Add sound event for brake overcharging

Author: peternewell

Source/Orts.Simulation/Common/Events.cs

@@ -240,6 +240,10 @@ public enum Event
         HeatingOn,
         AirConditioningOff,
         AirConditioningOn,
+
+        OverchargeBrakingOn,
+        OverchargeBrakingOff,
+
     }
 
     public static class Events
@@ -496,6 +500,9 @@ public static Event From(bool mstsBinEnabled, Source source, int eventID)
                         case 234: return Event.AirConditioningOn;
                         case 235: return Event.AirConditioningOff;
 
+                        case 250: return Event.OverchargeBrakingOn;
+                        case 251: return Event.OverchargeBrakingOff;
+
                         default: return 0;
                     }
                 case Source.MSTSCrossing:

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

@@ -353,6 +353,7 @@ public float OdometerM
         public float DynamicBrakeDelayS;
         public bool DynamicBrakeAutoBailOff;
         public bool UsingRearCab;
+        public bool BrakeOverchargeSoundOn = false;
 
         protected bool DynamicBrakeBlended; // dynamic brake blending is currently active
         protected bool DynamicBrakeBlendingEnabled; // dynamic brake blending is configured

Source/Orts.Simulation/Simulation/RollingStocks/SubSystems/Brakes/MSTS/AirSinglePipe.cs

@@ -608,6 +608,23 @@ public override void Update(float elapsedClockSeconds)
                 }
                 prevCylPressurePSI = AutoCylPressurePSI;
                 prevBrakePipePressurePSI = BrakeLine1PressurePSI;
+
+                var lead = Car as MSTSLocomotive;
+
+                if (lead != null && Car.WagonType == MSTSWagon.WagonTypes.Engine)
+                {
+                    if (lead.TrainBrakeController.TrainBrakeControllerState == ControllerState.Overcharge && !lead.BrakeOverchargeSoundOn)
+                    {
+                        Car.SignalEvent(Event.OverchargeBrakingOn);
+                        lead.BrakeOverchargeSoundOn = true;
+                    }
+                    else if (lead.TrainBrakeController.TrainBrakeControllerState != ControllerState.Overcharge && lead.BrakeOverchargeSoundOn)
+                    {
+                        Car.SignalEvent(Event.OverchargeBrakingOff);
+                        lead.BrakeOverchargeSoundOn = false;
+                    }
+                }
+
             }
             SoundTriggerCounter = SoundTriggerCounter + elapsedClockSeconds;
         }