1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
|
/*
* Copyright (C) 2022 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
#if ENABLE(LAYOUT_FORMATTING_CONTEXT)
#include "FlexFormattingConstraints.h"
#include "FlexFormattingState.h"
#include "FlexRect.h"
#include <wtf/Range.h>
namespace WebCore {
namespace Layout {
// This class implements the layout logic for flex formatting contexts.
// https://www.w3.org/TR/css-flexbox-1/
class FlexLayout {
public:
FlexLayout(const ContainerBox& flexBox);
struct LogicalFlexItem {
public:
struct LogicalTypes {
LengthType width { LengthType::Auto };
LengthType height { LengthType::Auto };
LengthType leftMargin { LengthType::Auto };
LengthType rightMargin { LengthType::Auto };
LengthType topMargin { LengthType::Auto };
LengthType bottomMargin { LengthType::Auto };
};
LogicalFlexItem(LayoutSize marginBoxSize, LogicalTypes, IntrinsicWidthConstraints, const ContainerBox&);
LogicalFlexItem() = default;
LayoutUnit flexBasis() const { return m_marginBoxSize.width(); }
LayoutUnit width() const { return std::min(maximumSize(), std::max(minimumSize(), m_marginBoxSize.width())); }
LayoutUnit height() const { return m_marginBoxSize.height(); }
bool isHeightAuto() const { return m_logicalTypes.height == LengthType::Auto; }
bool hasAutoMarginLeft() const { return m_logicalTypes.leftMargin == LengthType::Auto; }
bool hasAutoMarginRight() const { return m_logicalTypes.rightMargin == LengthType::Auto; }
bool hasAutoMarginTop() const { return m_logicalTypes.topMargin == LengthType::Auto; }
bool hasAutoMarginBottom() const { return m_logicalTypes.bottomMargin == LengthType::Auto; }
LayoutUnit minimumSize() const { return m_intrinsicWidthConstraints.minimum; }
LayoutUnit maximumSize() const { return m_intrinsicWidthConstraints.maximum; }
const RenderStyle& style() const { return m_layoutBox->style(); }
const ContainerBox& layoutBox() const { return *m_layoutBox; }
private:
LayoutSize m_marginBoxSize;
LogicalTypes m_logicalTypes { };
IntrinsicWidthConstraints m_intrinsicWidthConstraints { };
CheckedPtr<const ContainerBox> m_layoutBox;
};
using LogicalFlexItems = Vector<LogicalFlexItem>;
struct LogicalConstraints {
std::optional<LayoutUnit> verticalSpace;
struct HorizontalSpace {
std::optional<LayoutUnit> available; // This is how much space there is for flexing in main axis direction.
std::optional<LayoutUnit> minimum; // This is how much space is at least available for flexing in main axis direction.
};
HorizontalSpace horizontalSpace;
};
struct FlexItemRect {
FlexRect& operator()() { return marginRect; }
FlexRect marginRect;
struct AutoMargin {
std::optional<LayoutUnit> left;
std::optional<LayoutUnit> right;
std::optional<LayoutUnit> top;
std::optional<LayoutUnit> bottom;
};
AutoMargin autoMargin;
};
using LogicalFlexItemRects = Vector<FlexItemRect>;
LogicalFlexItemRects layout(const LogicalConstraints&, const LogicalFlexItems&);
private:
using LineRange = WTF::Range<size_t>;
void computeLogicalWidthForFlexItems(const LogicalFlexItems&, const LineRange&, LayoutUnit availableSpace, LogicalFlexItemRects&);
void computeLogicalWidthForStretchingFlexItems(const LogicalFlexItems&, const LineRange&, LayoutUnit availableSpace, LogicalFlexItemRects&);
void computeLogicalWidthForShrinkingFlexItems(const LogicalFlexItems&, const LineRange&, LayoutUnit availableSpace, LogicalFlexItemRects&);
void computeLogicalHeightForFlexItems(const LogicalFlexItems&, const LineRange&, LayoutUnit availableSpace, LogicalFlexItemRects&);
void alignFlexItems(const LogicalFlexItems&, const LineRange&, VerticalConstraints, LogicalFlexItemRects&);
void justifyFlexItems(const LogicalFlexItems&, const LineRange&, LayoutUnit availableSpace, LogicalFlexItemRects&);
void distributeMarginAutoInMainAxis(const LogicalFlexItems&, const LineRange&, LayoutUnit availableSpace, LogicalFlexItemRects&);
void distributeMarginAutoInCrossAxis(const LogicalFlexItems&, const LineRange&, LayoutUnit availableSpace, LogicalFlexItemRects&);
using WrappingPositions = Vector<size_t>;
WrappingPositions computeWrappingPositions(const LogicalFlexItems&, LayoutUnit availableSpace) const;
LayoutUnit computeAvailableLogicalHorizontalSpace(const LogicalFlexItems&, const LogicalConstraints&) const;
using LineHeightList = Vector<LayoutUnit>;
LineHeightList computeAvailableLogicalVerticalSpace(const LogicalFlexItems&, const WrappingPositions&, const LogicalConstraints&) const;
const ContainerBox& flexBox() const { return m_flexBox; }
const RenderStyle& flexBoxStyle() const { return flexBox().style(); }
const ContainerBox& m_flexBox;
};
inline FlexLayout::LogicalFlexItem::LogicalFlexItem(LayoutSize marginBoxSize, LogicalTypes logicalTypes, IntrinsicWidthConstraints intrinsicWidthConstraints, const ContainerBox& layoutBox)
: m_marginBoxSize(marginBoxSize)
, m_logicalTypes(logicalTypes)
, m_intrinsicWidthConstraints(intrinsicWidthConstraints)
, m_layoutBox(layoutBox)
{
}
}
}
#endif
|
