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 <graphite_static.hxx>
  35 #include <graphite2/Font.h>
  36 #include <graphite2/Segment.h>
  37 // Platform
  38 #include <vcl/dllapi.h>
  39
  40 #include "sallayout.hxx"
  41
  42 // Module
  43
  44 // Module type definitions and forward declarations.
  45 // SAL/VCL types
  46 class ServerFont;
  47 class PhysicalFontFace;
  48
  49 // Graphite types
  50 namespace grutils { class GrFeatureParser; }
  51
  52 class GraphiteFaceWrapper
  53 {
  54 public:
  55     typedef std::map<int, gr_font*> GrFontMap;
  56     GraphiteFaceWrapper(gr_face * pFace) : m_pFace(pFace) {}
  57     ~GraphiteFaceWrapper()
  58     {
  59         GrFontMap::iterator i = m_fonts.begin();
  60         while (i != m_fonts.end())
  61             gr_font_destroy((*i++).second);
  62         m_fonts.clear();
  63         gr_face_destroy(m_pFace);
  64     }
  65     const gr_face * face() const { return m_pFace; }
  66     gr_font * font(int ppm) const
  67     {
  68         GrFontMap::const_iterator i = m_fonts.find(ppm);
  69         if (i != m_fonts.end())
  70             return i->second;
  71         return NULL;
  72     };
  73     void addFont(int ppm, gr_font * pFont)
  74     {
  75         if (m_fonts[ppm])
  76             gr_font_destroy(m_fonts[ppm]);
  77         m_fonts[ppm] = pFont;
  78     }
  79 private:
  80     gr_face * m_pFace;
  81     GrFontMap m_fonts;
  82 };
  83
  84 // This class uses the SIL Graphite engine to provide complex text layout services to the VCL
  85 // @author tse
  86
  87 class VCL_PLUGIN_PUBLIC GraphiteLayout : public SalLayout
  88 {
  89 public:
  90
  91     class Glyphs : public std::vector<GlyphItem>
  92     {
  93     public:
  94         typedef std::pair<Glyphs::const_iterator, Glyphs::const_iterator> iterator_pair_t;
  95
  96     };
  97
  98     mutable Glyphs          mvGlyphs;
  99     void clear();
 100
 101 private:
 102     const gr_face *         mpFace; // not owned by layout
 103     gr_font *               mpFont; // not owned by layout
 104     int                     mnSegCharOffset; // relative to ImplLayoutArgs::mpStr
 105     long                    mnWidth;
 106     std::vector<int>        mvChar2BaseGlyph;
 107     std::vector<int>        mvGlyph2Char;
 108     std::vector<int>        mvCharDxs;
 109     std::vector<int>        mvCharBreaks;
 110     float                   mfScaling;
 111     const grutils::GrFeatureParser * mpFeatures;
 112
 113 public:
 114     GraphiteLayout(const gr_face * pFace, gr_font * pFont = NULL,
 115         const grutils::GrFeatureParser * features = NULL) throw();
 116
 117     // used by upper layers
 118     virtual bool  LayoutText( ImplLayoutArgs& ) SAL_OVERRIDE;    // first step of layout
 119     // split into two stages to allow dc to be restored on the segment
 120     gr_segment * CreateSegment(ImplLayoutArgs& rArgs);
 121     bool LayoutGlyphs(ImplLayoutArgs& rArgs, gr_segment * pSegment);
 122
 123     virtual void  AdjustLayout( ImplLayoutArgs& ) SAL_OVERRIDE;  // adjusting positions
 124
 125     // methods using string indexing
 126     virtual sal_Int32 GetTextBreak(long nMaxWidth, long nCharExtra=0, int nFactor=1) const SAL_OVERRIDE;
 127     virtual long  FillDXArray( sal_Int32* pDXArray ) const SAL_OVERRIDE;
 128     virtual void  ApplyDXArray(ImplLayoutArgs &rArgs, std::vector<int> & rDeltaWidth);
 129
 130     virtual void  GetCaretPositions( int nArraySize, sal_Int32* pCaretXArray ) const SAL_OVERRIDE;
 131
 132     // methods using glyph indexing
 133     virtual int   GetNextGlyphs(int nLen, sal_GlyphId* pGlyphIdxAry, ::Point & rPos, int&,
 134             sal_Int32* pGlyphAdvAry = NULL, int* pCharPosAry = NULL,
 135             const PhysicalFontFace** pFallbackFonts = NULL ) const SAL_OVERRIDE;
 136
 137     // used by glyph+font+script fallback
 138     virtual void    MoveGlyph( int nStart, long nNewXPos ) SAL_OVERRIDE;
 139     virtual void    DropGlyph( int nStart ) SAL_OVERRIDE;
 140     virtual void    Simplify( bool bIsBase ) SAL_OVERRIDE;
 141
 142     // Dummy implementation so layout can be shared between Linux/Windows
 143     virtual void    DrawText(SalGraphics&) const SAL_OVERRIDE {};
 144
 145     virtual ~GraphiteLayout() throw();
 146     void SetFont(gr_font * pFont) { mpFont = pFont; }
 147     gr_font * GetFont() { return mpFont; }
 148     void SetFeatures(grutils::GrFeatureParser * aFeature) { mpFeatures = aFeature; }
 149     void SetFontScale(float s) { mfScaling = s; };
 150     virtual sal_GlyphId getKashidaGlyph(int & width) = 0;
 151     void kashidaJustify(std::vector<int> & rDeltaWidth, sal_GlyphId, int width);
 152
 153     static const int EXTRA_CONTEXT_LENGTH;
 154 private:
 155     void expandOrCondense(ImplLayoutArgs &rArgs);
 156     void    fillFrom(gr_segment * rSeg, ImplLayoutArgs & rArgs, float fScaling);
 157
 158     float append(gr_segment * pSeg,
 159                 ImplLayoutArgs & rArgs,
 160                 const gr_slot * pSlot, float gOrigin,
 161                 float nextGlyphOrigin, float fScaling,
 162                 long & rDXOffset, bool bIsBase, int baseChar);
 163 };
 164
 165 #endif // INCLUDED_VCL_INC_GRAPHITE_LAYOUT_HXX
 166
 167 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */