1 // Copyright 2014 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "ui/gfx/font_list_impl.h"
6
7 #include <stddef.h>
8
9 #include <algorithm>
10
11 #include "base/check_op.h"
12 #include "base/strings/string_number_conversions.h"
13 #include "base/strings/string_util.h"
14 #include "ui/gfx/font_list.h"
15
16 namespace gfx {
17 namespace {
18
19 // Returns a font description from |families|, |style|, and |size_pixels|.
BuildDescription(const std::vector<std::string> & families,int style,int size_pixels,Font::Weight weight)20 std::string BuildDescription(const std::vector<std::string>& families,
21 int style,
22 int size_pixels,
23 Font::Weight weight) {
24 std::string description = base::JoinString(families, ",");
25 description += ",";
26
27 if (style & Font::ITALIC)
28 description += "Italic ";
29 switch (weight) {
30 case Font::Weight::THIN:
31 description += "Thin ";
32 break;
33 case Font::Weight::EXTRA_LIGHT:
34 description += "Ultra-Light ";
35 break;
36 case Font::Weight::LIGHT:
37 description += "Light ";
38 break;
39 case Font::Weight::MEDIUM:
40 description += "Medium ";
41 break;
42 case Font::Weight::SEMIBOLD:
43 description += "Semi-Bold ";
44 break;
45 case Font::Weight::BOLD:
46 description += "Bold ";
47 break;
48 case Font::Weight::EXTRA_BOLD:
49 description += "Ultra-Bold ";
50 break;
51 case Font::Weight::BLACK:
52 description += "Heavy ";
53 break;
54 case Font::Weight::NORMAL:
55 case Font::Weight::INVALID:
56 break;
57 }
58
59 description += base::NumberToString(size_pixels);
60 description += "px";
61
62 return description;
63 }
64
65 } // namespace
66
FontListImpl(const std::string & font_description_string)67 FontListImpl::FontListImpl(const std::string& font_description_string)
68 : font_description_string_(font_description_string),
69 common_height_(-1),
70 common_baseline_(-1),
71 font_style_(-1),
72 font_size_(-1),
73 font_weight_(Font::Weight::INVALID) {
74 DCHECK(!font_description_string.empty());
75 // DCHECK description string ends with "px" for size in pixel.
76 DCHECK(base::EndsWith(font_description_string, "px",
77 base::CompareCase::SENSITIVE));
78 }
79
FontListImpl(const std::vector<std::string> & font_names,int font_style,int font_size,Font::Weight font_weight)80 FontListImpl::FontListImpl(const std::vector<std::string>& font_names,
81 int font_style,
82 int font_size,
83 Font::Weight font_weight)
84 : font_description_string_(
85 BuildDescription(font_names, font_style, font_size, font_weight)),
86 common_height_(-1),
87 common_baseline_(-1),
88 font_style_(font_style),
89 font_size_(font_size),
90 font_weight_(font_weight) {
91 DCHECK(!font_names.empty());
92 DCHECK(!font_names[0].empty());
93 }
94
FontListImpl(const std::vector<Font> & fonts)95 FontListImpl::FontListImpl(const std::vector<Font>& fonts)
96 : fonts_(fonts),
97 common_height_(-1),
98 common_baseline_(-1),
99 font_style_(-1),
100 font_size_(-1),
101 font_weight_(Font::Weight::INVALID) {
102 DCHECK(!fonts.empty());
103 font_style_ = fonts[0].GetStyle();
104 font_size_ = fonts[0].GetFontSize();
105 font_weight_ = fonts[0].GetWeight();
106 #if DCHECK_IS_ON()
107 for (size_t i = 1; i < fonts.size(); ++i) {
108 DCHECK_EQ(fonts[i].GetStyle(), font_style_);
109 DCHECK_EQ(fonts[i].GetFontSize(), font_size_);
110 }
111 #endif
112 }
113
FontListImpl(const Font & font)114 FontListImpl::FontListImpl(const Font& font)
115 : common_height_(-1),
116 common_baseline_(-1),
117 font_style_(-1),
118 font_size_(-1),
119 font_weight_(Font::Weight::INVALID) {
120 fonts_.push_back(font);
121 }
122
Derive(int size_delta,int font_style,Font::Weight weight) const123 FontListImpl* FontListImpl::Derive(int size_delta,
124 int font_style,
125 Font::Weight weight) const {
126 // If there is a font vector, derive from that.
127 if (!fonts_.empty()) {
128 std::vector<Font> fonts = fonts_;
129 for (size_t i = 0; i < fonts.size(); ++i)
130 fonts[i] = fonts[i].Derive(size_delta, font_style, weight);
131 return new FontListImpl(fonts);
132 }
133
134 // Otherwise, parse the font description string to derive from it.
135 std::vector<std::string> font_names;
136 int old_size;
137 int old_style;
138 Font::Weight old_weight;
139 CHECK(FontList::ParseDescription(font_description_string_, &font_names,
140 &old_style, &old_size, &old_weight));
141 const int size = std::max(1, old_size + size_delta);
142 return new FontListImpl(font_names, font_style, size, weight);
143 }
144
GetHeight() const145 int FontListImpl::GetHeight() const {
146 if (common_height_ == -1)
147 CacheCommonFontHeightAndBaseline();
148 return common_height_;
149 }
150
GetBaseline() const151 int FontListImpl::GetBaseline() const {
152 if (common_baseline_ == -1)
153 CacheCommonFontHeightAndBaseline();
154 return common_baseline_;
155 }
156
GetCapHeight() const157 int FontListImpl::GetCapHeight() const {
158 // Assume the primary font is used to render Latin characters.
159 return GetPrimaryFont().GetCapHeight();
160 }
161
GetExpectedTextWidth(int length) const162 int FontListImpl::GetExpectedTextWidth(int length) const {
163 // Rely on the primary font metrics for the time being.
164 return GetPrimaryFont().GetExpectedTextWidth(length);
165 }
166
GetFontStyle() const167 int FontListImpl::GetFontStyle() const {
168 if (font_style_ == -1)
169 CacheFontStyleAndSize();
170 return font_style_;
171 }
172
GetFontSize() const173 int FontListImpl::GetFontSize() const {
174 if (font_size_ == -1)
175 CacheFontStyleAndSize();
176 return font_size_;
177 }
178
GetFontWeight() const179 Font::Weight FontListImpl::GetFontWeight() const {
180 if (font_weight_ == Font::Weight::INVALID)
181 CacheFontStyleAndSize();
182 return font_weight_;
183 }
184
GetFonts() const185 const std::vector<Font>& FontListImpl::GetFonts() const {
186 if (fonts_.empty()) {
187 DCHECK(!font_description_string_.empty());
188
189 std::vector<std::string> font_names;
190 // It's possible that Font::UNDERLINE is specified and it's already
191 // stored in |font_style_| but |font_description_string_| doesn't have the
192 // underline info. So we should respect |font_style_| as long as it's
193 // valid.
194 int style = 0;
195 CHECK(FontList::ParseDescription(font_description_string_, &font_names,
196 &style, &font_size_, &font_weight_));
197 if (font_style_ == -1)
198 font_style_ = style;
199 for (size_t i = 0; i < font_names.size(); ++i) {
200 DCHECK(!font_names[i].empty());
201
202 Font font(font_names[i], font_size_);
203 if (font_style_ == Font::NORMAL && font_weight_ == Font::Weight::NORMAL)
204 fonts_.push_back(font);
205 else
206 fonts_.push_back(font.Derive(0, font_style_, font_weight_));
207 }
208 }
209 return fonts_;
210 }
211
GetPrimaryFont() const212 const Font& FontListImpl::GetPrimaryFont() const {
213 return GetFonts()[0];
214 }
215
~FontListImpl()216 FontListImpl::~FontListImpl() {}
217
CacheCommonFontHeightAndBaseline() const218 void FontListImpl::CacheCommonFontHeightAndBaseline() const {
219 int ascent = 0;
220 int descent = 0;
221 const std::vector<Font>& fonts = GetFonts();
222 for (auto i = fonts.begin(); i != fonts.end(); ++i) {
223 ascent = std::max(ascent, i->GetBaseline());
224 descent = std::max(descent, i->GetHeight() - i->GetBaseline());
225 }
226 common_height_ = ascent + descent;
227 common_baseline_ = ascent;
228 }
229
CacheFontStyleAndSize() const230 void FontListImpl::CacheFontStyleAndSize() const {
231 if (!fonts_.empty()) {
232 font_style_ = fonts_[0].GetStyle();
233 font_size_ = fonts_[0].GetFontSize();
234 font_weight_ = fonts_[0].GetWeight();
235 } else {
236 std::vector<std::string> font_names;
237 CHECK(FontList::ParseDescription(font_description_string_, &font_names,
238 &font_style_, &font_size_, &font_weight_));
239 }
240 }
241
242 } // namespace gfx
243