ui/gfx/font_render_params.h

   1 // Copyright 2014 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_FONT_RENDER_PARAMS_H_
   6 #define UI_GFX_FONT_RENDER_PARAMS_H_
   7
   8 #include <string>
   9 #include <vector>
  10
  11 #include "ui/gfx/gfx_export.h"
  12
  13 namespace gfx {
  14
  15 // A collection of parameters describing how text should be rendered on Linux.
  16 struct GFX_EXPORT FontRenderParams {
  17   FontRenderParams();
  18   ~FontRenderParams();
  19
  20   // Level of hinting to be applied.
  21   enum Hinting {
  22     HINTING_NONE = 0,
  23     HINTING_SLIGHT,
  24     HINTING_MEDIUM,
  25     HINTING_FULL,
  26   };
  27
  28   // Different subpixel orders to be used for subpixel rendering.
  29   enum SubpixelRendering {
  30     SUBPIXEL_RENDERING_NONE = 0,
  31     SUBPIXEL_RENDERING_RGB,
  32     SUBPIXEL_RENDERING_BGR,
  33     SUBPIXEL_RENDERING_VRGB,
  34     SUBPIXEL_RENDERING_VBGR,
  35   };
  36
  37   // Antialiasing (grayscale if |subpixel_rendering| is SUBPIXEL_RENDERING_NONE
  38   // and RGBA otherwise).
  39   bool antialiasing;
  40
  41   // Should subpixel positioning (i.e. fractional X positions for glyphs) be
  42   // used?
  43   bool subpixel_positioning;
  44
  45   // Should FreeType's autohinter be used (as opposed to Freetype's bytecode
  46   // interpreter, which uses fonts' own hinting instructions)?
  47   bool autohinter;
  48
  49   // Should embedded bitmaps in fonts should be used?
  50   bool use_bitmaps;
  51
  52   // Hinting level.
  53   Hinting hinting;
  54
  55   // Whether subpixel rendering should be used or not, and if so, the display's
  56   // subpixel order.
  57   SubpixelRendering subpixel_rendering;
  58 };
  59
  60 // Returns the system's default parameters for font rendering.
  61 GFX_EXPORT const FontRenderParams& GetDefaultFontRenderParams();
  62
  63 // Returns the system's default parameters for WebKit font rendering.
  64 // TODO(derat): Rename to GetDefaultFontRenderParamsForWebContents().
  65 GFX_EXPORT const FontRenderParams& GetDefaultWebKitFontRenderParams();
  66
  67 // Returns the appropriate parameters for rendering the font described by the
  68 // passed-in-arguments, any of which may be NULL. If |family_out| is non-NULL,
  69 // it will be updated to contain the recommended font family from |family_list|.
  70 // TODO(derat): Also accept the font style, so that its bold and italic states
  71 // can be passed to Fontconfig in the Linux implementation.
  72 GFX_EXPORT FontRenderParams GetCustomFontRenderParams(
  73     bool for_web_contents,
  74     const std::vector<std::string>* family_list,
  75     const int* pixel_size,
  76     const int* point_size,
  77     std::string* family_out);
  78
  79 }  // namespace gfx
  80
  81 #endif  // UI_GFX_FONT_RENDER_PARAMS_H_