1 Introduction.- 2 Least Squares Orthogonal Distance.- 3 General Properties of Splines.- 4 ODF using a cubic Bézier.- 5 Topology of Merges/Crossovers.- 6 ODF using a 5-Point B-spline.- 7 ODF using a 6-Point B-spline.- 8 ODF using a quartic Bézier.- 9 ODF using a Beta2-spline.- 10 ODF using a Beta1-spline.- 11 Conclusions.