canvas立体层次效果圆形背景效果-html代码-BFW代码库

canvas立体层次效果圆形背景效果

代码语言：html

所属分类：背景

代码描述：canvas立体层次效果圆形背景效果

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>
body, html {
  margin: 0;
}

canvas {
  display: block;
  cursor: pointer; 
}
</style>

</head>
<body translate="no">
<canvas id="canvas"></canvas>

<script >
/*
  Johan Karlsson, 2020
  https://twitter.com/DonKarlssonSan
  MIT License, see Details View
*/
let canvas;
let ctx;
let w, h;

function setup() {
  canvas = document.querySelector("#canvas");
  ctx = canvas.getContext("2d");
  resize();
  window.addEventListener("resize", () => {
    resize();
    draw();
  });
  canvas.addEventListener("click", draw);
}

function resize() {
  w = canvas.width = window.innerWidth;
  h = canvas.height = window.innerHeight;
}

function draw() {
  ctx.fillRect(0, 0, w, h);
  ctx.strokeStyle = "white";
  ctx.shadowColor = "black";
  ctx.shadowOffsetX = 8;
  ctx.shadowOffsetY = 8;
  ctx.shadowBlur = 20;
  let size = Math.random() * 80 + 20;
  let positions = getPositions(size);
  drawRects(positions, size);
}

function getPositions(size) {
  let positions = [];
  positions.push({
    x: w / 2,
    y: h / 2,
    color: "hsl(220, 60%, 50%)",
    angle: 0
  });
  let randomAngleOffset = Math.random() * 360;
  let nrOfCircles = Math.max(w, h) * 0.7 / size;
  for(let circle = 0; circle < nrOfCircles; circle++) {
    let r = (circle + 1) * size;
    let points = r * 8 / size;
    let deltaAngle = Math.PI * 2 / points;
    let offsetAngle = Math.random() * Math.PI;
    for(let angle = 0; angle < Math.PI * 2; angle += deltaAngle) {
      let hue = angle / Math.PI / 2 * 360 + randomAngleOffset;
      let l = Math.random() * 40 + 30;
      let color = `hsl(${hue}.........完整代码请登录后点击上方下载按钮下载查看