- Make sure we clear the additional railtype bit only for the correct tiles.

- Backup and restore the correct railtype for tiles when newGRFs are reloaded during a game.

(cherry picked from commit f5bf8e69b4fe95519513b934dc1057dc304ce3da)

src/saveload/afterload.cpp

@@ -3217,11 +3217,12 @@ bool AfterLoadGame()
 	// So set it to 0 just in case there was garbage in there.
 	if (SlXvIsFeatureMissing(XSLFI_MORE_RAIL_TYPES)) {
 		for (TileIndex t = 0; t < map_size; t++) {
-			if (_m[t].type == MP_RAILWAY ||
+			if (GetTileType(t) == MP_RAILWAY ||
-					_m[t].type == MP_ROAD ||
+					IsLevelCrossingTile(t) ||
-					_m[t].type == MP_STATION ||
+					IsRailStationTile(t) ||
-					_m[t].type == MP_TUNNELBRIDGE) {
+					IsRailWaypointTile(t) ||
-				SB(_m[t].m1, 7, 1, 0);
+					IsRailTunnelBridgeTile(t)) {
+				ClrBit(_m[t].m1, 7);
 			}
 		}
 	}
@@ -3263,6 +3264,21 @@ bool AfterLoadGame()
  */
 void ReloadNewGRFData()
 {
+	TileIndex map_size = MapSize();
+
+	/* Backup railtype labels for all rail tiles. The railtype info array will be resorted. */
+	std::map<TileIndex, RailTypeLabel> rail_type_label_backups;
+
+	for (TileIndex t = 0; t < map_size; t++) {
+		if (GetTileType(t) == MP_RAILWAY ||
+			IsLevelCrossingTile(t) ||
+			IsRailStationTile(t) ||
+			IsRailWaypointTile(t) ||
+			IsRailTunnelBridgeTile(t)) {
+			rail_type_label_backups[t] = GetRailTypeInfo(GetRailType(t))->label;
+		}
+	}
+
 	/* reload grf data */
 	GfxLoadSprites();
 	LoadStringWidthTable();
@@ -3288,4 +3304,16 @@ void ReloadNewGRFData()
 	MarkWholeScreenDirty();
 	CheckTrainsLengths();
 	AfterLoadTemplateVehiclesUpdateImage();
+
+	/* Restore correct railtype for all rail tiles.*/
+	for (TileIndex t = 0; t < map_size; t++) {
+		if (GetTileType(t) == MP_RAILWAY ||
+			IsLevelCrossingTile(t) ||
+			IsRailStationTile(t) ||
+			IsRailWaypointTile(t) ||
+			IsRailTunnelBridgeTile(t)) {
+			RailType old_type = GetRailTypeByLabel(rail_type_label_backups[t]);
+			SetRailType(t, (old_type == INVALID_RAILTYPE) ? RAILTYPE_RAIL : old_type);
+		}
+	}
 }

src/tunnelbridge_map.h

@@ -14,6 +14,7 @@
 
 #include "bridge_map.h"
 #include "tunnel_map.h"
+#include "cmd_helper.h"
 
 
 /**
@@ -57,6 +58,19 @@ static inline bool HasTunnelBridgeSnowOrDesert(TileIndex t)
 	return HasBit(_me[t].m7, 5);
 }
 
+
+/**
+* Is this a rail bridge or tunnel?
+* @param t the tile that might be a rail bridge or tunnel
+* @return true if and only if this tile is a rail bridge or tunnel
+*/
+static inline bool IsRailTunnelBridgeTile(TileIndex t)
+{
+	TransportType tt = Extract<TransportType, 2, 2>(_m[t].m5);
+
+	return IsTileType(t, MP_TUNNELBRIDGE) && (tt == TRANSPORT_RAIL);
+}
+
 /**
  * Tunnel: Places this tunnel entrance in a snowy or desert area, or takes it out of there.
  * Bridge: Sets whether the bridge ramp lies in a snow or desert area.