/*
* 1.起点
* 2.终点
* 3.变化量 = 终点-起点
* 4.帧数 = 总时长/定时器时间间隔
* 5.步长 = 变化量/帧数
* 参数
* obj 运动对象
* myJson 运动属性目标值
* time 运动时间
* tweenString 运动方式
* callBack 回调函数
*
* */
function animate(obj ,myJson, time,tweenString ,callBack) {
var startJson = {}; //开始点
var targetJson = {}; //结束点
var deltaJson = {}; //变化量
var maxCount = Math.floor(time/20); //帧数
var timer = null; //定时器
var count = 0; //当前帧的编号
//函数重载
if(arguments.length === 3){
tweenString = "Linear";
}else if(arguments.length === 4){
switch (typeof(arguments[3])){
case "string" :
break;
case "function" :
callBack = arguments[3];
tweenString = "Linear";
break;
}
}
for(var k in myJson){
startJson[k] = parseFloat(getStyle(obj,k)); //获取所有属性初始值
targetJson[k] = parseFloat(myJson[k]); //获取所有属性目标值
deltaJson[k] = targetJson[k] - startJson[k]; //获取所有属性的变化量
}
timer = setInterval(
function () {
for (var k in myJson){
var number = Tween[tweenString](count, startJson[k], deltaJson[k], maxCount);//拿到当前帧的位置
if(k === "opacity"){
obj.style[k] = number;
obj.style.filter = "alpha(opacity = "+number*100+")";
}else {
obj.style[k] = number + "px";
}
}
count++;
if(count === maxCount){
for(var k in myJson){
if(k === "opacity"){
obj.style[k] = targetJson[k];
obj.style.filter = "alpha(opacity = "+targetJson[k]*100+")"
}else{
obj.style[k] = targetJson[k] + "px";
}
}
clearInterval(timer);
callBack && callBack.call(obj);
}
}
,11)
//获取元素实际样式的方法
function getStyle(obj , property){
return obj.currentStyle ? obj.currentStyle[property] : getComputedStyle(obj)[property];
}
//缓冲公式
/*
* 第一个参数 t 表示当前帧的编号
* 第二个参数 b 表示起始位置
* 第三个参数 c 表示变化量
* 第四个参数 d 表示总帧数
* */
var Tween = {
Linear: function(t, b, c, d) {
return c * t / d + b;
},
//二次的
QuadEaseIn: function(t, b, c, d) {
return c * (t /= d) * t + b;
},
QuadEaseOut: function(t, b, c, d) {
return -c * (t /= d) * (t - 2) + b;
},
QuadEaseInOut: function(t, b, c, d) {
if ((t /= d / 2) < 1) return c / 2 * t * t + b;
return -c / 2 * ((--t) * (t - 2) - 1) + b;
},
//三次的
CubicEaseIn: function(t, b, c, d) {
return c * (t /= d) * t * t + b;
},
CubicEaseOut: function(t, b, c, d) {
return c * ((t = t / d - 1) * t * t + 1) + b;
},
CubicEaseInOut: function(t, b, c, d) {
if ((t /= d / 2) < 1) return c / 2 * t * t * t + b;
return c / 2 * ((t -= 2) * t * t + 2) + b;
},
//四次的
QuartEaseIn: function(t, b, c, d) {
return c * (t /= d) * t * t * t + b;
},
QuartEaseOut: function(t, b, c, d) {
return -c * ((t = t / d - 1) * t * t * t - 1) + b;
},
QuartEaseInOut: function(t, b, c, d) {
if ((t /= d / 2) < 1) return c / 2 * t * t * t * t + b;
return -c / 2 * ((t -= 2) * t * t * t - 2) + b;
},
QuartEaseIn: function(t, b, c, d) {
return c * (t /= d) * t * t * t * t + b;
},
QuartEaseOut: function(t, b, c, d) {
return c * ((t = t / d - 1) * t * t * t * t + 1) + b;
},
QuartEaseInOut: function(t, b, c, d) {
if ((t /= d / 2) < 1) return c / 2 * t * t * t * t * t + b;
return c / 2 * ((t -= 2) * t * t * t * t + 2) + b;
},
//正弦的
SineEaseIn: function(t, b, c, d) {
return -c * Math.cos(t / d * (Math.PI / 2)) + c + b;
},
SineEaseOut: function(t, b, c, d) {
return c * Math.sin(t / d * (Math.PI / 2)) + b;
},
SineEaseInOut: function(t, b, c, d) {
return -c / 2 * (Math.cos(Math.PI * t / d) - 1) + b;
},
ExpoEaseIn: function(t, b, c, d) {
return (t == 0) ? b : c * Math.pow(2, 10 * (t / d - 1)) + b;
},
ExpoEaseOut: function(t, b, c, d) {
return (t == d) ? b + c : c * (-Math.pow(2, -10 * t / d) + 1) + b;
},
ExpoEaseInOut: function(t, b, c, d) {
if (t == 0) return b;
if (t == d) return b + c;
if ((t /= d / 2) < 1) return c / 2 * Math.pow(2, 10 * (t - 1)) + b;
return c / 2 * (-Math.pow(2, -10 * --t) + 2) + b;
},
CircEaseIn: function(t, b, c, d) {
return -c * (Math.sqrt(1 - (t /= d) * t) - 1) + b;
},
CircEaseOut: function(t, b, c, d) {
return c * Math.sqrt(1 - (t = t / d - 1) * t) + b;
},
CircEaseInOut: function(t, b, c, d) {
if ((t /= d / 2) < 1) return -c / 2 * (Math.sqrt(1 - t * t) - 1) + b;
return c / 2 * (Math.sqrt(1 - (t -= 2) * t) + 1) + b;
},
ElasticEaseIn: function(t, b, c, d, a, p) {
if (t == 0) return b;
if ((t /= d) == 1) return b + c;
if (!p) p = d * .3;
if (!a || a < Math.abs(c)) {
a = c;
var s = p / 4;
} else var s = p / (2 * Math.PI) * Math.asin(c / a);
return -(a * Math.pow(2, 10 * (t -= 1)) * Math.sin((t * d - s) * (2 * Math.PI) / p)) + b;
},
ElasticEaseOut: function(t, b, c, d, a, p) {
if (t == 0) return b;
if ((t /= d) == 1) return b + c;
if (!p) p = d * .3;
if (!a || a < Math.abs(c)) {
a = c;
var s = p / 4;
} else var s = p / (2 * Math.PI) * Math.asin(c / a);
return (a * Math.pow(2, -10 * t) * Math.sin((t * d - s) * (2 * Math.PI) / p) + c + b);
},
ElasticEaseInOut: function(t, b, c, d, a, p) {
if (t == 0) return b;
if ((t /= d / 2) == 2) return b + c;
if (!p) p = d * (.3 * 1.5);
if (!a || a < Math.abs(c)) {
a = c;
var s = p / 4;
} else var s = p / (2 * Math.PI) * Math.asin(c / a);
if (t < 1) return -.5 * (a * Math.pow(2, 10 * (t -= 1)) * Math.sin((t * d - s) * (2 * Math.PI) / p)) + b;
return a * Math.pow(2, -10 * (t -= 1)) * Math.sin((t * d - s) * (2 * Math.PI) / p) * .5 + c + b;
},
//冲过头系列
BackEaseIn: function(t, b, c, d, s) {
if (s == undefined) s = 1.70158;
return c * (t /= d) * t * ((s + 1) * t - s) + b;
},
BackEaseOut: function(t, b, c, d, s) {
if (s == undefined) s = 1.70158;
return c * ((t = t / d - 1) * t * ((s + 1) * t + s) + 1) + b;
},
BackEaseInOut: function(t, b, c, d, s) {
if (s == undefined) s = 1.70158;
if ((t /= d / 2) < 1) return c / 2 * (t * t * (((s *= (1.525)) + 1) * t - s)) + b;
return c / 2 * ((t -= 2) * t * (((s *= (1.525)) + 1) * t + s) + 2) + b;
},
//弹跳系列
BounceEaseIn: function(t, b, c, d) {
return c - Tween.BounceEaseOut(d - t, 0, c, d) + b;
},
BounceEaseOut: function(t, b, c, d) {
if ((t /= d) < (1 / 2.75)) {
return c * (7.5625 * t * t) + b;
} else if (t < (2 / 2.75)) {
return c * (7.5625 * (t -= (1.5 / 2.75)) * t + .75) + b;
} else if (t < (2.5 / 2.75)) {
return c * (7.5625 * (t -= (2.25 / 2.75)) * t + .9375) + b;
} else {
return c * (7.5625 * (t -= (2.625 / 2.75)) * t + .984375) + b;
}
},
BounceEaseInOut: function(t, b, c, d) {
if (t < d / 2) return Tween.BounceEaseIn(t * 2, 0, c, d) * .5 + b;
else return Tween.BounceEaseOut(t * 2 - d, 0, c, d) * .5 + c * .5 + b;
}
}
}