protected virtual void DrawCenter(HandData hand, DrawingContext drawingContext)
{
drawingContext.DrawEllipse(Brushes.Blue, null, new System.Windows.Point(hand.Location.X, hand.Location.Y), 5, 5);
if (hand.HasPalmPoint)
{
drawingContext.DrawEllipse(Brushes.SpringGreen, null, new System.Windows.Point(hand.PalmPoint.Value.X, hand.PalmPoint.Value.Y), 5, 5);
var palmSize = hand.PalmDistance;
drawingContext.DrawEllipse(null, this.greenPen, new System.Windows.Point(hand.PalmPoint.Value.X, hand.PalmPoint.Value.Y), palmSize, palmSize);
}
}