Flash AS3.0 的Bezier曲线类，可以根据给定的2至4个点确定一条Bezier曲线，并可方便地实现曲线的移动，求曲线与直线，曲线与曲线的交点。-Flash AS3.0 class of Bezier curves, can be given two to four points determine a Bezier curve, the curve can easily achieve the movement of demand curve and a straight line,