diff --git a/src/road_cmd.cpp b/src/road_cmd.cpp --- a/src/road_cmd.cpp +++ b/src/road_cmd.cpp @@ -42,6 +42,8 @@ static const uint32 VALID_LEVEL_CROSSING_SLOPES = (M(SLOPE_SEN) | M(SLOPE_ENW) | M(SLOPE_NWS) | M(SLOPE_NS) | M(SLOPE_WSE) | M(SLOPE_EW) | M(SLOPE_FLAT)); #undef M +Foundation GetRoadFoundation(Slope tileh, RoadBits bits); + bool CheckAllowRemoveRoad(TileIndex tile, RoadBits remove, Owner owner, bool *edge_road, RoadType rt) { RoadBits present; @@ -530,6 +532,23 @@ do_clear:; if (IsTileType(tile, MP_ROAD)) { /* Don't put the pieces that already exist */ pieces &= ComplementRoadBits(existing); + + /* Check if new road bits will have the same foundation as other existing road types */ + if (GetRoadTileType(tile) == ROAD_TILE_NORMAL) { + Slope slope = GetTileSlope(tile, NULL); + Foundation found_new = GetRoadFoundation(slope, pieces | existing); + + /* Test if all other roadtypes can be built at that foundation */ + for (RoadType rtest = ROADTYPE_ROAD; rtest < ROADTYPE_END; rtest++) { + if (rtest != rt) { // check only other road types + RoadBits bits = GetRoadBits(tile, rtest); + /* do not check if there are not road bits of given type */ + if (bits != ROAD_NONE && GetRoadFoundation(slope, bits) != found_new) { + return_cmd_error(STR_1000_LAND_SLOPED_IN_WRONG_DIRECTION); + } + } + } + } } cost.AddCost(CountBits(pieces) * _price.build_road);