Javascript 如何在动画帧上使用减速算法？

我想在一个动画上使用减速，我正在通过请求动画帧运行！我知道如何实现速度，对于减速，我找到了这个项目

https://github.com/gre/bezier-easing

。我现在是TIAS，但不知道该怎么做

https://github.com/gre/bezier-easing

。我希望最后速度会下降

velocity我找到了解决方案，为我工作：

// http://cubic-bezier.com/#0.25,0.25,0,1
var easing = BezierEasing(0.25, 0.25, 0, 0.9),
            i = 0,
            stepIncrementAmount = 0.25;

(function loop() {

    // sorry about the * 100 but that's what $knob expects, scale range 0 > 100, and easing needs 0 to 1
    velocity = easing(i / 100) * 100;

    if (velocity <= parseFloat(attrs.radialBarPercentage)) {
        $knob.val(velocity).trigger('change');
        i += stepIncrementAmount;
        animationFrame.request(loop);
    }

})();

//http://cubic-bezier.com/#0.25,0.25,0,1
var宽松=贝塞尔宽松（0.25,0.25,0,0.9），
i=0，
逐步递增金额=0.25；
（函数循环（）{
//抱歉*100，但这正是$knob所期望的，标度范围0>100，缓和需要0到1
速度=缓解（i/100）*100；
if（速度
// http://cubic-bezier.com/#0.25,0.25,0,1
var easing = BezierEasing(0.25, 0.25, 0, 0.9),
            i = 0,
            stepIncrementAmount = 0.25;

(function loop() {

    // sorry about the * 100 but that's what $knob expects, scale range 0 > 100, and easing needs 0 to 1
    velocity = easing(i / 100) * 100;

    if (velocity <= parseFloat(attrs.radialBarPercentage)) {
        $knob.val(velocity).trigger('change');
        i += stepIncrementAmount;
        animationFrame.request(loop);
    }

})();