1

#include "stdafx.h"

     2

#include "ttd.h"

     3

#include "debug.h"

     4

#include "npf.h"

     5

#include "aystar.h"

     6

#include "macros.h"

     7

#include "pathfind.h"

     8

#include "station.h"

     9

#include "tile.h"

    10

#include "depot.h"

    11

    12

AyStar _train_find_station;

    13

AyStar _train_find_depot;

    14

AyStar _road_find_station;

    15

AyStar _road_find_depot;

    16

AyStar _npf_aystar;

    17

    18

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

    19

 * direction along with the trackdir */

    20

const byte _signal_along_trackdir[14] = {

    21

	0x80, 0x80, 0x80, 0x20, 0x40, 0x10, 0, 0,

    22

	0x40, 0x40, 0x40, 0x10, 0x80, 0x20

    23

};

    24

    25

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

    26

 * direction against the trackdir */

    27

const byte _signal_against_trackdir[14] = {

    28

	0x40, 0x40, 0x40, 0x10, 0x80, 0x20, 0, 0,

    29

	0x80, 0x80, 0x80, 0x20, 0x40, 0x10

    30

};

    31

    32

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

    33

 * entering the next tile */

    34

const uint16 _trackdir_reaches_trackdirs[14] = {

    35

0x1009, 0x0016, 0x1009, 0x0016, 0x0520, 0x0016, 0, 0,

    36

0x0520, 0x2A00, 0x2A00, 0x0520, 0x2A00, 0x1009

    37

};

    38

    39

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

    40

const uint16 _trackdir_crosses_trackdirs[14] = {

    41

0x0202, 0x0101, 0x3030, 0x3030, 0x0C0C, 0x0C0C, 0, 0,

    42

0x0202, 0x0101, 0x3030, 0x3030, 0x0C0C, 0x0C0C

    43

};

    44

    45

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

    46

const byte _track_crosses_tracks[6] = {

    47

	0x2, /* Track 1 -> Track 2 */

    48

	0x1, /* Track 2 -> Track 1 */

    49

	0x30, /* Upper -> Left | Right */

    50

	0x30, /* Lower -> Left | Right */

    51

	0x0C, /* Left -> Upper | Lower */

    52

	0x0C, /* Right -> Upper | Lower */

    53

};

    54

    55

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

    56

 * that trackdir */

    57

const byte _trackdir_to_exitdir[14] = {

    58

	0,1,0,1,2,1, 0,0,

    59

	2,3,3,2,3,0,

    60

};

    61

    62

const byte _track_exitdir_to_trackdir[6][4] = {

    63

	{0,    0xff, 8,    0xff},

    64

	{0xff, 1,    0xff, 9},

    65

	{2,    0xff, 0xff, 10},

    66

	{0xff, 3,    11,   0xf},

    67

	{0xff, 0xff, 4,    12},

    68

	{13,   5,    0xff, 0xff}

    69

};

    70

    71

const byte _track_direction_to_trackdir[6][8] = {

    72

	{0xff, 0,    0xff, 0xff, 0xff, 8,    0xff, 0xff},

    73

	{0xff, 0xff, 0xff, 1,    0xff, 0xff, 0xff, 9},

    74

	{0xff, 0xff, 2,    0xff, 0xff, 0xff, 10,   0xff},

    75

	{0xff, 0xff, 3,    0xff, 0xff, 0xff, 11,   0xff},

    76

	{12,   0xff, 0xff, 0xff, 4,    0xff, 0xff, 0xff},

    77

	{13,   0xff, 0xff, 0xff, 5,    0xff, 0xff, 0xff}

    78

};

    79

    80

const byte _dir_to_diag_trackdir[4] = {

    81

	0, 1, 8, 9,

    82

};

    83

    84

const byte _reverse_dir[4] = {

    85

	2, 3, 0, 1

    86

};

    87

    88

const byte _reverse_trackdir[14] = {

    89

	8, 9, 10, 11, 12, 13, 0xFF, 0xFF,

    90

	0, 1, 2,  3,  4,  5

    91

};

    92

    93

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

    94

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

    95

 */

    96

#define NPF_STRAIGHT_LENGTH (uint)(NPF_TILE_LENGTH * 0.7071)

    97

static const uint _trackdir_length[14] = {

    98

NPF_TILE_LENGTH, NPF_TILE_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, 0, 0,

    99

NPF_TILE_LENGTH, NPF_TILE_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH

   100

};

   101

   102

uint NTPHash(uint key1, uint key2)

   103

{

   104

	return PATHFIND_HASH_TILE(key1);

   105

}

   106

   107

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

   108

	return 0;

   109

}

   110

   111

/* Calcs the heuristic to the target station (using NPFFindStationOrTileData). After

   112

 * will save the heuristic into NPFFoundTargetData if it is the smallest until

   113

 * now. It will then also save AyStarNode.user_data[NPF_TRACKDIR_CHOICE] in

   114

 * best_trackdir

   115

 */

   116

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

   117

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

   118

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

   119

	TileIndex from = current->tile;

   120

	TileIndex to = fstd->dest_coords;

   121

	uint dist = DistanceManhattan(from, to) * NPF_TILE_LENGTH;

   122

   123

	if (dist < ftd->best_bird_dist) {

   124

		ftd->best_bird_dist = dist;

   125

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

   126

	}

   127

	#ifdef NPF_DEBUG

   128

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

   129

	#endif

   130

	return dist;

   131

}

   132

   133

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

   134

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

   135

 * choice */

   136

void NPFFillTrackdirChoice(AyStarNode* current, OpenListNode* parent)

   137

{

   138

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

   139

		byte trackdir = current->direction;

   140

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

   141

		 * direction we chose */

   142

		current->user_data[NPF_TRACKDIR_CHOICE] = trackdir;

   143

		#ifdef NPF_DEBUG

   144

		debug("Saving trackdir: %#x", trackdir);

   145

		#endif

   146

	} else {

   147

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

   148

		 * decision */

   149

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

   150

	}

   151

   152

}

   153

   154

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

   155

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

   156

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

   157

uint NPFTunnelCost(AyStarNode* current) {

   158

	byte exitdir = _trackdir_to_exitdir[current->direction];

   159

	TileIndex tile = current->tile;

   160

	if ( (uint)(_map5[tile] & 3) == _reverse_dir[exitdir]) {

   161

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

   162

		 * facing the tunnel exit */

   163

		FindLengthOfTunnelResult flotr;

   164

		flotr = FindLengthOfTunnel(tile, _reverse_dir[exitdir]);

   165

		return flotr.length * NPF_TILE_LENGTH;

   166

		//TODO: Penalty for tunnels?

   167

	} else {

   168

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

   169

		 * straight track */

   170

		return NPF_TILE_LENGTH;

   171

	}

   172

}

   173

   174

uint NPFSlopeCost(AyStarNode* current) {

   175

	TileIndex next = current->tile + TileOffsByDir(_trackdir_to_exitdir[current->direction]);

   176

	if (GetTileZ(next) > GetTileZ(current->tile)) {

   177

		/* Slope up */

   178

		return _patches.npf_rail_slope_penalty;

   179

	}

   180

	return 0;

   181

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

   182

	 * could just substract that bonus from the penalty, because

   183

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

   184

}

   185

   186

void NPFMarkTile(TileIndex tile) {

   187

	switch(GetTileType(tile)) {

   188

		case MP_RAILWAY:

   189

		case MP_STREET:

   190

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

   191

			 * ;-) */

   192

			_map2[tile] &= ~15;

   193

			MarkTileDirtyByTile(tile);

   194

			break;

   195

		default:

   196

			break;

   197

	}

   198

}

   199

   200

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

   201

	//TileIndex tile = current->tile;

   202

	int32 cost = 0;

   203

	byte trackdir = current->direction;

   204

   205

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

   206

   207

	/* TODO Penalties? */

   208

   209

	return cost;

   210

}

   211

   212

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

   213

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

   214

	TileIndex tile = current->tile;

   215

	int32 cost = 0;

   216

	/* Determine base length */

   217

	switch (GetTileType(tile)) {

   218

		case MP_TUNNELBRIDGE:

   219

			if ((_map5[tile] & 0xF0)==0) {

   220

				cost = NPFTunnelCost(current);

   221

				break;

   222

			}

   223

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

   224

			 * then. We treat that as ordinary rail */

   225

		case MP_STREET:

   226

			cost = NPF_TILE_LENGTH;

   227

			break;

   228

		default:

   229

			break;

   230

	}

   231

   232

	/* Determine extra costs */

   233

   234

	/* Check for slope */

   235

	cost += NPFSlopeCost(current);

   236

   237

	/* Check for turns */

   238

	//TODO

   239

   240

	#ifdef NPF_MARKROUTE

   241

	NPFMarkTile(tile);

   242

	#endif

   243

	#ifdef NPF_DEBUG

   244

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

   245

	#endif

   246

	return cost;

   247

}

   248

   249

   250

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

   251

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

   252

	TileIndex tile = current->tile;

   253

	byte trackdir = current->direction;

   254

	int32 cost = 0;

   255

	/* Determine base length */

   256

	switch (GetTileType(tile)) {

   257

		case MP_TUNNELBRIDGE:

   258

			if ((_map5[tile] & 0xF0)==0) {

   259

				cost = NPFTunnelCost(current);

   260

				break;

   261

			}

   262

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

   263

			 * then. We treat that as ordinary rail */

   264

		case MP_RAILWAY:

   265

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

   266

			break;

   267

		case MP_STREET: /* Railway crossing */

   268

			cost = NPF_TILE_LENGTH;

   269

			break;

   270

		default:

   271

			break;

   272

	}

   273

   274

	/* Determine extra costs */

   275

   276

	/* Ordinary track with signals */

   277

	if (IsTileType(tile, MP_RAILWAY) && (_map5[tile] & 0xC0) == 0x40) {

   278

		if ((_map2[tile] & _signal_along_trackdir[trackdir]) == 0) {

   279

			/* Signal facing us is red */

   280

			if (!(current->user_data[NPF_NODE_FLAGS] & NPF_FLAG_SEEN_SIGNAL)) {

   281

				/* Penalize the first signal we

   282

				 * encounter, if it is red */

   283

				cost += _patches.npf_rail_firstred_penalty;

   284

			}

   285

		}

   286

		current->user_data[NPF_NODE_FLAGS] |= NPF_FLAG_SEEN_SIGNAL;

   287

	}

   288

   289

	/* Check for slope */

   290

	cost += NPFSlopeCost(current);

   291

   292

	/* Check for turns */

   293

	//TODO

   294

   295

	/* Check for occupied track */

   296

	//TODO

   297

   298

	/* Check for station tiles */

   299

	if (IsTileType(tile, MP_STATION)) {

   300

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

   301

		 * want to give station tiles that are not our destination

   302

		 * this penalty. This would discourage trains to drive through

   303

		 * busy stations. But, we can just give any station tile a

   304

		 * penalty, because every possible route will get this penalty

   305

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

   306

		 * will therefore not make a difference. */

   307

		cost += _patches.npf_rail_station_penalty;

   308

	}

   309

   310

	#ifdef NPF_MARKROUTE

   311

	NPFMarkTile(tile);

   312

	#endif

   313

	#ifdef NPF_DEBUG

   314

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

   315

	#endif

   316

	return cost;

   317

}

   318

   319

/* Will find any depot */

   320

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

   321

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

   322

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

   323

		return AYSTAR_FOUND_END_NODE;

   324

	else

   325

		return AYSTAR_DONE;

   326

}

   327

   328

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

   329

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

   330

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

   331

	 * is correct */

   332

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

   333

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

   334

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

   335

		(IsTileType(tile, MP_STATION) && _map2[tile] == fstd->station_index) /* the station */

   336

	   )

   337

			return AYSTAR_FOUND_END_NODE;

   338

	else

   339

		return AYSTAR_DONE;

   340

}

   341

   342

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

   343

 * Will fill the contents of the NPFFoundTargetData using

   344

 * AyStarNode[NPF_TRACKDIR_CHOICE].

   345

 */

   346

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

   347

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

   348

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

   349

	ftd->best_path_dist = current->g;

   350

	ftd->best_bird_dist = 0;

   351

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

   352

}

   353

   354

/* Will just follow the results of GetTileTrackStatus concerning where we can

   355

 * go and where not. Uses AyStar.user_data[NPF_TYPE] as the transport type and

   356

 * an argument to GetTileTrackStatus. Will skip tunnels, meaning that the

   357

 * entry and exit are neighbours. Will fill AyStarNode.user_data[NPF_TRACKDIR_CHOICE] with an

   358

 * appropriate value, and copy AyStarNode.user_data[NPF_NODE_FLAGS] from the

   359

 * parent */

   360

void NPFFollowTrack(AyStar* aystar, OpenListNode* current) {

   361

	byte src_trackdir = current->path.node.direction;

   362

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

   363

	byte src_exitdir = _trackdir_to_exitdir[src_trackdir];

   364

	FindLengthOfTunnelResult flotr;

   365

	TileIndex dst_tile;

   366

	int i = 0;

   367

	uint trackdirs, ts;

   368

	TransportType type = aystar->user_data[NPF_TYPE];

   369

	/* Initialize to 0, so we can jump out (return) somewhere an have no neighbours */

   370

	aystar->num_neighbours = 0;

   371

	#ifdef NPF_DEBUG

   372

	debug("Expanding: (%d, %d, %d) [%d]", TileX(src_tile), TileY(src_tile), src_trackdir, src_tile);

   373

	#endif

   374

   375

	/* Find dest tile */

   376

	if (IsTileType(src_tile, MP_TUNNELBRIDGE) && (_map5[src_tile] & 0xF0)==0 && (_map5[src_tile] & 3) == src_exitdir) {

   377

		/* This is a tunnel. We know this tunnel is our type,

   378

		 * otherwise we wouldn't have got here. It is also facing us,

   379

		 * so we should skip it's body */

   380

		flotr = FindLengthOfTunnel(src_tile, src_exitdir);

   381

		dst_tile = flotr.tile;

   382

	} else {

   383

		if (IsTileDepotType(src_tile, type)){

   384

			/* This is a road station or a train or road depot. We can enter and exit

   385

			 * those from one side only. Trackdirs don't support that (yet), so we'll

   386

			 * do this here. */

   387

   388

			byte exitdir;

   389

			/* Find out the exit direction first */

   390

			if (IsRoadStationTile(src_tile))

   391

				exitdir = GetRoadStationDir(src_tile);

   392

			else /* Train or road depot. Direction is stored the same for both, in map5 */

   393

				exitdir = _map5[src_tile] & 3; /* Extract the direction from the map */

   394

   395

			/* Let's see if were headed the right way */

   396

			if (src_trackdir != _dir_to_diag_trackdir[exitdir])

   397

				/* Not going out of the station/depot through the exit, but the back. No

   398

				 * neighbours then. */

   399

				return;

   400

		}

   401

		/* This a normal tile, a bridge, a tunnel exit, etc. */

   402

		dst_tile = AddTileIndexDiffCWrap(src_tile, TileIndexDiffCByDir(_trackdir_to_exitdir[src_trackdir]));

   403

		if (dst_tile == INVALID_TILE) {

   404

			/* We reached the border of the map */

   405

			/* TODO Nicer control flow for this */

   406

			return;

   407

		}

   408

	}

   409

   410

	// TODO: check correct rail type (mono, maglev, etc)

   411

   412

	/* Check the owner of the tile */

   413

	if (

   414

		IsTileType(dst_tile, MP_RAILWAY) /* Rail tile */

   415

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

   416

		|| IsTileType(dst_tile, MP_STATION) /* Station tile */

   417

		|| IsTileDepotType(dst_tile, TRANSPORT_WATER) /* Water depot tile */

   418

	) /* TODO: Crossings, tunnels and bridges are "public" now */

   419

		/* The above cases are "private" tiles, we need to check the owner */

   420

		if (!IsTileOwner(dst_tile, aystar->user_data[NPF_OWNER]))

   421

			return;

   422

   423

	/* Determine available tracks */

   424

	if (type == TRANSPORT_ROAD && (IsRoadStationTile(dst_tile) || IsTileDepotType(dst_tile, TRANSPORT_ROAD))){

   425

		/* Road stations and depots return 0 on GTTS, so we have to do this by hand... */

   426

		byte exitdir;

   427

		if (IsRoadStationTile(dst_tile))

   428

			exitdir = GetRoadStationDir(dst_tile);

   429

		else /* Road depot */

   430

			/* Find the trackdirs that are available for a depot with this orientation. They are in both directions */

   431

			exitdir = _map5[dst_tile] & 3; /* Extract the direction from the map */

   432

			ts = (1 << _dir_to_diag_trackdir[exitdir])

   433

			     | (1 << _dir_to_diag_trackdir[_reverse_dir[exitdir]]);

   434

	} else {

   435

		ts = GetTileTrackStatus(dst_tile, type);

   436

	}

   437

	trackdirs = ts & 0x3F3F; /* Filter out signal status and the unused bits */

   438

   439

	#ifdef NPF_DEBUG

   440

	debug("Next node: (%d, %d) [%d], possible trackdirs: %#x", TileX(dst_tile), TileY(dst_tile), dst_tile, trackdirs);

   441

	#endif

   442

	/* Select only trackdirs we can reach from our current trackdir */

   443

	trackdirs &= _trackdir_reaches_trackdirs[src_trackdir];

   444

	if (_patches.forbid_90_deg && (type == TRANSPORT_RAIL || type == TRANSPORT_WATER)) /* Filter out trackdirs that would make 90 deg turns for trains */

   445

		trackdirs &= ~_trackdir_crosses_trackdirs[src_trackdir];

   446

	#ifdef NPF_DEBUG

   447

	debug("After filtering: (%d, %d), possible trackdirs: %#x", TileX(dst_tile), TileY(dst_tile), trackdirs);

   448

	#endif

   449

   450

	/* Enumerate possible track */

   451

	while (trackdirs != 0) {

   452

		byte dst_trackdir;

   453

		dst_trackdir =  FindFirstBit2x64(trackdirs);

   454

		trackdirs = KillFirstBit2x64(trackdirs);

   455

		#ifdef NPF_DEBUG

   456

		debug("Expanded into trackdir: %d, remaining trackdirs: %#x", dst_trackdir, trackdirs);

   457

		#endif

   458

   459

		/* Check for oneway signal against us */

   460

		if (IsTileType(dst_tile, MP_RAILWAY) && (_map5[dst_tile]&0xC0) == 0x40) {

   461

			// the tile has a signal

   462

			byte signal_present = _map3_lo[dst_tile];

   463

			if (!(signal_present & _signal_along_trackdir[dst_trackdir])) {

   464

				// if one way signal not pointing towards us, stop going in this direction.

   465

				if (signal_present & _signal_against_trackdir[dst_trackdir])

   466

					break;

   467

			}

   468

		}

   469

		{

   470

			/* We've found ourselves a neighbour :-) */

   471

			AyStarNode* neighbour = &aystar->neighbours[i];

   472

			neighbour->tile = dst_tile;

   473

			neighbour->direction = dst_trackdir;

   474

			/* Save user data */

   475

			neighbour->user_data[NPF_NODE_FLAGS] = current->path.node.user_data[NPF_NODE_FLAGS];

   476

			NPFFillTrackdirChoice(neighbour, current);

   477

		}

   478

		i++;

   479

	}

   480

	aystar->num_neighbours = i;

   481

}

   482

   483

/*

   484

 * Plan a route to the specified target (which is checked by target_proc),

   485

 * from start1 and if not NULL, from start2 as well. The type of transport we

   486

 * are checking is in type.

   487

 * When we are looking for one specific target (optionally multiple tiles), we

   488

 * should use a good heuristic to perform aystar search. When we search for

   489

 * multiple targets that are spread around, we should perform a breadth first

   490

 * search by specifiying CalcZero as our heuristic.

   491

 */

   492

NPFFoundTargetData NPFRouteInternal(AyStarNode* start1, AyStarNode* start2, NPFFindStationOrTileData* target, AyStar_EndNodeCheck target_proc, AyStar_CalculateH heuristic_proc, TransportType type, Owner owner) {

   493

	int r;

   494

	NPFFoundTargetData result;

   495

   496

	/* Initialize procs */

   497

	_npf_aystar.CalculateH = heuristic_proc;

   498

	_npf_aystar.EndNodeCheck = target_proc;

   499

	_npf_aystar.FoundEndNode = NPFSaveTargetData;

   500

	_npf_aystar.GetNeighbours = NPFFollowTrack;

   501

	if (type == TRANSPORT_RAIL)

   502

		_npf_aystar.CalculateG = NPFRailPathCost;

   503

	else if (type == TRANSPORT_ROAD)

   504

		_npf_aystar.CalculateG = NPFRoadPathCost;

   505

	else if (type == TRANSPORT_WATER)

   506

		_npf_aystar.CalculateG = NPFWaterPathCost;

   507

	else

   508

		assert(0);

   509

   510

	/* Initialize Start Node(s) */

   511

	start1->user_data[NPF_TRACKDIR_CHOICE] = 0xff;

   512

	start1->user_data[NPF_NODE_FLAGS] = 0;

   513

	_npf_aystar.addstart(&_npf_aystar, start1);

   514

	if (start2) {

   515

		start2->user_data[NPF_TRACKDIR_CHOICE] = 0xff;

   516

		start2->user_data[NPF_NODE_FLAGS] = NPF_FLAG_REVERSE;

   517

		_npf_aystar.addstart(&_npf_aystar, start2);

   518

	}

   519

   520

	/* Initialize result */

   521

	result.best_bird_dist = (uint)-1;

   522

	result.best_path_dist = (uint)-1;

   523

	result.best_trackdir = 0xff;

   524

	_npf_aystar.user_path = &result;

   525

   526

	/* Initialize target */

   527

	_npf_aystar.user_target = target;