1 /* 2 * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. 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 21 #ifndef RenderOverflow_h 22 #define RenderOverflow_h 23 24 #include "IntRect.h" 25 26 namespace WebCore 27 { 28 // RenderOverflow is a class for tracking content that spills out of a box. This class is used by RenderBox and 29 // InlineFlowBox. 30 // 31 // There are two types of overflow: layout overflow (which is expected to be reachable via scrolling mechanisms) and 32 // visual overflow (which is not expected to be reachable via scrolling mechanisms). 33 // 34 // Layout overflow examples include other boxes that spill out of our box, For example, in the inline case a tall image 35 // could spill out of a line box. 36 37 // Examples of visual overflow are shadows, text stroke (and eventually outline and border-image). 38 39 // This object is allocated only when some of these fields have non-default values in the owning box. 40 class RenderOverflow : public Noncopyable { 41 public: 42 RenderOverflow(const IntRect& defaultRect = IntRect()) 43 : m_topLayoutOverflow(defaultRect.y()) 44 , m_bottomLayoutOverflow(defaultRect.bottom()) 45 , m_leftLayoutOverflow(defaultRect.x()) 46 , m_rightLayoutOverflow(defaultRect.right()) 47 , m_topVisualOverflow(defaultRect.y()) 48 , m_bottomVisualOverflow(defaultRect.bottom()) 49 , m_leftVisualOverflow(defaultRect.x()) 50 , m_rightVisualOverflow(defaultRect.right()) 51 { 52 } 53 54 int topLayoutOverflow() const { return m_topLayoutOverflow; } 55 int bottomLayoutOverflow() const { return m_bottomLayoutOverflow; } 56 int leftLayoutOverflow() const { return m_leftLayoutOverflow; } 57 int rightLayoutOverflow() const { return m_rightLayoutOverflow; } 58 IntRect layoutOverflowRect() const; 59 60 int topVisualOverflow() const { return m_topVisualOverflow; } 61 int bottomVisualOverflow() const { return m_bottomVisualOverflow; } 62 int leftVisualOverflow() const { return m_leftVisualOverflow; } 63 int rightVisualOverflow() const { return m_rightVisualOverflow; } 64 IntRect visualOverflowRect() const; 65 66 IntRect visibleOverflowRect() const; 67 68 void setTopLayoutOverflow(int overflow) { m_topLayoutOverflow = overflow; } 69 void setBottomLayoutOverflow(int overflow) { m_bottomLayoutOverflow = overflow; } 70 void setLeftLayoutOverflow(int overflow) { m_leftLayoutOverflow = overflow; } 71 void setRightLayoutOverflow(int overflow) { m_rightLayoutOverflow = overflow; } 72 73 void setTopVisualOverflow(int overflow) { m_topVisualOverflow = overflow; } 74 void setBottomVisualOverflow(int overflow) { m_bottomVisualOverflow = overflow; } 75 void setLeftVisualOverflow(int overflow) { m_leftVisualOverflow = overflow; } 76 void setRightVisualOverflow(int overflow) { m_rightVisualOverflow = overflow; } 77 78 void move(int dx, int dy); 79 80 void addLayoutOverflow(const IntRect&); 81 void addVisualOverflow(const IntRect&); 82 83 void resetLayoutOverflow(const IntRect& defaultRect); 84 85 private: 86 int m_topLayoutOverflow; 87 int m_bottomLayoutOverflow; 88 int m_leftLayoutOverflow; 89 int m_rightLayoutOverflow; 90 91 int m_topVisualOverflow; 92 int m_bottomVisualOverflow; 93 int m_leftVisualOverflow; 94 int m_rightVisualOverflow; 95 }; 96 97 inline IntRect RenderOverflow::layoutOverflowRect() const 98 { 99 return IntRect(m_leftLayoutOverflow, m_topLayoutOverflow, m_rightLayoutOverflow - m_leftLayoutOverflow, m_bottomLayoutOverflow - m_topLayoutOverflow); 100 } 101 102 inline IntRect RenderOverflow::visualOverflowRect() const 103 { 104 return IntRect(m_leftVisualOverflow, m_topVisualOverflow, m_rightVisualOverflow - m_leftVisualOverflow, m_bottomVisualOverflow - m_topVisualOverflow); 105 } 106 107 inline IntRect RenderOverflow::visibleOverflowRect() const 108 { 109 IntRect combinedRect(layoutOverflowRect()); 110 combinedRect.unite(visualOverflowRect()); 111 return combinedRect; 112 } 113 114 inline void RenderOverflow::move(int dx, int dy) 115 { 116 m_topLayoutOverflow += dy; 117 m_bottomLayoutOverflow += dy; 118 m_leftLayoutOverflow += dx; 119 m_rightLayoutOverflow += dx; 120 121 m_topVisualOverflow += dy; 122 m_bottomVisualOverflow += dy; 123 m_leftVisualOverflow += dx; 124 m_rightVisualOverflow += dx; 125 } 126 127 inline void RenderOverflow::addLayoutOverflow(const IntRect& rect) 128 { 129 m_topLayoutOverflow = std::min(rect.y(), m_topLayoutOverflow); 130 m_bottomLayoutOverflow = std::max(rect.bottom(), m_bottomLayoutOverflow); 131 m_leftLayoutOverflow = std::min(rect.x(), m_leftLayoutOverflow); 132 m_rightLayoutOverflow = std::max(rect.right(), m_rightLayoutOverflow); 133 } 134 135 inline void RenderOverflow::addVisualOverflow(const IntRect& rect) 136 { 137 m_topVisualOverflow = std::min(rect.y(), m_topVisualOverflow); 138 m_bottomVisualOverflow = std::max(rect.bottom(), m_bottomVisualOverflow); 139 m_leftVisualOverflow = std::min(rect.x(), m_leftVisualOverflow); 140 m_rightVisualOverflow = std::max(rect.right(), m_rightVisualOverflow); 141 } 142 143 inline void RenderOverflow::resetLayoutOverflow(const IntRect& rect) 144 { 145 m_topLayoutOverflow = rect.y(); 146 m_bottomLayoutOverflow = rect.bottom(); 147 m_leftLayoutOverflow = rect.x(); 148 m_rightLayoutOverflow = rect.right(); 149 } 150 151 } // namespace WebCore 152 153 #endif // RenderOverflow_h 154
