1

#ifndef RAIL_H

     2

#define RAIL_H

     3

     4

#include "tile.h"

     5

     6

/*

     7

 * Some enums for accesing the map bytes for rail tiles

     8

 */

     9

    10

/* These types are used in the map5 byte for rail tiles. Use GetRailTileType() to

    11

 * get these values */

    12

typedef enum RailTileTypes {

    13

	RAIL_TYPE_NORMAL         = 0x0,

    14

	RAIL_TYPE_SIGNALS        = 0x40,

    15

	RAIL_TYPE_UNUSED         = 0x80, /* XXX: Maybe this could become waypoints? */

    16

	RAIL_TYPE_DEPOT_WAYPOINT = 0xC0, /* Is really depots and waypoints... */

    17

	RAIL_TILE_TYPE_MASK      = 0xC0,

    18

} RailTileType;

    19

    20

enum { /* DEPRECATED TODO: Rewrite all uses of this */

    21

	RAIL_TYPE_SPECIAL = 0x80, /* This used to say "If this bit is set, then it's

    22

														 * not a regular track.", but currently, you

    23

														 * should rather view map5[6..7] as one type,

    24

														 * containing a value from RailTileTypes above.

    25

														 * This value is only maintained for backwards

    26

														 * compatibility */

    27

    28

	/* There used to be RAIL_BIT_* enums here, they moved to (for now) npf.c as

    29

	 * TRACK_BIT_* */

    30

};

    31

    32

/* These subtypes are used in the map5 byte when the main rail type is

    33

 * RAIL_TYPE_DEPOT_WAYPOINT */

    34

typedef enum RailTileSubtypes {

    35

	RAIL_SUBTYPE_DEPOT    = 0x00,

    36

	RAIL_SUBTYPE_WAYPOINT = 0x04,

    37

	RAIL_SUBTYPE_MASK     = 0x3C,

    38

} RailTileSubtype;

    39

    40

typedef enum SignalTypes {

    42

  SIGTYPE_NORMAL  = 0,        // normal signal

    43

  SIGTYPE_ENTRY   = 1,        // presignal block entry

    44

  SIGTYPE_EXIT    = 2,        // presignal block exit

    45

  SIGTYPE_COMBO   = 3,        // presignal inter-block

    46

	SIGTYPE_PBS     = 4,        // pbs signal

    47

	SIGTYPE_END,

    48

	SIGTYPE_MASK    = 7,

    49

} SignalType;

    50

    51

typedef enum RailTypes {

    52

	RAILTYPE_RAIL   = 0,

    53

	RAILTYPE_MONO   = 1,

    54

	RAILTYPE_MAGLEV = 2,

    55

	RAILTYPE_END,

    56

	RAILTYPE_MASK   = 0x3,

    57

	INVALID_RAILTYPE = 0xFF,

    58

} RailType;

    59

    60

enum {

    61

	SIG_SEMAPHORE_MASK = 1 << 3,

    62

};

    63

    64

/* These are used to specify a single track. Can be translated to a trackbit

    65

 * with TrackToTrackbit */

    66

typedef enum Tracks {

    67

  TRACK_DIAG1 = 0,

    68

  TRACK_DIAG2 = 1,

    69

  TRACK_UPPER = 2,

    70

  TRACK_LOWER = 3,

    71

  TRACK_LEFT  = 4,

    72

  TRACK_RIGHT = 5,

    73

  TRACK_END,

    74

  INVALID_TRACK = 0xFF,

    75

} Track;

    76

    77

/* These are the bitfield variants of the above */

    78

typedef enum TrackBits {

    79

  TRACK_BIT_DIAG1 = 1,  // 0

    80

  TRACK_BIT_DIAG2 = 2,  // 1

    81

  TRACK_BIT_UPPER = 4,  // 2

    82

  TRACK_BIT_LOWER = 8,  // 3

    83

  TRACK_BIT_LEFT  = 16, // 4

    84

  TRACK_BIT_RIGHT = 32, // 5

    85

	TRACK_BIT_MASK  = 0x3F,

    86

} TrackBits;

    87

    88

/* These are a combination of tracks and directions. Values are 0-5 in one

    89

direction (corresponding to the Track enum) and 8-13 in the other direction. */

    90

typedef enum Trackdirs {

    91

  TRACKDIR_DIAG1_NE = 0,

    92

  TRACKDIR_DIAG2_SE = 1,

    93

  TRACKDIR_UPPER_E  = 2,

    94

  TRACKDIR_LOWER_E  = 3,

    95

  TRACKDIR_LEFT_S   = 4,

    96

  TRACKDIR_RIGHT_S  = 5,

    97

	/* Note the two missing values here. This enables trackdir -> track

    98

	 * conversion by doing (trackdir & 7) */

    99

  TRACKDIR_DIAG1_SW = 8,

   100

  TRACKDIR_DIAG2_NW = 9,

   101

  TRACKDIR_UPPER_W  = 10,

   102

  TRACKDIR_LOWER_W  = 11,

   103

  TRACKDIR_LEFT_N   = 12,

   104

  TRACKDIR_RIGHT_N  = 13,

   105

  TRACKDIR_END,

   106

  INVALID_TRACKDIR  = 0xFF,

   107

} Trackdir;

   108

   109

/* These are a combination of tracks and directions. Values are 0-5 in one

   110

direction (corresponding to the Track enum) and 8-13 in the other direction. */

   111

typedef enum TrackdirBits {

   112

  TRACKDIR_BIT_DIAG1_NE = 0x1,

   113

  TRACKDIR_BIT_DIAG2_SE = 0x2,

   114

  TRACKDIR_BIT_UPPER_E  = 0x4,

   115

  TRACKDIR_BIT_LOWER_E  = 0x8,

   116

  TRACKDIR_BIT_LEFT_S   = 0x10,

   117

  TRACKDIR_BIT_RIGHT_S  = 0x20,

   118

	/* Again, note the two missing values here. This enables trackdir -> track conversion by doing (trackdir & 0xFF) */

   119

  TRACKDIR_BIT_DIAG1_SW = 0x0100,

   120

  TRACKDIR_BIT_DIAG2_NW = 0x0200,

   121

  TRACKDIR_BIT_UPPER_W  = 0x0400,

   122

  TRACKDIR_BIT_LOWER_W  = 0x0800,

   123

  TRACKDIR_BIT_LEFT_N   = 0x1000,

   124

  TRACKDIR_BIT_RIGHT_N  = 0x2000,

   125

	TRACKDIR_BIT_MASK			= 0x3F3F,

   126

  INVALID_TRACKDIR_BIT  = 0xFFFF,

   127

} TrackdirBits;

   128

   129

/* These are states in which a signal can be. Currently these are only two, so

   130

 * simple boolean logic will do. But do try to compare to this enum instead of

   131

 * normal boolean evaluation, since that will make future additions easier.

   132

 */

   133

typedef enum SignalStates {

   134

	SIGNAL_STATE_RED = 0,

   135

	SIGNAL_STATE_GREEN = 1,

   136

} SignalState;

   137

   138

// these are the maximums used for updating signal blocks, and checking if a depot is in a pbs block

   139

enum {

   140

	NUM_SSD_ENTRY = 256, // max amount of blocks

   141

	NUM_SSD_STACK = 32 ,// max amount of blocks to check recursively

   142

};

   143

   144

/**

   145

 * Maps a Trackdir to the corresponding TrackdirBits value

   146

 */

   147

static inline TrackdirBits TrackdirToTrackdirBits(Trackdir trackdir) { return (TrackdirBits)(1 << trackdir); }

   148

   149

/*

   150

 * These functions check the validity of Tracks and Trackdirs. assert against

   151

 * them when convenient.

   152

 */

   153

static inline bool IsValidTrack(Track track) { return track < TRACK_END; }

   154

static inline bool IsValidTrackdir(Trackdir trackdir) { return (TrackdirToTrackdirBits(trackdir) & TRACKDIR_BIT_MASK) != 0; }

   155

   156

/*

   157

 * Functions to map tracks to the corresponding bits in the signal

   158

 * presence/status bytes in the map. You should not use these directly, but

   159

 * wrapper functions below instead. XXX: Which are these?

   160

 */

   161

   162

/**

   163

 * Maps a trackdir to the bit that stores its status in the map arrays, in the

   164

 * direction along with the trackdir.

   165

 */

   166

extern const byte _signal_along_trackdir[TRACKDIR_END];

   167

static inline byte SignalAlongTrackdir(Trackdir trackdir) {return _signal_along_trackdir[trackdir];}

   168

   169

/**

   170

 * Maps a trackdir to the bit that stores its status in the map arrays, in the

   171

 * direction against the trackdir.

   172

 */

   173

static inline byte SignalAgainstTrackdir(Trackdir trackdir) {

   174

	extern const byte _signal_against_trackdir[TRACKDIR_END];

   175

	return _signal_against_trackdir[trackdir];

   176

}

   177

   178

/**

   179

 * Maps a Track to the bits that store the status of the two signals that can

   180

 * be present on the given track.

   181

 */

   182

static inline byte SignalOnTrack(Track track) {

   183

	extern const byte _signal_on_track[TRACK_END];

   184

	return _signal_on_track[track];

   185

}

   186

   187

/*

   188

 * Some functions to query rail tiles

   189

 */

   190

   191

/**

   192

 * Returns the RailTileType of a given rail tile. (ie normal, with signals,

   193

 * depot, etc.)

   194

 */

   195

static inline RailTileType GetRailTileType(TileIndex tile)

   196

{

   197

	assert(IsTileType(tile, MP_RAILWAY));

   199

}

   200

   201

/**

   202

 * Returns the rail type of the given rail tile (ie rail, mono, maglev).

   203

 */

   205

   206

/**

   207

 * Checks if a rail tile has signals.

   208

 */

   209

static inline bool HasSignals(TileIndex tile)

   210

{

   211

	return GetRailTileType(tile) == RAIL_TYPE_SIGNALS;

   212

}

   213

   214

/**

   215

 * Returns the RailTileSubtype of a given rail tile with type

   216

 * RAIL_TYPE_DEPOT_WAYPOINT

   217

 */

   218

static inline RailTileSubtype GetRailTileSubtype(TileIndex tile)

   219

{

   220

	assert(GetRailTileType(tile) == RAIL_TYPE_DEPOT_WAYPOINT);

   222

}

   223

   224

/**

   225

 * Returns whether this is plain rails, with or without signals. Iow, if this

   226

 * tiles RailTileType is RAIL_TYPE_NORMAL or RAIL_TYPE_SIGNALS.

   227

 */

   228

static inline bool IsPlainRailTile(TileIndex tile)

   229

{

   230

	RailTileType rtt = GetRailTileType(tile);

   231

	return rtt == RAIL_TYPE_NORMAL || rtt == RAIL_TYPE_SIGNALS;

   232

}

   233

   234

/**

   235

 * Returns the tracks present on the given plain rail tile (IsPlainRailTile())

   236

 */

   237

static inline TrackBits GetTrackBits(TileIndex tile)

   238

{

   239

	assert(GetRailTileType(tile) == RAIL_TYPE_NORMAL || GetRailTileType(tile) == RAIL_TYPE_SIGNALS);

   241

}

   242

   243

/**

   244

 * Returns whether the given track is present on the given tile. Tile must be

   245

 * a plain rail tile (IsPlainRailTile()).

   246

 */

   247

static inline bool HasTrack(TileIndex tile, Track track)

   248

{

   249

	assert(IsValidTrack(track));

   250

	return HASBIT(GetTrackBits(tile), track);

   251

}

   252

   253

/*

   254

 * Functions describing logical relations between Tracks, TrackBits, Trackdirs

   255

 * TrackdirBits, Direction and DiagDirections.

   256

 *

   257

 * TODO: Add #unndefs or something similar to remove the arrays used below

   258

 * from the global scope and expose direct uses of them.

   259

 */

   260

   261

/**

   262

 * Maps a trackdir to the reverse trackdir.

   263

 */

   264

static inline Trackdir ReverseTrackdir(Trackdir trackdir) {

   265

	extern const Trackdir _reverse_trackdir[TRACKDIR_END];

   266

	return _reverse_trackdir[trackdir];

   267

}

   268

   269

/*

   270

 * Maps a Track to the corresponding TrackBits value

   271

 */

   272

static inline TrackBits TrackToTrackBits(Track track) { return (TrackBits)(1 << track); }

   273

   274

/* Returns the Track that a given Trackdir represents */

   275

static inline Track TrackdirToTrack(Trackdir trackdir) { return (Track)(trackdir & 0x7); }

   276

   277

/* Returns a Trackdir for the given Track. Since every Track corresponds to

   278

 * two Trackdirs, we choose the one which points between NE and S.

   279

 * Note that the actual implementation is quite futile, but this might change

   280

 * in the future.

   281

 */

   282

static inline Trackdir TrackToTrackdir(Track track) { return (Trackdir)track; }

   283

   284

/* Returns a TrackdirBit mask that contains the two TrackdirBits that

   285

 * correspond with the given Track (one for each direction).

   286

 */

   287

static inline TrackdirBits TrackToTrackdirBits(Track track) { Trackdir td = TrackToTrackdir(track); return TrackdirToTrackdirBits(td) | TrackdirToTrackdirBits(ReverseTrackdir(td));}

   288

   289

/**

   290

 * Maps a trackdir to the trackdir that you will end up on if you go straight

   291

 * ahead. This will be the same trackdir for diagonal trackdirs, but a

   292

 * different (alternating) one for straight trackdirs

   293

 */

   294

static inline Trackdir NextTrackdir(Trackdir trackdir) {

   295

	extern const Trackdir _next_trackdir[TRACKDIR_END];

   296

	return _next_trackdir[trackdir];

   297

}

   298

   299

/**

   300

 * Maps a track to all tracks that make 90 deg turns with it.

   301

 */

   302

static inline TrackBits TrackCrossesTracks(Track track) {

   303

	extern const TrackBits _track_crosses_tracks[TRACK_END];

   304

	return _track_crosses_tracks[track];

   305

}

   306

   307

/**

   308

 * Maps a trackdir to the (4-way) direction the tile is exited when following

   309

 * that trackdir.

   310

 */

   311

static inline DiagDirection TrackdirToExitdir(Trackdir trackdir) {

   312

	extern const DiagDirection _trackdir_to_exitdir[TRACKDIR_END];

   313

	return _trackdir_to_exitdir[trackdir];

   314

}

   315

   316

/**

   317

 * Maps a track and an (4-way) dir to the trackdir that represents the track

   318

 * with the exit in the given direction.

   319

 */

   320

static inline Trackdir TrackExitdirToTrackdir(Track track, DiagDirection diagdir) {

   321

	extern const Trackdir _track_exitdir_to_trackdir[TRACK_END][DIAGDIR_END];

   322

	return _track_exitdir_to_trackdir[track][diagdir];

   323

}

   324

   325

/**

   326

 * Maps a track and an (4-way) dir to the trackdir that represents the track

   327

 * with the exit in the given direction.

   328

 */

   329

static inline Trackdir TrackEnterdirToTrackdir(Track track, DiagDirection diagdir) {

   330

	extern const Trackdir _track_enterdir_to_trackdir[TRACK_END][DIAGDIR_END];

   331

	return _track_enterdir_to_trackdir[track][diagdir];

   332

}

   333

   334

/**

   335

 * Maps a track and a full (8-way) direction to the trackdir that represents

   336

 * the track running in the given direction.

   337

 */

   338

static inline Trackdir TrackDirectionToTrackdir(Track track, Direction dir) {

   339

	extern const Trackdir _track_direction_to_trackdir[TRACK_END][DIR_END];

   340

	return _track_direction_to_trackdir[track][dir];

   341

}

   342

   343

/**

   344

 * Maps a (4-way) direction to the diagonal trackdir that runs in that

   345

 * direction.

   346

 */

   347

static inline Trackdir DiagdirToDiagTrackdir(DiagDirection diagdir) {

   348

	extern const Trackdir _dir_to_diag_trackdir[DIAGDIR_END];

   349

	return _dir_to_diag_trackdir[diagdir];

   350

}

   351

   352

/**

   353

 * Maps a trackdir to the trackdirs that can be reached from it (ie, when

   354

 * entering the next tile. This

   355

 */

   356

extern const TrackdirBits _exitdir_reaches_trackdirs[DIAGDIR_END];

   357

/* Note that there is no direct table for this function (there used to be),

   358

 * but it uses two simpeler tables to achieve the result */

   359

static inline TrackdirBits TrackdirReachesTrackdirs(Trackdir trackdir) { return _exitdir_reaches_trackdirs[TrackdirToExitdir(trackdir)]; }

   360

   361

/**

   362

 * Maps a trackdir to all trackdirs that make 90 deg turns with it.

   363

 */

   364

static inline TrackdirBits TrackdirCrossesTrackdirs(Trackdir trackdir) {

   365

	extern const TrackdirBits _track_crosses_trackdirs[TRACKDIR_END];

   366

	return _track_crosses_trackdirs[TrackdirToTrack(trackdir)];

   367

}

   368

   369

/**

   370

 * Maps a (4-way) direction to the reverse.

   371

 */

   372

static inline DiagDirection ReverseDiagdir(DiagDirection diagdir) {

   373

	extern const DiagDirection _reverse_diagdir[DIAGDIR_END];

   374

	return _reverse_diagdir[diagdir];

   375

}

   376

   377

/**

   378

 * Maps a (8-way) direction to a (4-way) DiagDirection

   379

 */

   380

static inline DiagDirection DirToDiagdir(Direction dir) {

   381

	assert(dir < DIR_END);

   382

	return (DiagDirection)(dir >> 1);

   383

}

   384

   385

/* Checks if a given Track is diagonal */

   386

static inline bool IsDiagonalTrack(Track track) { return (track == TRACK_DIAG1) || (track == TRACK_DIAG2); }

   387

   388

/* Checks if a given Trackdir is diagonal. */

   389

static inline bool IsDiagonalTrackdir(Trackdir trackdir) { return IsDiagonalTrack(TrackdirToTrack(trackdir)); }

   390

   391

/*

   392

 * Functions quering signals on tiles.

   393

 */

   394

   395

/**

   396

 * Checks for the presence of signals (either way) on the given track on the

   397

 * given rail tile.

   398

 */

   399

static inline bool HasSignalOnTrack(TileIndex tile, Track track)

   400

{

   401

	assert(IsValidTrack(track));

   403

}

   404

   405

/**

   406

 * Checks for the presence of signals along the given trackdir on the given

   407

 * rail tile.

   408

 *

   409

 * Along meaning if you are currently driving on the given trackdir, this is

   410

 * the signal that is facing us (for which we stop when it's red).

   411

 */

   412

static inline bool HasSignalOnTrackdir(TileIndex tile, Trackdir trackdir)

   413

{

   414

	assert (IsValidTrackdir(trackdir));

   416

}

   417

   418

/**

   419

 * Gets the state of the signal along the given trackdir.

   420

 *

   421

 * Along meaning if you are currently driving on the given trackdir, this is

   422

 * the signal that is facing us (for which we stop when it's red).

   423

 */

   424

static inline SignalState GetSignalState(TileIndex tile, Trackdir trackdir)

   425

{

   426

	assert(IsValidTrackdir(trackdir));

   427

	assert(HasSignalOnTrack(tile, TrackdirToTrack(trackdir)));

   429

}

   430

   431

/**

   432

 * Gets the type of signal on a given track on a given rail tile with signals.

   433

 *

   434

 * Note that currently, the track argument is not used, since

   435

 * signal types cannot be mixed. This function is trying to be

   436

 * future-compatible, though.

   437

 */

   438

static inline SignalType GetSignalType(TileIndex tile, Track track)

   439

{

   440

	assert(IsValidTrack(track));

   441

	assert(GetRailTileType(tile) == RAIL_TYPE_SIGNALS);

   443

}

   444

   445

/**

   446

 * Checks if this tile contains semaphores (returns true) or normal signals

   447

 * (returns false) on the given track. Does not check if there are actually

   448

 * signals on the track, you should use HasSignalsOnTrack() for that.

   449

 *

   450

 * Note that currently, the track argument is not used, since

   451

 * semaphores/electric signals cannot be mixed. This function is trying to be

   452

 * future-compatible, though.

   453

 */

   454

static inline bool HasSemaphores(TileIndex tile, Track track)

   455

{

   456

	assert(IsValidTrack(track));

   458

}

   459

   460

/**

   461

 * Return the rail type of tile, or INVALID_RAILTYPE if this is no rail tile.

   462

 * Note that there is no check if the given trackdir is actually present on

   463

 * the tile!

   464

 * The given trackdir is used when there are (could be) multiple rail types on

   465

 * one tile.

   466

 */

   467

RailType GetTileRailType(TileIndex tile, Trackdir trackdir);

   468

   469

/**

   470

 * Returns whether the given tile is a level crossing.

   471

 */

   472

static inline bool IsLevelCrossing(TileIndex tile)

   473

{

   475

}

   476

   477

/**

   478

 * Gets the transport type of the given track on the given crossing tile.

   479

 * @return  The transport type of the given track, either TRANSPORT_ROAD,

   480

 * TRANSPORT_RAIL.

   481

 */

   482

static inline TransportType GetCrossingTransportType(TileIndex tile, Track track)

   483

{

   484

	/* XXX: Nicer way to write this? */

   485

	switch(track)

   486

	{

   487

		/* When map5 bit 3 is set, the road runs in the y direction (DIAG2) */

   488

		case TRACK_DIAG1:

   490

		case TRACK_DIAG2:

   492

		default:

   493

			assert(0);

   494

	}

   495

	return INVALID_TRANSPORT;

   496

}

   497

   498

/**

   499

 * Checks if an engine of the given RailType can drive on a tile with a given

   500

 * RailType. This would normally just be an equality check, but for electric

   501

 * rails (which also support non-electric engines).

   502

 * @return Whether the engine can drive on this tile.

   503

 * @param  enginetype The RailType of the engine we are considering.

   504

 * @param  tiletype   The RailType of the tile we are considering.

   505

 */

   506

static inline bool IsCompatibleRail(RailType enginetype, RailType tiletype)

   507

{

   508

	static const bool EquivRailTypes[RAILTYPE_END][RAILTYPE_END] = {

   509

	{ true, false, false },

   510

	{ false, true, false },