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"

    13

#include "station_map.h"

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#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 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(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 + TileOffsByDiagDir(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_SIZE / 2, y + TILE_SIZE / 2);

   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_SIZE / 2, y + TILE_SIZE / 2);

   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

#ifndef NO_DEBUG_MESSAGES

   217

	if (_debug_npf_level < 1 || _networking) return;

   218

	switch (GetTileType(tile)) {

   219

		case MP_RAILWAY:

   220

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

   221

			if (!IsTileDepotType(tile, TRANSPORT_RAIL)) {

   222

				SetRailGroundType(tile, RAIL_GROUND_BARREN);

   223

				MarkTileDirtyByTile(tile);

   224

			}

   225

			break;

   226

   227

		case MP_STREET:

   228

			if (!IsTileDepotType(tile, TRANSPORT_ROAD)) {

   229

				SetRoadside(tile, ROADSIDE_BARREN);

   230

				MarkTileDirtyByTile(tile);

   231

			}

   232

			break;

   233

   234

		default:

   235

			break;

   236

	}

   237

#endif

   238

}

   239

   240

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

   241

{

   242

	//TileIndex tile = current->tile;

   243

	int32 cost = 0;

   244

	Trackdir trackdir = (Trackdir)current->direction;

   245

   246

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

   247

   248

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

   249

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

   250

   251

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

   252

		cost += _patches.npf_water_curve_penalty;

   253

   254

	/* TODO More penalties? */

   255

   256

	return cost;

   257

}

   258

   259

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

   260

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

   261

{

   262

	TileIndex tile = current->tile;

   263

	int32 cost = 0;

   264

   265

	/* Determine base length */

   266

	switch (GetTileType(tile)) {

   267

		case MP_TUNNELBRIDGE:

   268

			if (IsTunnel(tile)) {

   269

				cost = NPFTunnelCost(current);

   270

			} else {

   271

				cost = NPF_TILE_LENGTH;

   272

			}

   273

			break;

   274

   275

		case MP_STREET:

   276

			cost = NPF_TILE_LENGTH;

   277

			/* Increase the cost for level crossings */

   278

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

   279

			break;

   280

   281

		default:

   282

			break;

   283

	}

   284

   285

	/* Determine extra costs */

   286

   287

	/* Check for slope */

   288

	cost += NPFSlopeCost(current);

   289

   290

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

   291

	 * represented by non-diagonal tracks */

   292

	if (!IsDiagonalTrackdir(current->direction))

   293

		cost += _patches.npf_road_curve_penalty;

   294

   295

	NPFMarkTile(tile);

   296

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

   297

	return cost;

   298

}

   299

   300

   301

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

   302

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

   303

{

   304

	TileIndex tile = current->tile;

   305

	Trackdir trackdir = (Trackdir)current->direction;

   306

	int32 cost = 0;

   307

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

   308

	OpenListNode new_node;

   309

   310

	/* Determine base length */

   311

	switch (GetTileType(tile)) {

   312

		case MP_TUNNELBRIDGE:

   313

			if (IsTunnel(tile)) {

   314

				cost = NPFTunnelCost(current);

   315

				break;

   316

			}

   317

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

   318

			 * then. We treat that as ordinary rail */

   319

   320

		case MP_RAILWAY:

   321

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

   322

			break;

   323

   324

		case MP_STREET: /* Railway crossing */

   325

			cost = NPF_TILE_LENGTH;

   326

			break;

   327

   328

		case MP_STATION:

   329

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

   330

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

   331

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

   332

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

   333

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

   334

			 * will therefore not make a difference. */

   335

			cost = NPF_TILE_LENGTH + _patches.npf_rail_station_penalty;

   336

			break;

   337

   338

		default:

   339

			break;

   340

	}

   341

   342

	/* Determine extra costs */

   343

   344

	/* Check for signals */

   345

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

   346

		/* Ordinary track with signals */

   347

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

   348

			/* Signal facing us is red */

   349

			if (!NPFGetFlag(current, NPF_FLAG_SEEN_SIGNAL)) {

   350

				/* Penalize the first signal we

   351

				 * encounter, if it is red */

   352

   353

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

   354

				SignalType sigtype = GetSignalType(tile);

   355

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

   356

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

   357

					cost += _patches.npf_rail_firstred_exit_penalty;

   358

				} else {

   359

					cost += _patches.npf_rail_firstred_penalty;

   360

				}

   361

			}

   362

			/* Record the state of this signal */

   363

			NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, true);

   364

		} else {

   365

			/* Record the state of this signal */

   366

			NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, false);

   367

		}

   368

		NPFSetFlag(current, NPF_FLAG_SEEN_SIGNAL, true);

   369

	}

   370

   371

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

   372

	 * red */

   373

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

   374

	 * of course... */

   375

	new_node.path.node = *current;

   376

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

   377

		cost += _patches.npf_rail_lastred_penalty;

   378

   379

	/* Check for slope */

   380

	cost += NPFSlopeCost(current);

   381

   382

	/* Check for turns */

   383

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

   384

		cost += _patches.npf_rail_curve_penalty;

   385

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

   386

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

   387

   388

	/* Check for reverse in depot */

   389

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

   390

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

   391

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

   392

		 * that) */

   393

		cost += _patches.npf_rail_depot_reverse_penalty;

   394

	}

   395

   396

	/* Check for occupied track */

   397

	//TODO

   398

   399

	NPFMarkTile(tile);

   400

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

   401

	return cost;

   402

}

   403

   404

/* Will find any depot */

   405

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

   406

{

   407

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

   408

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

   409

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

   410

		AYSTAR_FOUND_END_NODE : AYSTAR_DONE;

   411

}

   412

   413

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

   414

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

   415

{

   416

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

   417

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

   418

	TileIndex tile = node->tile;

   419

   420

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

   421

	 * is correct */

   422

	if (

   423

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

   424

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

   425

	) {

   426

		return AYSTAR_FOUND_END_NODE;

   427

	} else {

   428

		return AYSTAR_DONE;

   429

	}

   430

}

   431

   432

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

   433

 * Will fill the contents of the NPFFoundTargetData using

   434

 * AyStarNode[NPF_TRACKDIR_CHOICE].

   435

 */

   436

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

   437

{

   438

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

   439

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

   440

	ftd->best_path_dist = current->g;

   441

	ftd->best_bird_dist = 0;

   442

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

   443

}

   444

   445

/**

   446

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

   447

 * @param owner    The owner of the vehicle.

   448

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

   449

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

   450

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

   451

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

   452

 *                 maybe moved to another file too.

   453

 */

   454

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

   455

{

   456

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

   457

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

   458

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

   459

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

   460

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

   461

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

   462

	}

   463

   464

	switch (GetTileType(tile)) {

   465

		case MP_STREET:

   466

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

   467

			if (IsLevelCrossing(tile) &&

   468

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

   469

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

   470

			}

   471

			break;

   472

   473

		case MP_TUNNELBRIDGE:

   474

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

   475

					(IsBridge(tile) && (

   476

						(

   477

							IsBridgeRamp(tile) &&

   478

							GetBridgeTransportType(tile) == TRANSPORT_RAIL

   479

						) || (

   480

							IsBridgeMiddle(tile) &&

   481

							IsTransportUnderBridge(tile) &&

   482

							GetTransportTypeUnderBridge(tile) == TRANSPORT_RAIL &&

   483

							GetBridgeAxis(tile) != DiagDirToAxis(enterdir)

   484

						)

   485

					))) {

   486

				return IsTileOwner(tile, owner);

   487

			}

   488

			break;

   489

   490

		default:

   491

			break;