unity 调用摄像头

 WebCamTexture webcamTexture = new WebCamTexture();

        //如果有后置摄像头，调用后置摄像头  
        for (int i = 0; i < WebCamTexture.devices.Length; i++)
        {
            if (!WebCamTexture.devices[i].isFrontFacing)
            {
                webcamTexture.deviceName = WebCamTexture.devices[i].name;
                break;
            }
        }

        Renderer renderer = GetComponent<Renderer>();
        renderer.material.mainTexture = webcamTexture;
        webcamTexture.Play(); WebCamTexture webcamTexture = new WebCamTextur