private Task OnAnchorData(MessageContainer container)
        {
            MessageWorldAnchor message = MessageWorldAnchor.Unpack(container);

            Debug.Log("Anchor data arrived.");
            anchorData = message.AnchorData;
            Debug.Log(anchorData.Length);
            IsDownloadingAnchor = false;
            gotOne = true;
            return(Task.CompletedTask);
        }