用惯了jquery的同学,相信都很欣赏其动画引擎。确实相对比较完善!如果,如果想像力足够丰富的话,相信可以做出超出想像的效果。当然,跟2d库比起来,还是相差相当一段距离。jquery压根也不是专门为动画而设计的。模拟真实世界方面,还是不足的。但在web世界里还是游刃有余的。动画其实一直是flash的专属领地(web区哉)。只是它常常沦为黑客攻击的漏洞所在,而且要装插件,有时候文件实在太大,而且性耗实在是高啊。html5出现后,其实adobe自己都转移阵地到html5了。当然,我觉得很长一段时间内,flash是不会被放弃的。
长话短说,步入正题。仿照flash的动画原理,自己写了一个非常简单的js动画引擎。
首先,用过flash的同学都知道。flash有个时间线,上面布满了“帧”。其实每个帧都是一个镜头,镜头连贯起来就是一副动画效果。其实,这跟电影的原理也一样的,小时候玩过胶片的都知道,对着光可以看到一副副的镜头。人眼分辨两个画面的连贯是有时间限度的。如果想看不到两个画面变换时的闪烁大概30帧/秒左右,电影是24帧的。所以,如果能保证,动画切换能保证每秒30次,基本上,就做到了动画的流畅效果,但是这取决环境。所以具体情况,具体而定,其实关于这方面的知识我也是一知半解。就这个动画引擎而言,了解这么多也差不多足够了,有兴趣可以查找相关知识!
下面开始说说设计原理。
首先需要一个帧频,也就是多少帧每秒。如果有了总用时,就可以计算出整个动画下来有多少个“画面”(总帧数)。这种设计,显然有个不足的地方,不能保证时间正好是个整数帧。除非1ms一帧。这是一个网友提出来的,我感觉不好就没有采用。所以这个引擎是有时间误差的。有了总帧数,当动画运行到最后一帧的时候,整个动画也就播放完。如果需要重复播放,重新把当前帧归0。这种动画有一个好处,就可以直接运行到指定帧。也就是flash里的gotoAndStop和gotoAndPlay。其实整个动画设计原理都是照着flash实现的。包括一个很重要的方法:enterFrame。位置就是根据进入当前帧来计算的。还有其它一些方法:stop、play、next......等等因为目前来说,这个引擎是写非常简单和粗糙的,先不说这么详细了。下面先上代码和示例吧!
animate.js 动画核心
复制代码 代码如下:
var animation = function(obj) {
this.obj = obj;
this.frames = 0;
this.timmer = undefined;
this.running = false;
this.ms = [];
}
animation.prototype = {
fps: 36,
init: function(props, duration, tween) {
//console.log('初始化');
this.curframe = 0;
this.initstate = {};
this.props = props;
this.duration = duration || 1000;
this.tween = tween || function(t, b, c, d) {
return t * c / d + b;
};
this.frames = Math.ceil(this.duration * this.fps/1000);
for (var prop in this.props) {
this.initstate[prop] = {
from: parseFloat($util.dom.getStyle(this.obj, prop)),
to: parseFloat(this.props[prop])
};
}
},
start: function() {
if (!this.running && this.hasNext()) {
//console.log('可以执行...');
this.ms.shift().call(this)
}
return this;
},
//开始播放
play: function(callback) {
//console.log('开始动画!');
var that = this;
this.running = true;
if (this.timmer) {
this.stop();
}
this.timmer = setInterval(function() {
if (that.complete()) {
that.stop();
that.running = false;
if (callback) {
callback.call(that);
}
return;
}
that.curframe++;
that.enterFrame.call(that);
},
/ this.fps);
return this;
},
// 停止动画
stop: function() {
//console.log('结束动画!');
if (this.timmer) {
clearInterval(this.timmer);
// 清除掉timmer id
this.timmer = undefined;
}
},
go: function(props, duration, tween) {
var that = this;
//console.log(tween)
this.ms.push(function() {
that.init.call(that, props, duration, tween);
that.play.call(that, that.start);
});
return this;
},
//向后一帧
next: function() {
this.stop();
this.curframe++;
this.curframe = this.curframe > this.frames ? this.frames: this.curframe;
this.enterFrame.call(this);
},
//向前一帧
prev: function() {
this.stop();
this.curframe--;
this.curframe = this.curframe < 0 ? 0 : this.curframe;
this.enterFrame.call(this);
},
//跳跃到指定帧并播放
gotoAndPlay: function(frame) {
this.stop();
this.curframe = frame;
this.play.call(this);
},
//跳到指定帧停止播放
gotoAndStop: function(frame) {
this.stop();
this.curframe = frame;
this.enterFrame.call(this);
},
//进入帧动作
enterFrame: function() {
//console.log('进入帧:' + this.curframe)
var ds;
for (var prop in this.initstate) {
//console.log('from: ' + this.initstate[prop]['from'])
ds = this.tween(this.curframe, this.initstate[prop]['from'], this.initstate[prop]['to'] - this.initstate[prop]['from'], this.frames).toFixed(2);
//console.log(prop + ':' + ds)
$util.dom.setStyle(this.obj, prop, ds)
}
},
//动画结束
complete: function() {
return this.curframe >= this.frames;
},
hasNext: function() {
return this.ms.length > 0;
}
}
下面是一个简单的工具,其中有所用到的缓动公式:
util.js
复制代码 代码如下:
$util = {
/**
* 类型检测
*/
type : function(obj){
var rep = /\[object\s+(\w+)\]/i;
var str = Object.prototype.toString.call(obj).toLowerCase();
str.match(rep);
return RegExp.$1;
},
/**
* 深拷贝
*/
$unlink :function (object){
var unlinked;
switch ($type(object)){
case 'object':
unlinked = {};
for (var p in object) {
unlinked[p] = $unlink(object[p]);
}
break;
case 'array':
unlinked = [];
for (var i = 0, l = object.length; i < l; i++) {
unlinked[i] = $unlink(object[i]);
}
break;
default: return object;
}
return unlinked;
},
/**
*Dom 相关操作
*/
dom:{
$: function(id) {
return document.getElementById(id);
},
getStyle: function(obj, prop) {
var style = obj.currentStyle || window.getComputedStyle(obj, '');
if (obj.style.filter) {
return obj.style.filter.match(/\d+/g)[0];
}
return style[prop];
},
setStyle: function(obj, prop, val) {
switch (prop) {
case 'opacity':
if($util.client.browser.ie){
obj.style.filter = 'alpha(' + prop + '=' + val*100 + ')'
}else{
obj.style[prop] = val;
}
break;
default:
obj.style[prop] = val + 'px';
break;
}
},
setStyles: function(obj, props) {
for (var prop in props) {
switch (prop) {
case 'opacity':
if($util.client.browser.ie){
obj.style.filter = 'alpha(' + prop + '=' + props[prop] + ')'
}else{
obj.style[prop] = props[prop];
}
break;
default:
obj.style[prop] = props[prop] + 'px';
break;
}
}
}
},
/**
*Event 事件相关
*/
evt : {
addEvent : function(oTarget, sEventType, fnHandler) {
if (oTarget.addEventListener) {
oTarget.addEventListener(sEventType, fnHandler, false);
} else if (oTarget.attachEvent) {
oTarget.attachEvent("on" + sEventType, fnHandler);
} else {
oTarget["on" + sEventType] = fnHandler;
}
},
rmEvent : function removeEventHandler (oTarget, sEventType, fnHandler) {
if (oTarget.removeEventListener) {
oTarget.removeEventListener(sEventType, fnHandler, false);
} else if (oTarget.detachEvent) {
oTarget.detachEvent("on" + sEventType, fnHandler);
} else {
oTarget["on" + sEventType] = null;
}
}
},
/**
*Ajax 异步加载
*/
ajax : {
request:function (options) {
var xhr, res;
var url = options.url,
context = options.context,
success = options.success,
type = options.type,
datatype = options.datatype,
async = options.async,
send = options.send,
headers = options.headers;
try {
xhr = new XMLHttpRequest();
} catch(e) {
try {
xhr = new ActiveXObject('MSXML2.XMLHTTP');
} catch(e) {
xhr = new ActiveXObject('Microsoft.XMLHTTP');
}
}
xhr.onreadystatechange = function() {
if (xhr.readyState == 4 && xhr.status == 200) {
res = xhr.responseText;
success(res);
}
}
xhr.open(type, url, async);
xhr.send(send);
}
},
/**
*Array 数组相关
*/
array : {
minIndex : function(ary){
return Math.min.apply(null,ary);
},
maxitem : function(ary){
return Math.max.apply(null,ary);
}
},
/**
*Client 客户端检测
*/
client : function(){
// 浏览器渲染引擎 engines
var engine = {
ie: 0,
gecko: 0,
webkit: 0,
khtml: 0,
opera: 0,
//complete version
ver: null
};
// 浏览器
var browser = {
//browsers
ie: 0,
firefox: 0,
safari: 0,
konq: 0,
opera: 0,
chrome: 0,
//specific version
ver: null
};
// 客户端平台platform/device/OS
var system = {
win: false,
mac: false,
x11: false,
//移动设备
iphone: false,
ipod: false,
ipad: false,
ios: false,
android: false,
nokiaN: false,
winMobile: false,
//game systems
wii: false,
ps: false
};
// 检测浏览器引擎
var ua = navigator.userAgent;
if (window.opera){
engine.ver = browser.ver = window.opera.version();
engine.opera = browser.opera = parseFloat(engine.ver);
} else if (/AppleWebKit\/(\S+)/.test(ua)){
engine.ver = RegExp["$1"];
engine.webkit = parseFloat(engine.ver);
//figure out if it's Chrome or Safari
if (/Chrome\/(\S+)/.test(ua)){
browser.ver = RegExp["$1"];
browser.chrome = parseFloat(browser.ver);
} else if (/Version\/(\S+)/.test(ua)){
browser.ver = RegExp["$1"];
browser.safari = parseFloat(browser.ver);
} else {
//approximate version
var safariVersion = 1;
if (engine.webkit < 100){
safariVersion = 1;
} else if (engine.webkit < 312){
safariVersion = 1.2;
} else if (engine.webkit < 412){
safariVersion = 1.3;
} else {
safariVersion = 2;
}
browser.safari = browser.ver = safariVersion;
}
} else if (/KHTML\/(\S+)/.test(ua) || /Konqueror\/([^;]+)/.test(ua)){
engine.ver = browser.ver = RegExp["$1"];
engine.khtml = browser.konq = parseFloat(engine.ver);
} else if (/rv:([^\)]+)\) Gecko\/\d{8}/.test(ua)){
engine.ver = RegExp["$1"];
engine.gecko = parseFloat(engine.ver);
//determine if it's Firefox
if (/Firefox\/(\S+)/.test(ua)){
browser.ver = RegExp["$1"];
browser.firefox = parseFloat(browser.ver);
}
} else if (/MSIE ([^;]+)/.test(ua)){
engine.ver = browser.ver = RegExp["$1"];
engine.ie = browser.ie = parseFloat(engine.ver);
}
//detect browsers
browser.ie = engine.ie;
browser.opera = engine.opera;
//detect platform
var p = navigator.platform;
system.win = p.indexOf("Win") == 0;
system.mac = p.indexOf("Mac") == 0;
system.x11 = (p == "X11") || (p.indexOf("Linux") == 0);
//detect windows operating systems
if (system.win){
if (/Win(?:dows )?([^do]{2})\s?(\d+\.\d+)?/.test(ua)){
if (RegExp["$1"] == "NT"){
switch(RegExp["$2"]){
case "5.0":
system.win = "2000";
break;
case "5.1":
system.win = "XP";
break;
case "6.0":
system.win = "Vista";
break;
case "6.1":
system.win = "7";
break;
default:
system.win = "NT";
break;
}
} else if (RegExp["$1"] == "9x"){
system.win = "ME";
} else {
system.win = RegExp["$1"];
}
}
}
//mobile devices
system.iphone = ua.indexOf("iPhone") > -1;
system.ipod = ua.indexOf("iPod") > -1;
system.ipad = ua.indexOf("iPad") > -1;
system.nokiaN = ua.indexOf("NokiaN") > -1;
//windows mobile
if (system.win == "CE"){
system.winMobile = system.win;
} else if (system.win == "Ph"){
if(/Windows Phone OS (\d+.\d+)/.test(ua)){;
system.win = "Phone";
system.winMobile = parseFloat(RegExp["$1"]);
}
}
//determine iOS version
if (system.mac && ua.indexOf("Mobile") > -1){
if (/CPU (?:iPhone )?OS (\d+_\d+)/.test(ua)){
system.ios = parseFloat(RegExp.$1.replace("_", "."));
} else {
system.ios = 2; //can't really detect - so guess
}
}
//determine Android version
if (/Android (\d+\.\d+)/.test(ua)){
system.android = parseFloat(RegExp.$1);
}
//gaming systems
system.wii = ua.indexOf("Wii") > -1;
system.ps = /playstation/i.test(ua);
//return it
return {
engine: engine,
browser: browser,
system: system
};
}(),
/**
*Tween 缓动相关
*/
tween: {
Linear: function(t, b, c, d) {
return c * t / d + b;
},
Quad: {
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;
},
easeInOut: function(t, b, c, d) {
if ((t /= d / 2) < 1) return c / 2 * t * t + b;
return - c / 2 * ((--t) * (t - 2) - 1) + b;
}
},
Cubic: {
easeIn: function(t, b, c, d) {
return c * (t /= d) * t * t + b;
},
easeOut: function(t, b, c, d) {
return c * ((t = t / d - 1) * t * t + 1) + b;
},
easeInOut: 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;
}
},
Quart: {
easeIn: function(t, b, c, d) {
return c * (t /= d) * t * t * t + b;
},
easeOut: function(t, b, c, d) {
return - c * ((t = t / d - 1) * t * t * t - 1) + b;
},
easeInOut: 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;
}
},
Quint: {
easeIn: function(t, b, c, d) {
return c * (t /= d) * t * t * t * t + b;
},
easeOut: function(t, b, c, d) {
return c * ((t = t / d - 1) * t * t * t * t + 1) + b;
},
easeInOut: 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;
}
},
Sine: {
easeIn: function(t, b, c, d) {
return - c * Math.cos(t / d * (Math.PI / 2)) + c + b;
},
easeOut: function(t, b, c, d) {
return c * Math.sin(t / d * (Math.PI / 2)) + b;
},
easeInOut: function(t, b, c, d) {
return - c / 2 * (Math.cos(Math.PI * t / d) - 1) + b;
}
},
Expo: {
easeIn: function(t, b, c, d) {
return (t == 0) ? b: c * Math.pow(2, 10 * (t / d - 1)) + b;
},
easeOut: function(t, b, c, d) {
return (t == d) ? b + c: c * ( - Math.pow(2, -10 * t / d) + 1) + b;
},
easeInOut: 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;
}
},
Circ: {
easeIn: function(t, b, c, d) {
return - c * (Math.sqrt(1 - (t /= d) * t) - 1) + b;
},
easeOut: function(t, b, c, d) {
return c * Math.sqrt(1 - (t = t / d - 1) * t) + b;
},
easeInOut: 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;
}
},
Elastic: {
easeIn: 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;
},
easeOut: 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);
},
easeInOut: 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;
}
},
Back: {
easeIn: function(t, b, c, d, s) {
if (s == undefined) s = 1.70158;
return c * (t /= d) * t * ((s + 1) * t - s) + b;
},
easeOut: 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;
},
easeInOut: 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;
}
},
Bounce: {
easeIn: function(t, b, c, d) {
return c - Tween.Bounce.easeOut(d - t, 0, c, d) + b;
},
easeOut: 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;
}
},
easeInOut: function(t, b, c, d) {
if (t < d / 2) return Tween.Bounce.easeIn(t * 2, 0, c, d) * .5 + b;
else return Tween.Bounce.easeOut(t * 2 - d, 0, c, d) * .5 + c * .5 + b;
}
}
}
}
下面是个应用:
复制代码 代码如下:
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<title>无标题文档</title>
<script src="/UploadFiles/2021-04-02/util.js"><script src="animate.js"><style type="text/css">
body{behavior:url("csshover.htc")}
*{padding:0;margin:0}
.mianbox{width:480px;margin:50px auto;height:240px;}
.leftbtn{width:20px;background:#eee;border:1px solid #ddd;float:left;margin-right:8px;height:240px;}
.leftbtn:hover{background:#fff}
.rightbtn{width:20px;background:#eee;border:1px solid #ddd;float:right;height:240px;}
.rightbtn:hover{background:#fff}
.con{width:420px;float:left;height:240px;overflow:hidden;position:relative}
.con ul{ white-space:nowrap;font-size:0;position:absolute;left:0;top:0;}
.con li{display:inline; vertical-align:bottom;margin-right:10px}
</style>
</head>
<body>
<div class="mianbox">
<div class="leftbtn" id="leftbtn"></div>
<div class="con">
<ul>
<li><img src="/UploadFiles/2021-04-02/2969675_091845785000_2.jpg"> <li><img src="http://pic23.nipic.com/20120818/9715349_114354586392_2.jpg"> <li><img src="/UploadFiles/2021-04-02/9715349_154806479182_2.jpg"> <li><img src="http://pic20.nipic.com/20120329/9715349_162301568121_2.jpg"> <li><img src="/UploadFiles/2021-04-02/9715349_160522342186_2.jpg"> <li><img src="http://pic23.nipic.com/20120824/9715349_160651385195_2.jpg"> <li><img src="/UploadFiles/2021-04-02/9715349_163520278182_2.jpg"> <li><img src="http://pic23.nipic.com/20120827/9715349_110350505124_2.jpg"> </ul>
</div>
<div class="rightbtn" id="rightbtn"></div>
</div>
<script>
/**
* @para obj 内容对象
* @para lbtn 左按钮
* @para rbtn 右按钮
* @para w 每次滚动的宽
* @para duration 每次运行时间
* @para tween 缓动类型
*/
function scOnce(obj, lbtn, rbtn, w, autotime, duration,tween){
var am = new animation(_ul),
step=0,
ulen = obj.scrollWidth,
timmerm
dr = 'left',
that = this;
// 最右端?
function isr(){
return parseInt($util.dom.getStyle(obj, 'left')) >=0;
}
// 最左端?
function isl(){
return ulen - Math.abs(parseInt($util.dom.getStyle(obj, 'left')))-10 <= w;
}
if(isr()&&isl())
return;
// 左移
this.goleft = function (){
step += -1*w;
am.go({left:step+"px"},duration,tween).start();
}
// 右移
this.goright = function (){
step += w;
am.go({left:step+"px"},duration,tween).start();
}
// 注册左按钮事件
$util.evt.addEvent(lbtn,'click',function(){
isl()? that.goright():that.goleft();
})
// 注册右按钮事件
$util.evt.addEvent(rbtn,'click',function(){
isr()? that.goleft():that.goright();
})
$util.evt.addEvent(rbtn,'mouseover',function(){
clearTimeout(timmer);
})
$util.evt.addEvent(lbtn,'mouseover',function(){
clearTimeout(timmer);
})
$util.evt.addEvent(rbtn,'mouseout',function(){
timmer = setInterval(auto,autotime);
})
$util.evt.addEvent(lbtn,'mouseout',function(){
timmer = setInterval(auto,autotime);
})
function auto(){
if(isl()){
dr = "right";
}
if(isr()){
dr = "left";
}
that['go'+dr]();
}
timmer = setInterval(auto,autotime);
}
var _ul = document.getElementsByTagName('ul')[0],
lbtn = document.getElementById('leftbtn'),
rbtn = document.getElementById('rightbtn');
var startgo = new scOnce(_ul,lbtn,rbtn,430,3000,500,$util.tween.Quint.easeInOut);
</script>
</body>
</html>
animate
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稳了!魔兽国服回归的3条重磅消息!官宣时间再确认!
昨天有一位朋友在大神群里分享,自己亚服账号被封号之后居然弹出了国服的封号信息对话框。
这里面让他访问的是一个国服的战网网址,com.cn和后面的zh都非常明白地表明这就是国服战网。
而他在复制这个网址并且进行登录之后,确实是网易的网址,也就是我们熟悉的停服之后国服发布的暴雪游戏产品运营到期开放退款的说明。这是一件比较奇怪的事情,因为以前都没有出现这样的情况,现在突然提示跳转到国服战网的网址,是不是说明了简体中文客户端已经开始进行更新了呢?