ui/gfx/platform_font_pango.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_PANGO_H_
   6 #define UI_GFX_PLATFORM_FONT_PANGO_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 PlatformFontPango : public PlatformFont {
  23  public:
  24   PlatformFontPango();
  25   explicit PlatformFontPango(NativeFont native_font);
  26   PlatformFontPango(const std::string& font_name, int font_size_pixels);
  27
  28   // Converts |gfx_font| to a new pango font. Free the returned font with
  29   // pango_font_description_free().
  30   static PangoFontDescription* PangoFontFromGfxFont(const gfx::Font& gfx_font);
  31
  32   // Resets and reloads the cached system font used by the default constructor.
  33   // This function is useful when the system font has changed, for example, when
  34   // the locale has changed.
  35   static void ReloadDefaultFont();
  36
  37 #if defined(OS_CHROMEOS)
  38   // Sets the default font. |font_description| is a Pango font description that
  39   // will be passed to pango_font_description_from_string().
  40   static void SetDefaultFontDescription(const std::string& font_description);
  41 #endif
  42
  43   // Overridden from PlatformFont:
  44   Font DeriveFont(int size_delta, int style) const override;
  45   int GetHeight() const override;
  46   int GetBaseline() const override;
  47   int GetCapHeight() const override;
  48   int GetExpectedTextWidth(int length) const override;
  49   int GetStyle() const override;
  50   std::string GetFontName() const override;
  51   std::string GetActualFontNameForTesting() const override;
  52   int GetFontSize() const override;
  53   const FontRenderParams& GetFontRenderParams() override;
  54   NativeFont GetNativeFont() const override;
  55
  56  private:
  57   // Create a new instance of this object with the specified properties. Called
  58   // from DeriveFont.
  59   PlatformFontPango(const skia::RefPtr<SkTypeface>& typeface,
  60                     const std::string& name,
  61                     int size_pixels,
  62                     int style,
  63                     const FontRenderParams& params);
  64   ~PlatformFontPango() override;
  65
  66   // Initializes this object based on the passed-in details. If |typeface| is
  67   // empty, a new typeface will be loaded.
  68   void InitFromDetails(
  69       const skia::RefPtr<SkTypeface>& typeface,
  70       const std::string& font_family,
  71       int font_size_pixels,
  72       int style,
  73       const FontRenderParams& params);
  74
  75   // Initializes this object as a copy of another PlatformFontPango.
  76   void InitFromPlatformFont(const PlatformFontPango* other);
  77
  78   skia::RefPtr<SkTypeface> typeface_;
  79
  80   // Additional information about the face.
  81   // Skia actually expects a family name and not a font name.
  82   std::string font_family_;
  83   int font_size_pixels_;
  84   int style_;
  85 #if defined(OS_CHROMEOS)
  86   float device_scale_factor_;
  87 #endif
  88
  89   // Information describing how the font should be rendered.
  90   FontRenderParams font_render_params_;
  91
  92   // Cached metrics, generated at construction.
  93   int ascent_pixels_;
  94   int height_pixels_;
  95   int cap_height_pixels_;
  96   double average_width_pixels_;
  97
  98   // The default font, used for the default constructor.
  99   static Font* default_font_;
 100
 101 #if defined(OS_CHROMEOS)
 102   // A Pango font description.
 103   static std::string* default_font_description_;
 104 #endif
 105
 106   DISALLOW_COPY_AND_ASSIGN(PlatformFontPango);
 107 };
 108
 109 }  // namespace gfx
 110
 111 #endif  // UI_GFX_PLATFORM_FONT_PANGO_H_