Change: Don't apply forbid 90 deg turn settings to ships.

src/lang/english.txt

@@ -1200,8 +1200,8 @@ STR_CONFIG_SETTING_TRAIN_SLOPE_STEEPNESS_HELPTEXT               :Steepness of a
 STR_CONFIG_SETTING_PERCENTAGE                                   :{COMMA}%
 STR_CONFIG_SETTING_ROAD_VEHICLE_SLOPE_STEEPNESS                 :Slope steepness for road vehicles: {STRING2}
 STR_CONFIG_SETTING_ROAD_VEHICLE_SLOPE_STEEPNESS_HELPTEXT        :Steepness of a sloped tile for a road vehicle. Higher values make it more difficult to climb a hill
-STR_CONFIG_SETTING_FORBID_90_DEG                                :Forbid trains and ships from making 90° turns: {STRING2}
-STR_CONFIG_SETTING_FORBID_90_DEG_HELPTEXT                       :90 degree turns occur when a horizontal track is directly followed by a vertical track piece on the adjacent tile, thus making the train turn by 90 degree when traversing the tile edge instead of the usual 45 degrees for other track combinations. This also applies to the turning radius of ships
+STR_CONFIG_SETTING_FORBID_90_DEG                                :Forbid trains from making 90° turns: {STRING2}
+STR_CONFIG_SETTING_FORBID_90_DEG_HELPTEXT                       :90 degree turns occur when a horizontal track is directly followed by a vertical track piece on the adjacent tile, thus making the train turn by 90 degree when traversing the tile edge instead of the usual 45 degrees for other track combinations.
 STR_CONFIG_SETTING_DISTANT_JOIN_STATIONS                        :Allow to join stations not directly adjacent: {STRING2}
 STR_CONFIG_SETTING_DISTANT_JOIN_STATIONS_HELPTEXT               :Allow adding parts to a station without directly touching the existing parts. Needs Ctrl+Click while placing the new parts
 STR_CONFIG_SETTING_INFLATION                                    :Inflation: {STRING2}

src/pathfinder/follow_track.hpp

@@ -474,8 +474,6 @@ typedef CFollowTrackT<TRANSPORT_WATER, Ship,        true > CFollowTrackWater;
 typedef CFollowTrackT<TRANSPORT_ROAD,  RoadVehicle, true > CFollowTrackRoad;
 typedef CFollowTrackT<TRANSPORT_RAIL,  Train,       true > CFollowTrackRail;
 
-typedef CFollowTrackT<TRANSPORT_WATER, Ship,        false> CFollowTrackWaterNo90;
-typedef CFollowTrackT<TRANSPORT_ROAD,  RoadVehicle, false> CFollowTrackRoadNo90;
 typedef CFollowTrackT<TRANSPORT_RAIL,  Train,       false> CFollowTrackRailNo90;
 
 typedef CFollowTrackT<TRANSPORT_RAIL, Train, true,  true > CFollowTrackFreeRail;

src/pathfinder/npf/npf.cpp

@@ -836,7 +836,7 @@ static TrackdirBits GetDriveableTrackdirBits(TileIndex dst_tile, Trackdir src_tr
 	trackdirbits &= TrackdirReachesTrackdirs(src_trackdir);
 
 	/* Filter out trackdirs that would make 90 deg turns for trains */
-	if (_settings_game.pf.forbid_90_deg && (type == TRANSPORT_RAIL || type == TRANSPORT_WATER)) trackdirbits &= ~TrackdirCrossesTrackdirs(src_trackdir);
+	if (_settings_game.pf.forbid_90_deg && type == TRANSPORT_RAIL) trackdirbits &= ~TrackdirCrossesTrackdirs(src_trackdir);
 
 	DEBUG(npf, 6, "After filtering: (%d, %d), possible trackdirs: 0x%X", TileX(dst_tile), TileY(dst_tile), trackdirbits);
 

src/pathfinder/yapf/yapf_road.cpp

@@ -501,11 +501,11 @@ Trackdir YapfRoadVehicleChooseTrack(const RoadVehicle *v, TileIndex tile, DiagDi
 {
 	/* default is YAPF type 2 */
 	typedef Trackdir (*PfnChooseRoadTrack)(const RoadVehicle*, TileIndex, DiagDirection, bool &path_found);
-	PfnChooseRoadTrack pfnChooseRoadTrack = &CYapfRoad2::stChooseRoadTrack; // default: ExitDir, allow 90-deg
+	PfnChooseRoadTrack pfnChooseRoadTrack = &CYapfRoad2::stChooseRoadTrack; // default: ExitDir
 
 	/* check if non-default YAPF type should be used */
 	if (_settings_game.pf.yapf.disable_node_optimization) {
-		pfnChooseRoadTrack = &CYapfRoad1::stChooseRoadTrack; // Trackdir, allow 90-deg
+		pfnChooseRoadTrack = &CYapfRoad1::stChooseRoadTrack; // Trackdir
 	}
 
 	Trackdir td_ret = pfnChooseRoadTrack(v, tile, enterdir, path_found);
@@ -526,7 +526,7 @@ FindDepotData YapfRoadVehicleFindNearestDepot(const RoadVehicle *v, int max_dist
 
 	/* check if non-default YAPF type should be used */
 	if (_settings_game.pf.yapf.disable_node_optimization) {
-		pfnFindNearestDepot = &CYapfRoadAnyDepot1::stFindNearestDepot; // Trackdir, allow 90-deg
+		pfnFindNearestDepot = &CYapfRoadAnyDepot1::stFindNearestDepot; // Trackdir
 	}
 
 	return pfnFindNearestDepot(v, tile, trackdir, max_distance);

src/pathfinder/yapf/yapf_ship.cpp

@@ -224,25 +224,21 @@ struct CYapfShip_TypesT
 	typedef CYapfCostShipT<Types>             PfCost;        // cost provider
 };
 
-/* YAPF type 1 - uses TileIndex/Trackdir as Node key, allows 90-deg turns */
+/* YAPF type 1 - uses TileIndex/Trackdir as Node key */
 struct CYapfShip1 : CYapfT<CYapfShip_TypesT<CYapfShip1, CFollowTrackWater    , CShipNodeListTrackDir> > {};
-/* YAPF type 2 - uses TileIndex/DiagDirection as Node key, allows 90-deg turns */
+/* YAPF type 2 - uses TileIndex/DiagDirection as Node key */
 struct CYapfShip2 : CYapfT<CYapfShip_TypesT<CYapfShip2, CFollowTrackWater    , CShipNodeListExitDir > > {};
-/* YAPF type 3 - uses TileIndex/Trackdir as Node key, forbids 90-deg turns */
-struct CYapfShip3 : CYapfT<CYapfShip_TypesT<CYapfShip3, CFollowTrackWaterNo90, CShipNodeListTrackDir> > {};
 
 /** Ship controller helper - path finder invoker */
 Track YapfShipChooseTrack(const Ship *v, TileIndex tile, DiagDirection enterdir, TrackBits tracks, bool &path_found, ShipPathCache &path_cache)
 {
 	/* default is YAPF type 2 */
 	typedef Trackdir (*PfnChooseShipTrack)(const Ship*, TileIndex, DiagDirection, TrackBits, bool &path_found, ShipPathCache &path_cache);
-	PfnChooseShipTrack pfnChooseShipTrack = CYapfShip2::ChooseShipTrack; // default: ExitDir, allow 90-deg
+	PfnChooseShipTrack pfnChooseShipTrack = CYapfShip2::ChooseShipTrack; // default: ExitDir
 
 	/* check if non-default YAPF type needed */
-	if (_settings_game.pf.forbid_90_deg) {
-		pfnChooseShipTrack = &CYapfShip3::ChooseShipTrack; // Trackdir, forbid 90-deg
-	} else if (_settings_game.pf.yapf.disable_node_optimization) {
-		pfnChooseShipTrack = &CYapfShip1::ChooseShipTrack; // Trackdir, allow 90-deg
+	if (_settings_game.pf.yapf.disable_node_optimization) {
+		pfnChooseShipTrack = &CYapfShip1::ChooseShipTrack; // Trackdir
 	}
 
 	Trackdir td_ret = pfnChooseShipTrack(v, tile, enterdir, tracks, path_found, path_cache);
@@ -256,13 +252,11 @@ bool YapfShipCheckReverse(const Ship *v)
 	TileIndex tile = v->tile;
 
 	typedef bool (*PfnCheckReverseShip)(const Ship*, TileIndex, Trackdir, Trackdir);
-	PfnCheckReverseShip pfnCheckReverseShip = CYapfShip2::CheckShipReverse; // default: ExitDir, allow 90-deg
+	PfnCheckReverseShip pfnCheckReverseShip = CYapfShip2::CheckShipReverse; // default: ExitDir
 
 	/* check if non-default YAPF type needed */
-	if (_settings_game.pf.forbid_90_deg) {
-		pfnCheckReverseShip = &CYapfShip3::CheckShipReverse; // Trackdir, forbid 90-deg
-	} else if (_settings_game.pf.yapf.disable_node_optimization) {
-		pfnCheckReverseShip = &CYapfShip1::CheckShipReverse; // Trackdir, allow 90-deg
+	if (_settings_game.pf.yapf.disable_node_optimization) {
+		pfnCheckReverseShip = &CYapfShip1::CheckShipReverse; // Trackdir
 	}
 
 	bool reverse = pfnCheckReverseShip(v, tile, td, td_rev);

src/ship_cmd.cpp

@@ -474,14 +474,7 @@ static Track ChooseShipTrack(Ship *v, TileIndex tile, DiagDirection enterdir, Tr
 		/* No destination or destination too far, don't invoke pathfinder. */
 		track = TrackBitsToTrack(v->state);
 		if (!IsDiagonalTrack(track)) track = TrackToOppositeTrack(track);
-		if (!HasBit(tracks, track)) {
-			/* Can't continue in same direction so pick first available track. */
-			if (_settings_game.pf.forbid_90_deg) {
-				tracks &= ~TrackCrossesTracks(TrackdirToTrack(v->GetVehicleTrackdir()));
-				if (tracks == TRACK_BIT_NONE) return INVALID_TRACK;
-			}
-			track = FindFirstTrack(tracks);
-		}
+		if (!HasBit(tracks, track)) track = FindFirstTrack(tracks);
 		path_found = false;
 	} else {
 		/* Attempt to follow cached path. */