原生js实现canvas群粒子动画效果-html代码-BFW代码库

原生js实现canvas群粒子动画效果

代码语言：html

所属分类：粒子

代码描述：原生js实现canvas群粒子动画效果

下面为部分代码预览，完整代码请点击下载或在bfwstudio webide中打开

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">

<style>
* {
  margin: 0;
  padding: 0;
}

canvas#canvas {
  display: block;
  background: #000;
}
</style>

</head>
<body translate="no">
<canvas id="canvas">Canvas not supported.</canvas>

<script >
(function () {
  'use strict';
  window.addEventListener('load', function () {
    var canvas = document.getElementById('canvas');

    if (!canvas || !canvas.getContext) {
      return false;
    }

    /********************
        Random Number
      ********************/

    function rand(min, max) {
      return Math.floor(Math.random() * (max - min + 1) + min);
    }

    /********************
        Var
      ********************/

    // canvas 
    var ctx = canvas.getContext('2d');
    var X = canvas.width = window.innerWidth;
    var Y = canvas.height = window.innerHeight;
    var mouseX = X / 2;
    var mouseY = Y / 2;

    /********************
                          Animation
                        ********************/

    window.requestAnimationFrame =
    window.requestAnimationFrame ||
    window.mozRequestAnimationFrame ||
    window.webkitRequestAnimationFrame ||
    window.msRequestAnimationFrame ||
    function (cb) {
      setTimeout(cb, 17);
    };

    /********************
         Pug
       ********************/

    var pugNum = 500;
    var pugs = [];

    function Pug(ctx, x, y, h) {
      this.ctx = ctx;
      this.init(x, y, h);
    }

    Pug.prototype.init = function (x, y, h) {
      this.x = x;
      this.y = y;
      this.h = h;
      this.h === true ? this.r = 1 : this.r = 1;
      this.l = rand(5, 10);
      this.a = rand(0, 360);
      this.rad = this.a * Math.PI / 180;
      this.c = {
        r: rand(0, 255),
        g: rand(0, 100),
        b: rand(0, 255) };

      this.v = {
        x: rand(-5, 5) * Math.random() + 1,
        y: rand(-5, 5) * Math.random() + 1,
        z: Math.random() * 3 };

    };


    Pug.prototype.draw = function () {
      var ctx = this.ctx;
      ctx.save();
      ctx.globalCompositeOperation = 'lighter';
      ctx.fillStyle = 'rgb(' + this.c.r + ', ' + this.c.g + ', ' + this.c.b + ')';
      ctx.beginPath();
      ctx.arc(this.x, this.y, this.r, 0, Math.PI * 2, false);
      ctx.fill();
      ctx.restore();
    };

    Pug.prototype.updatePosition = function () {
      this.x += Math.cos(this.rad) * 3 + this.v.x;
      this.y += Math.sin(this.rad) * 3 + this.v.y;
    };

    Pug.prototype.wrapPosition = function () {
      if (this.x < 0 - 200) this.x = X;
      if (this.x > X + 200) this.x = 0;
      if (this.y < 0 - 200) this.y = Y;
      if (this.y > Y + 200) this.y = 0;
    };

    Pug.prototype.closestPug = function (i) {
      var j = i;
      var dist = Number.MAX_VALUE;
      var closestI = 0;
      for (var i = 0; i < pugs.length; i++) {
        if (j !== i && pugs[i].h === true) {
          var x = Math.abs(this.x - pugs[i].x);
          var y = Math.abs(this.y - pugs[i].y);
          var d = x * x + y * y;
      .........完整代码请登录后点击上方下载按钮下载查看