Adjacent crossings: add setting (in PATX), add info to SLXI chunk.

src/lang/english.txt

@@ -1703,6 +1703,9 @@ STR_CONFIG_SETTING_REVERSE_AT_SIGNALS_HELPTEXT                  :Allow trains to
 
 STR_CONFIG_SETTING_QUERY_CAPTION                                :{WHITE}Change setting value
 
+STR_CONFIG_SETTING_ADJACENT_CROSSINGS                           :Close adjacent level crossings: {STRING2}
+STR_CONFIG_SETTING_ADJACENT_CROSSINGS_HELPTEXT                  :Closes all adjacent level crossings on parallel tracks whenever one or more is occupied
+
 # Config errors
 STR_CONFIG_ERROR                                                :{WHITE}Error with the configuration file...
 STR_CONFIG_ERROR_ARRAY                                          :{WHITE}... error in array '{RAW_STRING}'

src/saveload/extended_ver_sl.cpp

@@ -45,6 +45,7 @@ std::vector<uint32> _sl_xv_discardable_chunk_ids;           ///< list of chunks
 static const uint32 _sl_xv_slxi_chunk_version = 0;          ///< current version os SLXI chunk
 
 const SlxiSubChunkInfo _sl_xv_sub_chunk_infos[] = {
+	{ XSLFI_ADJACENT_CROSSINGS, XSCF_NULL, 1, 1, "adjacent_crossings", NULL, NULL, NULL },
 	{ XSLFI_NULL, XSCF_NULL, 0, 0, NULL, NULL, NULL, NULL },// This is the end marker
 };
 

src/saveload/extended_ver_sl.h

@@ -21,6 +21,7 @@
  */
 enum SlXvFeatureIndex {
 	XSLFI_NULL                          = 0,      ///< Unused value, to indicate that no extended feature test is in use
+	XSLFI_ADJACENT_CROSSINGS,                     ///< Adjacent level crossings closure patch
 
 	XSLFI_SIZE,                                   ///< Total count of features, including null feature
 };

src/settings_gui.cpp

@@ -1626,6 +1626,7 @@ static SettingsContainer &GetSettingsTree()
 
 			vehicles->Add(new SettingEntry("order.no_servicing_if_no_breakdowns"));
 			vehicles->Add(new SettingEntry("order.serviceathelipad"));
+			vehicles->Add(new SettingEntry("vehicle.adjacent_crossings"));
 		}
 
 		SettingsPage *limitations = main->Add(new SettingsPage(STR_CONFIG_SETTING_LIMITATIONS));

src/settings_type.h

@@ -462,6 +462,7 @@ struct VehicleSettings {
 	byte   extend_vehicle_life;              ///< extend vehicle life by this many years
 	byte   road_side;                        ///< the side of the road vehicles drive on
 	uint8  plane_crashes;                    ///< number of plane crashes, 0 = none, 1 = reduced, 2 = normal
+	bool   adjacent_crossings;               ///< enable closing of adjacent level crossings
 };
 
 /** Settings related to the economy. */

src/table/settings.ini

@@ -2506,6 +2506,16 @@ def      = NULL
 proc     = RedrawScreen
 cat      = SC_BASIC
 
+[SDT_BOOL]
+base     = GameSettings
+var      = vehicle.adjacent_crossings
+guiflags = SGF_NO_NETWORK
+def      = true
+str      = STR_CONFIG_SETTING_ADJACENT_CROSSINGS
+strhelp  = STR_CONFIG_SETTING_ADJACENT_CROSSINGS_HELPTEXT
+cat      = SC_BASIC
+patxname = ""adjacent_crossings.vehicle.adjacent_crossings""
+
 
 ;***************************************************************************
 ; Unsaved setting variables.

src/train_cmd.cpp

@@ -1723,11 +1723,13 @@ void UpdateLevelCrossing(TileIndex tile, bool sound)
 
 	Axis axis = GetCrossingRoadAxis(tile);
 
-	for (TileIndex t = tile; !is_forced && IsLevelCrossingTile(t) && GetCrossingRoadAxis(t) == axis; t = TileAddByDiagDir(t, AxisToDiagDir(GetCrossingRoadAxis(t)))) {
+	if (_settings_game.vehicle.adjacent_crossings) {
-		is_forced |= CheckLevelCrossing(t);
+		for (TileIndex t = tile; !is_forced && IsLevelCrossingTile(t) && GetCrossingRoadAxis(t) == axis; t = TileAddByDiagDir(t, AxisToDiagDir(GetCrossingRoadAxis(t)))) {
-	}
+			is_forced |= CheckLevelCrossing(t);
-	for (TileIndex t = tile; !is_forced && IsLevelCrossingTile(t) && GetCrossingRoadAxis(t) == axis; t = TileAddByDiagDir(t, ReverseDiagDir(AxisToDiagDir(GetCrossingRoadAxis(t))))) {
+		}
-		is_forced |= CheckLevelCrossing(t);
+		for (TileIndex t = tile; !is_forced && IsLevelCrossingTile(t) && GetCrossingRoadAxis(t) == axis; t = TileAddByDiagDir(t, ReverseDiagDir(AxisToDiagDir(GetCrossingRoadAxis(t))))) {
+			is_forced |= CheckLevelCrossing(t);
+		}
 	}
 
 	for (TileIndex t = tile; IsLevelCrossingTile(t) && GetCrossingRoadAxis(t) == axis; t = TileAddByDiagDir(t, AxisToDiagDir(GetCrossingRoadAxis(t)))) {