pixel_deferred_image_gpu_impeller.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_LIB_UI_PAINTING_PIXEL_DEFERRED_IMAGE_GPU_IMPELLER_H_
#define FLUTTER_LIB_UI_PAINTING_PIXEL_DEFERRED_IMAGE_GPU_IMPELLER_H_
 
#include <memory>
#include <mutex>
#include <optional>
#include <string>
 
#include "flutter/display_list/image/dl_image.h"
#include "flutter/fml/memory/weak_ptr.h"
#include "flutter/fml/task_runner.h"
#include "flutter/lib/ui/snapshot_delegate.h"
#include "impeller/core/texture.h"
#include "impeller/display_list/dl_image_impeller.h"
#include "third_party/skia/include/core/SkImage.h"
 
namespace flutter {
 
/// A deferred image that is created from pixels.
/// @see DisplayListDeferredImageGPUImpeller for another example of a deferred
/// image.
/// @see dart:ui `decodeImageFromPixelsSync` for the user of this class.
class PixelDeferredImageGPUImpeller final : public impeller::DlImageImpeller {
 public:
  static sk_sp<PixelDeferredImageGPUImpeller> Make(
      sk_sp<SkImage> image,
      fml::TaskRunnerAffineWeakPtr<SnapshotDelegate> snapshot_delegate,
      fml::RefPtr<fml::TaskRunner> raster_task_runner);
 
  // |DlImage|
  ~PixelDeferredImageGPUImpeller() override;
 
  // |DlImageImpeller|
  std::shared_ptr<impeller::Texture> GetImpellerTexture(
      const std::shared_ptr<impeller::Context>& context) const override;
 
  // |DlImage|
  bool isOpaque() const override;
 
  // |DlImage|
  bool isUIThreadSafe() const override;
 
  // |DlImage|
  DlISize GetSize() const override;
 
  // |DlImage|
  size_t GetApproximateByteSize() const override;
 
  // |DlImage|
  DlColorSpace GetColorSpace() const override;
 
  // |DlImage|
  std::optional<std::string> get_error() const override;
 
 private:
  class ImageWrapper : public std::enable_shared_from_this<ImageWrapper> {
   public:
    static std::shared_ptr<ImageWrapper> Make(
        sk_sp<SkImage> image,
        fml::TaskRunnerAffineWeakPtr<SnapshotDelegate> snapshot_delegate,
        fml::RefPtr<fml::TaskRunner> raster_task_runner);
 
    ImageWrapper(
        const sk_sp<SkImage>& image,
        fml::TaskRunnerAffineWeakPtr<SnapshotDelegate> snapshot_delegate,
        fml::RefPtr<fml::TaskRunner> raster_task_runner);
 
    ~ImageWrapper();
 
    std::shared_ptr<impeller::Texture> texture() const { return texture_; }
 
    const DlISize& size() const { return size_; }
 
    std::optional<std::string> get_error() const;
 
   private:
    void SnapshotImage(sk_sp<SkImage> image);
 
    DlISize size_;
    fml::TaskRunnerAffineWeakPtr<SnapshotDelegate> snapshot_delegate_;
    fml::RefPtr<fml::TaskRunner> raster_task_runner_;
    std::shared_ptr<impeller::Texture> texture_;
    mutable std::mutex error_mutex_;
    std::optional<std::string> error_;
 
    FML_DISALLOW_COPY_AND_ASSIGN(ImageWrapper);
  };
 
  explicit PixelDeferredImageGPUImpeller(std::shared_ptr<ImageWrapper> wrapper);
 
  std::shared_ptr<ImageWrapper> wrapper_;
 
  FML_DISALLOW_COPY_AND_ASSIGN(PixelDeferredImageGPUImpeller);
};
 
}  // namespace flutter
 
#endif  // FLUTTER_LIB_UI_PAINTING_PIXEL_DEFERRED_IMAGE_GPU_IMPELLER_H_