How to use laravel pagination outside laravel

Question

I'm currently working on a project that I need to paginate some SQL results. I'm using the Illuminate/Pagination package that comes with laravel. The package was loaded into my using composer (PHP dependency manager). But I'm having issue using the paginator class. Here is my code:

$perPage = 5;
$currentPage = isset($_GET['page']) ? $_GET['page'] : 1;
$offset = $perPage * ($currentPage - 1);

$sql = "SELECT * FROM post ORDER BY date DESC LIMIT $offset,$perPage;";
$query = $handler->query($sql);
$posts = $query->fetchAll(PDO::FETCH_OBJ);


$totalItem = count($posts);
$totalPage = ceil($totalItem / $perPage);

$currentItems = array_slice($posts, $offset, $perPage);

$paginator = new Illuminate\Pagination\Paginator($posts, $perPage, 
$currentPage); 
$paginator->render();