ParagraphLayout.h

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// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
 **********************************************************************
 *   Copyright (C) 2002-2014, International Business Machines
 *   Corporation and others.  All Rights Reserved.
 **********************************************************************
 */
 
#ifndef __PARAGRAPHLAYOUT_H
 
#define __PARAGRAPHLAYOUT_H
 
/*
 * ParagraphLayout doesn't make much sense without
 * BreakIterator...
 */
#include "unicode/uscript.h"
#if ! UCONFIG_NO_BREAK_ITERATION
 
#include "layout/LETypes.h"
#include "layout/LEFontInstance.h"
#include "layout/LayoutEngine.h"
#include "unicode/ubidi.h"
#include "unicode/brkiter.h"
 
#include "layout/RunArrays.h"
 
U_NAMESPACE_BEGIN
 
class U_LAYOUTEX_API ParagraphLayout : public UObject
{
public:
    class VisualRun;
 
    class U_LAYOUTEX_API Line : public UObject
    {
    public:
        ~Line();
 
        inline le_int32 countRuns() const;
 
        le_int32 getAscent() const;
 
        le_int32 getDescent() const;
 
        le_int32 getLeading() const;
 
        le_int32 getWidth() const;
    
        const VisualRun *getVisualRun(le_int32 runIndex) const;
 
        static inline UClassID getStaticClassID() { return (UClassID)&fgClassID; }
 
        inline UClassID getDynamicClassID() const override { return getStaticClassID(); }
 
    private:
 
        static const char fgClassID;
 
        friend class ParagraphLayout;
 
        le_int32 fAscent;
        le_int32 fDescent;
        le_int32 fLeading;
 
        le_int32 fRunCount;
        le_int32 fRunCapacity;
 
        VisualRun **fRuns;
 
        inline Line();
        inline Line(const Line &other);
        inline Line &operator=(const Line & /*other*/) { return *this; }
 
        void computeMetrics();
 
        void append(const LEFontInstance *font, UBiDiDirection direction, le_int32 glyphCount,
                    const LEGlyphID glyphs[], const float positions[], const le_int32 glyphToCharMap[]);
    };
 
    class U_LAYOUTEX_API VisualRun : public UObject
    {
    public:
        inline const LEFontInstance *getFont() const;
 
        inline UBiDiDirection getDirection() const;
 
        inline le_int32 getGlyphCount() const;
 
        inline const LEGlyphID *getGlyphs() const;
 
        inline const float *getPositions() const;
 
        inline const le_int32 *getGlyphToCharMap() const;
 
        inline le_int32 getAscent() const;
 
        inline le_int32 getDescent() const;
 
        inline le_int32 getLeading() const;
 
        static inline UClassID getStaticClassID() { return (UClassID)&fgClassID; }
 
        inline UClassID getDynamicClassID() const override { return getStaticClassID(); }
 
    private:
 
        static const char fgClassID;
 
        const LEFontInstance *fFont;
        const UBiDiDirection  fDirection;
 
        const le_int32 fGlyphCount;
 
        const LEGlyphID *fGlyphs;
        const float     *fPositions;
        const le_int32  *fGlyphToCharMap;
 
        friend class Line;
 
        inline VisualRun();
        inline VisualRun(const VisualRun &other);
        inline VisualRun &operator=(const VisualRun &/*other*/) { return *this; }
 
        inline VisualRun(const LEFontInstance *font, UBiDiDirection direction, le_int32 glyphCount,
                  const LEGlyphID glyphs[], const float positions[], const le_int32 glyphToCharMap[]);
 
        ~VisualRun();
    };
 
    ParagraphLayout(const LEUnicode chars[], le_int32 count,
                    const FontRuns *fontRuns,
                    const ValueRuns *levelRuns,
                    const ValueRuns *scriptRuns,
                    const LocaleRuns *localeRuns,
                    UBiDiLevel paragraphLevel, le_bool vertical,
                    LEErrorCode &status);
 
    ~ParagraphLayout();
 
    // Note: the following is #if 0'd out because there's no good
    // way to implement it without either calling layoutEngineFactory()
    // or duplicating the logic there...
#if 0
    static le_bool isComplex(const LEUnicode chars[], le_int32 count, const FontRuns *fontRuns);
#else
    static le_bool isComplex(const LEUnicode chars[], le_int32 count);
 
#endif
 
    inline UBiDiLevel getParagraphLevel();
 
    inline UBiDiDirection getTextDirection();
 
    virtual le_int32 getAscent() const;
 
    virtual le_int32 getDescent() const;
 
    virtual le_int32 getLeading() const;
 
    inline void reflow();
 
#ifndef U_HIDE_INTERNAL_API
    inline le_bool isDone() const;
#endif  /* U_HIDE_INTERNAL_API */
 
    Line *nextLine(float width);
 
    static inline UClassID getStaticClassID() { return (UClassID)&fgClassID; }
 
    inline UClassID getDynamicClassID() const override { return getStaticClassID(); }
 
private:
 
 
    static const char fgClassID;
 
    struct StyleRunInfo
    {
          LayoutEngine   *engine;
    const LEFontInstance *font;
    const Locale         *locale;
          LEGlyphID      *glyphs;
          float          *positions;
          UScriptCode     script;
          UBiDiLevel      level;
          le_int32        runBase;
          le_int32        runLimit;
          le_int32        glyphBase;
          le_int32        glyphCount;
    };
 
    ParagraphLayout() {}
    ParagraphLayout(const ParagraphLayout & /*other*/) : UObject( ){}
    inline ParagraphLayout &operator=(const ParagraphLayout & /*other*/) { return *this; }
 
    void computeLevels(UBiDiLevel paragraphLevel);
 
    Line *computeVisualRuns();
    void appendRun(Line *line, le_int32 run, le_int32 firstChar, le_int32 lastChar);
 
    void computeScripts();
 
    void computeLocales();
 
    void computeSubFonts(const FontRuns *fontRuns, LEErrorCode &status);
 
    void computeMetrics();
 
    le_int32 getLanguageCode(const Locale *locale);
 
    le_int32 getCharRun(le_int32 charIndex);
 
    static le_bool isComplex(UScriptCode script);
 
    le_int32 previousBreak(le_int32 charIndex);
 
 
    const LEUnicode *fChars;
          le_int32   fCharCount;
 
    const FontRuns   *fFontRuns;
    const ValueRuns  *fLevelRuns;
    const ValueRuns  *fScriptRuns;
    const LocaleRuns *fLocaleRuns;
 
          le_bool fVertical;
          le_bool fClientLevels;
          le_bool fClientScripts;
          le_bool fClientLocales;
 
          UBiDiLevel *fEmbeddingLevels;
 
          le_int32 fAscent;
          le_int32 fDescent;
          le_int32 fLeading;
 
          le_int32 *fGlyphToCharMap;
          le_int32 *fCharToMinGlyphMap;
          le_int32 *fCharToMaxGlyphMap;
          float    *fGlyphWidths;
          le_int32  fGlyphCount;
 
          UBiDi *fParaBidi;
          UBiDi *fLineBidi;
 
          le_int32     *fStyleRunLimits;
          le_int32     *fStyleIndices;
          StyleRunInfo *fStyleRunInfo;
          le_int32      fStyleRunCount;
 
          BreakIterator *fBreakIterator;
          le_int32       fLineStart;
          le_int32       fLineEnd;
 
          le_int32       fFirstVisualRun;
          le_int32       fLastVisualRun;
          float          fVisualRunLastX;
          float          fVisualRunLastY;
};
 
inline UBiDiLevel ParagraphLayout::getParagraphLevel()
{
    return ubidi_getParaLevel(fParaBidi);
}
 
inline UBiDiDirection ParagraphLayout::getTextDirection()
{
    return ubidi_getDirection(fParaBidi);
}
 
inline void ParagraphLayout::reflow()
{
    fLineEnd = 0;
}
 
inline ParagraphLayout::Line::Line()
    : UObject(), fAscent(0), fDescent(0), fLeading(0), fRunCount(0), fRunCapacity(0), fRuns(nullptr)
{
    // nothing else to do
}
 
inline ParagraphLayout::Line::Line(const Line & /*other*/)
    : UObject(), fAscent(0), fDescent(0), fLeading(0), fRunCount(0), fRunCapacity(0), fRuns(nullptr)
{
    // nothing else to do
}
 
inline le_int32 ParagraphLayout::Line::countRuns() const
{
    return fRunCount;
}
 
inline const LEFontInstance *ParagraphLayout::VisualRun::getFont() const
{
    return fFont;
}
 
inline UBiDiDirection ParagraphLayout::VisualRun::getDirection() const
{
    return fDirection;
}
 
inline le_int32