| output | Reference to the NativeArray to write the data into. The NativeArray or underlying memory cannot be Disposed until the request is complete. |
| src | The Texture resource to read the data from. |
| mipIndex | The index of the mipmap to fetch. |
| dstFormat | The target TextureFormat of the data. Conversion happens automatically if this format is different from the format stored on the GPU. |
| x | The starting x-coordinate, in pixels, of the Texture data to fetch. |
| width | The width, in pixels, of the Texture data to fetch. |
| y | The starting y-coordinate, in pixels, of the Texture data to fetch. |
| height | The height, in pixels, of the Texture data to fetch. |
| z | The starting z-coordinate, in pixels, of the Texture3D to fetch. For TextureCube, Texture2DArray, and TextureCubeArray, this is the index of the start layer. |
| depth | The depth, in pixels of the Texture3D to fetch. For TextureCube, Texture2DArray, and TextureCubeArray, this is the number of layers to retrieve. |
| callback | An optional delegate System.Action to call after Unity completes the request. When Unity calls the delegate, it passes the completed request as a parameter to the System.Action. |
AsyncGPUReadbackRequest Returns an AsyncGPUReadbackRequest that you can use to determine when the data is available. Otherwise, returns a request with an error.
Retrieves data asynchronously from a GPU Texture resource.
If the return value is a request with an error, calling AsyncGPUReadbackRequest.hasError returns true.
对于纹理数据，将根据源纹理的尺寸检查范围。如果图形 QualitySettings 设置得足够低而足以生成缩小尺寸的纹理，则必须请求缩小的尺寸。使用 QualitySettings.masterTextureLimit 通过向右移位的方式调整宽度和高度（以及 x、y，如果需要的话）。
For texture data, use the SystemInfo.IsFormatSupported method with the GraphicsFormatUsage.ReadPixels flag to query if the format is supported.
| output | Reference to the NativeArray to write the data into. The NativeArray or underlying memory cannot be Disposed until the request is complete. |
| src | The GraphicsBuffer to read the data from. |
| size | The size, in bytes, of the data to retrieve from the GraphicsBuffer. |
| offset | Offset in bytes in the GraphicsBuffer. |
| callback | An optional delegate System.Action to call after Unity completes the request. When Unity calls the delegate, it passes the completed request as a parameter to the System.Action. |
AsyncGPUReadbackRequest Returns an AsyncGPUReadbackRequest that you can use to determine when the data is available. Otherwise, returns a request with an error.
Retrieves data asynchronously from a GPU Graphics Buffer resource.
If the return value is a request with an error, calling AsyncGPUReadbackRequest.hasError returns true.
对于纹理数据，将根据源纹理的尺寸检查范围。如果图形 QualitySettings 设置得足够低而足以生成缩小尺寸的纹理，则必须请求缩小的尺寸。使用 QualitySettings.masterTextureLimit 通过向右移位的方式调整宽度和高度（以及 x、y，如果需要的话）。
For texture data, use the SystemInfo.IsFormatSupported method with the GraphicsFormatUsage.ReadPixels flag to query if the format is supported.