(svn r2448) General cleanup of rail related code, more to follow.

* Add: rail.[ch] for rail-related enums and wrapper functions.
* Codechange: Removed dozens of magic numbers with below enums.
* Codechange: Rewrote CheckTrackCombination().
* Add: TILE_SIZE, TILE_PIXELS and TILE_HEIGHT constants.
* Add: enums RailTileType, RailTileSubtype, SignalType to mask against the map arrays.
* Add: enums Track, TrackBits, Trackdir, TrackdirBits for railway track data. (Note that the old RAIL_BIT constants are replaced by TRACK_BIT ones).
* Add: enums Direction and DiagDirection
* Codechange: Moved a bunch of track(dir) related lookup arrays from npf.[ch] to rail.[ch].
* Codechange: move RailType enum from tile.h to rail.h.
* Add: Wrapper functions for masking signal status in the map arrays: SignalAlongTrackdir, SignalAgainstTrackdir and SignalOnTrack.
* Add: Wrapper functions to access rail tiles, using above enums
* Add: Wrapper functions to modify tracks, trackdirs, directions, etc.
* Add: Wrapper functions for all lookup arrays in rail.[ch] (Arrays are still used in parts of the code)
* Codechange: Renamed some variables and arguments to better represent what they contain (railbit -> track, bits -> trackdirbits, etc.). 
* Codechange: Don't use FindLandscapeHeight() in CmdRemoveSingleRail(), since it returns way too much info. Use GetTileSlope() instead.
* Codechange: [NPF] Removed some unused globals and code from npf.c.

1 files changed, 2 insertions, 2 deletions

diff --git a/roadveh_cmd.c b/roadveh_cmd.c
index 1c7432786..7cde8e1ed 100644
--- a/roadveh_cmd.c
+++ b/roadveh_cmd.c
@@ -317,7 +317,7 @@ static Depot *FindClosestRoadDepot(Vehicle *v)
 	if (_patches.new_pathfinding_all) {
 		NPFFoundTargetData ftd;
 		/* See where we are now */
-		byte trackdir = GetVehicleTrackdir(v);
+		Trackdir trackdir = GetVehicleTrackdir(v);
 
 		ftd = NPFRouteToDepotBreadthFirst(v->tile, trackdir, TRANSPORT_ROAD, v->owner);
 		if (ftd.best_bird_dist == 0)
@@ -1101,7 +1101,7 @@ static int RoadFindPathToDest(Vehicle *v, uint tile, int enterdir)
 		byte trackdir;
 
 		NPFFillWithOrderData(&fstd, v);
-		trackdir = _dir_to_diag_trackdir[enterdir];
+		trackdir = DiagdirToDiagTrackdir(enterdir);
 		//debug("Finding path. Enterdir: %d, Trackdir: %d", enterdir, trackdir);
 
 		ftd = NPFRouteToStationOrTile(tile - TileOffsByDir(enterdir), trackdir, &fstd, TRANSPORT_ROAD, v->owner);