canvas彩色线条旋转交织动画效果代码-html代码-BFW代码库

代码语言：html

所属分类：动画

代码描述：canvas彩色线条旋转交织动画效果代码

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: #000;
  margin: 0;
  padding: 0;
  border-width: 0;
  overflow: hidden;
}
</style>

  
  
  
</head>

<body translate="no">
  
  
      <script >
"use strict";

const LIMIT_FRACT = 5; // in pixels
const DURATION = 1500; // in ms, for each recursion level

let canv, ctx; // canvas and context
let maxx, maxy; // canvas dimensions

// for animation
let messages;
let dragon;
let baseline, basep;
let clear = false;

const b90 = 4 / 3 * (Math.sqrt(2) - 1); // to draw 1/4 circle with Bézier curves

// shortcuts for Math.
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 mPIS3 = Math.PI / 3;
const m2PI = Math.PI * 2;
const m2PIS3 = Math.PI * 2 / 3;
const msin = Math.sin;
const mcos = Math.cos;
const matan2 = Math.atan2;

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

const rac2s2 = msqrt(2) / 2;

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

function alea(mini, maxi) {
  // random number in given range

  if (typeof maxi == "undefined") return mini * mrandom(); // range 0..mini

  return mini + mrandom() * (maxi - mini); // range mini..maxi
}
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
function intAlea(mini, maxi) {
  // random integer in given range (mini..maxi - 1 or 0..mini - 1)
  //
  if (typeof maxi == "undefined") return mfloor(mini * mrandom()); // range 0..mini - 1
  return mini + mfloor(mrandom() * (maxi - mini)); // range mini .. maxi - 1
}

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

function middle(p0, p1) {
  return { x: (p0.x + p1.x) / 2, y: (p0.y + p1.y) / 2 };
} // middle

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

function lerp(p0, p1, alpha) {
  return {
    x: p1.x * alpha + p0.x * (1 - alpha),
    y: p1.y * alpha + p0.y * (1 - alpha) };

} // lerp

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
function Noise1DOneShotModulo(period, modulo, step, random = Math.random) {
  /* returns a 1D single-shot noise generator.
         modulo must be > 0
         the (optional) random function must return a value between 0 and 1
        the returned function has no parameter, and will return a new number every time it is called.
        If the random function provides reproducible values (and is not used elsewhere), this
        one will return reproducible values too.
        period should be > 1. The bigger period is, the smoother output noise is
        All values between 0 and modulo have an equal probablilty. The values wrap from 0 to modulo and vice versa
        This makes the returned function suitable for directions or hues
      */

  let currx = 1 + random() * 0.5; // start with random offset
  let y0;
  let y1 = modulo * random(); // 'previous' value

  const dx = 1 / period;

  return function () {
    currx += dx;
    if (currx > 1) {
      currx -= 1;
      y0 = y1 % modulo;
      y1 = y0 + step * (2 * random() - 1); // 'next' value
      while (y1 < 0) {
        y0 += modulo;
        y1 += modulo;
      }
    }
    let z = (3 - 2 * currx) * currx * currx;
    return (z * y1 + (1 - z) * y0) % modulo;
  };
} // Noise1DOneShotModulo

//------------------------------------------------------------------------
function cutCubicIn2(bezier) {
  const pa = middle(bezier[0], bezier[1]);
  const pb = middle(bezier[1], bezier[2]);
  const pc = middle(bezier[2], bezier[3]);
  const pd = middle(pa, pb);
  const pe = middle(pb, pc);
  const pf = middle(pd, pe);
  return [
  [bezier[0], pa, pd, pf],
  [pf, pe, pc, bezier[3]]];

} // cutCubicIn2

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

function buildDr.........完整代码请登录后点击上方下载按钮下载查看