动画函数MTween.js

Posted 2020-12-06 画画520

实现各种各样的动画效果

使用方法：MTween(init);

参数：init：（是个对象）{

                    el:obj,//元素

                    target:{attr:val},//元素属性及对应的目标点（是个对象，也就是可以设置多个属性及其值）！注意：如果是设置透明度和scale系列放大缩小的时候，比如想要把元素放大为原来的2倍，就要写为200，同理，透明度设置为1，就要写为100

                    time:1000,//时间（此时为1s）

                    type:"linear",//动画类型

                    callBack:fn,//回调函数（即，整个动画执行完之后要执行的函数）

                    callIn:fn//同步函数（即，动画在执行过程中同步执行的函数）

                }

前四个参数是必选参数，后两个是可选参数

动画类型的可选值有：

linear、easeIn、easeOut、easeBoth、easeInStrong、easeOutStrong、easeBothStrong、
elasticIn、elasticOut、elasticBoth、backIn、backOut、backBoth、bounceIn、bounceOut、bounceBoth

下面是我们封装的函数（因为下面的封装函数，里面涉及的知识点我已经在其他函数中详细解释了，所以，下面没写注释）

如果有什么疑问，可以看cssTransform，以及css函数封装，里面有注释，当然如果你只是要用这个函数的话，知道怎么用就可以，那直接把下面的引入你的代码中，然后直接使用即可

var Tween = {
linear: function (t, b, c, d){
return c*t/d + b;
},
easeIn: function(t, b, c, d){
return c*(t/=d)*t + b;
},
easeOut: function(t, b, c, d){
return -c *(t/=d)*(t-2) + b;
},
easeBoth: function(t, b, c, d){
if ((t/=d/2) < 1) {
return c/2*t*t + b;
}
return -c/2 * ((--t)*(t-2) - 1) + b;
},
easeInStrong: function(t, b, c, d){
return c*(t/=d)*t*t*t + b;
},
easeOutStrong: function(t, b, c, d){
return -c * ((t=t/d-1)*t*t*t - 1) + b;
},
easeBothStrong: 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;
},
elasticIn: function(t, b, c, d, a, p){
if (t === 0) {
return b;
}
if ( (t /= d) == 1 ) {
return b+c;
}
if (!p) {
p=d*0.3;
}
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;
},
elasticOut: function(t, b, c, d, a, p){
if (t === 0) {
return b;
}
if ( (t /= d) == 1 ) {
return b+c;
}
if (!p) {
p=d*0.3;
}
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;
},
elasticBoth: function(t, b, c, d, a, p){
if (t === 0) {
return b;
}
if ( (t /= d/2) == 2 ) {
return b+c;
}
if (!p) {
p = d*(0.3*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 - 0.5*(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 )*0.5 + c + b;
},
backIn: function(t, b, c, d, s){
if (typeof s == ‘undefined‘) {
s = 1.70158;
}
return c*(t/=d)*t*((s+1)*t - s) + b;
},
backOut: function(t, b, c, d, s){
if (typeof s == ‘undefined‘) {
s = 2.70158; //回缩的距离
}
return c*((t=t/d-1)*t*((s+1)*t + s) + 1) + b;
},
backBoth: function(t, b, c, d, s){
if (typeof 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;
},
bounceIn: function(t, b, c, d){
return c - Tween[‘bounceOut‘](d-t, 0, c, d) + b;
},
bounceOut: 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 + 0.75) + b;
} else if (t < (2.5/2.75)) {
return c*(7.5625*(t-=(2.25/2.75))*t + 0.9375) + b;
}
return c*(7.5625*(t-=(2.625/2.75))*t + 0.984375) + b;
},
bounceBoth: function(t, b, c, d){
if (t < d/2) {
return Tween[‘bounceIn‘](t*2, 0, c, d) * 0.5 + b;
}
return Tween[‘bounceOut‘](t*2-d, 0, c, d) * 0.5 + c*0.5 + b;
}
};
function css(element, attr , val){
if(attr == "scale"||attr == "scaleX"
||attr == "scaleY"||attr == "scaleZ"
||attr == "rotateX"||attr == "rotateY"
||attr == "rotateZ"||attr == "rotate"
||attr == "skewX"||attr == "skewY"
||attr == "translateX"||attr == "translateY"
||attr == "translateZ") {
return cssTransform(element, attr, val);
}
if(arguments.length == 2){
var val = getComputedStyle(element)[attr];
if(attr==‘opacity‘){
val = Math.round(val*100);
}
return parseFloat(val);
}
if(attr == "opacity") {
element.style.opacity= val/100;
} else {
element.style[attr]= val + "px";
}
}
function cssTransform(element, attr, val){
if(!element.transform){
element.transform = {};
}
if(typeof val === "undefined"){
if(typeof element.transform[attr] === "undefined"){
switch(attr){
case "scale":
case "scaleX":
case "scaleY":
case "scaleZ":
element.transform[attr] = 100;
break;
default:
element.transform[attr] = 0;
}
}
return element.transform[attr];
} else {
element.transform[attr] = val;
var transformVal = "";
for(var s in element.transform){
switch(s){
case "scale":
case "scaleX":
case "scaleY":
case "scaleZ":
transformVal += " " + s + "("+(element.transform[s]/100)+")";
break;
case "rotate":
case "rotateX":
case "rotateY":
case "rotateZ":
case "skewX":
case "skewY":
transformVal += " " + s + "("+element.transform[s]+"deg)";
break;
default:
transformVal += " " + s + "("+element.transform[s]+"px)";
}
}
element.style.WebkitTransform = element.style.transform = transformVal;
}
}
function MTween(init){
var t = 0;
var b = {};
var c = {};
var d = init.time / 20;
for(var s in init.target){
b[s] = css(init.el, s);
c[s] = init.target[s] - b[s];
}
clearInterval(init.el.timer);
init.el.timer = setInterval(
function(){
t++;
if(t>d){
clearInterval(init.el.timer);
init.callBack&&init.callBack.call(init.el);
} else {
init.callIn&&init.callIn.call(init.el);
for(var s in b){
var val = Number((Tween[init.type](t,b[s],c[s],d)).toFixed(2));
css(init.el, s, val);
}
}
},
20
);
}

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版权声明：本文为CSDN博主「冰雪为融」的原创文章，遵循CC 4.0 BY-SA版权协议，转载请附上原文出处链接及本声明。
原文链接：https://blog.csdn.net/lhjuejiang/java/article/details/80538044