Integrating isotope with custom post types - the functions.php code

functions.php

/** Set up custom taxonomy query */
function custom_taxonomies_terms_links() {
  global $post, $post_id;
	// get post by post id
	$post = &get_post($post->ID);
	// get post type by post
	$post_type = $post->post_type;
	// get post type taxonomies
	$taxonomies = get_object_taxonomies($post_type);
	foreach ($taxonomies as $taxonomy) {
		// get the terms related to post
		$terms = get_the_terms( $post->ID, $taxonomy );
		if ( !empty( $terms ) ) {
			$out = array();
			foreach ( $terms as $term )
				$out[] = $term->slug;
			$return = join( ' ', $out );
		}
	}
	return $return;
}