Only show level crossing overlay sprites on outsides of multi-track crossings

When using both adjacent crossings and safer crossings

src/rail_cmd.cpp

@@ -817,6 +817,7 @@ CommandCost CmdBuildSingleRail(TileIndex tile, DoCommandFlag flags, uint32 p1, u
 					if (flags & DC_EXEC) {
 						MakeRoadCrossing(tile, road_owner, tram_owner, _current_company, (track == TRACK_X ? AXIS_Y : AXIS_X), railtype, roadtype_road, roadtype_tram, GetTownIndex(tile));
 						UpdateLevelCrossing(tile, false);
+						MarkDirtyAdjacentLevelCrossingTilesOnAddRemove(tile, GetCrossingRoadAxis(tile));
 						Company::Get(_current_company)->infrastructure.rail[railtype] += LEVELCROSSING_TRACKBIT_FACTOR;
 						DirtyCompanyInfrastructureWindows(_current_company);
 						if (num_new_road_pieces > 0 && Company::IsValidID(road_owner)) {
@@ -934,6 +935,7 @@ CommandCost CmdRemoveSingleRail(TileIndex tile, DoCommandFlag flags, uint32 p1,
 			}
 
 			if (flags & DC_EXEC) {
+				MarkDirtyAdjacentLevelCrossingTilesOnAddRemove(tile, GetCrossingRoadAxis(tile));
 				if (v != nullptr) FreeTrainTrackReservation(v);
 
 				owner = GetTileOwner(tile);

src/road_cmd.cpp

@@ -808,6 +808,8 @@ static CommandCost RemoveRoad(TileIndex tile, DoCommandFlag flags, RoadBits piec
 			}
 
 			if (flags & DC_EXEC) {
+				MarkDirtyAdjacentLevelCrossingTilesOnAddRemove(tile, GetCrossingRoadAxis(tile));
+
 				/* A full diagonal road tile has two road bits. */
 				UpdateCompanyRoadInfrastructure(existing_rt, GetRoadOwner(tile, rtt), -2);
 
@@ -1111,6 +1113,7 @@ CommandCost CmdBuildRoad(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32
 				MakeRoadCrossing(tile, company, company, GetTileOwner(tile), roaddir, GetRailType(tile), rtt == RTT_ROAD ? rt : INVALID_ROADTYPE, (rtt == RTT_TRAM) ? rt : INVALID_ROADTYPE, p2);
 				SetCrossingReservation(tile, reserved);
 				UpdateLevelCrossing(tile, false);
+				MarkDirtyAdjacentLevelCrossingTilesOnAddRemove(tile, GetCrossingRoadAxis(tile));
 				if (RoadLayoutChangeNotificationEnabled(true)) NotifyRoadLayoutChangedIfTileNonLeaf(tile, rtt, GetCrossingRoadBits(tile));
 				if (rtt == RTT_ROAD) {
 					UpdateRoadCachedOneWayStatesAroundTile(tile);
@@ -2235,7 +2238,47 @@ static void DrawTile_Road(TileInfo *ti, DrawTileProcParams params)
 				SpriteID rail = GetCustomRailSprite(rti, ti->tile, RTSG_CROSSING) + axis;
 				DrawGroundSprite(rail, pal);
 
+
+				if (_settings_game.vehicle.safer_crossings && _settings_game.vehicle.adjacent_crossings) {
+					const Axis axis = GetCrossingRoadAxis(ti->tile);
+					const DiagDirection dir1 = AxisToDiagDir(axis);
+					const DiagDirection dir2 = ReverseDiagDir(dir1);
+					uint adjacent_diagdirs = 0;
+					for (DiagDirection dir : { dir1, dir2 }) {
+						const TileIndex t = TileAddByDiagDir(ti->tile, dir);
+						if (t < MapSize() && IsLevelCrossingTile(t) && GetCrossingRoadAxis(t) == axis) {
+							SetBit(adjacent_diagdirs, dir);
+						}
+					}
+
+					switch (adjacent_diagdirs) {
+						case 0:
 							DrawRailTileSeq(ti, &_crossing_layout, TO_CATENARY, rail, 0, PAL_NONE);
+							break;
+
+						case (1 << DIAGDIR_NE):
+							DrawRailTileSeq(ti, &_crossing_layout_SW, TO_CATENARY, rail, 0, PAL_NONE);
+							break;
+
+						case (1 << DIAGDIR_SE):
+							DrawRailTileSeq(ti, &_crossing_layout_NW, TO_CATENARY, rail, 0, PAL_NONE);
+							break;
+
+						case (1 << DIAGDIR_SW):
+							DrawRailTileSeq(ti, &_crossing_layout_NE, TO_CATENARY, rail, 0, PAL_NONE);
+							break;
+
+						case (1 << DIAGDIR_NW):
+							DrawRailTileSeq(ti, &_crossing_layout_SE, TO_CATENARY, rail, 0, PAL_NONE);
+							break;
+
+						default:
+							/* Show no sprites */
+							break;
+					}
+				} else {
+					DrawRailTileSeq(ti, &_crossing_layout, TO_CATENARY, rail, 0, PAL_NONE);
+				}
 			} else if (draw_pbs || tram_rti != nullptr || road_rti->UsesOverlay()) {
 				/* Add another rail overlay, unless there is only the base road sprite. */
 				PaletteID pal = draw_pbs ? PALETTE_CRASH : PAL_NONE;

src/road_func.h

@@ -155,6 +155,7 @@ RoadTypes GetRoadTypes(bool introduces);
 RoadTypes AddDateIntroducedRoadTypes(RoadTypes current, Date date);
 
 void UpdateLevelCrossing(TileIndex tile, bool sound = true, bool force_close = false);
+void MarkDirtyAdjacentLevelCrossingTilesOnAddRemove(TileIndex tile, Axis road_axis);
 bool IsCrossingOccupiedByRoadVehicle(TileIndex t);
 
 void UpdateRoadCachedOneWayStatesAroundTile(TileIndex tile);

src/table/road_land.h

@@ -53,6 +53,54 @@ static const DrawTileSprites _crossing_layout = {
 	{0, PAL_NONE}, _crossing_layout_ALL
 };
 
+static const DrawTileSeqStruct _crossing_layout_SW_ALL[] = {
+	//TILE_SEQ_LINE(2, PAL_NONE,  0,  0, 3, 3)
+	//TILE_SEQ_LINE(4, PAL_NONE,  0, 13, 3, 3)
+	TILE_SEQ_LINE(6, PAL_NONE, 13,  0, 3, 3)
+	TILE_SEQ_LINE(8, PAL_NONE, 13, 13, 3, 3)
+	TILE_SEQ_END()
+};
+
+static const DrawTileSprites _crossing_layout_SW = {
+	{0, PAL_NONE}, _crossing_layout_SW_ALL
+};
+
+static const DrawTileSeqStruct _crossing_layout_NW_ALL[] = {
+	TILE_SEQ_LINE(2, PAL_NONE,  0,  0, 3, 3)
+	//TILE_SEQ_LINE(4, PAL_NONE,  0, 13, 3, 3)
+	TILE_SEQ_LINE(6, PAL_NONE, 13,  0, 3, 3)
+	//TILE_SEQ_LINE(8, PAL_NONE, 13, 13, 3, 3)
+	TILE_SEQ_END()
+};
+
+static const DrawTileSprites _crossing_layout_NW = {
+	{0, PAL_NONE}, _crossing_layout_NW_ALL
+};
+
+static const DrawTileSeqStruct _crossing_layout_NE_ALL[] = {
+	TILE_SEQ_LINE(2, PAL_NONE,  0,  0, 3, 3)
+	TILE_SEQ_LINE(4, PAL_NONE,  0, 13, 3, 3)
+	//TILE_SEQ_LINE(6, PAL_NONE, 13,  0, 3, 3)
+	//TILE_SEQ_LINE(8, PAL_NONE, 13, 13, 3, 3)
+	TILE_SEQ_END()
+};
+
+static const DrawTileSprites _crossing_layout_NE = {
+	{0, PAL_NONE}, _crossing_layout_NE_ALL
+};
+
+static const DrawTileSeqStruct _crossing_layout_SE_ALL[] = {
+	//TILE_SEQ_LINE(2, PAL_NONE,  0,  0, 3, 3)
+	TILE_SEQ_LINE(4, PAL_NONE,  0, 13, 3, 3)
+	//TILE_SEQ_LINE(6, PAL_NONE, 13,  0, 3, 3)
+	TILE_SEQ_LINE(8, PAL_NONE, 13, 13, 3, 3)
+	TILE_SEQ_END()
+};
+
+static const DrawTileSprites _crossing_layout_SE = {
+	{0, PAL_NONE}, _crossing_layout_SE_ALL
+};
+
 #undef TILE_SEQ_LINE
 #undef TILE_SEQ_END
 

src/train_cmd.cpp

@@ -2610,6 +2610,20 @@ void UpdateLevelCrossing(TileIndex tile, bool sound, bool force_close)
 	}
 }
 
+void MarkDirtyAdjacentLevelCrossingTilesOnAddRemove(TileIndex tile, Axis road_axis)
+{
+	if (!(_settings_game.vehicle.safer_crossings && _settings_game.vehicle.adjacent_crossings)) return;
+
+	const DiagDirection dir1 = AxisToDiagDir(road_axis);
+	const DiagDirection dir2 = ReverseDiagDir(dir1);
+	for (DiagDirection dir : { dir1, dir2 }) {
+		const TileIndex t = TileAddByDiagDir(tile, dir);
+		if (t < MapSize() && IsLevelCrossingTile(t) && GetCrossingRoadAxis(t) == road_axis) {
+			MarkTileDirtyByTile(t, VMDF_NOT_MAP_MODE);
+		}
+	}
+}
+
 /**
  * Check if the level crossing is occupied by road vehicle(s).
  * @param t The tile to query.