fromPath method
filePath - path of the file to be loaded
Implementation
@override
Future<CubeTexture?> fromPath(String filePath) async{
  final image = await _loader.fromPath(filePath);
  texture.images.add(image);
  loaded ++;
  if ( loaded == 6 ) {
    texture.needsUpdate = true;
    return texture;
  }
  return null;
}