/// The control points to our curve.
    points: Vec<Vec3>,
    /// The curve generated from the control points.

    /// The curve that defines the shape of the track.

    pub fn new(points: Vec<Vec3>, radius: f32, circle_segments: u32, rings: usize) -> Track {

    pub fn new(curve: CubicCurve<Vec3>, radius: f32, circle_segments: u32, rings: usize) -> Track {

            points: points.clone(),
            curve: CubicCardinalSpline::new(0.5, points).to_curve(),

            curve: curve,

	    let sz = track.curve.segments().len();

                track.points.len() as f32 * t as f32 / track.rings as f32,

		sz as f32 * t as f32 / track.rings as f32,

                        .position(track.points.len() as f32 * t as f32 / track.rings as f32),

                        .position(sz as f32 * t as f32 / track.rings as f32),

    let track = Track::new(curve_points, 1.0, 16, 200);

    let track = Track::new(CubicCardinalSpline::new(0.5, curve_points).to_curve(), 1.0, 16, 200);