Get the direction of mouse movement

/*
 *  Get the direction of element movement 
 * @param  $element   Elemental jQuery object 
 * @param  event      Event object 
 * @return direction  Return a number ：0: On ,1: Right ,2: Next ,3: Left 
 **/
function getDirection($element, event) {
    var w = $element.width(),
        h = $element.height(),
        x =
            (event.pageX - $element.offset().left - w / 2) *
            (w > h ? h / w : 1),
        y = (event.pageY - $element.offset().top - h / 2) * (h > w ? w / h : 1),
        direction =
            Math.round((Math.atan2(y, x) * (180 / Math.PI) + 180) / 90 + 3) % 4;

    return direction;
}

$('#content')
    .on('mouseenter', function (event) {
        console.log('enter: ' + getDirection($(this), event));
    })
    .on('mouseleave', function (event) {
        console.log('leave: ' + getDirection($(this), event));
    });