ICU 57.1  57.1
LayoutEngine.h
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1 /*
2  * (C) Copyright IBM Corp. and others 1998-2014 - All Rights Reserved
3  */
4 
5 #ifndef __LAYOUTENGINE_H
6 #define __LAYOUTENGINE_H
7 
8 #include "LETypes.h"
9 
16 
17 class LEFontInstance;
18 class LEGlyphFilter;
19 class LEGlyphStorage;
20 
72 public:
73 #ifndef U_HIDE_INTERNAL_API
74 
75  static const le_int32 kTypoFlagKern;
77  static const le_int32 kTypoFlagLiga;
78 #endif /* U_HIDE_INTERNAL_API */
79 
80 protected:
87 
96 
105 
114 
121 
129 
130 #ifndef U_HIDE_INTERNAL_API
131 
147  LayoutEngine(const LEFontInstance *fontInstance,
148  le_int32 scriptCode,
149  le_int32 languageCode,
150  le_int32 typoFlags,
151  LEErrorCode &success);
152 #endif /* U_HIDE_INTERNAL_API */
153 
154  // Do not enclose the protected default constructor with #ifndef U_HIDE_INTERNAL_API
155  // or else the compiler will create a public default constructor.
163  LayoutEngine();
164 
187  virtual le_int32 characterProcessing(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool rightToLeft,
188  LEUnicode *&outChars, LEGlyphStorage &glyphStorage, LEErrorCode &success);
189 
216  virtual le_int32 computeGlyphs(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool rightToLeft, LEGlyphStorage &glyphStorage, LEErrorCode &success);
217 
231  virtual void positionGlyphs(LEGlyphStorage &glyphStorage, float x, float y, LEErrorCode &success);
232 
253  virtual void adjustGlyphPositions(const LEUnicode chars[], le_int32 offset, le_int32 count, le_bool reverse, LEGlyphStorage &glyphStorage, LEErrorCode &success);
254 
268  virtual const void *getFontTable(LETag tableTag, size_t &length) const;
269 
273  virtual const void *getFontTable(LETag tableTag) const { size_t ignored; return getFontTable(tableTag, ignored); }
274 
300  virtual void mapCharsToGlyphs(const LEUnicode chars[], le_int32 offset, le_int32 count, le_bool reverse, le_bool mirror, LEGlyphStorage &glyphStorage, LEErrorCode &success);
301 
302 #ifndef U_HIDE_INTERNAL_API
303 
315  static void adjustMarkGlyphs(LEGlyphStorage &glyphStorage, LEGlyphFilter *markFilter, LEErrorCode &success);
316 
317 
336  static void adjustMarkGlyphs(const LEUnicode chars[], le_int32 charCount, le_bool reverse, LEGlyphStorage &glyphStorage, LEGlyphFilter *markFilter, LEErrorCode &success);
337 #endif /* U_HIDE_INTERNAL_API */
338 
339 public:
348  virtual ~LayoutEngine();
349 
375  virtual le_int32 layoutChars(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool rightToLeft, float x, float y, LEErrorCode &success);
376 
386  le_int32 getGlyphCount() const;
387 
398  void getGlyphs(LEGlyphID glyphs[], LEErrorCode &success) const;
399 
412  virtual void getGlyphs(le_uint32 glyphs[], le_uint32 extraBits, LEErrorCode &success) const;
413 
424  void getCharIndices(le_int32 charIndices[], LEErrorCode &success) const;
425 
437  void getCharIndices(le_int32 charIndices[], le_int32 indexBase, LEErrorCode &success) const;
438 
450  void getGlyphPositions(float positions[], LEErrorCode &success) const;
451 
466  void getGlyphPosition(le_int32 glyphIndex, float &x, float &y, LEErrorCode &success) const;
467 
475  virtual void reset();
476 
493  static LayoutEngine *layoutEngineFactory(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, LEErrorCode &success);
494 
499  static LayoutEngine *layoutEngineFactory(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, le_int32 typo_flags, LEErrorCode &success);
500 
506  virtual UClassID getDynamicClassID() const;
507 
513  static UClassID getStaticClassID();
514 
515 };
516 
518 #endif
uint32_t le_uint32
A type used for unsigned, 32-bit integers.
Definition: LETypes.h:41
le_uint32 LETag
Used for four character tags.
Definition: LETypes.h:93
#define U_LAYOUT_API
Set to export library symbols from inside the layout engine library, and to import them from outside...
Definition: utypes.h:359
void * UClassID
UClassID is used to identify classes without using the compiler's RTTI.
Definition: uobject.h:91
const LEFontInstance * fFontInstance
The font instance for the text font.
Definition: LayoutEngine.h:95
C API: Basic definitions for the ICU LayoutEngine.
int32_t le_int32
A type used for signed, 32-bit integers.
Definition: LETypes.h:34
UBool le_bool
A type used for boolean values.
Definition: LETypes.h:77
#define U_NAMESPACE_BEGIN
This is used to begin a declaration of a public ICU C++ API.
Definition: uversion.h:129
static const le_int32 kTypoFlagLiga
Definition: LayoutEngine.h:77
le_int32 fScriptCode
The script code for the text.
Definition: LayoutEngine.h:104
virtual const void * getFontTable(LETag tableTag) const
Definition: LayoutEngine.h:273
virtual UClassID getDynamicClassID() const
ICU4C "poor man's RTTI", returns a UClassID for the actual ICU class.
NOTE: This class is deprecated, please instead use HarfBuzz.
Definition: LayoutEngine.h:71
LEErrorCode
Error codes returned by the LayoutEngine.
Definition: LETypes.h:687
le_bool fFilterZeroWidth
TRUE if mapCharsToGlyphs should replace ZWJ / ZWNJ with a glyph with no contours. ...
Definition: LayoutEngine.h:128
#define U_NAMESPACE_END
This is used to end a declaration of a public ICU C++ API.
Definition: uversion.h:130
LEGlyphStorage * fGlyphStorage
The object which holds the glyph storage.
Definition: LayoutEngine.h:86
le_int32 fLanguageCode
The langauge code for the text.
Definition: LayoutEngine.h:113
UChar LEUnicode
Used to represent 16-bit Unicode code points.
Definition: LETypes.h:238
This is a virtual base class that serves as the interface between a LayoutEngine and the platform fon...
This class encapsulates the per-glyph storage used by the ICU LayoutEngine.
le_uint32 LEGlyphID
Used for glyph indices.
Definition: LETypes.h:112
static const le_int32 kTypoFlagKern
Definition: LayoutEngine.h:75
le_int32 fTypoFlags
The typographic control flags.
Definition: LayoutEngine.h:120
UObject is the common ICU "boilerplate" class.
Definition: uobject.h:221