1

/* $Id$ */

     2

     3

#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"

    14

#include "tile.h"

    15

#include "depot.h"

    16

#include "tunnel_map.h"

    17

    18

static AyStar _npf_aystar;

    19

    20

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

    21

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

    22

 */

    23

#define NPF_STRAIGHT_LENGTH (uint)(NPF_TILE_LENGTH * STRAIGHT_TRACK_LENGTH)

    24

static const uint _trackdir_length[TRACKDIR_END] = {

    25

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

    26

	0, 0,

    27

	NPF_TILE_LENGTH, NPF_TILE_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH

    28

};

    29

    30

/**

    31

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

    32

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

    33

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

    34

 * prevent rounding.

    35

 */

    36

static uint NPFDistanceTrack(TileIndex t0, TileIndex t1)

    37

{

    38

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

    39

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

    40

    41

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

    42

	/* OPTIMISATION:

    43

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

    44

	 * Proof:

    45

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

    46

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

    47

    48

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

    49

	 * precision */

    50

	return diagTracks * NPF_TILE_LENGTH + straightTracks * NPF_TILE_LENGTH * STRAIGHT_TRACK_LENGTH;

    51

}

    52

    53

    54

#if 0

    55

static uint NTPHash(uint key1, uint key2)

    56

{

    57

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

    58

	return PATHFIND_HASH_TILE(key1);

    59

}

    60

#endif

    61

    62

/**

    63

 * Calculates a hash value for use in the NPF.

    64

 * @param key1	The TileIndex of the tile to hash

    65

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

    66

 *

    67

 * @todo	Think of a better hash.

    68

 */

    69

static uint NPFHash(uint key1, uint key2)

    70

{

    71

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

    72

	uint part1 = TileX(key1) & NPF_HASH_HALFMASK;

    73

	uint part2 = TileY(key1) & NPF_HASH_HALFMASK;

    74

    75

	assert(IsValidTrackdir(key2));

    76

	assert(IsValidTile(key1));

    77

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

    78

}

    79

    80

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

    81

{

    82

	return 0;

    83

}

    84

    85

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

    86

 * for this we assume the station is a rectangle,

    87

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

    88

 */

    89

static TileIndex CalcClosestStationTile(StationID station, TileIndex tile)

    90

{

    91

	const Station* st = GetStation(station);

    92

    93

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

    94

	uint miny = TileY(st->train_tile);

    95

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

    96

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

    97

	uint x;

    98

	uint y;

    99

   100

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

   101

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

   102

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

   103

   104

	// same for y coordinate, see above comment

   105

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

   106

   107

	// return the tile of our target coordinates

   108

	return TileXY(x, y);

   109

}

   110

   111

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

   112

 * takes into account the direction of approach.

   113

 */

   114

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

   115

{

   116

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

   117

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

   118

	TileIndex from = current->tile;

   119

	TileIndex to = fstd->dest_coords;

   120

	uint dist;

   121

   122

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

   123

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

   124

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

   125

   126

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

   127

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

   128

		dist = DistanceManhattan(from, to) * NPF_TILE_LENGTH;

   129

	} else {

   130

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

   131

		dist = NPFDistanceTrack(from, to);

   132

	}

   133

   134

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

   135

   136

	if (dist < ftd->best_bird_dist) {

   137

		ftd->best_bird_dist = dist;

   138

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

   139

	}

   140

	return dist;

   141

}

   142

   143

   144

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

   145

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

   146

 * choice */

   147

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

   148

{

   149

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

   150

		Trackdir trackdir = (Trackdir)current->direction;

   151

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

   152

		 * direction we chose */

   153

		current->user_data[NPF_TRACKDIR_CHOICE] = trackdir;

   154

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

   155

	} else {

   156

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

   157

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

   158

	}

   159

}

   160

   161

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

   162

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

   163

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

   164

static uint NPFTunnelCost(AyStarNode* current)

   165

{

   166

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

   167

	TileIndex tile = current->tile;

   168

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

   169

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

   170

		 * facing the tunnel exit */

   171

		FindLengthOfTunnelResult flotr;

   172

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

   173

		return flotr.length * NPF_TILE_LENGTH;

   174

		//TODO: Penalty for tunnels?

   175

	} else {

   176

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

   177

		 * straight track */

   178

		return NPF_TILE_LENGTH;

   179

	}

   180

}

   181

   182

static uint NPFSlopeCost(AyStarNode* current)

   183

{

   184

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

   185

	int x,y;

   186

	int8 z1,z2;

   187

   188

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

   189

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

   190

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

   191

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

   192

   193

	x = TileX(next) * TILE_SIZE;

   194

	y = TileY(next) * TILE_SIZE;

   195

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

   196

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

   197

   198

	if (z2 - z1 > 1) {

   199

		/* Slope up */

   200

		return _patches.npf_rail_slope_penalty;

   201

	}

   202

	return 0;

   203

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

   204

	 * could just substract that bonus from the penalty, because

   205

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

   206

}

   207

   208

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

   209

static void NPFMarkTile(TileIndex tile)

   210

{

   211

#ifdef NO_DEBUG_MESSAGES

   212

	return;

   213

#else

   214

	if (_debug_npf_level < 1) return;

   215

	switch (GetTileType(tile)) {

   216

		case MP_RAILWAY:

   217

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

   218

			if (!IsTileDepotType(tile, TRANSPORT_RAIL)) {

   219

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

   220

				MarkTileDirtyByTile(tile);

   221

			}

   222

			break;

   223

   224

		case MP_STREET:

   225

			if (!IsTileDepotType(tile, TRANSPORT_ROAD)) {

   226

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

   227

				MarkTileDirtyByTile(tile);

   228

			}

   229

			break;

   230

   231

		default:

   232

			break;

   233

	}

   234

#endif

   235

}

   236

   237

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

   238

{

   239

	//TileIndex tile = current->tile;

   240

	int32 cost = 0;

   241

	Trackdir trackdir = (Trackdir)current->direction;

   242

   243

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

   244

   245

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

   246

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

   247

   248

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

   249

		cost += _patches.npf_water_curve_penalty;

   250

   251

	/* TODO More penalties? */

   252

   253

	return cost;

   254

}

   255

   256

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

   257

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

   258

{

   259

	TileIndex tile = current->tile;

   260

	int32 cost = 0;

   261

   262

	/* Determine base length */

   263

	switch (GetTileType(tile)) {

   264

		case MP_TUNNELBRIDGE:

   265

			if (IsTunnel(tile)) {

   266

				cost = NPFTunnelCost(current);

   267

			} else {

   268

				cost = NPF_TILE_LENGTH;

   269

			}

   270

			break;

   271

   272

		case MP_STREET:

   273

			cost = NPF_TILE_LENGTH;

   274

			/* Increase the cost for level crossings */

   275

			if (IsLevelCrossing(tile))

   276

				cost += _patches.npf_crossing_penalty;

   277

			break;

   278

   279

		default:

   280

			break;

   281

	}

   282

   283

	/* Determine extra costs */

   284

   285

	/* Check for slope */

   286

	cost += NPFSlopeCost(current);

   287

   288

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

   289

	 * represented by non-diagonal tracks */

   290

	if (!IsDiagonalTrackdir(current->direction))

   291

		cost += _patches.npf_road_curve_penalty;

   292

   293

	NPFMarkTile(tile);

   294

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

   295

	return cost;

   296

}

   297

   298

   299

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

   300

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

   301

{

   302

	TileIndex tile = current->tile;

   303

	Trackdir trackdir = (Trackdir)current->direction;

   304

	int32 cost = 0;

   305

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

   306

	OpenListNode new_node;

   307

   308

	/* Determine base length */

   309

	switch (GetTileType(tile)) {

   310

		case MP_TUNNELBRIDGE:

   311

			if (IsTunnel(tile)) {

   312

				cost = NPFTunnelCost(current);

   313

				break;

   314

			}

   315

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

   316

			 * then. We treat that as ordinary rail */

   317

   318

		case MP_RAILWAY:

   319

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

   320

			break;

   321

   322

		case MP_STREET: /* Railway crossing */

   323

			cost = NPF_TILE_LENGTH;

   324

			break;

   325

   326

		case MP_STATION:

   327

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

   328

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

   329

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

   330

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

   331

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

   332

			 * will therefore not make a difference. */

   333

			cost = NPF_TILE_LENGTH + _patches.npf_rail_station_penalty;

   334

			break;

   335

   336

		default:

   337

			break;

   338

	}

   339

   340

	/* Determine extra costs */

   341

   342

	/* Check for signals */

   343

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

   344

		/* Ordinary track with signals */

   345

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

   346

			/* Signal facing us is red */

   347

			if (!NPFGetFlag(current, NPF_FLAG_SEEN_SIGNAL)) {

   348

				/* Penalize the first signal we

   349

				 * encounter, if it is red */

   350

   351

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

   352

				SignalType sigtype = GetSignalType(tile);

   353

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

   354

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

   355

					cost += _patches.npf_rail_firstred_exit_penalty;

   356

				} else {

   357

					cost += _patches.npf_rail_firstred_penalty;

   358

				}

   359

			}

   360

			/* Record the state of this signal */

   361

			NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, true);

   362

		} else {

   363

			/* Record the state of this signal */

   364

			NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, false);

   365

		}

   366

		NPFSetFlag(current, NPF_FLAG_SEEN_SIGNAL, true);

   367

	}

   368

   369

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

   370

	 * red */

   371

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

   372

	 * of course... */

   373

	new_node.path.node = *current;

   374

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

   375

		cost += _patches.npf_rail_lastred_penalty;

   376

   377

	/* Check for slope */

   378

	cost += NPFSlopeCost(current);

   379

   380

	/* Check for turns */

   381

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

   382

		cost += _patches.npf_rail_curve_penalty;

   383

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

   384

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

   385

   386

	/* Check for reverse in depot */

   387

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

   388

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

   389

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

   390

		 * that) */

   391

		cost += _patches.npf_rail_depot_reverse_penalty;

   392

	}

   393

   394

	/* Check for occupied track */

   395

	//TODO

   396

   397

	NPFMarkTile(tile);

   398

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

   399

	return cost;

   400

}

   401

   402

/* Will find any depot */

   403

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

   404

{

   405

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

   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

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

   410

		return AYSTAR_FOUND_END_NODE;

   411

	} else {

   412

		return AYSTAR_DONE;

   413

	}

   414

}

   415

   416

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

   417

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

   418

{

   419

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

   420

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

   421

	TileIndex tile = node->tile;

   422

   423

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

   424

	 * is correct */

   425

	if (

   426

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

   427

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

   428

	) {

   429

		return AYSTAR_FOUND_END_NODE;

   430

	} else {

   431

		return AYSTAR_DONE;

   432

	}

   433

}

   434

   435

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

   436

 * Will fill the contents of the NPFFoundTargetData using

   437

 * AyStarNode[NPF_TRACKDIR_CHOICE].

   438

 */

   439

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

   440

{

   441

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

   442

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

   443

	ftd->best_path_dist = current->g;

   444

	ftd->best_bird_dist = 0;

   445

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

   446

}

   447

   448

/**

   449

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

   450

 * @param owner    The owner of the vehicle.

   451

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

   452

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

   453

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

   454

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

   455

 *                 maybe moved to another file too.

   456

 */

   457

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

   458

{

   459

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

   461

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

   462

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

   463

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

   464

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

   465

	}

   466

   467

	switch (GetTileType(tile)) {

   468

		case MP_STREET:

   469

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

   470

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

   471

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

   472

			break;

   473

   474

		case MP_TUNNELBRIDGE:

   475

#if 0

   476

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

   477

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

   478

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

   479

 */

   480

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

   481

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

   482

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

   483

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

   484

				}

   485

			}

   486

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

   487

#endif

   488

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

   489

					(IsBridge(tile) && (

   490

						(

   491

							IsBridgeRamp(tile) &&

   492

							GetBridgeTransportType(tile) == TRANSPORT_RAIL