public function toArray() : array
    {
        $facets = array();
        $count = $this->getFacetNormalCount();

        for ($i = 0; $i < $count; $i++) {
            $facets[] = $this->getFacetNormal($i)->toArray();
        }

        return array(
            "name" => $this->getSolidName(),
            "facets" => $facets
        );
    }