static d.PointF AddToPath(this PolyLineSegment segment, d.PointF startPoint, d2.GraphicsPath path) {
d.PointF[] points = new d.PointF[segment.Points.Count + 1];
var i = 0;
points[i++] = startPoint;
foreach(var p in segment.Points) points[i++] = p.ToGdiPlus();
path.AddLines(points);
return points[i - 1];
}
