(svn r20434) [1.0] -Backport from trunk:

- Fix: [NoAI] Clarify the documentation for AIBaseStation::GetLocation (r20238)
- Fix: Do not spend cash when building a statue fails [FS#3985] (r20227)
- Fix: [NewGRF] Vehicle var FE bit 6 did return incorrect values for new railtypes (r20175)

src/ai/api/ai_basestation.hpp

@@ -64,7 +64,9 @@ public:
 	 * Get the current location of a basestation.
 	 * @param station_id The basestation to get the location of.
 	 * @pre IsValidBaseStation(station_id).
-	 * @return The tile the basestation is currently on.
+	 * @return The tile the basestation sign above it.
+	 * @note The tile is not necessarily a station tile (and if it is, it could also belong to another station).
+	 * @see AITileList_StationType.
 	 */
 	static TileIndex GetLocation(StationID station_id);
 

src/lang/english.txt

@@ -3399,6 +3399,7 @@ STR_ERROR_NO_SPACE_FOR_TOWN                                     :{WHITE}... ther
 STR_ERROR_TOWN_EXPAND_WARN_NO_ROADS                             :{WHITE}The town will not build roads. You can enable building of roads via Advanced Settings->Economy->Towns.
 STR_ERROR_ROAD_WORKS_IN_PROGRESS                                :{WHITE}Road works in progress
 STR_ERROR_TOWN_CAN_T_DELETE                                     :{WHITE}Can't delete this town...{}A station or depot is referring to the town or a town owned tile can't be removed
+STR_ERROR_STATUE_NO_SUITABLE_PLACE                              :{WHITE}... there is no suitable place for a statue in the center of this town
 
 # Industry related errors
 STR_ERROR_CAN_T_GENERATE_INDUSTRIES                             :{WHITE}Can't generate industries...

src/newgrf_engine.cpp

@@ -694,11 +694,10 @@ static uint32 VehicleGetVariable(const ResolverObject *object, byte variable, by
 				const Train *u = t->IsWagon() && HasBit(t->vehicle_flags, VRF_POWEREDWAGON) ? t->First() : t;
 				RailType railtype = GetRailType(v->tile);
 				bool powered = t->IsEngine() || (t->IsWagon() && HasBit(t->vehicle_flags, VRF_POWEREDWAGON));
-				bool has_power = powered && HasPowerOnRail(u->railtype, railtype);
+				bool has_power = HasPowerOnRail(u->railtype, railtype);
-				bool is_electric = powered && u->railtype == RAILTYPE_ELECTRIC;
 
-				if (has_power) SetBit(modflags, 5);
+				if (powered && has_power) SetBit(modflags, 5);
-				if (is_electric && !has_power) SetBit(modflags, 6);
+				if (powered && !has_power) SetBit(modflags, 6);
 				if (HasBit(t->flags, VRF_TOGGLE_REVERSE)) SetBit(modflags, 8);
 			}
 			if (HasBit(v->vehicle_flags, VF_BUILT_AS_PROTOTYPE)) SetBit(modflags, 10);

src/town_cmd.cpp

@@ -2335,23 +2335,33 @@ const byte _town_action_costs[TACT_COUNT] = {
 	2, 4, 9, 35, 48, 53, 117, 175
 };
 
-static void TownActionAdvertiseSmall(Town *t)
+static CommandCost TownActionAdvertiseSmall(Town *t, DoCommandFlag flags)
 {
+	if (flags & DC_EXEC) {
 		ModifyStationRatingAround(t->xy, _current_company, 0x40, 10);
+	}
+	return CommandCost();
 }
 
-static void TownActionAdvertiseMedium(Town *t)
+static CommandCost TownActionAdvertiseMedium(Town *t, DoCommandFlag flags)
 {
+	if (flags & DC_EXEC) {
 		ModifyStationRatingAround(t->xy, _current_company, 0x70, 15);
+	}
+	return CommandCost();
 }
 
-static void TownActionAdvertiseLarge(Town *t)
+static CommandCost TownActionAdvertiseLarge(Town *t, DoCommandFlag flags)
 {
+	if (flags & DC_EXEC) {
 		ModifyStationRatingAround(t->xy, _current_company, 0xA0, 20);
+	}
+	return CommandCost();
 }
 
-static void TownActionRoadRebuild(Town *t)
+static CommandCost TownActionRoadRebuild(Town *t, DoCommandFlag flags)
 {
+	if (flags & DC_EXEC) {
 		t->road_build_months = 6;
 
 		char company_name[MAX_LENGTH_COMPANY_NAME_BYTES];
@@ -2363,9 +2373,17 @@ static void TownActionRoadRebuild(Town *t)
 		SetDParamStr(1, cn);
 
 		AddNewsItem(STR_NEWS_ROAD_REBUILDING, NS_GENERAL, NR_TOWN, t->index, NR_NONE, UINT32_MAX, cn);
+	}
+	return CommandCost();
 }
 
-static bool DoBuildStatueOfCompany(TileIndex tile, TownID town_id)
+/**
+ * Search callback function for TownActionBuildStatue.
+ * @param tile Tile on which to perform the search.
+ * @param user_data Unused.
+ * @return Result of the test.
+ */
+static bool SearchTileForStatue(TileIndex tile, void *user_data)
 {
 	/* Statues can be build on slopes, just like houses. Only the steep slopes is a no go. */
 	if (IsSteepSlope(GetTileSlope(tile, NULL))) return false;
@@ -2380,66 +2398,66 @@ static bool DoBuildStatueOfCompany(TileIndex tile, TownID town_id)
 
 	CompanyID old = _current_company;
 	_current_company = OWNER_NONE;
-	CommandCost r = DoCommand(tile, 0, 0, DC_EXEC, CMD_LANDSCAPE_CLEAR);
+	CommandCost r = DoCommand(tile, 0, 0, DC_NONE, CMD_LANDSCAPE_CLEAR);
 	_current_company = old;
 
 	if (r.Failed()) return false;
 
-	MakeStatue(tile, _current_company, town_id);
-	MarkTileDirtyByTile(tile);
-
 	return true;
 }
 
-/**
- * Search callback function for TownActionBuildStatue
- * @param tile on which to perform the search
- * @param user_data The town_id for which we want a statue
- * @return the result of the test
- */
-static bool SearchTileForStatue(TileIndex tile, void *user_data)
-{
-	TownID *town_id = (TownID *)user_data;
-	return DoBuildStatueOfCompany(tile, *town_id);
-}
-
 /**
  * Perform a 9x9 tiles circular search from the center of the town
  * in order to find a free tile to place a statue
  * @param t town to search in
+ * @param flags Used to check if the statue must be built or not.
+ * @return Empty cost or an error.
  */
-static void TownActionBuildStatue(Town *t)
+static CommandCost TownActionBuildStatue(Town *t, DoCommandFlag flags)
 {
 	TileIndex tile = t->xy;
-
+	if (CircularTileSearch(&tile, 9, SearchTileForStatue, NULL)) {
-	if (CircularTileSearch(&tile, 9, SearchTileForStatue, &t->index)) {
+		if (flags & DC_EXEC) {
-		SetBit(t->statues, _current_company); // Once found and built, "inform" the Town
+			DoCommand(tile, 0, 0, DC_EXEC, CMD_LANDSCAPE_CLEAR);
+			MakeStatue(tile, _current_company, t->index);
+			SetBit(t->statues, _current_company); // Once found and built, "inform" the Town.
+			MarkTileDirtyByTile(tile);
 		}
+		return CommandCost();
+	}
+	return_cmd_error(STR_ERROR_STATUE_NO_SUITABLE_PLACE);
 }
 
-static void TownActionFundBuildings(Town *t)
+static CommandCost TownActionFundBuildings(Town *t, DoCommandFlag flags)
 {
+	if (flags & DC_EXEC) {
 		/* Build next tick */
 		t->grow_counter = 1;
 		/* If we were not already growing */
 		SetBit(t->flags, TOWN_IS_FUNDED);
 		/* And grow for 3 months */
 		t->fund_buildings_months = 3;
+	}
+	return CommandCost();
 }
 
-static void TownActionBuyRights(Town *t)
+static CommandCost TownActionBuyRights(Town *t, DoCommandFlag flags)
 {
 	/* Check if it's allowed to by the rights */
-	if (!_settings_game.economy.exclusive_rights) return;
+	if (!_settings_game.economy.exclusive_rights) return CMD_ERROR;
 
+	if (flags & DC_EXEC) {
 		t->exclusive_counter = 12;
 		t->exclusivity = _current_company;
 
 		ModifyStationRatingAround(t->xy, _current_company, 130, 17);
+	}
+	return CommandCost();
 }
 
-static void TownActionBribe(Town *t)
+static CommandCost TownActionBribe(Town *t, DoCommandFlag flags)
 {
+	if (flags & DC_EXEC) {
 		if (Chance16(1, 14)) {
 			/* set as unwanted for 6 months */
 			t->unwanted[_current_company] = 6;
@@ -2467,9 +2485,11 @@ static void TownActionBribe(Town *t)
 		} else {
 			ChangeTownRating(t, RATING_BRIBE_UP_STEP, RATING_BRIBE_MAXIMUM, DC_EXEC);
 		}
+	}
+	return CommandCost();
 }
 
-typedef void TownActionProc(Town *t);
+typedef CommandCost TownActionProc(Town *t, DoCommandFlag flags);
 static TownActionProc * const _town_action_proc[] = {
 	TownActionAdvertiseSmall,
 	TownActionAdvertiseMedium,
@@ -2545,8 +2565,10 @@ CommandCost CmdDoTownAction(TileIndex tile, DoCommandFlag flags, uint32 p1, uint
 
 	CommandCost cost(EXPENSES_OTHER, _price[PR_TOWN_ACTION] * _town_action_costs[p2] >> 8);
 
+	CommandCost ret = _town_action_proc[p2](t, flags);
+	if (ret.Failed()) return ret;
+
 	if (flags & DC_EXEC) {
-		_town_action_proc[p2](t);
 		SetWindowDirty(WC_TOWN_AUTHORITY, p1);
 	}