canvas Drawing Kaleidoscope Effect (Code Sharing)

2021-07-13 03:46:47
OfStack
Without saying much, please look at the code:

<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title> Kaleidoscope </title>
<style>
canvas{
 background:#eee;
 }
</style>
<script>
window.onload = function(){
 var canvas = document.getElementById("canvas");
 var cobj = canvas.getContext("2d");
 var arr = [];
 var t=setInterval(function(){
  cobj.clearRect(0,0,600,600);
   for(var i=0;i<arr.length;i++){
  cobj.save();
  cobj.translate(300,300);
  cobj.scale(arr[i].scales,arr[i].scales);
  cobj.rotate(arr[i].angle*Math.PI/180);
  cobj.fillStyle = arr[i].color;
  cobj.fillRect(arr[i].num,arr[i].num,30,30);
  cobj.restore();
 }
 },50);
 setInterval(function(){
  for(var i=0;i<arr.length;i++){
    if(arr[i].num<=0){
   arr.splice(i,1);
   continue;
  }
  arr[i].angle+=2;
  arr[i].num-=0.2;
  arr[i].scales-=0.002;
  if(arr[i].scales<=0.2){
   arr[i].scales=0.2;
   }
  }
  },50);
 setInterval(function(){
  var rect = {angle:0,num:150,scales:1,color:"rgb("+parseInt(Math.random()*255)+","+parseInt(Math.random()*255)+","+parseInt(Math.random()*255)+")"};
  arr.push(rect);
  },600);
 }
</script>
</head>
<body>
<canvas width="600" height="600" id="canvas"></canvas>
</body>
</html>