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
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
|
/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* Copyright (c) 2021, sin-ack <sin-ack@protonmail.com>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include "TextLayout.h"
namespace Gfx {
enum class BlockType {
Newline,
Whitespace,
Word
};
struct Block {
BlockType type;
Utf8View characters;
};
FloatRect TextLayout::bounding_rect(TextWrapping wrapping) const
{
auto lines = wrap_lines(TextElision::None, wrapping);
if (lines.is_empty()) {
return {};
}
FloatRect bounding_rect = {
0, 0, 0, (static_cast<float>(lines.size()) * (m_font_metrics.ascent + m_font_metrics.descent + m_font_metrics.line_gap)) - m_font_metrics.line_gap
};
for (auto& line : lines) {
auto line_width = m_font.width(line);
if (line_width > bounding_rect.width())
bounding_rect.set_width(line_width);
}
return bounding_rect;
}
Vector<DeprecatedString, 32> TextLayout::wrap_lines(TextElision elision, TextWrapping wrapping) const
{
Vector<Block> blocks;
Optional<BlockType> current_block_type;
size_t block_start_offset = 0;
size_t offset = 0;
for (auto it = m_text.begin(); !it.done(); ++it) {
offset = m_text.iterator_offset(it);
switch (*it) {
case '\t':
case ' ': {
if (current_block_type.has_value() && current_block_type.value() != BlockType::Whitespace) {
blocks.append({
current_block_type.value(),
m_text.substring_view(block_start_offset, offset - block_start_offset),
});
current_block_type.clear();
}
if (!current_block_type.has_value()) {
current_block_type = BlockType::Whitespace;
block_start_offset = offset;
}
continue;
}
case '\n':
case '\r': {
if (current_block_type.has_value()) {
blocks.append({
current_block_type.value(),
m_text.substring_view(block_start_offset, offset - block_start_offset),
});
current_block_type.clear();
}
blocks.append({ BlockType::Newline, Utf8View {} });
continue;
}
default: {
if (current_block_type.has_value() && current_block_type.value() != BlockType::Word) {
blocks.append({
current_block_type.value(),
m_text.substring_view(block_start_offset, offset - block_start_offset),
});
current_block_type.clear();
}
if (!current_block_type.has_value()) {
current_block_type = BlockType::Word;
block_start_offset = offset;
}
}
}
}
if (current_block_type.has_value()) {
blocks.append({
current_block_type.value(),
m_text.substring_view(block_start_offset, m_text.byte_length() - block_start_offset),
});
}
Vector<DeprecatedString> lines;
StringBuilder builder;
float line_width = 0;
size_t current_block = 0;
for (Block& block : blocks) {
switch (block.type) {
case BlockType::Newline: {
lines.append(builder.to_deprecated_string());
builder.clear();
line_width = 0;
current_block++;
continue;
}
case BlockType::Whitespace:
case BlockType::Word: {
float block_width = m_font.width(block.characters);
// FIXME: This should look at the specific advance amount of the
// last character, but we don't support that yet.
if (current_block != blocks.size() - 1) {
block_width += m_font.glyph_spacing();
}
if (wrapping == TextWrapping::Wrap && line_width + block_width > m_rect.width()) {
lines.append(builder.to_deprecated_string());
builder.clear();
line_width = 0;
}
builder.append(block.characters.as_string());
line_width += block_width;
current_block++;
}
}
}
auto last_line = builder.to_deprecated_string();
if (!last_line.is_empty())
lines.append(last_line);
switch (elision) {
case TextElision::None:
break;
case TextElision::Right: {
lines.at(lines.size() - 1) = elide_text_from_right(Utf8View { lines.at(lines.size() - 1) });
break;
}
}
return lines;
}
DeprecatedString TextLayout::elide_text_from_right(Utf8View text) const
{
float text_width = m_font.width(text);
if (text_width > static_cast<float>(m_rect.width())) {
float ellipsis_width = m_font.width("..."sv);
float current_width = ellipsis_width;
size_t glyph_spacing = m_font.glyph_spacing();
// FIXME: This code will break when the font has glyphs with advance
// amounts different from the actual width of the glyph
// (which is the case with many TrueType fonts).
if (ellipsis_width < text_width) {
size_t offset = 0;
for (auto it = text.begin(); !it.done(); ++it) {
auto code_point = *it;
auto glyph_width = m_font.glyph_or_emoji_width(code_point);
// NOTE: Glyph spacing should not be added after the last glyph on the line,
// but since we are here because the last glyph does not actually fit on the line,
// we don't have to worry about spacing.
auto width_with_this_glyph_included = current_width + glyph_width + glyph_spacing;
if (width_with_this_glyph_included > m_rect.width())
break;
current_width += glyph_width + glyph_spacing;
offset = text.iterator_offset(it);
}
StringBuilder builder;
builder.append(text.substring_view(0, offset).as_string());
builder.append("..."sv);
return builder.to_deprecated_string();
}
}
return text.as_string();
}
}
|
