canvas实现聚烯烃动画效果代码-html代码-BFW代码库

代码语言：html

所属分类：动画

代码描述：canvas实现聚烯烃动画效果代码

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">

  
  
  
  
<style>
body {
  font-family: Arial, Helvetica, "Liberation Sans", FreeSans, sans-serif;
  background-color: #ffe;
  margin:0;
  padding:0;
  border-width:0;
  overflow:hidden;
}

canvas {
    position: absolute;
    top: 0;
    left: 0;
}

div {
    position: absolute;
    top: 0;
    left: 0;
    width : 100vw;
    height: 100vh;
    transition: background-color 1.5s linear;
}
</style>


</head>

<body  >


  
      <script >
"use strict";
/* Author : Claude Chauvet (https://codepen.io/Dillo)
/* very much inspired by mandala vı https://codepen.io/smlsvnssn/pen/VQwyJN by smlsvnssn (@smlsvnssn) */

window.addEventListener("load", function () {

  const mrandom = Math.random;
  const mfloor = Math.floor;
  const mround = Math.round;
  const mceil = Math.ceil;
  const mabs = Math.abs;
  const mmin = Math.min;
  const mmax = Math.max;

  const mPI = Math.PI;
  const mPIS2 = Math.PI / 2;
  const m2PI = Math.PI * 2;
  const msin = Math.sin;
  const mcos = Math.cos;
  const matan2 = Math.atan2;

  const mhypot = Math.hypot;
  const msqrt = Math.sqrt;

  let maxx, maxy;
  let repeat, nbPoly, polyodous;
  let tx, ty; // tables of cosines / sines
  let withBlur;

  /*	============================================================================
  	This hash function is based upon Johannes Baagoe's carefully designed and efficient hash
  	function for use with JavaScript.  It has a proven "avalanche" effect such
  	that every bit of the input affects every bit of the output 50% of the time,
  	which is good.	See: http://baagoe.com/en/RandomMusings/hash/avalanche.xhtml
  	============================================================================
  */
  /* This function returns a hash function depending on a seed.
  
  if no seed is provided (or a falsy value), Math.random() is used.
  The returned function always returns the same number in the range [0..1[ for the
  same value of the argument. This argument may be a String or a Number or anything else
  which can be 'toStringed'
  Two returned functions obtained with two equal seeds are equivalent.
  */

  function hashFunction(seed) {
    let n0 = 0xefc8249d;
    let n = n0;
    mash(seed || Math.random()); // pre-compute n for seed
    n0 = n; //

    function mash(data) {
      data = data.toString() + 'U';
      n = n0;
      for (let i = 0; i < data.length; i++) {
        n += data.charCodeAt(i);
        var h = 0.02519603282416938 * n;
        n = h >>> 0;
        h -= n;
        h *= n;
        n = h >>> 0;
        h -= n;
        n += h * 0x100000000; // 2^32
      } // for
      return (n >>> 0) * 2.3283064365386963e-10; // 2^-32
    } // mash
    return mash;
  } // hashFunction(seed)
  // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

  function alea(min, max) {
    // random number [min..max[ . If no max is provided, [0..min[

    if (typeof max == 'undefined') return min * mrandom();
    return min + (max - min) * mrandom();
  }

  // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

  function intAlea(min, max) {
    // random integer number [min..max[ . If no max is provided, [0..min[

    if (typeof max == 'undefined') {
      max = min;min = 0;
    }
    return mfloor(min + (max - min) * mrandom());
  } // intAlea

  // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

  function Noise1D(period, min = 0, max = 1, hash) {
    /* returns a 1D noise function.
       the (mandatory) hash function must return a value between 0 and 1. The hash function
       will be called with an integer number for a parameter.
      the returned function takes one parameter, and will always return the same value if called with the same parameter
      period should be > 1. The bigger period is, the smoother the output noise is
    
    suggestion : the hash parameter could be a function returned from a call to hashFunction above
    
    */

    let currx, y0, y1; // cached valued, to reduce number of calls to 'hash'
    let phase = hash(0); // to shift the phase of different generators between each other;

    return function (x) {
      let xx = x / period + phase;
      let intx = mfloor(xx);

      if (intx - 1 === currx) {// next integer interval
        ++currx;
        y0 = y1;
        y1 = min + (max - min) * hash(currx + 1);
      } else if (intx !== currx) {// unrelated interval
        currx = intx;
        y0 = min + (max - min) * hash(currx);
        y1 = min + (max - min) * hash(currx + 1);
      }
      let frac = xx - currx;
      let z = (3 - 2 * frac) * frac * frac;
      return z * y1 + (1 - z) * y0;
    };
  } // Noise1D

  //---------------------------------------------------------------------
  class Polyodous {

    constructor(radius, repeat) {
      this.r1 = radius;
      this.genr2 = Noise1D(intAlea(4000, 6000), 0.316, 0.95, hashFunction()); // will be squares => 0.1 to 0.9
      this.repeat = repeat;
      this.style = [0, 0, 1, 1, 2, 3][intAlea(6)]; // 0: lines, 1: Bézier quadratic, 2: Bézier cubic, 3: other Bézier quadratic
      this.ang0 = intAlea(2); // for a random half-period shift
      this.color = `hsl(${intAlea(360)}, ${[50, 75, 100, 100][intAlea(4)]}%, ${intAlea(40, 60)}%)`;
      this.x = [];
      this.y = [];
      for (let k = 0; k <= repeat; ++k) {
        this.x[k] = this.r1 * tx[2 * k + this.ang0] + maxx / 2;
        this.y[k] = this.r1 * ty[2 * k + this.ang0] + maxy / 2;
      }
      if (this.style == 2) {
        this.xc1 = [];
        this.yc1 = [];
        this.xc2 = [];
        this.yc2 = [];
        let l = this.r1 * m2PI / repeat / 3; // length of bezier controls at tips
        for (let k = 0; k <= repeat + 1; ++k) {
          this.xc1[k] = this.x[k] + l * ty[2 * k + this.ang0];
          this.yc1[k] = this.y[k] - l * tx[2 * k + this.ang0];
          this.xc2[k] = this.x[k] - l * ty[2 * k + this.ang0];
          this.yc2[k] = this.y[k] + l * tx[2 * k + this.ang0];
        }

      }
    } // constru.........完整代码请登录后点击上方下载按钮下载查看