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#include "Path.h" 24#include "SVGTextChunkBuilder.h" 25#include "SVGTextFragment.h" 26#include "SVGTextLayoutAttributes.h" 27 28namespace WebCore { 29 30class RenderObject; 31class RenderStyle; 32class RenderSVGInlineText; 33class SVGElement; 34class SVGInlineTextBox; 35class SVGRenderStyle; 36 37// SVGTextLayoutEngine performs the second layout phase for SVG text. 38// 39// The InlineBox tree was created, containing the text chunk information, necessary to apply 40// certain SVG specific text layout properties (text-length adjustments and text-anchor). 41// The second layout phase uses the SVGTextLayoutAttributes stored in the individual 42// RenderSVGInlineText renderers to compute the final positions for each character 43// which are stored in the SVGInlineTextBox objects. 44 45class SVGTextLayoutEngine { 46 WTF_MAKE_NONCOPYABLE(SVGTextLayoutEngine); 47public: 48 SVGTextLayoutEngine(Vector<SVGTextLayoutAttributes*>&); 49 50 Vector<SVGTextLayoutAttributes*>& layoutAttributes() { return m_layoutAttributes; } 51 SVGTextChunkBuilder& chunkLayoutBuilder() { return m_chunkLayoutBuilder; } 52 53 void beginTextPathLayout(RenderObject*, SVGTextLayoutEngine& lineLayout); 54 void endTextPathLayout(); 55 56 void layoutInlineTextBox(SVGInlineTextBox*); 57 void finishLayout(); 58 59private: 60 void updateCharacerPositionIfNeeded(float& x, float& y); 61 void updateCurrentTextPosition(float x, float y, float glyphAdvance); 62 void updateRelativePositionAdjustmentsIfNeeded(float dx, float dy); 63 64 void recordTextFragment(SVGInlineTextBox*, Vector<SVGTextMetrics>&); 65 bool parentDefinesTextLength(RenderObject*) const; 66 67 void layoutTextOnLineOrPath(SVGInlineTextBox*, RenderSVGInlineText*, const RenderStyle*); 68 void finalizeTransformMatrices(Vector<SVGInlineTextBox*>&); 69 70 bool currentLogicalCharacterAttributes(SVGTextLayoutAttributes*&); 71 bool currentLogicalCharacterMetrics(SVGTextLayoutAttributes*&, SVGTextMetrics&); 72 bool currentVisualCharacterMetrics(SVGInlineTextBox*, Vector<SVGTextMetrics>&, SVGTextMetrics&); 73 74 void advanceToNextLogicalCharacter(const SVGTextMetrics&); 75 void advanceToNextVisualCharacter(const SVGTextMetrics&); 76 77private: 78 Vector<SVGTextLayoutAttributes*>& m_layoutAttributes; 79 80 Vector<SVGInlineTextBox*> m_lineLayoutBoxes; 81 Vector<SVGInlineTextBox*> m_pathLayoutBoxes; 82 SVGTextChunkBuilder m_chunkLayoutBuilder; 83 84 SVGTextFragment m_currentTextFragment; 85 unsigned m_layoutAttributesPosition; 86 unsigned m_logicalCharacterOffset; 87 unsigned m_logicalMetricsListOffset; 88 unsigned m_visualCharacterOffset; 89 unsigned m_visualMetricsListOffset; 90 float m_x; 91 float m_y; 92 float m_dx; 93 float m_dy; 94 bool m_isVerticalText; 95 bool m_inPathLayout; 96 97 // Text on path layout 98 Path m_textPath; 99 float m_textPathLength; 100 float m_textPathStartOffset; 101 float m_textPathCurrentOffset; 102 float m_textPathSpacing; 103 float m_textPathScaling; 104}; 105 106} // namespace WebCore 107 108#endif 109