public void SetExpression(string emotion, float amount)
    {
        var exp = _faceController.GetExpressionController(emotion);

        if (_currentEmotion != null && _currentEmotion != exp)
        {
            _currentEmotion.TargetAmount = 0;
        }

        _currentEmotion = exp;
        _currentEmotion.TargetAmount = amount;
    }