Improve performance of train breakdown detection

src/saveload/afterload.cpp

@@ -3137,6 +3137,14 @@ bool AfterLoadGame()
 			}
 		}
 	}
+	if (SlXvIsFeatureMissing(XSLFI_CONSIST_BREAKDOWN_FLAG)) {
+		Train *v;
+		FOR_ALL_TRAINS(v) {
+			if (v->breakdown_ctr != 0 && (v->IsEngine() || v->IsMultiheaded())) {
+				SetBit(v->First()->flags, VRF_CONSIST_BREAKDOWN);
+			}
+		}
+	}
 
 	/* The road owner of standard road stops was not properly accounted for. */
 	if (IsSavegameVersionBefore(172)) {

src/saveload/extended_ver_sl.cpp

@@ -60,6 +60,7 @@ const SlxiSubChunkInfo _sl_xv_sub_chunk_infos[] = {
 	{ XSLFI_TOWN_CARGO_ADJ,         XSCF_IGNORABLE_UNKNOWN,   2,   2, "town_cargo_adj",            NULL, NULL, NULL        },
 	{ XSLFI_SIG_TUNNEL_BRIDGE,      XSCF_NULL,                7,   7, "signal_tunnel_bridge",      NULL, NULL, "XBSS"      },
 	{ XSLFI_IMPROVED_BREAKDOWNS,    XSCF_NULL,                6,   6, "improved_breakdowns",       NULL, NULL, NULL        },
+	{ XSLFI_CONSIST_BREAKDOWN_FLAG, XSCF_NULL,                1,   1, "consist_breakdown_flag",    NULL, NULL, NULL        },
 	{ XSLFI_TT_WAIT_IN_DEPOT,       XSCF_NULL,                1,   1, "tt_wait_in_depot",          NULL, NULL, NULL        },
 	{ XSLFI_AUTO_TIMETABLE,         XSCF_NULL,                4,   4, "auto_timetables",           NULL, NULL, NULL        },
 	{ XSLFI_VEHICLE_REPAIR_COST,    XSCF_NULL,                2,   2, "vehicle_repair_cost",       NULL, NULL, NULL        },

src/saveload/extended_ver_sl.h

@@ -34,6 +34,7 @@ enum SlXvFeatureIndex {
 	XSLFI_TOWN_CARGO_ADJ,                         ///< Town cargo adjustment patch
 	XSLFI_SIG_TUNNEL_BRIDGE,                      ///< Signals on tunnels and bridges
 	XSLFI_IMPROVED_BREAKDOWNS,                    ///< Improved breakdowns patch
+	XSLFI_CONSIST_BREAKDOWN_FLAG,                 ///< Consist breakdown flag
 	XSLFI_TT_WAIT_IN_DEPOT,                       ///< Timetabling waiting time in depot patch
 	XSLFI_AUTO_TIMETABLE,                         ///< Auto timetables and separation patch
 	XSLFI_VEHICLE_REPAIR_COST,                    ///< Vehicle repair costs patch

src/train.h

@@ -44,6 +44,7 @@ enum VehicleRailFlags {
 	VRF_BEYOND_PLATFORM_END           = 16,
 	VRF_NOT_YET_IN_PLATFORM           = 17,
 	VRF_ADVANCE_IN_PLATFORM           = 18,
+	VRF_CONSIST_BREAKDOWN             = 19,///< one or more vehicles in this consist have a breakdown of some sort (breakdown_ctr != 0)
 
 	VRF_IS_BROKEN = (1 << VRF_BREAKDOWN_POWER) | (1 << VRF_BREAKDOWN_SPEED) | (1 << VRF_BREAKDOWN_STOPPED), ///< Bitmask of all flags that indicate a broken train (braking is not included)
 };

src/train_cmd.cpp

@@ -4770,7 +4770,7 @@ static bool TrainLocoHandler(Train *v, bool mode)
 	}
 
 	/* train is broken down? */
-	if (HandlePossibleBreakdowns(v)) return true;
+	if (HasBit(v->flags, VRF_CONSIST_BREAKDOWN) && HandlePossibleBreakdowns(v)) return true;
 
 	if (HasBit(v->flags, VRF_REVERSING) && v->cur_speed == 0) {
 		ReverseTrainDirection(v);
@@ -5548,6 +5548,7 @@ void TrainRoadVehicleCrashBreakdown(Vehicle *v)
 {
 	Train *t = Train::From(v)->First();
 	t->breakdown_ctr = 2;
+	SetBit(t->flags, VRF_CONSIST_BREAKDOWN);
 	t->breakdown_delay = 255;
 	t->breakdown_type = BREAKDOWN_RV_CRASH;
 	t->breakdown_severity = 0;

src/vehicle.cpp

@@ -183,6 +183,7 @@ void VehicleServiceInDepot(Vehicle *v)
 		if (!(Train::From(v)->IsEngine()) && !(Train::From(v)->IsRearDualheaded())) return;
 		ClrBit(Train::From(v)->flags, VRF_NEED_REPAIR);
 		ClrBit(Train::From(v)->flags, VRF_HAS_HIT_RV);
+		ClrBit(Train::From(v)->flags, VRF_CONSIST_BREAKDOWN);
 		Train::From(v)->critical_breakdown_count = 0;
 		const RailVehicleInfo *rvi = &e->u.rail;
 		v->vcache.cached_max_speed = rvi->max_speed;
@@ -1715,6 +1716,7 @@ void CheckVehicleBreakdown(Vehicle *v)
 	if ((uint32) (0xffff - v->reliability) * _settings_game.difficulty.vehicle_breakdowns * chance > GB(r1, 0, 24) * 10) {
 		uint32 r2 = Random();
 		v->breakdown_ctr = GB(r1, 24, 6) + 0xF;
+		if (v->type == VEH_TRAIN) SetBit(Train::From(v)->First()->flags, VRF_CONSIST_BREAKDOWN);
 		v->breakdown_delay = GB(r2, 0, 7) + 0x80;
 		v->breakdown_chance = 0;
 		DetermineBreakdownType(v, r2);