text: /*
      Version 1.8.0
      The MIT License (MIT)
  
      Copyright (c) 2014 Dirk Groenen
  
      Permission is hereby granted, free of charge, to any person obtaining a copy of
      this software and associated documentation files (the "Software"), to deal in
      the Software without restriction, including without limitation the rights to
      use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
      the Software, and to permit persons to whom the Software is furnished to do so,
      subject to the following conditions:
  
      The above copyright notice and this permission notice shall be included in all
      copies or substantial portions of the Software.
  */
  
  (function($){
      $.fn.viewportChecker = function(useroptions){
          // Define options and extend with user
          var options = {
              classToAdd: 'visible',
              classToRemove : 'invisible',
              offset: 100,
              repeat: false,
              invertBottomOffset: true,
              callbackFunction: function(elem, action){},
              scrollHorizontal: false
          };
          $.extend(options, useroptions);
  
          // Cache the given element and height of the browser
          var $elem = this,
              windowSize = {height: $(window).height(), width: $(window).width()},
              scrollElem = ((navigator.userAgent.toLowerCase().indexOf('webkit') != -1) ? 'body' : 'html');
  
          /*
           * Main method that checks the elements and adds or removes the class(es)
           */
          this.checkElements = function(){
              var viewportStart, viewportEnd;
  
              // Set some vars to check with
              if(!options.scrollHorizontal){
                  viewportStart = $(scrollElem).scrollTop();
                  viewportEnd = (viewportStart + windowSize.height);
              }
              else{
                  viewportStart = $(scrollElem).scrollLeft();
                  viewportEnd = (viewportStart + windowSize.width);
              }
  
              // Loop through all given dom elements
              $elem.each(function(){
                  var $obj = $(this),
                      objOptions = {},
                      attrOptions = {};
  
                  //  Get any individual attribution data
                  if ($obj.data('vp-add-class'))
                      attrOptions.classToAdd = $obj.data('vp-add-class');
                  if ($obj.data('vp-remove-class'))
                      attrOptions.classToRemove = $obj.data('vp-remove-class');
                  if ($obj.data('vp-offset'))
                      attrOptions.offset = $obj.data('vp-offset');
                  if ($obj.data('vp-repeat'))
                      attrOptions.repeat = $obj.data('vp-repeat');
                  if ($obj.data('vp-scrollHorizontal'))
                      attrOptions.scrollHorizontal = $obj.data('vp-scrollHorizontal');
                  if ($obj.data('vp-invertBottomOffset'))
                      attrOptions.scrollHorizontal = $obj.data('vp-invertBottomOffset');
  
                  // Extend objOptions with data attributes and default options
                  $.extend(objOptions, options);
                  $.extend(objOptions, attrOptions);
  
                  // If class already exists; quit
                  if ($obj.hasClass(objOptions.classToAdd) && !objOptions.repeat){
                      return;
                  }
  
                  // Check if the offset is percentage based
                  if(String(objOptions.offset).indexOf("%") > 0)
                      objOptions.offset = (parseInt(objOptions.offset) / 100) * windowSize.height;
  
                  console.log(objOptions.offset);
  
                  // define the top position of the element and include the offset which makes is appear earlier or later
                  var elemStart = (!objOptions.scrollHorizontal) ? Math.round( $obj.offset().top ) + objOptions.offset : Math.round( $obj.offset().left ) + objOptions.offset,
                      elemEnd = (!objOptions.scrollHorizontal) ? elemStart + $obj.height() : elemStart + $obj.width();
  
                  if(objOptions.invertBottomOffset)
                  	elemEnd -= (objOptions.offset * 2);
  
                  // Add class if in viewport
                  if ((elemStart < viewportEnd) && (elemEnd > viewportStart)){
  
                      // remove class
                      $obj.removeClass(objOptions.classToRemove);
  
                      $obj.addClass(objOptions.classToAdd);
  
                      // Do the callback function. Callback wil send the jQuery object as parameter
                      objOptions.callbackFunction($obj, "add");
  
                  // Remove class if not in viewport and repeat is true
                  } else if ($obj.hasClass(objOptions.classToAdd) && (objOptions.repeat)){
                      $obj.removeClass(objOptions.classToAdd);
  
                      // Do the callback function.
                      objOptions.callbackFunction($obj, "remove");
                  }
              });
  
          };
  
          // Run checkelements on load and scroll
          $(window).bind("load scroll touchmove MSPointerMove", this.checkElements);
  
          // On resize change the height var
          $(window).resize(function(e){
              windowSize = {height: $(window).height(), width: $(window).width()},
              $elem.checkElements();
          });
  
          // trigger inital check if elements already visible
          this.checkElements();
  
          // Default jquery plugin behaviour
          return this;
      };
  })(jQuery);
  