dali-toolkit/internal/text/characters-helper-functions.cpp

   1 // FILE HEADER
   2 #include <dali-toolkit/internal/text/characters-helper-functions.h>
   3
   4 // INTERNAL INCLUDES
   5 #include <dali-toolkit/internal/text/emoji-helper.h>
   6
   7 namespace Dali
   8 {
   9 namespace Toolkit
  10 {
  11 namespace Text
  12 {
  13 CharacterRun RetrieveClusteredCharactersOfCharacterIndex(const VisualModelPtr&  visualModel,
  14                                                          const LogicalModelPtr& logicalModel,
  15                                                          const CharacterIndex&  characterIndex)
  16 {
  17   // Initialization
  18   CharacterRun clusteredCharacters;
  19   clusteredCharacters.characterIndex     = characterIndex;
  20   clusteredCharacters.numberOfCharacters = 1u;
  21
  22   const GlyphIndex* const     charactersToGlyphBuffer  = visualModel->mCharactersToGlyph.Begin();
  23   const Length* const         charactersPerGlyphBuffer = visualModel->mCharactersPerGlyph.Begin();
  24   const CharacterIndex* const glyphsToCharacters       = visualModel->mGlyphsToCharacters.Begin();
  25
  26   GlyphIndex glyphIndex               = *(charactersToGlyphBuffer + characterIndex);
  27   Length     actualNumberOfCharacters = *(charactersPerGlyphBuffer + glyphIndex);
  28
  29   if(actualNumberOfCharacters > 1u)
  30   {
  31     const Script script = logicalModel->GetScript(characterIndex);
  32     // Prevents to break the Latin ligatures like fi, ff, or Arabic ﻻ, ...
  33     // Keep actual index of character as is. Because these characters cannot be clustered.
  34
  35     if(!HasLigatureMustBreak(script))
  36     {
  37       clusteredCharacters.numberOfCharacters = actualNumberOfCharacters;
  38       clusteredCharacters.characterIndex     = *(glyphsToCharacters + glyphIndex); // firstCharacterIndex
  39     }
  40   }
  41   else
  42   {
  43     while(0u == actualNumberOfCharacters)
  44     {
  45       ++glyphIndex;
  46       actualNumberOfCharacters = *(charactersPerGlyphBuffer + glyphIndex);
  47     }
  48
  49     clusteredCharacters.characterIndex     = *(glyphsToCharacters + glyphIndex); // firstCharacterIndex
  50     clusteredCharacters.numberOfCharacters = actualNumberOfCharacters;
  51   }
  52
  53   return clusteredCharacters;
  54 }
  55
  56 } // namespace Text
  57
  58 } // namespace Toolkit
  59
  60 } // namespace Dali