(function($){var selectors=[];var check_binded=false;var check_lock=false;var defaults={interval:250,force_process:false} var $window=$(window);var $prior_appeared;function process(){check_lock=false;for(var index=0;index=window_top&&top-($element.data('appear-top-offset')||0)<=window_top+ $window.height()&&left+ $element.width()>=window_left&&left-($element.data('appear-left-offset')||0)<=window_left+ $window.width()){return true;}else{return false;}} $.fn.extend({appear:function(options){var opts=$.extend({},defaults,options||{});var selector=this.selector||this;if(!check_binded){var on_check=function(){if(check_lock){return;} check_lock=true;setTimeout(process,opts.interval);};$(window).scroll(on_check).resize(on_check);check_binded=true;} if(opts.force_process){setTimeout(process,opts.interval);} selectors.push(selector);return $(selector);}});$.extend({force_appear:function(){if(check_binded){process();return true;};return false;}});})(jQuery);