Simplify derailing logic, derail reason enum

- The `TMoverParameters::derail()` function has been renamed to `::Derail()`, with a capital D.
- All derail events now use that function.
  - Simplified and unified the logic behind different derail types.
  - The `dtrack_freerail` track type is now slightly increasing the chance of derailing on a tight curve, as it was the intention.
- A new `DerailReason` enum has been created which holds all derail types.
- The `DerailReason` field in the `TMoverParameters` class has been removed.
  - This was a transient field which is not necessary anymore.
  - The logging functionality as such has been moved from `DynObj.cpp` to `Mover.cpp`.

McZapkie/MOVER.h

@@ -122,7 +122,18 @@ static int const dtrain_loaddestroyed = 32;/*dla wagonow*/
 static int const dtrain_axle = 64;
 static int const dtrain_out = 128;         /*wykolejenie*/
 static int const dtrain_pantograph = 256;	/*polamanie pantografu*/
-										   /*wagi prawdopodobienstwa dla funkcji FuzzyLogic*/
+
+/*przyczyny wykolejenia*/
+enum DerailReason {
+	NONE = 0,
+	END_OF_TRACK = 1,      // Ra: powód wykolejenia: brak szyn
+	TOO_HIGH_SPEED = 2,    // Ra: powód wykolejenia: przewrócony na łuku
+	GAUGE_MISMATCH = 3,    // Ra: powód wykolejenia: za szeroki tor
+	WRONG_TRACK_TYPE = 4,  // Ra: powód wykolejenia: nieodpowiednia trajektoria
+	COLLISION = 5,         //     powód wykolejenia: zderzenie z innym pojazdem
+};
+
+/*wagi prawdopodobienstwa dla funkcji FuzzyLogic*/
 #define p_elengproblem  (1e-02)
 #define p_elengdamage  (1e-01)
 #define p_coupldmg  (2e-03)
@@ -1590,7 +1601,6 @@ class TMoverParameters
 
 	int DamageFlag = 0; // kombinacja bitowa stalych dtrain_* }
 	int EngDmgFlag = 0; // kombinacja bitowa stalych usterek}
-	int DerailReason = 0; // przyczyna wykolejenia
 
 	// EndSignalsFlag: byte;  {ABu 060205: zmiany - koncowki: 1/16 - swiatla prz/tyl, 2/31 - blachy prz/tyl}
 	// HeadSignalsFlag: byte; {ABu 060205: zmiany - swiatla: 1/2/4 - przod, 16/32/63 - tyl}
@@ -1832,7 +1842,7 @@ public:
 	int DettachStatus(int ConnectNo);
 	bool Dettach(int ConnectNo);
     void damage_coupler( int const End );
-    void derail( int const Reason );
+    void Derail(DerailReason Reason);
 	bool DirectionForward();
     bool DirectionBackward( void );/*! kierunek ruchu*/
     bool EIMDirectionChangeAllow( void ) const;

McZapkie/Mover.cpp

@@ -1252,10 +1252,10 @@ void TMoverParameters::CollisionDetect(int const End, double const dt)
                 }
 
                 if( velocitydifference > safevelocitylimit * ( TotalMass / othervehicle->TotalMass ) ) {
-                    derail( 5 );
+                    Derail(COLLISION);
                 }
                 if( velocitydifference > safevelocitylimit * ( othervehicle->TotalMass / TotalMass ) ) {
-                    othervehicle->derail( 5 );
+                    othervehicle->Derail(COLLISION);
                 }
             }
         }
@@ -1318,24 +1318,31 @@ TMoverParameters::damage_coupler( int const End ) {
     WriteLog( "Bad driving: " + Name + " broke a coupler" );
 }
 
-void 
-TMoverParameters::derail( int const Reason ) {
-
+void TMoverParameters::Derail( DerailReason const Reason ) {
     if( SetFlag( DamageFlag, dtrain_out ) ) {
-
-        DerailReason = Reason; // TODO: enum derail causes
         EventFlag = true;
         MainSwitch( false, range_t::local );
 
         AccS *= 0.65;
         V *= 0.65;
+    	RunningShape.R = 0;
         if( Vel < 5.0 ) {
             // HACK: prevent permanent axle spin in static vehicle after a collision
             nrot = 0.0;
             SlippingWheels = false;
         }
 
-        WriteLog( "Bad driving: " + Name + " derailed" );
+    	// Print a message in the log.
+    	if (Reason == END_OF_TRACK)
+    		ErrorLog("Bad driving: " + Name + " derailed due to end of track");
+    	else if (Reason == TOO_HIGH_SPEED)
+    		ErrorLog("Bad driving: " + Name + " derailed due to too high speed");
+    	else if (Reason == GAUGE_MISMATCH)
+    		ErrorLog("Bad dynamic: " + Name + " derailed due to track width"); // błąd w scenerii
+    	else if (Reason == WRONG_TRACK_TYPE)
+    		ErrorLog("Bad dynamic: " + Name + " derailed due to wrong track type"); // błąd w scenerii
+    	else if (Reason == COLLISION)
+			WriteLog("Bad driving: " + Name + " derailed"); // This reason also generates its own message in `TMoverParameters::CollisionDetect()`
     }
 }
 
@@ -1436,42 +1443,17 @@ double TMoverParameters::ComputeMovement(double dt, double dt1, const TTrackShap
         // wykolejanie na luku oraz z braku szyn
         if (TestFlag(CategoryFlag, 1))
         {
-            if (FuzzyLogic((AccN / g) * (1.0 + 0.1 * (Track.DamageFlag && dtrack_freerail)),
-                           TrackW / Dim.H, 1) ||
-                TestFlag(Track.DamageFlag, dtrack_norail))
-                if (SetFlag(DamageFlag, dtrain_out))
-                {
-                    EventFlag = true;
-                    MainSwitch( false, range_t::local );
-                    RunningShape.R = 0;
-                    if (TestFlag(Track.DamageFlag, dtrack_norail))
-                        DerailReason = 1; // Ra: powód wykolejenia: brak szyn
-                    else
-                        DerailReason = 2; // Ra: powód wykolejenia: przewrócony na łuku
-                }
+        	if (TestFlag(Track.DamageFlag, dtrack_norail))
+        		Derail(END_OF_TRACK);
+            if (FuzzyLogic((AccN / g) * (1.0 + 0.1 * (Track.DamageFlag & dtrack_freerail)), TrackW / Dim.H, 1))
+            	Derail(TOO_HIGH_SPEED);
             // wykolejanie na poszerzeniu toru
             if (FuzzyLogic(abs(Track.Width - TrackW), TrackW / 10.0, 1))
-                if (SetFlag(DamageFlag, dtrain_out))
-                {
-                    EventFlag = true;
-                    MainSwitch( false, range_t::local );
-                    RunningShape.R = 0;
-                    DerailReason = 3; // Ra: powód wykolejenia: za szeroki tor
-                }
+            	Derail(GAUGE_MISMATCH);
         }
         // wykolejanie wkutek niezgodnosci kategorii toru i pojazdu
         if (!TestFlag(RunningTrack.CategoryFlag, CategoryFlag))
-            if (SetFlag(DamageFlag, dtrain_out))
-            {
-                EventFlag = true;
-                MainSwitch( false, range_t::local );
-                DerailReason = 4; // Ra: powód wykolejenia: nieodpowiednia trajektoria
-            }
-        if( ( true == TestFlag( DamageFlag, dtrain_out ) )
-         && ( Vel < 1.0 ) ) {
-            V = 0.0;
-            AccS = 0.0;
-        }
+        	Derail(WRONG_TRACK_TYPE);
 
         // dL:=(V+AccS*dt/2)*dt;                                      
         // przyrost dlugosci czyli przesuniecie

vehicle/DynObj.cpp

@@ -4265,27 +4265,6 @@ bool TDynamicObject::Update(double dt, double dt1)
 		MoverParameters->InactiveCabPantsCheck = false;
 	}
 
-
-    if (MoverParameters->DerailReason > 0)
-    {
-        switch (MoverParameters->DerailReason)
-        {
-        case 1:
-            ErrorLog("Bad driving: " + asName + " derailed due to end of track");
-            break;
-        case 2:
-            ErrorLog("Bad driving: " + asName + " derailed due to too high speed");
-            break;
-        case 3:
-            ErrorLog("Bad dynamic: " + asName + " derailed due to track width");
-            break; // błąd w scenerii
-        case 4:
-            ErrorLog("Bad dynamic: " + asName + " derailed due to wrong track type");
-            break; // błąd w scenerii
-        }
-        MoverParameters->DerailReason = 0; //żeby tylko raz
-    }
-
     if( MoverParameters->LoadStatus ) {
         LoadUpdate(); // zmiana modelu ładunku
     }