(function($){jQuery.extend({isOnScreen:function(box,container){for(var i in box){box[i]=parseFloat(box[i])};for(var i in container){container[i]=parseFloat(container[i])};if(!container){container={left:$(window).scrollLeft(),top:$(window).scrollTop(),width:$(window).width(),height:$(window).height()}}
if(box.left+box.width-container.left>0&&box.left<container.width+container.left&&box.top+box.height-container.top>0&&box.top<container.height+container.top)return true;return false;}})
jQuery.fn.isOnScreen=function(container){for(var i in container){container[i]=parseFloat(container[i])};if(!container){container={left:$(window).scrollLeft(),top:$(window).scrollTop(),width:$(window).width(),height:$(window).height()}}
if($(this).offset().left+$(this).width()-container.left>0&&$(this).offset().left<container.width+container.left&&$(this).offset().top+$(this).height()-container.top>0&&$(this).offset().top<container.height+container.top)return true;return false;}})(jQuery);