text/dali/internal/text-abstraction/shaping-impl.cpp

   1 /*
   2  * Copyright (c) 2015 Samsung Electronics Co., Ltd.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  * http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  *
  16  */
  17
  18 // CLASS  HEADER
  19 #include "shaping-impl.h"
  20
  21 // INTERNAL INCLUDES
  22 #include <singleton-service-impl.h>
  23 #include <dali/devel-api/text-abstraction/font-client.h>
  24 #include <dali/devel-api/text-abstraction/glyph-info.h>
  25 #include <dali/integration-api/debug.h>
  26
  27 // EXTERNAL INCLUDES
  28 #include <harfbuzz/hb.h>
  29 #include <harfbuzz/hb-ft.h>
  30
  31 #include <ft2build.h>
  32
  33 namespace Dali
  34 {
  35
  36 namespace TextAbstraction
  37 {
  38
  39 namespace Internal
  40 {
  41
  42 const char*        DEFAULT_LANGUAGE = "en";
  43 const unsigned int DEFAULT_LANGUAGE_LENGTH = 2u;
  44 const float        FROM_266 = 1.0f / 64.0f;
  45
  46 const hb_script_t SCRIPT_TO_HARFBUZZ[] =
  47 {
  48   HB_SCRIPT_COMMON,
  49
  50   HB_SCRIPT_COMMON, // ASCII_DIGITS
  51   HB_SCRIPT_COMMON, // ASCII_PS
  52
  53   HB_SCRIPT_COMMON, // C1_CONTROLS
  54   HB_SCRIPT_COMMON, // C1_PS
  55   HB_SCRIPT_COMMON, // C1_MATH
  56   HB_SCRIPT_COMMON, // SML_P
  57   HB_SCRIPT_COMMON, // PHONETIC_U
  58   HB_SCRIPT_COMMON, // PHONETIC_SS
  59   HB_SCRIPT_COMMON, // NUMERIC_SS
  60   HB_SCRIPT_COMMON, // LETTER_LIKE
  61   HB_SCRIPT_COMMON, // NUMBER_FORMS
  62   HB_SCRIPT_COMMON, // FRACTIONS_NF
  63   HB_SCRIPT_COMMON, // NON_LATIN_LED
  64   HB_SCRIPT_COMMON, // HWFW_S
  65
  66   HB_SCRIPT_CYRILLIC,
  67   HB_SCRIPT_GREEK,
  68   HB_SCRIPT_LATIN,
  69
  70   HB_SCRIPT_ARABIC,
  71   HB_SCRIPT_HEBREW,
  72
  73   HB_SCRIPT_ARMENIAN,
  74   HB_SCRIPT_GEORGIAN,
  75
  76   HB_SCRIPT_HAN,
  77   HB_SCRIPT_HANGUL,
  78   HB_SCRIPT_HIRAGANA,
  79   HB_SCRIPT_KATAKANA,
  80   HB_SCRIPT_BOPOMOFO,
  81
  82   HB_SCRIPT_BENGALI,
  83   HB_SCRIPT_MYANMAR,
  84   HB_SCRIPT_DEVANAGARI,
  85   HB_SCRIPT_GUJARATI,
  86   HB_SCRIPT_GURMUKHI,
  87   HB_SCRIPT_KANNADA,
  88   HB_SCRIPT_MALAYALAM,
  89   HB_SCRIPT_ORIYA,
  90   HB_SCRIPT_SINHALA,
  91   HB_SCRIPT_TAMIL,
  92   HB_SCRIPT_TELUGU,
  93
  94   HB_SCRIPT_LAO,
  95   HB_SCRIPT_THAI,
  96   HB_SCRIPT_KHMER,
  97   HB_SCRIPT_JAVANESE,
  98   HB_SCRIPT_SUNDANESE,
  99
 100   HB_SCRIPT_ETHIOPIC,
 101
 102   HB_SCRIPT_UNKNOWN, // EMOJI
 103   HB_SCRIPT_UNKNOWN, // SYMBOLS1
 104   HB_SCRIPT_UNKNOWN, // SYMBOLS2
 105   HB_SCRIPT_UNKNOWN, // SYMBOLS3
 106   HB_SCRIPT_UNKNOWN, // SYMBOLS4
 107   HB_SCRIPT_UNKNOWN, // SYMBOLS5
 108   HB_SCRIPT_UNKNOWN
 109 };
 110
 111 struct Shaping::Plugin
 112 {
 113   Plugin()
 114   : mFreeTypeLibrary( NULL ),
 115     mIndices(),
 116     mAdvance(),
 117     mCharacterMap(),
 118     mFontId( 0u )
 119   {
 120   }
 121
 122   ~Plugin()
 123   {
 124     FT_Done_FreeType( mFreeTypeLibrary );
 125   }
 126
 127   void Initialize()
 128   {
 129     int error = FT_Init_FreeType( &mFreeTypeLibrary );
 130     if( FT_Err_Ok != error )
 131     {
 132       DALI_LOG_ERROR( "FreeType Init error: %d\n", error );
 133     }
 134   }
 135
 136   Length Shape( const Character* const text,
 137                 Length numberOfCharacters,
 138                 FontId fontId,
 139                 Script script )
 140   {
 141     // Clear previoursly shaped texts.
 142     mIndices.Clear();
 143     mAdvance.Clear();
 144     mCharacterMap.Clear();
 145     mOffset.Clear();
 146     mFontId = fontId;
 147
 148     // Reserve some space to avoid reallocations.
 149     const Length numberOfGlyphs = static_cast<Length>( 1.3f * static_cast<float>( numberOfCharacters ) );
 150     mIndices.Reserve( numberOfGlyphs );
 151     mAdvance.Reserve( numberOfGlyphs );
 152     mCharacterMap.Reserve( numberOfGlyphs );
 153     mOffset.Reserve( 2u * numberOfGlyphs );
 154
 155     TextAbstraction::FontClient fontClient = TextAbstraction::FontClient::Get();
 156
 157     // Get the font's path file name from the font Id.
 158     FontDescription fontDescription;
 159     fontClient.GetDescription( fontId, fontDescription );
 160
 161     // Create a FreeType font's face.
 162     FT_Face face;
 163     FT_Error retVal = FT_New_Face( mFreeTypeLibrary, fontDescription.path.c_str(), 0u, &face );
 164     if( FT_Err_Ok != retVal )
 165     {
 166       DALI_LOG_ERROR( "Failed to open face: %s\n", fontDescription.path.c_str() );
 167       return 0u;
 168     }
 169
 170     unsigned int horizontalDpi = 0u;
 171     unsigned int verticalDpi = 0u;
 172     fontClient.GetDpi( horizontalDpi, verticalDpi );
 173
 174     FT_Set_Char_Size( face,
 175                       0u,
 176                       fontClient.GetPointSize( fontId ),
 177                       horizontalDpi,
 178                       verticalDpi );
 179
 180     /* Get our harfbuzz font struct */
 181     hb_font_t* harfBuzzFont;
 182     harfBuzzFont = hb_ft_font_create( face, NULL );
 183
 184     /* Create a buffer for harfbuzz to use */
 185     hb_buffer_t* harfBuzzBuffer = hb_buffer_create();
 186
 187     const bool rtlDirection = IsRightToLeftScript( script );
 188     hb_buffer_set_direction( harfBuzzBuffer,
 189                              rtlDirection ? HB_DIRECTION_RTL : HB_DIRECTION_LTR ); /* or LTR */
 190
 191     hb_buffer_set_script( harfBuzzBuffer,
 192                           SCRIPT_TO_HARFBUZZ[ script ] ); /* see hb-unicode.h */
 193
 194     hb_buffer_set_language( harfBuzzBuffer,
 195                             hb_language_from_string( DEFAULT_LANGUAGE,
 196                                                      DEFAULT_LANGUAGE_LENGTH ) );
 197
 198     /* Layout the text */
 199     hb_buffer_add_utf32( harfBuzzBuffer, text, numberOfCharacters, 0u, numberOfCharacters );
 200
 201     hb_shape( harfBuzzFont, harfBuzzBuffer, NULL, 0u );
 202
 203     /* Get glyph data */
 204     unsigned int glyphCount;
 205     hb_glyph_info_t* glyphInfo = hb_buffer_get_glyph_infos( harfBuzzBuffer, &glyphCount );
 206     hb_glyph_position_t *glyphPositions = hb_buffer_get_glyph_positions( harfBuzzBuffer, &glyphCount );
 207     const GlyphIndex lastGlyphIndex = glyphCount - 1u;
 208     for( GlyphIndex i = 0u; i < glyphCount; )
 209     {
 210       if( rtlDirection )
 211       {
 212         // If the direction is right to left, Harfbuzz retrieves the glyphs in the visual order.
 213         // The glyphs are needed in the logical order to layout the text in lines.
 214         // Do not change the order of the glyphs if they belong to the same cluster.
 215         GlyphIndex rtlIndex = lastGlyphIndex - i;
 216
 217         unsigned int cluster = glyphInfo[rtlIndex].cluster;
 218         unsigned int previousCluster = cluster;
 219         Length numberOfGlyphsInCluster = 0u;
 220
 221         while( ( cluster == previousCluster ) )
 222         {
 223           ++numberOfGlyphsInCluster;
 224           previousCluster = cluster;
 225
 226           if( rtlIndex > 0u )
 227           {
 228             --rtlIndex;
 229
 230             cluster = glyphInfo[rtlIndex].cluster;
 231           }
 232           else
 233           {
 234             break;
 235           }
 236         }
 237
 238         rtlIndex = lastGlyphIndex - ( i + ( numberOfGlyphsInCluster - 1u ) );
 239
 240         for( GlyphIndex j = 0u; j < numberOfGlyphsInCluster; ++j )
 241         {
 242           const GlyphIndex index = rtlIndex + j;
 243
 244           mIndices.PushBack( glyphInfo[index].codepoint );
 245           mAdvance.PushBack( floor( glyphPositions[index].x_advance * FROM_266 ) );
 246           mCharacterMap.PushBack( glyphInfo[index].cluster );
 247           mOffset.PushBack( floor( glyphPositions[index].x_offset * FROM_266 ) );
 248           mOffset.PushBack( floor( glyphPositions[index].y_offset * FROM_266 ) );
 249         }
 250
 251         i += numberOfGlyphsInCluster;
 252       }
 253       else
 254       {
 255         mIndices.PushBack( glyphInfo[i].codepoint );
 256         mAdvance.PushBack( floor( glyphPositions[i].x_advance * FROM_266 ) );
 257         mCharacterMap.PushBack( glyphInfo[i].cluster );
 258         mOffset.PushBack( floor( glyphPositions[i].x_offset * FROM_266 ) );
 259         mOffset.PushBack( floor( glyphPositions[i].y_offset * FROM_266 ) );
 260
 261         ++i;
 262       }
 263     }
 264
 265     /* Cleanup */
 266     hb_buffer_destroy( harfBuzzBuffer );
 267     hb_font_destroy( harfBuzzFont );
 268     FT_Done_Face( face );
 269
 270     return mIndices.Count();
 271   }
 272
 273   void GetGlyphs( GlyphInfo* glyphInfo,
 274                   CharacterIndex* glyphToCharacterMap )
 275   {
 276     Vector<CharacterIndex>::ConstIterator indicesIt = mIndices.Begin();
 277     Vector<float>::ConstIterator advanceIt = mAdvance.Begin();
 278     Vector<float>::ConstIterator offsetIt = mOffset.Begin();
 279     Vector<CharacterIndex>::ConstIterator characterMapIt = mCharacterMap.Begin();
 280
 281     for( GlyphIndex index = 0u, size = mIndices.Count(); index < size; ++index )
 282     {
 283       GlyphInfo& glyph = *( glyphInfo + index );
 284       CharacterIndex& glyphToCharacter = *( glyphToCharacterMap + index );
 285
 286       glyph.fontId = mFontId;
 287       glyph.index = *( indicesIt + index );
 288       glyph.advance = *( advanceIt + index );
 289
 290       const GlyphIndex offsetIndex = 2u * index;
 291       glyph.xBearing = *( offsetIt + offsetIndex );
 292       glyph.yBearing = *( offsetIt + offsetIndex + 1u );
 293
 294       glyphToCharacter = *( characterMapIt + index );
 295     }
 296   }
 297
 298   FT_Library             mFreeTypeLibrary;
 299
 300   Vector<CharacterIndex> mIndices;
 301   Vector<float>          mAdvance;
 302   Vector<float>          mOffset;
 303   Vector<CharacterIndex> mCharacterMap;
 304   FontId                 mFontId;
 305 };
 306
 307 Shaping::Shaping()
 308 : mPlugin( NULL )
 309 {
 310 }
 311
 312 Shaping::~Shaping()
 313 {
 314   delete mPlugin;
 315 }
 316
 317 TextAbstraction::Shaping Shaping::Get()
 318 {
 319   TextAbstraction::Shaping shapingHandle;
 320
 321   SingletonService service( SingletonService::Get() );
 322   if( service )
 323   {
 324     // Check whether the singleton is already created
 325     Dali::BaseHandle handle = service.GetSingleton( typeid( TextAbstraction::Shaping ) );
 326     if( handle )
 327     {
 328       // If so, downcast the handle
 329       Shaping* impl = dynamic_cast< Internal::Shaping* >( handle.GetObjectPtr() );
 330       shapingHandle = TextAbstraction::Shaping( impl );
 331     }
 332     else // create and register the object
 333     {
 334       shapingHandle = TextAbstraction::Shaping( new Shaping );
 335       service.Register( typeid( shapingHandle ), shapingHandle );
 336     }
 337   }
 338
 339   return shapingHandle;
 340 }
 341
 342 Length Shaping::Shape( const Character* const text,
 343                        Length numberOfCharacters,
 344                        FontId fontId,
 345                        Script script )
 346 {
 347   CreatePlugin();
 348
 349   return mPlugin->Shape( text,
 350                          numberOfCharacters,
 351                          fontId,
 352                          script );
 353 }
 354
 355 void Shaping::GetGlyphs( GlyphInfo* glyphInfo,
 356                          CharacterIndex* glyphToCharacterMap )
 357 {
 358   CreatePlugin();
 359
 360   mPlugin->GetGlyphs( glyphInfo,
 361                       glyphToCharacterMap );
 362 }
 363
 364 void Shaping::CreatePlugin()
 365 {
 366   if( !mPlugin )
 367   {
 368     mPlugin = new Plugin();
 369     mPlugin->Initialize();
 370   }
 371 }
 372
 373 } // namespace Internal
 374
 375 } // namespace TextAbstraction
 376
 377 } // namespace Dali