/// <summary>
        /// Stores that the given vehicle's path has been dynamically recalculated at the current frame.
        /// </summary>
        /// <param name="vehicleId"></param>
#if PATHRECALC
        internal static void MarkPathRecalculation(ushort vehicleId, ushort segmentId)
        {
            VehicleState state = VehicleStateManager.GetVehicleState(vehicleId);

            if (state == null)
            {
                return;
            }
            state.LastPathRecalculation          = GetVehiclePathRecalculationFrame();
            state.LastPathRecalculationSegmentId = segmentId;
            state.PathRecalculationRequested     = true;
        }
        /// <summary>
        /// Displays vehicle ids over vehicles
        /// </summary>
        private void _guiVehicles()
        {
            GUIStyle              _counterStyle = new GUIStyle();
            Array16 <Vehicle>     vehicles      = Singleton <VehicleManager> .instance.m_vehicles;
            LaneConnectionManager connManager   = Singleton <LaneConnectionManager> .instance;
            SimulationManager     simManager    = Singleton <SimulationManager> .instance;
            NetManager            netManager    = Singleton <NetManager> .instance;

            for (int i = 1; i < vehicles.m_size; ++i)
            {
                Vehicle vehicle = vehicles.m_buffer[i];
                if (vehicle.m_flags == 0)                 // node is unused
                {
                    continue;
                }

                Vector3 vehPos    = vehicle.GetLastFramePosition();
                var     screenPos = Camera.main.WorldToScreenPoint(vehPos);
                screenPos.y = Screen.height - screenPos.y;

                if (screenPos.z < 0)
                {
                    continue;
                }

                var camPos = simManager.m_simulationView.m_position;
                var diff   = vehPos - camPos;
                if (diff.magnitude > DebugCloseLod)
                {
                    continue;                     // do not draw if too distant
                }
                var zoom = 1.0f / diff.magnitude * 150f;

                _counterStyle.fontSize         = (int)(10f * zoom);
                _counterStyle.normal.textColor = new Color(1f, 1f, 1f);
                //_counterStyle.normal.background = MakeTex(1, 1, new Color(0f, 0f, 0f, 0.4f));

                VehicleState      vState  = VehicleStateManager.GetVehicleState((ushort)i);
                PathUnit.Position?curPos  = vState?.GetCurrentPathPosition(ref vehicle);
                PathUnit.Position?nextPos = vState?.GetNextPathPosition(ref vehicle);
                bool?  startNode          = vState?.CurrentSegmentEnd?.StartNode;
                ushort?segmentId          = vState?.CurrentSegmentEnd?.SegmentId;
                ushort?transitNodeId      = vState?.CurrentSegmentEnd?.NodeId;

                /*float distanceToTransitNode = Single.NaN;
                 * float timeToTransitNode = Single.NaN;*/
                float vehSpeed = vehicle.GetLastFrameVelocity().magnitude;

                Vector3?targetPos = null;
                if (transitNodeId != null)
                {
                    targetPos = netManager.m_nodes.m_buffer[(ushort)transitNodeId].m_position;
                }

                /*if (transitNodeId != null && segmentId != null && startNode != null && curPos != null) {
                 *      bool outgoing = false;
                 *      connManager.GetLaneEndPoint((ushort)segmentId, (bool)startNode, ((PathUnit.Position)curPos).m_lane, null, null, out outgoing, out targetPos);
                 * }*/

                /*if (targetPos != null) {
                 *      distanceToTransitNode = ((Vector3)targetPos - vehPos).magnitude;
                 *      if (vehSpeed > 0)
                 *              timeToTransitNode = distanceToTransitNode / vehSpeed;
                 *      else
                 *              timeToTransitNode = Single.PositiveInfinity;
                 * }*/
                String labelStr = "V #" + i + " @ " + vState?.CurrentSegmentEnd?.SegmentId;
                //String labelStr = "Veh. " + i + " @ " + String.Format("{0:0.##}", vehSpeed) + "/" + (vState != null ? vState.CurrentMaxSpeed.ToString() : "-") + " (" + (vState != null ? vState.VehicleType.ToString() : "-") + ", valid? " + (vState != null ? vState.Valid.ToString() : "-") + ")" + ", len: " + (vState != null ? vState.TotalLength.ToString() : "-") + ", state: " + (vState != null ? vState.JunctionTransitState.ToString() : "-");
#if PATHRECALC
                labelStr += ", recalc: " + (vState != null ? vState.LastPathRecalculation.ToString() : "-");
#endif
                //labelStr += "\npos: " + curPos?.m_segment + "(" + curPos?.m_lane + ")->" + nextPos?.m_segment + "(" + nextPos?.m_lane + ")" /* + ", dist: " + distanceToTransitNode + ", time: " + timeToTransitNode*/ + ", last update: " + vState?.LastPositionUpdate;
#if USEPATHWAITCOUNTER
                labelStr += ", wait: " + vState?.PathWaitCounter;
#endif

                Vector2 dim       = _counterStyle.CalcSize(new GUIContent(labelStr));
                Rect    labelRect = new Rect(screenPos.x - dim.x / 2f, screenPos.y - dim.y - 50f, dim.x, dim.y);

                GUI.Box(labelRect, labelStr, _counterStyle);

                //_counterStyle.normal.background = null;
            }
        }
        public static bool ShouldRecalculatePath(ushort vehicleId, ref Vehicle vehicleData, int maxBlockCounter, out ushort segmentId)
        {
            segmentId = 0;
            if (!Options.IsDynamicPathRecalculationActive())
            {
                return(false);
            }
            if (Options.simAccuracy > 1)
            {
                return(false);
            }
            if (!CustomPathManager.InitDone
#if EXTRAPF
                || CustomPathManager.ExtraQueuedPathFinds > Options.someValue8
#elif QUEUEDSTATS
                || CustomPathManager.TotalQueuedPathFinds > Options.someValue8
#endif
                )
            {
                return(false);
            }
            if (vehicleData.m_leadingVehicle != 0)
            {
                return(false);
            }
            if (vehicleData.m_path == 0)
            {
                return(false);
            }

            /*if (vehicleData.GetLastFrameVelocity().magnitude > Options.someValue9)
             *      return false;*/
            /*if ((vehicleData.m_flags & Vehicle.Flags.Emergency2) == 0)
             *      return false;*/
            VehicleState state = VehicleStateManager.GetVehicleState(vehicleId);
            if (state == null || state.LastPathRecalculation >= GetVehiclePathRecalculationFrame())
            {
                return(false);
            }
            if (vehicleData.GetLastFrameVelocity().magnitude > Options.someValue9 * state.CurrentMaxSpeed)
            {
                return(false);
            }
            NetManager netManager   = Singleton <NetManager> .instance;
            bool       recalc       = false;
            ushort     outSegmentId = 0;
            state.ProcessCurrentAndNextPathPosition(ref vehicleData, delegate(ref PathUnit.Position curPos, ref PathUnit.Position nextPos) {
                if (curPos.m_segment == 0 || nextPos.m_segment == 0)
                {
                    return;
                }
                if (state.LastPathRecalculationSegmentId == curPos.m_segment)
                {
                    return;
                }
                if (curPos.m_lane >= netManager.m_segments.m_buffer[curPos.m_segment].Info.m_lanes.Length)
                {
                    return;
                }
                if (nextPos.m_lane >= netManager.m_segments.m_buffer[nextPos.m_segment].Info.m_lanes.Length)
                {
                    return;
                }

                if (CustomRoadAI.laneMeanSpeeds[nextPos.m_segment] == null || nextPos.m_lane >= CustomRoadAI.laneMeanSpeeds[nextPos.m_segment].Length)
                {
                    return;
                }

                if (CustomRoadAI.laneMeanSpeeds[nextPos.m_segment][nextPos.m_lane] >= 60)
                {
                    return;
                }

                /*if (CustomRoadAI.laneMeanDensities[nextPos.m_segment] == null || nextPos.m_lane >= CustomRoadAI.laneMeanDensities[nextPos.m_segment].Length)
                 *      return;
                 * byte nextDensity = CustomRoadAI.laneMeanDensities[nextPos.m_segment][nextPos.m_lane];
                 *
                 * if (nextDensity < 0.5) // TODO incorporate number of lanes (density is measured relatively)
                 *      return;*/

                recalc       = true;
                outSegmentId = curPos.m_segment;
            });

            segmentId = outSegmentId;
            return(recalc);
        }
        /// <summary>
        /// Checks for traffic lights and priority signs when changing segments (for road & rail vehicles).
        /// Sets the maximum allowed speed <paramref name="maxSpeed"/> if segment change is not allowed (otherwise <paramref name="maxSpeed"/> has to be set by the calling method).
        /// </summary>
        /// <param name="vehicleId">vehicle id</param>
        /// <param name="vehicleData">vehicle data</param>
        /// <param name="lastFrameData">last frame data of vehicle</param>
        /// <param name="isRecklessDriver">if true, this vehicle ignores red traffic lights and priority signs</param>
        /// <param name="prevPos">previous path position</param>
        /// <param name="prevTargetNodeId">previous target node</param>
        /// <param name="prevLaneID">previous lane</param>
        /// <param name="position">current path position</param>
        /// <param name="targetNodeId">transit node</param>
        /// <param name="laneID">current lane</param>
        /// <param name="nextPosition">next path position</param>
        /// <param name="nextTargetNodeId">next target node</param>
        /// <param name="maxSpeed">maximum allowed speed (only valid if method returns false)</param>
        /// <returns>true, if the vehicle may change segments, false otherwise.</returns>
        internal static bool MayChangeSegment(ushort vehicleId, ref Vehicle vehicleData, ref Vehicle.Frame lastFrameData, bool isRecklessDriver, ref PathUnit.Position prevPos, ushort prevTargetNodeId, uint prevLaneID, ref PathUnit.Position position, ushort targetNodeId, uint laneID, ref PathUnit.Position nextPosition, ushort nextTargetNodeId, out float maxSpeed, bool debug = false)
        {
            debug = false;
            if (prevTargetNodeId != targetNodeId)
            {
                // method should only be called if targetNodeId == prevTargetNode
                maxSpeed = 0f;
                return(true);
            }

            bool         forceUpdatePos = false;
            VehicleState vehicleState   = null;

            try {
                vehicleState = VehicleStateManager.GetVehicleState(vehicleId);

                if (vehicleState == null)
                {
                    VehicleStateManager.OnPathFindReady(vehicleId, ref vehicleData);
                    vehicleState = VehicleStateManager.GetVehicleState(vehicleId);

                    if (vehicleState == null)
                    {
#if DEBUG
                        Log._Debug($"Could not get vehicle state of {vehicleId}!");
#endif
                    }
                    else
                    {
                        forceUpdatePos = true;
                    }
                }
            } catch (Exception e) {
                Log.Error("VehicleAI MayChangeSegment vehicle state error: " + e.ToString());
            }

            if (forceUpdatePos || Options.simAccuracy >= 2)
            {
                try {
                    VehicleStateManager.UpdateVehiclePos(vehicleId, ref vehicleData, ref prevPos, ref position);
                } catch (Exception e) {
                    Log.Error("VehicleAI MayChangeSegment Error: " + e.ToString());
                }
            }

            var netManager = Singleton <NetManager> .instance;

            uint currentFrameIndex        = Singleton <SimulationManager> .instance.m_currentFrameIndex;
            uint prevTargetNodeLower8Bits = (uint)((prevTargetNodeId << 8) / 32768);
            uint random = currentFrameIndex - prevTargetNodeLower8Bits & 255u;

            bool isRailVehicle = (vehicleData.Info.m_vehicleType & (VehicleInfo.VehicleType.Train | VehicleInfo.VehicleType.Metro)) != VehicleInfo.VehicleType.None;

            NetNode.Flags targetNodeFlags    = netManager.m_nodes.m_buffer[targetNodeId].m_flags;
            bool          hasTrafficLight    = (targetNodeFlags & NetNode.Flags.TrafficLights) != NetNode.Flags.None;
            bool          checkTrafficLights = false;
            if (!isRailVehicle)
            {
                // check if to check space

#if DEBUG
                if (debug)
                {
                    Log._Debug($"CustomVehicleAI.MayChangeSegment: Vehicle {vehicleId} is not a train.");
                }
#endif

                var  prevLaneFlags    = (NetLane.Flags)netManager.m_lanes.m_buffer[(int)((UIntPtr)prevLaneID)].m_flags;
                var  hasCrossing      = (targetNodeFlags & NetNode.Flags.LevelCrossing) != NetNode.Flags.None;
                var  isJoinedJunction = (prevLaneFlags & NetLane.Flags.JoinedJunction) != NetLane.Flags.None;
                bool checkSpace       = !Flags.getEnterWhenBlockedAllowed(prevPos.m_segment, netManager.m_segments.m_buffer[prevPos.m_segment].m_startNode == targetNodeId) && !isRecklessDriver;
                //TrafficLightSimulation nodeSim = TrafficLightSimulation.GetNodeSimulation(destinationNodeId);
                //if (timedNode != null && timedNode.vehiclesMayEnterBlockedJunctions) {
                //	checkSpace = false;
                //}

                if (checkSpace)
                {
                    // check if there is enough space
                    if ((targetNodeFlags & (NetNode.Flags.Junction | NetNode.Flags.OneWayOut | NetNode.Flags.OneWayIn)) == NetNode.Flags.Junction &&
                        netManager.m_nodes.m_buffer[targetNodeId].CountSegments() != 2)
                    {
                        var len = vehicleData.CalculateTotalLength(vehicleId) + 2f;
                        if (!netManager.m_lanes.m_buffer[(int)((UIntPtr)laneID)].CheckSpace(len))
                        {
                            var sufficientSpace = false;
                            if (nextPosition.m_segment != 0 && netManager.m_lanes.m_buffer[(int)((UIntPtr)laneID)].m_length < 30f)
                            {
                                NetNode.Flags nextTargetNodeFlags = netManager.m_nodes.m_buffer[nextTargetNodeId].m_flags;
                                if ((nextTargetNodeFlags & (NetNode.Flags.Junction | NetNode.Flags.OneWayOut | NetNode.Flags.OneWayIn)) != NetNode.Flags.Junction ||
                                    netManager.m_nodes.m_buffer[nextTargetNodeId].CountSegments() == 2)
                                {
                                    uint nextLaneId = PathManager.GetLaneID(nextPosition);
                                    if (nextLaneId != 0u)
                                    {
                                        sufficientSpace = netManager.m_lanes.m_buffer[(int)((UIntPtr)nextLaneId)].CheckSpace(len);
                                    }
                                }
                            }
                            if (!sufficientSpace)
                            {
                                maxSpeed = 0f;
                                try {
                                    if (vehicleState != null)
                                    {
#if DEBUG
                                        if (debug)
                                        {
                                            Log._Debug($"Vehicle {vehicleId}: Setting JunctionTransitState to BLOCKED");
                                        }
#endif

                                        vehicleState.JunctionTransitState = VehicleJunctionTransitState.Blocked;
                                    }
                                } catch (Exception e) {
                                    Log.Error("VehicleAI MayChangeSegment error while setting junction state to BLOCKED: " + e.ToString());
                                }
                                return(false);
                            }
                        }
                    }
                }

                checkTrafficLights = (!isJoinedJunction || hasCrossing);
            }
            else
            {
#if DEBUG
                if (debug)
                {
                    Log._Debug($"CustomVehicleAI.MayChangeSegment: Vehicle {vehicleId} is a train.");
                }
#endif

                checkTrafficLights = true;
            }

            try {
                if (vehicleState != null && vehicleState.JunctionTransitState == VehicleJunctionTransitState.Blocked)
                {
#if DEBUG
                    if (debug)
                    {
                        Log._Debug($"Vehicle {vehicleId}: Setting JunctionTransitState from BLOCKED to ENTER");
                    }
#endif
                    vehicleState.JunctionTransitState = VehicleJunctionTransitState.Enter;
                }

                if ((vehicleData.m_flags & Vehicle.Flags.Emergency2) == 0)
                {
                    if (hasTrafficLight && checkTrafficLights)
                    {
#if DEBUG
                        if (debug)
                        {
                            Log._Debug($"CustomVehicleAI.MayChangeSegment: Node {targetNodeId} has a traffic light.");
                        }
#endif

                        var destinationInfo = netManager.m_nodes.m_buffer[targetNodeId].Info;

                        if (vehicleState != null && vehicleState.JunctionTransitState == VehicleJunctionTransitState.None)
                        {
#if DEBUG
                            if (debug)
                            {
                                Log._Debug($"Vehicle {vehicleId}: Setting JunctionTransitState to ENTER (1)");
                            }
#endif
                            vehicleState.JunctionTransitState = VehicleJunctionTransitState.Enter;
                        }

                        RoadBaseAI.TrafficLightState vehicleLightState;
                        RoadBaseAI.TrafficLightState pedestrianLightState;
                        bool vehicles;
                        bool pedestrians;
                        CustomRoadAI.GetTrafficLightState(vehicleId, ref vehicleData, targetNodeId, prevPos.m_segment, prevPos.m_lane, position.m_segment, ref netManager.m_segments.m_buffer[prevPos.m_segment], currentFrameIndex - prevTargetNodeLower8Bits, out vehicleLightState, out pedestrianLightState, out vehicles, out pedestrians);

                        if (vehicleData.Info.m_vehicleType == VehicleInfo.VehicleType.Car && isRecklessDriver)                           // no reckless driving at railroad crossings
                        {
                            vehicleLightState = RoadBaseAI.TrafficLightState.Green;
                        }

#if DEBUG
                        if (debug)
                        {
                            Log._Debug($"CustomVehicleAI.MayChangeSegment: Vehicle {vehicleId} has {vehicleLightState} at node {targetNodeId}");
                        }
#endif

                        if (!vehicles && random >= 196u)
                        {
                            vehicles = true;
                            RoadBaseAI.SetTrafficLightState(targetNodeId, ref netManager.m_segments.m_buffer[prevPos.m_segment], currentFrameIndex - prevTargetNodeLower8Bits, vehicleLightState, pedestrianLightState, vehicles, pedestrians);
                        }

                        var stopCar = false;
                        switch (vehicleLightState)
                        {
                        case RoadBaseAI.TrafficLightState.RedToGreen:
                            if (random < 60u)
                            {
                                stopCar = true;
                            }
                            else
                            {
#if DEBUG
                                if (debug)
                                {
                                    Log._Debug($"Vehicle {vehicleId}: Setting JunctionTransitState to LEAVE (RedToGreen)");
                                }
#endif
                                if (vehicleState != null)
                                {
                                    vehicleState.JunctionTransitState = VehicleJunctionTransitState.Leave;
                                }
                            }
                            break;

                        case RoadBaseAI.TrafficLightState.Red:
                            stopCar = true;
                            break;

                        case RoadBaseAI.TrafficLightState.GreenToRed:
                            if (random >= 30u)
                            {
                                stopCar = true;
                            }
                            else if (vehicleState != null)
                            {
#if DEBUG
                                if (debug)
                                {
                                    Log._Debug($"Vehicle {vehicleId}: Setting JunctionTransitState to LEAVE (GreenToRed)");
                                }
#endif
                                vehicleState.JunctionTransitState = VehicleJunctionTransitState.Leave;
                            }
                            break;
                        }

                        /*if ((vehicleLightState == RoadBaseAI.TrafficLightState.Green || vehicleLightState == RoadBaseAI.TrafficLightState.RedToGreen) && !Flags.getEnterWhenBlockedAllowed(prevPos.m_segment, netManager.m_segments.m_buffer[prevPos.m_segment].m_startNode == targetNodeId)) {
                         *      var hasIncomingCars = TrafficPriority.HasIncomingVehiclesWithHigherPriority(vehicleId, targetNodeId);
                         *
                         *      if (hasIncomingCars) {
                         *              // green light but other cars are incoming and they have priority: stop
                         *              stopCar = true;
                         *      }
                         * }*/

                        if (stopCar)
                        {
                            if (vehicleState != null)
                            {
#if DEBUG
                                if (debug)
                                {
                                    Log._Debug($"Vehicle {vehicleId}: Setting JunctionTransitState to STOP");
                                }
#endif
                                vehicleState.JunctionTransitState = VehicleJunctionTransitState.Stop;
                            }
                            maxSpeed = 0f;
                            return(false);
                        }
                    }
                    else if (vehicleState != null)
                    {
#if DEBUG
                        //bool debug = destinationNodeId == 10864;
                        //bool debug = destinationNodeId == 13531;
                        //bool debug = false;// targetNodeId == 5027;
#endif
                        //bool debug = false;
#if DEBUG
                        if (debug)
                        {
                            Log._Debug($"Vehicle {vehicleId} is arriving @ seg. {prevPos.m_segment} ({position.m_segment}, {nextPosition.m_segment}), node {targetNodeId} which is not a traffic light.");
                        }
#endif

                        var prioritySegment = TrafficPriority.GetPrioritySegment(targetNodeId, prevPos.m_segment);
                        if (prioritySegment != null)
                        {
#if DEBUG
                            if (debug)
                            {
                                Log._Debug($"Vehicle {vehicleId} is arriving @ seg. {prevPos.m_segment} ({position.m_segment}, {nextPosition.m_segment}), node {targetNodeId} which is not a traffic light and is a priority segment.");
                            }
#endif
                            //if (prioritySegment.HasVehicle(vehicleId)) {
#if DEBUG
                            if (debug)
                            {
                                Log._Debug($"Vehicle {vehicleId}: segment target position found");
                            }
#endif
#if DEBUG
                            if (debug)
                            {
                                Log._Debug($"Vehicle {vehicleId}: global target position found. carState = {vehicleState.JunctionTransitState.ToString()}");
                            }
#endif
                            var   currentFrameIndex2 = Singleton <SimulationManager> .instance.m_currentFrameIndex;
                            var   frame = currentFrameIndex2 >> 4;
                            float speed = lastFrameData.m_velocity.magnitude;

                            if (vehicleState.JunctionTransitState == VehicleJunctionTransitState.None)
                            {
#if DEBUG
                                if (debug)
                                {
                                    Log._Debug($"Vehicle {vehicleId}: Setting JunctionTransitState to ENTER (prio)");
                                }
#endif
                                vehicleState.JunctionTransitState = VehicleJunctionTransitState.Enter;
                            }

                            if (vehicleState.JunctionTransitState != VehicleJunctionTransitState.Leave)
                            {
                                bool hasIncomingCars;
                                switch (prioritySegment.Type)
                                {
                                case SegmentEnd.PriorityType.Stop:
#if DEBUG
                                    if (debug)
                                    {
                                        Log._Debug($"Vehicle {vehicleId}: STOP sign. waittime={vehicleState.WaitTime}, vel={speed}");
                                    }
#endif

                                    if (Options.simAccuracy <= 2 || (Options.simAccuracy >= 3 && vehicleState.WaitTime < MaxPriorityWaitTime))
                                    {
#if DEBUG
                                        if (debug)
                                        {
                                            Log._Debug($"Vehicle {vehicleId}: Setting JunctionTransitState to STOP (wait)");
                                        }
#endif
                                        vehicleState.JunctionTransitState = VehicleJunctionTransitState.Stop;

                                        if (speed <= TrafficPriority.maxStopVelocity)
                                        {
                                            vehicleState.WaitTime++;

                                            float minStopWaitTime = UnityEngine.Random.Range(0f, 3f);
                                            if (vehicleState.WaitTime >= minStopWaitTime)
                                            {
                                                if (Options.simAccuracy >= 4)
                                                {
                                                    vehicleState.JunctionTransitState = VehicleJunctionTransitState.Leave;
                                                }
                                                else
                                                {
                                                    hasIncomingCars = TrafficPriority.HasIncomingVehiclesWithHigherPriority(vehicleId, ref vehicleData, ref prevPos, ref position);
#if DEBUG
                                                    if (debug)
                                                    {
                                                        Log._Debug($"hasIncomingCars: {hasIncomingCars}");
                                                    }
#endif

                                                    if (hasIncomingCars)
                                                    {
                                                        maxSpeed = 0f;
                                                        return(false);
                                                    }
#if DEBUG
                                                    if (debug)
                                                    {
                                                        Log._Debug($"Vehicle {vehicleId}: Setting JunctionTransitState to LEAVE (min wait timeout)");
                                                    }
#endif
                                                    vehicleState.JunctionTransitState = VehicleJunctionTransitState.Leave;
                                                }
                                            }
                                            else
                                            {
                                                maxSpeed = 0;
                                                return(false);
                                            }
                                        }
                                        else
                                        {
                                            vehicleState.WaitTime = 0;
                                            maxSpeed = 0f;
                                            return(false);
                                        }
                                    }
                                    else
                                    {
#if DEBUG
                                        if (debug)
                                        {
                                            Log._Debug($"Vehicle {vehicleId}: Setting JunctionTransitState to LEAVE (max wait timeout)");
                                        }
#endif
                                        vehicleState.JunctionTransitState = VehicleJunctionTransitState.Leave;
                                    }
                                    break;

                                case SegmentEnd.PriorityType.Yield:
#if DEBUG
                                    if (debug)
                                    {
                                        Log._Debug($"Vehicle {vehicleId}: YIELD sign. waittime={vehicleState.WaitTime}");
                                    }
#endif

                                    if (Options.simAccuracy <= 2 || (Options.simAccuracy >= 3 && vehicleState.WaitTime < MaxPriorityWaitTime))
                                    {
                                        vehicleState.WaitTime++;
#if DEBUG
                                        if (debug)
                                        {
                                            Log._Debug($"Vehicle {vehicleId}: Setting JunctionTransitState to STOP (wait)");
                                        }
#endif
                                        vehicleState.JunctionTransitState = VehicleJunctionTransitState.Stop;

                                        if (speed <= TrafficPriority.maxYieldVelocity || Options.simAccuracy <= 2)
                                        {
                                            if (Options.simAccuracy >= 4)
                                            {
                                                vehicleState.JunctionTransitState = VehicleJunctionTransitState.Leave;
                                            }
                                            else
                                            {
                                                hasIncomingCars = TrafficPriority.HasIncomingVehiclesWithHigherPriority(vehicleId, ref vehicleData, ref prevPos, ref position);
#if DEBUG
                                                if (debug)
                                                {
                                                    Log._Debug($"Vehicle {vehicleId}: hasIncomingCars: {hasIncomingCars}");
                                                }
#endif

                                                if (hasIncomingCars)
                                                {
                                                    maxSpeed = 0f;
                                                    return(false);
                                                }
                                                else
                                                {
#if DEBUG
                                                    if (debug)
                                                    {
                                                        Log._Debug($"Vehicle {vehicleId}: Setting JunctionTransitState to LEAVE (no incoming cars)");
                                                    }
#endif
                                                    vehicleState.JunctionTransitState = VehicleJunctionTransitState.Leave;
                                                }
                                            }
                                        }
                                        else
                                        {
#if DEBUG
                                            if (debug)
                                            {
                                                Log._Debug($"Vehicle {vehicleId}: Vehicle has not yet reached yield speed (reduce {speed} by {vehicleState.ReduceSpeedByValueToYield})");
                                            }
#endif

                                            // vehicle has not yet reached yield speed
                                            maxSpeed = TrafficPriority.maxYieldVelocity;
                                            return(false);
                                        }
                                    }
                                    else
                                    {
#if DEBUG
                                        if (debug)
                                        {
                                            Log._Debug($"Vehicle {vehicleId}: Setting JunctionTransitState to LEAVE (max wait timeout)");
                                        }
#endif
                                        vehicleState.JunctionTransitState = VehicleJunctionTransitState.Leave;
                                    }
                                    break;

                                case SegmentEnd.PriorityType.Main:
                                case SegmentEnd.PriorityType.None:
#if DEBUG
                                    if (debug)
                                    {
                                        Log._Debug($"Vehicle {vehicleId}: MAIN sign. waittime={vehicleState.WaitTime}");
                                    }
#endif
                                    maxSpeed = 0f;

                                    if (Options.simAccuracy == 4)
                                    {
                                        return(true);
                                    }

                                    if (Options.simAccuracy <= 2 || (Options.simAccuracy == 3 && vehicleState.WaitTime < MaxPriorityWaitTime))
                                    {
                                        vehicleState.WaitTime++;
#if DEBUG
                                        if (debug)
                                        {
                                            Log._Debug($"Vehicle {vehicleId}: Setting JunctionTransitState to STOP (wait)");
                                        }
#endif
                                        vehicleState.JunctionTransitState = VehicleJunctionTransitState.Stop;

                                        hasIncomingCars = TrafficPriority.HasIncomingVehiclesWithHigherPriority(vehicleId, ref vehicleData, ref prevPos, ref position);
#if DEBUG
                                        if (debug)
                                        {
                                            Log._Debug($"hasIncomingCars: {hasIncomingCars}");
                                        }
#endif

                                        if (hasIncomingCars)
                                        {
                                            return(false);
                                        }
#if DEBUG
                                        if (debug)
                                        {
                                            Log._Debug($"Vehicle {vehicleId}: Setting JunctionTransitState to LEAVE (no conflicting car)");
                                        }
#endif
                                        vehicleState.JunctionTransitState = VehicleJunctionTransitState.Leave;
                                    }
                                    return(true);
                                }
                            }
                            else if (speed <= TrafficPriority.maxStopVelocity)
                            {
                                // vehicle is not moving. reset allowance to leave junction
#if DEBUG
                                if (debug)
                                {
                                    Log._Debug($"Vehicle {vehicleId}: Setting JunctionTransitState from LEAVE to BLOCKED (speed to low)");
                                }
#endif
                                vehicleState.JunctionTransitState = VehicleJunctionTransitState.Blocked;

                                maxSpeed = 0f;
                                return(false);
                            }
                        }
                    }
                }
            } catch (Exception e) {
                Log.Error($"Error occured in MayChangeSegment: {e.ToString()}");
            }
            maxSpeed = 0f;             // maxSpeed should be set by caller
            return(true);
        }