Codechange: Remove output pointer from GetTileArea(). (#14530)

This simplifies things and removes undocumented type `ETileArea`

src/base_station_base.h

@@ -130,11 +130,10 @@ struct BaseStation : StationPool::PoolItem<&_station_pool> {
 
 	/**
 	 * Get the tile area for a given station type.
-	 * @param ta tile area to fill.
 	 * @param type the type of the area
+	 * @return The tile area.
 	 */
-	virtual void GetTileArea(TileArea *ta, StationType type) const = 0;
+	virtual TileArea GetTileArea(StationType type) const = 0;
-
 
 	/**
 	 * Obtain the length of a platform

src/newgrf_station.cpp

@@ -73,38 +73,36 @@ enum TriggerArea : uint8_t {
 	TA_WHOLE,
 };
 
-struct ETileArea : TileArea {
+/**
-	ETileArea(const BaseStation *st, TileIndex tile, TriggerArea ta)
+ * Get the tile area of a rail station with trigger area type.
-	{
+ * @param st The rail station or rail waypoint.
-		switch (ta) {
+ * @param tile Origin tile.
-			default: NOT_REACHED();
+ * @param ta Trigger area type.
+ * @return The tile area.
+ */
+TileArea GetRailTileArea(const BaseStation *st, TileIndex tile, TriggerArea ta)
+{
+	switch (ta) {
+		default: NOT_REACHED();
 
-			case TA_TILE:
+		case TA_TILE:
-				this->tile = tile;
+			return {tile, 1, 1};
-				this->w    = 1;
-				this->h    = 1;
-				break;
 
-			case TA_PLATFORM: {
+		case TA_PLATFORM: {
-				TileIndex start, end;
+			TileIndex start, end;
-				Axis axis = GetRailStationAxis(tile);
+			Axis axis = GetRailStationAxis(tile);
-				TileIndexDiff delta = TileOffsByAxis(axis);
+			TileIndexDiff delta = TileOffsByAxis(axis);
 
-				for (end = tile; IsRailStationTile(end + delta) && IsCompatibleTrainStationTile(end + delta, tile); end += delta) { /* Nothing */ }
+			for (end = tile; IsRailStationTile(end + delta) && IsCompatibleTrainStationTile(end + delta, tile); end += delta) { /* Nothing */ }
-				for (start = tile; IsRailStationTile(start - delta) && IsCompatibleTrainStationTile(start - delta, tile); start -= delta) { /* Nothing */ }
+			for (start = tile; IsRailStationTile(start - delta) && IsCompatibleTrainStationTile(start - delta, tile); start -= delta) { /* Nothing */ }
 
-				this->tile = start;
+			return TileArea(start, TileX(end) - TileX(start) + 1, TileY(end) - TileY(start) + 1);
-				this->w = TileX(end) - TileX(start) + 1;
-				this->h = TileY(end) - TileY(start) + 1;
-				break;
-			}
-
-			case TA_WHOLE:
-				st->GetTileArea(this, Station::IsExpected(st) ? StationType::Rail : StationType::RailWaypoint);
-				break;
 		}
+
+		case TA_WHOLE:
+			return st->GetTileArea(Station::IsExpected(st) ? StationType::Rail : StationType::RailWaypoint);
 	}
-};
+}
 
 
 /**
@@ -745,9 +743,8 @@ void DeallocateSpecFromStation(BaseStation *st, uint8_t specindex)
 	/* specindex of 0 (default) is never freeable */
 	if (specindex == 0) return;
 
-	ETileArea area = ETileArea(st, INVALID_TILE, TA_WHOLE);
 	/* Check all tiles over the station to check if the specindex is still in use */
-	for (TileIndex tile : area) {
+	for (TileIndex tile : GetRailTileArea(st, INVALID_TILE, TA_WHOLE)) {
 		if (st->TileBelongsToRailStation(tile) && GetCustomStationSpecIndex(tile) == specindex) {
 			return;
 		}
@@ -911,10 +908,9 @@ void TriggerStationAnimation(BaseStation *st, TileIndex trigger_tile, StationAni
 	if (!st->cached_anim_triggers.Test(trigger)) return;
 
 	uint16_t random_bits = Random();
-	ETileArea area = ETileArea(st, trigger_tile, tas[static_cast<size_t>(trigger)]);
 
 	/* Check all tiles over the station to check if the specindex is still in use */
-	for (TileIndex tile : area) {
+	for (TileIndex tile : GetRailTileArea(st, trigger_tile, tas[static_cast<size_t>(trigger)])) {
 		if (st->TileBelongsToRailStation(tile)) {
 			const StationSpec *ss = GetStationSpec(tile);
 			if (ss != nullptr && ss->animation.triggers.Test(trigger)) {
@@ -951,7 +947,6 @@ void TriggerStationRandomisation(BaseStation *st, TileIndex trigger_tile, Statio
 	if (IsValidCargoType(cargo_type) && !HasBit(st->cached_cargo_triggers, cargo_type)) return;
 
 	uint32_t whole_reseed = 0;
-	ETileArea area = ETileArea(st, trigger_tile, tas[static_cast<size_t>(trigger)]);
 
 	/* Bitmask of completely empty cargo types to be matched. */
 	CargoTypes empty_mask{};
@@ -964,7 +959,7 @@ void TriggerStationRandomisation(BaseStation *st, TileIndex trigger_tile, Statio
 	StationRandomTriggers used_random_triggers;
 
 	/* Check all tiles over the station to check if the specindex is still in use */
-	for (TileIndex tile : area) {
+	for (TileIndex tile : GetRailTileArea(st, trigger_tile, tas[static_cast<size_t>(trigger)])) {
 		if (st->TileBelongsToRailStation(tile)) {
 			const StationSpec *ss = GetStationSpec(tile);
 			if (ss == nullptr) continue;

src/pathfinder/pathfinder_func.h

@@ -25,8 +25,7 @@
 inline TileIndex CalcClosestStationTile(StationID station, TileIndex tile, StationType station_type)
 {
 	const BaseStation *st = BaseStation::Get(station);
-	TileArea ta;
+	TileArea ta = st->GetTileArea(station_type);
-	st->GetTileArea(&ta, station_type);
 
 	/* If the rail station is (temporarily) not present, use the station sign to drive near the station */
 	if (ta.tile == INVALID_TILE) return st->xy;

src/pathfinder/yapf/yapf_ship_regions.cpp

@@ -184,9 +184,7 @@ public:
 		if (v->current_order.IsType(OT_GOTO_STATION)) {
 			StationID station_id = v->current_order.GetDestination().ToStationID();
 			const BaseStation *station = BaseStation::Get(station_id);
-			TileArea tile_area;
+			for (const auto &tile : station->GetTileArea(StationType::Dock)) {
-			station->GetTileArea(&tile_area, StationType::Dock);
-			for (const auto &tile : tile_area) {
 				if (IsDockingTile(tile) && IsShipDestinationTile(tile, station_id)) {
 					pf.AddOrigin(GetWaterRegionPatchInfo(tile));
 				}

src/station_base.h

@@ -579,7 +579,7 @@ public:
 
 	uint32_t GetNewGRFVariable(const ResolverObject &object, uint8_t variable, uint8_t parameter, bool &available) const override;
 
-	void GetTileArea(TileArea *ta, StationType type) const override;
+	TileArea GetTileArea(StationType type) const override;
 };
 
 /** Iterator to iterate over all tiles belonging to an airport. */

src/station_cmd.cpp

@@ -411,30 +411,15 @@ static Station *GetClosestDeletedStation(TileIndex tile)
 }
 
 
-void Station::GetTileArea(TileArea *ta, StationType type) const
+TileArea Station::GetTileArea(StationType type) const
 {
 	switch (type) {
-		case StationType::Rail:
+		case StationType::Rail: return this->train_station;
-			*ta = this->train_station;
+		case StationType::Airport: return this->airport;
-			return;
+		case StationType::Truck: return this->truck_station;
-
+		case StationType::Bus: return this->bus_station;
-		case StationType::Airport:
-			*ta = this->airport;
-			return;
-
-		case StationType::Truck:
-			*ta = this->truck_station;
-			return;
-
-		case StationType::Bus:
-			*ta = this->bus_station;
-			return;
-
 		case StationType::Dock:
-		case StationType::Oilrig:
+		case StationType::Oilrig: return this->docking_station;
-			*ta = this->docking_station;
-			return;
-
 		default: NOT_REACHED();
 	}
 }

src/waypoint.cpp

@@ -32,23 +32,12 @@ void DrawWaypointSprite(int x, int y, StationClassID station_class, uint16_t sta
 	}
 }
 
-void Waypoint::GetTileArea(TileArea *ta, StationType type) const
+TileArea Waypoint::GetTileArea(StationType type) const
 {
 	switch (type) {
-		case StationType::RailWaypoint:
+		case StationType::RailWaypoint: return this->train_station;
-			*ta = this->train_station;
+		case StationType::RoadWaypoint: return this->road_waypoint_area;
-			return;
+		case StationType::Buoy: return {this->xy, 1, 1};
-
-		case StationType::RoadWaypoint:
-			*ta = this->road_waypoint_area;
-			return;
-
-		case StationType::Buoy:
-			ta->tile = this->xy;
-			ta->w    = 1;
-			ta->h    = 1;
-			break;
-
 		default: NOT_REACHED();
 	}
 }

src/waypoint_base.h

@@ -43,7 +43,7 @@ struct Waypoint final : SpecializedStation<Waypoint, true> {
 
 	uint32_t GetNewGRFVariable(const struct ResolverObject &object, uint8_t variable, uint8_t parameter, bool &available) const override;
 
-	void GetTileArea(TileArea *ta, StationType type) const override;
+	TileArea GetTileArea(StationType type) const override;
 
 	uint GetPlatformLength(TileIndex, DiagDirection) const override
 	{

src/waypoint_gui.cpp

@@ -60,9 +60,7 @@ private:
 			default:
 				NOT_REACHED();
 		}
-		TileArea ta;
+		return this->wp->GetTileArea(type).GetCenterTile();
-		this->wp->GetTileArea(&ta, type);
-		return ta.GetCenterTile();
 	}
 
 public: