gecko-dev/gfx/thebes/gfxFontMissingGlyphs.h

/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef GFX_FONTMISSINGGLYPHS_H
#define GFX_FONTMISSINGGLYPHS_H

#include "mozilla/Attributes.h"
#include "mozilla/gfx/MatrixFwd.h"
#include "mozilla/gfx/Rect.h"

namespace mozilla {
namespace gfx {
class DrawTarget;
class Pattern;
}  // namespace gfx
}  // namespace mozilla

/**
 * This class should not be instantiated. It's just a container
 * for some helper functions.
 */
class gfxFontMissingGlyphs final {
  typedef mozilla::gfx::DrawTarget DrawTarget;
  typedef mozilla::gfx::Float Float;
  typedef mozilla::gfx::Matrix Matrix;
  typedef mozilla::gfx::Pattern Pattern;
  typedef mozilla::gfx::Rect Rect;

  gfxFontMissingGlyphs() = delete;  // prevent instantiation

 public:
  /**
   * Draw hexboxes for a missing glyph.
   * @param aChar the UTF16 codepoint for the character
   * @param aRect the glyph-box for the glyph that is missing
   * @param aDrawTarget the DrawTarget to draw to
   * @param aPattern the pattern currently being used to paint
   * @param aAppUnitsPerDevPixel the appUnits to devPixel ratio we're using,
   *                             (so we can scale glyphs to a sensible size)
   * @param aMat optional local-space orientation matrix
   */
  static void DrawMissingGlyph(uint32_t aChar, const Rect& aRect,
                               DrawTarget& aDrawTarget, const Pattern& aPattern,
                               uint32_t aAppUnitsPerDevPixel,
                               const Matrix* aMat = nullptr);
  /**
   * @return the desired minimum width for a glyph-box that will allow
   * the hexboxes to be drawn reasonably.
   */
  static Float GetDesiredMinWidth(uint32_t aChar, uint32_t aAppUnitsPerDevUnit);

  static void Purge();

  static void Shutdown();
};

#endif