BezierSpline.GetVelocity C# (CSharp) Method

    public Vector3 GetVelocity(float t)
    {
        int i;

        if (t >= 1f) {
            t = 1f;

            i = points.Length - 4;
        } else {
            t = Mathf.Clamp01(t) * CurveCount;

            i = (int)t;
            t -= i; // [0, 1]

            i *= 3;
        }

        return transform.TransformPoint(
            CatmullRom.GetFirstDerivative (points[i], points[i+1], points[i+2], points[i+3], t)
            );
    }

 public Vector3 GetInitVelocity(Node n)
 {
     if (n == _edgeVertices[0])
     {
         return(curve.GetVelocity(0));
     }
     else
     {
         return(-curve.GetVelocity(1));
     }
 }