text_contents.h

Go to the documentation of this file.

// Copyright 2013 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
 
#ifndef FLUTTER_IMPELLER_ENTITY_CONTENTS_TEXT_CONTENTS_H_
#define FLUTTER_IMPELLER_ENTITY_CONTENTS_TEXT_CONTENTS_H_
 
#include <functional>
#include <memory>
#include <variant>
#include <vector>
 
#include "flutter/fml/macros.h"
#include "impeller/entity/contents/contents.h"
#include "impeller/geometry/color.h"
#include "impeller/typographer/glyph_atlas.h"
#include "impeller/typographer/text_frame.h"
 
namespace impeller {
 
class LazyGlyphAtlas;
class Context;
 
class TextContents final : public Contents {
 public:
  TextContents();
 
  ~TextContents();
 
  void SetTextFrame(const std::shared_ptr<TextFrame>& frame);
 
  void SetColor(Color color);
 
  /// @brief Force the text color to apply to the rendered glyphs, even if those
  ///        glyphs are bitmaps.
  ///
  ///        This is used to ensure that mask blurs work correctly on emoji.
  void SetForceTextColor(bool value);
 
  Color GetColor() const;
 
  // |Contents|
  bool CanInheritOpacity(const Entity& entity) const override;
 
  // |Contents|
  void SetInheritedOpacity(Scalar opacity) override;
 
  void SetOffset(Vector2 offset);
 
  std::optional<Rect> GetTextFrameBounds() const;
 
  // |Contents|
  std::optional<Rect> GetCoverage(const Entity& entity) const override;
 
  // |Contents|
  void PopulateGlyphAtlas(
      const std::shared_ptr<LazyGlyphAtlas>& lazy_glyph_atlas,
      Scalar scale) override;
 
  // |Contents|
  bool Render(const ContentContext& renderer,
              const Entity& entity,
              RenderPass& pass) const override;
 
 private:
  std::shared_ptr<TextFrame> frame_;
  Scalar scale_ = 1.0;
  Color color_;
  Scalar inherited_opacity_ = 1.0;
  Vector2 offset_;
  bool force_text_color_ = false;
 
  std::shared_ptr<GlyphAtlas> ResolveAtlas(
      Context& context,
      GlyphAtlas::Type type,
      const std::shared_ptr<LazyGlyphAtlas>& lazy_atlas) const;
 
  TextContents(const TextContents&) = delete;
 
  TextContents& operator=(const TextContents&) = delete;
};
 
}  // namespace impeller
 
#endif  // FLUTTER_IMPELLER_ENTITY_CONTENTS_TEXT_CONTENTS_H_