gistfile1.js

// not optimized for performance because the Fx.Tween object is continually recreated by calling $('big_picture').get('tween') with new options
$('left').addEvent('click', function(){  
    if(!$('left').hasClass('deactivated')) {  
        current_id = $('big_picture').get('class').replace('image_', '');  
        current_id--;
        $('big_picture').get('tween',{
            onComplete: function() {
                $('big_picture').set('src', 'pictures/' + current_id + '.jpg');  
                $('big_picture').fade(1);
                $('big_picture').set('class', 'image_' + current_id);
                if(current_id==1) { $('left').set('class', 'deactivated'); }  
                if(current_id==(number_of_pictures-1)) { $('right').erase('class');  }
            }
        });
        $('big_picture').fade('hide');
    }  
});  
// not optimized for performance because the Fx.Tween object is continually recreated by calling $('big_picture').get('tween') with new options
$('right').addEvent('click', function(){  
    if(!$('right').hasClass('deactivated')) {  
        current_id = $('big_picture').get('class').replace('image_', '');  
        current_id++;  
        $('big_picture').get('tween',{
            onComplete: function() {
                $('big_picture').set('src', 'pictures/' + current_id + '.jpg');  
                $('big_picture').fade(1);  
                $('big_picture').set('class', 'image_' + current_id);  
                if(current_id==2) { $('left').erase('class'); }  
                if(current_id==number_of_pictures) { $('right').set('class', 'deactivated'); }
            }
        });
        $('big_picture').fade('hide');  
    }  
});