flutter::ImageEncodingImpeller Class Reference

#include <image_encoding_impeller.h>

Static Public Member Functions
static int	GetColorSpace (const std::shared_ptr< impeller::Texture > &texture)
static void	ConvertDlImageToSkImage (const sk_sp< DlImage > &dl_image, std::function< void(fml::StatusOr< sk_sp< SkImage > >)> encode_task, const std::shared_ptr< impeller::Context > &impeller_context)
static void	ConvertImageToRaster (const sk_sp< DlImage > &dl_image, std::function< void(fml::StatusOr< sk_sp< SkImage > >)> encode_task, const fml::RefPtr< fml::TaskRunner > &raster_task_runner, const fml::RefPtr< fml::TaskRunner > &io_task_runner, const std::shared_ptr< const fml::SyncSwitch > &is_gpu_disabled_sync_switch, const std::shared_ptr< impeller::Context > &impeller_context)

Detailed Description

Definition at line 19 of file image_encoding_impeller.h.

Member Function Documentation

ConvertDlImageToSkImage()

void flutter::ImageEncodingImpeller::ConvertDlImageToSkImage ( const sk_sp< DlImage > &  dl_image, std::function< void(fml::StatusOr< sk_sp< SkImage > >)>  encode_task, const std::shared_ptr< impeller::Context > &  impeller_context  )

static

Converts a DlImage to a SkImage. This should be called from the thread that corresponds to dl_image->owning_context() when gpu access is guaranteed. See also: ConvertImageToRaster. Visible for testing.

Definition at line 124 of file image_encoding_impeller.cc.

                                                            {
  auto texture = dl_image->impeller_texture();
 
  if (impeller_context == nullptr) {
    encode_task(fml::Status(fml::StatusCode::kFailedPrecondition,
                            "Impeller context was null."));
    return;
  }
 
  if (texture == nullptr) {
    encode_task(
        fml::Status(fml::StatusCode::kFailedPrecondition, "Image was null."));
    return;
  }
 
  auto dimensions = dl_image->dimensions();
  auto color_type = ToSkColorType(texture->GetTextureDescriptor().format);
 
  if (dimensions.isEmpty()) {
    encode_task(fml::Status(fml::StatusCode::kFailedPrecondition,
                            "Image dimensions were empty."));
    return;
  }
 
  if (!color_type.has_value()) {
    encode_task(fml::Status(fml::StatusCode::kUnimplemented,
                            "Failed to get color type from pixel format."));
    return;
  }
 
  impeller::DeviceBufferDescriptor buffer_desc;
  buffer_desc.storage_mode = impeller::StorageMode::kHostVisible;
  buffer_desc.readback = true;  // set to false for testing.
  buffer_desc.size =
      texture->GetTextureDescriptor().GetByteSizeOfBaseMipLevel();
  auto buffer =
      impeller_context->GetResourceAllocator()->CreateBuffer(buffer_desc);
  auto command_buffer = impeller_context->CreateCommandBuffer();
  command_buffer->SetLabel("BlitTextureToBuffer Command Buffer");
  auto pass = command_buffer->CreateBlitPass();
  pass->SetLabel("BlitTextureToBuffer Blit Pass");
  pass->AddCopy(texture, buffer);
  pass->EncodeCommands(impeller_context->GetResourceAllocator());
  auto completion = [buffer, color_type = color_type.value(), dimensions,
                     encode_task = std::move(encode_task)](
                        impeller::CommandBuffer::Status status) {
    if (status != impeller::CommandBuffer::Status::kCompleted) {
      encode_task(fml::Status(fml::StatusCode::kUnknown, ""));
      return;
    }
    buffer->Invalidate();
    auto sk_image = ConvertBufferToSkImage(buffer, color_type, dimensions);
    encode_task(sk_image);
  };
 
  if (!impeller_context->GetCommandQueue()
           ->Submit({command_buffer}, completion)
           .ok()) {
    FML_LOG(ERROR) << "Failed to submit commands.";
  }
}

ConvertImageToRaster()

void flutter::ImageEncodingImpeller::ConvertImageToRaster ( const sk_sp< DlImage > &  dl_image, std::function< void(fml::StatusOr< sk_sp< SkImage > >)>  encode_task, const fml::RefPtr< fml::TaskRunner > &  raster_task_runner, const fml::RefPtr< fml::TaskRunner > &  io_task_runner, const std::shared_ptr< const fml::SyncSwitch > &  is_gpu_disabled_sync_switch, const std::shared_ptr< impeller::Context > &  impeller_context  )

static

Converts a DlImage to a SkImage. encode_task is executed with the resulting SkImage.

Definition at line 189 of file image_encoding_impeller.cc.

                                                            {
  auto original_encode_task = std::move(encode_task);
  encode_task = [original_encode_task = std::move(original_encode_task),
                 io_task_runner](fml::StatusOr<sk_sp<SkImage>> image) mutable {
    fml::TaskRunner::RunNowOrPostTask(
        io_task_runner,
        [original_encode_task = std::move(original_encode_task),
         image = std::move(image)]() { original_encode_task(image); });
  };
 
  if (dl_image->owning_context() != DlImage::OwningContext::kRaster) {
    DoConvertImageToRasterImpellerWithRetry(dl_image, std::move(encode_task),
                                            is_gpu_disabled_sync_switch,
                                            impeller_context,
                                            /*retry_runner=*/nullptr);
    return;
  }
 
  raster_task_runner->PostTask([dl_image, encode_task = std::move(encode_task),
                                io_task_runner, is_gpu_disabled_sync_switch,
                                impeller_context,
                                raster_task_runner]() mutable {
    DoConvertImageToRasterImpellerWithRetry(
        dl_image, std::move(encode_task), is_gpu_disabled_sync_switch,
        impeller_context, raster_task_runner);
  });
}

GetColorSpace()

int flutter::ImageEncodingImpeller::GetColorSpace ( const std::shared_ptr< impeller::Texture > &  texture )

static

Definition at line 223 of file image_encoding_impeller.cc.

                                                   {
  const impeller::TextureDescriptor& desc = texture->GetTextureDescriptor();
  switch (desc.format) {
    case impeller::PixelFormat::kB10G10R10XR:  // intentional_fallthrough
    case impeller::PixelFormat::kR16G16B16A16Float:
      return ColorSpace::kExtendedSRGB;
    default:
      return ColorSpace::kSRGB;
  }
}

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The documentation for this class was generated from the following files:

• lib/ui/painting/image_encoding_impeller.h
• lib/ui/painting/image_encoding_impeller.cc