Merge pull request #1050 from twpol/refactor/train-car-junction-detection

refactor: TrainCar junction detection

Author: cjakeman

Source/Orts.Simulation/Simulation/RollingStocks/MSTSLocomotive.cs

@@ -3108,7 +3108,7 @@ public virtual void UpdateWaterTroughRefill(float elapsedClockSeconds, float abs
                     Simulator.Confirmer.Message(ConfirmLevel.Error, Simulator.Catalog.GetString("Scoop is broken, can't refill"));
                     RefillingFromTrough = false;
                 }
-                else if (IsOverJunction())
+                else if (IsOverSwitch || IsOverCrossover)
                 {
                     if (!ScoopIsBroken) // Only display message first time scoop is broken
                     {
@@ -3118,7 +3118,7 @@ public virtual void UpdateWaterTroughRefill(float elapsedClockSeconds, float abs
                     RefillingFromTrough = false;
                     SignalEvent(Event.WaterScoopBroken);
                 }
-                else if (!IsOverTrough())
+                else if (!IsOverTrough)
                 {
                     if (!WaterScoopOverTroughFlag)
                     {
@@ -3163,7 +3163,7 @@ public virtual void UpdateWaterTroughRefill(float elapsedClockSeconds, float abs
                 }
 
             }
-            else if (HasWaterScoop && MSTSWagon.RefillProcess.OkToRefill == true && IsOverTrough())// water scoop has been raised, stop water filling
+            else if (HasWaterScoop && MSTSWagon.RefillProcess.OkToRefill == true && IsOverTrough)// water scoop has been raised, stop water filling
             {
                 MSTSWagon.RefillProcess.OkToRefill = false;
                 MSTSWagon.RefillProcess.ActivePickupObjectUID = 0;
@@ -3234,7 +3234,7 @@ public virtual void UpdateWaterTroughRefill(float elapsedClockSeconds, float abs
                 WaterScoopInputAmountL = 0;
                 WaterScoopVelocityMpS = 0;
 
-                if (!IsOverTrough()) // Only reset once train moves off the trough
+                if (!IsOverTrough) // Only reset once train moves off the trough
                 {
                     WaterScoopTotalWaterL = 0.0f; // Reset amount of water picked up by water sccop.
                 }

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

@@ -3525,7 +3525,7 @@ private void UpdateSpecialEffects(float elapsedClockSeconds)
                     }
 
                     // Water scoop spray effects control - always on when scoop over trough, regardless of whether above minimum speed or not
-                    if (ProcessWaterEffects && LocomotiveParameters.IsWaterScoopDown && IsOverTrough() && AbsSpeedMpS > 0.1)
+                    if (ProcessWaterEffects && LocomotiveParameters.IsWaterScoopDown && IsOverTrough && AbsSpeedMpS > 0.1)
                     {
                         float SpeedRatio = AbsSpeedMpS / MpS.FromMpH(100); // Ratio to reduce water disturbance with speed - an arbitary value of 100mph has been chosen as the reference
 

Source/Orts.Simulation/Simulation/RollingStocks/TrainCar.cs

@@ -1,4 +1,4 @@
-// COPYRIGHT 2009 - 2022 by the Open Rails project.
+// COPYRIGHT 2009 - 2022 by the Open Rails project.
 // 
 // This file is part of Open Rails.
 // 
@@ -2872,6 +2872,8 @@ public void ComputePosition(Traveller traveler, bool backToFront, float elapsedT
                     p.FindCenterLine();
                 }
             }
+
+            UpdatePositionFlags();
         }
 
         #region Traveller-based updates
@@ -3091,140 +3093,67 @@ private void AddVibrations(float factor)
         }
         #endregion
 
-        // TODO These three fields should be in the TrainCarViewer.
-        public int TrackSoundType = 0;
-        public WorldLocation TrackSoundLocation = WorldLocation.None;
-        public float TrackSoundDistSquared = 0;
-
+        public bool IsOverSwitch { get; private set; }
+        public bool IsOverCrossover { get; private set; }
+        public bool IsOverTrough { get; private set; }
 
-        /// <summary>
-        /// Checks if traincar is over trough. Used to check if refill possible
-        /// </summary>
-        /// <returns> returns true if car is over trough</returns>
-
-        public bool IsOverTrough()
+        void UpdatePositionFlags()
         {
-            var isOverTrough = false;
-            // start at front of train
-            int thisSectionIndex = Train.PresentPosition[0].TCSectionIndex;
-            if (thisSectionIndex < 0) return isOverTrough;
-            float thisSectionOffset = Train.PresentPosition[0].TCOffset;
-            int thisSectionDirection = Train.PresentPosition[0].TCDirection;
+            // Position flags can only change when we're moving!
+            if (Train == null || AbsSpeedMpS < 0.01f) return;
 
+            // Calculate the position of the ends of this car relative to the REAR of the train
+            var rearOffsetM = Train.PresentPosition[1].TCOffset;
+            for (var i = Train.Cars.IndexOf(this) + 1; i < Train.Cars.Count; i++)
+                rearOffsetM += Train.Cars[i - 1].CouplerSlackM + Train.Cars[i - 1].GetCouplerZeroLengthM() + Train.Cars[i].CarLengthM;
+            var frontOffsetM = rearOffsetM + CarLengthM;
 
-            float usedCarLength = CarLengthM;
-            float processedCarLength = 0;
-            bool validSections = true;
+            var isOverSwitch = false;
+            var isOverCrossover = false;
+            var isOverTrough = false;
 
-            while (validSections)
+            // Scan through the track sections forwards from the REAR of the train (`Train.PresentPosition[1]`),
+            // stopping as soon as we've passed this car (`checkedM`) or run out of track (`currentPin.Link`)
+            var checkedM = 0f;
+            var lastPin = new TrPin { Link = -1, Direction = -1 };
+            var currentPin = new TrPin { Link = Train.PresentPosition[1].TCSectionIndex, Direction = Train.PresentPosition[1].TCDirection };
+            while (checkedM <= frontOffsetM && currentPin.Link != -1)
             {
-                TrackCircuitSection thisSection = Train.signalRef.TrackCircuitList[thisSectionIndex];
-                isOverTrough = false;
+                var section = Simulator.Signals.TrackCircuitList[currentPin.Link];
 
-                // car spans sections
-                if ((CarLengthM - processedCarLength) > thisSectionOffset)
+                // Does this car overlap this track section?
+                if (checkedM <= frontOffsetM && rearOffsetM <= checkedM + section.Length)
                 {
-                    usedCarLength = thisSectionOffset - processedCarLength;
-                }
-
-                // section has troughs
-                if (thisSection.TroughInfo != null)
-                {
-                    foreach (TrackCircuitSection.troughInfoData[] thisTrough in thisSection.TroughInfo)
+                    if (section.CircuitType == TrackCircuitSection.TrackCircuitType.Junction) isOverSwitch = true;
+                    if (section.CircuitType == TrackCircuitSection.TrackCircuitType.Crossover) isOverCrossover = true;
+                    if (section.TroughInfo != null)
                     {
-                        float troughStartOffset = thisTrough[thisSectionDirection].TroughStart;
-                        float troughEndOffset = thisTrough[thisSectionDirection].TroughEnd;
-
-                        if (troughStartOffset > 0 && troughStartOffset > thisSectionOffset)      // start of trough is in section beyond present position - cannot be over this trough nor any following
+                        foreach (var troughs in section.TroughInfo)
                         {
-                            return isOverTrough;
-                        }
-
-                        if (troughEndOffset > 0 && troughEndOffset < (thisSectionOffset - usedCarLength)) // beyond end of trough, test next
-                        {
-                            continue;
-                        }
-
-                        if (troughStartOffset <= 0 || troughStartOffset < (thisSectionOffset - usedCarLength)) // start of trough is behind
-                        {
-                            isOverTrough = true;
-                            return isOverTrough;
+                            var trough = troughs[currentPin.Direction];
+                            // Start and end are -1 if the trough extends beyond this section
+                            var troughStart = trough.TroughStart < 0 ? 0 : trough.TroughStart;
+                            var troughEnd = trough.TroughEnd < 0 ? section.Length : trough.TroughEnd;
+                            if (checkedM + troughStart <= frontOffsetM && rearOffsetM <= checkedM + troughEnd) isOverTrough = true;
                         }
                     }
                 }
-                // tested this section, any need to go beyond?
+                checkedM += section.Length;
 
-                processedCarLength += usedCarLength;
-                {
-                    // go back one section
-                    int thisSectionRouteIndex = Train.ValidRoute[0].GetRouteIndexBackward(thisSectionIndex, Train.PresentPosition[0].RouteListIndex);
-                    if (thisSectionRouteIndex >= 0)
-                    {
-                        thisSectionIndex = thisSectionRouteIndex;
-                        thisSection = Train.signalRef.TrackCircuitList[thisSectionIndex];
-                        thisSectionOffset = thisSection.Length;  // always at end of next section
-                        thisSectionDirection = Train.ValidRoute[0][thisSectionRouteIndex].Direction;
-                    }
-                    else // ran out of train
-                    {
-                        validSections = false;
-                    }
-                }
+                var nextPin = section.GetNextActiveLink(currentPin.Direction, lastPin.Link);
+                lastPin = currentPin;
+                currentPin = nextPin;
             }
-            return isOverTrough;
-        }
 
-        /// <summary>
-        /// Checks if traincar is over junction or crossover. Used to check if water scoop breaks
-        /// </summary>
-        /// <returns> returns true if car is over junction</returns>
-
-        public bool IsOverJunction()
-        {
-
-            // To Do - This identifies the start of the train, but needs to be further refined to work for each carriage.
-            var isOverJunction = false;
-            // start at front of train
-            int thisSectionIndex = Train.PresentPosition[0].TCSectionIndex;
-            float thisSectionOffset = Train.PresentPosition[0].TCOffset;
-            int thisSectionDirection = Train.PresentPosition[0].TCDirection;
-
-
-            float usedCarLength = CarLengthM;
-
-            if (Train.PresentPosition[0].TCSectionIndex != Train.PresentPosition[1].TCSectionIndex)
-            {
-                try
-                {
-                    var copyOccupiedTrack = Train.OccupiedTrack.ToArray();
-                    foreach (var thisSection in copyOccupiedTrack)
-                    {
-
-                        //                    Trace.TraceInformation(" Track Section - Index {0} Ciruit Type {1}", thisSectionIndex, thisSection.CircuitType);
-
-                        if (thisSection.CircuitType == TrackCircuitSection.TrackCircuitType.Junction || thisSection.CircuitType == TrackCircuitSection.TrackCircuitType.Crossover)
-                        {
-
-                            // train is on a switch; let's see if car is on a switch too
-                            WorldLocation switchLocation = TileLocation(Simulator.TDB.TrackDB.TrackNodes[thisSection.OriginalIndex].UiD);
-                            var distanceFromSwitch = WorldLocation.GetDistanceSquared(WorldPosition.WorldLocation, switchLocation);
-                            if (distanceFromSwitch < CarLengthM * CarLengthM + Math.Min(SpeedMpS * 3, 150))
-                            {
-                                isOverJunction = true;
-                                return isOverJunction;
-                            }
-                        }
-                    }
-                }
-                catch
-                {
-
-                }
-            }
-
-            return isOverJunction;
+            IsOverSwitch = isOverSwitch;
+            IsOverCrossover = isOverCrossover;
+            IsOverTrough = isOverTrough;
         }
 
+        // TODO These three fields should be in the TrainCarViewer.
+        public int TrackSoundType = 0;
+        public WorldLocation TrackSoundLocation = WorldLocation.None;
+        public float TrackSoundDistSquared = 0;
 
         public static WorldLocation TileLocation(UiD uid)
         {

Source/RunActivity/Viewer3D/Popups/TrainDrivingWindow.cs

@@ -1187,7 +1187,7 @@ void AddSeparator() => AddLabel(new ListLabel
                 }
                 else if (locomotive.IsWaterScoopDown && !locomotive.ScoopIsBroken)
                 {
-                    waterScoopIndicator = Viewer.Catalog.GetString("Down") + (locomotive.IsOverTrough() ? ColorCode[Color.Cyan] : ColorCode[Color.Orange]);
+                    waterScoopIndicator = Viewer.Catalog.GetString("Down") + (locomotive.IsOverTrough ? ColorCode[Color.Cyan] : ColorCode[Color.Orange]);
                     waterScoopKey = Symbols.ArrowToRight + ColorCode[Color.Yellow];
                 }
                 else

Source/RunActivity/Viewer3D/Sound.cs

@@ -395,32 +395,8 @@ public bool UpdateCarOnSwitchAndCurve()
 
                     var CarBehind = Car.Train.Cars[CarNo + CarIncr];
                     var carPreviouslyOnSwitch = CarOnSwitch;
-                    CarOnSwitch = false;
-                    if (Car.Train.PresentPosition[0].TCSectionIndex != Car.Train.PresentPosition[1].TCSectionIndex)
-                    {
-                        try
-                        {
-                            var copyOccupiedTrack = Car.Train.OccupiedTrack.ToArray();
-                            foreach (var thisSection in copyOccupiedTrack)
-                            {
-                                if (thisSection.CircuitType == TrackCircuitSection.TrackCircuitType.Junction || thisSection.CircuitType == TrackCircuitSection.TrackCircuitType.Crossover)
-                                {
-                                    // train is on a switch; let's see if car is on a switch too
-                                    WorldLocation switchLocation = UidLocation(Viewer.Simulator.TDB.TrackDB.TrackNodes[thisSection.OriginalIndex].UiD);
-                                    var distanceFromSwitch = WorldLocation.GetDistanceSquared(Car.WorldPosition.WorldLocation, switchLocation);
-                                    if (distanceFromSwitch < Car.CarLengthM * Car.CarLengthM + Math.Min(Car.SpeedMpS * 3, 150))
-                                    {
-                                        CarOnSwitch = true;
-                                        break;
-                                    }
-                                }
-                            }
-                        }
-                        catch
-                        {
+                    CarOnSwitch = Car.IsOverSwitch || Car.IsOverCrossover;
 
-                        }
-                    }
                     // here check for curve
                     var carPreviouslyOnCurve = CarOnCurve;
                     CarOnCurve = false;

Source/RunActivity/Viewer3D/WebServices/TrainDrivingDisplay.cs

@@ -729,7 +729,7 @@ void AddSeparator() => AddLabel(new ListLabel
                 }
                 else if (locomotive.WaterScoopDown && !locomotive.ScoopIsBroken)
                 {
-                    waterScoopIndicator = Viewer.Catalog.GetString("Down") + (locomotive.IsOverTrough() ? ColorCode[Color.Cyan] : ColorCode[Color.Orange]);
+                    waterScoopIndicator = Viewer.Catalog.GetString("Down") + (locomotive.IsOverTrough ? ColorCode[Color.Cyan] : ColorCode[Color.Orange]);
                     waterScoopKey = Symbols.ArrowToRight + ColorCode[Color.Yellow];
                 }
                 else