1/* 2 * Copyright (C) Research In Motion Limited 2010-2012. All rights reserved. 3 * 4 * This library is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU Library General Public 6 * License as published by the Free Software Foundation; either 7 * version 2 of the License, or (at your option) any later version. 8 * 9 * This library is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 * Library General Public License for more details. 13 * 14 * You should have received a copy of the GNU Library General Public License 15 * along with this library; see the file COPYING.LIB. If not, write to 16 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 17 * Boston, MA 02110-1301, USA. 18 */ 19 20#ifndef SVGTextLayoutEngine_h 21#define SVGTextLayoutEngine_h 22 23#if ENABLE(SVG) 24#include "Path.h" 25#include "SVGTextChunkBuilder.h" 26#include "SVGTextFragment.h" 27#include "SVGTextLayoutAttributes.h" 28#include "SVGTextMetrics.h" 29#include <wtf/Vector.h> 30 31namespace WebCore { 32 33class RenderObject; 34class RenderStyle; 35class RenderSVGInlineText; 36class SVGElement; 37class SVGInlineTextBox; 38class SVGRenderStyle; 39 40// SVGTextLayoutEngine performs the second layout phase for SVG text. 41// 42// The InlineBox tree was created, containing the text chunk information, necessary to apply 43// certain SVG specific text layout properties (text-length adjustments and text-anchor). 44// The second layout phase uses the SVGTextLayoutAttributes stored in the individual 45// RenderSVGInlineText renderers to compute the final positions for each character 46// which are stored in the SVGInlineTextBox objects. 47 48class SVGTextLayoutEngine { 49 WTF_MAKE_NONCOPYABLE(SVGTextLayoutEngine); 50public: 51 SVGTextLayoutEngine(Vector<SVGTextLayoutAttributes*>&); 52 53 Vector<SVGTextLayoutAttributes*>& layoutAttributes() { return m_layoutAttributes; } 54 SVGTextChunkBuilder& chunkLayoutBuilder() { return m_chunkLayoutBuilder; } 55 56 void beginTextPathLayout(RenderObject*, SVGTextLayoutEngine& lineLayout); 57 void endTextPathLayout(); 58 59 void layoutInlineTextBox(SVGInlineTextBox*); 60 void finishLayout(); 61 62private: 63 void updateCharacerPositionIfNeeded(float& x, float& y); 64 void updateCurrentTextPosition(float x, float y, float glyphAdvance); 65 void updateRelativePositionAdjustmentsIfNeeded(float dx, float dy); 66 67 void recordTextFragment(SVGInlineTextBox*, Vector<SVGTextMetrics>&); 68 bool parentDefinesTextLength(RenderObject*) const; 69 70 void layoutTextOnLineOrPath(SVGInlineTextBox*, RenderSVGInlineText*, const RenderStyle*); 71 void finalizeTransformMatrices(Vector<SVGInlineTextBox*>&); 72 73 bool currentLogicalCharacterAttributes(SVGTextLayoutAttributes*&); 74 bool currentLogicalCharacterMetrics(SVGTextLayoutAttributes*&, SVGTextMetrics&); 75 bool currentVisualCharacterMetrics(SVGInlineTextBox*, Vector<SVGTextMetrics>&, SVGTextMetrics&); 76 77 void advanceToNextLogicalCharacter(const SVGTextMetrics&); 78 void advanceToNextVisualCharacter(const SVGTextMetrics&); 79 80private: 81 Vector<SVGTextLayoutAttributes*>& m_layoutAttributes; 82 83 Vector<SVGInlineTextBox*> m_lineLayoutBoxes; 84 Vector<SVGInlineTextBox*> m_pathLayoutBoxes; 85 SVGTextChunkBuilder m_chunkLayoutBuilder; 86 87 SVGTextFragment m_currentTextFragment; 88 unsigned m_layoutAttributesPosition; 89 unsigned m_logicalCharacterOffset; 90 unsigned m_logicalMetricsListOffset; 91 unsigned m_visualCharacterOffset; 92 unsigned m_visualMetricsListOffset; 93 float m_x; 94 float m_y; 95 float m_dx; 96 float m_dy; 97 bool m_isVerticalText; 98 bool m_inPathLayout; 99 100 // Text on path layout 101 Path m_textPath; 102 float m_textPathLength; 103 float m_textPathStartOffset; 104 float m_textPathCurrentOffset; 105 float m_textPathSpacing; 106 float m_textPathScaling; 107}; 108 109} // namespace WebCore 110 111#endif // ENABLE(SVG) 112#endif 113