1 // Copyright (c) 2012 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 #ifndef UI_GFX_FONT_LIST_H_ 6 #define UI_GFX_FONT_LIST_H_ 7 8 #include <string> 9 #include <vector> 10 11 #include "ui/base/ui_export.h" 12 #include "ui/gfx/font.h" 13 14 namespace gfx { 15 16 // FontList represents a list of fonts either in the form of Font vector or in 17 // the form of a string representing font names, styles, and size. 18 // 19 // The string representation is in the form "FAMILY_LIST [STYLE_OPTIONS] SIZE", 20 // where FAMILY_LIST is a comma separated list of families terminated by a 21 // comma, STYLE_OPTIONS is a whitespace separated list of words where each word 22 // describes one of style, variant, weight, stretch, or gravity, and SIZE is 23 // a decimal number followed by "px" for absolute size. STYLE_OPTIONS may be 24 // absent. 25 // 26 // The string format complies with that of Pango detailed at 27 // http://developer.gnome.org/pango/stable/pango-Fonts.html#pango-font-description-from-string 28 // 29 // FontList could be initialized either way without conversion to the other 30 // form. The conversion to the other form is done only when asked to get the 31 // other form. 32 // 33 // FontList allows operator= since FontList is a data member type in RenderText, 34 // and operator= is used in RenderText::SetFontList(). 35 class UI_EXPORT FontList { 36 public: 37 // Creates a font list with a Font with default name and style. 38 FontList(); 39 40 // Creates a font list from a string representing font names, styles, and 41 // size. 42 explicit FontList(const std::string& font_description_string); 43 44 // Creates a font list from font names, styles and size. 45 FontList(const std::vector<std::string>& font_names, 46 int font_style, 47 int font_size); 48 49 // Creates a font list from a Font vector. 50 // All fonts in this vector should have the same style and size. 51 explicit FontList(const std::vector<Font>& fonts); 52 53 // Creates a font list from a Font. 54 explicit FontList(const Font& font); 55 56 ~FontList(); 57 58 // Returns a new FontList with the given |font_style| flags. 59 FontList DeriveFontList(int font_style) const; 60 61 // Returns a new FontList with the same font names and style but with the 62 // given font |size| in pixels. 63 FontList DeriveFontListWithSize(int size) const; 64 65 // Returns a new FontList with the same font names and style but resized. 66 // |size_delta| is the size in pixels to add to the current font size. 67 FontList DeriveFontListWithSizeDelta(int size_delta) const; 68 69 // Returns a new FontList with the same font names but resized and the given 70 // style. |size_delta| is the size in pixels to add to the current font size. 71 // |font_style| specifies the new style, which is a bitmask of the values: 72 // Font::BOLD, Font::ITALIC and Font::UNDERLINE. 73 FontList DeriveFontListWithSizeDeltaAndStyle(int size_delta, 74 int font_style) const; 75 76 // Returns the height of this font list, which is max(ascent) + max(descent) 77 // for all the fonts in the font list. 78 int GetHeight() const; 79 80 // Returns the baseline of this font list, which is max(baseline) for all the 81 // fonts in the font list. 82 int GetBaseline() const; 83 84 // Returns the number of horizontal pixels needed to display |text|. 85 int GetStringWidth(const base::string16& text) const; 86 87 // Returns the expected number of horizontal pixels needed to display the 88 // specified length of characters. Call GetStringWidth() to retrieve the 89 // actual number. 90 int GetExpectedTextWidth(int length) const; 91 92 // Returns the |gfx::Font::FontStyle| style flags for this font list. 93 int GetFontStyle() const; 94 95 // Returns a string representing font names, styles, and size. If the FontList 96 // is initialized by a vector of Font, use the first font's style and size 97 // for the description. 98 const std::string& GetFontDescriptionString() const; 99 100 // Returns the font size in pixels. 101 int GetFontSize() const; 102 103 // Returns the Font vector. 104 const std::vector<Font>& GetFonts() const; 105 106 // Returns the first font in the list. 107 const Font& GetPrimaryFont() const; 108 109 private: 110 // Extracts common font height and baseline into |common_height_| and 111 // |common_baseline_|. 112 void CacheCommonFontHeightAndBaseline() const; 113 114 // Extracts font style and size into |font_style_| and |font_size_|. 115 void CacheFontStyleAndSize() const; 116 117 // A vector of Font. If FontList is constructed with font description string, 118 // |fonts_| is not initialized during construction. Instead, it is computed 119 // lazily when user asked to get the font vector. 120 mutable std::vector<Font> fonts_; 121 122 // A string representing font names, styles, and sizes. 123 // Please refer to the comments before class declaration for details on string 124 // format. 125 // If FontList is constructed with a vector of font, 126 // |font_description_string_| is not initialized during construction. Instead, 127 // it is computed lazily when user asked to get the font description string. 128 mutable std::string font_description_string_; 129 130 // The cached common height and baseline of the fonts in the font list. 131 mutable int common_height_; 132 mutable int common_baseline_; 133 134 // Cached font style and size. 135 mutable int font_style_; 136 mutable int font_size_; 137 }; 138 139 } // namespace gfx 140 141 #endif // UI_GFX_FONT_LIST_H_ 142
