1 | /* |
2 | * Copyright (C) 2012 Apple Inc. All rights reserved. |
3 | * |
4 | * Redistribution and use in source and binary forms, with or without |
5 | * modification, are permitted provided that the following conditions |
6 | * are met: |
7 | * 1. Redistributions of source code must retain the above copyright |
8 | * notice, this list of conditions and the following disclaimer. |
9 | * 2. Redistributions in binary form must reproduce the above copyright |
10 | * notice, this list of conditions and the following disclaimer in the |
11 | * documentation and/or other materials provided with the distribution. |
12 | * |
13 | * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' |
14 | * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, |
15 | * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
16 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS |
17 | * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
18 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
19 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
20 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
21 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
22 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF |
23 | * THE POSSIBILITY OF SUCH DAMAGE. |
24 | */ |
25 | |
26 | #pragma once |
27 | |
28 | #include "FloatRect.h" |
29 | #include "ScrollTypes.h" |
30 | |
31 | namespace WebCore { |
32 | |
33 | // LayoutConstraints classes encapsulate data and logic required to reposition elements whose layout |
34 | // depends on the scroll position of ancestor elements. |
35 | class LayoutConstraints { |
36 | WTF_MAKE_FAST_ALLOCATED; |
37 | public: |
38 | LayoutConstraints() = default; |
39 | |
40 | bool operator==(const LayoutConstraints& other) const |
41 | { |
42 | return alignmentOffset() == other.alignmentOffset() |
43 | && layerPositionAtLastLayout() == other.layerPositionAtLastLayout() |
44 | && scrollPositioningBehavior() == other.scrollPositioningBehavior(); |
45 | } |
46 | |
47 | bool operator!=(const LayoutConstraints& other) const { return !(*this == other); } |
48 | |
49 | FloatSize alignmentOffset() const { return m_alignmentOffset; } |
50 | void setAlignmentOffset(FloatSize offset) { m_alignmentOffset = offset; } |
51 | |
52 | FloatPoint layerPositionAtLastLayout() const { return m_layerPositionAtLastLayout; } |
53 | void setLayerPositionAtLastLayout(FloatPoint position) { m_layerPositionAtLastLayout = position; } |
54 | |
55 | ScrollPositioningBehavior scrollPositioningBehavior() const { return m_scrollPositioningBehavior; } |
56 | void setScrollPositioningBehavior(ScrollPositioningBehavior behavior) { m_scrollPositioningBehavior = behavior; } |
57 | |
58 | private: |
59 | FloatSize m_alignmentOffset; |
60 | FloatPoint m_layerPositionAtLastLayout; |
61 | ScrollPositioningBehavior m_scrollPositioningBehavior { ScrollPositioningBehavior::None }; |
62 | }; |
63 | |
64 | // ViewportConstraints classes encapsulate data and logic required to reposition elements whose layout |
65 | // depends on the viewport rect (positions fixed and sticky), when scrolling and zooming. |
66 | class ViewportConstraints { |
67 | WTF_MAKE_FAST_ALLOCATED; |
68 | public: |
69 | enum ConstraintType { |
70 | FixedPositionConstraint, |
71 | StickyPositionConstraint |
72 | }; |
73 | |
74 | enum AnchorEdgeFlags { |
75 | AnchorEdgeLeft = 1 << 0, |
76 | AnchorEdgeRight = 1 << 1, |
77 | AnchorEdgeTop = 1 << 2, |
78 | AnchorEdgeBottom = 1 << 3 |
79 | }; |
80 | typedef unsigned AnchorEdges; |
81 | |
82 | virtual ~ViewportConstraints() = default; |
83 | |
84 | virtual ConstraintType constraintType() const = 0; |
85 | |
86 | AnchorEdges anchorEdges() const { return m_anchorEdges; } |
87 | bool hasAnchorEdge(AnchorEdgeFlags flag) const { return m_anchorEdges & flag; } |
88 | void addAnchorEdge(AnchorEdgeFlags edgeFlag) { m_anchorEdges |= edgeFlag; } |
89 | void setAnchorEdges(AnchorEdges edges) { m_anchorEdges = edges; } |
90 | |
91 | FloatSize alignmentOffset() const { return m_alignmentOffset; } |
92 | void setAlignmentOffset(FloatSize offset) { m_alignmentOffset = offset; } |
93 | |
94 | protected: |
95 | ViewportConstraints() |
96 | : m_anchorEdges(0) |
97 | { } |
98 | |
99 | FloatSize m_alignmentOffset; |
100 | AnchorEdges m_anchorEdges; |
101 | }; |
102 | |
103 | class FixedPositionViewportConstraints : public ViewportConstraints { |
104 | public: |
105 | FixedPositionViewportConstraints() |
106 | : ViewportConstraints() |
107 | { } |
108 | |
109 | WEBCORE_EXPORT FloatPoint layerPositionForViewportRect(const FloatRect& viewportRect) const; |
110 | |
111 | const FloatRect& viewportRectAtLastLayout() const { return m_viewportRectAtLastLayout; } |
112 | void setViewportRectAtLastLayout(const FloatRect& rect) { m_viewportRectAtLastLayout = rect; } |
113 | |
114 | const FloatPoint& layerPositionAtLastLayout() const { return m_layerPositionAtLastLayout; } |
115 | void setLayerPositionAtLastLayout(FloatPoint position) { m_layerPositionAtLastLayout = position; } |
116 | |
117 | bool operator==(const FixedPositionViewportConstraints& other) const |
118 | { |
119 | return m_alignmentOffset == other.m_alignmentOffset |
120 | && m_anchorEdges == other.m_anchorEdges |
121 | && m_viewportRectAtLastLayout == other.m_viewportRectAtLastLayout |
122 | && m_layerPositionAtLastLayout == other.m_layerPositionAtLastLayout; |
123 | } |
124 | |
125 | bool operator!=(const FixedPositionViewportConstraints& other) const { return !(*this == other); } |
126 | |
127 | private: |
128 | ConstraintType constraintType() const override { return FixedPositionConstraint; }; |
129 | |
130 | FloatRect m_viewportRectAtLastLayout; |
131 | FloatPoint m_layerPositionAtLastLayout; |
132 | }; |
133 | |
134 | class StickyPositionViewportConstraints : public ViewportConstraints { |
135 | public: |
136 | StickyPositionViewportConstraints() |
137 | : m_leftOffset(0) |
138 | , m_rightOffset(0) |
139 | , m_topOffset(0) |
140 | , m_bottomOffset(0) |
141 | { } |
142 | |
143 | FloatSize computeStickyOffset(const FloatRect& constrainingRect) const; |
144 | |
145 | const FloatSize stickyOffsetAtLastLayout() const { return m_stickyOffsetAtLastLayout; } |
146 | void setStickyOffsetAtLastLayout(FloatSize offset) { m_stickyOffsetAtLastLayout = offset; } |
147 | |
148 | WEBCORE_EXPORT FloatPoint layerPositionForConstrainingRect(const FloatRect& constrainingRect) const; |
149 | |
150 | const FloatPoint& layerPositionAtLastLayout() const { return m_layerPositionAtLastLayout; } |
151 | void setLayerPositionAtLastLayout(FloatPoint position) { m_layerPositionAtLastLayout = position; } |
152 | |
153 | float leftOffset() const { return m_leftOffset; } |
154 | float rightOffset() const { return m_rightOffset; } |
155 | float topOffset() const { return m_topOffset; } |
156 | float bottomOffset() const { return m_bottomOffset; } |
157 | |
158 | void setLeftOffset(float offset) { m_leftOffset = offset; } |
159 | void setRightOffset(float offset) { m_rightOffset = offset; } |
160 | void setTopOffset(float offset) { m_topOffset = offset; } |
161 | void setBottomOffset(float offset) { m_bottomOffset = offset; } |
162 | |
163 | // constrainingRectAtLastLayout() is the viewport rect if this sticky object sticks to the viewport, and |
164 | // it is the overflow area's scrolled clip rect if this sticky object sticks inside an overflow area. |
165 | FloatRect constrainingRectAtLastLayout() const { return m_constrainingRectAtLastLayout; } |
166 | void setConstrainingRectAtLastLayout(const FloatRect& rect) { m_constrainingRectAtLastLayout = rect; } |
167 | |
168 | // containingBlockRect() is in the scrolling ancestor's coordinate space. |
169 | FloatRect containingBlockRect() const { return m_containingBlockRect; } |
170 | void setContainingBlockRect(const FloatRect& rect) { m_containingBlockRect = rect; } |
171 | |
172 | // stickyBoxRect() is in the scrolling ancestor's coordinate space. |
173 | FloatRect stickyBoxRect() const { return m_stickyBoxRect; } |
174 | void setStickyBoxRect(const FloatRect& rect) { m_stickyBoxRect = rect; } |
175 | |
176 | bool operator==(const StickyPositionViewportConstraints& other) const |
177 | { |
178 | return m_alignmentOffset == other.m_alignmentOffset |
179 | && m_anchorEdges == other.m_anchorEdges |
180 | && m_leftOffset == other.m_leftOffset |
181 | && m_rightOffset == other.m_rightOffset |
182 | && m_topOffset == other.m_topOffset |
183 | && m_bottomOffset == other.m_bottomOffset |
184 | && m_containingBlockRect == other.m_containingBlockRect |
185 | && m_stickyBoxRect == other.m_stickyBoxRect |
186 | && m_stickyOffsetAtLastLayout == other.m_stickyOffsetAtLastLayout |
187 | && m_layerPositionAtLastLayout == other.m_layerPositionAtLastLayout; |
188 | } |
189 | |
190 | bool operator!=(const StickyPositionViewportConstraints& other) const { return !(*this == other); } |
191 | |
192 | private: |
193 | ConstraintType constraintType() const override { return StickyPositionConstraint; }; |
194 | |
195 | float m_leftOffset; |
196 | float m_rightOffset; |
197 | float m_topOffset; |
198 | float m_bottomOffset; |
199 | FloatRect m_constrainingRectAtLastLayout; |
200 | FloatRect m_containingBlockRect; |
201 | FloatRect m_stickyBoxRect; |
202 | FloatSize m_stickyOffsetAtLastLayout; |
203 | FloatPoint m_layerPositionAtLastLayout; |
204 | }; |
205 | |
206 | |
207 | WEBCORE_EXPORT WTF::TextStream& operator<<(WTF::TextStream&, ScrollPositioningBehavior); |
208 | WEBCORE_EXPORT WTF::TextStream& operator<<(WTF::TextStream&, const LayoutConstraints&); |
209 | WEBCORE_EXPORT WTF::TextStream& operator<<(WTF::TextStream&, const FixedPositionViewportConstraints&); |
210 | WEBCORE_EXPORT WTF::TextStream& operator<<(WTF::TextStream&, const StickyPositionViewportConstraints&); |
211 | |
212 | } // namespace WebCore |
213 | |