(svn r11644) -Codechange: merge some functions from tunnel_map.h and bridge_map.h into tunnelbridge_map.h

24 files changed, 233 insertions, 241 deletions

diff --git a/src/ai/default/default.cpp b/src/ai/default/default.cpp
index e84217ddc..671f6a07e 100644
--- a/src/ai/default/default.cpp
+++ b/src/ai/default/default.cpp
@@ -28,8 +28,10 @@
 #include "../../bridge.h"
 #include "../../date.h"
 #include "../../helpers.hpp"
+#include "../../tunnelbridge_map.h"
 #include "default.h"
 
+
 // remove some day perhaps?
 static uint _ai_service_interval;
 
@@ -2233,7 +2235,7 @@ static bool AiRemoveTileAndGoForward(Player *p)
 		} else {
 			// Check if the bridge points in the right direction.
 			// This is not really needed the first place AiRemoveTileAndGoForward is called.
-			if (DiagDirToAxis(GetBridgeRampDirection(tile)) != (p->ai.cur_dir_a & 1)) return false;
+			if (DiagDirToAxis(GetTunnelBridgeDirection(tile)) != (p->ai.cur_dir_a & 1)) return false;
 
 			tile = GetOtherBridgeEnd(tile);
 
@@ -3733,13 +3735,13 @@ pos_3:
 	} else if (IsTileType(tile, MP_TUNNELBRIDGE)) {
 		if (!IsTileOwner(tile, _current_player) ||
 				!IsBridge(tile) ||
-				GetBridgeTransportType(tile) != TRANSPORT_RAIL) {
+				GetTunnelBridgeTransportType(tile) != TRANSPORT_RAIL) {
 			return;
 		}
 
 		rails = TRACK_BIT_NONE;
 
-		switch (GetBridgeRampDirection(tile)) {
+		switch (GetTunnelBridgeDirection(tile)) {
 			default:
 			case DIAGDIR_NE: goto pos_2;
 			case DIAGDIR_SE: goto pos_3;
diff --git a/src/ai/trolly/pathfinder.cpp b/src/ai/trolly/pathfinder.cpp
index bd243dd31..33383a560 100644
--- a/src/ai/trolly/pathfinder.cpp
+++ b/src/ai/trolly/pathfinder.cpp
@@ -12,8 +12,10 @@
 #include "../../depot.h"
 #include "../../tunnel_map.h"
 #include "../../bridge.h"
+#include "../../tunnelbridge_map.h"
 #include "../ai.h"
 
+
 #define TEST_STATION_NO_DIR 0xFF
 
 // Tests if a station can be build on the given spot
@@ -44,8 +46,8 @@ static bool IsRoad(TileIndex tile)
 		// MP_ROAD, but not a road depot?
 		(IsTileType(tile, MP_ROAD) && !IsTileDepotType(tile, TRANSPORT_ROAD)) ||
 		(IsTileType(tile, MP_TUNNELBRIDGE) && (
-			(IsTunnel(tile) && GetTunnelTransportType(tile) == TRANSPORT_ROAD) ||
-			(IsBridge(tile) && GetBridgeTransportType(tile) == TRANSPORT_ROAD)
+			(IsTunnel(tile) && GetTunnelBridgeTransportType(tile) == TRANSPORT_ROAD) ||
+			(IsBridge(tile) && GetTunnelBridgeTransportType(tile) == TRANSPORT_ROAD)
 		));
 }
 
@@ -235,9 +237,9 @@ static void AyStar_AiPathFinder_GetNeighbours(AyStar *aystar, OpenListNode *curr
 			if (!PathFinderInfo->rail_or_road && IsRoad(atile)) {
 				if (IsTileType(atile, MP_TUNNELBRIDGE)) {
 					if (IsTunnel(atile)) {
-						if (GetTunnelDirection(atile) != i) continue;
+						if (GetTunnelBridgeDirection(atile) != i) continue;
 					} else {
-						if (GetBridgeRampDirection(atile) != i) continue;
+						if (GetTunnelBridgeDirection(atile) != i) continue;
 					}
 				}
 			}
diff --git a/src/bridge_map.cpp b/src/bridge_map.cpp
index 318249a4f..8509f305f 100644
--- a/src/bridge_map.cpp
+++ b/src/bridge_map.cpp
@@ -8,6 +8,7 @@
 #include "bridge.h"
 #include "variables.h"
 #include "landscape.h"
+#include "tunnelbridge_map.h"
 
 
 TileIndex GetBridgeEnd(TileIndex tile, DiagDirection dir)
@@ -17,7 +18,7 @@ TileIndex GetBridgeEnd(TileIndex tile, DiagDirection dir)
 	dir = ReverseDiagDir(dir);
 	do {
 		tile += delta;
-	} while (!IsBridgeTile(tile) || GetBridgeRampDirection(tile) != dir);
+	} while (!IsBridgeTile(tile) || GetTunnelBridgeDirection(tile) != dir);
 
 	return tile;
 }
@@ -38,14 +39,14 @@ TileIndex GetSouthernBridgeEnd(TileIndex t)
 TileIndex GetOtherBridgeEnd(TileIndex tile)
 {
 	assert(IsBridgeTile(tile));
-	return GetBridgeEnd(tile, GetBridgeRampDirection(tile));
+	return GetBridgeEnd(tile, GetTunnelBridgeDirection(tile));
 }
 
 uint GetBridgeHeight(TileIndex t)
 {
 	uint h;
 	Slope tileh = GetTileSlope(t, &h);
-	Foundation f = GetBridgeFoundation(tileh, DiagDirToAxis(GetBridgeRampDirection(t)));
+	Foundation f = GetBridgeFoundation(tileh, DiagDirToAxis(GetTunnelBridgeDirection(t)));
 
 	/* one height level extra for the ramp */
 	return h + TILE_HEIGHT + ApplyFoundationToSlope(f, &tileh);
diff --git a/src/bridge_map.h b/src/bridge_map.h
index b7f24ff83..3a329d93b 100644
--- a/src/bridge_map.h
+++ b/src/bridge_map.h
@@ -64,7 +64,6 @@ static inline bool IsBridgeAbove(TileIndex t)
 	return GB(_m[t].m6, 6, 2) != 0;
 }
 
-
 /**
  * Determines the type of bridge on a tile
  * @param t The tile to analyze
@@ -77,20 +76,6 @@ static inline uint GetBridgeType(TileIndex t)
 	return GB(_m[t].m2, 4, 4);
 }
 
-
-/**
- * Get the direction pointing onto the bridge
- * @param t The tile to analyze
- * @pre IsBridgeTile(t)
- * @return the above mentionned direction
- */
-static inline DiagDirection GetBridgeRampDirection(TileIndex t)
-{
-	assert(IsBridgeTile(t));
-	return (DiagDirection)GB(_m[t].m5, 0, 2);
-}
-
-
 /**
  * Get the axis of the bridge that goes over the tile. Not the axis or the ramp.
  * @param t The tile to analyze
@@ -103,45 +88,6 @@ static inline Axis GetBridgeAxis(TileIndex t)
 	return (Axis)(GB(_m[t].m6, 6, 2) - 1);
 }
 
-
-/**
- * Get the transport type of the bridge's ramp.
- * @param t The ramp tile to analyze
- * @pre IsBridgeTile(t)
- * @return the transport type of the bridge
- */
-static inline TransportType GetBridgeTransportType(TileIndex t)
-{
-	assert(IsBridgeTile(t));
-	return (TransportType)GB(_m[t].m5, 2, 2);
-}
-
-
-/**
- * Does the bridge ramp lie in a snow or desert area?
- * @param t The ramp tile to analyze
- * @pre IsBridgeTile(t)
- * @return true if and only if in a snow or desert area
- */
-static inline bool HasBridgeSnowOrDesert(TileIndex t)
-{
-	assert(IsBridgeTile(t));
-	return HasBit(_m[t].m4, 7);
-}
-
-
-/**
- * Sets whether the bridge ramp lies in a snow or desert area.
- * @param t              The ramp tile to set (un)make a snow/desert area
- * @param snow_or_desert Make (true) or unmake the tile a snow/desert area
- * @pre IsBridgeTile(t)
- */
-static inline void SetBridgeSnowOrDesert(TileIndex t, bool snow_or_desert)
-{
-	assert(IsBridgeTile(t));
-	SB(_m[t].m4, 7, 1, snow_or_desert);
-}
-
 /**
  * Finds the end of a bridge in the specified direction starting at a middle tile
  * @param t the bridge tile to find the bridge ramp for
@@ -187,7 +133,6 @@ static inline void ClearSingleBridgeMiddle(TileIndex t, Axis a)
 	ClrBit(_m[t].m6, 6 + a);
 }
 
-
 /**
  * Removes bridges from the given, that is bridges along the X and Y axis.
  * @param t the tile to remove the bridge from
diff --git a/src/elrail.cpp b/src/elrail.cpp
index ffd567f89..fd6e47fec 100644
--- a/src/elrail.cpp
+++ b/src/elrail.cpp
@@ -66,6 +66,8 @@
 #include "train.h"
 #include "gui.h"
 #include "transparency.h"
+#include "tunnelbridge_map.h"
+
 
 static inline TLG GetTLG(TileIndex t)
 {
@@ -93,14 +95,14 @@ static TrackBits GetRailTrackBitsUniversal(TileIndex t, byte *override)
 		case MP_TUNNELBRIDGE:
 			if (IsTunnel(t)) {
 				if (GetRailType(t) != RAILTYPE_ELECTRIC) return TRACK_BIT_NONE;
-				if (override != NULL) *override = 1 << GetTunnelDirection(t);
-				return AxisToTrackBits(DiagDirToAxis(GetTunnelDirection(t)));
+				if (override != NULL) *override = 1 << GetTunnelBridgeDirection(t);
+				return AxisToTrackBits(DiagDirToAxis(GetTunnelBridgeDirection(t)));
 			} else {
 				if (GetRailType(t) != RAILTYPE_ELECTRIC) return TRACK_BIT_NONE;
 				if (override != NULL && DistanceMax(t, GetOtherBridgeEnd(t)) > 1) {
-					*override = 1 << GetBridgeRampDirection(t);
+					*override = 1 << GetTunnelBridgeDirection(t);
 				}
-				return AxisToTrackBits(DiagDirToAxis(GetBridgeRampDirection(t)));
+				return AxisToTrackBits(DiagDirToAxis(GetTunnelBridgeDirection(t)));
 			}
 
 		case MP_ROAD:
@@ -131,7 +133,7 @@ static void AdjustTileh(TileIndex tile, Slope *tileh)
 		} else if (*tileh != SLOPE_FLAT) {
 			*tileh = SLOPE_FLAT;
 		} else {
-			switch (GetBridgeRampDirection(tile)) {
+			switch (GetTunnelBridgeDirection(tile)) {
 				case DIAGDIR_NE: *tileh = SLOPE_NE; break;
 				case DIAGDIR_SE: *tileh = SLOPE_SE; break;
 				case DIAGDIR_SW: *tileh = SLOPE_SW; break;
@@ -188,7 +190,7 @@ void DrawCatenaryOnTunnel(const TileInfo *ti)
 
 	if ((GetRailType(ti->tile) != RAILTYPE_ELECTRIC) || _patches.disable_elrails) return;
 
-	DiagDirection dir = GetTunnelDirection(ti->tile);
+	DiagDirection dir = GetTunnelBridgeDirection(ti->tile);
 
 	const SortableSpriteStruct *sss = &CatenarySpriteData_Tunnel[dir];
 	const int *BB_data = _tunnel_wire_BB[dir];
@@ -247,7 +249,7 @@ static void DrawCatenaryRailway(const TileInfo *ti)
 		 * existing foundataions, so we do have to do that manually later on.*/
 		tileh[TS_NEIGHBOUR] = GetTileSlope(neighbour, NULL);
 		trackconfig[TS_NEIGHBOUR] = GetRailTrackBitsUniversal(neighbour, NULL);
-		if (IsTunnelTile(neighbour) && i != GetTunnelDirection(neighbour)) trackconfig[TS_NEIGHBOUR] = TRACK_BIT_NONE;
+		if (IsTunnelTile(neighbour) && i != GetTunnelBridgeDirection(neighbour)) trackconfig[TS_NEIGHBOUR] = TRACK_BIT_NONE;
 
 		/* If the neighboured tile does not smoothly connect to the current tile (because of a foundation),
 		 * we have to draw all pillars on the current tile. */
@@ -264,7 +266,7 @@ static void DrawCatenaryRailway(const TileInfo *ti)
 			/* Next to us, we have a bridge head, don't worry about that one, if it shows away from us */
 			if (TrackSourceTile[i][k] == TS_NEIGHBOUR &&
 			    IsBridgeTile(neighbour) &&
-			    GetBridgeRampDirection(neighbour) == ReverseDiagDir(i)) {
+			    GetTunnelBridgeDirection(neighbour) == ReverseDiagDir(i)) {
 				continue;
 			}
 
@@ -291,7 +293,7 @@ static void DrawCatenaryRailway(const TileInfo *ti)
 		/* Read the foundataions if they are present, and adjust the tileh */
 		if (trackconfig[TS_NEIGHBOUR] != TRACK_BIT_NONE && IsTileType(neighbour, MP_RAILWAY) && GetRailType(neighbour) == RAILTYPE_ELECTRIC) foundation = GetRailFoundation(tileh[TS_NEIGHBOUR], trackconfig[TS_NEIGHBOUR]);
 		if (IsBridgeTile(neighbour)) {
-			foundation = GetBridgeFoundation(tileh[TS_NEIGHBOUR], DiagDirToAxis(GetBridgeRampDirection(neighbour)));
+			foundation = GetBridgeFoundation(tileh[TS_NEIGHBOUR], DiagDirToAxis(GetTunnelBridgeDirection(neighbour)));
 		}
 
 		ApplyFoundationToSlope(foundation, &tileh[TS_NEIGHBOUR]);
@@ -443,7 +445,7 @@ void DrawCatenary(const TileInfo *ti)
 	if (MayHaveBridgeAbove(ti->tile) && IsBridgeAbove(ti->tile)) {
 		TileIndex head = GetNorthernBridgeEnd(ti->tile);
 
-		if (GetBridgeTransportType(head) == TRANSPORT_RAIL && GetRailType(head) == RAILTYPE_ELECTRIC) {
+		if (GetTunnelBridgeTransportType(head) == TRANSPORT_RAIL && GetRailType(head) == RAILTYPE_ELECTRIC) {
 			DrawCatenaryOnBridge(ti);
 		}
 	}
diff --git a/src/npf.cpp b/src/npf.cpp
index 8fdc97fe8..696484e03 100644
--- a/src/npf.cpp
+++ b/src/npf.cpp
@@ -19,6 +19,7 @@
 #include "tunnel_map.h"
 #include "network/network.h"
 #include "water_map.h"
+#include "tunnelbridge_map.h"
 
 static AyStar _npf_aystar;
 
@@ -170,7 +171,7 @@ static uint NPFTunnelCost(AyStarNode* current)
 {
 	DiagDirection exitdir = TrackdirToExitdir((Trackdir)current->direction);
 	TileIndex tile = current->tile;
-	if (GetTunnelDirection(tile) == ReverseDiagDir(exitdir)) {
+	if (GetTunnelBridgeDirection(tile) == ReverseDiagDir(exitdir)) {
 		/* We just popped out if this tunnel, since were
 		 * facing the tunnel exit */
 		FindLengthOfTunnelResult flotr;
@@ -480,8 +481,8 @@ static bool VehicleMayEnterTile(Owner owner, TileIndex tile, DiagDirection enter
 			break;
 
 		case MP_TUNNELBRIDGE:
-			if ((IsTunnel(tile) && GetTunnelTransportType(tile) == TRANSPORT_RAIL) ||
-					(IsBridge(tile) && GetBridgeTransportType(tile) == TRANSPORT_RAIL)) {
+			if ((IsTunnel(tile) && GetTunnelBridgeTransportType(tile) == TRANSPORT_RAIL) ||
+					(IsBridge(tile) && GetTunnelBridgeTransportType(tile) == TRANSPORT_RAIL)) {
 				return IsTileOwner(tile, owner);
 			}
 			break;
@@ -533,13 +534,13 @@ static void NPFFollowTrack(AyStar* aystar, OpenListNode* current)
 	DEBUG(npf, 4, "Expanding: (%d, %d, %d) [%d]", TileX(src_tile), TileY(src_tile), src_trackdir, src_tile);
 
 	/* Find dest tile */
-	if (IsTunnelTile(src_tile) && GetTunnelDirection(src_tile) == src_exitdir) {
+	if (IsTunnelTile(src_tile) && GetTunnelBridgeDirection(src_tile) == src_exitdir) {
 		/* This is a tunnel. We know this tunnel is our type,
 		 * otherwise we wouldn't have got here. It is also facing us,
 		 * so we should skip it's body */
 		dst_tile = GetOtherTunnelEnd(src_tile);
 		override_dst_check = true;
-	} else if (IsBridgeTile(src_tile) && GetBridgeRampDirection(src_tile) == src_exitdir) {
+	} else if (IsBridgeTile(src_tile) && GetTunnelBridgeDirection(src_tile) == src_exitdir) {
 		dst_tile = GetOtherBridgeEnd(src_tile);
 		override_dst_check = true;
 	} else if (type != TRANSPORT_WATER && (IsStandardRoadStopTile(src_tile) || IsTileDepotType(src_tile, type))) {
@@ -592,9 +593,9 @@ static void NPFFollowTrack(AyStar* aystar, OpenListNode* current)
 	if (!override_dst_check) {
 		if (IsTileType(dst_tile, MP_TUNNELBRIDGE)) {
 			if (IsTunnel(dst_tile)) {
-				if (GetTunnelDirection(dst_tile) != src_exitdir) return;
+				if (GetTunnelBridgeDirection(dst_tile) != src_exitdir) return;
 			} else {
-				if (GetBridgeRampDirection(dst_tile) != src_exitdir) return;
+				if (GetTunnelBridgeDirection(dst_tile) != src_exitdir) return;
 			}
 		}
 	}
diff --git a/src/openttd.cpp b/src/openttd.cpp
index 7d841f0bb..46f46c594 100644
--- a/src/openttd.cpp
+++ b/src/openttd.cpp
@@ -77,6 +77,7 @@
 #include "industry_map.h"
 #include "unmovable_map.h"
 #include "tree_map.h"
+#include "tunnelbridge_map.h"
 
 #include <stdarg.h>
 
@@ -1639,7 +1640,7 @@ bool AfterLoadGame()
 				case MP_TUNNELBRIDGE:
 					/* Middle part of "old" bridges */
 					if (old_bridge && IsBridgeTile(t) && HasBit(_m[t].m5, 6)) break;
-					if ((IsTunnel(t) ? GetTunnelTransportType(t) : (old_bridge ? (TransportType)GB(_m[t].m5, 1, 2) : GetBridgeTransportType(t))) == TRANSPORT_ROAD) {
+					if ((IsTunnel(t) ? GetTunnelBridgeTransportType(t) : (old_bridge ? (TransportType)GB(_m[t].m5, 1, 2) : GetTunnelBridgeTransportType(t))) == TRANSPORT_ROAD) {
 						SetRoadTypes(t, ROADTYPES_ROAD);
 					}
 					break;
@@ -1699,7 +1700,7 @@ bool AfterLoadGame()
 		FOR_ALL_VEHICLES(v) {
 			if (v->type != VEH_TRAIN && v->type != VEH_ROAD) continue;
 			if (IsBridgeTile(v->tile)) {
-				DiagDirection dir = GetBridgeRampDirection(v->tile);
+				DiagDirection dir = GetTunnelBridgeDirection(v->tile);
 
 				if (dir != DirToDiagDir(v->direction)) continue;
 				switch (dir) {
@@ -1757,11 +1758,11 @@ bool AfterLoadGame()
 
 				case MP_TUNNELBRIDGE:
 					if (IsTunnel(t)) {
-						if (GetTunnelTransportType(t) == TRANSPORT_RAIL) {
+						if (GetTunnelBridgeTransportType(t) == TRANSPORT_RAIL) {
 							SetRailType(t, UpdateRailType(GetRailType(t), min_rail));
 						}
 					} else {
-						if (GetBridgeTransportType(t) == TRANSPORT_RAIL) {
+						if (GetTunnelBridgeTransportType(t) == TRANSPORT_RAIL) {
 							SetRailType(t, UpdateRailType(GetRailType(t), min_rail));
 						}
 					}
diff --git a/src/pathfind.cpp b/src/pathfind.cpp
index 2588c1c76..4cefc7125 100644
--- a/src/pathfind.cpp
+++ b/src/pathfind.cpp
@@ -17,6 +17,7 @@
 #include "tunnel_map.h"
 #include "variables.h"
 #include "depot.h"
+#include "tunnelbridge_map.h"
 
 /* remember which tiles we have already visited so we don't visit them again. */
 static bool TPFSetTileBit(TrackPathFinder *tpf, TileIndex tile, int dir)
@@ -210,7 +211,7 @@ FindLengthOfTunnelResult FindLengthOfTunnel(TileIndex tile, DiagDirection dir)
 		tile += delta;
 	} while(
 		!IsTunnelTile(tile) ||
-		GetTunnelDirection(tile) != dir ||
+		GetTunnelBridgeDirection(tile) != dir ||
 		GetTileZ(tile) != z
 	);
 
@@ -260,13 +261,13 @@ static inline void TPFMode1_NormalCase(TrackPathFinder* tpf, TileIndex tile, Til
 	 * and transport type match */
 	if (IsTileType(tile, MP_TUNNELBRIDGE)) {
 		if (IsTunnel(tile)) {
-			if (GetTunnelDirection(tile) != direction ||
-					GetTunnelTransportType(tile) != tpf->tracktype) {
+			if (GetTunnelBridgeDirection(tile) != direction ||
+					GetTunnelBridgeTransportType(tile) != tpf->tracktype) {
 				return;
 			}
 		} else if (IsBridge(tile)) {
-			if (GetBridgeRampDirection(tile) != direction ||
-					GetBridgeTransportType(tile) != tpf->tracktype) {
+			if (GetTunnelBridgeDirection(tile) != direction ||
+					GetTunnelBridgeTransportType(tile) != tpf->tracktype) {
 				return;
 			}
 		}
@@ -307,23 +308,23 @@ static void TPFMode1(TrackPathFinder* tpf, TileIndex tile, DiagDirection directi
 
 	if (IsTileType(tile, MP_TUNNELBRIDGE)) {
 		if (IsTunnel(tile)) {
-			if (GetTunnelTransportType(tile) != tpf->tracktype) {
+			if (GetTunnelBridgeTransportType(tile) != tpf->tracktype) {
 				return;
 			}
 			/* Only skip through the tunnel if heading inwards. We can
 			 * be headed outwards if our starting position was in a
 			 * tunnel and we're pathfinding backwards */
-			if (GetTunnelDirection(tile) == direction) {
+			if (GetTunnelBridgeDirection(tile) == direction) {
 				tile = SkipToEndOfTunnel(tpf, tile, direction);
-			} else if (GetTunnelDirection(tile) != ReverseDiagDir(direction)) {
+			} else if (GetTunnelBridgeDirection(tile) != ReverseDiagDir(direction)) {
 				/* We don't support moving through the sides of a tunnel
 				 * entrance :-) */
 				return;
 			}
 		} else {
 			TileIndex tile_end;
-			if (GetBridgeRampDirection(tile) != direction ||
-					GetBridgeTransportType(tile) != tpf->tracktype) {
+			if (GetTunnelBridgeDirection(tile) != direction ||
+					GetTunnelBridgeTransportType(tile) != tpf->tracktype) {
 				return;
 			}
 			//fprintf(stderr, "%s: Planning over bridge\n", __func__);
@@ -722,12 +723,12 @@ start_at:
 		 *   need to find the exit of the tunnel. */
 		if (IsTileType(tile, MP_TUNNELBRIDGE)) {
 			if (IsTunnel(tile)) {
-				if (GetTunnelDirection(tile) != ReverseDiagDir(direction)) {
+				if (GetTunnelBridgeDirection(tile) != ReverseDiagDir(direction)) {
 					FindLengthOfTunnelResult flotr;
 
 					/* We are not just driving out of the tunnel */
-					if (GetTunnelDirection(tile) != direction ||
-							GetTunnelTransportType(tile) != tpf->tracktype) {
+					if (GetTunnelBridgeDirection(tile) != direction ||
+							GetTunnelBridgeTransportType(tile) != tpf->tracktype) {
 						/* We are not driving into the tunnel, or it is an invalid tunnel */
 						continue;
 					}
@@ -742,10 +743,10 @@ start_at:
 				}
 			} else {
 				TileIndex tile_end;
-				if (GetBridgeRampDirection(tile) != ReverseDiagDir(direction)) {
+				if (GetTunnelBridgeDirection(tile) != ReverseDiagDir(direction)) {
 					/* We are not just leaving the bridge */
-					if (GetBridgeRampDirection(tile) != direction ||
-							GetBridgeTransportType(tile) != tpf->tracktype) {
+					if (GetTunnelBridgeDirection(tile) != direction ||
+							GetTunnelBridgeTransportType(tile) != tpf->tracktype) {
 						/* Not entering the bridge or not compatible */
 						continue;
 					}
diff --git a/src/rail.cpp b/src/rail.cpp
index 8bf83a36a..f3f62175f 100644
--- a/src/rail.cpp
+++ b/src/rail.cpp
@@ -8,6 +8,8 @@
 #include "rail.h"
 #include "station_map.h"
 #include "tunnel_map.h"
+#include "tunnelbridge_map.h"
+
 
 /* XXX: Below 3 tables store duplicate data. Maybe remove some? */
 /* Maps a trackdir to the bit that stores its status in the map arrays, in the
@@ -131,9 +133,9 @@ RailType GetTileRailType(TileIndex tile)
 
 		case MP_TUNNELBRIDGE:
 			if (IsTunnel(tile)) {
-				if (GetTunnelTransportType(tile) == TRANSPORT_RAIL) return GetRailType(tile);
+				if (GetTunnelBridgeTransportType(tile) == TRANSPORT_RAIL) return GetRailType(tile);
 			} else {
-				if (GetBridgeTransportType(tile) == TRANSPORT_RAIL) return GetRailType(tile);
+				if (GetTunnelBridgeTransportType(tile) == TRANSPORT_RAIL) return GetRailType(tile);
 			}
 			break;
 
diff --git a/src/rail_cmd.cpp b/src/rail_cmd.cpp
index b29f63538..793d9363f 100644
--- a/src/rail_cmd.cpp
+++ b/src/rail_cmd.cpp
@@ -42,6 +42,8 @@
 #include "autoslope.h"
 #include "transparency.h"
 #include "water.h"
+#include "tunnelbridge_map.h"
+
 
 const byte _track_sloped_sprites[14] = {
 	14, 15, 22, 13,
@@ -927,12 +929,12 @@ static bool CheckSignalAutoFill(TileIndex &tile, Trackdir &trackdir, int &signal
 			TileIndex orig_tile = tile;
 			/* Skip to end of tunnel or bridge */
 			if (IsBridge(tile)) {
-				if (GetBridgeTransportType(tile) != TRANSPORT_RAIL) return false;
-				if (GetBridgeRampDirection(tile) != TrackdirToExitdir(trackdir)) return false;
+				if (GetTunnelBridgeTransportType(tile) != TRANSPORT_RAIL) return false;
+				if (GetTunnelBridgeDirection(tile) != TrackdirToExitdir(trackdir)) return false;
 				tile = GetOtherBridgeEnd(tile);
 			} else {
-				if (GetTunnelTransportType(tile) != TRANSPORT_RAIL) return false;
-				if (GetTunnelDirection(tile) != TrackdirToExitdir(trackdir)) return false;
+				if (GetTunnelBridgeTransportType(tile) != TRANSPORT_RAIL) return false;
+				if (GetTunnelBridgeDirection(tile) != TrackdirToExitdir(trackdir)) return false;
 				tile = GetOtherTunnelEnd(tile);
 			}
 			signal_ctr += 2 + DistanceMax(orig_tile, tile) * 2;
diff --git a/src/rail_gui.cpp b/src/rail_gui.cpp
index af2a8f25e..6b80ab81b 100644
--- a/src/rail_gui.cpp
+++ b/src/rail_gui.cpp
@@ -32,6 +32,8 @@
 #include "road_map.h"
 #include "station_map.h"
 #include "tunnel_map.h"
+#include "tunnelbridge_map.h"
+
 
 static RailType _cur_railtype;
 static bool _remove_button_clicked;
@@ -1523,8 +1525,8 @@ void SetDefaultRailGui()
 				if (IsTileType(t, MP_RAILWAY) ||
 						IsLevelCrossingTile(t) ||
 						IsRailwayStationTile(t) ||
-						(IsTunnelTile(t) && GetTunnelTransportType(t) == TRANSPORT_RAIL) ||
-						(IsBridgeTile(t) && GetBridgeTransportType(t) == TRANSPORT_RAIL)
+						(IsTunnelTile(t) && GetTunnelBridgeTransportType(t) == TRANSPORT_RAIL) ||
+						(IsBridgeTile(t) && GetTunnelBridgeTransportType(t) == TRANSPORT_RAIL)
 						) {
 					count[GetRailType(t)]++;
 				}
diff --git a/src/road_cmd.cpp b/src/road_cmd.cpp
index b3b38e02c..df4404a05 100644
--- a/src/road_cmd.cpp
+++ b/src/road_cmd.cpp
@@ -34,6 +34,8 @@
 #include "misc/autoptr.hpp"
 #include "autoslope.h"
 #include "transparency.h"
+#include "tunnelbridge_map.h"
+
 
 #define M(x) (1 << (x))
 /* Level crossings may only be built on these slopes */
@@ -133,10 +135,10 @@ CommandCost CmdRemoveRoad(TileIndex tile, uint32 flags, uint32 p1, uint32 p2)
 			{
 				TileIndex endtile;
 				if (IsTunnel(tile)) {
-					if (GetTunnelTransportType(tile) != TRANSPORT_ROAD) return CMD_ERROR;
+					if (GetTunnelBridgeTransportType(tile) != TRANSPORT_ROAD) return CMD_ERROR;
 					endtile = GetOtherTunnelEnd(tile);
 				} else {
-					if (GetBridgeTransportType(tile) != TRANSPORT_ROAD) return CMD_ERROR;
+					if (GetTunnelBridgeTransportType(tile) != TRANSPORT_ROAD) return CMD_ERROR;
 					endtile = GetOtherBridgeEnd(tile);
 				}
 
@@ -175,7 +177,7 @@ CommandCost CmdRemoveRoad(TileIndex tile, uint32 flags, uint32 p1, uint32 p2)
 				MarkTileDirtyByTile(tile);
 				MarkTileDirtyByTile(other_end);
 				if (IsBridge(tile)) {
-					TileIndexDiff delta = TileOffsByDiagDir(GetBridgeRampDirection(tile));
+					TileIndexDiff delta = TileOffsByDiagDir(GetTunnelBridgeDirection(tile));
 
 					for (TileIndex t = tile + delta; t != other_end; t += delta) MarkTileDirtyByTile(t);
 				}
@@ -514,10 +516,10 @@ CommandCost CmdBuildRoad(TileIndex tile, uint32 flags, uint32 p1, uint32 p2)
 			{
 				TileIndex endtile;
 				if (IsTunnel(tile)) {
-					if (GetTunnelTransportType(tile) != TRANSPORT_ROAD) return CMD_ERROR;
+					if (GetTunnelBridgeTransportType(tile) != TRANSPORT_ROAD) return CMD_ERROR;
 					endtile = GetOtherTunnelEnd(tile);
 				} else {
-					if (GetBridgeTransportType(tile) != TRANSPORT_ROAD) return CMD_ERROR;
+					if (GetTunnelBridgeTransportType(tile) != TRANSPORT_ROAD) return CMD_ERROR;
 					endtile = GetOtherBridgeEnd(tile);
 				}
 				if (HasBit(GetRoadTypes(tile), rt)) return_cmd_error(STR_1007_ALREADY_BUILT);
@@ -576,7 +578,7 @@ do_clear:;
 				MarkTileDirtyByTile(other_end);
 				MarkTileDirtyByTile(tile);
 				if (IsBridge(tile)) {
-					TileIndexDiff delta = TileOffsByDiagDir(GetBridgeRampDirection(tile));
+					TileIndexDiff delta = TileOffsByDiagDir(GetTunnelBridgeDirection(tile));
 
 					for (TileIndex t = tile + delta; t != other_end; t += delta) MarkTileDirtyByTile(t);
 				}
@@ -691,12 +693,12 @@ CommandCost CmdBuildLongRoad(TileIndex end_tile, uint32 flags, uint32 p1, uint32
 			/* Only pay for the upgrade on one side of the bridges and tunnels */
 			if (IsTileType(tile, MP_TUNNELBRIDGE)) {
 				if (IsBridge(tile)) {
-					if ((!had_bridge || GetBridgeRampDirection(tile) == DIAGDIR_SE || GetBridgeRampDirection(tile) == DIAGDIR_SW)) {
+					if ((!had_bridge || GetTunnelBridgeDirection(tile) == DIAGDIR_SE || GetTunnelBridgeDirection(tile) == DIAGDIR_SW)) {
 						cost.AddCost(ret);
 					}
 					had_bridge = true;
 				} else {
-					if ((!had_tunnel || GetTunnelDirection(tile) == DIAGDIR_SE || GetTunnelDirection(tile) == DIAGDIR_SW)) {
+					if ((!had_tunnel || GetTunnelBridgeDirection(tile) == DIAGDIR_SE || GetTunnelBridgeDirection(tile) == DIAGDIR_SW)) {
 						cost.AddCost(ret);
 					}
 					had_tunnel = true;
diff --git a/src/road_map.cpp b/src/road_map.cpp
index 7dc26f079..0bdf66dfe 100644
--- a/src/road_map.cpp
+++ b/src/road_map.cpp
@@ -12,6 +12,7 @@
 #include "tunnel_map.h"
 #include "station_map.h"
 #include "depot.h"
+#include "tunnelbridge_map.h"
 
 
 RoadBits GetAnyRoadBits(TileIndex tile, RoadType rt)
@@ -34,11 +35,11 @@ RoadBits GetAnyRoadBits(TileIndex tile, RoadType rt)
 
 		case MP_TUNNELBRIDGE:
 			if (IsTunnel(tile)) {
-				if (GetTunnelTransportType(tile) != TRANSPORT_ROAD) return ROAD_NONE;
-				return DiagDirToRoadBits(ReverseDiagDir(GetTunnelDirection(tile)));
+				if (GetTunnelBridgeTransportType(tile) != TRANSPORT_ROAD) return ROAD_NONE;
+				return DiagDirToRoadBits(ReverseDiagDir(GetTunnelBridgeDirection(tile)));
 			} else {
-				if (GetBridgeTransportType(tile) != TRANSPORT_ROAD) return ROAD_NONE;
-				return DiagDirToRoadBits(ReverseDiagDir(GetBridgeRampDirection(tile)));
+				if (GetTunnelBridgeTransportType(tile) != TRANSPORT_ROAD) return ROAD_NONE;
+				return DiagDirToRoadBits(ReverseDiagDir(GetTunnelBridgeDirection(tile)));
 			}
 
 		default: return ROAD_NONE;
diff --git a/src/roadveh_cmd.cpp b/src/roadveh_cmd.cpp
index 7ce4a9c7a..2850b2d7c 100644
--- a/src/roadveh_cmd.cpp
+++ b/src/roadveh_cmd.cpp
@@ -37,6 +37,8 @@
 #include "yapf/yapf.h"
 #include "date.h"
 #include "cargotype.h"
+#include "tunnelbridge_map.h"
+
 
 static const uint16 _roadveh_images[63] = {
 	0xCD4, 0xCDC, 0xCE4, 0xCEC, 0xCF4, 0xCFC, 0xD0C, 0xD14,
@@ -549,8 +551,8 @@ CommandCost CmdTurnRoadVeh(TileIndex tile, uint32 flags, uint32 p1, uint32 p2)
 
 	if (IsTileType(v->tile, MP_ROAD) && GetRoadTileType(v->tile) == ROAD_TILE_NORMAL && GetDisallowedRoadDirections(v->tile) != DRD_NONE) return CMD_ERROR;
 
-	if (IsTunnelTile(v->tile) && DirToDiagDir(v->direction) == GetTunnelDirection(v->tile)) return CMD_ERROR;
-	if (IsBridgeTile(v->tile) && DirToDiagDir(v->direction) == GetBridgeRampDirection(v->tile)) return CMD_ERROR;
+	if (IsTunnelTile(v->tile) && DirToDiagDir(v->direction) == GetTunnelBridgeDirection(v->tile)) return CMD_ERROR;
+	if (IsBridgeTile(v->tile) && DirToDiagDir(v->direction) == GetTunnelBridgeDirection(v->tile)) return CMD_ERROR;
 
 	if (flags & DC_EXEC) v->u.road.reverse_ctr = 180;
 
@@ -1406,9 +1408,9 @@ static Trackdir FollowPreviousRoadVehicle(const Vehicle *v, const Vehicle *prev,
 		DiagDirection diag_dir = INVALID_DIAGDIR;
 
 		if (IsTunnelTile(tile)) {
-			diag_dir = GetTunnelDirection(tile);
+			diag_dir = GetTunnelBridgeDirection(tile);
 		} else if (IsBridgeTile(tile)) {
-			diag_dir = GetBridgeRampDirection(tile);
+			diag_dir = GetTunnelBridgeDirection(tile);
 		} else if (IsTileType(tile, MP_ROAD) && GetRoadTileType(tile) == ROAD_TILE_DEPOT) {
 			diag_dir = ReverseDiagDir(GetRoadDepotDirection(tile));
 		}
diff --git a/src/smallmap_gui.cpp b/src/smallmap_gui.cpp
index bb2ee28bb..638a43322 100644
--- a/src/smallmap_gui.cpp
+++ b/src/smallmap_gui.cpp
@@ -28,6 +28,8 @@
 #include "sound.h"
 #include "variables.h"
 #include "blitter/factory.hpp"
+#include "tunnelbridge_map.h"
+
 
 static const Widget _smallmap_widgets[] = {
 {  WWT_CLOSEBOX,   RESIZE_NONE,    13,     0,    10,     0,    13, STR_00C5,                STR_018B_CLOSE_WINDOW},
@@ -340,9 +342,9 @@ static inline TileType GetEffectiveTileType(TileIndex tile)
 		TransportType tt;
 
 		if (IsTunnel(tile)) {
-			tt = GetTunnelTransportType(tile);
+			tt = GetTunnelBridgeTransportType(tile);
 		} else {
-			tt = GetBridgeTransportType(tile);
+			tt = GetTunnelBridgeTransportType(tile);
 		}
 		switch (tt) {
 			case TRANSPORT_RAIL: t = MP_RAILWAY; break;
diff --git a/src/town_cmd.cpp b/src/town_cmd.cpp
index 6dcac49d4..302146081 100644
--- a/src/town_cmd.cpp
+++ b/src/town_cmd.cpp
@@ -44,6 +44,8 @@
 #include "autoslope.h"
 #include "waypoint.h"
 #include "transparency.h"
+#include "tunnelbridge_map.h"
+
 
 /* Initialize the town-pool */
 DEFINE_OLD_POOL_GENERIC(Town, Town)
@@ -1062,9 +1064,9 @@ static void GrowTownInTile(TileIndex *tile_ptr, RoadBits cur_rb, DiagDirection t
 
 		/* Reached a tunnel/bridge? Then continue at the other side of it. */
 		if (IsTileType(tile, MP_TUNNELBRIDGE)) {
-			if (IsTunnel(tile) && GetTunnelTransportType(tile) == TRANSPORT_ROAD) {
+			if (IsTunnel(tile) && GetTunnelBridgeTransportType(tile) == TRANSPORT_ROAD) {
 				*tile_ptr = GetOtherTunnelEnd(tile);
-			} else if (IsBridge(tile) && GetBridgeTransportType(tile) == TRANSPORT_ROAD) {
+			} else if (IsBridge(tile) && GetTunnelBridgeTransportType(tile) == TRANSPORT_ROAD) {
 				*tile_ptr = GetOtherBridgeEnd(tile);
 			}
 			return;
diff --git a/src/train_cmd.cpp b/src/train_cmd.cpp
index 8264b0fa3..a3f551ec7 100644
--- a/src/train_cmd.cpp
+++ b/src/train_cmd.cpp
@@ -42,6 +42,8 @@
 #include "cargotype.h"
 #include "group.h"
 #include "table/sprites.h"
+#include "tunnelbridge_map.h"
+
 
 static bool TrainCheckIfLineEnds(Vehicle *v);
 static void TrainController(Vehicle *v, bool update_image);
@@ -3057,7 +3059,7 @@ static void DeleteLastWagon(Vehicle *v)
 
 		if (GetVehicleTunnelBridge(v->tile, endtile) != NULL) return; // tunnel / bridge is busy
 
-		DiagDirection dir = IsTunnel(v->tile) ? GetTunnelDirection(v->tile) : GetBridgeRampDirection(v->tile);
+		DiagDirection dir = IsTunnel(v->tile) ? GetTunnelBridgeDirection(v->tile) : GetTunnelBridgeDirection(v->tile);
 
 		/* v->direction is "random", so it cannot be used to determine the direction of the track */
 		UpdateSignalsOnSegment(v->tile, dir);
@@ -3174,7 +3176,7 @@ static bool TrainCheckIfLineEnds(Vehicle *v)
 	TileIndex tile = v->tile;
 
 	if (IsTileType(tile, MP_TUNNELBRIDGE)) {
-		DiagDirection dir = IsTunnel(tile) ? GetTunnelDirection(tile) : GetBridgeRampDirection(tile);
+		DiagDirection dir = IsTunnel(tile) ? GetTunnelBridgeDirection(tile) : GetTunnelBridgeDirection(tile);
 		if (DiagDirToDir(dir) == v->direction) return true;
 	}
 
diff --git a/src/tunnel_map.cpp b/src/tunnel_map.cpp
index 593d3fe6b..ac7255155 100644
--- a/src/tunnel_map.cpp
+++ b/src/tunnel_map.cpp
@@ -6,6 +6,8 @@
 #include "openttd.h"
 #include "tile.h"
 #include "tunnel_map.h"
+#include "tunnelbridge_map.h"
+
 
 /**
  * Gets the other end of the tunnel. Where a vehicle would reappear when it
@@ -15,7 +17,7 @@
  */
 TileIndex GetOtherTunnelEnd(TileIndex tile)
 {
-	DiagDirection dir = GetTunnelDirection(tile);
+	DiagDirection dir = GetTunnelBridgeDirection(tile);
 	TileIndexDiff delta = TileOffsByDiagDir(dir);
 	uint z = GetTileZ(tile);
 
@@ -24,7 +26,7 @@ TileIndex GetOtherTunnelEnd(TileIndex tile)
 		tile += delta;
 	} while (
 		!IsTunnelTile(tile) ||
-		GetTunnelDirection(tile) != dir ||
+		GetTunnelBridgeDirection(tile) != dir ||
 		GetTileZ(tile) != z
 	);
 
@@ -52,7 +54,7 @@ bool IsTunnelInWayDir(TileIndex tile, uint z, DiagDirection dir)
 	return
 		z == height &&
 		IsTunnelTile(tile) &&
-		GetTunnelDirection(tile) == dir;
+		GetTunnelBridgeDirection(tile) == dir;
 }
 
 /**
diff --git a/src/tunnel_map.h b/src/tunnel_map.h
index e4092cf15..921137a6e 100644
--- a/src/tunnel_map.h
+++ b/src/tunnel_map.h
@@ -11,6 +11,7 @@
 #include "rail.h"
 #include "road.h"
 
+
 /**
  * Is this a tunnel (entrance)?
  * @param t the tile that might be a tunnel
@@ -23,7 +24,6 @@ static inline bool IsTunnel(TileIndex t)
 	return !HasBit(_m[t].m5, 7);
 }
 
-
 /**
  * Is this a tunnel (entrance)?
  * @param t the tile that might be a tunnel
@@ -34,62 +34,10 @@ static inline bool IsTunnelTile(TileIndex t)
 	return IsTileType(t, MP_TUNNELBRIDGE) && IsTunnel(t);
 }
 
-/**
- * Gets the direction facing out of the tunnel
- * @param t the tile to get the tunnel facing direction of
- * @pre IsTunnelTile(t)
- * @return the direction the tunnel is facing
- */
-static inline DiagDirection GetTunnelDirection(TileIndex t)
-{
-	assert(IsTunnelTile(t));
-	return (DiagDirection)GB(_m[t].m5, 0, 2);
-}
-
-/**
- * Gets the transport type of the tunnel (road or rail)
- * @param t the tunnel entrance tile to get the type of
- * @pre IsTunnelTile(t)
- * @return the transport type in the tunnel
- */
-static inline TransportType GetTunnelTransportType(TileIndex t)
-{
-	assert(IsTunnelTile(t));
-	return (TransportType)GB(_m[t].m5, 2, 2);
-}
-
-/**
- * Is this tunnel entrance in a snowy or desert area?
- * @param t the tunnel entrance tile
- * @pre IsTunnelTile(t)
- * @return true if and only if the tunnel entrance is in a snowy/desert area
- */
-static inline bool HasTunnelSnowOrDesert(TileIndex t)
-{
-	assert(IsTunnelTile(t));
-	return HasBit(_m[t].m4, 7);
-}
-
-/**
- * Places this tunnel entrance in a snowy or desert area,
- * or takes it out of there.
- * @param t the tunnel entrance tile
- * @param snow_or_desert is the entrance in snow or desert (true), when
- *                       not in snow and not in desert false
- * @pre IsTunnelTile(t)
- */
-static inline void SetTunnelSnowOrDesert(TileIndex t, bool snow_or_desert)
-{
-	assert(IsTunnelTile(t));
-	SB(_m[t].m4, 7, 1, snow_or_desert);
-}
-
-
 TileIndex GetOtherTunnelEnd(TileIndex);
 bool IsTunnelInWay(TileIndex, uint z);
 bool IsTunnelInWayDir(TileIndex tile, uint z, DiagDirection dir);
 
-
 /**
  * Makes a road tunnel entrance
  * @param t the entrance of the tunnel
diff --git a/src/tunnelbridge_cmd.cpp b/src/tunnelbridge_cmd.cpp
index 272d1bca6..14304e624 100644
--- a/src/tunnelbridge_cmd.cpp
+++ b/src/tunnelbridge_cmd.cpp
@@ -34,9 +34,10 @@
 #include "newgrf_sound.h"
 #include "autoslope.h"
 #include "transparency.h"
-
+#include "tunnelbridge_map.h"
 #include "table/bridge_land.h"
 
+
 const Bridge orig_bridge[] = {
 /*
 	     year of availablity
@@ -266,7 +267,7 @@ CommandCost CmdBuildBridge(TileIndex end_tile, uint32 flags, uint32 p1, uint32 p
 
 	if (IsBridgeTile(tile_start) && IsBridgeTile(tile_end) &&
 			GetOtherBridgeEnd(tile_start) == tile_end &&
-			GetBridgeTransportType(tile_start) == transport_type) {
+			GetTunnelBridgeTransportType(tile_start) == transport_type) {
 		/* Replace a current bridge. */
 
 		/* If this is a railway bridge, make sure the railtypes match. */
@@ -391,7 +392,7 @@ CommandCost CmdBuildBridge(TileIndex end_tile, uint32 flags, uint32 p1, uint32 p
 			case MP_TUNNELBRIDGE:
 				if (IsTunnel(tile)) break;
 				if (replace_bridge) break;
-				if (direction == DiagDirToAxis(GetBridgeRampDirection(tile))) goto not_valid_below;
+				if (direction == DiagDirToAxis(GetTunnelBridgeDirection(tile))) goto not_valid_below;
 				if (z_start < GetBridgeHeight(tile)) goto not_valid_below;
 				break;
 
@@ -602,7 +603,7 @@ static CommandCost DoClearTunnel(TileIndex tile, uint32 flags)
 	if (flags & DC_EXEC) {
 		/* We first need to request the direction before calling DoClearSquare
 		 *  else the direction is always 0.. dah!! ;) */
-		DiagDirection dir = GetTunnelDirection(tile);
+		DiagDirection dir = GetTunnelBridgeDirection(tile);
 		Track track;
 
 		/* Adjust the town's player rating. Do this before removing the tile owner info. */
@@ -636,7 +637,7 @@ static CommandCost DoClearBridge(TileIndex tile, uint32 flags)
 
 	if (GetVehicleTunnelBridge(tile, endtile) != NULL) return CMD_ERROR;
 
-	direction = GetBridgeRampDirection(tile);
+	direction = GetTunnelBridgeDirection(tile);
 	delta = TileOffsByDiagDir(direction);
 
 	if (IsTileOwner(tile, OWNER_TOWN) && _game_mode != GM_EDITOR) {
@@ -701,7 +702,7 @@ static CommandCost ClearTile_TunnelBridge(TileIndex tile, byte flags)
  */
 CommandCost DoConvertTunnelBridgeRail(TileIndex tile, RailType totype, bool exec)
 {
-	if (IsTunnel(tile) && GetTunnelTransportType(tile) == TRANSPORT_RAIL) {
+	if (IsTunnel(tile) && GetTunnelBridgeTransportType(tile) == TRANSPORT_RAIL) {
 		TileIndex endtile = GetOtherTunnelEnd(tile);
 
 		/* If not coverting rail <-> el. rail, any vehicle cannot be in tunnel */
@@ -716,7 +717,7 @@ CommandCost DoConvertTunnelBridgeRail(TileIndex tile, RailType totype, bool exec
 			MarkTileDirtyByTile(tile);
 			MarkTileDirtyByTile(endtile);
 
-			Track track = AxisToTrack(DiagDirToAxis(GetTunnelDirection(tile)));
+			Track track = AxisToTrack(DiagDirToAxis(GetTunnelBridgeDirection(tile)));
 
 			YapfNotifyTrackLayoutChange(tile, track);
 			YapfNotifyTrackLayoutChange(endtile, track);
@@ -726,7 +727,7 @@ CommandCost DoConvertTunnelBridgeRail(TileIndex tile, RailType totype, bool exec
 		}
 
 		return CommandCost((DistanceManhattan(tile, endtile) + 1) * RailConvertCost(GetRailType(tile), totype));
-	} else if (IsBridge(tile) && GetBridgeTransportType(tile) == TRANSPORT_RAIL) {
+	} else if (IsBridge(tile) && GetTunnelBridgeTransportType(tile) == TRANSPORT_RAIL) {
 		TileIndex endtile = GetOtherBridgeEnd(tile);
 
 		if (!IsCompatibleRail(GetRailType(tile), totype) &&
@@ -740,8 +741,8 @@ CommandCost DoConvertTunnelBridgeRail(TileIndex tile, RailType totype, bool exec
 			MarkTileDirtyByTile(tile);
 			MarkTileDirtyByTile(endtile);
 
-			Track track = AxisToTrack(DiagDirToAxis(GetBridgeRampDirection(tile)));
-			TileIndexDiff delta = TileOffsByDiagDir(GetBridgeRampDirection(tile));
+			Track track = AxisToTrack(DiagDirToAxis(GetTunnelBridgeDirection(tile)));
+			TileIndexDiff delta = TileOffsByDiagDir(GetTunnelBridgeDirection(tile));
 
 			YapfNotifyTrackLayoutChange(tile, track);
 			YapfNotifyTrackLayoutChange(endtile, track);
@@ -894,22 +895,22 @@ static void DrawTile_TunnelBridge(TileInfo *ti)
 			{  1,  0, -15, -14,  0, 15, 16,  1, 0, 1, 16, 15 }, // SW
 			{  0,  1, -14, -15, 15,  0,  1, 16, 1, 0, 15, 16 }, // NW
 		};
-		const int *BB_data = _tunnel_BB[GetTunnelDirection(ti->tile)];
+		const int *BB_data = _tunnel_BB[GetTunnelBridgeDirection(ti->tile)];
 
 		bool catenary = false;
 
-		if (GetTunnelTransportType(ti->tile) == TRANSPORT_RAIL) {
+		if (GetTunnelBridgeTransportType(ti->tile) == TRANSPORT_RAIL) {
 			image = GetRailTypeInfo(GetRailType(ti->tile))->base_sprites.tunnel;
 		} else {
 			image = SPR_TUNNEL_ENTRY_REAR_ROAD;
 		}
 
-		if (HasTunnelSnowOrDesert(ti->tile)) image += 32;
+		if (HasTunnelBridgeSnowOrDesert(ti->tile)) image += 32;
 
-		image += GetTunnelDirection(ti->tile) * 2;
+		image += GetTunnelBridgeDirection(ti->tile) * 2;
 		DrawGroundSprite(image, PAL_NONE);
-		if (GetTunnelTransportType(ti->tile) == TRANSPORT_ROAD) {
-			DiagDirection dir = GetTunnelDirection(ti->tile);
+		if (GetTunnelBridgeTransportType(ti->tile) == TRANSPORT_ROAD) {
+			DiagDirection dir = GetTunnelBridgeDirection(ti->tile);
 			RoadTypes rts = GetRoadTypes(ti->tile);
 
 			if (HasBit(rts, ROADTYPE_TRAM)) {
@@ -941,9 +942,9 @@ static void DrawTile_TunnelBridge(TileInfo *ti)
 	} else if (IsBridge(ti->tile)) { // XXX is this necessary?
 		const PalSpriteID *psid;
 		int base_offset;
-		bool ice = HasBridgeSnowOrDesert(ti->tile);
+		bool ice = HasTunnelBridgeSnowOrDesert(ti->tile);
 
-		if (GetBridgeTransportType(ti->tile) == TRANSPORT_RAIL) {
+		if (GetTunnelBridgeTransportType(ti->tile) == TRANSPORT_RAIL) {
 			base_offset = GetRailTypeInfo(GetRailType(ti->tile))->bridge_offset;
 			assert(base_offset != 8); // This one is used for roads
 		} else {
@@ -953,10 +954,10 @@ static void DrawTile_TunnelBridge(TileInfo *ti)
 		/* as the lower 3 bits are used for other stuff, make sure they are clear */
 		assert( (base_offset & 0x07) == 0x00);
 
-		DrawFoundation(ti, GetBridgeFoundation(ti->tileh, DiagDirToAxis(GetBridgeRampDirection(ti->tile))));
+		DrawFoundation(ti, GetBridgeFoundation(ti->tileh, DiagDirToAxis(GetTunnelBridgeDirection(ti->tile))));
 
 		/* HACK Wizardry to convert the bridge ramp direction into a sprite offset */
-		base_offset += (6 - GetBridgeRampDirection(ti->tile)) % 4;
+		base_offset += (6 - GetTunnelBridgeDirection(ti->tile)) % 4;
 
 		if (ti->tileh == SLOPE_FLAT) base_offset += 4; // sloped bridge head
 
@@ -972,7 +973,7 @@ static void DrawTile_TunnelBridge(TileInfo *ti)
 		/* draw ramp */
 
 		/* Draw Trambits as SpriteCombine */
-		if (GetBridgeTransportType(ti->tile) == TRANSPORT_ROAD) StartSpriteCombine();
+		if (GetTunnelBridgeTransportType(ti->tile) == TRANSPORT_ROAD) StartSpriteCombine();
 
 		/* HACK set the height of the BB of a sloped ramp to 1 so a vehicle on
 		 * it doesn't disappear behind it
@@ -981,11 +982,11 @@ static void DrawTile_TunnelBridge(TileInfo *ti)
 			psid->sprite, psid->pal, ti->x, ti->y, 16, 16, ti->tileh == SLOPE_FLAT ? 0 : 8, ti->z, IsTransparencySet(TO_BRIDGES)
 		);
 
-		if (GetBridgeTransportType(ti->tile) == TRANSPORT_ROAD) {
+		if (GetTunnelBridgeTransportType(ti->tile) == TRANSPORT_ROAD) {
 			RoadTypes rts = GetRoadTypes(ti->tile);
 
 			if (HasBit(rts, ROADTYPE_TRAM)) {
-				uint offset = GetBridgeRampDirection(ti->tile);
+				uint offset = GetTunnelBridgeDirection(ti->tile);
 				uint z = ti->z;
 				if (ti->tileh != SLOPE_FLAT) {
 					offset = (offset + 1) & 1;
@@ -1084,7 +1085,7 @@ void DrawBridgeMiddle(const TileInfo* ti)
 	);
 	type = GetBridgeType(rampsouth);
 
-	if (GetBridgeTransportType(rampsouth) == TRANSPORT_RAIL) {
+	if (GetTunnelBridgeTransportType(rampsouth) == TRANSPORT_RAIL) {
 		base_offset = GetRailTypeInfo(GetRailType(rampsouth))->bridge_offset;
 	} else {
 		base_offset = 8;
@@ -1102,7 +1103,7 @@ void DrawBridgeMiddle(const TileInfo* ti)
 	AddSortableSpriteToDraw(SPR_EMPTY_BOUNDING_BOX, PAL_NONE, x, y, 16, 16, 1, bridge_z - TILE_HEIGHT + BB_Z_SEPARATOR);
 
 	/* Draw Trambits as SpriteCombine */
-	if (GetBridgeTransportType(rampsouth) == TRANSPORT_ROAD) StartSpriteCombine();
+	if (GetTunnelBridgeTransportType(rampsouth) == TRANSPORT_ROAD) StartSpriteCombine();
 
 	/* Draw floor and far part of bridge*/
 	if (axis == AXIS_X) {
@@ -1113,7 +1114,7 @@ void DrawBridgeMiddle(const TileInfo* ti)
 
 	psid++;
 
-	if (GetBridgeTransportType(rampsouth) == TRANSPORT_ROAD) {
+	if (GetTunnelBridgeTransportType(rampsouth) == TRANSPORT_ROAD) {
 		RoadTypes rts = GetRoadTypes(rampsouth);
 
 		if (HasBit(rts, ROADTYPE_TRAM)) {
@@ -1137,7 +1138,7 @@ void DrawBridgeMiddle(const TileInfo* ti)
 	}
 
 	/* Draw TramFront as SpriteCombine */
-	if (GetBridgeTransportType(rampsouth) == TRANSPORT_ROAD) EndSpriteCombine();
+	if (GetTunnelBridgeTransportType(rampsouth) == TRANSPORT_ROAD) EndSpriteCombine();
 
 	psid++;
 	if (ti->z + 5 == z) {
@@ -1168,12 +1169,12 @@ static uint GetSlopeZ_TunnelBridge(TileIndex tile, uint x, uint y)
 	y &= 0xF;
 
 	if (IsTunnel(tile)) {
-		uint pos = (DiagDirToAxis(GetTunnelDirection(tile)) == AXIS_X ? y : x);
+		uint pos = (DiagDirToAxis(GetTunnelBridgeDirection(tile)) == AXIS_X ? y : x);
 
 		/* In the tunnel entrance? */
 		if (5 <= pos && pos <= 10) return z;
 	} else {
-		DiagDirection dir = GetBridgeRampDirection(tile);
+		DiagDirection dir = GetTunnelBridgeDirection(tile);
 		uint pos = (DiagDirToAxis(dir) == AXIS_X ? y : x);
 
 		z += ApplyFoundationToSlope(GetBridgeFoundation(tileh, DiagDirToAxis(dir)), &tileh);
@@ -1200,7 +1201,7 @@ static uint GetSlopeZ_TunnelBridge(TileIndex tile, uint x, uint y)
 
 static Foundation GetFoundation_TunnelBridge(TileIndex tile, Slope tileh)
 {
-	return IsTunnel(tile) ? FOUNDATION_NONE : GetBridgeFoundation(tileh, DiagDirToAxis(GetBridgeRampDirection(tile)));
+	return IsTunnel(tile) ? FOUNDATION_NONE : GetBridgeFoundation(tileh, DiagDirToAxis(GetTunnelBridgeDirection(tile)));
 }
 
 
@@ -1244,10 +1245,10 @@ static const StringID _bridge_tile_str[(MAX_BRIDGES + 3) + (MAX_BRIDGES + 3)] =
 static void GetTileDesc_TunnelBridge(TileIndex tile, TileDesc *td)
 {
 	if (IsTunnel(tile)) {
-		td->str = (GetTunnelTransportType(tile) == TRANSPORT_RAIL) ?
+		td->str = (GetTunnelBridgeTransportType(tile) == TRANSPORT_RAIL) ?
 			STR_5017_RAILROAD_TUNNEL : STR_5018_ROAD_TUNNEL;
 	} else {
-		td->str = _bridge_tile_str[GetBridgeTransportType(tile) << 4 | GetBridgeType(tile)];
+		td->str = _bridge_tile_str[GetTunnelBridgeTransportType(tile) << 4 | GetBridgeType(tile)];
 	}
 	td->owner = GetTileOwner(tile);
 }
@@ -1260,14 +1261,14 @@ static void AnimateTile_TunnelBridge(TileIndex tile)
 
 static void TileLoop_TunnelBridge(TileIndex tile)
 {
-	bool snow_or_desert = IsTunnelTile(tile) ? HasTunnelSnowOrDesert(tile) : HasBridgeSnowOrDesert(tile);
+	bool snow_or_desert = IsTunnelTile(tile) ? HasTunnelBridgeSnowOrDesert(tile) : HasTunnelBridgeSnowOrDesert(tile);
 	switch (_opt.landscape) {
 		case LT_ARCTIC:
 			if (snow_or_desert != (GetTileZ(tile) > GetSnowLine())) {
 				if (IsTunnelTile(tile)) {
-					SetTunnelSnowOrDesert(tile, !snow_or_desert);
+					SetTunnelBridgeSnowOrDesert(tile, !snow_or_desert);
 				} else {
-					SetBridgeSnowOrDesert(tile, !snow_or_desert);
+					SetTunnelBridgeSnowOrDesert(tile, !snow_or_desert);
 				}
 				MarkTileDirtyByTile(tile);
 			}
@@ -1276,9 +1277,9 @@ static void TileLoop_TunnelBridge(TileIndex tile)
 		case LT_TROPIC:
 			if (GetTropicZone(tile) == TROPICZONE_DESERT && !snow_or_desert) {
 				if (IsTunnelTile(tile)) {
-					SetTunnelSnowOrDesert(tile, true);
+					SetTunnelBridgeSnowOrDesert(tile, true);
 				} else {
-					SetBridgeSnowOrDesert(tile, true);
+					SetTunnelBridgeSnowOrDesert(tile, true);
 				}
 				MarkTileDirtyByTile(tile);
 			}
@@ -1295,13 +1296,13 @@ static void ClickTile_TunnelBridge(TileIndex tile)
 static uint32 GetTileTrackStatus_TunnelBridge(TileIndex tile, TransportType mode, uint sub_mode)
 {
 	if (IsTunnel(tile)) {
-		if (GetTunnelTransportType(tile) != mode) return 0;
-		if (GetTunnelTransportType(tile) == TRANSPORT_ROAD && (GetRoadTypes(tile) & sub_mode) == 0) return 0;
-		return AxisToTrackBits(DiagDirToAxis(GetTunnelDirection(tile))) * 0x101;
+		if (GetTunnelBridgeTransportType(tile) != mode) return 0;
+		if (GetTunnelBridgeTransportType(tile) == TRANSPORT_ROAD && (GetRoadTypes(tile) & sub_mode) == 0) return 0;
+		return AxisToTrackBits(DiagDirToAxis(GetTunnelBridgeDirection(tile))) * 0x101;
 	} else {
-		if (GetBridgeTransportType(tile) != mode) return 0;
-		if (GetBridgeTransportType(tile) == TRANSPORT_ROAD && (GetRoadTypes(tile) & sub_mode) == 0) return 0;
-		return AxisToTrackBits(DiagDirToAxis(GetBridgeRampDirection(tile))) * 0x101;
+		if (GetTunnelBridgeTransportType(tile) != mode) return 0;
+		if (GetTunnelBridgeTransportType(tile) == TRANSPORT_ROAD && (GetRoadTypes(tile) & sub_mode) == 0) return 0;
+		return AxisToTrackBits(DiagDirToAxis(GetTunnelBridgeDirection(tile))) * 0x101;
 	}
 }
 
@@ -1317,7 +1318,7 @@ static void ChangeTileOwner_TunnelBridge(TileIndex tile, PlayerID old_player, Pl
 			 * the bridge/tunnel. As all *our* vehicles are already removed, they
 			 * must be of another owner. Therefor this must be a road bridge/tunnel.
 			 * In that case we can safely reassign the ownership to OWNER_NONE. */
-			assert((IsTunnel(tile) ? GetTunnelTransportType(tile) : GetBridgeTransportType(tile)) == TRANSPORT_ROAD);
+			assert((IsTunnel(tile) ? GetTunnelBridgeTransportType(tile) : GetTunnelBridgeTransportType(tile)) == TRANSPORT_ROAD);
 			SetTileOwner(tile, OWNER_NONE);
 		}
 	}
@@ -1354,7 +1355,7 @@ static uint32 VehicleEnter_TunnelBridge(Vehicle *v, TileIndex tile, int x, int y
 		if (v->type == VEH_TRAIN) {
 			fc = (x & 0xF) + (y << 4);
 
-			dir = GetTunnelDirection(tile);
+			dir = GetTunnelBridgeDirection(tile);
 			vdir = DirToDiagDir(v->direction);
 
 			if (v->u.rail.track != TRACK_BIT_WORMHOLE && dir == vdir) {
@@ -1382,7 +1383,7 @@ static uint32 VehicleEnter_TunnelBridge(Vehicle *v, TileIndex tile, int x, int y
 			}
 		} else if (v->type == VEH_ROAD) {
 			fc = (x & 0xF) + (y << 4);
-			dir = GetTunnelDirection(tile);
+			dir = GetTunnelBridgeDirection(tile);
 			vdir = DirToDiagDir(v->direction);
 
 			/* Enter tunnel? */
@@ -1422,7 +1423,7 @@ static uint32 VehicleEnter_TunnelBridge(Vehicle *v, TileIndex tile, int x, int y
 			if (v->cur_speed > spd) v->cur_speed = spd;
 		}
 
-		dir = GetBridgeRampDirection(tile);
+		dir = GetTunnelBridgeDirection(tile);
 		if (DirToDiagDir(v->direction) == dir) {
 			switch (dir) {
 				default: NOT_REACHED();
@@ -1462,7 +1463,7 @@ static uint32 VehicleEnter_TunnelBridge(Vehicle *v, TileIndex tile, int x, int y
 static CommandCost TerraformTile_TunnelBridge(TileIndex tile, uint32 flags, uint z_new, Slope tileh_new)
 {
 	if (_patches.build_on_slopes && AutoslopeEnabled() && IsBridge(tile)) {
-		DiagDirection direction = GetBridgeRampDirection(tile);
+		DiagDirection direction = GetTunnelBridgeDirection(tile);
 		Axis axis = DiagDirToAxis(direction);
 		CommandCost res;
 
diff --git a/src/tunnelbridge_map.h b/src/tunnelbridge_map.h
new file mode 100644
index 000000000..dda1cc258
--- /dev/null
+++ b/src/tunnelbridge_map.h
@@ -0,0 +1,68 @@
+/* $Id$ */
+
+/** @file tunnelbridge_map.h Functions that have tunnels and bridges in common */
+
+#ifndef TUNNELBRIDGE_MAP_H
+#define TUNNELBRIDGE_MAP_H
+
+#include "direction.h"            /* DiagDirection */
+#include "core/bitmath_func.hpp"  /* GB, HasBit, SB */
+#include "map.h"                  /* Tile, TileIndex */
+#include "tile.h"                 /* TileType, IsTileType */
+#include "openttd.h"              /* TransportType */
+
+
+/**
+ * Tunnel: Get the direction facing out of the tunnel
+ * Bridge: Get the direction pointing onto the bridge
+ * @param t The tile to analyze
+ * @pre IsTileType(t, MP_TUNNELBRIDGE)
+ * @return the above mentionned direction
+ */
+static inline DiagDirection GetTunnelBridgeDirection(TileIndex t)
+{
+	assert(IsTileType(t, MP_TUNNELBRIDGE));
+	return (DiagDirection)GB(_m[t].m5, 0, 2);
+}
+
+/**
+ * Tunnel: Get the transport type of the tunnel (road or rail)
+ * Bridge: Get the transport type of the bridge's ramp
+ * @param t The tile to analyze
+ * @pre IsTileType(t, MP_TUNNELBRIDGE)
+ * @return the transport type in the tunnel/bridge
+ */
+static inline TransportType GetTunnelBridgeTransportType(TileIndex t)
+{
+	assert(IsTileType(t, MP_TUNNELBRIDGE));
+	return (TransportType)GB(_m[t].m5, 2, 2);
+}
+
+/**
+ * Tunnel: Is this tunnel entrance in a snowy or desert area?
+ * Bridge: Does the bridge ramp lie in a snow or desert area?
+ * @param t The tile to analyze
+ * @pre IsTileType(t, MP_TUNNELBRIDGE)
+ * @return true if and only if the tile is in a snowy/desert area
+ */
+static inline bool HasTunnelBridgeSnowOrDesert(TileIndex t)
+{
+	assert(IsTileType(t, MP_TUNNELBRIDGE));
+	return HasBit(_m[t].m4, 7);
+}
+
+/**
+ * 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.
+ * @param t the tunnel entrance / bridge ramp tile
+ * @param snow_or_desert is the entrance/ramp in snow or desert (true), when
+ *                       not in snow and not in desert false
+ * @pre IsTileType(t, MP_TUNNELBRIDGE)
+ */
+static inline void SetTunnelBridgeSnowOrDesert(TileIndex t, bool snow_or_desert)
+{
+	assert(IsTileType(t, MP_TUNNELBRIDGE));
+	SB(_m[t].m4, 7, 1, snow_or_desert);
+}
+
+#endif /* TUNNELBRIDGE_MAP_H */
diff --git a/src/yapf/follow_track.hpp b/src/yapf/follow_track.hpp
index 75fff5109..1b1fc2bfb 100644
--- a/src/yapf/follow_track.hpp
+++ b/src/yapf/follow_track.hpp
@@ -78,7 +78,7 @@ protected:
 
 		// extra handling for tunnels in our direction
 		if (IsTunnelTile(m_old_tile)) {
-			DiagDirection tunnel_enterdir = GetTunnelDirection(m_old_tile);
+			DiagDirection tunnel_enterdir = GetTunnelBridgeDirection(m_old_tile);
 			if (tunnel_enterdir == m_exitdir) {
 				// we are entering the tunnel
 				FindLengthOfTunnelResult flotr = FindLengthOfTunnel(m_old_tile, m_exitdir);
@@ -92,7 +92,7 @@ protected:
 
 		// extra handling for bridge ramp in our direction
 		if (IsBridgeTile(m_old_tile)) {
-			DiagDirection bridge_enterdir = GetBridgeRampDirection(m_old_tile);
+			DiagDirection bridge_enterdir = GetTunnelBridgeDirection(m_old_tile);
 			if (bridge_enterdir == m_exitdir) {
 				// we are entering the bridge ramp
 				m_new_tile = GetOtherBridgeEnd(m_old_tile);
@@ -208,7 +208,7 @@ protected:
 		if (!IsWaterTT() && IsTileType(m_new_tile, MP_TUNNELBRIDGE)) {
 			if (IsTunnel(m_new_tile)) {
 				if (!m_is_tunnel) {
-					DiagDirection tunnel_enterdir = GetTunnelDirection(m_new_tile);
+					DiagDirection tunnel_enterdir = GetTunnelBridgeDirection(m_new_tile);
 					if (tunnel_enterdir != m_exitdir) {
 						m_err = EC_NO_WAY;
 						return false;
@@ -216,7 +216,7 @@ protected:
 				}
 			} else if (IsBridge(m_new_tile)) {
 				if (!m_is_bridge) {
-					DiagDirection ramp_enderdir = GetBridgeRampDirection(m_new_tile);
+					DiagDirection ramp_enderdir = GetTunnelBridgeDirection(m_new_tile);
 					if (ramp_enderdir != m_exitdir) {
 						m_err = EC_NO_WAY;
 						return false;
diff --git a/src/yapf/yapf.hpp b/src/yapf/yapf.hpp
index f98a7c607..2bbbc0a7a 100644
--- a/src/yapf/yapf.hpp
+++ b/src/yapf/yapf.hpp
@@ -12,6 +12,7 @@
 #include "../road_map.h"
 #include "../tunnel_map.h"
 #include "../bridge_map.h"
+#include "../tunnelbridge_map.h"
 #include "../bridge.h"
 #include "../station.h"
 #include "../station_map.h"
diff --git a/src/yapf/yapf_costbase.hpp b/src/yapf/yapf_costbase.hpp
index df4d9e787..2793aab9f 100644
--- a/src/yapf/yapf_costbase.hpp
+++ b/src/yapf/yapf_costbase.hpp
@@ -11,7 +11,7 @@ struct CYapfCostBase {
 		if (IsDiagonalTrackdir(td)) {
 			if (IsBridgeTile(tile)) {
 				// it is bridge ramp, check if we are entering the bridge
-				if (GetBridgeRampDirection(tile) != TrackdirToExitdir(td)) return false; // no, we are living it, no penalty
+				if (GetTunnelBridgeDirection(tile) != TrackdirToExitdir(td)) return false; // no, we are living it, no penalty
 				// we are entering the bridge
 				// if the tile slope is downwards, then bridge ramp has not upward slope
 				uint tile_slope = GetTileSlope(tile, NULL) & 0x0F;