原生js实现炫酷星光动画效果-html代码-BFW代码库

原生js实现炫酷星光动画效果

代码语言：html

所属分类：粒子

代码描述：原生js实现炫酷星光动画效果

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;
  overflow: hidden;
}

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

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

<script>
/*
* File Name / starlightEffect.js
* Created Date / Aug 18, 2020
* Aurhor / Toshiya Marukubo
* Twitter / https://twitter.com/toshiyamarukubo
*/

(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
      ********************/

    var ctx = canvas.getContext('2d');
    var X = canvas.width = window.innerWidth;
    var Y = canvas.height = window.innerHeight;
    var mouseX = null;
    var mouseY = null;
    var pointX = X / 2;
    var pointY = 0;
    // spark
    var rad = Math.PI * 2 / 8;
    var sparks = [];
    var sparkNum = 500;
    var radius = 1;
    var time = 0;
    var color = 'hsl(' + Math.sin(time * Math.PI / 180) * 360 + ', 80%, 60%)';

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

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

    /********************
         Spark
       ********************/

    function Spark(ctx, x, y, cl) {
      this.ctx = ctx;
      this.init(x, y, cl);
    }

    Spark.prototype.init = function (x, y, cl) {
      this.x = x;
      this.y = y;
      this.cl = cl;
      this.lw = 1;
      this.r = rand(5, 30);
      Math.random() < 0.8 ? this.l = rand(0, 50) : this.l = rand(100, 150);
      this.sl = this.l;
      this.ga = Math.random() * Math.random();
      this.v = {
        x: Math.cos(rand(0, 360) * Math.PI / 180) * Math.random() * 2,
        y: Math.sin(rand(0, 360) * Math.PI / 180) * Math.random() * 2 };

    };

    Spark.prototype.draw = function () {
      var ctx = this.ctx;
      ctx.save();
      ctx.lineWidth = this.lw;
      ctx.globalAlpha = this.ga;
      ctx.globalCompositeOperation = 'lighter';
      ctx.strokeStyle = color;
      for (var i = 1; i < 9; i++) {
        ctx.beginPath();
        ctx.moveTo(this.x, this.y);
        ctx.lineTo(Math.cos(rad * i) * this.r + this.x, Math.sin(rad * i) * this.r + this.y);
        ctx.stroke();
      }
      ctx.restore();
    };

    Spark.prototype.updateParams = function (i) {
      // life
      this.l -= 1;
      if (this.l < 0) {
        this.cl++;
        this.init(pointX, pointY, this.cl);
      }
    };

    Spark.prototype.updatePosition = function () {
      this.x += this.v.x;
      this.y += this.v.y;
    };

    Spark.prototype.render = function (i) {
      this.updateParams(i);
      this.updatePosition();
      this.draw();
    };

    for (var i = 0; i < sparkNum; i++) {
      var s = new Spark(ctx, pointX, pointY, 0);
      sparks.push(s);
    }

    /********************
        Move
      ********************/

    function firstMotion() {
      pointY += 2;
    }

    function secondMotion() {
      pointX = Math.cos(time) * radius + X / 2;
      pointY = Math.sin(time) * radius + Y / 2;
      radius += 1;
    }

    function thirdMotion() {
      pointX = Math.cos(time) * radius + X / 2;
      pointY = Math.sin(time) * radius + Y / 2;
      radius -= 1;
    }

    function fourthMotion() {
      pointX = Math.sin(time) * X / 2 + X / 2;
      pointY = Y / 2;
    }

    function fifthMotion() {
      pointY = Math.sin(time) * radius + Y / 2;
      pointX += 5;
      radius += 1;
    }

    function lastMotion() {
      for (var i = 0; i < sparks.length; i++) {
        sparks[i].x = rand(0, X).........完整代码请登录后点击上方下载按钮下载查看