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   HB_SCRIPT_OL_CHIKI,
 102   HB_SCRIPT_TAGALOG,
 103   HB_SCRIPT_MEETEI_MAYEK,
 104
 105   HB_SCRIPT_UNKNOWN, // EMOJI
 106   HB_SCRIPT_UNKNOWN, // SYMBOLS1
 107   HB_SCRIPT_UNKNOWN, // SYMBOLS2
 108   HB_SCRIPT_UNKNOWN, // SYMBOLS3
 109   HB_SCRIPT_UNKNOWN, // SYMBOLS4
 110   HB_SCRIPT_UNKNOWN, // SYMBOLS5
 111   HB_SCRIPT_UNKNOWN
 112 };
 113
 114 struct Shaping::Plugin
 115 {
 116   Plugin()
 117   : mFreeTypeLibrary( NULL ),
 118     mIndices(),
 119     mAdvance(),
 120     mCharacterMap(),
 121     mFontId( 0u )
 122   {
 123   }
 124
 125   ~Plugin()
 126   {
 127     FT_Done_FreeType( mFreeTypeLibrary );
 128   }
 129
 130   void Initialize()
 131   {
 132     int error = FT_Init_FreeType( &mFreeTypeLibrary );
 133     if( FT_Err_Ok != error )
 134     {
 135       DALI_LOG_ERROR( "FreeType Init error: %d\n", error );
 136     }
 137   }
 138
 139   Length Shape( const Character* const text,
 140                 Length numberOfCharacters,
 141                 FontId fontId,
 142                 Script script )
 143   {
 144     // Clear previoursly shaped texts.
 145     mIndices.Clear();
 146     mAdvance.Clear();
 147     mCharacterMap.Clear();
 148     mOffset.Clear();
 149     mFontId = fontId;
 150
 151     // Reserve some space to avoid reallocations.
 152     const Length numberOfGlyphs = static_cast<Length>( 1.3f * static_cast<float>( numberOfCharacters ) );
 153     mIndices.Reserve( numberOfGlyphs );
 154     mAdvance.Reserve( numberOfGlyphs );
 155     mCharacterMap.Reserve( numberOfGlyphs );
 156     mOffset.Reserve( 2u * numberOfGlyphs );
 157
 158     TextAbstraction::FontClient fontClient = TextAbstraction::FontClient::Get();
 159
 160     // Get the font's path file name from the font Id.
 161     FontDescription fontDescription;
 162     fontClient.GetDescription( fontId, fontDescription );
 163
 164     // Create a FreeType font's face.
 165     FT_Face face;
 166     FT_Error retVal = FT_New_Face( mFreeTypeLibrary, fontDescription.path.c_str(), 0u, &face );
 167     if( FT_Err_Ok != retVal )
 168     {
 169       DALI_LOG_ERROR( "Failed to open face: %s\n", fontDescription.path.c_str() );
 170       return 0u;
 171     }
 172
 173     unsigned int horizontalDpi = 0u;
 174     unsigned int verticalDpi = 0u;
 175     fontClient.GetDpi( horizontalDpi, verticalDpi );
 176
 177     FT_Set_Char_Size( face,
 178                       0u,
 179                       fontClient.GetPointSize( fontId ),
 180                       horizontalDpi,
 181                       verticalDpi );
 182
 183     /* Get our harfbuzz font struct */
 184     hb_font_t* harfBuzzFont;
 185     harfBuzzFont = hb_ft_font_create( face, NULL );
 186
 187     /* Create a buffer for harfbuzz to use */
 188     hb_buffer_t* harfBuzzBuffer = hb_buffer_create();
 189
 190     const bool rtlDirection = IsRightToLeftScript( script );
 191     hb_buffer_set_direction( harfBuzzBuffer,
 192                              rtlDirection ? HB_DIRECTION_RTL : HB_DIRECTION_LTR ); /* or LTR */
 193
 194     hb_buffer_set_script( harfBuzzBuffer,
 195                           SCRIPT_TO_HARFBUZZ[ script ] ); /* see hb-unicode.h */
 196
 197     hb_buffer_set_language( harfBuzzBuffer,
 198                             hb_language_from_string( DEFAULT_LANGUAGE,
 199                                                      DEFAULT_LANGUAGE_LENGTH ) );
 200
 201     /* Layout the text */
 202     hb_buffer_add_utf32( harfBuzzBuffer, text, numberOfCharacters, 0u, numberOfCharacters );
 203
 204     hb_shape( harfBuzzFont, harfBuzzBuffer, NULL, 0u );
 205
 206     /* Get glyph data */
 207     unsigned int glyphCount;
 208     hb_glyph_info_t* glyphInfo = hb_buffer_get_glyph_infos( harfBuzzBuffer, &glyphCount );
 209     hb_glyph_position_t *glyphPositions = hb_buffer_get_glyph_positions( harfBuzzBuffer, &glyphCount );
 210     const GlyphIndex lastGlyphIndex = glyphCount - 1u;
 211     for( GlyphIndex i = 0u; i < glyphCount; )
 212     {
 213       if( rtlDirection )
 214       {
 215         // If the direction is right to left, Harfbuzz retrieves the glyphs in the visual order.
 216         // The glyphs are needed in the logical order to layout the text in lines.
 217         // Do not change the order of the glyphs if they belong to the same cluster.
 218         GlyphIndex rtlIndex = lastGlyphIndex - i;
 219
 220         unsigned int cluster = glyphInfo[rtlIndex].cluster;
 221         unsigned int previousCluster = cluster;
 222         Length numberOfGlyphsInCluster = 0u;
 223
 224         while( ( cluster == previousCluster ) )
 225         {
 226           ++numberOfGlyphsInCluster;
 227           previousCluster = cluster;
 228
 229           if( rtlIndex > 0u )
 230           {
 231             --rtlIndex;
 232
 233             cluster = glyphInfo[rtlIndex].cluster;
 234           }
 235           else
 236           {
 237             break;
 238           }
 239         }
 240
 241         rtlIndex = lastGlyphIndex - ( i + ( numberOfGlyphsInCluster - 1u ) );
 242
 243         for( GlyphIndex j = 0u; j < numberOfGlyphsInCluster; ++j )
 244         {
 245           const GlyphIndex index = rtlIndex + j;
 246
 247           mIndices.PushBack( glyphInfo[index].codepoint );
 248           mAdvance.PushBack( floor( glyphPositions[index].x_advance * FROM_266 ) );
 249           mCharacterMap.PushBack( glyphInfo[index].cluster );
 250           mOffset.PushBack( floor( glyphPositions[index].x_offset * FROM_266 ) );
 251           mOffset.PushBack( floor( glyphPositions[index].y_offset * FROM_266 ) );
 252         }
 253
 254         i += numberOfGlyphsInCluster;
 255       }
 256       else
 257       {
 258         mIndices.PushBack( glyphInfo[i].codepoint );
 259         mAdvance.PushBack( floor( glyphPositions[i].x_advance * FROM_266 ) );
 260         mCharacterMap.PushBack( glyphInfo[i].cluster );
 261         mOffset.PushBack( floor( glyphPositions[i].x_offset * FROM_266 ) );
 262         mOffset.PushBack( floor( glyphPositions[i].y_offset * FROM_266 ) );
 263
 264         ++i;
 265       }
 266     }
 267
 268     /* Cleanup */
 269     hb_buffer_destroy( harfBuzzBuffer );
 270     hb_font_destroy( harfBuzzFont );
 271     FT_Done_Face( face );
 272
 273     return mIndices.Count();
 274   }
 275
 276   void GetGlyphs( GlyphInfo* glyphInfo,
 277                   CharacterIndex* glyphToCharacterMap )
 278   {
 279     Vector<CharacterIndex>::ConstIterator indicesIt = mIndices.Begin();
 280     Vector<float>::ConstIterator advanceIt = mAdvance.Begin();
 281     Vector<float>::ConstIterator offsetIt = mOffset.Begin();
 282     Vector<CharacterIndex>::ConstIterator characterMapIt = mCharacterMap.Begin();
 283
 284     for( GlyphIndex index = 0u, size = mIndices.Count(); index < size; ++index )
 285     {
 286       GlyphInfo& glyph = *( glyphInfo + index );
 287       CharacterIndex& glyphToCharacter = *( glyphToCharacterMap + index );
 288
 289       glyph.fontId = mFontId;
 290       glyph.index = *( indicesIt + index );
 291       glyph.advance = *( advanceIt + index );
 292
 293       const GlyphIndex offsetIndex = 2u * index;
 294       glyph.xBearing = *( offsetIt + offsetIndex );
 295       glyph.yBearing = *( offsetIt + offsetIndex + 1u );
 296
 297       glyphToCharacter = *( characterMapIt + index );
 298     }
 299   }
 300
 301   FT_Library             mFreeTypeLibrary;
 302
 303   Vector<CharacterIndex> mIndices;
 304   Vector<float>          mAdvance;
 305   Vector<float>          mOffset;
 306   Vector<CharacterIndex> mCharacterMap;
 307   FontId                 mFontId;
 308 };
 309
 310 Shaping::Shaping()
 311 : mPlugin( NULL )
 312 {
 313 }
 314
 315 Shaping::~Shaping()
 316 {
 317   delete mPlugin;
 318 }
 319
 320 TextAbstraction::Shaping Shaping::Get()
 321 {
 322   TextAbstraction::Shaping shapingHandle;
 323
 324   SingletonService service( SingletonService::Get() );
 325   if( service )
 326   {
 327     // Check whether the singleton is already created
 328     Dali::BaseHandle handle = service.GetSingleton( typeid( TextAbstraction::Shaping ) );
 329     if( handle )
 330     {
 331       // If so, downcast the handle
 332       Shaping* impl = dynamic_cast< Internal::Shaping* >( handle.GetObjectPtr() );
 333       shapingHandle = TextAbstraction::Shaping( impl );
 334     }
 335     else // create and register the object
 336     {
 337       shapingHandle = TextAbstraction::Shaping( new Shaping );
 338       service.Register( typeid( shapingHandle ), shapingHandle );
 339     }
 340   }
 341
 342   return shapingHandle;
 343 }
 344
 345 Length Shaping::Shape( const Character* const text,
 346                        Length numberOfCharacters,
 347                        FontId fontId,
 348                        Script script )
 349 {
 350   CreatePlugin();
 351
 352   return mPlugin->Shape( text,
 353                          numberOfCharacters,
 354                          fontId,
 355                          script );
 356 }
 357
 358 void Shaping::GetGlyphs( GlyphInfo* glyphInfo,
 359                          CharacterIndex* glyphToCharacterMap )
 360 {
 361   CreatePlugin();
 362
 363   mPlugin->GetGlyphs( glyphInfo,
 364                       glyphToCharacterMap );
 365 }
 366
 367 void Shaping::CreatePlugin()
 368 {
 369   if( !mPlugin )
 370   {
 371     mPlugin = new Plugin();
 372     mPlugin->Initialize();
 373   }
 374 }
 375
 376 } // namespace Internal
 377
 378 } // namespace TextAbstraction
 379
 380 } // namespace Dali