vcl/inc/graphite_layout.hxx

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  19
  20 #ifndef INCLUDED_VCL_INC_GRAPHITE_LAYOUT_HXX
  21 #define INCLUDED_VCL_INC_GRAPHITE_LAYOUT_HXX
  22 // Description: An implementation of the SalLayout interface that uses the
  23 //              Graphite engine.
  24
  25 // We need this to enable namespace support in libgrengine headers.
  26 #define GR_NAMESPACE
  27
  28 // Standard Library
  29 #include <memory>
  30 #include <vector>
  31 #include <map>
  32 #include <utility>
  33 // Libraries
  34 #include <graphite2/Font.h>
  35 #include <graphite2/Segment.h>
  36 // Platform
  37 #include <sallayout.hxx>
  38 #include <vcl/dllapi.h>
  39 // Module
  40
  41 // Module type definitions and forward declarations.
  42 // SAL/VCL types
  43 class ServerFont;
  44
  45 // Graphite types
  46 namespace grutils { class GrFeatureParser; }
  47
  48 class GraphiteFaceWrapper
  49 {
  50 public:
  51     typedef std::map<int, gr_font*> GrFontMap;
  52     GraphiteFaceWrapper(gr_face * pFace) : m_pFace(pFace) {}
  53     ~GraphiteFaceWrapper()
  54     {
  55         GrFontMap::iterator i = m_fonts.begin();
  56         while (i != m_fonts.end())
  57             gr_font_destroy((*i++).second);
  58         m_fonts.clear();
  59         gr_face_destroy(m_pFace);
  60     }
  61     const gr_face * face() const { return m_pFace; }
  62     gr_font * font(int ppm) const
  63     {
  64         GrFontMap::const_iterator i = m_fonts.find(ppm);
  65         if (i != m_fonts.end())
  66             return i->second;
  67         return NULL;
  68     };
  69     void addFont(int ppm, gr_font * pFont)
  70     {
  71         if (m_fonts[ppm])
  72             gr_font_destroy(m_fonts[ppm]);
  73         m_fonts[ppm] = pFont;
  74     }
  75 private:
  76     gr_face * m_pFace;
  77     GrFontMap m_fonts;
  78 };
  79
  80 // This class uses the SIL Graphite engine to provide complex text layout services to the VCL
  81 // @author tse
  82 //
  83 class VCL_PLUGIN_PUBLIC GraphiteLayout : public SalLayout
  84 {
  85 public:
  86
  87     class Glyphs : public std::vector<GlyphItem>
  88     {
  89     public:
  90         typedef std::pair<Glyphs::const_iterator, Glyphs::const_iterator> iterator_pair_t;
  91
  92     };
  93
  94     mutable Glyphs          mvGlyphs;
  95     void clear();
  96
  97 private:
  98     const gr_face *         mpFace; // not owned by layout
  99     gr_font *               mpFont; // not owned by layout
 100     int                     mnSegCharOffset; // relative to ImplLayoutArgs::mpStr
 101     long                    mnWidth;
 102     std::vector<int>        mvChar2BaseGlyph;
 103     std::vector<int>        mvGlyph2Char;
 104     std::vector<int>        mvCharDxs;
 105     std::vector<int>        mvCharBreaks;
 106     float                   mfScaling;
 107     const grutils::GrFeatureParser * mpFeatures;
 108
 109 public:
 110     GraphiteLayout(const gr_face * pFace, gr_font * pFont = NULL,
 111         const grutils::GrFeatureParser * features = NULL) throw();
 112
 113     // used by upper layers
 114     virtual bool  LayoutText( ImplLayoutArgs& );    // first step of layout
 115     // split into two stages to allow dc to be restored on the segment
 116     gr_segment * CreateSegment(ImplLayoutArgs& rArgs);
 117     bool LayoutGlyphs(ImplLayoutArgs& rArgs, gr_segment * pSegment);
 118
 119     virtual void  AdjustLayout( ImplLayoutArgs& );  // adjusting positions
 120
 121     // methods using string indexing
 122     virtual int   GetTextBreak( long nMaxWidth, long nCharExtra=0, int nFactor=1 ) const;
 123     virtual long  FillDXArray( sal_Int32* pDXArray ) const;
 124     virtual void  ApplyDXArray(ImplLayoutArgs &rArgs, std::vector<int> & rDeltaWidth);
 125
 126     virtual void  GetCaretPositions( int nArraySize, sal_Int32* pCaretXArray ) const;
 127
 128     // methods using glyph indexing
 129     virtual int   GetNextGlyphs(int nLen, sal_GlyphId* pGlyphIdxAry, ::Point & rPos, int&,
 130             sal_Int32* pGlyphAdvAry = NULL, int* pCharPosAry = NULL,
 131             const PhysicalFontFace** pFallbackFonts = NULL ) const;
 132
 133     // used by glyph+font+script fallback
 134     virtual void    MoveGlyph( int nStart, long nNewXPos );
 135     virtual void    DropGlyph( int nStart );
 136     virtual void    Simplify( bool bIsBase );
 137
 138     // Dummy implementation so layout can be shared between Linux/Windows
 139     virtual void    DrawText(SalGraphics&) const {};
 140
 141     virtual ~GraphiteLayout() throw();
 142     void SetFont(gr_font * pFont) { mpFont = pFont; }
 143     gr_font * GetFont() { return mpFont; }
 144     void SetFeatures(grutils::GrFeatureParser * aFeature) { mpFeatures = aFeature; }
 145     void SetFontScale(float s) { mfScaling = s; };
 146     virtual sal_GlyphId getKashidaGlyph(int & width) = 0;
 147     void kashidaJustify(std::vector<int> & rDeltaWidth, sal_GlyphId, int width);
 148
 149     static const int EXTRA_CONTEXT_LENGTH;
 150 private:
 151     void expandOrCondense(ImplLayoutArgs &rArgs);
 152     void    fillFrom(gr_segment * rSeg, ImplLayoutArgs & rArgs, float fScaling);
 153
 154     float append(gr_segment * pSeg,
 155                 ImplLayoutArgs & rArgs,
 156                 const gr_slot * pSlot, float gOrigin,
 157                 float nextGlyphOrigin, float fScaling,
 158                 long & rDXOffset, bool bIsBase, int baseChar);
 159 };
 160
 161 #endif // INCLUDED_VCL_INC_GRAPHITE_LAYOUT_HXX
 162
 163 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */