jquery easing の引数

  • x: null 不要。応用時はなしでおｋ
  • t: current time
  • b: beginnIng value (start value)
  • c: change In value (end value)
  • d: duration (total time) = fps
  • s: stress? 任意。反動などの強さの調整
	easeInBack: function (x, t, b, c, d, s) {
		if (s == undefined) s = 1.70158;
		return c*(t/=d)*t*((s+1)*t - s) + b;
	},

を抜き出したなら、↓みたいにするといい

var easeInBack = function (t, b, c, d, s) {
	if (s == undefined) s = 1.70158;
	return c*(t/=d)*t*((s+1)*t - s) + b;
}

var currentTime = 0;
var startValue = 0;
var endValue = 100;
var fps = 32;
(function(){
	console.log(
		easeInBack(currentTime, startValue, endValue, fps)
	);
	currentTime ++;
	if(currentTime <= fps){
		setTimeout(arguments.callee, 1000/fps);
	}
})();