2 * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
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
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11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
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21 #ifndef RenderOverflow_h
22 #define RenderOverflow_h
24 #include "platform/geometry/LayoutRect.h"
28 // RenderOverflow is a class for tracking content that spills out of a box. This class is used by RenderBox and
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).
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.
37 // Examples of visual overflow are shadows, text stroke (and eventually outline and border-image).
39 // This object is allocated only when some of these fields have non-default values in the owning box.
40 class RenderOverflow {
41 WTF_MAKE_NONCOPYABLE(RenderOverflow); WTF_MAKE_FAST_ALLOCATED;
43 RenderOverflow(const LayoutRect& layoutRect, const LayoutRect& visualRect)
44 : m_layoutOverflow(layoutRect)
45 , m_visualOverflow(visualRect)
49 const LayoutRect layoutOverflowRect() const { return m_layoutOverflow; }
50 const LayoutRect visualOverflowRect() const { return m_visualOverflow; }
51 LayoutRect contentsVisualOverflowRect() const { return m_contentsVisualOverflow; }
53 void move(LayoutUnit dx, LayoutUnit dy);
55 void addLayoutOverflow(const LayoutRect&);
56 void addVisualOverflow(const LayoutRect&);
57 void addContentsVisualOverflow(const LayoutRect& rect) { m_contentsVisualOverflow.unite(rect); }
59 void setLayoutOverflow(const LayoutRect&);
60 void setVisualOverflow(const LayoutRect&);
62 LayoutUnit layoutClientAfterEdge() const { return m_layoutClientAfterEdge; }
63 void setLayoutClientAfterEdge(LayoutUnit clientAfterEdge) { m_layoutClientAfterEdge = clientAfterEdge; }
66 LayoutRect m_layoutOverflow;
67 LayoutRect m_visualOverflow;
68 LayoutRect m_contentsVisualOverflow;
70 LayoutUnit m_layoutClientAfterEdge;
73 inline void RenderOverflow::move(LayoutUnit dx, LayoutUnit dy)
75 m_layoutOverflow.move(dx, dy);
76 m_visualOverflow.move(dx, dy);
77 m_contentsVisualOverflow.move(dx, dy);
80 inline void RenderOverflow::addLayoutOverflow(const LayoutRect& rect)
82 LayoutUnit maxX = std::max(rect.maxX(), m_layoutOverflow.maxX());
83 LayoutUnit maxY = std::max(rect.maxY(), m_layoutOverflow.maxY());
84 LayoutUnit minX = std::min(rect.x(), m_layoutOverflow.x());
85 LayoutUnit minY = std::min(rect.y(), m_layoutOverflow.y());
86 // In case the width/height is larger than LayoutUnit can represent, fix the right/bottom edge and shift the top/left ones
87 m_layoutOverflow.setWidth(maxX - minX);
88 m_layoutOverflow.setHeight(maxY - minY);
89 m_layoutOverflow.setX(maxX - m_layoutOverflow.width());
90 m_layoutOverflow.setY(maxY - m_layoutOverflow.height());
93 inline void RenderOverflow::addVisualOverflow(const LayoutRect& rect)
95 LayoutUnit maxX = std::max(rect.maxX(), m_visualOverflow.maxX());
96 LayoutUnit maxY = std::max(rect.maxY(), m_visualOverflow.maxY());
97 m_visualOverflow.setX(std::min(rect.x(), m_visualOverflow.x()));
98 m_visualOverflow.setY(std::min(rect.y(), m_visualOverflow.y()));
99 m_visualOverflow.setWidth(maxX - m_visualOverflow.x());
100 m_visualOverflow.setHeight(maxY - m_visualOverflow.y());
103 inline void RenderOverflow::setLayoutOverflow(const LayoutRect& rect)
105 m_layoutOverflow = rect;
108 inline void RenderOverflow::setVisualOverflow(const LayoutRect& rect)
110 m_visualOverflow = rect;
113 } // namespace WebCore
115 #endif // RenderOverflow_h