一款酷炫的动态背景

一款酷炫的动态背景(h5 canvas+js)

废话不多说 ，分享一款酷炫的页面动态背景 效果见下图。

查看 demo

背景图效果：

实例效果

点击效果：

背景css

 *{
        margin: 0;
        padding: 0;
    }
    #canvas{
         position: fixed;
         background: #ccc;
         overflow: auto;
         z-index: -1;
    }

背景html

     <canvas id="canvas"></canvas>

背景js

<script>
    window.requestAnimationFrame = (function(){
        return window.requestAnimationFrame ||
               window.webkitRequestAnimationFrame ||
               window.mozRequestAnimationFrame ||
               function( callback ){
                    window.setTimeout( callback, 1000/2 );
               };
    })();
    var myCanvas = document.getElementById("canvas");
    var ctx = myCanvas.getContext("2d");//getContext 设置画笔
    var num;
    var w,h;
    var duixiang = [];
    var move = {};
    function widthheight(){
        w = myCanvas.width = window.innerWidth;
        h = myCanvas.height = window.innerHeight;
        num= Math.floor(w*h*0.00028);//点的数量。根据屏幕大小确定
        for(var i = 0;i &lt; num;i++){
            duixiang[i] = {
                x:Math.random()*w,
                y:Math.random()*h,
                cX:Math.random()*0.6-0.3,
                cY:Math.random()*0.6-0.3,
                R:Math.floor(Math.random()*5)+2,
                //CC:Math.floor(Math.random()*3)+2,
                r: Math.floor(Math.random() * 254),   
                g: Math.floor(Math.random() * 254),  
                b:Math.floor(Math.random() * 254)   
            } 
           // console.log(duixiang[i])
            Cricle(duixiang[i].x,duixiang[i].y,duixiang[i].R,duixiang[i].r,duixiang[i].g,duixiang[i].b);
             //Cricle(duixiang[i].x,duixiang[i].y,duixiang[i].R,duixiang[i].CC);
        }
    };widthheight();//获取浏览器的等宽度等高

    function Cricle(x,y,R,r,g,b){
        ctx.save();//保存路径
       if(Math.random()&gt;0.991) {ctx.globalAlpha= 0.9;}//ctx.fillStyle = "#CCC";}//填充的背景颜色
        else { ctx.globalAlpha=0.47;}

        ctx.fillStyle = "rgb("+ r +","+ g +","+ b +")";
        ctx.beginPath();//开始绘画
        ctx.arc(x,y,R,Math.PI*2,0);//绘画圆 x y 半径（大小） 角度  一个PI 是180 * 2 = 360    真假 0/1 true/false
        ctx.closePath();//结束绘画
        ctx.fill();//填充背景颜色
        ctx.restore();//回复路径
    };Cricle();


    !function draw(){
        ctx.clearRect(0,0,w,h)//先清除画布上的点
        for(var i = 0;i &lt; num;i++){
            duixiang[i].x += duixiang[i].cX;
            duixiang[i].y += duixiang[i].cY;
            if(duixiang[i].x&gt;w || duixiang[i].x&lt;0){
                duixiang[i].cX = -duixiang[i].cX;
            }
            if(duixiang[i].y&gt;h || duixiang[i].y&lt;0){
                duixiang[i].cY = -duixiang[i].cY;
            }
            Cricle(duixiang[i].x,duixiang[i].y,duixiang[i].R,duixiang[i].r,duixiang[i].g,duixiang[i].b);
            //勾股定理判断两点是否连线
            for(var j = i + 1;j &lt; num;j++){
                if( (duixiang[i].x-duixiang[j].x)*(duixiang[i].x-duixiang[j].x)+(duixiang[i].y-duixiang[j].y)*(duixiang[i].y-duixiang[j].y) &lt;= 55*55 ){
                    line(duixiang[i].x,duixiang[i].y,duixiang[j].x,duixiang[j].y,0,i,j)
                }
                if(move.x){
                    if( (duixiang[i].x-move.x)*(duixiang[i].x-move.x)+(duixiang[i].y-move.y)*(duixiang[i].y-move.y) &lt;= 100*100 ){
                        line(duixiang[i].x,duixiang[i].y,move.x,move.y,1,i,1)
                    }
                }
            }
        }
        window.requestAnimationFrame(draw)
    }();

    //绘制线条
    function line(x1,y1,x2,y2,flag,i,j){

        if (flag){var color = ctx.createLinearGradient(x1,y1,x2,y2);
                    ctx.globalAlpha=0.5;
                    color.addColorStop(0,"rgb("+ duixiang[i].r +","+ duixiang[i].g +","+ duixiang[i].b +")");
                    color.addColorStop(0.8,"#019ee5");
                }
                else
                {

                var color = ctx.createLinearGradient(x1,y1,x2,y2);
                    ctx.globalAlpha=0.9;
                    color.addColorStop(0,"rgb("+ duixiang[i].r +","+ duixiang[i].g +","+ duixiang[i].b +")");
                    color.addColorStop(1,"rgb("+ duixiang[j].r +","+ duixiang[j].g +","+ duixiang[j].b +")");
                }
        ctx.save();
        ctx.strokeStyle = color;
        ctx.lineWidth = 0.5;
        ctx.beginPath();
        ctx.moveTo(x1,y1);
        ctx.lineTo(x2,y2);
        ctx.stroke();
        //ctx.restore();
    }


    //document.onmousemove = function(e){
     //   move.x = e.clientX;
      //  move.y = e.clientY;
    //}
    //console.log(move)//去掉注释 ，可以与背景互动

    window.onresize = function(){
        location.reload();
    }
&lt;/script&gt;

点击效果CSS

#canvas1 {
 position: fixed;
 pointer-events:none;//鼠标多层响应事件
        width: 100%;
        height: 100%;
        overflow: auto;
         z-index: 999;

    }

点击效果HTML

  <canvas id="canvas1" style="whdth: 100%;height: 100%"></canvas>

点击效果js

<script>
var _createClass = function () {function defineProperties(target, props) 
{ for (var i = 0; i &lt; props.length; i++) 
 {var descriptor = props[i];descriptor.enumerable = descriptor.enumerable || false;descriptor.configurable = true;if ("value" in descriptor) 
 descriptor.writable = true;Object.defineProperty(target, descriptor.key, descriptor);}}
 return function (Constructor, protoProps, staticProps) 
 {if (protoProps) defineProperties(Constructor.prototype, protoProps);
 if (staticProps) defineProperties(Constructor, staticProps);
 return Constructor;};}();function _classCallCheck(instance, Constructor) 
 {if (!(instance instanceof Constructor)) {throw new TypeError("Cannot call a class as a function");}}
 var getRandom = function getRandom(min, max) {
  return Math.random() * (max - min) + min;
};

var getRandomInt = function getRandomInt(min, max) {
  return Math.floor(Math.random() * (max - min)) + min;
};
var getRandomColor = function getRandomColor() {
  var colors = [
  ‘rgba(231, 76, 60, 1)’, // red
  ‘rgba(241, 196, 15, 1)’, // yellow
  ‘rgba(46, 204, 113, 1)’, // green
  ‘rgba(52, 152, 219, 1)’, // blue
  ‘rgba(155, 89, 182, 1)’ // purple
  ];
  return colors[getRandomInt(0, colors.length)];
};
// Particle//粒子模块
var
Particle = function () {
  function Particle(system, x, y) {_classCallCheck(this, Particle);
    this.system = system;
    this.universe = this.system.world.universe;
    this.x = x;
    this.y = y;
    this.color = getRandomColor();
    this.life = 1;
    this.aging = getRandom(0.990, 0.999); // 0.99, 0.999 || 0.999, 0.9999
    this.r = getRandomInt(12, 16);//初始粒子半径范围
    this.speed = getRandom(18, 18.5);//粒子爆炸速度范围
    this.velocity = [
    getRandom(-this.speed, this.speed),
    getRandom(-this.speed, this.speed)];
  }_createClass(Particle, [{ key: ‘update’, value: function update(
    dt) {
      this.life *= this.aging;
      if (
      this.r &lt; 0.1 ||
      this.life === 0 ||
      this.x + this.r &lt; 0 ||
      this.x - this.r &gt; this.universe.width ||
      this.y + this.r &lt; 0 ||
      this.y - this.r &gt; this.universe.height)
      {
        this.system.removeObject(this);
      }
      this.r *= this.life;
      this.x += this.velocity[0];
      this.y += this.velocity[1];
    } }, { key: ‘render’, value: function render(
    ctx) {
      // Main circle //亮圈模块
      ctx.fillStyle = this.color;
      ctx.beginPath();
      ctx.arc(this.x, this.y, this.r*1.2, 0, 2 * Math.PI, false);
      ctx.fill();
      ctx.closePath();
      var r = this.color.match(/([0-9]+)/g)[0];
      var g = this.color.match(/([0-9]+)/g)[1];
      var b = this.color.match(/([0-9]+)/g)[2];
      // Gradient//梯度变化曲线
      var spread = 1.5;
      var gradient = ctx.createRadialGradient(
      this.x, this.y, this.r,
      this.x, this.y, this.r * spread);
      gradient.addColorStop(0, ‘rgba(‘ + r + ‘, ‘ + g + ‘, ‘ + b + ‘, 0.5)’);
      gradient.addColorStop(1, ‘rgba(‘ + r + ‘, ‘ + g + ‘, ‘ + b + ‘, 0)’);
      ctx.globalCompositeOperation = ‘lighter’;
      ctx.fillStyle = gradient;
      ctx.beginPath();
      ctx.arc(this.x, this.y, this.r * spread, 0, 2 * Math.PI, false);
      ctx.fill();
      ctx.closePath();
      ctx.globalCompositeOperation = ‘source-over’;
      // Aberration//偏差
      var offset = this.r * 0.5;
      var color = ‘rgba(‘ + g + ‘, ‘ + b + ‘, ‘ + r + ‘, 0.5)’;
      ctx.globalCompositeOperation = ‘lighter’;
      ctx.fillStyle = color;
      ctx.beginPath();
      ctx.arc(this.x + offset, this.y + offset, this.r, 0, 2 * Math.PI, false);
      ctx.fill();
      ctx.closePath();
      ctx.globalCompositeOperation = ‘source-over’;
    } }]);return Particle;}();
// Crown //水波纹圈模块
var
Crown = function () {
  function Crown(system, x, y) {_classCallCheck(this, Crown);
    this.system = system;
    this.x = x;
    this.y = y;
    this.r = getRandomInt(5, 15); // 5, 20  水波纹圈半径范围
    this.mod = 1.1;
    this.life = 0.5; //水波纹线
    this.aging = getRandom(0.830, 0.899);
    this.speed = getRandom(8, 9);
    this.color = {
      r: getRandomInt(236, 242),
      g: getRandomInt(70, 80),
      b: getRandomInt(50, 70) };
    this.angle1 = Math.PI * getRandom(0, 2);
    this.angle2 = this.angle1 + Math.PI * getRandom(0.3, 0.4);//水波纹圈完整度
  }_createClass(Crown, [{ key: ‘update’, value: function update(
    dt) {
      this.life *= this.aging;
      if (this.life &lt;= 0.0001) this.system.removeObject(this);
      this.r += Math.abs(1 - this.life) * this.speed;
      this.x1 = this.x + this.r * Math.cos(this.angle1);
      this.y1 = this.y + this.r * Math.sin(this.angle1);
      this.angle3 = this.angle1 + (this.angle2 - this.angle1) / 2;
      this.x2 = this.x + this.r * this.mod * Math.cos(this.angle3);
      this.y2 = this.y + this.r * this.mod * Math.sin(this.angle3);
    } }, { key: ‘render’, value: function render(
    ctx) {
      var gradient = ctx.createRadialGradient(
      this.x, this.y, this.r * 0.9,
      this.x, this.y, this.r);
      gradient.addColorStop(0, ‘rgba(‘ + this.color.r + ‘, ‘ + this.color.g + ‘, ‘ + this.color.b + ‘, ‘ + this.life + ‘)’);
      gradient.addColorStop(1, ‘rgba(‘ + this.color.r + ‘, ‘ + this.color.g + ‘, ‘ + this.color.b + ‘, ‘ + this.life * 0.5 + ‘)’);
      ctx.fillStyle = gradient;
      ctx.beginPath();
      ctx.arc(this.x, this.y, this.r, this.angle1, this.angle2, false);
      ctx.quadraticCurveTo(this.x2, this.y2, this.x1, this.y1);
      ctx.fill();
      ctx.closePath();
    } }]);return Crown;}();
// Explosion //爆炸模块
var
Explosion = function () {
  function Explosion(world, x, y) {_classCallCheck(this, Explosion);
    this.world = world;
    this.x = x;
    this.y = y;
    this.objects = [];
    var particles = getRandomInt(10, 30); // 10, 30 amount of particles//爆炸 粒子数量
    var crowns = particles * getRandom(0.4, 0.5);
    while (crowns– &gt; 0) {this.addCrown();}
    while (particles– &gt; 0) {this.addParticle();}
  }_createClass(Explosion, [{ key: ‘update’, value: function update(
    dt) {
      this.objects.forEach(function (obj) {
        if (obj) obj.update(dt);
      });
      if (this.objects.length &lt;= 0) {
        this.world.clearExplosion(this);
      }
    } }, { key: ‘render’, value: function render(
    ctx) {
      this.objects.forEach(function (obj) {
        if (obj) obj.render(ctx);
      });
    } }, { key: ‘addCrown’, value: function addCrown()
    {
      this.objects.push(new Crown(this, this.x, this.y));
    } }, { key: ‘addParticle’, value: function addParticle()
    {
      this.objects.push(new Particle(this, this.x, this.y));
    } }, { key: ‘removeObject’, value: function removeObject(
    obj) {
      var index = this.objects.indexOf(obj);
      if (index !== -1) {
        this.objects.splice(index, 1);
      }
    } }]);return Explosion;}();
// World 
var
ConfettiWorld = function () {function ConfettiWorld()
{_classCallCheck(this, ConfettiWorld);}_createClass(ConfettiWorld, [{ key: ‘init’, value: function init()
    {
      this.objects = [];
      window.addEventListener(‘click’, this.explode.bind(this));
      // Initial explosion //初始爆炸
      var counter = 0;
      while (counter– &gt; 0) {
        this.explode({
          clientX: window.event.clientX, //getRandomInt(10, this.universe.width) ,          //this.universe.width / 2,
          clientY: window.event.clientY //getRandomInt(10, 50) //this.universe.height / 2 
          });
      }
    } }, { key: ‘update’, value: function update(
    dt) {
      this.objects.forEach(function (obj) {
        if (obj) obj.update(dt);
      });
      var amount = this.objects.reduce(function (sum, explosion) {
        return sum += explosion.objects.length;
      }, 0);
    } }, { key: ‘render’, value: function render(
    ctx) {
      this.objects.forEach(function (obj) {
        if (obj) obj.render(ctx);
      });
    } }, { key: ‘explode’, value: function explode(
    event) {
      var x = event.clientX;
      var y = event.clientY;
      this.objects.push(new Explosion(this, x, y));
    } }, { key: ‘clearExplosion’, value: function clearExplosion(
    explosion) {
      var index = this.objects.indexOf(explosion);
      if (index !== -1) {
        this.objects.splice(index, 1);
      }
    } }]);return ConfettiWorld;}();
// Time
var
Time = function () {
  function Time() {_classCallCheck(this, Time);
    this.now = 0; // current tick time
    this.prev = 0; // prev tick time
    this.elapsed = 0; // elapsed time from last tick
    this.delta = 0; // time from last update
    this.fps = 60; // desired fps
    this.step = 1 / 60; // step duration
  }_createClass(Time, [{ key: ‘update’, value: function update(
    time) {
      this.now = time;
      this.elapsed = (this.now - this.prev) / 1000;
      this.prev = this.now;
      this.delta += this.elapsed;
    } }, { key: ‘raf’, value: function raf(
    func) {
      window.requestAnimationFrame(func);
    } }, { key: ‘hasFrames’, value: function hasFrames()
    {
      return this.delta &gt;= this.step;
    } }, { key: ‘processFrame’, value: function processFrame()
    {
      this.delta -= this.step;
    } }]);return Time;}();
// Canvas
var
Universe = function () {
  function Universe(element) {_classCallCheck(this, Universe);
    this.el = element;
    this.ctx = this.el.getContext(‘2d’);
    this.pixelRatio = window.devicePixelRatio;
    this.time = new Time();
    this.worlds = {};
    this.world = null; // current state
    this.updateSize();
    window.addEventListener(‘resize’, this.updateSize.bind(this));
    this.addWorld(‘confetti’, ConfettiWorld);
    this.setWorld(‘confetti’);
    this.start();
  }_createClass(Universe, [{ key: ‘start’, value: function start()
    {
      this.time.raf(this.tick.bind(this));
    } }, { key: ‘tick’, value: function tick(
    time) {
      this.time.update(time);
      if (this.time.hasFrames()) {
        this.update();
        this.time.processFrame();
      }
      this.render();
      this.time.raf(this.tick.bind(this));
    } }, { key: ‘update’, value: function update()
    {
      this.world.update(this.time.step);
    } }, { key: ‘render’, value: function render()
    {
      var gradient = this.ctx.createLinearGradient(0, 0, this.width, this.height);
      this.ctx.clearRect(0, 0, this.width, this.height);
      this.world.render(this.ctx);
    }
<span class="token comment" spellcheck="true">// Helpers 库</span>
  }, { key: ‘updateSize’, value: function updateSize()
    {
      this.width = window.innerWidth;
      this.height = window.innerHeight;
      this.el.width = this.width * this.pixelRatio;
      this.el.height = this.height * this.pixelRatio;
      this.el.style.width = window.innerWidth + ‘px’;
      this.el.style.height = window.innerHeight + ‘px’;
      this.ctx.scale(this.pixelRatio, this.pixelRatio);
    } }, { key: ‘addWorld’, value: function addWorld(
    worldName, World) {
      this.worlds[worldName] = new World();
      this.worlds[worldName].universe = this;
      this.worlds[worldName].init();
    } }, { key: ‘setWorld’, value: function setWorld(
    worldName) {
      this.world = this.worlds[worldName];
    } }]);return Universe;}();
// Main
console.clear();
var element = document.querySelector(‘#canvas1’);
window.Canvas= new Universe(element);
</script>