canvas实现可交互彩带效果代码-html代码-BFW代码库

canvas实现可交互彩带效果代码

代码语言：html

所属分类：其他

代码描述：canvas实现可交互彩带效果代码

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;
  /*  cursor: pointer; */
}
</style>

  
  
  
</head>

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

const NB_NODES_HORIZ_MIN = 4;
const NB_NODES_HORIZ_MAX = 8;
const AMPLITUDE_HORIZ = 0.4;
const AMPLITUDE_VERT = 0.4; // node will move +/- this number * the vertical distance between nodes
const PERIOD_HORIZ = 300; // pseudo-period (in frames) of horizontal movement
const PERIOD_VERT = 1000; // pseudo-period (in frames) of vertical movement

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

// for animation
let messages;
let points;
let nbNodesX, nbNodesY;
let distX, distY; // between nodes
let nbSubdiv;
let colors;
let drawMode = 0;
let bg = true;

// 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 rac3 = msqrt(3);
const rac3s2 = rac3 / 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 Noise1DOneShot(period, min = 0, max = 1, random) {
  /* returns a 1D single-shot noise generator.
               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 reproductible 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
            */
  random = random || Math.random;
  let currx = random(); // start with random offset
  let y0 = min + (max - min) * random(); // 'previous' value
  let y1 = min + (max - min) * random(); // 'next' value
  let dx = 1 / period;
  const dx0 = 0.667 * dx;
  const dx1 = 1.333 * dx;
  dx = dx0 + (dx1 - dx0) * random();
  return function () {
    currx += dx;
    if (currx > 1) {
      currx -= 1;
      y0 = y1;
      y1 = min + (max - min) * random();
      dx = dx0 + (dx1 - dx0) * random(); // change "period" every ... period
    }
    let z = (3 - 2 * currx) * currx * currx;
    return z * y1 + (1 - z) * y0;
  };
} // Noise1DOneShot

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