Save the previous character's extra width

[platform/core/uifw/dali-toolkit.git] / dali-toolkit / internal / text / layouts / layout-engine.cpp

diff --git a/dali-toolkit/internal/text/layouts/layout-engine.cpp b/dali-toolkit/internal/text/layouts/layout-engine.cpp
index ccd42ae..af257ff 100644 (file)
--- a/dali-toolkit/internal/text/layouts/layout-engine.cpp
+++ b/dali-toolkit/internal/text/layouts/layout-engine.cpp
@@ -70,7 +70,8 @@ struct LineLayout
     extraWidth( 0.f ),
     wsLengthEndOfLine( 0.f ),
     ascender( 0.f ),
-    descender( MAX_FLOAT )
+    descender( MAX_FLOAT ),
+    lineSpacing( 0.f )
   {}
 
   ~LineLayout()
@@ -100,6 +101,7 @@ struct LineLayout
   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.
+  float          lineSpacing;        ///< The line spacing
 };
 
 struct Engine::Impl
@@ -107,7 +109,8 @@ struct Engine::Impl
   Impl()
   : mLayout( Layout::Engine::SINGLE_LINE_BOX ),
     mCursorWidth( CURSOR_WIDTH ),
-    mDefaultLineSpacing( LINE_SPACING )
+    mDefaultLineSpacing( LINE_SPACING ),
+    mPreviousCharacterExtraWidth( 0.0f )
   {
   }
 
@@ -133,6 +136,9 @@ struct Engine::Impl
     {
       lineLayout.descender = fontMetrics.descender;
     }
+
+    // set the line spacing
+    lineLayout.lineSpacing = mDefaultLineSpacing;
   }
 
   /**
@@ -340,6 +346,7 @@ struct Engine::Impl
 
             const float extraWidth = glyphMetrics.xBearing + glyphMetrics.width - glyphMetrics.advance;
             tmpExtraWidth = ( 0.f < extraWidth ) ? extraWidth : 0.f;
+            tmpExtraWidth = std::max( mPreviousCharacterExtraWidth - glyphMetrics.advance, tmpExtraWidth );
           }
         }
         else
@@ -353,6 +360,7 @@ struct Engine::Impl
 
               const float extraWidth = glyphMetrics.xBearing + glyphMetrics.width - glyphMetrics.advance;
               tmpExtraWidth = ( 0.f < extraWidth ) ? extraWidth : 0.f;
+              tmpExtraWidth = std::max( mPreviousCharacterExtraWidth - glyphMetrics.advance, tmpExtraWidth );
             }
             else // LTR
             {
@@ -380,6 +388,7 @@ struct Engine::Impl
 
               const float extraWidth = glyphMetrics.xBearing + glyphMetrics.width - glyphMetrics.advance;
               tmpExtraWidth = ( 0.f < extraWidth ) ? extraWidth : 0.f;
+              tmpExtraWidth = std::max( mPreviousCharacterExtraWidth - glyphMetrics.advance, tmpExtraWidth );
             }
           }
         }
@@ -388,6 +397,9 @@ struct Engine::Impl
         tmpLineLayout.wsLengthEndOfLine = 0.f;
       }
 
+      // Save the current extra width to compare with the next one
+      mPreviousCharacterExtraWidth = tmpExtraWidth;
+
       // Check if the accumulated length fits in the width of the box.
       if( ( completelyFill || isMultiline ) && !isWhiteSpace &&
           ( tmpExtraBearing + lineLayout.length + lineLayout.wsLengthEndOfLine + tmpLineLayout.length + tmpExtraWidth > parameters.boundingBox.width ) )
@@ -568,7 +580,7 @@ struct Engine::Impl
         // Get the last line and layout it again with the 'completelyFill' flag to true.
         lineRun = linesBuffer + ( numberOfLines - 1u );
 
-        penY -= layout.ascender - lineRun->descender;
+        penY -= layout.ascender - lineRun->descender + lineRun->lineSpacing;
 
         ellipsisLayout.glyphIndex = lineRun->glyphRun.glyphIndex;
       }
@@ -601,7 +613,7 @@ struct Engine::Impl
       layoutSize.width = layoutParameters.boundingBox.width;
       if( layoutSize.height < Math::MACHINE_EPSILON_1000 )
       {
-        layoutSize.height += ( lineRun->ascender + -lineRun->descender );
+        layoutSize.height += ( lineRun->ascender + -lineRun->descender ) + lineRun->lineSpacing;
       }
 
       SetGlyphPositions( layoutParameters.glyphsBuffer + lineRun->glyphRun.glyphIndex,
@@ -639,6 +651,8 @@ struct Engine::Impl
     lineRun.glyphRun.numberOfGlyphs = layout.numberOfGlyphs;
     lineRun.characterRun.characterIndex = layout.characterIndex;
     lineRun.characterRun.numberOfCharacters = layout.numberOfCharacters;
+    lineRun.lineSpacing = mDefaultLineSpacing;
+
     if( isLastLine && !layoutParameters.isLastNewParagraph )
     {
       const float width = layout.extraBearing + layout.length + layout.extraWidth + layout.wsLengthEndOfLine;
@@ -669,7 +683,7 @@ struct Engine::Impl
       layoutSize.width = lineRun.width;
     }
 
-    layoutSize.height += ( lineRun.ascender + -lineRun.descender );
+    layoutSize.height += ( lineRun.ascender + -lineRun.descender ) + lineRun.lineSpacing;
   }
 
   /**
@@ -709,8 +723,9 @@ struct Engine::Impl
     lineRun.alignmentOffset = 0.f;
     lineRun.direction = !RTL;
     lineRun.ellipsis = false;
+    lineRun.lineSpacing = mDefaultLineSpacing;
 
-    layoutSize.height += ( lineRun.ascender + -lineRun.descender );
+    layoutSize.height += ( lineRun.ascender + -lineRun.descender ) + lineRun.lineSpacing;
   }
 
   /**
@@ -734,7 +749,7 @@ struct Engine::Impl
         layoutSize.width = line.width;
       }
 
-      layoutSize.height += ( line.ascender + -line.descender );
+      layoutSize.height += ( line.ascender + -line.descender ) + line.lineSpacing;
     }
   }
 
@@ -970,7 +985,7 @@ struct Engine::Impl
                            glyphPositionsBuffer + index - layoutParameters.startGlyphIndex );
 
         // Updates the vertical pen's position.
-        penY += -layout.descender;
+        penY += -layout.descender + layout.lineSpacing + mDefaultLineSpacing;
 
         // Increase the glyph index.
         index = nextIndex;
@@ -1203,11 +1218,13 @@ struct Engine::Impl
     line.alignmentOffset = 0.f;
     line.direction = !RTL;
     line.ellipsis = false;
+    line.lineSpacing = mDefaultLineSpacing;
   }
 
   Type mLayout;
   float mCursorWidth;
   float mDefaultLineSpacing;
+  float mPreviousCharacterExtraWidth;
 
   IntrusivePtr<Metrics> mMetrics;
 };