Animate Scroll Path In Canvas

Animate Scroll Path In Canvas

Hi All,
first see this
http://joelb.me/scrollpath

now I made this canvas for my own
<canvas id="myCanvas" width="5000" height="5000"></canvas>
    <script>
        var canvas = document.getElementById('myCanvas');
        var context = canvas.getContext('2d');
       
        context.beginPath();
        context.moveTo(100, 100);

        // line 1
        context.lineTo(500, 100);

        // quadratic curve
        context.bezierCurveTo(1000, 100, 500, 800, 1000, 800);
       
        //Line 2
        context.bezierCurveTo(2000, 800, 1500, 800, 1300, 800);

        context.lineWidth = 40;
        context.strokeStyle = '#fff';
        context.stroke();

    </script>

Here my question is this How animate this line path as that website?