1

/* $Id$ */

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#include "stdafx.h"

     4

#include "openttd.h"

     5

#include "debug.h"

     6

#include "functions.h"

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#include "npf.h"

     8

#include "aystar.h"

     9

#include "macros.h"

    10

#include "pathfind.h"

    11

#include "station.h"

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#include "tile.h"

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#include "depot.h"

    14

    15

static AyStar _npf_aystar;

    16

    17

/* The cost of each trackdir. A diagonal piece is the full NPF_TILE_LENGTH,

    18

 * the shorter piece is sqrt(2)/2*NPF_TILE_LENGTH =~ 0.7071

    19

 */

    20

#define NPF_STRAIGHT_LENGTH (uint)(NPF_TILE_LENGTH * STRAIGHT_TRACK_LENGTH)

    21

static const uint _trackdir_length[TRACKDIR_END] = {

    22

	NPF_TILE_LENGTH, NPF_TILE_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH,

    23

	0, 0,

    24

	NPF_TILE_LENGTH, NPF_TILE_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH

    25

};

    26

    27

/**

    28

 * Calculates the minimum distance traveled to get from t0 to t1 when only

    29

 * using tracks (ie, only making 45 degree turns). Returns the distance in the

    30

 * NPF scale, ie the number of full tiles multiplied by NPF_TILE_LENGTH to

    31

 * prevent rounding.

    32

 */

    33

static uint NPFDistanceTrack(TileIndex t0, TileIndex t1)

    34

{

    35

	const uint dx = abs(TileX(t0) - TileX(t1));

    36

	const uint dy = abs(TileY(t0) - TileY(t1));

    37

    38

	const uint straightTracks = 2 * min(dx, dy); /* The number of straight (not full length) tracks */

    39

	/* OPTIMISATION:

    40

	 * Original: diagTracks = max(dx, dy) - min(dx,dy);

    41

	 * Proof:

    42

	 * (dx+dy) - straightTracks  == (min + max) - straightTracks = min + max - 2 * min = max - min */

    43

	const uint diagTracks = dx + dy - straightTracks; /* The number of diagonal (full tile length) tracks. */

    44

    45

	/* Don't factor out NPF_TILE_LENGTH below, this will round values and lose

    46

	 * precision */

    47

	return diagTracks * NPF_TILE_LENGTH + straightTracks * NPF_TILE_LENGTH * STRAIGHT_TRACK_LENGTH;

    48

}

    49

    50

    51

#if 0

    52

static uint NTPHash(uint key1, uint key2)

    53

{

    54

	/* This function uses the old hash, which is fixed on 10 bits (1024 buckets) */

    55

	return PATHFIND_HASH_TILE(key1);

    56

}

    57

#endif

    58

    59

/**

    60

 * Calculates a hash value for use in the NPF.

    61

 * @param key1	The TileIndex of the tile to hash

    62

 * @param key1	The Trackdir of the track on the tile.

    63

 *

    64

 * @todo	Think of a better hash.

    65

 */

    66

static uint NPFHash(uint key1, uint key2)

    67

{

    68

	/* TODO: think of a better hash? */

    69

	uint part1 = TileX(key1) & NPF_HASH_HALFMASK;

    70

	uint part2 = TileY(key1) & NPF_HASH_HALFMASK;

    71

    72

	assert(IsValidTrackdir(key2));

    73

	assert(IsValidTile(key1));

    74

	return ((part1 << NPF_HASH_HALFBITS | part2) + (NPF_HASH_SIZE * key2 / TRACKDIR_END)) % NPF_HASH_SIZE;

    75

}

    76

    77

static int32 NPFCalcZero(AyStar* as, AyStarNode* current, OpenListNode* parent)

    78

{

    79

	return 0;

    80

}

    81

    82

/* Calcs the tile of given station that is closest to a given tile

    83

 * for this we assume the station is a rectangle,

    84

 * as defined by its top tile (st->train_tile) and its width/height (st->trainst_w, st->trainst_h)

    85

 */

    86

static TileIndex CalcClosestStationTile(StationID station, TileIndex tile)

    87

{

    88

	const Station* st = GetStation(station);

    89

    90

	uint minx = TileX(st->train_tile);  // topmost corner of station

    91

	uint miny = TileY(st->train_tile);

    92

	uint maxx = minx + st->trainst_w - 1; // lowermost corner of station

    93

	uint maxy = miny + st->trainst_h - 1;

    94

	uint x;

    95

	uint y;

    96

    97

	// we are going the aim for the x coordinate of the closest corner

    98

	// but if we are between those coordinates, we will aim for our own x coordinate

    99

	x = clamp(TileX(tile), minx, maxx);

   100

   101

	// same for y coordinate, see above comment

   102

	y = clamp(TileY(tile), miny, maxy);

   103

   104

	// return the tile of our target coordinates

   105

	return TileXY(x, y);

   106

}

   107

   108

/* Calcs the heuristic to the target station or tile. For train stations, it

   109

 * takes into account the direction of approach.

   110

 */

   111

static int32 NPFCalcStationOrTileHeuristic(AyStar* as, AyStarNode* current, OpenListNode* parent)

   112

{

   113

	NPFFindStationOrTileData* fstd = (NPFFindStationOrTileData*)as->user_target;

   114

	NPFFoundTargetData* ftd = (NPFFoundTargetData*)as->user_path;

   115

	TileIndex from = current->tile;

   116

	TileIndex to = fstd->dest_coords;

   117

	uint dist;

   118

   119

	// for train-stations, we are going to aim for the closest station tile

   120

	if (as->user_data[NPF_TYPE] == TRANSPORT_RAIL && fstd->station_index != -1)

   121

		to = CalcClosestStationTile(fstd->station_index, from);

   122

   123

	if (as->user_data[NPF_TYPE] == TRANSPORT_ROAD) {

   124

		/* Since roads only have diagonal pieces, we use manhattan distance here */

   125

		dist = DistanceManhattan(from, to) * NPF_TILE_LENGTH;

   126

	} else {

   127

		/* Ships and trains can also go diagonal, so the minimum distance is shorter */

   128

		dist = NPFDistanceTrack(from, to);

   129

	}

   130

   131

	DEBUG(npf, 4)("Calculating H for: (%d, %d). Result: %d", TileX(current->tile), TileY(current->tile), dist);

   132

   133

	if (dist < ftd->best_bird_dist) {

   134

		ftd->best_bird_dist = dist;

   135

		ftd->best_trackdir = current->user_data[NPF_TRACKDIR_CHOICE];

   136

	}

   137

	return dist;

   138

}

   139

   140

   141

/* Fills AyStarNode.user_data[NPF_TRACKDIRCHOICE] with the chosen direction to

   142

 * get here, either getting it from the current choice or from the parent's

   143

 * choice */

   144

static void NPFFillTrackdirChoice(AyStarNode* current, OpenListNode* parent)

   145

{

   146

	if (parent->path.parent == NULL) {

   147

		Trackdir trackdir = (Trackdir)current->direction;

   148

		/* This is a first order decision, so we'd better save the

   149

		 * direction we chose */

   150

		current->user_data[NPF_TRACKDIR_CHOICE] = trackdir;

   151

		DEBUG(npf, 6)("Saving trackdir: %#x", trackdir);

   152

	} else {

   153

		/* We've already made the decision, so just save our parent's decision */

   154

		current->user_data[NPF_TRACKDIR_CHOICE] = parent->path.node.user_data[NPF_TRACKDIR_CHOICE];

   155

	}

   156

}

   157

   158

/* Will return the cost of the tunnel. If it is an entry, it will return the

   159

 * cost of that tile. If the tile is an exit, it will return the tunnel length

   160

 * including the exit tile. Requires that this is a Tunnel tile */

   161

static uint NPFTunnelCost(AyStarNode* current)

   162

{

   163

	DiagDirection exitdir = TrackdirToExitdir((Trackdir)current->direction);

   164

	TileIndex tile = current->tile;

   165

	if ((DiagDirection)GB(_m[tile].m5, 0, 2) == ReverseDiagdir(exitdir)) {

   166

		/* We just popped out if this tunnel, since were

   167

		 * facing the tunnel exit */

   168

		FindLengthOfTunnelResult flotr;

   169

		flotr = FindLengthOfTunnel(tile, ReverseDiagdir(exitdir));

   170

		return flotr.length * NPF_TILE_LENGTH;

   171

		//TODO: Penalty for tunnels?

   172

	} else {

   173

		/* We are entering the tunnel, the enter tile is just a

   174

		 * straight track */

   175

		return NPF_TILE_LENGTH;

   176

	}

   177

}

   178

   179

static uint NPFSlopeCost(AyStarNode* current)

   180

{

   181

	TileIndex next = current->tile + TileOffsByDir(TrackdirToExitdir(current->direction));

   182

	int x,y;

   183

	int8 z1,z2;

   184

   185

	x = TileX(current->tile) * TILE_SIZE;

   186

	y = TileY(current->tile) * TILE_SIZE;

   187

	/* get the height of the center of the current tile */

   188

	z1 = GetSlopeZ(x+TILE_HEIGHT, y+TILE_HEIGHT);

   189

   190

	x = TileX(next) * TILE_SIZE;

   191

	y = TileY(next) * TILE_SIZE;

   192

	/* get the height of the center of the next tile */

   193

	z2 = GetSlopeZ(x+TILE_HEIGHT, y+TILE_HEIGHT);

   194

   195

	if (z2 - z1 > 1) {

   196

		/* Slope up */

   197

		return _patches.npf_rail_slope_penalty;

   198

	}

   199

	return 0;

   200

	/* Should we give a bonus for slope down? Probably not, we

   201

	 * could just substract that bonus from the penalty, because

   202

	 * there is only one level of steepness... */

   203

}

   204

   205

/* Mark tiles by mowing the grass when npf debug level >= 1 */

   206

static void NPFMarkTile(TileIndex tile)

   207

{

   208

#ifdef NO_DEBUG_MESSAGES

   209

	return;

   210

#else

   211

	if (_debug_npf_level >= 1)

   213

			case MP_RAILWAY:

   214

				/* DEBUG: mark visited tiles by mowing the grass under them

   215

				 * ;-) */

   216

				if (!IsTileDepotType(tile, TRANSPORT_RAIL)) {

   217

					SB(_m[tile].m2, 0, 4, 0);

   218

					MarkTileDirtyByTile(tile);

   219

				}

   220

				break;

   221

			case MP_STREET:

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				if (!IsTileDepotType(tile, TRANSPORT_ROAD)) {

   223

					SB(_m[tile].m4, 4, 3, 0);

   224

					MarkTileDirtyByTile(tile);

   225

				}

   226

				break;

   227

			default:

   228

				break;

   229

		}

   230

#endif

   231

}

   232

   233

static int32 NPFWaterPathCost(AyStar* as, AyStarNode* current, OpenListNode* parent)

   234

{

   235

	//TileIndex tile = current->tile;

   236

	int32 cost = 0;

   237

	Trackdir trackdir = (Trackdir)current->direction;

   238

   239

	cost = _trackdir_length[trackdir]; /* Should be different for diagonal tracks */

   240

   241

	if (IsBuoyTile(current->tile) && IsDiagonalTrackdir(trackdir))

   242

		cost += _patches.npf_buoy_penalty; /* A small penalty for going over buoys */

   243

   244

	if (current->direction != NextTrackdir((Trackdir)parent->path.node.direction))

   245

		cost += _patches.npf_water_curve_penalty;

   246

   247

	/* TODO More penalties? */

   248

   249

	return cost;

   250

}

   251

   252

/* Determine the cost of this node, for road tracks */

   253

static int32 NPFRoadPathCost(AyStar* as, AyStarNode* current, OpenListNode* parent)

   254

{

   255

	TileIndex tile = current->tile;

   256

	int32 cost = 0;

   257

   258

	/* Determine base length */

   259

	switch (GetTileType(tile)) {

   260

		case MP_TUNNELBRIDGE:

   261

			if (GB(_m[tile].m5, 4, 4) == 0) {

   262

				cost = NPFTunnelCost(current);

   263

				break;

   264

			}

   265

			cost = NPF_TILE_LENGTH;

   266

			break;

   267

   268

		case MP_STREET:

   269

			cost = NPF_TILE_LENGTH;

   270

			/* Increase the cost for level crossings */

   271

			if (IsLevelCrossing(tile))

   272

				cost += _patches.npf_crossing_penalty;

   273

			break;

   274

   275

		default:

   276

			break;

   277

	}

   278

   279

	/* Determine extra costs */

   280

   281

	/* Check for slope */

   282

	cost += NPFSlopeCost(current);

   283

   284

	/* Check for turns. Road vehicles only really drive diagonal, turns are

   285

	 * represented by non-diagonal tracks */

   286

	if (!IsDiagonalTrackdir(current->direction))

   287

		cost += _patches.npf_road_curve_penalty;

   288

   289

	NPFMarkTile(tile);

   290

	DEBUG(npf, 4)("Calculating G for: (%d, %d). Result: %d", TileX(current->tile), TileY(current->tile), cost);

   291

	return cost;

   292

}

   293

   294

   295

/* Determine the cost of this node, for railway tracks */

   296

static int32 NPFRailPathCost(AyStar* as, AyStarNode* current, OpenListNode* parent)

   297

{

   298

	TileIndex tile = current->tile;

   299

	Trackdir trackdir = (Trackdir)current->direction;

   300

	int32 cost = 0;

   301

	/* HACK: We create a OpenListNode manualy, so we can call EndNodeCheck */

   302

	OpenListNode new_node;

   303

   304

	/* Determine base length */

   305

	switch (GetTileType(tile)) {

   306

		case MP_TUNNELBRIDGE:

   307

			if (GB(_m[tile].m5, 4, 4) == 0) {

   308

				cost = NPFTunnelCost(current);

   309

				break;

   310

			}

   311

			/* Fall through if above if is false, it is a bridge

   312

			 * then. We treat that as ordinary rail */

   313

   314

		case MP_RAILWAY:

   315

			cost = _trackdir_length[trackdir]; /* Should be different for diagonal tracks */

   316

			break;

   317

   318

		case MP_STREET: /* Railway crossing */

   319

			cost = NPF_TILE_LENGTH;

   320

			break;

   321

   322

		case MP_STATION:

   323

			/* We give a station tile a penalty. Logically we would only want to give

   324

			 * station tiles that are not our destination this penalty. This would

   325

			 * discourage trains to drive through busy stations. But, we can just

   326

			 * give any station tile a penalty, because every possible route will get

   327

			 * this penalty exactly once, on its end tile (if it's a station) and it

   328

			 * will therefore not make a difference. */

   329

			cost = NPF_TILE_LENGTH + _patches.npf_rail_station_penalty;

   330

			break;

   331

   332

		default:

   333

			break;

   334

	}

   335

   336

	/* Determine extra costs */

   337

   338

	/* Check for signals */

   339

	if (IsTileType(tile, MP_RAILWAY) && HasSignalOnTrackdir(tile, trackdir)) {

   340

		/* Ordinary track with signals */

   341

		if (GetSignalState(tile, trackdir) == SIGNAL_STATE_RED) {

   342

			/* Signal facing us is red */

   343

			if (!NPFGetFlag(current, NPF_FLAG_SEEN_SIGNAL)) {

   344

				/* Penalize the first signal we

   345

				 * encounter, if it is red */

   346

   347

				/* Is this a presignal exit or combo? */

   348

				SignalType sigtype = GetSignalType(tile, TrackdirToTrack(trackdir));

   349

				if (sigtype == SIGTYPE_EXIT || sigtype == SIGTYPE_COMBO) {

   350

					/* Penalise exit and combo signals differently (heavier) */

   351

					cost += _patches.npf_rail_firstred_exit_penalty;

   352

				} else {

   353

					cost += _patches.npf_rail_firstred_penalty;

   354

				}

   355

			}

   356

			/* Record the state of this signal */

   357

			NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, true);

   358

		} else {

   359

			/* Record the state of this signal */

   360

			NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, false);

   361

		}

   362

		NPFSetFlag(current, NPF_FLAG_SEEN_SIGNAL, true);

   363

	}

   364

   365

	/* Penalise the tile if it is a target tile and the last signal was

   366

	 * red */

   367

	/* HACK: We create a new_node here so we can call EndNodeCheck. Ugly as hell

   368

	 * of course... */

   369

	new_node.path.node = *current;

   370

	if (as->EndNodeCheck(as, &new_node) == AYSTAR_FOUND_END_NODE && NPFGetFlag(current, NPF_FLAG_LAST_SIGNAL_RED))

   371

		cost += _patches.npf_rail_lastred_penalty;

   372

   373

	/* Check for slope */

   374

	cost += NPFSlopeCost(current);

   375

   376

	/* Check for turns */

   377

	if (current->direction != NextTrackdir((Trackdir)parent->path.node.direction))

   378

		cost += _patches.npf_rail_curve_penalty;

   379

	//TODO, with realistic acceleration, also the amount of straight track between

   380

	//      curves should be taken into account, as this affects the speed limit.

   381

   382

	/* Check for reverse in depot */

   383

	if (IsTileDepotType(tile, TRANSPORT_RAIL) && as->EndNodeCheck(as, &new_node) != AYSTAR_FOUND_END_NODE) {

   384

		/* Penalise any depot tile that is not the last tile in the path. This

   385

		 * _should_ penalise every occurence of reversing in a depot (and only

   386

		 * that) */

   387

		cost += _patches.npf_rail_depot_reverse_penalty;

   388

	}

   389

   390

	/* Check for occupied track */

   391

	//TODO

   392

   393

	NPFMarkTile(tile);

   394

	DEBUG(npf, 4)("Calculating G for: (%d, %d). Result: %d", TileX(current->tile), TileY(current->tile), cost);

   395

	return cost;

   396

}

   397

   398

/* Will find any depot */

   399

static int32 NPFFindDepot(AyStar* as, OpenListNode *current)

   400

{

   401

	TileIndex tile = current->path.node.tile;

   402

   403

	/* It's not worth caching the result with NPF_FLAG_IS_TARGET here as below,

   404

	 * since checking the cache not that much faster than the actual check */

   405

	if (IsTileDepotType(tile, as->user_data[NPF_TYPE])) {

   406

		return AYSTAR_FOUND_END_NODE;

   407

	} else {

   408

		return AYSTAR_DONE;

   409

	}

   410

}

   411

   412

/* Will find a station identified using the NPFFindStationOrTileData */

   413

static int32 NPFFindStationOrTile(AyStar* as, OpenListNode *current)

   414

{

   415

	NPFFindStationOrTileData* fstd = (NPFFindStationOrTileData*)as->user_target;

   416

	AyStarNode *node = &current->path.node;

   417

	TileIndex tile = node->tile;

   418

   419

	/* If GetNeighbours said we could get here, we assume the station type

   420

	 * is correct */

   421

	if (

   422

		(fstd->station_index == -1 && tile == fstd->dest_coords) || /* We've found the tile, or */

   423

		(IsTileType(tile, MP_STATION) && _m[tile].m2 == fstd->station_index) /* the station */

   424

	) {

   425

		return AYSTAR_FOUND_END_NODE;

   426

	} else {

   427

		return AYSTAR_DONE;

   428

	}

   429

}

   430

   431

/* To be called when current contains the (shortest route to) the target node.

   432

 * Will fill the contents of the NPFFoundTargetData using

   433

 * AyStarNode[NPF_TRACKDIR_CHOICE].

   434

 */

   435

static void NPFSaveTargetData(AyStar* as, OpenListNode* current)

   436

{

   437

	NPFFoundTargetData* ftd = (NPFFoundTargetData*)as->user_path;

   438

	ftd->best_trackdir = (Trackdir)current->path.node.user_data[NPF_TRACKDIR_CHOICE];

   439

	ftd->best_path_dist = current->g;

   440

	ftd->best_bird_dist = 0;

   441

	ftd->node = current->path.node;

   442

}

   443

   444

/**

   445

 * Finds out if a given player's vehicles are allowed to enter a given tile.

   446

 * @param owner    The owner of the vehicle.

   447

 * @param tile     The tile that is about to be entered.

   448

 * @param enterdir The direction from which the vehicle wants to enter the tile.

   449

 * @return         true if the vehicle can enter the tile.

   450

 * @todo           This function should be used in other places than just NPF,

   451

 *                 maybe moved to another file too.

   452

 */

   453

static bool VehicleMayEnterTile(Owner owner, TileIndex tile, DiagDirection enterdir)

   454

{

   455

	if (IsTileType(tile, MP_RAILWAY) ||           /* Rail tile (also rail depot) */

   456

			IsTrainStationTile(tile) ||               /* Rail station tile */

   457

			IsTileDepotType(tile, TRANSPORT_ROAD) ||  /* Road depot tile */

   458

			IsRoadStationTile(tile) ||                /* Road station tile */

   459

			IsTileDepotType(tile, TRANSPORT_WATER)) { /* Water depot tile */

   460

		return IsTileOwner(tile, owner); /* You need to own these tiles entirely to use them */

   461

	}

   462

   463

	switch (GetTileType(tile)) {

   464

		case MP_STREET:

   465

			/* rail-road crossing : are we looking at the railway part? */

   466

			if (IsLevelCrossing(tile) && GetCrossingTransportType(tile, TrackdirToTrack(DiagdirToDiagTrackdir(enterdir))) == TRANSPORT_RAIL)

   467

				return IsTileOwner(tile, owner); /* Railway needs owner check, while the street is public */

   468

			break;

   469

   470

		case MP_TUNNELBRIDGE:

   471

#if 0

   472

/* OPTIMISATION: If we are on the middle of a bridge, we will not do the cpu

   473

 * intensive owner check, instead we will just assume that if the vehicle

   474

 * managed to get on the bridge, it is probably allowed to :-)

   475

 */

   476

			if ((_m[tile].m5 & 0xC6) == 0xC0 && GB(_m[tile].m5, 0, 1) == (enterdir & 0x1)) {

   477

				/* on the middle part of a railway bridge: find bridge ending */

   478

				while (IsTileType(tile, MP_TUNNELBRIDGE) && !((_m[tile].m5 & 0xC6) == 0x80)) {

   479

					tile += TileOffsByDir(GB(_m[tile].m5, 0, 1));

   480

				}

   481

			}

   482

			/* if we were on a railway middle part, we are now at a railway bridge ending */

   483

#endif

   484

			if ((_m[tile].m5 & 0xFC) == 0 || /* railway tunnel */

   485

					(_m[tile].m5 & 0xC6) == 0x80 || /* railway bridge ending */

   486

					((_m[tile].m5 & 0xF8) == 0xE0 && GB(_m[tile].m5, 0, 1) != (enterdir & 0x1))) { /* railway under bridge */

   487

				return IsTileOwner(tile, owner);

   488

			}

   489

			break;

   490

   491

		default:

   492

			break;