def create_normal_matrix(self, modelview):
normal_m = Matrix33.from_matrix44(modelview)<EOL>normal_m = normal_m.inverse<EOL>normal_m = normal_m.transpose()<EOL>return normal_m<EOL>
Creates a normal matrix from modelview matrix

Args:
    modelview: The modelview matrix

Returns:
    A 3x3 Normal matrix as a :py:class:`numpy.array`