How to achieve focus map effect using js
The editor below will share with you an example of a simple focus map effect implemented in native js. It has a good reference value and I hope it will be helpful to everyone. Let’s follow the editor and take a look.
Use some packaged motion functions, mainly timers.
The effect is to automatically change pictures and picture descriptions at regular intervals.
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<style type="text/css">
ul,
li,
p,
h3 {
padding: 0;
margin: 0;
list-style: none;
}
img {
border: none;
vertical-align: top;
}
#bg_box {
width: 1000px;
height: 590px;
margin: 50px auto;
position: relative;
background: url(img/bg1.jpg) no-repeat;
}
.pic {
width: 440px;
height: 274px;
position: absolute;
top: 50px;
left: 220px;
overflow: hidden;
}
.li_box {
width: 1760px;
height: 274px;
position: absolute;
left: 0;
}
.tags {
width: 440px;
height: 80px;
position: absolute;
bottom: -80px;
background-image: linear-gradient(0deg, rgba(0, 0, 0, 0.4) 0%, rgba(255, 255, 255, 0) 100%);
color: white;
padding-left: 20px;
padding-top: 15px;
box-sizing: border-box;
}
.tags:nth-of-type(1) {
/*bottom: 0;*/
}
.img {
float: left;
width: 440px;
height: 274px;
}
h3 {
font: bold 20px/30px "微软雅黑";
}
p {
font: 16px/30px "微软雅黑";
}
</style>
<script src="tween.js"></script>
<script src="commom.js"></script>
<script type="text/javascript">
window.onload = function() {
//获取元素
var liBbox = $('ul')[0];
var li = $('li');
var tags = $('.tags')
var num = 0; //设置初始位置
Change()
function Change() {
var M = tags[num];
MTween(M, 'bottom', 0, 500, 'px', 'linear', function() { //先让描述内容出现
num++
if(num > li.length - 1) { //边界设置。
return;
}
setTimeout(function() {
MTween(M, 'bottom', -80, 500, 'px', 'linear', function() { //让描述内容不显示
MTween(liBbox, 'left', -num * 440, 800, 'px', 'linear', function() {
Change();
}); //切换图片
});
}, 1000)
});
}
}
</script>
</head>
<body>
<section id="bg_box">
<p class="pic">
<ul class="li_box">
<li>
<img class="img" src="img/a5.gif">
</li>
<li>
<img class="img" src="img/a6.gif">
</li>
<li>
<img class="img" src="img/a7.gif">
</li>
<li>
<img class="img" src="img/a8.gif">
</li>
</ul>
<p class="tags">
<h3 class="title">下雨了~~~</h3>
<p class="tag">这是一个适合在家睡觉的日子!!</p>
</p>
<p class="tags">
<h3 class="title">包饺子~~~</h3>
<p class="tag">一只会居家过日子的小狐狸！！</p>
</p>
<p class="tags">
<h3 class="title">生气了~~~</h3>
<p class="tag">吃掉好吃的就不生气了！！</p>
</p>
<p class="tags">
<h3 class="title">出发了~~~</h3>
<p class="tag">来一段说走就走的旅行!!</p>
</p>
</p>
</section>
</body>
</html>commom.js
function MTween(obj,attr,end,duration,unit,way,callBack){
if(obj.isAnim) return;
//obj开始运动了 自定义属性
obj.isAnim = true;
if(!way){ //如果用户没有选择运动方式就默认匀速
way = 'linear';
}
if(!unit){ //如果用户没有选择运动方式就默认匀速
unit = '';
}
var start = parseFloat(getStyle(obj,attr));//起始位置
// var end = 1000;//目标点
// var duration = 1000;//动画执行的总时间 单位是毫秒
var startTime = Date.now();
var s = end - start; //总路程
// var v = s/duration; //计算出来的速度
//每次20ms走一帧
clearInterval(timer);
var timer = 0;
timer = setInterval(function(){
var endTime = Date.now();
//计算出当前时间
var t = endTime-startTime;
if(t>=duration){
t = duration;
clearInterval(timer);//到达目标点要清除定时器
}
// obj.style[attr] = t*s/duration+start+'px';
// console.log(Tween[way](t,start,s,duration))
obj.style[attr] = Tween[way](t,start,s,duration)+unit;
//透明度的兼容处理
if(attr=='opacity'){
obj.style.filter = 'Alpha(opacity='+Tween[way](t,start,s,duration)*100+')';
}
if(t==duration){
obj.isAnim = false;
//等到上一个动画完成 然后再调用
if(callBack){
callBack();
}
}
},20);
}tween.js
/*
* t : time 已过时间 当前时间-初始时间
* b : begin 起始值
* c : count 总的运动值 总路程
* d : duration 持续时间 总时间
*
* s = vt; => c = t*c/d 这里只计算总共要运动的路程 ，不包括起始位置
*
* attrVal = t*c/d + b;
*
* 曲线方程
*
* */
//Tween.linear();
var Tween = {
linear: function (t, b, c, d){ //匀速
return c*t/d + b;
},
easeIn: function(t, b, c, d){ //加速曲线
return c*(t/=d)*t + b;
},
easeOut: function(t, b, c, d){ //减速曲线
return -c *(t/=d)*(t-2) + b;
},
easeBoth: function(t, b, c, d){ //加速减速曲线
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){ //加加速曲线
return c*(t/=d)*t*t*t + b;
},
easeOutStrong: function(t, b, c, d){ //减减速曲线
return -c * ((t=t/d-1)*t*t*t - 1) + b;
},
easeBothStrong: function(t, b, c, d){ //加加速减减速曲线
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){ //正弦衰减曲线（弹动渐入）
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){ //*正弦增强曲线（弹动渐出）
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){ //回退加速（回退渐入）
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 = 3.70158; //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){ //弹球减振（弹球渐出）
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;
}
}The above is what I compiled for you. I hope it will be helpful to everyone in the future.
Related articles:
Detailed introduction to the proxy mode (Proxy) in ES6
Detailed introduction to building webpack
How to implement file packaging using webpack
Using webpack to build vue scaffolding
How to implement calendar using Vue components (details Tutorial)
The above is the detailed content of How to achieve focus map effect using js. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
What should I do if I encounter garbled code printing for front-end thermal paper receipts?
Apr 04, 2025 pm 02:42 PM
Frequently Asked Questions and Solutions for Front-end Thermal Paper Ticket Printing In Front-end Development, Ticket Printing is a common requirement. However, many developers are implementing...
Demystifying JavaScript: What It Does and Why It Matters
Apr 09, 2025 am 12:07 AM
JavaScript is the cornerstone of modern web development, and its main functions include event-driven programming, dynamic content generation and asynchronous programming. 1) Event-driven programming allows web pages to change dynamically according to user operations. 2) Dynamic content generation allows page content to be adjusted according to conditions. 3) Asynchronous programming ensures that the user interface is not blocked. JavaScript is widely used in web interaction, single-page application and server-side development, greatly improving the flexibility of user experience and cross-platform development.
Who gets paid more Python or JavaScript?
Apr 04, 2025 am 12:09 AM
There is no absolute salary for Python and JavaScript developers, depending on skills and industry needs. 1. Python may be paid more in data science and machine learning. 2. JavaScript has great demand in front-end and full-stack development, and its salary is also considerable. 3. Influencing factors include experience, geographical location, company size and specific skills.
How to merge array elements with the same ID into one object using JavaScript?
Apr 04, 2025 pm 05:09 PM
How to merge array elements with the same ID into one object in JavaScript? When processing data, we often encounter the need to have the same ID...
Is JavaScript hard to learn?
Apr 03, 2025 am 12:20 AM
Learning JavaScript is not difficult, but it is challenging. 1) Understand basic concepts such as variables, data types, functions, etc. 2) Master asynchronous programming and implement it through event loops. 3) Use DOM operations and Promise to handle asynchronous requests. 4) Avoid common mistakes and use debugging techniques. 5) Optimize performance and follow best practices.
How to achieve parallax scrolling and element animation effects, like Shiseido's official website?
or:
How can we achieve the animation effect accompanied by page scrolling like Shiseido's official website?
Apr 04, 2025 pm 05:36 PM
Discussion on the realization of parallax scrolling and element animation effects in this article will explore how to achieve similar to Shiseido official website (https://www.shiseido.co.jp/sb/wonderland/)...
The difference in console.log output result: Why are the two calls different?
Apr 04, 2025 pm 05:12 PM
In-depth discussion of the root causes of the difference in console.log output. This article will analyze the differences in the output results of console.log function in a piece of code and explain the reasons behind it. �...
How to implement panel drag and drop adjustment function similar to VSCode in front-end development?
Apr 04, 2025 pm 02:06 PM
Explore the implementation of panel drag and drop adjustment function similar to VSCode in the front-end. In front-end development, how to implement VSCode similar to VSCode...
