lib/ui/painting/multi_frame_codec.h

// 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_LIB_UI_PAINTING_MUTLI_FRAME_CODEC_H_
#define FLUTTER_LIB_UI_PAINTING_MUTLI_FRAME_CODEC_H_

#include "flutter/fml/macros.h"
#include "flutter/lib/ui/painting/codec.h"

namespace flutter {

class MultiFrameCodec : public Codec {
 public:
  MultiFrameCodec(std::unique_ptr<SkCodec> codec);

  ~MultiFrameCodec() override;

  // |Codec|
  int frameCount() const override;

  // |Codec|
  int repetitionCount() const override;

  // |Codec|
  Dart_Handle getNextFrame(Dart_Handle args) override;

 private:
  const std::unique_ptr<SkCodec> codec_;
  const int frameCount_;
  const int repetitionCount_;
  int nextFrameIndex_;

  // The last decoded frame that's required to decode any subsequent frames.
  std::unique_ptr<SkBitmap> lastRequiredFrame_;
  // The index of the last decoded required frame.
  int lastRequiredFrameIndex_ = -1;

  sk_sp<SkImage> GetNextFrameImage(fml::WeakPtr<GrContext> resourceContext);

  void GetNextFrameAndInvokeCallback(
      std::unique_ptr<DartPersistentValue> callback,
      fml::RefPtr<fml::TaskRunner> ui_task_runner,
      fml::WeakPtr<GrContext> resourceContext,
      fml::RefPtr<flutter::SkiaUnrefQueue> unref_queue,
      size_t trace_id);

  FML_FRIEND_MAKE_REF_COUNTED(MultiFrameCodec);
  FML_FRIEND_REF_COUNTED_THREAD_SAFE(MultiFrameCodec);
};

}  // namespace flutter

#endif  // FLUTTER_LIB_UI_PAINTING_MUTLI_FRAME_CODEC_H_