private SteeringOut ObstacleAvoidance(LayerMask obstDef)
        {
            SteeringOut steeringOut = new SteeringOut();

            RaycastHit2D rcHit = Physics2D.Raycast(_owner.Position, _owner.VectorHeading(),
                                                   _owner.obsFeelerLen, obstDef);

            /* Draw feeler
             * Debug.DrawRay (_owner.Position, new Vector3 (_owner.VectorHeading().x,
             *  _owner.VectorHeading ().y, 0) * _owner.obsFeelerLen, Color.green);
             */

            if (rcHit.collider == null)
            {
                return(steeringOut);
            }

            Vector2 toObst           = (Vector2)rcHit.transform.position - _owner.Position;
            float   toObstDeltaAngle = Utils.DeltaAngle(_owner.DegreeHeading(), Utils.Vector2Angle(toObst));

            float newTargetAngle = _owner.DegreeHeading();

            if (toObstDeltaAngle < 0)
            {
                newTargetAngle = newTargetAngle + 90 + toObstDeltaAngle;
            }
            else
            {
                newTargetAngle = newTargetAngle - 90 + toObstDeltaAngle;
            }

            float deltaAngle = Utils.AbsDeltaAngle(newTargetAngle, _owner.DegreeHeading());

            steeringOut.LimitSpeed  = DeltaAngle2LimitSpeed(deltaAngle);
            steeringOut.TargetAngle = newTargetAngle;

            return(steeringOut);
        }