text/dali/internal/text-abstraction/bidirectional-support-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 "bidirectional-support-impl.h"
  20
  21 // INTERNAL INCLUDES
  22 #include <singleton-service-impl.h>
  23
  24 // EXTERNAL INCLUDES
  25 #include <memory.h>
  26 #include <fribidi/fribidi.h>
  27
  28 namespace Dali
  29 {
  30
  31 namespace TextAbstraction
  32 {
  33
  34 namespace Internal
  35 {
  36
  37 struct BidirectionalSupport::BidirectionalInfo
  38 {
  39   FriBidiCharType* characterTypes;      ///< The type of each character (right, left, neutral, ...)
  40   FriBidiLevel*    embeddedLevels;      ///< Embedded levels.
  41   FriBidiParType   paragraphDirection;  ///< The paragraph's direction.
  42 };
  43
  44 BidirectionalSupport::BidirectionalSupport()
  45 : mPlugin( NULL ),
  46   mParagraphBidirectionalInfo(),
  47   mFreeIndices()
  48 {
  49 }
  50
  51 BidirectionalSupport::~BidirectionalSupport()
  52 {
  53   // free all resources.
  54   for( Vector<BidirectionalInfo*>::Iterator it = mParagraphBidirectionalInfo.Begin(),
  55          endIt = mParagraphBidirectionalInfo.End();
  56        it != endIt;
  57        ++it )
  58   {
  59     BidirectionalInfo* info = *it;
  60
  61     free( info->embeddedLevels );
  62     free( info->characterTypes );
  63     delete info;
  64   }
  65 }
  66
  67 TextAbstraction::BidirectionalSupport BidirectionalSupport::Get()
  68 {
  69   TextAbstraction::BidirectionalSupport bidirectionalSupportHandle;
  70
  71   SingletonService service( SingletonService::Get() );
  72   if( service )
  73   {
  74     // Check whether the singleton is already created
  75     BaseHandle handle = service.GetSingleton( typeid( TextAbstraction::BidirectionalSupport ) );
  76     if(handle)
  77     {
  78       // If so, downcast the handle
  79       BidirectionalSupport* impl = dynamic_cast< Internal::BidirectionalSupport* >( handle.GetObjectPtr() );
  80       bidirectionalSupportHandle = TextAbstraction::BidirectionalSupport( impl );
  81     }
  82     else // create and register the object
  83     {
  84       bidirectionalSupportHandle = TextAbstraction::BidirectionalSupport( new BidirectionalSupport );
  85       service.Register( typeid( bidirectionalSupportHandle ), bidirectionalSupportHandle );
  86     }
  87   }
  88
  89   return bidirectionalSupportHandle;
  90 }
  91
  92 BidiInfoIndex BidirectionalSupport::CreateInfo( const Character* const paragraph,
  93                                                 Length numberOfCharacters )
  94 {
  95   // Reserve memory for the paragraph's bidirectional info.
  96   BidirectionalInfo* bidirectionalInfo = new BidirectionalInfo();
  97
  98   bidirectionalInfo->characterTypes = reinterpret_cast<FriBidiCharType*>( malloc( numberOfCharacters * sizeof( FriBidiCharType ) ) );
  99   bidirectionalInfo->embeddedLevels = reinterpret_cast<FriBidiLevel*>( malloc( numberOfCharacters * sizeof( FriBidiLevel ) ) );
 100
 101   // Retrieve the type of each character..
 102   fribidi_get_bidi_types( paragraph, numberOfCharacters, bidirectionalInfo->characterTypes );
 103
 104   // Retrieve the paragraph's direction.
 105   bidirectionalInfo->paragraphDirection = fribidi_get_par_direction( paragraph, numberOfCharacters );
 106
 107   // Retrieve the embedding levels.
 108   fribidi_get_par_embedding_levels( paragraph, numberOfCharacters, &bidirectionalInfo->paragraphDirection, bidirectionalInfo->embeddedLevels );
 109
 110   // Store the bidirectional info and return the index.
 111   BidiInfoIndex index = 0u;
 112   const std::size_t numberOfItems = mFreeIndices.Count();
 113   if( numberOfItems != 0u )
 114   {
 115     Vector<BidiInfoIndex>::Iterator it = mFreeIndices.End() - 1u;
 116
 117     index = *it;
 118
 119     mFreeIndices.Remove( it );
 120
 121     *( mParagraphBidirectionalInfo.Begin() + index ) = bidirectionalInfo;
 122   }
 123   else
 124   {
 125     index = static_cast<BidiInfoIndex>( numberOfItems );
 126
 127     mParagraphBidirectionalInfo.PushBack( bidirectionalInfo );
 128   }
 129
 130   return index;
 131 }
 132
 133 void BidirectionalSupport::DestroyInfo( BidiInfoIndex bidiInfoIndex )
 134 {
 135   if( bidiInfoIndex >= mParagraphBidirectionalInfo.Count() )
 136   {
 137     return;
 138   }
 139
 140   // Retrieve the paragraph's bidirectional info.
 141   Vector<BidirectionalInfo*>::Iterator it = mParagraphBidirectionalInfo.Begin() + bidiInfoIndex;
 142   BidirectionalInfo* bidirectionalInfo = *it;
 143
 144   if( NULL != bidirectionalInfo )
 145   {
 146     // Free resources and destroy the container.
 147     free( bidirectionalInfo->embeddedLevels );
 148     free( bidirectionalInfo->characterTypes );
 149     delete bidirectionalInfo;
 150
 151     *it = NULL;
 152   }
 153
 154   // Add the index to the free indices vector.
 155   mFreeIndices.PushBack( bidiInfoIndex );
 156 }
 157
 158 void BidirectionalSupport::Reorder( BidiInfoIndex bidiInfoIndex,
 159                                     CharacterIndex firstCharacterIndex,
 160                                     Length numberOfCharacters,
 161                                     CharacterIndex* visualToLogicalMap )
 162 {
 163   const FriBidiFlags flags = FRIBIDI_FLAGS_DEFAULT | FRIBIDI_FLAGS_ARABIC;
 164
 165   // Retrieve the paragraph's bidirectional info.
 166   const BidirectionalInfo* const bidirectionalInfo = *( mParagraphBidirectionalInfo.Begin() + bidiInfoIndex );
 167
 168   // Initialize the visual to logical mapping table to the identity. Otherwise fribidi_reorder_line fails to retrieve a valid mapping table.
 169   for( CharacterIndex index = 0u; index < numberOfCharacters; ++index )
 170   {
 171     visualToLogicalMap[ index ] = index;
 172   }
 173
 174   // Copy embedded levels as fribidi_reorder_line() may change them.
 175   const uint32_t embeddedLevelsSize = numberOfCharacters * sizeof( FriBidiLevel );
 176   FriBidiLevel* embeddedLevels = reinterpret_cast<FriBidiLevel*>( malloc( embeddedLevelsSize ) );
 177   memcpy( embeddedLevels, bidirectionalInfo->embeddedLevels + firstCharacterIndex,  embeddedLevelsSize );
 178
 179   // Reorder the line.
 180   fribidi_reorder_line( flags,
 181                         bidirectionalInfo->characterTypes + firstCharacterIndex,
 182                         numberOfCharacters,
 183                         0u,
 184                         bidirectionalInfo->paragraphDirection,
 185                         embeddedLevels,
 186                         NULL,
 187                         reinterpret_cast<FriBidiStrIndex*>( visualToLogicalMap ) );
 188
 189   // Free resources.
 190   free( embeddedLevels );
 191 }
 192
 193 } // namespace Internal
 194
 195 } // namespace TextAbstraction
 196
 197 } // namespace Dali