1

/* $Id$ */

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#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"

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#include "station_map.h"

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#include "tile.h"

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#include "depot.h"

    16

#include "tunnel_map.h"

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#include "network/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 = delta(TileX(t0), TileX(t1));

    41

	const uint dy = delta(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 key2 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((Trackdir)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 = (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 inline uint NPFBridgeCost(AyStarNode *current)

   185

{

   186

	return NPF_TILE_LENGTH * GetBridgeLength(current->tile, GetOtherBridgeEnd(current->tile));

   187

}

   188

   189

static uint NPFSlopeCost(AyStarNode* current)

   190

{

   191

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

   192

	int x,y;

   193

	int8 z1,z2;

   194

   195

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

   196

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

   197

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

   198

	z1 = GetSlopeZ(x + TILE_SIZE / 2, y + TILE_SIZE / 2);

   199

   200

	x = TileX(next) * TILE_SIZE;

   201

	y = TileY(next) * TILE_SIZE;

   202

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

   203

	z2 = GetSlopeZ(x + TILE_SIZE / 2, y + TILE_SIZE / 2);

   204

   205

	if (z2 - z1 > 1) {

   206

		/* Slope up */

   207

		return _patches.npf_rail_slope_penalty;

   208

	}

   209

	return 0;

   210

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

   211

	 * could just substract that bonus from the penalty, because

   212

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

   213

}

   214

   215

/**

   216

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

   217

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

   218

 */

   219

static void NPFMarkTile(TileIndex tile)

   220

{

   221

#ifndef NO_DEBUG_MESSAGES

   222

	if (_debug_npf_level < 1 || _networking) return;

   223

	switch (GetTileType(tile)) {

   224

		case MP_RAILWAY:

   225

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

   226

			if (!IsTileDepotType(tile, TRANSPORT_RAIL)) {

   227

				SetRailGroundType(tile, RAIL_GROUND_BARREN);

   228

				MarkTileDirtyByTile(tile);

   229

			}

   230

			break;

   231

   232

		case MP_STREET:

   233

			if (!IsTileDepotType(tile, TRANSPORT_ROAD)) {

   234

				SetRoadside(tile, ROADSIDE_BARREN);

   235

				MarkTileDirtyByTile(tile);

   236

			}

   237

			break;

   238

   239

		default:

   240

			break;

   241

	}

   242

#endif

   243

}

   244

   245

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

   246

{

   247

	//TileIndex tile = current->tile;

   248

	int32 cost = 0;

   249

	Trackdir trackdir = (Trackdir)current->direction;

   250

   251

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

   252

   253

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

   254

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

   255

   256

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

   257

		cost += _patches.npf_water_curve_penalty;

   258

   259

	/* TODO More penalties? */

   260

   261

	return cost;

   262

}

   263

   264

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

   265

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

   266

{

   267

	TileIndex tile = current->tile;

   268

	int32 cost = 0;

   269

   270

	/* Determine base length */

   271

	switch (GetTileType(tile)) {

   272

		case MP_TUNNELBRIDGE:

   273

			cost = IsTunnel(tile) ? NPFTunnelCost(current) : NPFBridgeCost(current);

   274

			break;

   275

   276

		case MP_STREET:

   277

			cost = NPF_TILE_LENGTH;

   278

			/* Increase the cost for level crossings */

   279

			if (IsLevelCrossing(tile)) cost += _patches.npf_crossing_penalty;

   280

			break;

   281

   282

		default:

   283

			break;

   284

	}

   285

   286

	/* Determine extra costs */

   287

   288

	/* Check for slope */

   289

	cost += NPFSlopeCost(current);

   290

   291

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

   292

	 * represented by non-diagonal tracks */

   293

	if (!IsDiagonalTrackdir((Trackdir)current->direction))

   294

		cost += _patches.npf_road_curve_penalty;

   295

   296

	NPFMarkTile(tile);

   297

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

   298

	return cost;

   299

}

   300

   301

   302

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

   303

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

   304

{

   305

	TileIndex tile = current->tile;

   306

	Trackdir trackdir = (Trackdir)current->direction;

   307

	int32 cost = 0;

   308

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

   309

	OpenListNode new_node;

   310

   311

	/* Determine base length */

   312

	switch (GetTileType(tile)) {

   313

		case MP_TUNNELBRIDGE:

   314

			cost = IsTunnel(tile) ? NPFTunnelCost(current) : NPFBridgeCost(current);

   315

			break;

   316

   317

		case MP_RAILWAY:

   318

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

   319

			break;

   320

   321

		case MP_STREET: /* Railway crossing */

   322

			cost = NPF_TILE_LENGTH;

   323

			break;

   324

   325

		case MP_STATION:

   326

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

   327

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

   328

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

   329

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

   330

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

   331

			 * will therefore not make a difference. */

   332

			cost = NPF_TILE_LENGTH + _patches.npf_rail_station_penalty;

   333

			break;

   334

   335

		default:

   336

			break;

   337

	}

   338

   339

	/* Determine extra costs */

   340

   341

	/* Check for signals */

   342

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

   343

		/* Ordinary track with signals */

   344

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

   345

			/* Signal facing us is red */

   346

			if (!NPFGetFlag(current, NPF_FLAG_SEEN_SIGNAL)) {

   347

				/* Penalize the first signal we

   348

				 * encounter, if it is red */

   349

   350

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

   351

				SignalType sigtype = GetSignalType(tile);

   352

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

   353

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

   354

					cost += _patches.npf_rail_firstred_exit_penalty;

   355

				} else {

   356

					cost += _patches.npf_rail_firstred_penalty;

   357

				}

   358

			}

   359

			/* Record the state of this signal */

   360

			NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, true);

   361

		} else {

   362

			/* Record the state of this signal */

   363

			NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, false);

   364

		}

   365

		NPFSetFlag(current, NPF_FLAG_SEEN_SIGNAL, true);

   366

	}

   367

   368

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

   369

	 * red */

   370

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

   371

	 * of course... */

   372

	new_node.path.node = *current;

   373

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

   374

		cost += _patches.npf_rail_lastred_penalty;

   375

   376

	/* Check for slope */

   377

	cost += NPFSlopeCost(current);

   378

   379

	/* Check for turns */

   380

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

   381

		cost += _patches.npf_rail_curve_penalty;

   382

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

   383

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

   384

   385

	/* Check for reverse in depot */

   386

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

   387

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

   388

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

   389

		 * that) */

   390

		cost += _patches.npf_rail_depot_reverse_penalty;

   391

	}

   392

   393

	/* Check for occupied track */

   394

	//TODO

   395

   396

	NPFMarkTile(tile);

   397

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

   398

	return cost;

   399

}

   400

   401

/* Will find any depot */

   402

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

   403

{

   404

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

   405

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

   406

	return IsTileDepotType(current->path.node.tile, (TransportType)as->user_data[NPF_TYPE]) ?

   407

		AYSTAR_FOUND_END_NODE : AYSTAR_DONE;

   408

}

   409

   410

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

   411

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

   412

{

   413

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

   414

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

   415

	TileIndex tile = node->tile;

   416

   417

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

   418

	 * is correct */

   419

	if (

   420

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

   421

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

   422

	) {

   423

		return AYSTAR_FOUND_END_NODE;

   424

	} else {

   425

		return AYSTAR_DONE;

   426

	}

   427

}

   428

   429

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

   430

 * Will fill the contents of the NPFFoundTargetData using

   431

 * AyStarNode[NPF_TRACKDIR_CHOICE].

   432

 */

   433

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

   434

{

   435

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

   436

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

   437

	ftd->best_path_dist = current->g;

   438

	ftd->best_bird_dist = 0;

   439

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

   440

}

   441

   442

/**

   443

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

   444

 * @param owner    The owner of the vehicle.

   445

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

   446

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

   447

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

   448

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

   449

 *                 maybe moved to another file too.

   450

 */

   451

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

   452

{

   453

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

   454

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

   455

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

   456

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

   457

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

   458

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

   459

	}

   460

   461

	switch (GetTileType(tile)) {

   462

		case MP_STREET:

   463

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

   464

			if (IsLevelCrossing(tile) &&

   465

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

   466

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

   467

			}

   468

			break;

   469

   470

		case MP_TUNNELBRIDGE:

   471

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

   472

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

   473

				return IsTileOwner(tile, owner);

   474

			}

   475

			break;

   476

   477

		default:

   478

			break;

   479

	}

   480

   481

	return true; /* no need to check */

   482

}

   483

   484

   485

/**

   486

 * Returns the direction the exit of the depot on the given tile is facing.

   487

 */

   488

static DiagDirection GetDepotDirection(TileIndex tile, TransportType type)

   489

{

   490

	assert(IsTileDepotType(tile, type));