Converts this quaternion to one with the same orientation but with a magnitude of 1.
正規化されると、クオータニオンはその向きを維持しますが、大きさは 1.0 です。
Note that this method will change the current quaternion. If you
want to keep the current quaternion unchanged, use the normalized property instead.
If this quaternion is too small to be normalized it will be set to Quaternion.identity.
関連項目: normalized 変数