* Make NPFDistanceTrack return the distance multiplied by NPF_TILE_LENGTH to prevent rounding
This should make ship and train pathfinding more accurate and faster.
* Update IsEndOfLine to prevent trains from trying to go off a slope onto a tunnel entrance.
- Feature: [pbs] Implement autoplacement of pbs blocks, when a block has an entry and an exit pbs signal, covert the entire block to pbs. Can be turned off in the patch settings.
- Feature: [pbs] Allow showing of reserved status by making the tracks darker, when the pbs debug level is at least 1.
- Codechange: [NPF] Check the railtype along a route against the engine type instead of against the previouse tile. This clears the way for electriefied rails.
- Add: [NPF] [ 1209644 ] A penalty for crossings (peter1138)
- Fix: [ 1203769 ] [NPF] NPF tries to plan over bridges, through tunnels, over level crossings of other players. (glx)
- Codechange: Renamed TRANSPORT_MAX to TRANSPORT_END and added INVALID_TRANSPORT.
- Codechange: Moved IsLevelCrossing() from tile.h to rail.h
- Add: GetCrossingTransportType(), which returns the transport type (road, rail) of both tracks on a level crossing.
- Removed old TODO that was fulfilled already.
* Codechange: Made npf.c use some map array accessing wrappers instead of direct access.
* Codechange/Fix: Named every enum in tile.h. Fixes a nasty bug on MSVC where arrays would be initialised with zeroes (tnx Asterix_)
* Removed magic numbers from tables in tile.c.
* Added some explicit casts in tile.h.
* 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.
