1

/* $Id$ */

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     3

#include "stdafx.h"

     4

#include "openttd.h"

     5

#include "bridge_map.h"

     6

#include "debug.h"

     7

#include "functions.h"

     8

#include "npf.h"

     9

#include "aystar.h"

    10

#include "macros.h"

    11

#include "pathfind.h"

    12

#include "station.h"

    13

#include "station_map.h"

    14

#include "tile.h"

    15

#include "depot.h"

    16

#include "tunnel_map.h"

    17

#include "network.h"

    18

#include "water_map.h"

    19

    20

static AyStar _npf_aystar;

    21

    22

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

    23

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

    24

 */

    25

#define NPF_STRAIGHT_LENGTH (uint)(NPF_TILE_LENGTH * STRAIGHT_TRACK_LENGTH)

    26

static const uint _trackdir_length[TRACKDIR_END] = {

    27

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

    28

	0, 0,

    29

	NPF_TILE_LENGTH, NPF_TILE_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH

    30

};

    31

    32

/**

    33

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

    34

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

    35

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

    36

 * prevent rounding.

    37

 */

    38

static uint NPFDistanceTrack(TileIndex t0, TileIndex t1)

    39

{

    40

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

    41

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

    42

    43

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

    44

	/* OPTIMISATION:

    45

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

    46

	 * Proof:

    47

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

    48

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

    49

    50

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

    51

	 * precision */

    52

	return diagTracks * NPF_TILE_LENGTH + straightTracks * NPF_TILE_LENGTH * STRAIGHT_TRACK_LENGTH;

    53

}

    54

    55

    56

#if 0

    57

static uint NTPHash(uint key1, uint key2)

    58

{

    59

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

    60

	return PATHFIND_HASH_TILE(key1);

    61

}

    62

#endif

    63

    64

/**

    65

 * Calculates a hash value for use in the NPF.

    66

 * @param key1	The TileIndex of the tile to hash

    67

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

    68

 *

    69

 * @todo	Think of a better hash.

    70

 */

    71

static uint NPFHash(uint key1, uint key2)

    72

{

    73

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

    74

	uint part1 = TileX(key1) & NPF_HASH_HALFMASK;

    75

	uint part2 = TileY(key1) & NPF_HASH_HALFMASK;

    76

    77

	assert(IsValidTrackdir(key2));

    78

	assert(IsValidTile(key1));

    79

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

    80

}

    81

    82

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

    83

{

    84

	return 0;

    85

}

    86

    87

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

    88

 * for this we assume the station is a rectangle,

    89

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

    90

 */

    91

static TileIndex CalcClosestStationTile(StationID station, TileIndex tile)

    92

{

    93

	const Station* st = GetStation(station);

    94

    95

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

    96

	uint miny = TileY(st->train_tile);

    97

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

    98

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

    99

	uint x;

   100

	uint y;

   101

   102

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

   103

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

   104

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

   105

   106

	// same for y coordinate, see above comment

   107

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

   108

   109

	// return the tile of our target coordinates

   110

	return TileXY(x, y);

   111

}

   112

   113

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

   114

 * takes into account the direction of approach.

   115

 */

   116

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

   117

{

   118

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

   119

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

   120

	TileIndex from = current->tile;

   121

	TileIndex to = fstd->dest_coords;

   122

	uint dist;

   123

   124

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

   125

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

   126

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

   127

   128

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

   129

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

   130

		dist = DistanceManhattan(from, to) * NPF_TILE_LENGTH;

   131

	} else {

   132

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

   133

		dist = NPFDistanceTrack(from, to);

   134

	}

   135

   136

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

   137

   138

	if (dist < ftd->best_bird_dist) {

   139

		ftd->best_bird_dist = dist;

   140

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

   141

	}

   142

	return dist;

   143

}

   144

   145

   146

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

   147

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

   148

 * choice */

   149

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

   150

{

   151

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

   152

		Trackdir trackdir = (Trackdir)current->direction;

   153

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

   154

		 * direction we chose */

   155

		current->user_data[NPF_TRACKDIR_CHOICE] = trackdir;

   156

		DEBUG(npf, 6)("Saving trackdir: 0x%X", trackdir);

   157

	} else {

   158

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

   159

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

   160

	}

   161

}

   162

   163

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

   164

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

   165

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

   166

static uint NPFTunnelCost(AyStarNode* current)

   167

{

   168

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

   169

	TileIndex tile = current->tile;

   170

	if (GetTunnelDirection(tile) == ReverseDiagDir(exitdir)) {

   171

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

   172

		 * facing the tunnel exit */

   173

		FindLengthOfTunnelResult flotr;

   174

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

   175

		return flotr.length * NPF_TILE_LENGTH;

   176

		//TODO: Penalty for tunnels?

   177

	} else {

   178

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

   179

		 * straight track */

   180

		return NPF_TILE_LENGTH;

   181

	}

   182

}

   183

   184

static uint NPFSlopeCost(AyStarNode* current)

   185

{

   186

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

   187

	int x,y;

   188

	int8 z1,z2;

   189

   190

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

   191

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

   192

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

   193

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

   194

   195

	x = TileX(next) * TILE_SIZE;

   196

	y = TileY(next) * TILE_SIZE;

   197

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

   198

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

   199

   200

	if (z2 - z1 > 1) {

   201

		/* Slope up */

   202

		return _patches.npf_rail_slope_penalty;

   203

	}

   204

	return 0;

   205

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

   206

	 * could just substract that bonus from the penalty, because

   207

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

   208

}

   209

   210

/**

   211

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

   212

 * Will not work for multiplayer games, since it can (will) cause desyncs.

   213

 */

   214

static void NPFMarkTile(TileIndex tile)

   215

{

   216

#ifdef NO_DEBUG_MESSAGES

   217

	return;

   218

#else

   219

	if (_debug_npf_level < 1 || _networking) return;

   220

	switch (GetTileType(tile)) {

   221

		case MP_RAILWAY:

   222

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

   223

			if (!IsTileDepotType(tile, TRANSPORT_RAIL)) {

   224

				SetRailGroundType(tile, RAIL_GROUND_BARREN);

   225

				MarkTileDirtyByTile(tile);

   226

			}

   227

			break;

   228

   229

		case MP_STREET:

   230

			if (!IsTileDepotType(tile, TRANSPORT_ROAD)) {

   231

				SetGroundType(tile, RGT_BARREN);

   232

				MarkTileDirtyByTile(tile);

   233

			}

   234

			break;

   235

   236

		default:

   237

			break;

   238

	}

   239

#endif

   240

}

   241

   242

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

   243

{

   244

	//TileIndex tile = current->tile;

   245

	int32 cost = 0;

   246

	Trackdir trackdir = (Trackdir)current->direction;

   247

   248

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

   249

   250

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

   251

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

   252

   253

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

   254

		cost += _patches.npf_water_curve_penalty;

   255

   256

	/* TODO More penalties? */

   257

   258

	return cost;

   259

}

   260

   261

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

   262

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

   263

{

   264

	TileIndex tile = current->tile;

   265

	int32 cost = 0;

   266

   267

	/* Determine base length */

   268

	switch (GetTileType(tile)) {

   269

		case MP_TUNNELBRIDGE:

   270

			if (IsTunnel(tile)) {

   271

				cost = NPFTunnelCost(current);

   272

			} else {

   273

				cost = NPF_TILE_LENGTH;

   274

			}

   275

			break;

   276

   277

		case MP_STREET:

   278

			cost = NPF_TILE_LENGTH;

   279

			/* Increase the cost for level crossings */

   280

			if (IsLevelCrossing(tile))

   281

				cost += _patches.npf_crossing_penalty;

   282

			break;

   283

   284

		default:

   285

			break;

   286

	}

   287

   288

	/* Determine extra costs */

   289

   290

	/* Check for slope */

   291

	cost += NPFSlopeCost(current);

   292

   293

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

   294

	 * represented by non-diagonal tracks */

   295

	if (!IsDiagonalTrackdir(current->direction))

   296

		cost += _patches.npf_road_curve_penalty;

   297

   298

	NPFMarkTile(tile);

   299

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

   300

	return cost;

   301

}

   302

   303

   304

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

   305

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

   306

{

   307

	TileIndex tile = current->tile;

   308

	Trackdir trackdir = (Trackdir)current->direction;

   309

	int32 cost = 0;

   310

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

   311

	OpenListNode new_node;

   312

   313

	/* Determine base length */

   314

	switch (GetTileType(tile)) {

   315

		case MP_TUNNELBRIDGE:

   316

			if (IsTunnel(tile)) {

   317

				cost = NPFTunnelCost(current);

   318

				break;

   319

			}

   320

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

   321

			 * then. We treat that as ordinary rail */

   322

   323

		case MP_RAILWAY:

   324

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

   325

			break;

   326

   327

		case MP_STREET: /* Railway crossing */

   328

			cost = NPF_TILE_LENGTH;

   329

			break;

   330

   331

		case MP_STATION:

   332

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

   333

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

   334

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

   335

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

   336

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

   337

			 * will therefore not make a difference. */

   338

			cost = NPF_TILE_LENGTH + _patches.npf_rail_station_penalty;

   339

			break;

   340

   341

		default:

   342

			break;

   343

	}

   344

   345

	/* Determine extra costs */

   346

   347

	/* Check for signals */

   348

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

   349

		/* Ordinary track with signals */

   350

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

   351

			/* Signal facing us is red */

   352

			if (!NPFGetFlag(current, NPF_FLAG_SEEN_SIGNAL)) {

   353

				/* Penalize the first signal we

   354

				 * encounter, if it is red */

   355

   356

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

   357

				SignalType sigtype = GetSignalType(tile);

   358

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

   359

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

   360

					cost += _patches.npf_rail_firstred_exit_penalty;

   361

				} else {

   362

					cost += _patches.npf_rail_firstred_penalty;

   363

				}

   364

			}

   365

			/* Record the state of this signal */

   366

			NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, true);

   367

		} else {

   368

			/* Record the state of this signal */

   369

			NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, false);

   370

		}

   371

		NPFSetFlag(current, NPF_FLAG_SEEN_SIGNAL, true);

   372

	}

   373

   374

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

   375

	 * red */

   376

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

   377

	 * of course... */

   378

	new_node.path.node = *current;

   379

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

   380

		cost += _patches.npf_rail_lastred_penalty;

   381

   382

	/* Check for slope */

   383

	cost += NPFSlopeCost(current);

   384

   385

	/* Check for turns */

   386

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

   387

		cost += _patches.npf_rail_curve_penalty;

   388

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

   389

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

   390

   391

	/* Check for reverse in depot */

   392

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

   393

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

   394

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

   395

		 * that) */

   396

		cost += _patches.npf_rail_depot_reverse_penalty;

   397

	}

   398

   399

	/* Check for occupied track */

   400

	//TODO

   401

   402

	NPFMarkTile(tile);

   403

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

   404

	return cost;

   405

}

   406

   407

/* Will find any depot */

   408

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

   409

{

   410

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

   411

   412

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

   413

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

   414

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

   415

		return AYSTAR_FOUND_END_NODE;

   416

	} else {

   417

		return AYSTAR_DONE;

   418

	}

   419

}

   420

   421

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

   422

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

   423

{

   424

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

   425

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

   426

	TileIndex tile = node->tile;

   427

   428

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

   429

	 * is correct */

   430

	if (

   431

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

   432

		(IsTileType(tile, MP_STATION) && GetStationIndex(tile) == fstd->station_index) /* the station */

   433

	) {

   434

		return AYSTAR_FOUND_END_NODE;

   435

	} else {

   436

		return AYSTAR_DONE;

   437

	}

   438

}

   439

   440

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

   441

 * Will fill the contents of the NPFFoundTargetData using

   442

 * AyStarNode[NPF_TRACKDIR_CHOICE].

   443

 */

   444

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

   445

{

   446

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

   447

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

   448

	ftd->best_path_dist = current->g;

   449

	ftd->best_bird_dist = 0;

   450

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

   451

}

   452

   453

/**

   454

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

   455

 * @param owner    The owner of the vehicle.

   456

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

   457

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

   458

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

   459

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

   460

 *                 maybe moved to another file too.

   461

 */

   462

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

   463

{

   464

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

   465

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

   466

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

   467

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

   468

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

   469

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

   470

	}

   471

   472

	switch (GetTileType(tile)) {

   473

		case MP_STREET:

   474

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

   475

			if (IsLevelCrossing(tile) &&

   476

					DiagDirToAxis(enterdir) != GetCrossingRoadAxis(tile)) {

   477

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

   478

			}

   479

			break;

   480

   481

		case MP_TUNNELBRIDGE:

   482

			if ((IsTunnel(tile) && GetTunnelTransportType(tile) == TRANSPORT_RAIL) ||

   483

					(IsBridge(tile) && GetBridgeTransportType(tile) == TRANSPORT_RAIL)) {

   484

				return IsTileOwner(tile, owner);

   485

			}

   486

			break;

   487

   488

		default:

   489

			break;

   490

	}

   491