developing facebook menu

gistfile1.js

var ondrag = false,
        pointStart = lastPoint = distance = currentTranslate = 0;
    $(window).on('mousedown mousemove mouseup touchmove touchstart touchend',function(event){
        console.log( event );
        switch(event.type) {
            case 'touchstart':
            case 'mousedown':
                ondrag = true;
                pointStart = lastPoint = event.pageX || event.originalEvent.touches[0].pageX;
                break;
            case 'mousemove':
            case 'touchmove':
                if( ondrag ) {
                    var mousepoint = event.pageX || event.originalEvent.touches[0].pageX;
                    var direction = mousepoint - lastPoint;
                    distance = mousepoint - pointStart;
                    currentTranslate += direction;
                    if( currentTranslate > navW ) {
                        currentTranslate = navW;
                    }
                    if( currentTranslate < 0 ) {
                        currentTranslate = 0;
                    }
                    translate( currentTranslate , $('#main, .handheld-header'), 'px' );
                    lastPoint = mousepoint;
                }
                break;
            case 'mouseup':
            case 'touchend':
                ondrag = false;
                if( currentTranslate > navW / 100 * 70 ) {
                    currentTranslate = navW;
                    translate( navW, $('#main, .handheld-header'), 'px' );
                } else {
                    currentTranslate = 0;
                    translate( 0, $('#main, .handheld-header'), 'px' );
                }
                distance = pointStart = lastPoint = 0;
                break;
        }
    });