lazy_glyph_atlas.h

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// 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_TYPOGRAPHER_LAZY_GLYPH_ATLAS_H_
#define FLUTTER_IMPELLER_TYPOGRAPHER_LAZY_GLYPH_ATLAS_H_
 
#include "impeller/geometry/rational.h"
#include "impeller/renderer/context.h"
#include "impeller/typographer/glyph_atlas.h"
#include "impeller/typographer/text_frame.h"
#include "impeller/typographer/typographer_context.h"
 
namespace impeller {
 
class LazyGlyphAtlas {
 public:
  explicit LazyGlyphAtlas(
      std::shared_ptr<TypographerContext> typographer_context);
 
  ~LazyGlyphAtlas();
 
  void AddTextFrame(const std::shared_ptr<TextFrame>& frame,
                    Rational scale,
                    Point offset,
                    const Matrix& transform,
                    std::optional<GlyphProperties> properties);
 
  void ResetTextFrames();
 
  const std::shared_ptr<GlyphAtlas>& CreateOrGetGlyphAtlas(
      Context& context,
      HostBuffer& host_buffer,
      GlyphAtlas::Type type) const;
 
 private:
  std::shared_ptr<TypographerContext> typographer_context_;
 
  std::vector<std::shared_ptr<TextFrame>> alpha_text_frames_;
  std::vector<std::shared_ptr<TextFrame>> color_text_frames_;
  std::shared_ptr<GlyphAtlasContext> alpha_context_;
  std::shared_ptr<GlyphAtlasContext> color_context_;
  mutable std::shared_ptr<GlyphAtlas> alpha_atlas_;
  mutable std::shared_ptr<GlyphAtlas> color_atlas_;
 
  LazyGlyphAtlas(const LazyGlyphAtlas&) = delete;
 
  LazyGlyphAtlas& operator=(const LazyGlyphAtlas&) = delete;
};
 
}  // namespace impeller
 
#endif  // FLUTTER_IMPELLER_TYPOGRAPHER_LAZY_GLYPH_ATLAS_H_