Perform SVG text chunk processing on-the-fly

Source/core/layout/svg/SVGTextLayoutEngine.cpp

 /*
  * Copyright (C) Research In Motion Limited 2010-2012. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 159 matching lines @@
 
     Path path = textPath->layoutPath();
     if (path.isEmpty())
         return;
     m_textPathCalculator = new Path::PositionCalculator(path);
     m_textPathStartOffset = textPath->startOffset();
     m_textPathLength = path.length();
     if (m_textPathStartOffset > 0 && m_textPathStartOffset <= 1)
         m_textPathStartOffset *= m_textPathLength;
 
-    float totalLength = 0;
-    unsigned totalCharacters = 0;
+    SVGTextPathChunkBuilder textPathChunkLayoutBuilder;
+    textPathChunkLayoutBuilder.processTextChunks(lineLayout.m_lineLayoutBoxes);
 
-    SVGTextChunkBuilder textPathChunkLayoutBuilder;
-    textPathChunkLayoutBuilder.buildTextChunks(lineLayout.m_lineLayoutBoxes);
-    const Vector<SVGTextChunk>& textChunks = textPathChunkLayoutBuilder.textChunks();
-
-    unsigned size = textChunks.size();
-    for (unsigned i = 0; i < size; ++i) {
-        const SVGTextChunk& chunk = textChunks.at(i);
-
-        float length = 0;
-        unsigned characters = 0;
-        chunk.calculateLength(length, characters);
-
-        // Handle text-anchor as additional start offset for text paths.
-        m_textPathStartOffset += chunk.calculateTextAnchorShift(length);
-
-        totalLength += length;
-        totalCharacters += characters;
-    }
-
+    m_textPathStartOffset += textPathChunkLayoutBuilder.totalTextAnchorShift();
     m_textPathCurrentOffset = m_textPathStartOffset;
 
     // Eventually handle textLength adjustments.
     SVGLengthAdjustType lengthAdjust = SVGLengthAdjustUnknown;
     float desiredTextLength = 0;
 
     if (SVGTextContentElement* textContentElement = SVGTextContentElement::elementFromLayoutObject(textPath)) {
         SVGLengthContext lengthContext(textContentElement);
         lengthAdjust = textContentElement->lengthAdjust()->currentValue()->enumValue();
         if (textContentElement->textLengthIsSpecifiedByUser())
             desiredTextLength = textContentElement->textLength()->currentValue()->value(lengthContext);
         else
             desiredTextLength = 0;
     }
 
     if (!desiredTextLength)
         return;
 
+    float totalLength = textPathChunkLayoutBuilder.totalLength();
     if (lengthAdjust == SVGLengthAdjustSpacing)
-        m_textPathSpacing = (desiredTextLength - totalLength) / totalCharacters;
+        m_textPathSpacing = (desiredTextLength - totalLength) / textPathChunkLayoutBuilder.totalCharacters();
     else
         m_textPathScaling = desiredTextLength / totalLength;
 }
 
 void SVGTextLayoutEngine::endTextPathLayout()
 {
     m_inPathLayout = false;
     delete m_textPathCalculator;
     m_textPathCalculator = 0;
     m_textPathLength = 0;
@@ skipping 24 matching lines @@
     }
 
     m_lineLayoutBoxes.append(textBox);
 }
 
 void SVGTextLayoutEngine::finishLayout()
 {
     // After all text fragments are stored in their correpsonding SVGInlineTextBoxes, we can layout individual text chunks.
     // Chunk layouting is only performed for line layout boxes, not for path layout, where it has already been done.
     SVGTextChunkBuilder chunkLayoutBuilder;
-    chunkLayoutBuilder.layoutTextChunks(m_lineLayoutBoxes);
+    chunkLayoutBuilder.processTextChunks(m_lineLayoutBoxes);
 
     // Finalize transform matrices, after the chunk layout corrections have been applied, and all fragment x/y positions are finalized.
     if (!m_lineLayoutBoxes.isEmpty()) {
         chunkLayoutBuilder.finalizeTransformMatrices(m_lineLayoutBoxes);
         m_lineLayoutBoxes.clear();
     }
 
     if (!m_pathLayoutBoxes.isEmpty()) {
         chunkLayoutBuilder.finalizeTransformMatrices(m_pathLayoutBoxes);
         m_pathLayoutBoxes.clear();
@@ skipping 300 matching lines @@
     }
 
     if (!didStartTextFragment)
         return;
 
     // Close last open fragment, if needed.
     recordTextFragment(textBox, visualMetricsValues);
 }
 
 }