chromium/src/third_party/blink/renderer/core/layout/layout_text_combine.h

/*
 * Copyright (C) 2011 Apple Inc. All rights reserved.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 *
 */

#ifndef THIRD_PARTY_BLINK_RENDERER_CORE_LAYOUT_LAYOUT_TEXT_COMBINE_H_
#define THIRD_PARTY_BLINK_RENDERER_CORE_LAYOUT_LAYOUT_TEXT_COMBINE_H_

#include "third_party/blink/renderer/core/layout/layout_text.h"
#include "third_party/blink/renderer/platform/fonts/font.h"

namespace blink {

class GraphicsContext;

// LayoutTextCombine uses different coordinate systems for layout and
// inlineTextBox, because it is treated as 1em-box character in vertical flow
// for the layout, while its inline box is in horizontal flow.
class LayoutTextCombine final : public LayoutText {
 public:
  LayoutTextCombine(Node*, scoped_refptr<StringImpl>);

  bool IsCombined() const {
    NOT_DESTROYED();
    return is_combined_;
  }
  float CombinedTextWidth(const Font& font) const {
    NOT_DESTROYED();
    return font.GetFontDescription().ComputedSize();
  }
  const Font& OriginalFont() const {
    NOT_DESTROYED();
    return Parent()->StyleRef().GetFont();
  }
  void TransformToInlineCoordinates(GraphicsContext&,
                                    const PhysicalRect& box_rect,
                                    bool clip = false) const;
  LayoutUnit InlineWidthForLayout() const;

  const char* GetName() const override {
    NOT_DESTROYED();
    return "LayoutTextCombine";
  }

 private:
  bool IsCombineText() const override {
    NOT_DESTROYED();
    return true;
  }
  float Width(unsigned from,
              unsigned length,
              const Font&,
              LayoutUnit x_position,
              TextDirection,
              HashSet<const SimpleFontData*>* fallback_fonts = nullptr,
              FloatRect* glyph_bounds = nullptr,
              float expansion = 0) const override;
  void StyleDidChange(StyleDifference, const ComputedStyle* old_style) override;
  void TextDidChange() override;
  void UpdateIsCombined();
  void UpdateFontStyleForCombinedText();

  float combined_text_width_;
  float scale_x_;
  bool is_combined_ : 1;
};

template <>
struct DowncastTraits<LayoutTextCombine> {
  static bool AllowFrom(const LayoutObject& object) {
    return object.IsCombineText();
  }
};

inline LayoutUnit LayoutTextCombine::InlineWidthForLayout() const {
  return LayoutUnit::FromFloatCeil(combined_text_width_);
}

}  // namespace blink

#endif  // THIRD_PARTY_BLINK_RENDERER_CORE_LAYOUT_LAYOUT_TEXT_COMBINE_H_