This demo allows you to move both the endpoints of a Bézier curve (large green and red dots) and the control points (small green and red dots), then to animate a dot from the origin (green) to the end (red).
Fifty points along the curve will be mapped, as the value for t ranges from 0 to 1. You'll need to force screen redraws between animations by dragging the controls around if you want a clean path (there's no error-trapping implemented, don't drop the controls off of the edge of the stage!). I've posted this as a .dir so that you can pull the source code out of your browser cache. Or you can download a ZIP archive.
This Demo requires Shockwave for Director 5.