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 #ifndef UI_GFX_FONT_LIST_IMPL_H_ 6 #define UI_GFX_FONT_LIST_IMPL_H_ 7 8 #include <string> 9 #include <vector> 10 11 #include "base/memory/ref_counted.h" 12 13 namespace gfx { 14 15 class Font; 16 17 // FontListImpl is designed to provide the implementation of FontList and 18 // intended to be used only from FontList. You must not use this class 19 // directly. 20 // 21 // FontListImpl represents a list of fonts either in the form of Font vector or 22 // in the form of a string representing font names, styles, and size. 23 // 24 // FontListImpl could be initialized either way without conversion to the other 25 // form. The conversion to the other form is done only when asked to get the 26 // other form. 27 // 28 // For the format of font description string, see font_list.h for details. 29 class FontListImpl : public base::RefCounted<FontListImpl> { 30 public: 31 // Creates a font list from a string representing font names, styles, and 32 // size. 33 explicit FontListImpl(const std::string& font_description_string); 34 35 // Creates a font list from font names, styles and size. 36 FontListImpl(const std::vector<std::string>& font_names, 37 int font_style, 38 int font_size); 39 40 // Creates a font list from a Font vector. 41 // All fonts in this vector should have the same style and size. 42 explicit FontListImpl(const std::vector<Font>& fonts); 43 44 // Creates a font list from a Font. 45 explicit FontListImpl(const Font& font); 46 47 // Returns a new FontListImpl with the same font names but resized and the 48 // given style. |size_delta| is the size in pixels to add to the current font 49 // size. |font_style| specifies the new style, which is a bitmask of the 50 // values: Font::BOLD, Font::ITALIC and Font::UNDERLINE. 51 FontListImpl* Derive(int size_delta, int font_style) const; 52 53 // Returns the height of this font list, which is max(ascent) + max(descent) 54 // for all the fonts in the font list. 55 int GetHeight() const; 56 57 // Returns the baseline of this font list, which is max(baseline) for all the 58 // fonts in the font list. 59 int GetBaseline() const; 60 61 // Returns the cap height of this font list. 62 // Currently returns the cap height of the primary font. 63 int GetCapHeight() const; 64 65 // Returns the expected number of horizontal pixels needed to display the 66 // specified length of characters. Call GetStringWidth() to retrieve the 67 // actual number. 68 int GetExpectedTextWidth(int length) const; 69 70 // Returns the |gfx::Font::FontStyle| style flags for this font list. 71 int GetFontStyle() const; 72 73 // Returns a string representing font names, styles, and size. If the 74 // FontListImpl is initialized by a vector of Font, use the first font's style 75 // and size for the description. 76 const std::string& GetFontDescriptionString() const; 77 78 // Returns the font size in pixels. 79 int GetFontSize() const; 80 81 // Returns the Font vector. 82 const std::vector<Font>& GetFonts() const; 83 84 // Returns the first font in the list. 85 const Font& GetPrimaryFont() const; 86 87 private: 88 friend class base::RefCounted<FontListImpl>; 89 90 ~FontListImpl(); 91 92 // Extracts common font height and baseline into |common_height_| and 93 // |common_baseline_|. 94 void CacheCommonFontHeightAndBaseline() const; 95 96 // Extracts font style and size into |font_style_| and |font_size_|. 97 void CacheFontStyleAndSize() const; 98 99 // A vector of Font. If FontListImpl is constructed with font description 100 // string, |fonts_| is not initialized during construction. Instead, it is 101 // computed lazily when user asked to get the font vector. 102 mutable std::vector<Font> fonts_; 103 104 // A string representing font names, styles, and sizes. 105 // Please refer to the comments before class declaration for details on string 106 // format. 107 // If FontListImpl is constructed with a vector of font, 108 // |font_description_string_| is not initialized during construction. Instead, 109 // it is computed lazily when user asked to get the font description string. 110 mutable std::string font_description_string_; 111 112 // The cached common height and baseline of the fonts in the font list. 113 mutable int common_height_; 114 mutable int common_baseline_; 115 116 // Cached font style and size. 117 mutable int font_style_; 118 mutable int font_size_; 119 }; 120 121 } // namespace gfx 122 123 #endif // UI_GFX_FONT_LIST_IMPL_H_ 124