canvas线条跟随引力绘图动画效果代码-html代码-BFW代码库

canvas线条跟随引力绘图动画效果代码

代码语言：html

所属分类：动画

代码描述：canvas线条跟随引力绘图动画效果代码，小球越大引力越大，线条就会朝它过去。

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 {
  height: 100vh;
  margin: 0;
  overflow: hidden;
  display: grid;
  place-items: center;
}

#frame-count {
  position: absolute;
  bottom: 0;
  right: 0;
  display: none;
}

canvas {
  width: clamp(200px, 80vmin, 600px);
  height: clamp(200px, 80vmin, 600px);
}
</style>

  
</head>

<body>
  <canvas></canvas>
<div id="frame-count">0</div>
 
  
      <script  >
const { cos, sin, pow, atan2, min, max, PI: π } = Math;
const query = document.querySelector.bind(document);
const canvas = query('canvas');
const ctx = canvas.getContext('2d');

const Physics = {
  G: 6.7 * 10 };


const setup = () => {
  const width = 600;
  const height = 600;
  canvas.width = width;
  canvas.height = height;
  ctx.fillStyle = 'white';
  ctx.fillRect(0, 0, width, height);
  return {
    width,
    height };

};

const { width, height } = setup();

const Marker = {
  // Not confident about physics terminology
  init({ x, y, mass, radius, style, velocity, angle }) {
    this.x = x;
    this.y = y;
    this.mass = mass;
    this.radius = radius;
    this.style = style;
    this.velocity = velocity;
    this.angle = angle;
    this.momentX = this.velocity * cos(this.angle);
    this.momentY = this.velocity * sin(this.angle);
    this.velocityX = this.momentX;
    this.velocityY = this.momentY;
    this.trail = [{
      x: this.x,
      y: this.y }];

  },

  gravitateTo(attractor) {
    const force =
    Physics.G *
    this.mass *
    attractor.mass / (
    pow(attractor.x - this.x, 2) + pow(attractor.y - this.y, 2));
    const angle = atan2(attractor.y - this.y, attractor.x - this.x);
    this.momentX += force * cos(angle);
    this.momentY += force * sin(angle);
  },

  tick() {
    this.momentX *= 0.8;
    this.momentY *= 0.8;
    this.velocityX += this.momentX / 100;
    this.velocityY += this.momentY / 100;
    this.x += this.velocityX / 100;
    this.y += this.velocityY / 100;
    this.trail.push({
      x: this.x,
      y: this.y });

    this.momentX = 0;
    this.momentY = 0;
  },

  draw(ctx) {
    this.tick();
    ctx.beginPath();
    ctx.arc(this.x, this.y, this.radius, 0, π * 2);
    ctx.fillStyle = this.style;
    ctx.fill();
    ctx.beginPath();
    for (let i = 0; i < this.trail.length; i++) {
      ctx.lineTo(this.trail[i].x, this.trail[i].y);
    }
    ctx.lineWidth = this.radius;
    ctx.strokeStyle = this.style;
    ctx.stroke();
  } };


const masses = [{
  x: width / 6,
  y: height / 6,
  radius: 10,
  mass: 1000,
  style: 'slateblue' },
{
  x: width / 2,
  y: height / 6,
  radius: 10,
  mass: 1000,
  style: 'slateblue' },
{
  x: width - width / 6,
  y: height / 6,
  radius: 10,
  mass: 1000,
  style: 'slateblue' },
{
  x: width / 6,
  y: height / 2,
  radius: 10,
  mass: 1000,
  style: 'slateblue' },
{
  x: width - width / 6,
  y: height / 2,
  radius: 10,
  mass: 1000,
  style: 'slateblue' },
{
  x: width / 6,
  y: height - height / 6,
  radius: 10,
  mass: 1000,
  style: 'slateblue' },
{
  x: width / 2,
  y: height - height / 6,
  radius: 10,
  mass: 1000,
  style: 'slateblue' },
{
  x: width - width / 6,
  y: height - height / 6,
  radius: 10,
  mass: 1000,
  style: 'slateblue' }];


const cursorMass = {
  x: width / 4,
  y: height / 4,
  radius: 20,
  mass: 0,
  style: 't.........完整代码请登录后点击上方下载按钮下载查看