You’ll find this spline function useful, whenever you want to connect a number of points with a nice, smooth curve instead of a jaggy series of straight lines, as it will interpolate the missing points in between (sorry for this perfectly un-mathematical description of a spline).  


  • to visualize statistical data with nice curves
  • to recreate shapes which have formerly been reduced with a Line Generalization tool.  To first reduce the drawing data and to later re-interpolate it can make sense as it  reduces the amount of data that is being sent back and forth betweem client and server.
    Another use case is  to smooth the rather shaky lines that are drawn with the mouse.

Catmull-Rom Spline

(developed and originally published in 2005)