float yawDelta = yawSpeed * _yawRate * Time.deltaTime;
    float offCenterYaw = _CurrentYaw - yawCenter;

    // If we're moving away from the center, slow down as we approach the edge.
    if (yawDelta * offCenterYaw > 0)
    {
        float extremityYaw = offCenterYaw / yawRange;
        yawDelta *= 1.0f - extremityYaw * extremityYaw;
    }
    // Ensure we never overshoot the allowed range.
    _CurrentYaw = Mathf.Clamp(_CurrentYaw + yawDelta,
                              yawCenter - yawRange,
                              yawCenter + yawRange);