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