Cubic Catmull-Rom Spline interpolation. Based onhttp://www.cemyuksel.com/research/catmullrom_param/catmullrom.pdfCurves are guaranteed to pass through the control points and are easily chained together. Equation supports abitrary parameterization. eg. Uniform=0,1,2,3 ; chordal= |Pn - Pn-1| ; centripetal = |Pn - Pn-1|^0.5 P0 - The control point preceding the interpolation range. P1 - The control point starting the interpolation range. P2 - The control point ending the interpolation range. P3 - The control point following the interpolation range. T0-3 - The interpolation parameters for the corresponding control points. T - The interpolation factor in the range 0 to 1. 0 returns P1. 1 returns P2.