private void Update(float updatePeriod)
{
//timeSec += e.Time;
//var seconds = (float)timeSec;
var seconds = (float)timeSource.Elapsed.TotalSeconds;
var activeSegment = CatmullRomSpline.FindSegment(seconds, wayPoints.Count);
var pos = CatmullRomSpline.EvaluateSegment(wayPoints[activeSegment.Item1]
, wayPoints[activeSegment.Item2]
, wayTangents[activeSegment.Item1]
, wayTangents[activeSegment.Item2]
, seconds - (float)Math.Floor(seconds));
bird.CenterX = pos.X;
bird.CenterY = pos.Y;
}