| // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef UI_GFX_FONT_H_ |
| #define UI_GFX_FONT_H_ |
| |
| #include <string> |
| |
| #include "base/memory/ref_counted.h" |
| #include "base/strings/string16.h" |
| #include "ui/gfx/gfx_export.h" |
| #include "ui/gfx/native_widget_types.h" |
| |
| namespace gfx { |
| |
| class PlatformFont; |
| |
| // Font provides a wrapper around an underlying font. Copy and assignment |
| // operators are explicitly allowed, and cheap. |
| // |
| // Figure of font metrics: |
| // +--------+-------------------+------------------+ |
| // | | | internal leading | |
| // | | ascent (baseline) +------------------+ |
| // | height | | cap height | |
| // | |-------------------+------------------+ |
| // | | descent (height - baseline) | |
| // +--------+--------------------------------------+ |
| class GFX_EXPORT Font { |
| public: |
| // The following constants indicate the font style. |
| enum FontStyle { |
| NORMAL = 0, |
| BOLD = 1, |
| ITALIC = 2, |
| UNDERLINE = 4, |
| }; |
| |
| // Creates a font with the default name and style. |
| Font(); |
| |
| // Creates a font that is a clone of another font object. |
| Font(const Font& other); |
| Font& operator=(const Font& other); |
| |
| // Creates a font from the specified native font. |
| explicit Font(NativeFont native_font); |
| |
| // Constructs a Font object with the specified PlatformFont object. The Font |
| // object takes ownership of the PlatformFont object. |
| explicit Font(PlatformFont* platform_font); |
| |
| // Creates a font with the specified name in UTF-8 and size in pixels. |
| Font(const std::string& font_name, int font_size); |
| |
| ~Font(); |
| |
| // Returns a new Font derived from the existing font. |
| // |size_delta| is the size in pixels to add to the current font. For example, |
| // a value of 5 results in a font 5 pixels bigger than this font. |
| // The style parameter specifies the new style for the font, and is a |
| // bitmask of the values: BOLD, ITALIC and UNDERLINE. |
| Font Derive(int size_delta, int style) const; |
| |
| // Returns the number of vertical pixels needed to display characters from |
| // the specified font. This may include some leading, i.e. height may be |
| // greater than just ascent + descent. Specifically, the Windows and Mac |
| // implementations include leading and the Linux one does not. This may |
| // need to be revisited in the future. |
| int GetHeight() const; |
| |
| // Returns the baseline, or ascent, of the font. |
| int GetBaseline() const; |
| |
| // Returns the cap height of the font. |
| int GetCapHeight() const; |
| |
| // Returns the expected number of horizontal pixels needed to display the |
| // specified length of characters. Call gfx::GetStringWidth() to retrieve the |
| // actual number. |
| int GetExpectedTextWidth(int length) const; |
| |
| // Returns the style of the font. |
| int GetStyle() const; |
| |
| // Returns the specified font name in UTF-8. |
| std::string GetFontName() const; |
| |
| // Returns the actually used font name in UTF-8. |
| std::string GetActualFontNameForTesting() const; |
| |
| // Returns the font size in pixels. |
| int GetFontSize() const; |
| |
| // Returns the native font handle. |
| // Lifetime lore: |
| // Windows: This handle is owned by the Font object, and should not be |
| // destroyed by the caller. |
| // Mac: The object is owned by the system and should not be released. |
| // Gtk: This handle is created on demand, and must be freed by calling |
| // pango_font_description_free() when the caller is done using it or |
| // by using ScopedPangoFontDescription. |
| NativeFont GetNativeFont() const; |
| |
| // Raw access to the underlying platform font implementation. Can be |
| // static_cast to a known implementation type if needed. |
| PlatformFont* platform_font() const { return platform_font_.get(); } |
| |
| private: |
| // Wrapped platform font implementation. |
| scoped_refptr<PlatformFont> platform_font_; |
| }; |
| |
| } // namespace gfx |
| |
| #endif // UI_GFX_FONT_H_ |