def _transform(self, x):
        """
        Transform matrix/vector using axis conversion matrices.
        """
        if self._z_up:
            return x
        else:
            return (self._matrix.to_4x4() @ x @ self._matrix_inv.to_4x4())

        Transform matrix/vector using axis conversion matrices.
        
metadrive/third_party/kitsunetsuki/exporter/gltf/__init__.py