canvas立体多彩水滴落下动画效果代码-html代码-BFW代码库

canvas立体多彩水滴落下动画效果代码

代码语言：html

所属分类：动画

代码描述：canvas立体多彩水滴落下动画效果代码

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;
  cursor: pointer;
}
</style>


  
  
</head>

<body>
  
  
      <script  >
"use strict";

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

// for animation
let messages;

// 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;

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

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
}

//------------------------------------------------------------------------
class Drop {
  constructor(Ysize) {
    this.Ysize = Ysize;
    this.createPath();
    const duration = 300;
    this.speed = Ysize / duration; // will move its own length in this number of ms
    this.start(performance.now());
    this.Ypos = alea(maxy); // random initial position
  }

  start(t) {
    this.Xaxis = alea(maxx);
    this.tInit = t;
    this.Ypos = -this.Ysize - 1; // initial position
  }

  createPath() {
    const alpha = mPI / 6;
    const c = mcos(alpha);
    const s = msin(alpha);

    const path = this.path = new Path2D();
    const r = 0.2 * this.Ysize;
    const lc = this.Ysize - r;
    const l0 = 0.4 * lc;
    const l1 = 0.1 * lc;
    const x1 = r * c;
    const y1 = lc - r * s;
    const bx1 = x1 - l1 * s;
    const by1 = y1 - l1 * c;

    path.moveTo(0, 0);
    path.bezierCurveTo(0, l0, bx1, by1, x1, y1);
    path.arc(0, lc, r, -alpha, mPI + alpha);
    path.bezierCurveTo(-bx1, by1, 0, l0, 0, 0);
    path.closePath();

    const gr = this.gr = ctx.createLinearGradient(-r, 0, +r, 0);
    const hue = intAlea(360);
    const sat = alea(40, 100);
    gr.addColorStop(0, `hsl(${hue} ${sat}% 30%)`);
    gr.addColorStop(0.5, `hsl(${hue} ${sat}% 50%)`);
    gr.addColorStop(1, `hsl(${hue} ${sat}% 70%)`);
  } // Drop.createPath

  draw() {
    ctx.save();
    ctx.translate(this.X.........完整代码请登录后点击上方下载按钮下载查看