Add ramp up and down to curve squeal.

Author: peternewell

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

@@ -583,6 +583,9 @@ public Direction Direction
         protected SmoothedData CurveForceFilter = new SmoothedData(0.75f);
         public float CurveForceNFiltered;
 
+        protected SmoothedData CurveSquealAoAmRadFilter = new SmoothedData(0.75f);
+        public float CurveSquealAoAmRadFiltered;
+
         public float TunnelForceN;  // Resistive force due to tunnel, in Newtons
         public float FrictionForceN; // in Newtons ( kg.m/s^2 ) unsigned, includes effects of curvature
         public float BrakeForceN;    // current braking force applied to slow train (Newtons) - will be impacted by wheel/rail friction
@@ -970,6 +973,9 @@ public virtual void Update(float elapsedClockSeconds)
 
             AngleOfAttackmRad = GetAngleofAttackmRad();
 
+            CurveSquealAoAmRadFilter.Update(elapsedClockSeconds, AngleOfAttackmRad);
+            CurveSquealAoAmRadFiltered = CurveSquealAoAmRadFilter.SmoothedValue;
+
             UpdateCurveSpeedLimit(); // call this first as it will provide inputs for the curve force.
             UpdateCurveForce(elapsedClockSeconds);
             UpdateTunnelForce();
@@ -2265,6 +2271,7 @@ public virtual void Save(BinaryWriter outf)
             outf.Write(CarHeatCurrentCompartmentHeatJ);
             outf.Write(CarSteamHeatMainPipeSteamPressurePSI);
             outf.Write(CarHeatCompartmentHeaterOn);
+            outf.Write(CurveSquealAoAmRadFiltered);
         }
 
         // Game restore
@@ -2289,6 +2296,8 @@ public virtual void Restore(BinaryReader inf)
             CarSteamHeatMainPipeSteamPressurePSI = inf.ReadSingle();
             CarHeatCompartmentHeaterOn = inf.ReadBoolean();
             FreightAnimations?.LoadDataList?.Clear();
+            CurveSquealAoAmRadFiltered = inf.ReadSingle();
+            CurveSquealAoAmRadFilter.ForceSmoothValue(CurveSquealAoAmRadFiltered);
         }
 
         //================================================================================================//

Source/RunActivity/Viewer3D/Sound.cs

@@ -1515,7 +1515,7 @@ private float ReadValue(Orts.Formats.Msts.VolumeCurve.Controls control, MSTSWago
                 case Orts.Formats.Msts.VolumeCurve.Controls.Variable3Controlled: return car.Variable3;
                 case Orts.Formats.Msts.VolumeCurve.Controls.BrakeCylControlled: return car.BrakeSystem.GetCylPressurePSI();
                 case Orts.Formats.Msts.VolumeCurve.Controls.CurveForceControlled: return car.CurveForceNFiltered;
-                case Orts.Formats.Msts.VolumeCurve.Controls.AngleofAttackControlled: return car.AngleOfAttackmRad;
+                case Orts.Formats.Msts.VolumeCurve.Controls.AngleofAttackControlled: return car.CurveSquealAoAmRadFiltered;
                 case Orts.Formats.Msts.VolumeCurve.Controls.CarFrictionControlled: return car.Train.WagonCoefficientFriction;
                 default: return 0;
             }