(svn r5070) Merged the bridge branch

-Feature: Bridges can now be placed above:
	Any railway track combination (excluding depots and waypoints)
	Any road combination (excluding depots)
	Clear tiles (duh), including fields
	Tunnel entrances
	Bridge heads

Thanks to Tron for idea and implementation, KUDr for the yapf synchronization and many others for hours of testing

There are still a number of visual problems remaining, especially when electric railways are on or under the bridge.
DO NOT REPORT THOSE BUGS FOR THE TIME BEING please.

1 files changed, 57 insertions, 42 deletions

diff --git a/pathfind.c b/pathfind.c
index 622b820f0..77bc9804a 100644
--- a/pathfind.c
+++ b/pathfind.c
@@ -256,21 +256,27 @@ static void TPFMode1(TrackPathFinder* tpf, TileIndex tile, DiagDirection directi
 	RememberData rd;
 	TileIndex tile_org = tile;
 
-	// check if the old tile can be left at that direction
-	if (tpf->tracktype == TRANSPORT_ROAD) {
-		// road stops and depots now have a track (r4419)
-		// don't enter road stop from the back
-		if (IsRoadStopTile(tile) && GetRoadStopDir(tile) != direction) return;
-		// don't enter road depot from the back
-		if (IsTileDepotType(tile, TRANSPORT_ROAD) && GetRoadDepotDirection(tile) != direction) return;
-	}
-
-	if (IsTunnelTile(tile)) {
-		if (GetTunnelDirection(tile) != direction ||
-				GetTunnelTransportType(tile) != tpf->tracktype) {
-			return;
+	if (IsTileType(tile, MP_TUNNELBRIDGE)) {
+		if (IsTunnel(tile)) {
+			if (GetTunnelDirection(tile) != direction ||
+					GetTunnelTransportType(tile) != tpf->tracktype) {
+				return;
+			}
+			tile = SkipToEndOfTunnel(tpf, tile, direction);
+		} else {
+			TileIndex tile_end;
+			if (GetBridgeRampDirection(tile) != direction ||
+					GetBridgeTransportType(tile) != tpf->tracktype) {
+				return;
+			}
+			//fprintf(stderr, "%s: Planning over bridge\n", __func__);
+			// TODO doesn't work - WHAT doesn't work?
+			TPFSetTileBit(tpf, tile, 14);
+			tile_end = GetOtherBridgeEnd(tile);
+			tpf->rd.cur_length += DistanceManhattan(tile, tile_end);
+			tile = tile_end;
+			TPFSetTileBit(tpf, tile, 14);
 		}
-		tile = SkipToEndOfTunnel(tpf, tile, direction);
 	}
 	tile += TileOffsByDir(direction);
 
@@ -281,11 +287,7 @@ static void TPFMode1(TrackPathFinder* tpf, TileIndex tile, DiagDirection directi
 
 		if (IsTileType(tile_org, MP_RAILWAY) || IsTileType(tile_org, MP_STATION) || IsTileType(tile_org, MP_TUNNELBRIDGE))
 			if (IsTileType(tile, MP_RAILWAY) || IsTileType(tile, MP_STATION) || IsTileType(tile, MP_TUNNELBRIDGE))
-				/* Check if we are on a bridge (middle parts don't have an owner */
-				if (!IsBridgeTile(tile) || !IsBridgeMiddle(tile))
-					if (!IsBridgeTile(tile_org) || !IsBridgeMiddle(tile_org))
-						if (GetTileOwner(tile_org) != GetTileOwner(tile))
-							return;
+				if (GetTileOwner(tile_org) != GetTileOwner(tile)) return;
 	}
 
 	// check if the new tile can be entered from that direction
@@ -673,7 +675,6 @@ static void NTPEnum(NewTrackPathFinder* tpf, TileIndex tile, DiagDirection direc
 	uint track;
 	TileIndex tile_org;
 	StackedItem si;
-	FindLengthOfTunnelResult flotr;
 	int estimation;
 
 
@@ -711,22 +712,40 @@ callback_and_continue:
 start_at:
 		// If the tile is the entry tile of a tunnel, and we're not going out of the tunnel,
 		//   need to find the exit of the tunnel.
-		if (IsTunnelTile(tile) &&
-				GetTunnelDirection(tile) != ReverseDiagDir(direction)) {
-			/* We are not just driving out of the tunnel */
-			if (GetTunnelDirection(tile) != direction ||
-					GetTunnelTransportType(tile) != tpf->tracktype) {
-				// We are not driving into the tunnel, or it is an invalid tunnel
-				continue;
-			}
-			if (!HASBIT(tpf->railtypes, GetRailType(tile))) {
-				bits = 0;
-				break;
+		if (IsTileType(tile, MP_TUNNELBRIDGE)) {
+			if (IsTunnel(tile)) {
+				if (GetTunnelDirection(tile) != ReverseDiagDir(direction)) {
+					FindLengthOfTunnelResult flotr;
+
+					/* We are not just driving out of the tunnel */
+					if (GetTunnelDirection(tile) != direction ||
+							GetTunnelTransportType(tile) != tpf->tracktype) {
+						// We are not driving into the tunnel, or it is an invalid tunnel
+						continue;
+					}
+					if (!HASBIT(tpf->railtypes, GetRailType(tile))) {
+						bits = 0;
+						break;
+					}
+					flotr = FindLengthOfTunnel(tile, direction);
+					si.cur_length += flotr.length * DIAG_FACTOR;
+					tile = flotr.tile;
+					// tile now points to the exit tile of the tunnel
+				}
+			} else {
+				TileIndex tile_end;
+				if (GetBridgeRampDirection(tile) != ReverseDiagDir(direction)) {
+					// We are not just leaving the bridge
+					if (GetBridgeRampDirection(tile) != direction ||
+							GetBridgeTransportType(tile) != tpf->tracktype) {
+						// Not entering the bridge or not compatible
+						continue;
+					}
+				}
+				tile_end = GetOtherBridgeEnd(tile);
+				si.cur_length += DistanceManhattan(tile, tile_end) * DIAG_FACTOR;
+				tile = tile_end;
 			}
-			flotr = FindLengthOfTunnel(tile, direction);
-			si.cur_length += flotr.length * DIAG_FACTOR;
-			tile = flotr.tile;
-			// tile now points to the exit tile of the tunnel
 		}
 
 		// This is a special loop used to go through
@@ -754,13 +773,9 @@ start_at:
 				// Check that the tile contains exactly one track
 				if (bits == 0 || KILL_FIRST_BIT(bits) != 0) break;
 
-				/* Check the rail type only if the train is *NOT* on top of
-				 * a bridge. */
-				if (!(IsBridgeTile(tile) && IsBridgeMiddle(tile) && GetBridgeAxis(tile) == DiagDirToAxis(direction))) {
-					if (IsTileType(tile, MP_STREET) ? !HASBIT(tpf->railtypes, GetRailTypeCrossing(tile)) : !HASBIT(tpf->railtypes, GetRailType(tile))) {
-						bits = 0;
-						break;
-					}
+				if (IsTileType(tile, MP_STREET) ? !HASBIT(tpf->railtypes, GetRailTypeCrossing(tile)) : !HASBIT(tpf->railtypes, GetRailType(tile))) {
+					bits = 0;
+					break;
 				}
 
 				///////////////////