private void UpdateHeadLookTarget()
    {
        if (this.IsApplyHeadLooking)
        {
            lock (locker)
            {
                if (this.isUpdatedFaceTracking)
                {
                    this.destinationFaceRotation             = FaceTrackingUtils.ExtractRotationFromMatrix(ref transformationM);
                    this.destinationFaceRotation.eulerAngles = new Vector3(-this.destinationFaceRotation.eulerAngles.x, -this.destinationFaceRotation.eulerAngles.y, this.destinationFaceRotation.eulerAngles.z);   // 鏡写しに回転するよう補正

                    this.isUpdatedFaceTracking = false;
                }
            }

            // ワールド座標中心に回す
            this.HeadLookTargetRotationCenter.rotation = this.destinationFaceRotation;
            // 回転対象のローカル座標に中心位置を戻す
            this.HeadLookTargetRotationCenter.position = this.HeadModel.position;
            // モデル全体(Root)の回転値を反映
            this.HeadLookTargetRotationCenter.rotation *= this.HeadModel.root.rotation;

            this.isInitialFiltering = false;
        }
        else
        {
            // Target に値を反映しない場合は、頭部モデルに追従
            this.HeadLookTargetRotationCenter.position = this.HeadModel.position;
            this.HeadLookTargetRotationCenter.rotation = this.HeadModel.rotation;
        }
    }
    private void UpdateTargetModel()
    {
        lock (locker)
        {
            if (this.isUpdatedFaceTracking)
            {
                this.destinationFaceRotation             = FaceTrackingUtils.ExtractRotationFromMatrix(ref transformationM);
                this.destinationFaceRotation.eulerAngles = new Vector3(-this.destinationFaceRotation.eulerAngles.x, -this.destinationFaceRotation.eulerAngles.y, this.destinationFaceRotation.eulerAngles.z);   // 鏡写しに回転するよう補正

                if (this.isLocal)
                {
                    this.destinationFaceRotation = Quaternion.Euler(this.targetFaceObject.transform.parent.TransformVector(this.destinationFaceRotation.eulerAngles));
                }

                this.isUpdatedFaceTracking = false;
            }
        }


        if (!this.isLocal)
        {
            this.destinationFaceRotation = this.destinationFaceRotation * this.initialModelHeadRotation;
        }
        else
        {
            this.destinationFaceRotation = this.initialModelHeadRotation * this.destinationFaceRotation;
        }

        // 毎フレーム頭部の回転値に対してLowPassFilteringして補間
        if (!isLocal)
        {
            this.targetFaceObject.transform.rotation = LowpassFilterQuaternion(this.targetFaceObject.transform.rotation, this.destinationFaceRotation, this.lowPassFactor, this.isInitialFiltering);
        }
        else
        {
            this.targetFaceObject.transform.localRotation = LowpassFilterQuaternion(this.targetFaceObject.transform.localRotation, this.destinationFaceRotation, this.lowPassFactor, this.isInitialFiltering);
        }

        this.isInitialFiltering = false;
    }