js实现canvas银河系行星旋转轨迹动画效果代码-html代码-BFW代码库

js实现canvas银河系行星旋转轨迹动画效果代码

代码语言：html

所属分类：动画

代码描述：js实现canvas银河系行星旋转轨迹动画效果代码

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 >
<head>
<meta charset="UTF-8">
<title></title>
  
<style>
body {

  overflow: hidden;
}
canvas {
  
  position: absolute;
  top: 0;
  left: 0;
  background-color: black;
}

a {
  
  width: 200px;
  height: 200px;
  position: absolute;
  left: calc( 100% - 200px );
  top: calc( 100% - 130px );
}
img {
  width: 200px;
}
</style>

</head>
<body>

<canvas id="c"></canvas>
<script type="text/javascript" src="//repo.bfw.wiki/bfwrepo/js/dat.gui-min.js"></script>
<script>
    var w = c.width = window.innerWidth,
    h = c.height = window.innerHeight,
    ctx = c.getContext( '2d' ),
    
    opts = {
      
      lineCount: 100,
      starCount: 30,
      
      radVel: .01,
      lineBaseVel: .1,
      lineAddedVel: .1,
      lineBaseLife: .4,
      lineAddedLife: .01,
      
      starBaseLife: 10,
      starAddedLife: 10,
      
      ellipseTilt: -.3,
      ellipseBaseRadius: .15,
      ellipseAddedRadius: .02,
      ellipseAxisMultiplierX: 2,
      ellipseAxisMultiplierY: 1,
      ellipseCX: w / 2,
      ellipseCY: h / 2,
      
      repaintAlpha: .015
    },
    gui = new dat.GUI,
    
    lines = [],
    stars = [],
    tick = 0,
    first = true;

function init() {
  
  lines.length = stars.length = 0;
  
  ctx.globalCompositeOperation = 'source-over';
  ctx.fillStyle = '#333';
  ctx.fillRect( 0, 0, w, h );
  
  if( first ) {
    
    var f = gui.addFolder( 'logics' );
    f.add( opts, 'lineCount', 1, 300 );
    f.add( opts, 'starCount', 1, 300 );
    f.add( opts, 'radVel', 0, 1 );
    f.add( opts, 'lineBaseVel', .01, 1 );
    f.add( opts, 'lineAddedVel', 0, 1 );
    f.add( opts, 'lineBaseLife', 0, 1 );
    f.add( opts, 'lineAddedLife', 0, 1 );
    f.add( opts, 'starBaseLife', 0, 100 );
    f.add( opts, 'starAddedLife', 0, 100 );
       f = gui.addFolder( 'graphics' );
    f.add( opts, 'ellipseTilt', -Math.PI, Math.PI ).step( .1 );
    f.add( opts, 'ellipseBaseRadius', 0, .5 );
    f.add( opts, 'ellipseAddedRadius', 0, .5 );
    f.add( opts, 'ellipseAxisMultiplierX', 0, 3 );
    f.add( opts, 'ellipseAxisMultiplierY', 0, 3 );
    f.add( opts, 'ellipseCX', 0, w );
    f.add( opts, 'ellipseCY', 0, h );
    f.add( opts, 'repaintAlpha', 0, 1 );
    gui.add( window, 'init' ).name( 'reset animation' );
    gui.add( window, 'LuukLamers' );
    
    loop();
    first = false;
  }
}

function loop() {
  
  window.requestAnimationFrame( loop );
  step();
  draw();
}

function step() {
  
  tick += .5;
  
  if( lines.length < opts.lineCount && Math.random() < .5 )
    lines.push( new Line );
  
  if( stars.length < opts.starCount )
    stars.push( new Star );
  
  lines.map( function( line ) { line.step(); } );
  stars.map( function( star ) { star.step(); } );
}

function draw() {
  
  ctx.shadowBlur = 0;
  ctx.gl.........完整代码请登录后点击上方下载按钮下载查看