ui/gfx/platform_font_linux.h

   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_LINUX_H_
   6 #define UI_GFX_PLATFORM_FONT_LINUX_H_
   7
   8 #include <string>
   9
  10 #include "base/compiler_specific.h"
  11 #include "base/memory/scoped_ptr.h"
  12 #include "skia/ext/refptr.h"
  13 #include "third_party/skia/include/core/SkRefCnt.h"
  14 #include "ui/gfx/font_render_params.h"
  15 #include "ui/gfx/platform_font.h"
  16
  17 class SkTypeface;
  18 class SkPaint;
  19
  20 namespace gfx {
  21
  22 class GFX_EXPORT PlatformFontLinux : public PlatformFont {
  23  public:
  24   // TODO(derat): Get rid of the default constructor in favor of using
  25   // gfx::FontList (which also has the concept of a default font but may contain
  26   // multiple font families) everywhere. See http://crbug.com/398885#c16.
  27   PlatformFontLinux();
  28   PlatformFontLinux(const std::string& font_name, int font_size_pixels);
  29
  30   // Resets and reloads the cached system font used by the default constructor.
  31   // This function is useful when the system font has changed, for example, when
  32   // the locale has changed.
  33   static void ReloadDefaultFont();
  34
  35 #if defined(OS_CHROMEOS)
  36   // Sets the default font. |font_description| is a gfx::FontList font
  37   // description; only the first family will be used.
  38   static void SetDefaultFontDescription(const std::string& font_description);
  39 #endif
  40
  41   // Overridden from PlatformFont:
  42   Font DeriveFont(int size_delta, int style) const override;
  43   int GetHeight() const override;
  44   int GetBaseline() const override;
  45   int GetCapHeight() const override;
  46   int GetExpectedTextWidth(int length) const override;
  47   int GetStyle() const override;
  48   std::string GetFontName() const override;
  49   std::string GetActualFontNameForTesting() const override;
  50   int GetFontSize() const override;
  51   const FontRenderParams& GetFontRenderParams() override;
  52
  53  private:
  54   // Create a new instance of this object with the specified properties. Called
  55   // from DeriveFont.
  56   PlatformFontLinux(const skia::RefPtr<SkTypeface>& typeface,
  57                     const std::string& family,
  58                     int size_pixels,
  59                     int style,
  60                     const FontRenderParams& params);
  61   ~PlatformFontLinux() override;
  62
  63   // Initializes this object based on the passed-in details. If |typeface| is
  64   // empty, a new typeface will be loaded.
  65   void InitFromDetails(
  66       const skia::RefPtr<SkTypeface>& typeface,
  67       const std::string& font_family,
  68       int font_size_pixels,
  69       int style,
  70       const FontRenderParams& params);
  71
  72   // Initializes this object as a copy of another PlatformFontLinux.
  73   void InitFromPlatformFont(const PlatformFontLinux* other);
  74
  75   skia::RefPtr<SkTypeface> typeface_;
  76
  77   // Additional information about the face.
  78   // Skia actually expects a family name and not a font name.
  79   std::string font_family_;
  80   int font_size_pixels_;
  81   int style_;
  82 #if defined(OS_CHROMEOS)
  83   float device_scale_factor_;
  84 #endif
  85
  86   // Information describing how the font should be rendered.
  87   FontRenderParams font_render_params_;
  88
  89   // Cached metrics, generated at construction.
  90   int ascent_pixels_;
  91   int height_pixels_;
  92   int cap_height_pixels_;
  93   double average_width_pixels_;
  94
  95 #if defined(OS_CHROMEOS)
  96   // A font description string of the format used by gfx::FontList.
  97   static std::string* default_font_description_;
  98 #endif
  99
 100   DISALLOW_COPY_AND_ASSIGN(PlatformFontLinux);
 101 };
 102
 103 }  // namespace gfx
 104
 105 #endif  // UI_GFX_PLATFORM_FONT_LINUX_H_