ICU 63.1  63.1
ParagraphLayout.h
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1 // © 2016 and later: Unicode, Inc. and others.
2 // License & terms of use: http://www.unicode.org/copyright.html
3 /*
4  **********************************************************************
5  * Copyright (C) 2002-2014, International Business Machines
6  * Corporation and others. All Rights Reserved.
7  **********************************************************************
8  */
9 
10 #ifndef __PARAGRAPHLAYOUT_H
11 
12 #define __PARAGRAPHLAYOUT_H
13 
19 /*
20  * ParagraphLayout doesn't make much sense without
21  * BreakIterator...
22  */
23 #include "unicode/uscript.h"
24 #if ! UCONFIG_NO_BREAK_ITERATION
25 
26 #include "layout/LETypes.h"
27 #include "layout/LEFontInstance.h"
28 #include "layout/LayoutEngine.h"
29 #include "unicode/ubidi.h"
30 #include "unicode/brkiter.h"
31 
32 #include "layout/RunArrays.h"
33 
35 
52 {
53 public:
54  class VisualRun;
55 
67  class U_LAYOUTEX_API Line : public UObject
68  {
69  public:
78  ~Line();
79 
87  inline le_int32 countRuns() const;
88 
97  le_int32 getAscent() const;
98 
107  le_int32 getDescent() const;
108 
117  le_int32 getLeading() const;
118 
128  le_int32 getWidth() const;
129 
145  const VisualRun *getVisualRun(le_int32 runIndex) const;
146 
152  static inline UClassID getStaticClassID() { return (UClassID)&fgClassID; }
153 
159  virtual inline UClassID getDynamicClassID() const { return getStaticClassID(); }
160 
161  private:
162 
167  static const char fgClassID;
168 
169  friend class ParagraphLayout;
170 
171  le_int32 fAscent;
172  le_int32 fDescent;
173  le_int32 fLeading;
174 
175  le_int32 fRunCount;
176  le_int32 fRunCapacity;
177 
178  VisualRun **fRuns;
179 
180  inline Line();
181  inline Line(const Line &other);
182  inline Line &operator=(const Line & /*other*/) { return *this; };
183 
184  void computeMetrics();
185 
186  void append(const LEFontInstance *font, UBiDiDirection direction, le_int32 glyphCount,
187  const LEGlyphID glyphs[], const float positions[], const le_int32 glyphToCharMap[]);
188  };
189 
206  {
207  public:
220  inline const LEFontInstance *getFont() const;
221 
230  inline UBiDiDirection getDirection() const;
231 
239  inline le_int32 getGlyphCount() const;
240 
251  inline const LEGlyphID *getGlyphs() const;
252 
266  inline const float *getPositions() const;
267 
278  inline const le_int32 *getGlyphToCharMap() const;
279 
288  inline le_int32 getAscent() const;
289 
298  inline le_int32 getDescent() const;
299 
308  inline le_int32 getLeading() const;
309 
315  static inline UClassID getStaticClassID() { return (UClassID)&fgClassID; }
316 
322  virtual inline UClassID getDynamicClassID() const { return getStaticClassID(); }
323 
324  private:
325 
330  static const char fgClassID;
331 
332  const LEFontInstance *fFont;
333  const UBiDiDirection fDirection;
334 
335  const le_int32 fGlyphCount;
336 
337  const LEGlyphID *fGlyphs;
338  const float *fPositions;
339  const le_int32 *fGlyphToCharMap;
340 
341  friend class Line;
342 
343  inline VisualRun();
344  inline VisualRun(const VisualRun &other);
345  inline VisualRun &operator=(const VisualRun &/*other*/) { return *this; };
346 
347  inline VisualRun(const LEFontInstance *font, UBiDiDirection direction, le_int32 glyphCount,
348  const LEGlyphID glyphs[], const float positions[], const le_int32 glyphToCharMap[]);
349 
350  ~VisualRun();
351  };
352 
396  ParagraphLayout(const LEUnicode chars[], le_int32 count,
397  const FontRuns *fontRuns,
398  const ValueRuns *levelRuns,
399  const ValueRuns *scriptRuns,
400  const LocaleRuns *localeRuns,
401  UBiDiLevel paragraphLevel, le_bool vertical,
402  LEErrorCode &status);
403 
410  ~ParagraphLayout();
411 
412  // Note: the following is #if 0'd out because there's no good
413  // way to implement it without either calling layoutEngineFactory()
414  // or duplicating the logic there...
415 #if 0
416 
431  static le_bool isComplex(const LEUnicode chars[], le_int32 count, const FontRuns *fontRuns);
432 #else
433 
445  static le_bool isComplex(const LEUnicode chars[], le_int32 count);
446 
447 #endif
448 
458  inline UBiDiLevel getParagraphLevel();
459 
469  inline UBiDiDirection getTextDirection();
470 
479  virtual le_int32 getAscent() const;
480 
489  virtual le_int32 getDescent() const;
490 
499  virtual le_int32 getLeading() const;
500 
507  inline void reflow();
508 
509 #ifndef U_HIDE_INTERNAL_API
510 
519  inline le_bool isDone() const;
520 #endif /* U_HIDE_INTERNAL_API */
521 
539  Line *nextLine(float width);
540 
546  static inline UClassID getStaticClassID() { return (UClassID)&fgClassID; }
547 
553  virtual inline UClassID getDynamicClassID() const { return getStaticClassID(); }
554 
555 private:
556 
557 
562  static const char fgClassID;
563 
564  struct StyleRunInfo
565  {
566  LayoutEngine *engine;
567  const LEFontInstance *font;
568  const Locale *locale;
569  LEGlyphID *glyphs;
570  float *positions;
571  UScriptCode script;
572  UBiDiLevel level;
573  le_int32 runBase;
574  le_int32 runLimit;
575  le_int32 glyphBase;
576  le_int32 glyphCount;
577  };
578 
579  ParagraphLayout() {};
580  ParagraphLayout(const ParagraphLayout & /*other*/) : UObject( ){};
581  inline ParagraphLayout &operator=(const ParagraphLayout & /*other*/) { return *this; };
582 
583  void computeLevels(UBiDiLevel paragraphLevel);
584 
585  Line *computeVisualRuns();
586  void appendRun(Line *line, le_int32 run, le_int32 firstChar, le_int32 lastChar);
587 
588  void computeScripts();
589 
590  void computeLocales();
591 
592  void computeSubFonts(const FontRuns *fontRuns, LEErrorCode &status);
593 
594  void computeMetrics();
595 
596  le_int32 getLanguageCode(const Locale *locale);
597 
598  le_int32 getCharRun(le_int32 charIndex);
599 
600  static le_bool isComplex(UScriptCode script);
601 
602  le_int32 previousBreak(le_int32 charIndex);
603 
604 
605  const LEUnicode *fChars;
606  le_int32 fCharCount;
607 
608  const FontRuns *fFontRuns;
609  const ValueRuns *fLevelRuns;
610  const ValueRuns *fScriptRuns;
611  const LocaleRuns *fLocaleRuns;
612 
613  le_bool fVertical;
614  le_bool fClientLevels;
615  le_bool fClientScripts;
616  le_bool fClientLocales;
617 
618  UBiDiLevel *fEmbeddingLevels;
619 
620  le_int32 fAscent;
621  le_int32 fDescent;
622  le_int32 fLeading;
623 
624  le_int32 *fGlyphToCharMap;
625  le_int32 *fCharToMinGlyphMap;
626  le_int32 *fCharToMaxGlyphMap;
627  float *fGlyphWidths;
628  le_int32 fGlyphCount;
629 
630  UBiDi *fParaBidi;
631  UBiDi *fLineBidi;
632 
633  le_int32 *fStyleRunLimits;
634  le_int32 *fStyleIndices;
635  StyleRunInfo *fStyleRunInfo;
636  le_int32 fStyleRunCount;
637 
638  BreakIterator *fBreakIterator;
639  le_int32 fLineStart;
640  le_int32 fLineEnd;
641 
642  le_int32 fFirstVisualRun;
643  le_int32 fLastVisualRun;
644  float fVisualRunLastX;
645  float fVisualRunLastY;
646 };
647 
648 inline UBiDiLevel ParagraphLayout::getParagraphLevel()
649 {
650  return ubidi_getParaLevel(fParaBidi);
651 }
652 
653 inline UBiDiDirection ParagraphLayout::getTextDirection()
654 {
655  return ubidi_getDirection(fParaBidi);
656 }
657 
658 inline void ParagraphLayout::reflow()
659 {
660  fLineEnd = 0;
661 }
662 
663 inline ParagraphLayout::Line::Line()
664  : UObject(), fAscent(0), fDescent(0), fLeading(0), fRunCount(0), fRunCapacity(0), fRuns(NULL)
665 {
666  // nothing else to do
667 }
668 
669 inline ParagraphLayout::Line::Line(const Line & /*other*/)
670  : UObject(), fAscent(0), fDescent(0), fLeading(0), fRunCount(0), fRunCapacity(0), fRuns(NULL)
671 {
672  // nothing else to do
673 }
674 
675 inline le_int32 ParagraphLayout::Line::countRuns() const
676 {
677  return fRunCount;
678 }
679 
680 inline const LEFontInstance *ParagraphLayout::VisualRun::getFont() const
681 {
682  return fFont;
683 }
684 
685 inline UBiDiDirection ParagraphLayout::VisualRun::getDirection() const
686 {
687  return fDirection;
688 }
689 
690 inline le_int32 ParagraphLayout::VisualRun::getGlyphCount() const
691 {
692  return fGlyphCount;
693 }
694 
695 inline const LEGlyphID *ParagraphLayout::VisualRun::getGlyphs() const
696 {
697  return fGlyphs;
698 }
699 
700 inline const float *ParagraphLayout::VisualRun::getPositions() const
701 {
702  return fPositions;
703 }
704 
705 inline const le_int32 *ParagraphLayout::VisualRun::getGlyphToCharMap() const
706 {
707  return fGlyphToCharMap;
708 }
709 
710 inline le_int32 ParagraphLayout::VisualRun::getAscent() const
711 {
712  return fFont->getAscent();
713 }
714 
715 inline le_int32 ParagraphLayout::VisualRun::getDescent() const
716 {
717  return fFont->getDescent();
718 }
719 
720 inline le_int32 ParagraphLayout::VisualRun::getLeading() const
721 {
722  return fFont->getLeading();
723 }
724 
725 inline ParagraphLayout::VisualRun::VisualRun()
726  : UObject(), fFont(NULL), fDirection(UBIDI_LTR), fGlyphCount(0), fGlyphs(NULL), fPositions(NULL), fGlyphToCharMap(NULL)
727 {
728  // nothing
729 }
730 
731 inline ParagraphLayout::VisualRun::VisualRun(const VisualRun &/*other*/)
732  : UObject(), fFont(NULL), fDirection(UBIDI_LTR), fGlyphCount(0), fGlyphs(NULL), fPositions(NULL), fGlyphToCharMap(NULL)
733 {
734  // nothing
735 }
736 
737 inline ParagraphLayout::VisualRun::VisualRun(const LEFontInstance *font, UBiDiDirection direction, le_int32 glyphCount,
738  const LEGlyphID glyphs[], const float positions[], const le_int32 glyphToCharMap[])
739  : fFont(font), fDirection(direction), fGlyphCount(glyphCount),
740  fGlyphs(glyphs), fPositions(positions), fGlyphToCharMap(glyphToCharMap)
741 {
742  // nothing else needs to be done!
743 }
744 
746 #endif
747 #endif
C++ API: Break Iterator.
virtual UClassID getDynamicClassID() const
ICU "poor man's RTTI", returns a UClassID for the actual class.
static UClassID getStaticClassID()
ICU "poor man's RTTI", returns a UClassID for this class.
C API: Bidi algorithm.
virtual UClassID getDynamicClassID() const
ICU "poor man's RTTI", returns a UClassID for the actual class.
virtual UClassID getDynamicClassID() const
ICU "poor man's RTTI", returns a UClassID for the actual class.
void * UClassID
UClassID is used to identify classes without using the compiler's RTTI.
Definition: uobject.h:90
UScriptCode
Constants for ISO 15924 script codes.
Definition: uscript.h:54
uint8_t UBiDiLevel
UBiDiLevel is the type of the level values in this Bidi implementation.
Definition: ubidi.h:336
static UClassID getStaticClassID()
ICU "poor man's RTTI", returns a UClassID for this class.
The FontRuns class associates pointers to LEFontInstance objects with runs of text.
Definition: RunArrays.h:272
The LocaleRuns class associates pointers to Locale objects with runs of text.
Definition: RunArrays.h:409
This object represents a single visual run in a line of text in a paragraph.
C API: Unicode Script Information.
UBiDiDirection
UBiDiDirection values indicate the text direction.
Definition: ubidi.h:425
This class represents a single line of text in a ParagraphLayout.
UBiDiDirection ubidi_getDirection(const UBiDi *pBiDi)
Get the directionality of the text.
#define U_NAMESPACE_BEGIN
This is used to begin a declaration of a public ICU C++ API.
Definition: uversion.h:137
The BreakIterator class implements methods for finding the location of boundaries in text...
Definition: brkiter.h:102
#define NULL
Define NULL if necessary, to nullptr for C++ and to ((void *)0) for C.
Definition: utypes.h:188
UBiDiLevel ubidi_getParaLevel(const UBiDi *pBiDi)
Get the paragraph level of the text.
ParagraphLayout.
Left-to-right text.
Definition: ubidi.h:437
#define U_NAMESPACE_END
This is used to end a declaration of a public ICU C++ API.
Definition: uversion.h:138
struct UBiDi UBiDi
Definition: ubidi.h:482
#define U_LAYOUTEX_API
Set to export library symbols from inside the layout extensions library, and to import them from outs...
Definition: utypes.h:303
C++ API: base class for building classes which represent data that is associated with runs of text...
The ValueRuns class associates integer values with runs of text.
Definition: RunArrays.h:548
static UClassID getStaticClassID()
ICU "poor man's RTTI", returns a UClassID for this class.
UObject is the common ICU "boilerplate" class.
Definition: uobject.h:220
A Locale object represents a specific geographical, political, or cultural region.
Definition: locid.h:192