third_party/blink/public/platform/web_font_render_style.h

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#ifndef THIRD_PARTY_BLINK_PUBLIC_PLATFORM_WEB_FONT_RENDER_STYLE_H_
#define THIRD_PARTY_BLINK_PUBLIC_PLATFORM_WEB_FONT_RENDER_STYLE_H_

#include "SkFontStyle.h"
#include "SkPaint.h"
#include "third_party/blink/public/platform/web_string.h"
#include "third_party/skia/include/core/SkRefCnt.h"

class SkFont;
class SkFontMgr;

namespace blink {

// WebFontRenderStyle describes the user's preferences for rendering a font at a
// given size.
struct WebFontRenderStyle {
  enum {
    kNoPreference = 2,
  };

  WebFontRenderStyle() = default;

  bool operator==(const WebFontRenderStyle& a) const {
    return use_bitmaps == a.use_bitmaps && use_auto_hint == a.use_auto_hint &&
           use_hinting == a.use_hinting && hint_style == a.hint_style &&
           use_anti_alias == a.use_anti_alias &&
           use_subpixel_rendering == a.use_subpixel_rendering &&
           use_subpixel_positioning == a.use_subpixel_positioning;
  }

  BLINK_PLATFORM_EXPORT static void SetSkiaFontManager(sk_sp<SkFontMgr>);
  BLINK_PLATFORM_EXPORT static void SetHinting(SkPaint::Hinting);
  BLINK_PLATFORM_EXPORT static void SetAutoHint(bool);
  BLINK_PLATFORM_EXPORT static void SetUseBitmaps(bool);
  BLINK_PLATFORM_EXPORT static void SetAntiAlias(bool);
  BLINK_PLATFORM_EXPORT static void SetSubpixelRendering(bool);
  BLINK_PLATFORM_EXPORT static void SetSubpixelPositioning(bool);
  BLINK_PLATFORM_EXPORT static void SetSystemFontFamily(const WebString& name);

  static WebFontRenderStyle GetDefault();

  // Overrides fields with those from |other|, except the fields that are set to
  // kNoPreference in |other|.
  void OverrideWith(const WebFontRenderStyle& other);

  void ApplyToSkPaint(SkPaint&, float device_scale_factor) const;
  void ApplyToSkFont(SkFont*, float device_scale_factor) const;

  // Each of the use* members below can take one of three values:
  //   0: off
  //   1: on
  //   NoPreference: no preference expressed
  char use_bitmaps = kNoPreference;    // use embedded bitmap strike if possible
  char use_auto_hint = kNoPreference;  // use 'auto' hinting (FreeType specific)
  char use_hinting = kNoPreference;    // hint glyphs to the pixel grid
  char hint_style = 0;                 // level of hinting, 0..3
  char use_anti_alias = kNoPreference;  // antialias glyph shapes
  // use subpixel rendering (partially-filled pixels)
  char use_subpixel_rendering = kNoPreference;
  // use subpixel positioning (fractional X positions for glyphs)
  char use_subpixel_positioning = kNoPreference;
};

}  // namespace blink

#endif  // THIRD_PARTY_BLINK_PUBLIC_PLATFORM_WEB_FONT_RENDER_STYLE_H_