IEnumerator rotate90(bool direction)
    {
        // direction == false -> rotate left
        // direction == true -> rotate right

        if (direction == true)
        {
            CurrentLookVector = (LookVector)(((int)CurrentLookVector + 1) % 4);
        }

        else
        {
            CurrentLookVector = (LookVector)(((int)CurrentLookVector - 1));

            if ((int)(CurrentLookVector) == -1)
            {
                CurrentLookVector = (LookVector)(3);
            }
        }


        Quaternion startRotation = transform.rotation;

        Quaternion endRotation;

        if (direction == false)
        {
            endRotation = startRotation * Quaternion.Euler(0, -90, 0);
        }

        else
        {
            endRotation = startRotation * Quaternion.Euler(0, 90, 0);
        }

        float t = 0.0f;

        float seconds = CameraRotateTime;

        while (t <= 1.0f)
        {
            t += Time.deltaTime / seconds;

            transform.rotation = Quaternion.Lerp(startRotation, endRotation, Mathf.SmoothStep(0.0f, 1.0f, t));

            yield return new WaitForFixedUpdate();
        }

        rotating = false;
        yield return null;
    }