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 | #include "config.h" |
27 | #include "ScrollingConstraints.h" |
28 | |
29 | #include <wtf/text/TextStream.h> |
30 | |
31 | namespace WebCore { |
32 | |
33 | FloatPoint FixedPositionViewportConstraints::layerPositionForViewportRect(const FloatRect& viewportRect) const |
34 | { |
35 | FloatSize offset; |
36 | |
37 | if (hasAnchorEdge(AnchorEdgeLeft)) |
38 | offset.setWidth(viewportRect.x() - m_viewportRectAtLastLayout.x()); |
39 | else if (hasAnchorEdge(AnchorEdgeRight)) |
40 | offset.setWidth(viewportRect.maxX() - m_viewportRectAtLastLayout.maxX()); |
41 | |
42 | if (hasAnchorEdge(AnchorEdgeTop)) |
43 | offset.setHeight(viewportRect.y() - m_viewportRectAtLastLayout.y()); |
44 | else if (hasAnchorEdge(AnchorEdgeBottom)) |
45 | offset.setHeight(viewportRect.maxY() - m_viewportRectAtLastLayout.maxY()); |
46 | |
47 | return m_layerPositionAtLastLayout + offset; |
48 | } |
49 | |
50 | FloatSize StickyPositionViewportConstraints::computeStickyOffset(const FloatRect& constrainingRect) const |
51 | { |
52 | FloatRect boxRect = m_stickyBoxRect; |
53 | |
54 | if (hasAnchorEdge(AnchorEdgeRight)) { |
55 | float rightLimit = constrainingRect.maxX() - m_rightOffset; |
56 | float rightDelta = std::min<float>(0, rightLimit - m_stickyBoxRect.maxX()); |
57 | float availableSpace = std::min<float>(0, m_containingBlockRect.x() - m_stickyBoxRect.x()); |
58 | if (rightDelta < availableSpace) |
59 | rightDelta = availableSpace; |
60 | |
61 | boxRect.move(rightDelta, 0); |
62 | } |
63 | |
64 | if (hasAnchorEdge(AnchorEdgeLeft)) { |
65 | float leftLimit = constrainingRect.x() + m_leftOffset; |
66 | float leftDelta = std::max<float>(0, leftLimit - m_stickyBoxRect.x()); |
67 | float availableSpace = std::max<float>(0, m_containingBlockRect.maxX() - m_stickyBoxRect.maxX()); |
68 | if (leftDelta > availableSpace) |
69 | leftDelta = availableSpace; |
70 | |
71 | boxRect.move(leftDelta, 0); |
72 | } |
73 | |
74 | if (hasAnchorEdge(AnchorEdgeBottom)) { |
75 | float bottomLimit = constrainingRect.maxY() - m_bottomOffset; |
76 | float bottomDelta = std::min<float>(0, bottomLimit - m_stickyBoxRect.maxY()); |
77 | float availableSpace = std::min<float>(0, m_containingBlockRect.y() - m_stickyBoxRect.y()); |
78 | if (bottomDelta < availableSpace) |
79 | bottomDelta = availableSpace; |
80 | |
81 | boxRect.move(0, bottomDelta); |
82 | } |
83 | |
84 | if (hasAnchorEdge(AnchorEdgeTop)) { |
85 | float topLimit = constrainingRect.y() + m_topOffset; |
86 | float topDelta = std::max<float>(0, topLimit - m_stickyBoxRect.y()); |
87 | float availableSpace = std::max<float>(0, m_containingBlockRect.maxY() - m_stickyBoxRect.maxY()); |
88 | if (topDelta > availableSpace) |
89 | topDelta = availableSpace; |
90 | |
91 | boxRect.move(0, topDelta); |
92 | } |
93 | |
94 | return boxRect.location() - m_stickyBoxRect.location(); |
95 | } |
96 | |
97 | FloatPoint StickyPositionViewportConstraints::layerPositionForConstrainingRect(const FloatRect& constrainingRect) const |
98 | { |
99 | FloatSize offset = computeStickyOffset(constrainingRect); |
100 | return m_layerPositionAtLastLayout + offset - m_stickyOffsetAtLastLayout; |
101 | } |
102 | |
103 | TextStream& operator<<(TextStream& ts, ScrollPositioningBehavior behavior) |
104 | { |
105 | switch (behavior) { |
106 | case ScrollPositioningBehavior::None: ts << "none" ; break; |
107 | case ScrollPositioningBehavior::Stationary: ts << "stationary" ; break; |
108 | case ScrollPositioningBehavior::Moves: ts << "moves" ; break; |
109 | } |
110 | return ts; |
111 | } |
112 | |
113 | TextStream& operator<<(TextStream& ts, const LayoutConstraints& constraints) |
114 | { |
115 | ts.dumpProperty("layer-position-at-last-layout" , constraints.layerPositionAtLastLayout()); |
116 | ts.dumpProperty("positioning-behavior" , constraints.scrollPositioningBehavior()); |
117 | |
118 | return ts; |
119 | } |
120 | |
121 | TextStream& operator<<(TextStream& ts, const FixedPositionViewportConstraints& constraints) |
122 | { |
123 | ts.dumpProperty("viewport-rect-at-last-layout" , constraints.viewportRectAtLastLayout()); |
124 | ts.dumpProperty("layer-position-at-last-layout" , constraints.layerPositionAtLastLayout()); |
125 | |
126 | return ts; |
127 | } |
128 | |
129 | TextStream& operator<<(TextStream& ts, const StickyPositionViewportConstraints& constraints) |
130 | { |
131 | ts.dumpProperty("sticky-position-at-last-layout" , constraints.stickyOffsetAtLastLayout()); |
132 | ts.dumpProperty("layer-position-at-last-layout" , constraints.layerPositionAtLastLayout()); |
133 | |
134 | return ts; |
135 | } |
136 | |
137 | } // namespace WebCore |
138 | |