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
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
|
/*
* Copyright (C) 2025 Samuel Weinig <sam@webkit.org>
* Copyright (C) 2025 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. ``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
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* 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
#include <WebCore/FloatRect.h>
#include <WebCore/LayoutRect.h>
#include <WebCore/WritingMode.h>
#include <wtf/FixedVector.h>
namespace WebCore {
namespace Style {
enum class ShadowStyle : bool { Normal, Inset };
template<typename T> concept Shadow = requires(const T& shadow, const Style::ZoomFactor& zoomFactor) {
{ shadowStyle(shadow) } -> std::same_as<ShadowStyle>;
{ isInset(shadow) } -> std::same_as<bool>;
{ paintingSpread(shadow, zoomFactor) } -> std::same_as<LayoutUnit>;
};
template<typename ShadowType> using ShadowList = CommaSeparatedFixedVector<ShadowType>;
template<typename ShadowType> struct Shadows : ListOrNone<ShadowList<ShadowType>> { using ListOrNone<ShadowList<ShadowType>>::ListOrNone; };
LayoutUnit paintingExtent(Shadow auto const& shadow, const Style::ZoomFactor& zoomFactor)
{
// Blurring uses a Gaussian function whose std. deviation is m_radius/2, and which in theory
// extends to infinity. In 8-bit contexts, however, rounding causes the effect to become
// undetectable at around 1.4x the radius.
constexpr const float radiusExtentMultiplier = 1.4;
return LayoutUnit { ceilf(shadow.blur.resolveZoom(zoomFactor) * radiusExtentMultiplier) };
}
LayoutUnit paintingExtentAndSpread(Shadow auto const& shadow, const Style::ZoomFactor& zoomFactor)
{
return paintingExtent(shadow, zoomFactor) + paintingSpread(shadow, zoomFactor);
}
template<Shadow ShadowType> auto shadowOutsetExtent(const Shadows<ShadowType>& shadows, const Style::ZoomFactor& zoomFactor) -> LayoutBoxExtent
{
LayoutUnit top;
LayoutUnit right;
LayoutUnit bottom;
LayoutUnit left;
for (const auto& shadow : shadows) {
if (isInset(shadow))
continue;
auto extentAndSpread = paintingExtentAndSpread(shadow, zoomFactor);
left = std::min<LayoutUnit>(left, LayoutUnit(shadow.location.x().resolveZoom(zoomFactor)) - extentAndSpread);
right = std::max<LayoutUnit>(right, LayoutUnit(shadow.location.x().resolveZoom(zoomFactor)) + extentAndSpread);
top = std::min<LayoutUnit>(top, LayoutUnit(shadow.location.y().resolveZoom(zoomFactor)) - extentAndSpread);
bottom = std::max<LayoutUnit>(bottom, LayoutUnit(shadow.location.y().resolveZoom(zoomFactor)) + extentAndSpread);
}
return { top, right, bottom, left };
}
template<Shadow ShadowType> auto shadowInsetExtent(const Shadows<ShadowType>& shadows, const Style::ZoomFactor& zoomFactor) -> LayoutBoxExtent
{
LayoutUnit top;
LayoutUnit right;
LayoutUnit bottom;
LayoutUnit left;
for (const auto& shadow : shadows) {
if (!isInset(shadow))
continue;
auto extentAndSpread = paintingExtentAndSpread(shadow, zoomFactor);
top = std::max<LayoutUnit>(top, LayoutUnit(shadow.location.y().resolveZoom(zoomFactor)) + extentAndSpread);
right = std::min<LayoutUnit>(right, LayoutUnit(shadow.location.x().resolveZoom(zoomFactor)) - extentAndSpread);
bottom = std::min<LayoutUnit>(bottom, LayoutUnit(shadow.location.y().resolveZoom(zoomFactor)) - extentAndSpread);
left = std::max<LayoutUnit>(left, LayoutUnit(shadow.location.x().resolveZoom(zoomFactor)) + extentAndSpread);
}
return { top, right, bottom, left };
}
template<Shadow ShadowType> auto shadowHorizontalExtent(const Shadows<ShadowType>& shadows, const Style::ZoomFactor& zoomFactor) -> std::pair<LayoutUnit, LayoutUnit>
{
LayoutUnit left = 0;
LayoutUnit right = 0;
for (const auto& shadow : shadows) {
if (isInset(shadow))
continue;
auto extentAndSpread = paintingExtentAndSpread(shadow, zoomFactor);
left = std::min<LayoutUnit>(left, LayoutUnit(shadow.location.x().resolveZoom(zoomFactor)) - extentAndSpread);
right = std::max<LayoutUnit>(right, LayoutUnit(shadow.location.x().resolveZoom(zoomFactor)) + extentAndSpread);
}
return { left, right };
}
template<Shadow ShadowType> auto shadowVerticalExtent(const Shadows<ShadowType>& shadows, const Style::ZoomFactor& zoomFactor) -> std::pair<LayoutUnit, LayoutUnit>
{
LayoutUnit top = 0;
LayoutUnit bottom = 0;
for (const auto& shadow : shadows) {
if (isInset(shadow))
continue;
auto extentAndSpread = paintingExtentAndSpread(shadow, zoomFactor);
// FIXME: Why does this do a static cast to `int` but all of the other "extent" functions in this file do not?
top = std::min<LayoutUnit>(top, LayoutUnit(static_cast<int>(shadow.location.y().resolveZoom(zoomFactor))) - extentAndSpread);
bottom = std::max<LayoutUnit>(bottom, LayoutUnit(static_cast<int>(shadow.location.y().resolveZoom(zoomFactor))) + extentAndSpread);
}
return { top, bottom };
}
template<Shadow ShadowType> auto shadowBlockDirectionExtent(const Shadows<ShadowType>& shadows, WritingMode writingMode, const Style::ZoomFactor& zoomFactor) -> std::pair<LayoutUnit, LayoutUnit>
{
return writingMode.isHorizontal() ? shadowVerticalExtent(shadows, zoomFactor) : shadowHorizontalExtent(shadows, zoomFactor);
}
template<Shadow ShadowType> auto shadowInlineDirectionExtent(const Shadows<ShadowType>& shadows, WritingMode writingMode, const Style::ZoomFactor& zoomFactor) -> std::pair<LayoutUnit, LayoutUnit>
{
return writingMode.isHorizontal() ? shadowHorizontalExtent(shadows, zoomFactor) : shadowVerticalExtent(shadows, zoomFactor);
}
template<Shadow ShadowType> void adjustRectForShadow(LayoutRect& rect, const Shadows<ShadowType>& shadows, const Style::ZoomFactor& zoomFactor)
{
auto shadowExtent = shadowOutsetExtent(shadows, zoomFactor);
rect.move(shadowExtent.left(), shadowExtent.top());
rect.setWidth(rect.width() - shadowExtent.left() + shadowExtent.right());
rect.setHeight(rect.height() - shadowExtent.top() + shadowExtent.bottom());
}
template<Shadow ShadowType> void adjustRectForShadow(FloatRect& rect, const Shadows<ShadowType>& shadows, const Style::ZoomFactor& zoomFactor)
{
auto shadowExtent = shadowOutsetExtent(shadows, zoomFactor);
rect.move(shadowExtent.left(), shadowExtent.top());
rect.setWidth(rect.width() - shadowExtent.left() + shadowExtent.right());
rect.setHeight(rect.height() - shadowExtent.top() + shadowExtent.bottom());
}
} // namespace Style
} // namespace WebCore
|
