Neon map flyto

<!DOCTYPE html>
<html>
<head>
    <meta charset='utf-8' />
    <title></title>
    
    <meta name='viewport' content='initial-scale=1,maximum-scale=1,user-scalable=no' />
    <script src='https://api.tiles.mapbox.com/mapbox-gl-js/v0.11.1/mapbox-gl.js'></script>
    <link href='https://api.tiles.mapbox.com/mapbox-gl-js/v0.11.1/mapbox-gl.css' rel='stylesheet' />
    <style>
        body { margin:0; padding:0; }
        #map { position:absolute; top:0; bottom:0; width:100%; }
    </style>
</head>
<body>

var isAtStart = true;

function fly() {
    // depending on whether we're currently at point a or b, aim for
    // point a or b
    var target = isAtStart ? end : start;

// and now we're at the opposite point
    isAtStart = !isAtStart;

map.flyTo({
        // These options control the ending camera position: centered at
        // the target, at zoom level 9, and north up.
        center: target,
        zoom:  13,
        bearing: 0,

// These options control the flight curve, making it move
        // slowly and zoom out almost completely before starting
        // to pan.
        speed: 0.5, // make the flying slow
        curve: 1, // change the speed at which it zooms out

// This can be any easing function: it takes a number between
        // 0 and 1 and returns another number between 0 and 1.
        easing: function (t) {
            return t;
        }
    });
}
</script>

</body>
</html>

https://api.tiles.mapbox.com/mapbox-gl-js/v0.11.1/mapbox-gl.js