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/* $Id$ */

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/** @file npf.cpp */

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#include "stdafx.h"

     6

#include "openttd.h"

     7

#include "bridge_map.h"

     8

#include "debug.h"

     9

#include "functions.h"

    11

#include "npf.h"

    12

#include "aystar.h"

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#include "macros.h"

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#include "pathfind.h"

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#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"

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#include "tunnel_map.h"

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#include "network/network.h"

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#include "water_map.h"

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    23

static AyStar _npf_aystar;

    24

    25

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

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

    27

 */

    28

#define NPF_STRAIGHT_LENGTH (uint)(NPF_TILE_LENGTH * STRAIGHT_TRACK_LENGTH)

    29

static const uint _trackdir_length[TRACKDIR_END] = {

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

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	0, 0,

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	NPF_TILE_LENGTH, NPF_TILE_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH

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};

    34

    35

/**

    36

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

    37

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

    38

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

    39

 * prevent rounding.

    40

 */

    41

static uint NPFDistanceTrack(TileIndex t0, TileIndex t1)

    42

{

    43

	const uint dx = delta(TileX(t0), TileX(t1));

    44

	const uint dy = delta(TileY(t0), TileY(t1));

    45

    46

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

    47

	/* OPTIMISATION:

    48

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

    49

	 * Proof:

    50

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

    51

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

    52

    53

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

    54

	 * precision */

    55

	return diagTracks * NPF_TILE_LENGTH + straightTracks * NPF_TILE_LENGTH * STRAIGHT_TRACK_LENGTH;

    56

}

    57

    58

    59

#if 0

    60

static uint NTPHash(uint key1, uint key2)

    61

{

    62

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

    63

	return PATHFIND_HASH_TILE(key1);

    64

}

    65

#endif

    66

    67

/**

    68

 * Calculates a hash value for use in the NPF.

    69

 * @param key1 The TileIndex of the tile to hash

    70

 * @param key2 The Trackdir of the track on the tile.

    71

 *

    72

 * @todo Think of a better hash.

    73

 */

    74

static uint NPFHash(uint key1, uint key2)

    75

{

    76

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

    77

	uint part1 = TileX(key1) & NPF_HASH_HALFMASK;

    78

	uint part2 = TileY(key1) & NPF_HASH_HALFMASK;

    79

    80

	assert(IsValidTrackdir((Trackdir)key2));

    81

	assert(IsValidTile(key1));

    82

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

    83

}

    84

    85

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

    86

{

    87

	return 0;

    88

}

    89

    90

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

    91

 * for this we assume the station is a rectangle,

    92

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

    93

 */

    94

static TileIndex CalcClosestStationTile(StationID station, TileIndex tile)

    95

{

    96

	const Station* st = GetStation(station);

    97

    98

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

    99

	uint miny = TileY(st->train_tile);

   100

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

   101

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

   102

	uint x;

   103

	uint y;

   104

   105

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

   106

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

   107

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

   108

   109

	/* same for y coordinate, see above comment */

   110

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

   111

   112

	/* return the tile of our target coordinates */

   113

	return TileXY(x, y);

   114

}

   115

   116

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

   117

 * takes into account the direction of approach.

   118

 */

   119

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

   120

{

   121

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

   122

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

   123

	TileIndex from = current->tile;

   124

	TileIndex to = fstd->dest_coords;

   125

	uint dist;

   126

   127

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

   128

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

   129

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

   130

   131

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

   132

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

   133

		dist = DistanceManhattan(from, to) * NPF_TILE_LENGTH;

   134

	} else {

   135

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

   136

		dist = NPFDistanceTrack(from, to);

   137

	}

   138

   139

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

   140

   141

	if (dist < ftd->best_bird_dist) {

   142

		ftd->best_bird_dist = dist;

   143

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

   144

	}

   145

	return dist;

   146

}

   147

   148

   149

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

   150

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

   151

 * choice */

   152

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

   153

{

   154

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

   155

		Trackdir trackdir = (Trackdir)current->direction;

   156

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

   157

		 * direction we chose */

   158

		current->user_data[NPF_TRACKDIR_CHOICE] = trackdir;

   159

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

   160

	} else {

   161

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

   162

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

   163

	}

   164

}

   165

   166

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

   167

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

   168

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

   169

static uint NPFTunnelCost(AyStarNode* current)

   170

{

   171

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

   172

	TileIndex tile = current->tile;

   173

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

   174

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

   175

		 * facing the tunnel exit */

   176

		FindLengthOfTunnelResult flotr;

   177

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

   178

		return flotr.length * NPF_TILE_LENGTH;

   179

		/* @todo: Penalty for tunnels? */

   180

	} else {

   181

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

   182

		 * straight track */

   183

		return NPF_TILE_LENGTH;

   184

	}

   185

}

   186

   187

static inline uint NPFBridgeCost(AyStarNode *current)

   188

{

   189

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

   190

}

   191

   192

static uint NPFSlopeCost(AyStarNode* current)

   193

{

   194

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

   195

	int x,y;

   196

	int8 z1,z2;

   197

   198

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

   199

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

   200

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

   201

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

   202

   203

	x = TileX(next) * TILE_SIZE;

   204

	y = TileY(next) * TILE_SIZE;

   205

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

   206

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

   207

   208

	if (z2 - z1 > 1) {

   209

		/* Slope up */

   210

		return _patches.npf_rail_slope_penalty;

   211

	}

   212

	return 0;

   213

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

   214

	 * could just substract that bonus from the penalty, because

   215

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

   216

}

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   218

/**

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

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

   221

 */

   222

static void NPFMarkTile(TileIndex tile)

   223

{

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#ifndef NO_DEBUG_MESSAGES

   225

	if (_debug_npf_level < 1 || _networking) return;

   226

	switch (GetTileType(tile)) {

   227

		case MP_RAILWAY:

   228

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

   229

			if (!IsTileDepotType(tile, TRANSPORT_RAIL)) {

   230

				SetRailGroundType(tile, RAIL_GROUND_BARREN);

   231

				MarkTileDirtyByTile(tile);

   232

			}

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			break;

   234

   235

		case MP_STREET:

   236

			if (!IsTileDepotType(tile, TRANSPORT_ROAD)) {

   237

				SetRoadside(tile, ROADSIDE_BARREN);

   238

				MarkTileDirtyByTile(tile);

   239

			}

   240

			break;

   241

   242

		default:

   243

			break;

   244

	}

   245

#endif

   246

}

   247

   248

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

   249

{

   250

	/* TileIndex tile = current->tile; */

   251

	int32 cost = 0;

   252

	Trackdir trackdir = (Trackdir)current->direction;

   253

   254

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

   255

   256

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

   257

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

   258

   259

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

   260

		cost += _patches.npf_water_curve_penalty;

   261

   262

	/* @todo More penalties? */

   263

   264

	return cost;

   265

}

   266

   267

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

   268

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

   269

{

   270

	TileIndex tile = current->tile;

   271

	int32 cost = 0;

   272

   273

	/* Determine base length */

   274

	switch (GetTileType(tile)) {

   275

		case MP_TUNNELBRIDGE:

   276

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

   277

			break;

   278

   279

		case MP_STREET:

   280

			cost = NPF_TILE_LENGTH;

   281

			/* Increase the cost for level crossings */

   282

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

   283

			break;

   284

   285

		case MP_STATION:

   286

			cost = NPF_TILE_LENGTH;

   287

			/* Increase the cost for drive-through road stops */

   288

			if (IsDriveThroughStopTile(tile)) cost += _patches.npf_road_drive_through_penalty;

   289

			break;

   290

   291

		default:

   292

			break;

   293

	}

   294

   295

	/* Determine extra costs */

   296

   297

	/* Check for slope */

   298

	cost += NPFSlopeCost(current);

   299

   300

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

   301

	 * represented by non-diagonal tracks */

   302

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

   303

		cost += _patches.npf_road_curve_penalty;

   304

   305

	NPFMarkTile(tile);

   306

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

   307

	return cost;

   308

}

   309

   310

   311

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

   312

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

   313

{

   314

	TileIndex tile = current->tile;

   315

	Trackdir trackdir = (Trackdir)current->direction;

   316

	int32 cost = 0;

   317

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

   318

	OpenListNode new_node;

   319

   320

	/* Determine base length */

   321

	switch (GetTileType(tile)) {

   322

		case MP_TUNNELBRIDGE:

   323

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

   324

			break;

   325

   326

		case MP_RAILWAY:

   327

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

   328

			break;

   329

   330

		case MP_STREET: /* Railway crossing */

   331

			cost = NPF_TILE_LENGTH;

   332

			break;

   333

   334

		case MP_STATION:

   335

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

   336

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

   337

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

   338

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

   339

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

   340

			 * will therefore not make a difference. */

   341

			cost = NPF_TILE_LENGTH + _patches.npf_rail_station_penalty;

   342

			break;

   343

   344

		default:

   345

			break;

   346

	}

   347

   348

	/* Determine extra costs */

   349

   350

	/* Check for signals */

   351

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

   352

		/* Ordinary track with signals */

   353

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

   354

			/* Signal facing us is red */

   355

			if (!NPFGetFlag(current, NPF_FLAG_SEEN_SIGNAL)) {

   356

				/* Penalize the first signal we

   357

				 * encounter, if it is red */

   358

   359

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

   360

				SignalType sigtype = GetSignalType(tile);

   361

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

   362

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

   363

					cost += _patches.npf_rail_firstred_exit_penalty;

   364

				} else {

   365

					cost += _patches.npf_rail_firstred_penalty;

   366

				}

   367

			}

   368

			/* Record the state of this signal */

   369

			NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, true);

   370

		} else {

   371

			/* Record the state of this signal */

   372

			NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, false);

   373

		}

   374

		NPFSetFlag(current, NPF_FLAG_SEEN_SIGNAL, true);

   375

	}

   376

   377

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

   378

	 * red */

   379

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

   380

	 * of course... */

   381

	new_node.path.node = *current;

   382

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

   383

		cost += _patches.npf_rail_lastred_penalty;

   384

   385

	/* Check for slope */

   386

	cost += NPFSlopeCost(current);

   387

   388

	/* Check for turns */

   389

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

   390

		cost += _patches.npf_rail_curve_penalty;

   391

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

   392

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

   393

   394

	/* Check for reverse in depot */

   395

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

   396

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

   397

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

   398

		 * that) */

   399

		cost += _patches.npf_rail_depot_reverse_penalty;

   400

	}

   401

   402

	/* Check for occupied track */

   403

	//TODO

   404

   405

	NPFMarkTile(tile);

   406

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

   407

	return cost;

   408

}

   409

   410

/* Will find any depot */

   411

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

   412

{

   413

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

   414

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

   415

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

   416

		AYSTAR_FOUND_END_NODE : AYSTAR_DONE;

   417

}

   418

   419

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

   420

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

   421

{

   422

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

   423

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

   424

	TileIndex tile = node->tile;

   425

   426

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

   427

	 * is correct */

   428

	if (

   429

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

   430

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

   431

	) {

   432

		return AYSTAR_FOUND_END_NODE;

   433

	} else {

   434

		return AYSTAR_DONE;

   435

	}

   436

}

   437

   438

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

   439

 * Will fill the contents of the NPFFoundTargetData using

   440

 * AyStarNode[NPF_TRACKDIR_CHOICE].

   441

 */

   442

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

   443

{

   444

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

   445

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

   446

	ftd->best_path_dist = current->g;

   447

	ftd->best_bird_dist = 0;

   448

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

   449

}

   450

   451

/**

   452

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

   453

 * @param owner    The owner of the vehicle.

   454

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

   455

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

   456

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

   457

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

   458

 *                 maybe moved to another file too.

   459

 */

   460

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

   461

{

   462

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

   463

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

   464

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

   465

			IsStandardRoadStopTile(tile) || /* Road station tile (but not drive-through stops) */

   466

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

   467

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

   468

	}

   469

   470

	switch (GetTileType(tile)) {

   471

		case MP_STREET:

   472

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

   473

			if (IsLevelCrossing(tile) &&

   474

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

   475

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

   476

			}

   477

			break;

   478

   479

		case MP_TUNNELBRIDGE:

   480

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

   481

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

   482

				return IsTileOwner(tile, owner);

   483

			}

   484

			break;

   485

   486

		default:

   487

			break;

   488

	}

   489