I’m porting the classic Graphic Gem for computing the closest point on a Bezier curve to an arbitrary point from C to AS3. The Gem code only works for cubic Beziers, so that is the starting point for testing. My goal is to provide a utility that works for quadratic or cubic curves. Composite Bezier curves or splines are generally used to fit a larger set of points, with each segment composed of a cubic Bezier.
The first pass of the port is complete, although more testing is required before extending the code to work with quadratics.
When the BezierUtils class is complete, I’ll post two new online demos and an update of the Singularity code base. This will be used as a starting point for discussion of issues involving cusps and alternate optima.
The Algorithmist 
What’s a graphic gem?
http://tog.acm.org/GraphicsGems/
regards,
– jim
Why you don’t use this excellent lib :
http://bezier.ru/wp-content/uploads/2008/06/bezier.swf?demo=2
http://code.google.com/p/bezier/
I’m less interested in the raw capability (for personal use) and much more interested in a vehicle to use for teaching and demonstration of various algorithms. That potential is maximized if I can tightly integrate TechNotes and other demos with my own application code.
thanks,
– jim