I have drawn a polygon with the following code. Now I want to resize that polygon animatedly. In detail, I want to set an angular movement to one side of the polygon, such that it makes an arc, and so changes the size of polygon. I googled for everything regarding the polygon animation, but didn't get anything, though there is plenty of material for line animation.

```
<script>
    $(function(){
    var c=$('#myCanvas');
    var ctx=c.getContext("2d");
    ctx.fillStyle='#f00';
    ctx.beginPath();
    ctx.moveTo(0,40);
    ctx.lineTo(80,200);
    ctx.lineTo(100,200);
    ctx.lineTo(40,0);
    ctx.closePath();
    ctx.fill();
</script>
</div>

```

Is it possible to pick a line of a polygon and animate it, to change the shape of the polygon?