public void PolygonRegular()
{
var polygon = Shaper.PolygonRegular(new Vector3(10.0, 11.0), 10, 6);
Assert.Equal(6.0, polygon.Vertices.Count());
Assert.Equal(10.0, polygon.Centroid.X, 10);
Assert.Equal(11.0, polygon.Centroid.Y, 10);
}