normalizeNormals() {

		const normals = this.attributes.normal;

		for ( let i = 0, il = normals.count; i < il; i ++ ) {

			_vector$8.fromBufferAttribute( normals, i );

			_vector$8.normalize();

			normals.setXYZ( i, _vector$8.x, _vector$8.y, _vector$8.z );

		}

	}
Ensures every normal vector in a geometry will have a magnitude of `1`. This will
correct lighting on the geometry surfaces.