Draw SVG dashed line on scroll? : <p>I want to have a svg dashed line drawn on scroll and got stuck on this for 4hrs.</p>

<p>If it's just a straight line, I can easily animate it by setting stroke-dasharray on css animation, but it doesn't work on a dashed line.</p>

<p>Since there's a background image on body, I cannot use a mask trick either.</p>

<p>I just want to have a simple 45 degree diagonal dashed line (about 100px) drawn on scroll.</p>

<p>Any advice? </p>
