1

/* $Id$ */

     2

     3

#include "stdafx.h"

     4

#include "openttd.h"

     5

#include "debug.h"

     6

#include "functions.h"

     7

#include "npf.h"

     8

#include "aystar.h"

     9

#include "macros.h"

    10

#include "pathfind.h"

    11

#include "station.h"

    12

#include "tile.h"

    13

#include "depot.h"

    14

#include "tunnel_map.h"

    15

    16

static AyStar _npf_aystar;

    17

    18

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

    19

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

    20

 */

    21

#define NPF_STRAIGHT_LENGTH (uint)(NPF_TILE_LENGTH * STRAIGHT_TRACK_LENGTH)

    22

static const uint _trackdir_length[TRACKDIR_END] = {

    23

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

    24

	0, 0,

    25

	NPF_TILE_LENGTH, NPF_TILE_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH

    26

};

    27

    28

/**

    29

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

    30

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

    31

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

    32

 * prevent rounding.

    33

 */

    34

static uint NPFDistanceTrack(TileIndex t0, TileIndex t1)

    35

{

    36

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

    37

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

    38

    39

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

    40

	/* OPTIMISATION:

    41

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

    42

	 * Proof:

    43

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

    44

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

    45

    46

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

    47

	 * precision */

    48

	return diagTracks * NPF_TILE_LENGTH + straightTracks * NPF_TILE_LENGTH * STRAIGHT_TRACK_LENGTH;

    49

}

    50

    51

    52

#if 0

    53

static uint NTPHash(uint key1, uint key2)

    54

{

    55

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

    56

	return PATHFIND_HASH_TILE(key1);

    57

}

    58

#endif

    59

    60

/**

    61

 * Calculates a hash value for use in the NPF.

    62

 * @param key1	The TileIndex of the tile to hash

    63

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

    64

 *

    65

 * @todo	Think of a better hash.

    66

 */

    67

static uint NPFHash(uint key1, uint key2)

    68

{

    69

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

    70

	uint part1 = TileX(key1) & NPF_HASH_HALFMASK;

    71

	uint part2 = TileY(key1) & NPF_HASH_HALFMASK;

    72

    73

	assert(IsValidTrackdir(key2));

    74

	assert(IsValidTile(key1));

    75

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

    76

}

    77

    78

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

    79

{

    80

	return 0;

    81

}

    82

    83

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

    84

 * for this we assume the station is a rectangle,

    85

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

    86

 */

    87

static TileIndex CalcClosestStationTile(StationID station, TileIndex tile)

    88

{

    89

	const Station* st = GetStation(station);

    90

    91

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

    92

	uint miny = TileY(st->train_tile);

    93

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

    94

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

    95

	uint x;

    96

	uint y;

    97

    98

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

    99

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

   100

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

   101

   102

	// same for y coordinate, see above comment

   103

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

   104

   105

	// return the tile of our target coordinates

   106

	return TileXY(x, y);

   107

}

   108

   109

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

   110

 * takes into account the direction of approach.

   111

 */

   112

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

   113

{

   114

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

   115

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

   116

	TileIndex from = current->tile;

   117

	TileIndex to = fstd->dest_coords;

   118

	uint dist;

   119

   120

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

   121

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

   122

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

   123

   124

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

   125

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

   126

		dist = DistanceManhattan(from, to) * NPF_TILE_LENGTH;

   127

	} else {

   128

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

   129

		dist = NPFDistanceTrack(from, to);

   130

	}

   131

   132

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

   133

   134

	if (dist < ftd->best_bird_dist) {

   135

		ftd->best_bird_dist = dist;

   136

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

   137

	}

   138

	return dist;

   139

}

   140

   141

   142

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

   143

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

   144

 * choice */

   145

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

   146

{

   147

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

   148

		Trackdir trackdir = (Trackdir)current->direction;

   149

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

   150

		 * direction we chose */

   151

		current->user_data[NPF_TRACKDIR_CHOICE] = trackdir;

   152

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

   153

	} else {

   154

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

   155

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

   156

	}

   157

}

   158

   159

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

   160

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

   161

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

   162

static uint NPFTunnelCost(AyStarNode* current)

   163

{

   164

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

   165

	TileIndex tile = current->tile;

   166

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

   167

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

   168

		 * facing the tunnel exit */

   169

		FindLengthOfTunnelResult flotr;

   170

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

   171

		return flotr.length * NPF_TILE_LENGTH;

   172

		//TODO: Penalty for tunnels?

   173

	} else {

   174

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

   175

		 * straight track */

   176

		return NPF_TILE_LENGTH;

   177

	}

   178

}

   179

   180

static uint NPFSlopeCost(AyStarNode* current)

   181

{

   182

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

   183

	int x,y;

   184

	int8 z1,z2;

   185

   186

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

   187

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

   188

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

   189

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

   190

   191

	x = TileX(next) * TILE_SIZE;

   192

	y = TileY(next) * TILE_SIZE;

   193

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

   194

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

   195

   196

	if (z2 - z1 > 1) {

   197

		/* Slope up */

   198

		return _patches.npf_rail_slope_penalty;

   199

	}

   200

	return 0;

   201

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

   202

	 * could just substract that bonus from the penalty, because

   203

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

   204

}

   205

   206

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

   207

static void NPFMarkTile(TileIndex tile)

   208

{

   209

#ifdef NO_DEBUG_MESSAGES

   210

	return;

   211

#else

   212

	if (_debug_npf_level < 1) return;

   213

	switch (GetTileType(tile)) {

   214

		case MP_RAILWAY:

   215

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

   216

			if (!IsTileDepotType(tile, TRANSPORT_RAIL)) {

   217

				SB(_m[tile].m2, 0, 4, 0);

   218

				MarkTileDirtyByTile(tile);

   219

			}

   220

			break;

   221

   222

		case MP_STREET:

   223

			if (!IsTileDepotType(tile, TRANSPORT_ROAD)) {

   224

				SB(_m[tile].m4, 4, 3, 0);

   225

				MarkTileDirtyByTile(tile);

   226

			}

   227

			break;

   228

   229

		default:

   230

			break;

   231

	}

   232

#endif

   233

}

   234

   235

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

   236

{

   237

	//TileIndex tile = current->tile;

   238

	int32 cost = 0;

   239

	Trackdir trackdir = (Trackdir)current->direction;

   240

   241

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

   242

   243

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

   244

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

   245

   246

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

   247

		cost += _patches.npf_water_curve_penalty;

   248

   249

	/* TODO More penalties? */

   250

   251

	return cost;

   252

}

   253

   254

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

   255

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

   256

{

   257

	TileIndex tile = current->tile;

   258

	int32 cost = 0;

   259

   260

	/* Determine base length */

   261

	switch (GetTileType(tile)) {

   262

		case MP_TUNNELBRIDGE:

   264

				cost = NPFTunnelCost(current);

   267

			}

   268

			break;

   269

   270

		case MP_STREET:

   271

			cost = NPF_TILE_LENGTH;

   272

			/* Increase the cost for level crossings */

   273

			if (IsLevelCrossing(tile))

   274

				cost += _patches.npf_crossing_penalty;

   275

			break;

   276

   277

		default:

   278

			break;

   279

	}

   280

   281

	/* Determine extra costs */

   282

   283

	/* Check for slope */

   284

	cost += NPFSlopeCost(current);

   285

   286

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

   287

	 * represented by non-diagonal tracks */

   288

	if (!IsDiagonalTrackdir(current->direction))

   289

		cost += _patches.npf_road_curve_penalty;

   290

   291

	NPFMarkTile(tile);

   292

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

   293

	return cost;

   294

}

   295

   296

   297

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

   298

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

   299

{

   300

	TileIndex tile = current->tile;

   301

	Trackdir trackdir = (Trackdir)current->direction;

   302

	int32 cost = 0;

   303

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

   304

	OpenListNode new_node;

   305

   306

	/* Determine base length */

   307

	switch (GetTileType(tile)) {

   308

		case MP_TUNNELBRIDGE:

   310

				cost = NPFTunnelCost(current);

   311

				break;

   312

			}

   313

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

   314

			 * then. We treat that as ordinary rail */

   315

   316

		case MP_RAILWAY:

   317

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

   318

			break;

   319

   320

		case MP_STREET: /* Railway crossing */

   321

			cost = NPF_TILE_LENGTH;

   322

			break;

   323

   324

		case MP_STATION:

   325

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

   326

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

   327

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

   328

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

   329

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

   330

			 * will therefore not make a difference. */

   331

			cost = NPF_TILE_LENGTH + _patches.npf_rail_station_penalty;

   332

			break;

   333

   334

		default:

   335

			break;

   336

	}

   337

   338

	/* Determine extra costs */

   339

   340

	/* Check for signals */

   341

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

   342

		/* Ordinary track with signals */

   343

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

   344

			/* Signal facing us is red */

   345

			if (!NPFGetFlag(current, NPF_FLAG_SEEN_SIGNAL)) {

   346

				/* Penalize the first signal we

   347

				 * encounter, if it is red */

   348

   349

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

   350

				SignalType sigtype = GetSignalType(tile, TrackdirToTrack(trackdir));

   351

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

   352

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

   353

					cost += _patches.npf_rail_firstred_exit_penalty;

   354

				} else {

   355

					cost += _patches.npf_rail_firstred_penalty;

   356

				}

   357

			}

   358

			/* Record the state of this signal */

   359

			NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, true);

   360

		} else {

   361

			/* Record the state of this signal */

   362

			NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, false);

   363

		}

   364

		NPFSetFlag(current, NPF_FLAG_SEEN_SIGNAL, true);

   365

	}

   366

   367

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

   368

	 * red */

   369

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

   370

	 * of course... */

   371

	new_node.path.node = *current;

   372

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

   373

		cost += _patches.npf_rail_lastred_penalty;

   374

   375

	/* Check for slope */

   376

	cost += NPFSlopeCost(current);

   377

   378

	/* Check for turns */

   379

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

   380

		cost += _patches.npf_rail_curve_penalty;

   381

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

   382

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

   383

   384

	/* Check for reverse in depot */

   385

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

   386

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

   387

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

   388

		 * that) */

   389

		cost += _patches.npf_rail_depot_reverse_penalty;

   390

	}

   391

   392

	/* Check for occupied track */

   393

	//TODO

   394

   395

	NPFMarkTile(tile);

   396

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

   397

	return cost;

   398

}

   399

   400

/* Will find any depot */

   401

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

   402

{

   403

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

   404

   405

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

   406

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

   407

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

   408

		return AYSTAR_FOUND_END_NODE;

   409

	} else {

   410

		return AYSTAR_DONE;

   411

	}

   412

}

   413

   414

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

   415

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

   416

{

   417

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

   418

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

   419

	TileIndex tile = node->tile;

   420

   421

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

   422

	 * is correct */

   423

	if (

   424

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

   425

		(IsTileType(tile, MP_STATION) && _m[tile].m2 == fstd->station_index) /* the station */

   426

	) {

   427

		return AYSTAR_FOUND_END_NODE;

   428

	} else {

   429

		return AYSTAR_DONE;

   430

	}

   431

}

   432

   433

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

   434

 * Will fill the contents of the NPFFoundTargetData using

   435

 * AyStarNode[NPF_TRACKDIR_CHOICE].

   436

 */

   437

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

   438

{

   439

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

   440

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

   441

	ftd->best_path_dist = current->g;

   442

	ftd->best_bird_dist = 0;

   443

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

   444

}

   445

   446

/**

   447

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

   448

 * @param owner    The owner of the vehicle.

   449

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

   450

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

   451

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

   452

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

   453

 *                 maybe moved to another file too.

   454

 */

   455

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

   456

{

   457

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

   458

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

   459

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

   460

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

   461

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

   462

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

   463

	}

   464

   465

	switch (GetTileType(tile)) {

   466

		case MP_STREET:

   467

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

   468

			if (IsLevelCrossing(tile) && GetCrossingTransportType(tile, TrackdirToTrack(DiagdirToDiagTrackdir(enterdir))) == TRANSPORT_RAIL)

   469

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

   470

			break;

   471

   472

		case MP_TUNNELBRIDGE:

   473

#if 0

   474

/* OPTIMISATION: If we are on the middle of a bridge, we will not do the cpu

   475

 * intensive owner check, instead we will just assume that if the vehicle

   476

 * managed to get on the bridge, it is probably allowed to :-)

   477

 */

   478

			if ((_m[tile].m5 & 0xC6) == 0xC0 && GB(_m[tile].m5, 0, 1) == (enterdir & 0x1)) {

   479

				/* on the middle part of a railway bridge: find bridge ending */

   480

				while (IsTileType(tile, MP_TUNNELBRIDGE) && !((_m[tile].m5 & 0xC6) == 0x80)) {

   481

					tile += TileOffsByDir(GB(_m[tile].m5, 0, 1));

   482

				}

   483

			}

   484

			/* if we were on a railway middle part, we are now at a railway bridge ending */

   485

#endif

   487

					(_m[tile].m5 & 0xC6) == 0x80 || /* railway bridge ending */

   488

					((_m[tile].m5 & 0xF8) == 0xE0 && GB(_m[tile].m5, 0, 1) != (enterdir & 0x1))) { /* railway under bridge */

   489

				return IsTileOwner(tile, owner);

   490

			}

   491

			break;

   492