2 * Copyright (c) 2015 Samsung Electronics Co., Ltd.
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
8 * http://www.apache.org/licenses/LICENSE-2.0
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.
19 #include "shaping-impl.h"
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>
28 #include <harfbuzz/hb.h>
29 #include <harfbuzz/hb-ft.h>
36 namespace TextAbstraction
42 const char* DEFAULT_LANGUAGE = "en";
43 const unsigned int DEFAULT_LANGUAGE_LENGTH = 2u;
44 const float FROM_266 = 1.0f / 64.0f;
46 const hb_script_t SCRIPT_TO_HARFBUZZ[] =
79 HB_SCRIPT_UNKNOWN, // EMOJI
83 struct Shaping::Plugin
86 : mFreeTypeLibrary( NULL ),
96 FT_Done_FreeType( mFreeTypeLibrary );
101 int error = FT_Init_FreeType( &mFreeTypeLibrary );
102 if( FT_Err_Ok != error )
104 DALI_LOG_ERROR( "FreeType Init error: %d\n", error );
108 Length Shape( const Character* const text,
109 Length numberOfCharacters,
113 // Clear previoursly shaped texts.
116 mCharacterMap.Clear();
120 // Reserve some space to avoid reallocations.
121 const Length numberOfGlyphs = static_cast<Length>( 1.3f * static_cast<float>( numberOfCharacters ) );
122 mIndices.Reserve( numberOfGlyphs );
123 mAdvance.Reserve( numberOfGlyphs );
124 mCharacterMap.Reserve( numberOfGlyphs );
125 mOffset.Reserve( 2u * numberOfGlyphs );
127 TextAbstraction::FontClient fontClient = TextAbstraction::FontClient::Get();
129 // Get the font's path file name from the font Id.
130 FontDescription fontDescription;
131 fontClient.GetDescription( fontId, fontDescription );
133 // Create a FreeType font's face.
135 FT_Error retVal = FT_New_Face( mFreeTypeLibrary, fontDescription.path.c_str(), 0u, &face );
136 if( FT_Err_Ok != retVal )
138 DALI_LOG_ERROR( "Failed to open face: %s\n", fontDescription.path.c_str() );
142 unsigned int horizontalDpi = 0u;
143 unsigned int verticalDpi = 0u;
144 fontClient.GetDpi( horizontalDpi, verticalDpi );
146 FT_Set_Char_Size( face,
148 fontClient.GetPointSize( fontId ),
152 /* Get our harfbuzz font struct */
153 hb_font_t* harfBuzzFont;
154 harfBuzzFont = hb_ft_font_create( face, NULL );
156 /* Create a buffer for harfbuzz to use */
157 hb_buffer_t* harfBuzzBuffer = hb_buffer_create();
159 const bool rtlDirection = IsRightToLeftScript( script );
160 hb_buffer_set_direction( harfBuzzBuffer,
161 rtlDirection ? HB_DIRECTION_RTL : HB_DIRECTION_LTR ); /* or LTR */
163 hb_buffer_set_script( harfBuzzBuffer,
164 SCRIPT_TO_HARFBUZZ[ script ] ); /* see hb-unicode.h */
166 hb_buffer_set_language( harfBuzzBuffer,
167 hb_language_from_string( DEFAULT_LANGUAGE,
168 DEFAULT_LANGUAGE_LENGTH ) );
170 /* Layout the text */
171 hb_buffer_add_utf32( harfBuzzBuffer, text, numberOfCharacters, 0u, numberOfCharacters );
173 hb_shape( harfBuzzFont, harfBuzzBuffer, NULL, 0u );
176 unsigned int glyphCount;
177 hb_glyph_info_t* glyphInfo = hb_buffer_get_glyph_infos( harfBuzzBuffer, &glyphCount );
178 hb_glyph_position_t *glyphPositions = hb_buffer_get_glyph_positions( harfBuzzBuffer, &glyphCount );
179 const GlyphIndex lastGlyphIndex = glyphCount - 1u;
180 for( GlyphIndex i = 0u; i < glyphCount; )
184 // If the direction is right to left, Harfbuzz retrieves the glyphs in the visual order.
185 // The glyphs are needed in the logical order to layout the text in lines.
186 // Do not change the order of the glyphs if they belong to the same cluster.
187 GlyphIndex rtlIndex = lastGlyphIndex - i;
189 unsigned int cluster = glyphInfo[rtlIndex].cluster;
190 unsigned int previousCluster = cluster;
191 Length numberOfGlyphsInCluster = 0u;
193 while( ( cluster == previousCluster ) )
195 ++numberOfGlyphsInCluster;
196 previousCluster = cluster;
202 cluster = glyphInfo[rtlIndex].cluster;
210 rtlIndex = lastGlyphIndex - ( i + ( numberOfGlyphsInCluster - 1u ) );
212 for( GlyphIndex j = 0u; j < numberOfGlyphsInCluster; ++j )
214 const GlyphIndex index = rtlIndex + j;
216 mIndices.PushBack( glyphInfo[index].codepoint );
217 mAdvance.PushBack( floor( glyphPositions[index].x_advance * FROM_266 ) );
218 mCharacterMap.PushBack( glyphInfo[index].cluster );
219 mOffset.PushBack( floor( glyphPositions[index].x_offset * FROM_266 ) );
220 mOffset.PushBack( floor( glyphPositions[index].y_offset * FROM_266 ) );
223 i += numberOfGlyphsInCluster;
227 mIndices.PushBack( glyphInfo[i].codepoint );
228 mAdvance.PushBack( floor( glyphPositions[i].x_advance * FROM_266 ) );
229 mCharacterMap.PushBack( glyphInfo[i].cluster );
230 mOffset.PushBack( floor( glyphPositions[i].x_offset * FROM_266 ) );
231 mOffset.PushBack( floor( glyphPositions[i].y_offset * FROM_266 ) );
238 hb_buffer_destroy( harfBuzzBuffer );
239 hb_font_destroy( harfBuzzFont );
240 FT_Done_Face( face );
242 return mIndices.Count();
245 void GetGlyphs( GlyphInfo* glyphInfo,
246 CharacterIndex* glyphToCharacterMap )
248 Vector<CharacterIndex>::ConstIterator indicesIt = mIndices.Begin();
249 Vector<float>::ConstIterator advanceIt = mAdvance.Begin();
250 Vector<float>::ConstIterator offsetIt = mOffset.Begin();
251 Vector<CharacterIndex>::ConstIterator characterMapIt = mCharacterMap.Begin();
253 for( GlyphIndex index = 0u, size = mIndices.Count(); index < size; ++index )
255 GlyphInfo& glyph = *( glyphInfo + index );
256 CharacterIndex& glyphToCharacter = *( glyphToCharacterMap + index );
258 glyph.fontId = mFontId;
259 glyph.index = *( indicesIt + index );
260 glyph.advance = *( advanceIt + index );
262 const GlyphIndex offsetIndex = 2u * index;
263 glyph.xBearing = *( offsetIt + offsetIndex );
264 glyph.yBearing = *( offsetIt + offsetIndex + 1u );
266 glyphToCharacter = *( characterMapIt + index );
270 FT_Library mFreeTypeLibrary;
272 Vector<CharacterIndex> mIndices;
273 Vector<float> mAdvance;
274 Vector<float> mOffset;
275 Vector<CharacterIndex> mCharacterMap;
289 TextAbstraction::Shaping Shaping::Get()
291 TextAbstraction::Shaping shapingHandle;
293 SingletonService service( SingletonService::Get() );
296 // Check whether the singleton is already created
297 Dali::BaseHandle handle = service.GetSingleton( typeid( TextAbstraction::Shaping ) );
300 // If so, downcast the handle
301 Shaping* impl = dynamic_cast< Internal::Shaping* >( handle.GetObjectPtr() );
302 shapingHandle = TextAbstraction::Shaping( impl );
304 else // create and register the object
306 shapingHandle = TextAbstraction::Shaping( new Shaping );
307 service.Register( typeid( shapingHandle ), shapingHandle );
311 return shapingHandle;
314 Length Shaping::Shape( const Character* const text,
315 Length numberOfCharacters,
321 return mPlugin->Shape( text,
327 void Shaping::GetGlyphs( GlyphInfo* glyphInfo,
328 CharacterIndex* glyphToCharacterMap )
332 mPlugin->GetGlyphs( glyphInfo,
333 glyphToCharacterMap );
336 void Shaping::CreatePlugin()
340 mPlugin = new Plugin();
341 mPlugin->Initialize();
345 } // namespace Internal
347 } // namespace TextAbstraction