt()

virtual SkBidiIterator::Level SkBidiFactory::bidi_getLevelAt ( const UBiDi *  bidi,
int  pos 
) const
pure virtual

Implemented in SkBidiICUFactory, and SkBidiSubsetFactory.

◆ bidi_openSized()

virtual UBiDi * SkBidiFactory::bidi_openSized ( int32_t  maxLength,
int32_t  maxRunCount,
UErrorCode *  pErrorCode 
) const
pure virtual

Implemented in SkBidiICUFactory, and SkBidiSubsetFactory.

◆ bidi_reorderVisual()

virtual void SkBidiFactory::bidi_reorderVisual ( const SkUnicode::BidiLevel  runLevels[],
int  levelsCount,
int32_t  logicalFromVisual[] 
) const
pure virtual

Implemented in SkBidiICUFactory, and SkBidiSubsetFactory.

◆ bidi_setPara()

virtual void SkBidiFactory::bidi_setPara ( UBiDi *  bidi,
const UChar *  text,
int32_t  length,
UBiDiLevel  paraLevel,
UBiDiLevel *  embeddingLevels,
UErrorCode *  status 
) const
pure virtual

Implemented in SkBidiICUFactory, and SkBidiSubsetFactory.

◆ errorName()

virtual const char * SkBidiFactory::errorName ( UErrorCode  status) const
pure virtual

Implemented in SkBidiICUFactory, and SkBidiSubsetFactory.

◆ ExtractBidi()

bool SkBidiFactory::ExtractBidi ( const char  utf8[],
int  utf8Units,
SkUnicode::TextDirection  dir,
std::vector< SkUnicode::BidiRegion > *  bidiRegions 
) const

Definition at line 88 of file SkUnicode_icu_bidi.cpp.

91 {
92 // Convert to UTF16 since for now bidi iterator only operates on utf16
93 auto utf16 = SkUnicode::convertUtf8ToUtf16(utf8, utf8Units);
94
95 // Create bidi iterator
96 UErrorCode status = U_ZERO_ERROR;
97 SkUnicodeBidi bidi(this->bidi_openSized(utf16.size(), 0, &status), this->bidi_close_callback());
98 if (U_FAILURE(status)) {
99 SkDEBUGF("Bidi error: %s", this->errorName(status));
100 return false;
101 }
102 SkASSERT(bidi);
103 uint8_t bidiLevel = (dir == SkUnicode::TextDirection::kLTR) ? UBIDI_LTR : UBIDI_RTL;
104 // The required lifetime of utf16 isn't well documented.
105 // It appears it isn't used after ubidi_setPara except through ubidi_getText.
106 this->bidi_setPara(
107 bidi.get(), (const UChar*)utf16.c_str(), utf16.size(), bidiLevel, nullptr, &status);
108 if (U_FAILURE(status)) {
109 SkDEBUGF("Bidi error: %s", this->errorName(status));
110 return false;
111 }
112
113 // Iterate through bidi regions and the result positions into utf8
114 const char* start8 = utf8;
115 const char* end8 = utf8 + utf8Units;
116 SkUnicode::BidiLevel currentLevel = 0;
117
118 SkUnicode::Position pos8 = 0;
119 SkUnicode::Position pos16 = 0;
120 SkUnicode::Position end16 = this->bidi_getLength(bidi.get());
121
122 if (end16 == 0) {
123 return true;
124 }
125 if (this->bidi_getDirection(bidi.get()) != UBIDI_MIXED) {
126 // The entire paragraph is unidirectional.
127 bidiRegions->emplace_back(0, utf8Units, this->bidi_getLevelAt(bidi.get(), 0));
128 return true;
129 }
130
131 while (pos16 < end16) {
132 auto level = this->bidi_getLevelAt(bidi.get(), pos16);
133 if (pos16 == 0) {
134 currentLevel = level;
135 } else if (level != currentLevel) {
136 SkUnicode::Position end = start8 - utf8;
137 bidiRegions->emplace_back(pos8, end, currentLevel);
138 currentLevel = level;
139 pos8 = end;
140 }
141 SkUnichar u = utf8_next(&start8, end8);
142 pos16 += SkUTF::ToUTF16(u);
143 }
144 SkUnicode::Position end = start8 - utf8;
145 if (end != pos8) {
146 bidiRegions->emplace_back(pos8, end, currentLevel);
147 }
148 return true;
149}
SkASSERT
#define SkASSERT(cond)
Definition SkAssert.h:116
SkDEBUGF
#define SkDEBUGF(...)
Definition SkDebug.h:24
utf8_next
static SkUnichar utf8_next(const char **ptr, const char *end)
Definition SkShaper.cpp:84
SkUnicodeBidi
std::unique_ptr< SkBidiIterator > SkUnicodeBidi
Definition SkShaper_skunicode.cpp:21
SkUnichar
int32_t SkUnichar
Definition SkTypes.h:175
SkBidiFactory::bidi_setPara
virtual void bidi_setPara(UBiDi *bidi, const UChar *text, int32_t length, UBiDiLevel paraLevel, UBiDiLevel *embeddingLevels, UErrorCode *status) const =0
SkBidiFactory::bidi_getLevelAt
virtual SkBidiIterator::Level bidi_getLevelAt(const UBiDi *bidi, int pos) const =0
SkBidiFactory::bidi_getLength
virtual SkBidiIterator::Position bidi_getLength(const UBiDi *bidi) const =0
SkBidiFactory::bidi_openSized
virtual UBiDi * bidi_openSized(int32_t maxLength, int32_t maxRunCount, UErrorCode *pErrorCode) const =0
SkBidiFactory::bidi_getDirection
virtual UBiDiDirection bidi_getDirection(const UBiDi *bidi) const =0
SkBidiFactory::errorName
virtual const char * errorName(UErrorCode status) const =0
SkUnicode::convertUtf8ToUtf16
static std::u16string convertUtf8ToUtf16(const char *utf8, int utf8Units)
Definition SkUnicode.cpp:32
SkUnicode::Position
size_t Position
Definition SkUnicode.h:98
SkUnicode::BidiLevel
uint8_t BidiLevel
Definition SkUnicode.h:99
end
glong glong end
Definition fl_accessible_text_field.cc:40
SkUTF::ToUTF16
SK_SPI size_t ToUTF16(SkUnichar uni, uint16_t utf16[2]=nullptr)
Definition SkUTF.cpp:243
flutter::dir
DEF_SWITCHES_START aot vmservice shared library Name of the *so containing AOT compiled Dart assets for launching the service isolate vm snapshot The VM snapshot data that will be memory mapped as read only SnapshotAssetPath must be present isolate snapshot The isolate snapshot data that will be memory mapped as read only SnapshotAssetPath must be present cache dir Path to the cache directory This is different from the persistent_cache_path in embedder which is used for Skia shader cache icu native lib Path to the library file that exports the ICU data vm service The hostname IP address on which the Dart VM Service should be served If not defaults to or::depending on whether ipv6 is specified vm service A custom Dart VM Service port The default is to pick a randomly available open port disable vm Disable the Dart VM Service The Dart VM Service is never available in release mode disable vm service Disable mDNS Dart VM Service publication Bind to the IPv6 localhost address for the Dart VM Service Ignored if vm service host is set endless trace Enable an endless trace buffer The default is a ring buffer This is useful when very old events need to viewed For during application launch Memory usage will continue to grow indefinitely however Start app with an specific route defined on the framework flutter assets dir
Definition switches.h:145
generate_pom_file.utf8
utf8(s)
Definition generate_pom_file.py:67
run_tests.level
level
Definition run_tests.py:142

◆ MakeIterator() [1/2]

std::unique_ptr< SkBidiIterator > SkBidiFactory::MakeIterator ( const char  utf8[],
int  utf8Units,
SkBidiIterator::Direction  dir 
) const

Definition at line 60 of file SkUnicode_icu_bidi.cpp.

62 {
63 // Convert utf8 into utf16 since ubidi only accepts utf16
64 if (!SkTFitsIn<int32_t>(utf8Units)) {
65 SkDEBUGF("Bidi error: text too long");
66 return nullptr;
67 }
68
69 // Getting the length like this seems to always set U_BUFFER_OVERFLOW_ERROR
70 int utf16Units = SkUTF::UTF8ToUTF16(nullptr, 0, utf8, utf8Units);
71 if (utf16Units < 0) {
72 SkDEBUGF("Bidi error: Invalid utf8 input");
73 return nullptr;
74 }
75 std::unique_ptr<uint16_t[]> utf16(new uint16_t[utf16Units]);
76 SkDEBUGCODE(int dstLen =) SkUTF::UTF8ToUTF16(utf16.get(), utf16Units, utf8, utf8Units);
77 SkASSERT(dstLen == utf16Units);
78
79 return MakeIterator(utf16.get(), utf16Units, dir);
80}
SkDEBUGCODE
#define SkDEBUGCODE(...)
Definition SkDebug.h:23
SkBidiFactory::MakeIterator
std::unique_ptr< SkBidiIterator > MakeIterator(const uint16_t utf16[], int utf16Units, SkBidiIterator::Direction dir) const
Definition SkUnicode_icu_bidi.cpp:38
SkUTF
Definition SkUTF.h:13
SkUTF::UTF8ToUTF16
SK_SPI int UTF8ToUTF16(uint16_t dst[], int dstCapacity, const char src[], size_t srcByteLength)
Definition SkUTF.cpp:259

◆ MakeIterator() [2/2]

std::unique_ptr< SkBidiIterator > SkBidiFactory::MakeIterator ( const uint16_t  utf16[],
int  utf16Units,
SkBidiIterator::Direction  dir 
) const

Definition at line 38 of file SkUnicode_icu_bidi.cpp.

40 {
41 UErrorCode status = U_ZERO_ERROR;
42 SkUnicodeBidi bidi(this->bidi_openSized(utf16Units, 0, &status), this->bidi_close_callback());
43 if (U_FAILURE(status)) {
44 SkDEBUGF("Bidi error: %s", this->errorName(status));
45 return nullptr;
46 }
47 SkASSERT(bidi);
48 uint8_t bidiLevel = (dir == SkBidiIterator::kLTR) ? UBIDI_LTR : UBIDI_RTL;
49 // The required lifetime of utf16 isn't well documented.
50 // It appears it isn't used after ubidi_setPara except through ubidi_getText.
51 this->bidi_setPara(bidi.get(), (const UChar*)utf16, utf16Units, bidiLevel, nullptr, &status);
52 if (U_FAILURE(status)) {
53 SkDEBUGF("Bidi error: %s", this->errorName(status));
54 return nullptr;
55 }
56 return std::unique_ptr<SkBidiIterator>(
57 new SkBidiIterator_icu(std::move(bidi), sk_ref_sp(this)));
58}
sk_ref_sp
sk_sp< T > sk_ref_sp(T *obj)
Definition SkRefCnt.h:381
SkBidiFactory::bidi_close_callback
virtual BidiCloseCallback bidi_close_callback() const =0
The documentation for this class was generated from the following files:
Generated on Fri Apr 26 2024 06:19:43 for Flutter Engine by doxygen 1.9.8