原生js实现费马canvas动画效果-html代码-BFW代码库

原生js实现费马canvas动画效果

代码语言：html

所属分类：动画

代码描述：原生js实现费马canvas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>
* {
  font-family: 'arial black', Helvetica, verdana, monospace, sans-serif;
  letter-spacing: 0.2rem;
  margin: 0;
  padding: 0;
  color: #FFF;
  overflow: hidden;
}

body {
  position: relative;
}

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

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

<script >
/*
* File Name / fermat.js
* Created Date / July 31, 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 shapes = [];
    var shapeNum = X;
    var angle = 137.5;
    var flg = true;

    if (X < 768) {
      shapeNum = Y;
    }

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

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

    /********************
         Shape
       ********************/

    function Shape(ctx, x, y, i) {
      this.ctx = ctx;
      this.init(x, y, i);
    }

    Shape.prototype.init = function (x, y, i) {
      this.x = x;
      this.y = y;
      this.r = 20 * i / 200;
      this.i = i;
      this.a = this.i / 3;
      this.rad = this.a * Math.PI / 180;
      this.random = Math.random();
    };

    Shape.prototype.draw = function () {
      var ctx = this.ctx;
      ctx.save();
      ctx.globalAlpha = this.random;
      ctx.fillStyle = 'hsl(' + Math.sin(this.rad) * 360 + ', 80%, 60%)';
      ctx.beginPath();
      ctx.arc(
      Math.cos(angle * Math.PI / 180 * this.i) * this.i / 2 + X / 2,
      Math.sin(angle * Math.PI / 180 * this.i) * this.i / 2 + Y / 2,
      Math.sin(this.rad / 2) < 0 ? -Math.sin(this.rad / 2) * this.r : Math.sin(this.rad / 2) * this.r,
      0,
      Math.PI * 2,
      false);

      ctx.fill();
      ctx.restore().........完整代码请登录后点击上方下载按钮下载查看