https://homegrowngardencentre.com/wp-content/themes/homegrown/assets/js/inViewport.js?ver=7.1.2

1/*! inViewport 0.0.1 
2 *  jQuery plugin by Moob
3 * ======================== 
4 *  (requires jQuery) 
5 */  
6(function ($) {
7
8    var vph=0;
9    function getViewportDimensions(){
10        vph = Math.max(document.documentElement.clientHeight, window.innerHeight || 0);
11    }
12    getViewportDimensions();    
13    //on resize/scroll
14    $(window).on('resize orientationChanged', function(){
15        getViewportDimensions();
16    });            
17    
18    $.fn.inViewport = function (whenInView, whenNotInView) {                  
19        return this.each(function () {
20            var el = $(this),
21                inviewalreadycalled = false,
22                notinviewalreadycalled = false;                            
23            //on resize/scroll
24            $(window).on('resize orientationChanged scroll', function(){
25                checkInView();
26            });               
27            function checkInView(){
28                var rect = el[0].getBoundingClientRect(),
29                    t = rect.top,
30                    b = rect.bottom;
31                if(t<vph && b>0){
32                    if(!inviewalreadycalled){
33                        whenInView.call(el);
34                        inviewalreadycalled = true;
35                        notinviewalreadycalled = false;
36                    }
37                } else {
38                    if(!notinviewalreadycalled){
39                        whenNotInView.call(el);
40                        notinviewalreadycalled = true;
41                        inviewalreadycalled = false;
42                    }
43                }
44            }
45            //initial check
46            checkInView();                
47        });
48    }             
49}(jQuery));