ui/gfx/linux_font_delegate.h

   1 // Copyright 2013 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_LINUX_FONT_DELEGATE_H_
   6 #define UI_GFX_LINUX_FONT_DELEGATE_H_
   7
   8 #include <string>
   9
  10 #include "base/memory/scoped_ptr.h"
  11 #include "ui/gfx/font_render_params.h"
  12 #include "ui/gfx/gfx_export.h"
  13
  14 namespace gfx {
  15
  16 class ScopedPangoFontDescription;
  17
  18 // Allows a Linux platform-specific overriding of font preferences.
  19 class GFX_EXPORT LinuxFontDelegate {
  20  public:
  21   virtual ~LinuxFontDelegate() {}
  22
  23   // Sets the dynamically loaded singleton that provides font preferences.
  24   // This pointer is not owned, and if this method is called a second time,
  25   // the first instance is not deleted.
  26   static void SetInstance(LinuxFontDelegate* instance);
  27
  28   // Returns a LinuxFontDelegate instance for the toolkit used in
  29   // the user's desktop environment.
  30   //
  31   // Can return NULL, in case no toolkit has been set. (For example, if we're
  32   // running with the "--ash" flag.)
  33   static const LinuxFontDelegate* instance();
  34
  35   // Returns the default font rendering settings.
  36   virtual FontRenderParams GetDefaultFontRenderParams() const = 0;
  37
  38   // Returns the Pango description for the default UI font.
  39   virtual scoped_ptr<ScopedPangoFontDescription>
  40       GetDefaultPangoFontDescription() const = 0;
  41
  42   // Returns the resolution (as pixels-per-inch) that should be used to convert
  43   // font sizes between points and pixels. -1 is returned if the DPI is unset.
  44   virtual double GetFontDPI() const = 0;
  45 };
  46
  47 }  // namespace gfx
  48
  49 #endif  // UI_GFX_LINUX_FONT_DELEGATE_H_