X-Git-Url: http://review.tizen.org/git/?p=platform%2Fcore%2Fuifw%2Fdali-toolkit.git;a=blobdiff_plain;f=dali-toolkit%2Finternal%2Ftext%2Flayouts%2Flayout-engine.cpp;h=b018ed159081655e936b27edd5ab073500d51908;hp=ac2c53ff85a60df602f605e819a08430bf1c85dd;hb=5064025f6246c31c82cd1531084b639ac9c3237d;hpb=830f03638ec6ecd3b12ba3d9eb6419fdb3a3db09

diff --git a/dali-toolkit/internal/text/layouts/layout-engine.cpp b/dali-toolkit/internal/text/layouts/layout-engine.cpp
index ac2c53f..b018ed1 100644
--- a/dali-toolkit/internal/text/layouts/layout-engine.cpp
+++ b/dali-toolkit/internal/text/layouts/layout-engine.cpp
@@ -19,12 +19,14 @@
 #include <dali-toolkit/internal/text/layouts/layout-engine.h>
 
 // EXTERNAL INCLUDES
+#include <limits>
 #include <dali/public-api/math/vector2.h>
-#include <dali/public-api/text-abstraction/font-client.h>
+#include <dali/devel-api/text-abstraction/font-client.h>
+#include <dali/integration-api/debug.h>
 
 // INTERNAL INCLUDES
-#include <dali-toolkit/internal/text/logical-model.h>
-#include <dali-toolkit/internal/text/visual-model.h>
+#include <dali-toolkit/internal/text/layouts/layout-parameters.h>
+#include <dali-toolkit/internal/text/bidirectional-line-info-run.h>
 
 namespace Dali
 {
@@ -35,179 +37,600 @@ namespace Toolkit
 namespace Text
 {
 
+namespace
+{
+
+#if defined(DEBUG_ENABLED)
+  Debug::Filter* gLogFilter = Debug::Filter::New(Debug::Concise, true, "LOG_TEXT_LAYOUT");
+#endif
+
+const float MAX_FLOAT = std::numeric_limits<float>::max();
+const bool RTL = true;
+
+} //namespace
+
+/**
+ * @brief Stores temporary layout info of the line.
+ */
+struct LineLayout
+{
+  LineLayout()
+  : glyphIndex( 0u ),
+    characterIndex( 0u ),
+    numberOfGlyphs( 0u ),
+    numberOfCharacters( 0u ),
+    length( 0.f ),
+    widthAdvanceDiff( 0.f ),
+    wsLengthEndOfLine( 0.f ),
+    ascender( 0.f ),
+    descender( MAX_FLOAT )
+  {}
+
+  ~LineLayout()
+  {}
+
+  void Clear()
+  {
+    glyphIndex = 0u;
+    characterIndex = 0u;
+    numberOfGlyphs = 0u;
+    numberOfCharacters = 0u;
+    length = 0.f;
+    widthAdvanceDiff = 0.f;
+    wsLengthEndOfLine = 0.f;
+    ascender = 0.f;
+    descender = MAX_FLOAT;
+  }
+
+  GlyphIndex     glyphIndex;         ///< Index of the first glyph to be laid-out.
+  CharacterIndex characterIndex;     ///< Index of the first character to be laid-out.
+  Length         numberOfGlyphs;     ///< The number of glyph which fit in one line.
+  Length         numberOfCharacters; ///< The number of characters which fit in one line.
+  float          length;             ///< The length of the glyphs which fit in one line.
+  float          widthAdvanceDiff;   ///< The difference between the xBearing + width and the advance of the last glyph.
+  float          wsLengthEndOfLine;  ///< The length of the white spaces at the end of the line.
+  float          ascender;           ///< The maximum ascender of all fonts in the line.
+  float          descender;          ///< The minimum descender of all fonts in the line.
+};
+
 struct LayoutEngine::Impl
 {
   Impl()
-  : mLayout( LayoutEngine::SINGLE_LINE_BOX )
+  : mLayout( LayoutEngine::SINGLE_LINE_BOX ),
+    mHorizontalAlignment( LayoutEngine::HORIZONTAL_ALIGN_BEGIN ),
+    mVerticalAlignment( LayoutEngine::VERTICAL_ALIGN_TOP ),
+    mEllipsisEnabled( false )
   {
     mFontClient = TextAbstraction::FontClient::Get();
   }
 
-  void UpdateVisualModel( const Vector2& boundingBox,
-                          const Vector<GlyphInfo>& glyphs,
-                          const Vector<CharacterIndex>& characterIndices,
-                          const Vector<Length>& charactersPerGlyph,
-                          VisualModel& visualModel )
+  /**
+   * @brief Updates the line ascender and descender with the metrics of a new font.
+   *
+   * @param[in] fontId The id of the new font.
+   * @param[in,out] lineLayout The line layout.
+   */
+  void UpdateLineHeight( FontId fontId, LineLayout& lineLayout )
   {
-    // TODO Switch between different layouts
+    Text::FontMetrics fontMetrics;
+    mFontClient.GetFontMetrics( fontId, fontMetrics );
 
-    visualModel.SetGlyphs( &glyphs[0],
-                           &characterIndices[0],
-                           &charactersPerGlyph[0],
-                           glyphs.Count() );
+    // Sets the maximum ascender.
+    if( fontMetrics.ascender > lineLayout.ascender )
+    {
+      lineLayout.ascender = fontMetrics.ascender;
+    }
 
-    UpdateGlyphPositions( boundingBox, visualModel );
+    // Sets the minimum descender.
+    if( fontMetrics.descender < lineLayout.descender )
+    {
+      lineLayout.descender = fontMetrics.descender;
+    }
   }
 
-  void UpdateGlyphPositions( const Vector2& boundingBox, VisualModel& visualModel )
+  /**
+   * @brief Merges a temporary line layout into the line layout.
+   *
+   * @param[in,out] lineLayout The line layout.
+   * @param[in] tmpLineLayout A temporary line layout.
+   */
+  void MergeLineLayout( LineLayout& lineLayout,
+                        const LineLayout& tmpLineLayout )
   {
-    if( LayoutEngine::SINGLE_LINE_BOX == mLayout )
+    lineLayout.numberOfCharacters += tmpLineLayout.numberOfCharacters;
+    lineLayout.numberOfGlyphs += tmpLineLayout.numberOfGlyphs;
+    lineLayout.length += tmpLineLayout.length;
+
+    if( 0.f < tmpLineLayout.length )
     {
-      SingleLineLayout( boundingBox, visualModel );
+      lineLayout.length += lineLayout.wsLengthEndOfLine;
+
+      lineLayout.wsLengthEndOfLine = tmpLineLayout.wsLengthEndOfLine;
+      lineLayout.widthAdvanceDiff = tmpLineLayout.widthAdvanceDiff;
     }
     else
     {
-      MultiLineLayout( boundingBox, visualModel );
+      lineLayout.wsLengthEndOfLine += tmpLineLayout.wsLengthEndOfLine;
+    }
+
+    if( tmpLineLayout.ascender > lineLayout.ascender )
+    {
+      lineLayout.ascender = tmpLineLayout.ascender;
+    }
+
+    if( tmpLineLayout.descender < lineLayout.descender )
+    {
+      lineLayout.descender = tmpLineLayout.descender;
     }
   }
 
-  // TODO - Rewrite this to handle bidi
-  void SingleLineLayout( const Vector2& boundingBox, VisualModel& visualModel )
+  /**
+   * Retrieves the line layout for a given box width.
+   *
+   * @param[in] parameters The layout parameters.
+   * @param[out] lineLayout The line layout.
+   * @param[in] completelyFill Whether to completely fill the line ( even if the last word exceeds the boundaries ).
+   */
+  void GetLineLayoutForBox( const LayoutParameters& parameters,
+                            LineLayout& lineLayout,
+                            bool completelyFill )
   {
-    Length glyphCount = visualModel.GetNumberOfGlyphs();
+    DALI_LOG_INFO( gLogFilter, Debug::Verbose, "-->GetLineLayoutForBox\n" );
+    DALI_LOG_INFO( gLogFilter, Debug::Verbose, "  initial glyph index : %d\n", lineLayout.glyphIndex );
+    // Stores temporary line layout which has not been added to the final line layout.
+    LineLayout tmpLineLayout;
+
+    const bool isMultiline = mLayout == MULTI_LINE_BOX;
+    const GlyphIndex lastGlyphIndex = parameters.totalNumberOfGlyphs - 1u;
+
+    // If the first glyph has a negative bearing its absolute value needs to be added to the line length.
+    // In the case the line starts with a right to left character the bearing needs to be substracted to the line length.
+    const GlyphInfo& glyphInfo = *( parameters.glyphsBuffer + lineLayout.glyphIndex );
+    float initialHorizontalBearing = glyphInfo.xBearing;
+
+    lineLayout.characterIndex = *( parameters.glyphsToCharactersBuffer + lineLayout.glyphIndex );
+    const CharacterDirection firstCharacterDirection = ( NULL == parameters.characterDirectionBuffer ) ? false : *( parameters.characterDirectionBuffer + lineLayout.characterIndex );
+
+    if( RTL == firstCharacterDirection )
+    {
+      initialHorizontalBearing = -initialHorizontalBearing;
+
+      if( 0.f < glyphInfo.xBearing )
+      {
+        tmpLineLayout.length = glyphInfo.xBearing;
+        initialHorizontalBearing = 0.f;
+      }
+    }
+    else
+    {
+      if( 0.f > glyphInfo.xBearing )
+      {
+        tmpLineLayout.length = -glyphInfo.xBearing;
+        initialHorizontalBearing = 0.f;
+      }
+    }
+
+    // Calculate the line height if there is no characters.
+    FontId lastFontId = glyphInfo.fontId;
+    UpdateLineHeight( lastFontId, tmpLineLayout );
+
+    const float boundingBoxWidth = parameters.boundingBox.width - initialHorizontalBearing;
 
-    std::vector<Vector2> glyphPositions;
-    glyphPositions.reserve( glyphCount );
+    bool oneWordLaidOut = false;
 
-    if( glyphCount > 0 )
+    for( GlyphIndex glyphIndex = lineLayout.glyphIndex;
+         glyphIndex < parameters.totalNumberOfGlyphs;
+         ++glyphIndex )
     {
-      // FIXME Single font assumption
-      Text::FontMetrics fontMetrics;
-      GlyphInfo firstGlyph;
-      visualModel.GetGlyphs( &firstGlyph, 0, 1 );
-      mFontClient.GetFontMetrics( firstGlyph.fontId, fontMetrics );
+      DALI_LOG_INFO( gLogFilter, Debug::Verbose, "  glyph index : %d\n", glyphIndex );
+      const bool isLastGlyph = glyphIndex == lastGlyphIndex;
+
+      // Get the glyph info.
+      const GlyphInfo& glyphInfo = *( parameters.glyphsBuffer + glyphIndex );
+
+      // Get the character indices for the current glyph. The last character index is needed
+      // because there are glyphs formed by more than one character but their break info is
+      // given only for the last character.
+      const Length charactersPerGlyph = *( parameters.charactersPerGlyphBuffer + glyphIndex );
+      const CharacterIndex characterFirstIndex = *( parameters.glyphsToCharactersBuffer + glyphIndex );
+      const CharacterIndex characterLastIndex = characterFirstIndex + ( ( 1u > charactersPerGlyph ) ? 0u : charactersPerGlyph - 1u );
+
+      // Get the line break info for the current character.
+      const LineBreakInfo lineBreakInfo = *( parameters.lineBreakInfoBuffer + characterLastIndex );
+
+      // Get the word break info for the current character.
+      const WordBreakInfo wordBreakInfo = *( parameters.wordBreakInfoBuffer + characterLastIndex );
+
+      // Increase the number of characters.
+      tmpLineLayout.numberOfCharacters += charactersPerGlyph;
 
-      float penX( 0 );
-      float penY( fontMetrics.ascender ); // Move to baseline
+      // Increase the number of glyphs.
+      tmpLineLayout.numberOfGlyphs++;
 
-      for( unsigned int i=0; i<glyphCount; ++i )
+      // Check whether is a white space.
+      const Character character = *( parameters.textBuffer + characterFirstIndex );
+      const bool isWhiteSpace = TextAbstraction::IsWhiteSpace( character );
+
+      // Used to restore the temporal line layout when a single word does not fit in the control's width and is split by character.
+      const float previousTmpLineLength = tmpLineLayout.length;
+      const float previousTmpWidthAdvanceDiff = tmpLineLayout.widthAdvanceDiff;
+
+      // Increase the accumulated length.
+      if( isWhiteSpace )
+      {
+        // Add the length to the length of white spaces at the end of the line.
+        tmpLineLayout.wsLengthEndOfLine += glyphInfo.advance; // The advance is used as the width is always zero for the white spaces.
+      }
+      else
+      {
+        // Add as well any previous white space length.
+        tmpLineLayout.length += tmpLineLayout.wsLengthEndOfLine + glyphInfo.advance;
+        if( RTL == firstCharacterDirection )
+        {
+          tmpLineLayout.widthAdvanceDiff = -glyphInfo.xBearing;
+        }
+        else
+        {
+          tmpLineLayout.widthAdvanceDiff = glyphInfo.xBearing + glyphInfo.width - glyphInfo.advance;
+        }
+
+        // Clear the white space length at the end of the line.
+        tmpLineLayout.wsLengthEndOfLine = 0.f;
+      }
+
+      // Check if the accumulated length fits in the width of the box.
+      if( ( completelyFill || isMultiline ) && !isWhiteSpace &&
+          ( lineLayout.length + lineLayout.wsLengthEndOfLine + tmpLineLayout.length + tmpLineLayout.widthAdvanceDiff > boundingBoxWidth ) )
       {
-        GlyphInfo glyph;
-        visualModel.GetGlyphs( &glyph, i, 1 );
+        // Current word does not fit in the box's width.
+        if( !oneWordLaidOut || completelyFill )
+        {
+          DALI_LOG_INFO( gLogFilter, Debug::Verbose, "  Break the word by character\n" );
+
+          // The word's with doesn't fit in the control's with. It needs to be split by character.
+          if( tmpLineLayout.numberOfGlyphs > 0u )
+          {
+            tmpLineLayout.numberOfCharacters -= charactersPerGlyph;
+            --tmpLineLayout.numberOfGlyphs;
+            tmpLineLayout.length = previousTmpLineLength;
+            tmpLineLayout.widthAdvanceDiff = previousTmpWidthAdvanceDiff;
+          }
 
-        glyphPositions.push_back( Vector2( penX + glyph.xBearing,
-                                           penY - glyph.yBearing ) );
+          // Add part of the word to the line layout.
+          MergeLineLayout( lineLayout, tmpLineLayout );
+        }
+        else
+        {
+          DALI_LOG_INFO( gLogFilter, Debug::Verbose, "  Current word does not fit.\n" );
+        }
+        DALI_LOG_INFO( gLogFilter, Debug::Verbose, "<--GetLineLayoutForBox\n" );
+        return;
+      }
+
+      if( ( isMultiline || isLastGlyph ) &&
+          ( TextAbstraction::LINE_MUST_BREAK == lineBreakInfo ) )
+      {
+        // Must break the line. Update the line layout and return.
+        MergeLineLayout( lineLayout, tmpLineLayout );
 
-        penX += glyph.advance;
+        DALI_LOG_INFO( gLogFilter, Debug::Verbose, "  Must break\n" );
+        DALI_LOG_INFO( gLogFilter, Debug::Verbose, "<--GetLineLayoutForBox\n" );
+        return;
       }
 
-      visualModel.SetGlyphPositions( &glyphPositions[0], glyphCount );
+      if( isMultiline &&
+          ( TextAbstraction::WORD_BREAK == wordBreakInfo ) )
+      {
+        oneWordLaidOut = true;
+        DALI_LOG_INFO( gLogFilter, Debug::Verbose, "  One word laid out\n" );
+
+        // Current glyph is the last one of the current word.
+        // Add the temporal layout to the current one.
+        MergeLineLayout( lineLayout, tmpLineLayout );
+
+        tmpLineLayout.Clear();
+      }
 
-      visualModel.SetActualSize( Vector2(penX, fontMetrics.height) );
+      // Check if the font of the current glyph is the same of the previous one.
+      // If it's different the ascender and descender need to be updated.
+      if( lastFontId != glyphInfo.fontId )
+      {
+        UpdateLineHeight( glyphInfo.fontId, tmpLineLayout );
+        lastFontId = glyphInfo.fontId;
+      }
     }
+    DALI_LOG_INFO( gLogFilter, Debug::Verbose, "<--GetLineLayoutForBox\n" );
   }
 
-  // TODO - Rewrite this to handle bidi
-  void MultiLineLayout( const Vector2& boundingBox, VisualModel& visualModel )
+  void SetGlyphPositions( const GlyphInfo* const glyphsBuffer,
+                          Length numberOfGlyphs,
+                          float penY,
+                          Vector2* glyphPositionsBuffer )
   {
-    Length glyphCount = visualModel.GetNumberOfGlyphs();
+    // Traverse the glyphs and set the positions.
 
-    std::vector<Vector2> glyphPositions;
-    glyphPositions.reserve( glyphCount );
+    // Check if the x bearing of the first character is negative.
+    // If it has a negative x bearing, it will exceed the boundaries of the actor,
+    // so the penX position needs to be moved to the right.
+    float penX = 0.f;
 
-    if( glyphCount > 0 )
+    const GlyphInfo& glyph = *glyphsBuffer;
+    if( 0.f > glyph.xBearing )
     {
-      Size actualSize;
+      penX = -glyph.xBearing;
+    }
+
+    for( GlyphIndex i = 0u; i < numberOfGlyphs; ++i )
+    {
+      const GlyphInfo& glyph = *( glyphsBuffer + i );
+      Vector2& position = *( glyphPositionsBuffer + i );
 
-      // FIXME Single font assumption
-      Text::FontMetrics fontMetrics;
-      GlyphInfo firstGlyph;
-      visualModel.GetGlyphs( &firstGlyph, 0, 1 );
-      mFontClient.GetFontMetrics( firstGlyph.fontId, fontMetrics );
+      position.x = penX + glyph.xBearing;
+      position.y = penY - glyph.yBearing;
+
+      penX += glyph.advance;
+    }
+  }
 
-      float penX( 0 );
-      float penY( fontMetrics.ascender ); // Move to baseline
+  bool LayoutText( const LayoutParameters& layoutParameters,
+                   Vector<Vector2>& glyphPositions,
+                   Vector<LineRun>& lines,
+                   Size& actualSize )
+  {
+    DALI_LOG_INFO( gLogFilter, Debug::Verbose, "-->LayoutText\n" );
+    DALI_LOG_INFO( gLogFilter, Debug::Verbose, "  box size %f, %f\n", layoutParameters.boundingBox.width, layoutParameters.boundingBox.height );
 
-      unsigned int i=0;
-      while( i < glyphCount )
+    float penY = 0.f;
+    for( GlyphIndex index = 0u; index < layoutParameters.totalNumberOfGlyphs; )
+    {
+      // Get the layout for the line.
+      LineLayout layout;
+      layout.glyphIndex = index;
+      GetLineLayoutForBox( layoutParameters,
+                           layout,
+                           false );
+
+      DALI_LOG_INFO( gLogFilter, Debug::Verbose, "           glyph index %d\n", layout.glyphIndex );
+      DALI_LOG_INFO( gLogFilter, Debug::Verbose, "       character index %d\n", layout.characterIndex );
+      DALI_LOG_INFO( gLogFilter, Debug::Verbose, "      number of glyphs %d\n", layout.numberOfGlyphs );
+      DALI_LOG_INFO( gLogFilter, Debug::Verbose, "  number of characters %d\n", layout.numberOfCharacters );
+      DALI_LOG_INFO( gLogFilter, Debug::Verbose, "                length %f\n", layout.length );
+
+      if( 0u == layout.numberOfGlyphs )
       {
-        // Skip initial whitespace
-        for( ; i<glyphCount; ++i )
-        {
-          GlyphInfo glyph;
-          visualModel.GetGlyphs( &glyph, i, 1 );
+        // The width is too small and no characters are laid-out.
+        DALI_LOG_INFO( gLogFilter, Debug::Verbose, "<--LayoutText width too small!\n\n" );
+        return false;
+      }
 
-          if( glyph.width  > 0 &&
-              glyph.height > 0 )
-          {
-            break;
-          }
-          else
-          {
-            glyphPositions.push_back( Vector2( penX + glyph.xBearing,
-                                               penY - glyph.yBearing ) );
-          }
-        }
+      // Set the line position. Discard if ellipsis is enabled and the position exceeds the boundaries
+      // of the box.
+      penY += layout.ascender;
+
+      DALI_LOG_INFO( gLogFilter, Debug::Verbose, "  pen y %f\n", penY );
+      if( mEllipsisEnabled &&
+          ( ( penY - layout.descender > layoutParameters.boundingBox.height ) ||
+            ( ( mLayout == SINGLE_LINE_BOX ) &&
+              ( layout.length + layout.widthAdvanceDiff > layoutParameters.boundingBox.width ) ) ) )
+      {
+        // Do not layout more lines if ellipsis is enabled.
+
+        // The last line needs to be completely filled with characters.
+        // Part of a word may be used.
+
+        const Length numberOfLines = lines.Count();
 
-        // Find last glyph for the next line
-        unsigned int endIndex = i;
-        float endPenX = penX;
-        unsigned int j=i;
-        for( ; j<glyphCount; ++j )
+        LineRun lineRun;
+        LineLayout ellipsisLayout;
+        if( 0u != numberOfLines )
         {
-          GlyphInfo glyph;
-          visualModel.GetGlyphs( &glyph, j, 1 );
+          // Get the last line and layout it again with the 'completelyFill' flag to true.
+          lineRun = *( lines.Begin() + ( numberOfLines - 1u ) );
 
-          endPenX += glyph.advance;
+          penY -= layout.ascender - lineRun.descender;
 
-          if( glyph.width  <= 0 ||
-              glyph.height <= 0 )
-          {
-            // Potential line end found
-            endIndex = j;
-          }
-          else if( endPenX > boundingBox.width )
-          {
-            break;
-          }
+          ellipsisLayout.glyphIndex = lineRun.glyphIndex;
+        }
+        else
+        {
+          lineRun.glyphIndex = 0u;
+          ellipsisLayout.glyphIndex = 0u;
         }
 
-        actualSize.width = ( actualSize.width < endPenX ) ? endPenX : actualSize.width;
+        GetLineLayoutForBox( layoutParameters,
+                             ellipsisLayout,
+                             true );
+
+        lineRun.numberOfGlyphs = ellipsisLayout.numberOfGlyphs;
+        lineRun.characterRun.characterIndex = ellipsisLayout.characterIndex;
+        lineRun.characterRun.numberOfCharacters = ellipsisLayout.numberOfCharacters;
+        lineRun.width = layoutParameters.boundingBox.width;
+        lineRun.ascender = ellipsisLayout.ascender;
+        lineRun.descender = ellipsisLayout.descender;
+        lineRun.extraLength = ellipsisLayout.wsLengthEndOfLine > 0.f ? ellipsisLayout.wsLengthEndOfLine - ellipsisLayout.widthAdvanceDiff : 0.f;
+        lineRun.ellipsis = true;
+
+        actualSize.width = layoutParameters.boundingBox.width;
+        actualSize.height += ( lineRun.ascender + -lineRun.descender );
+
+        SetGlyphPositions( layoutParameters.glyphsBuffer + lineRun.glyphIndex,
+                           ellipsisLayout.numberOfGlyphs,
+                           penY,
+                           glyphPositions.Begin() + lineRun.glyphIndex );
 
-        // If end of text or no whitespace found
-        if( glyphCount == j ||
-            endIndex == i )
+        if( 0u != numberOfLines )
         {
-          endIndex = j;
+          // Set the last line with the ellipsis layout.
+          *( lines.Begin() + ( numberOfLines - 1u ) ) = lineRun;
+        }
+        else
+        {
+          // Push the line.
+          lines.PushBack( lineRun );
         }
 
-        for( ; i<endIndex; ++i )
+        break;
+      }
+      else
+      {
+        LineRun lineRun;
+        lineRun.glyphIndex = index;
+        lineRun.numberOfGlyphs = layout.numberOfGlyphs;
+        lineRun.characterRun.characterIndex = layout.characterIndex;
+        lineRun.characterRun.numberOfCharacters = layout.numberOfCharacters;
+        lineRun.width = layout.length + layout.widthAdvanceDiff;
+        lineRun.ascender = layout.ascender;
+        lineRun.descender = layout.descender;
+        lineRun.extraLength = layout.wsLengthEndOfLine > 0.f ? layout.wsLengthEndOfLine - layout.widthAdvanceDiff : 0.f;
+        lineRun.direction = false;
+        lineRun.ellipsis = false;
+
+        lines.PushBack( lineRun );
+
+        // Update the actual size.
+        if( lineRun.width > actualSize.width )
         {
-          GlyphInfo glyph;
-          visualModel.GetGlyphs( &glyph, i, 1 );
+          actualSize.width = lineRun.width;
+        }
+
+        actualSize.height += ( lineRun.ascender + -lineRun.descender );
+
+        SetGlyphPositions( layoutParameters.glyphsBuffer + index,
+                           layout.numberOfGlyphs,
+                           penY,
+                           glyphPositions.Begin() + index );
+
+        penY += -layout.descender;
+
+        // Increase the glyph index.
+        index += layout.numberOfGlyphs;
+      }
+    }
 
-          glyphPositions.push_back( Vector2( penX + glyph.xBearing,
-                                             penY - glyph.yBearing ) );
+    DALI_LOG_INFO( gLogFilter, Debug::Verbose, "<--LayoutText\n\n" );
 
+    return true;
+  }
+
+  void ReLayoutRightToLeftLines( const LayoutParameters& layoutParameters,
+                                 Vector<Vector2>& glyphPositions )
+  {
+    // Traverses the paragraphs with right to left characters.
+    for( LineIndex lineIndex = 0u; lineIndex < layoutParameters.numberOfBidirectionalInfoRuns; ++lineIndex )
+    {
+      const BidirectionalLineInfoRun& bidiLine = *( layoutParameters.lineBidirectionalInfoRunsBuffer + lineIndex );
+
+      float penX = 0.f;
+
+      const CharacterIndex characterVisualIndex = bidiLine.characterRun.characterIndex + *bidiLine.visualToLogicalMap;
+      const GlyphInfo& glyph = *( layoutParameters.glyphsBuffer + *( layoutParameters.charactersToGlyphsBuffer + characterVisualIndex ) );
+
+      penX = -glyph.xBearing;
+
+      Vector2* glyphPositionsBuffer = glyphPositions.Begin();
+
+      // Traverses the characters of the right to left paragraph.
+      for( CharacterIndex characterLogicalIndex = 0u;
+           characterLogicalIndex < bidiLine.characterRun.numberOfCharacters;
+           ++characterLogicalIndex )
+      {
+        // Convert the character in the logical order into the character in the visual order.
+        const CharacterIndex characterVisualIndex = bidiLine.characterRun.characterIndex + *( bidiLine.visualToLogicalMap + characterLogicalIndex );
+
+        // Get the number of glyphs of the character.
+        const Length numberOfGlyphs = *( layoutParameters.glyphsPerCharacterBuffer + characterVisualIndex );
+
+        for( GlyphIndex index = 0u; index < numberOfGlyphs; ++index )
+        {
+          // Convert the character in the visual order into the glyph in the visual order.
+          const GlyphIndex glyphIndex = *( layoutParameters.charactersToGlyphsBuffer + characterVisualIndex ) + index;
+
+          DALI_ASSERT_DEBUG( 0u <= glyphIndex && glyphIndex < layoutParameters.totalNumberOfGlyphs );
+
+          const GlyphInfo& glyph = *( layoutParameters.glyphsBuffer + glyphIndex );
+          Vector2& position = *( glyphPositionsBuffer + glyphIndex );
+
+          position.x = penX + glyph.xBearing;
           penX += glyph.advance;
         }
+      }
+    }
+  }
 
-        // Go to next line
-        penX = 0;
-        penY += fontMetrics.height;
+  void Align( const Size& layoutSize,
+              Vector<LineRun>& lines )
+  {
+    // Traverse all lines and align the glyphs.
 
-        actualSize.height += fontMetrics.height;
+    for( Vector<LineRun>::Iterator it = lines.Begin(), endIt = lines.End();
+         it != endIt;
+         ++it )
+    {
+      LineRun& line = *it;
+      const bool isLastLine = lines.End() == it + 1u;
+
+      // Calculate the alignment offset accordingly with the align option,
+      // the box width, line length, and the paragraphs direction.
+      CalculateHorizontalAlignment( layoutSize.width,
+                                    line,
+                                    isLastLine );
+    }
+  }
+
+  void CalculateHorizontalAlignment( float boxWidth,
+                                     LineRun& line,
+                                     bool isLastLine )
+  {
+    line.alignmentOffset = 0.f;
+    const bool isRTL = RTL == line.direction;
+    float lineLength = line.width;
+
+    HorizontalAlignment alignment = mHorizontalAlignment;
+    if( isRTL &&
+        ( HORIZONTAL_ALIGN_CENTER != alignment ) )
+    {
+      if( HORIZONTAL_ALIGN_BEGIN == alignment )
+      {
+        alignment = HORIZONTAL_ALIGN_END;
       }
+      else
+      {
+        alignment = HORIZONTAL_ALIGN_BEGIN;
+      }
+    }
 
-      visualModel.SetGlyphPositions( &glyphPositions[0], glyphCount );
+    switch( alignment )
+    {
+      case HORIZONTAL_ALIGN_BEGIN:
+      {
+        line.alignmentOffset = 0.f;
+        break;
+      }
+      case HORIZONTAL_ALIGN_CENTER:
+      {
+        line.alignmentOffset = floorf( 0.5f * ( boxWidth - lineLength ) ); // try to avoid pixel alignment.
+        break;
+      }
+      case HORIZONTAL_ALIGN_END:
+      {
+        line.alignmentOffset = boxWidth - lineLength;
+        break;
+      }
+    }
 
-      visualModel.SetActualSize( actualSize );
+    if( isRTL )
+    {
+      line.alignmentOffset -= line.extraLength;
     }
   }
 
-  unsigned int mLayout;
+  LayoutEngine::Layout mLayout;
+  LayoutEngine::HorizontalAlignment mHorizontalAlignment;
+  LayoutEngine::VerticalAlignment mVerticalAlignment;
 
   TextAbstraction::FontClient mFontClient;
+
+  bool mEllipsisEnabled:1;
 };
 
 LayoutEngine::LayoutEngine()
@@ -231,17 +654,59 @@ unsigned int LayoutEngine::GetLayout() const
   return mImpl->mLayout;
 }
 
-void LayoutEngine::UpdateVisualModel( const Vector2& boundingBox,
-                                      const Vector<GlyphInfo>& glyphs,
-                                      const Vector<CharacterIndex>& characterIndices,
-                                      const Vector<Length>& charactersPerGlyph,
-                                      VisualModel& visualModel )
-{
-  mImpl->UpdateVisualModel( boundingBox,
-                            glyphs,
-                            characterIndices,
-                            charactersPerGlyph,
-                            visualModel );
+void LayoutEngine::SetTextEllipsisEnabled( bool enabled )
+{
+  mImpl->mEllipsisEnabled = enabled;
+}
+
+bool LayoutEngine::GetTextEllipsisEnabled() const
+{
+  return mImpl->mEllipsisEnabled;
+}
+
+void LayoutEngine::SetHorizontalAlignment( HorizontalAlignment alignment )
+{
+  mImpl->mHorizontalAlignment = alignment;
+}
+
+LayoutEngine::HorizontalAlignment LayoutEngine::GetHorizontalAlignment() const
+{
+  return mImpl->mHorizontalAlignment;
+}
+
+void LayoutEngine::SetVerticalAlignment( VerticalAlignment alignment )
+{
+  mImpl->mVerticalAlignment = alignment;
+}
+
+LayoutEngine::VerticalAlignment LayoutEngine::GetVerticalAlignment() const
+{
+  return mImpl->mVerticalAlignment;
+}
+
+bool LayoutEngine::LayoutText( const LayoutParameters& layoutParameters,
+                               Vector<Vector2>& glyphPositions,
+                               Vector<LineRun>& lines,
+                               Size& actualSize )
+{
+  return mImpl->LayoutText( layoutParameters,
+                            glyphPositions,
+                            lines,
+                            actualSize );
+}
+
+void LayoutEngine::ReLayoutRightToLeftLines( const LayoutParameters& layoutParameters,
+                                             Vector<Vector2>& glyphPositions )
+{
+  mImpl->ReLayoutRightToLeftLines( layoutParameters,
+                                   glyphPositions );
+}
+
+void LayoutEngine::Align( const Size& layoutSize,
+                          Vector<LineRun>& lines )
+{
+  mImpl->Align( layoutSize,
+                lines );
 }
 
 } // namespace Text