void Start()
{
_of = GetComponent<OpticalFlowWorker>();
_tex = new Texture2D(0, 0, TextureFormat.RGB24, false);
var mf = flow.GetComponent<MeshFilter>();
_mesh = mf.mesh = new Mesh();
background.renderer.sharedMaterial.mainTexture = _tex;
_corners0 = FlowUtil.GenGridCorners(_of.width, _of.height, 50f);
_result = _of.CalculateOpticalFlow(_corners0);
}