(svn r26889) -Feature: Predict links for station-autorefitting vehicles

src/linkgraph/refresh.cpp

@@ -81,18 +81,21 @@ LinkRefresher::LinkRefresher(Vehicle *vehicle, HopSet *seen_hops, bool allow_mer
 
 /**
  * Handle refit orders by updating capacities and refit_capacities.
- * @param next Order to be processed.
+ * @param refit_cargo Cargo to refit to.
+ * @return True if any vehicle was refit; false if none was.
  */
-void LinkRefresher::HandleRefit(const Order *next)
+bool LinkRefresher::HandleRefit(CargoID refit_cargo)
 {
-	this->cargo = next->GetRefitCargo();
+	this->cargo = refit_cargo;
 	RefitList::iterator refit_it = this->refit_capacities.begin();
+	bool any_refit = false;
 	for (Vehicle *v = this->vehicle; v != NULL; v = v->Next()) {
 		const Engine *e = Engine::Get(v->engine_type);
 		if (!HasBit(e->info.refit_mask, this->cargo)) {
 			++refit_it;
 			continue;
 		}
+		any_refit = true;
 
 		/* Back up the vehicle's cargo type */
 		CargoID temp_cid = v->cargo_type;
@@ -130,6 +133,7 @@ void LinkRefresher::HandleRefit(const Order *next)
 			break; // aircraft have only one vehicle
 		}
 	}
+	return any_refit;
 }
 
 /**
@@ -253,15 +257,20 @@ void LinkRefresher::RefreshLinks(const Order *cur, const Order *next, uint8 flag
 {
 	while (next != NULL) {
 
-		/* If the refit cargo is CT_AUTO_REFIT, we're optimistic and assume the
-		 * cargo will stay the same. The point of this method is to avoid
-		 * deadlocks due to vehicles waiting for cargo that isn't being routed,
-		 * yet. That situation will not occur if the vehicle is actually
-		 * carrying a different cargo in the end. */
-		if ((next->IsType(OT_GOTO_DEPOT) || next->IsType(OT_GOTO_STATION)) &&
-				next->IsRefit() && !next->IsAutoRefit()) {
+		if ((next->IsType(OT_GOTO_DEPOT) || next->IsType(OT_GOTO_STATION)) && next->IsRefit()) {
 			SetBit(flags, WAS_REFIT);
-			this->HandleRefit(next);
+			if (!next->IsAutoRefit()) {
+				this->HandleRefit(next->GetRefitCargo());
+			} else if (!HasBit(flags, IN_AUTOREFIT)) {
+				SetBit(flags, IN_AUTOREFIT);
+				LinkRefresher backup(*this);
+				for (CargoID c = 0; c != NUM_CARGO; ++c) {
+					if (CargoSpec::Get(c)->IsValid() && this->HandleRefit(c)) {
+						this->RefreshLinks(cur, next, flags, num_hops);
+						*this = backup;
+					}
+				}
+			}
 		}
 
 		/* Only reset the refit capacities if the "previous" next is a station,

src/linkgraph/refresh.h

@@ -31,10 +31,11 @@ protected:
 	 * an influence on the next one.
 	 */
 	enum RefreshFlags {
-		USE_NEXT,   ///< There was a conditional jump. Try to use the given next order when looking for a new one.
-		HAS_CARGO,  ///< Consist could leave the last stop where it could interact with cargo carrying cargo (i.e. not an "unload all" + "no loading" order).
-		WAS_REFIT,  ///< Consist was refit since the last stop where it could interact with cargo.
-		RESET_REFIT ///< Consist had a chance to load since the last refit and the refit capacities can be reset.
+		USE_NEXT,     ///< There was a conditional jump. Try to use the given next order when looking for a new one.
+		HAS_CARGO,    ///< Consist could leave the last stop where it could interact with cargo carrying cargo (i.e. not an "unload all" + "no loading" order).
+		WAS_REFIT,    ///< Consist was refit since the last stop where it could interact with cargo.
+		RESET_REFIT,  ///< Consist had a chance to load since the last refit and the refit capacities can be reset.
+		IN_AUTOREFIT, ///< Currently doing an autorefit loop. Ignore the first autorefit order.
 	};
 
 	/**
@@ -92,7 +93,7 @@ protected:
 
 	LinkRefresher(Vehicle *v, HopSet *seen_hops, bool allow_merge, bool is_full_loading);
 
-	void HandleRefit(const Order *next);
+	bool HandleRefit(CargoID refit_cargo);
 	void ResetRefit();
 	void RefreshStats(const Order *cur, const Order *next);
 	const Order *PredictNextOrder(const Order *cur, const Order *next, uint8 flags, uint num_hops = 0);