Reduce allocations in TT pre-run

Author: pzgulyas

Source/Orts.Simulation/Simulation/AIs/AITrain.cs

@@ -129,6 +129,8 @@ public enum AI_START_MOVEMENT
         public static float minStopDistanceM = 3.0f;           // minimum clear distance for stopping at signal in station
         public static float signalApproachDistanceM = 20.0f;   // final approach to signal
 
+        private readonly List<ObjectItemInfo> processedList = new List<ObjectItemInfo>(); // internal processing list for CheckSignalObjects()
+
 #if WITH_PATH_DEBUG
         //  Only for EnhancedActCompatibility
         public string currentAIState = "";
@@ -1164,10 +1166,12 @@ public void CheckSignalObjects()
             }
 
             float validSpeed = AllowedMaxSpeedMpS;
-            List<ObjectItemInfo> processedList = new List<ObjectItemInfo>();
+            processedList.Clear();
 
-            foreach (ObjectItemInfo thisInfo in SignalObjectItems.Where(item => !item.speed_isWarning))
+            foreach (ObjectItemInfo thisInfo in SignalObjectItems)
             {
+                if (thisInfo.speed_isWarning)
+                    continue;
 
                 // check speedlimit
                 if (CheckTrain)

Source/Orts.Simulation/Simulation/Physics/Train.cs

@@ -96,6 +96,7 @@ public TrainCar LastCar
         }
         public Traveller RearTDBTraveller;               // positioned at the back of the last car in the train
         public Traveller FrontTDBTraveller;              // positioned at the front of the train by CalculatePositionOfCars
+        Traveller CalculatorTraveller;            // CalculatePositionOfCars uses it for the calculations
         public float Length;                             // length of train from FrontTDBTraveller to RearTDBTraveller
         public float MassKg;                             // weight of the train
         public float SpeedMpS;                           // meters per second +ve forward, -ve when backing
@@ -420,6 +421,8 @@ public enum END_AUTHORITY
 
         public bool nextRouteReady = false;                             // indication to activity.cs that a reversal has taken place
 
+        readonly List<int[]> sectionList = new List<int[]>(); // internally used in UpdateSectionState()
+
         // Deadlock Info : 
         // list of sections where deadlock begins
         // per section : list with trainno and end section
@@ -4378,7 +4381,9 @@ public void CalculatePositionOfCars(float elapsedTime, float distance)
 
             // TODO : check if train moved back into previous section
 
-            var traveller = new Traveller(RearTDBTraveller);
+            CalculatorTraveller = CalculatorTraveller ?? new Traveller(RearTDBTraveller);
+            var traveller = CalculatorTraveller;
+            traveller.Copy(RearTDBTraveller);
             // The traveller location represents the back of the train.
             var length = 0f;
 
@@ -4453,7 +4458,7 @@ public void CalculatePositionOfCars(float elapsedTime, float distance)
                 car.UpdateFreightAnimationDiscretePositions();
             }
 
-            FrontTDBTraveller = traveller;
+            (FrontTDBTraveller, CalculatorTraveller) = (CalculatorTraveller, FrontTDBTraveller);
             Length = length;
             travelled += distance;
         } // CalculatePositionOfCars
@@ -6521,7 +6526,7 @@ public void ObtainRequiredActions(int backward)
         public void UpdateSectionState(int backward)
         {
 
-            List<int[]> sectionList = new List<int[]>();
+            sectionList.Clear();
 
             int lastIndex = PreviousPosition[0].RouteListIndex;
             int presentIndex = PresentPosition[0].RouteListIndex;
@@ -20025,6 +20030,7 @@ public RoughReversalInfo(int subPathIndex, float reverseReversalOffset, int reve
 
         public class DistanceTravelledActions : LinkedList<DistanceTravelledItem>
         {
+            readonly List<DistanceTravelledItem> itemList = new List<DistanceTravelledItem>();
 
             //================================================================================================//
             //
@@ -20111,7 +20117,7 @@ public void InsertClearSection(float distance, int sectionIndex)
 
             public List<DistanceTravelledItem> GetActions(float distance)
             {
-                List<DistanceTravelledItem> itemList = new List<DistanceTravelledItem>();
+                itemList.Clear();
 
                 bool itemsCollected = false;
                 LinkedListNode<DistanceTravelledItem> nextNode = this.First;
@@ -20136,7 +20142,7 @@ public List<DistanceTravelledItem> GetActions(float distance)
 
             public List<DistanceTravelledItem> GetAuxActions(Train thisTrain, float distance)
             {
-                List<DistanceTravelledItem> itemList = new List<DistanceTravelledItem>();
+                itemList.Clear();
                 LinkedListNode<DistanceTravelledItem> nextNode = this.First;
 
                 while (nextNode != null)
@@ -20159,7 +20165,7 @@ public List<DistanceTravelledItem> GetAuxActions(Train thisTrain, float distance
 
             public List<DistanceTravelledItem> GetActions(float distance, Type reqType)
             {
-                List<DistanceTravelledItem> itemList = new List<DistanceTravelledItem>();
+                itemList.Clear();
 
                 bool itemsCollected = false;
                 LinkedListNode<DistanceTravelledItem> nextNode = this.First;

Source/Orts.Simulation/Simulation/RollingStocks/MSTSWagon.cs

@@ -1865,7 +1865,7 @@ public override void Update(float elapsedClockSeconds)
 
                 AuxWagonType = "AuxiliaryTender";
             }
-            else
+            else if (AuxWagonType == "")
             {
                 AuxWagonType = WagonType.ToString();
             }

Source/Orts.Simulation/Simulation/RollingStocks/SubSystems/PowerSupplies/LocomotivePowerSupply.cs

@@ -55,11 +55,15 @@ public float ElectricTrainSupplyPowerW
         {
             get
             {
-                return Train.Cars.OfType<MSTSWagon>()
-                    .Where(wagon => wagon.PassengerCarPowerSupply != null)
-                    .Where(wagon => wagon.PassengerCarPowerSupply.ElectricTrainSupplyConnectedLocomotives.Contains(Locomotive))
-                    .Select(wagon => wagon.PassengerCarPowerSupply.ElectricTrainSupplyPowerW / wagon.PassengerCarPowerSupply.ElectricTrainSupplyConnectedLocomotives.Count())
-                    .Sum();
+                float result = 0;
+                foreach (var car in Train.Cars)
+                {
+                    if (car == null) continue;
+                    if (!(car is MSTSWagon wagon)) continue;
+                    if (!(wagon.PassengerCarPowerSupply?.ElectricTrainSupplyConnectedLocomotives.Contains(Locomotive) ?? false)) continue;
+                    result += wagon.PassengerCarPowerSupply.ElectricTrainSupplyPowerW / wagon.PassengerCarPowerSupply.ElectricTrainSupplyConnectedLocomotives.Count();
+                }
+                return result;
             }
         }
 

Source/Orts.Simulation/Simulation/Signalling/SignalObject.cs

@@ -138,9 +138,11 @@ public enum Permission
 
         public bool CallOnEnabled = false;      // set if signal script file uses CallOn functionality
 
+        private readonly List<int> passedSections = new List<int>();
         private readonly List<int> SectionsWithAlternativePath = new List<int>();
         private readonly List<int> SectionsWithAltPathSet = new List<int>();
         private readonly static List<int> sectionsInRoute = new List<int>();
+        private static readonly ObjectSpeedInfo DefaultSpeedInfo = new ObjectSpeedInfo(-1, -1, false, false, 0, false);
 
         public bool enabled
         {
@@ -907,11 +909,11 @@ public MstsSignalAspect this_sig_lr(SignalFunction function, ref bool sigfound)
         public ObjectSpeedInfo this_sig_speed(SignalFunction function)
         {
             var sigAsp = MstsSignalAspect.STOP;
-            var set_speed = new ObjectSpeedInfo(-1, -1, false, false, 0, false);
+            var set_speed = DefaultSpeedInfo;
 
-            foreach (SignalHead sigHead in SignalHeads.Where(sigHead => sigHead.Function == function))
+            foreach (SignalHead sigHead in SignalHeads)
             {
-                if (sigHead.state >= sigAsp && sigHead.CurrentSpeedInfo != null)
+                if (sigHead.Function == function && sigHead.state >= sigAsp && sigHead.CurrentSpeedInfo != null)
                 {
                     sigAsp = sigHead.state;
                     set_speed = sigHead.CurrentSpeedInfo;
@@ -1293,7 +1295,7 @@ public bool route_set(int req_mainnode, uint req_jnnode)
                 int sectionIndex = -1;
                 bool passedTrackJn = false;
 
-                List<int> passedSections = new List<int>();
+                passedSections.Clear();
                 passedSections.Add(thisSection.Index);
 
                 routeset = req_mainnode == thisSection.OriginalIndex;

Source/Orts.Simulation/Simulation/Traveller.cs

@@ -47,8 +47,8 @@ public enum TravellerDirection : byte
         // experimentally to match MSTS's 'capture range'.
         const float MaximumCenterlineOffset = 2.5f;
 
-        readonly TrackSectionsFile TSectionDat;
-        readonly TrackNode[] TrackNodes;
+        TrackSectionsFile TSectionDat;
+        TrackNode[] TrackNodes;
         TravellerDirection direction = TravellerDirection.Forward;
         float trackOffset; // Offset into track (vector) section; meters for straight sections, radians for curved sections.
         TrackNode trackNode;
@@ -333,8 +333,6 @@ public Traveller(TrackSectionsFile tSectionDat, TrackNode[] trackNodes, TrackNod
         public Traveller(Traveller copy)
         {
             if (copy == null) throw new ArgumentNullException("copy");
-            TSectionDat = copy.TSectionDat;
-            TrackNodes = copy.TrackNodes;
             Copy(copy);
         }
 
@@ -600,8 +598,10 @@ private static bool InitTrackSectionSucceeded(Traveller traveller, WorldLocation
 
 
 
-        void Copy(Traveller copy)
+        public void Copy(Traveller copy)
         {
+            TSectionDat = copy.TSectionDat;
+            TrackNodes = copy.TrackNodes;
             locationSet = copy.locationSet;
             location.TileX = copy.location.TileX;
             location.TileZ = copy.location.TileZ;