AngularJS Page Control Understanding

I had a co-worker do some AngularJS work for me. I'm just learning Angular and they are no longer working with me.

They used the following for "Page Control" --  Can you help me better understand all that this is doing? It seems quite complex. Is there an easier way to do this?

I believe the purpose of this was to do two things: 1) Smooth Scrolling and 2) A nav bar header that changes from clear when full page background to a white menu header on subsequent pages.

This is operational on this site: Making Your Life Count

     * Controller for the pages
     */

    app.controller('PageCtrl', pageCtrl);

    function pageCtrl($scope, $location,$window, $anchorScroll, $http, $sce) {

        $scope.scrollPos = 0;
        //scroll to section_id
        //$scope.scrollTo = function(id) {
        //    var old = $location.hash();
        //    $location.hash(id);
        //    $anchorScroll();
        //    //reset to old to keep any additional routing logic from kicking in
        //    $location.hash(old);
        //};

        $scope.scrollTo = function(eID) {
                // This scrolling function
                // is from http://www.itnewb.com/tutorial/Creating-the-Smooth-Scroll-Effect-with-JavaScript

                var startY = currentYPosition();
                var stopY = elmYPosition(eID);
                var distance = stopY > startY ? stopY - startY : startY - stopY;
                if (distance < 100) {
                    scrollTo(0, stopY); return;
                }
                var speed = Math.round(distance / 100);
                if (speed >= 20) speed = 20;
                var step = Math.round(distance / 25);
                var leapY = stopY > startY ? startY + step : startY - step;
                var timer = 0;
                if (stopY > startY) {
                    for ( var i=startY; i<stopY; i+=step ) {
                        setTimeout("window.scrollTo(0, "+leapY+")", timer * speed);
                        leapY += step; if (leapY > stopY) leapY = stopY; timer++;
                    } return;
                }
                for ( var i=startY; i>stopY; i-=step ) {
                    setTimeout("window.scrollTo(0, "+leapY+")", timer * speed);
                    leapY -= step; if (leapY < stopY) leapY = stopY; timer++;
                }

                function currentYPosition() {
                    // Firefox, Chrome, Opera, Safari
                    if (self.pageYOffset) return self.pageYOffset;
                    // Internet Explorer 6 - standards mode
                    if (document.documentElement && document.documentElement.scrollTop)
                        return document.documentElement.scrollTop;
                    // Internet Explorer 6, 7 and 8
                    if (document.body.scrollTop) return document.body.scrollTop;
                    return 0;
                }

                function elmYPosition(eID) {
                    var elm = document.getElementById(eID);
                    var y = elm.offsetTop;
                    var node = elm;
                    while (node.offsetParent && node.offsetParent != document.body) {
                        node = node.offsetParent;
                        y += node.offsetTop;
                    } return y;
                }

        };


        //render html code
        $scope.renderHtml = function (html_code) {
            return $sce.trustAsHtml(html_code);
        };

        //show or hide the jumbotron
        $scope.checkURl = function () {
            if ($location.url() == '/' || $location.url().indexOf('/#') > -1) return true;
            return false;
        };

        //footer class
        $scope.checkURlForFooter = function(){
            //console.log($window);
            if($location.url().indexOf('message') > -1 && $window.innerWidth > 450) return true;
            return false;
        }

        $scope.$on('$locationChangeStart', function(event) {
            $scope.checkbg = ! $scope.checkURl();
            //navigation highlight
            $scope.location = $location.url();
        });


        //accordion
        $scope.status = {
            isFirstOpen: true,
            isSecondOpen: false,
            isThirdOpen: false
        };

    }

Select allOpen in new window

Again, is this the best way to do this? Thanks.