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