public static AffineTransform3 FromRigidTransform(RigidTransform3 transform)
        {
            AffineTransform3 result;

            result.Translation = transform.position;
            result.Transform   = Mat3.FromQuaternion(transform.rotation);
            return(result);
        }
        public AffineTransform3 Multiply(RigidTransform3 transform)
        {
            AffineTransform3 result;

            result.Transform    = Mat3.FromQuaternion(transform.rotation);
            result.Transform    = result.Transform.Multiply(Transform);
            result.Translation  = transform.position.Transform(Transform);
            result.Translation += Translation;
            return(result);
        }