canvas实现圈圈扩散动画效果代码-html代码-BFW代码库

canvas实现圈圈扩散动画效果代码

代码语言：html

所属分类：动画

代码描述：canvas实现圈圈扩散动画效果代码

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">
  

  
</head>

<body translate="no">
  
  
      <script >
"use strict"; // Paul Slaymaker, paul25882@gmail.com
const body = document.getElementsByTagName("body").item(0);
body.style.background = "#000";
const TP = 2 * Math.PI;
const CSIZE = 400;

const ctx = (() => {
  let d = document.createElement("div");
  d.style.textAlign = "center";
  body.append(d);
  let c = document.createElement("canvas");
  c.width = c.height = 2 * CSIZE;
  d.append(c);
  return c.getContext("2d");
})();
ctx.translate(CSIZE, CSIZE);

const ctxo = (() => {
  let c = document.createElement("canvas");
  c.width = c.height = CSIZE;
  return c.getContext("2d", { "willReadFrequently": true });
})();

onresize = () => {
  let D = Math.min(window.innerWidth, window.innerHeight) - 40;
  ctx.canvas.style.width = ctx.canvas.style.height = D + "px";
};

const getRandomInt = (min, max, low) => {
  if (low) return Math.floor(Math.random() * Math.random() * (max - min)) + min;else
  return Math.floor(Math.random() * (max - min)) + min;
};

function Color() {
  const CBASE = 144;
  const CT = 255 - CBASE;
  this.getRGB = c => {
    let red = Math.round(CBASE + CT * Math.cos(this.RK2 + c / this.RK1));
    let grn = Math.round(CBASE + CT * Math.cos(this.GK2 + c / this.GK1));
    let blu = Math.round(CBASE + CT * Math.cos(this.BK2 + c / this.BK1));
    return "rgb(" + red + "," + grn + "," + blu + ")";
  };
  this.randomize = () => {
    this.RK1 = 20 + 20 * Math.random();
    this.GK1 = 20 + 20 * Math.random();
    this.BK1 = 20 + 20 * Math.random();
    this.RK2 = TP * Math.random();
    this.GK2 = TP * Math.random();
    this.BK2 = TP * Math.random();
  };
  this.randomize();
}

var color = new Color();

var stopped = true;
var start = () => {
  if (stopped) {
    stopped = false;
    requestAnimationFrame(animate);
  } else {
    stopped = true;
  }
};
body.addEventListener("click", start, false);

var t = 0;
const DUR = 800;
var animate = ts => {
  if (stopped) return;
  t++;
  draw();
  //if (EM && tt%200==0) stopped=true;
  requestAnimationFrame(animate);
};

var Circle = function (x, y) {
  this.x = x;
  this.y = y;
  this.K1x = TP * Math.random();
  this.K2x = 200 + 200 * Math.random();
  this.K1y = TP * Math.random();
  this.K2y = 200 + 200 * Mat.........完整代码请登录后点击上方下载按钮下载查看