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_PLATFORM_FONT_H_ 6 #define UI_GFX_PLATFORM_FONT_H_ 7 8 #include <string> 9 10 #include "base/memory/ref_counted.h" 11 #include "base/strings/string16.h" 12 #include "ui/gfx/gfx_export.h" 13 #include "ui/gfx/native_widget_types.h" 14 15 namespace gfx { 16 17 class Font; 18 struct FontRenderParams; 19 20 class GFX_EXPORT PlatformFont : public base::RefCounted<PlatformFont> { 21 public: 22 // Creates an appropriate PlatformFont implementation. 23 static PlatformFont* CreateDefault(); 24 static PlatformFont* CreateFromNativeFont(NativeFont native_font); 25 // Creates a PlatformFont implementation with the specified |font_name| 26 // (encoded in UTF-8) and |font_size| in pixels. 27 static PlatformFont* CreateFromNameAndSize(const std::string& font_name, 28 int font_size); 29 30 // Returns a new Font derived from the existing font. 31 // |size_delta| is the size in pixels to add to the current font. 32 // The style parameter specifies the new style for the font, and is a 33 // bitmask of the values: BOLD, ITALIC and UNDERLINE. 34 virtual Font DeriveFont(int size_delta, int style) const = 0; 35 36 // Returns the number of vertical pixels needed to display characters from 37 // the specified font. This may include some leading, i.e. height may be 38 // greater than just ascent + descent. Specifically, the Windows and Mac 39 // implementations include leading and the Linux one does not. This may 40 // need to be revisited in the future. 41 virtual int GetHeight() const = 0; 42 43 // Returns the baseline, or ascent, of the font. 44 virtual int GetBaseline() const = 0; 45 46 // Returns the cap height of the font. 47 virtual int GetCapHeight() const = 0; 48 49 // Returns the expected number of horizontal pixels needed to display the 50 // specified length of characters. Call GetStringWidth() to retrieve the 51 // actual number. 52 virtual int GetExpectedTextWidth(int length) const = 0; 53 54 // Returns the style of the font. 55 virtual int GetStyle() const = 0; 56 57 // Returns the specified font name in UTF-8. 58 virtual std::string GetFontName() const = 0; 59 60 // Returns the actually used font name in UTF-8. 61 virtual std::string GetActualFontNameForTesting() const = 0; 62 63 // Returns the font size in pixels. 64 virtual int GetFontSize() const = 0; 65 66 // Returns an object describing how the font should be rendered. 67 virtual const FontRenderParams& GetFontRenderParams() const = 0; 68 69 // Returns the native font handle. 70 virtual NativeFont GetNativeFont() const = 0; 71 72 protected: 73 virtual ~PlatformFont() {} 74 75 private: 76 friend class base::RefCounted<PlatformFont>; 77 }; 78 79 } // namespace gfx 80 81 #endif // UI_GFX_PLATFORM_FONT_H_ 82
