1

/* $Id$ */

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     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 "tile.h"

    14

#include "depot.h"

    15

#include "tunnel_map.h"

    16

    17

static AyStar _npf_aystar;

    18

    19

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

    20

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

    21

 */

    22

#define NPF_STRAIGHT_LENGTH (uint)(NPF_TILE_LENGTH * STRAIGHT_TRACK_LENGTH)

    23

static const uint _trackdir_length[TRACKDIR_END] = {

    24

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

    25

	0, 0,

    26

	NPF_TILE_LENGTH, NPF_TILE_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH

    27

};

    28

    29

/**

    30

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

    31

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

    32

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

    33

 * prevent rounding.

    34

 */

    35

static uint NPFDistanceTrack(TileIndex t0, TileIndex t1)

    36

{

    37

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

    38

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

    39

    40

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

    41

	/* OPTIMISATION:

    42

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

    43

	 * Proof:

    44

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

    45

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

    46

    47

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

    48

	 * precision */

    49

	return diagTracks * NPF_TILE_LENGTH + straightTracks * NPF_TILE_LENGTH * STRAIGHT_TRACK_LENGTH;

    50

}

    51

    52

    53

#if 0

    54

static uint NTPHash(uint key1, uint key2)

    55

{

    56

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

    57

	return PATHFIND_HASH_TILE(key1);

    58

}

    59

#endif

    60

    61

/**

    62

 * Calculates a hash value for use in the NPF.

    63

 * @param key1	The TileIndex of the tile to hash

    64

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

    65

 *

    66

 * @todo	Think of a better hash.

    67

 */

    68

static uint NPFHash(uint key1, uint key2)

    69

{

    70

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

    71

	uint part1 = TileX(key1) & NPF_HASH_HALFMASK;

    72

	uint part2 = TileY(key1) & NPF_HASH_HALFMASK;

    73

    74

	assert(IsValidTrackdir(key2));

    75

	assert(IsValidTile(key1));

    76

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

    77

}

    78

    79

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

    80

{

    81

	return 0;

    82

}

    83

    84

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

    85

 * for this we assume the station is a rectangle,

    86

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

    87

 */

    88

static TileIndex CalcClosestStationTile(StationID station, TileIndex tile)

    89

{

    90

	const Station* st = GetStation(station);

    91

    92

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

    93

	uint miny = TileY(st->train_tile);

    94

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

    95

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

    96

	uint x;

    97

	uint y;

    98

    99

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

   100

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

   101

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

   102

   103

	// same for y coordinate, see above comment

   104

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

   105

   106

	// return the tile of our target coordinates

   107

	return TileXY(x, y);

   108

}

   109

   110

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

   111

 * takes into account the direction of approach.

   112

 */

   113

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

   114

{

   115

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

   116

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

   117

	TileIndex from = current->tile;

   118

	TileIndex to = fstd->dest_coords;

   119

	uint dist;

   120

   121

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

   122

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

   123

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

   124

   125

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

   126

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

   127

		dist = DistanceManhattan(from, to) * NPF_TILE_LENGTH;

   128

	} else {

   129

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

   130

		dist = NPFDistanceTrack(from, to);

   131

	}

   132

   133

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

   134

   135

	if (dist < ftd->best_bird_dist) {

   136

		ftd->best_bird_dist = dist;

   137

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

   138

	}

   139

	return dist;

   140

}

   141

   142

   143

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

   144

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

   145

 * choice */

   146

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

   147

{

   148

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

   149

		Trackdir trackdir = (Trackdir)current->direction;

   150

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

   151

		 * direction we chose */

   152

		current->user_data[NPF_TRACKDIR_CHOICE] = trackdir;

   153

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

   154

	} else {

   155

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

   156

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

   157

	}

   158

}

   159

   160

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

   161

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

   162

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

   163

static uint NPFTunnelCost(AyStarNode* current)

   164

{

   165

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

   166

	TileIndex tile = current->tile;

   167

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

   168

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

   169

		 * facing the tunnel exit */

   170

		FindLengthOfTunnelResult flotr;

   171

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

   172

		return flotr.length * NPF_TILE_LENGTH;

   173

		//TODO: Penalty for tunnels?

   174

	} else {

   175

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

   176

		 * straight track */

   177

		return NPF_TILE_LENGTH;

   178

	}

   179

}

   180

   181

static uint NPFSlopeCost(AyStarNode* current)

   182

{

   183

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

   184

	int x,y;

   185

	int8 z1,z2;

   186

   187

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

   188

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

   189

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

   190

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

   191

   192

	x = TileX(next) * TILE_SIZE;

   193

	y = TileY(next) * TILE_SIZE;

   194

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

   195

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

   196

   197

	if (z2 - z1 > 1) {

   198

		/* Slope up */

   199

		return _patches.npf_rail_slope_penalty;

   200

	}

   201

	return 0;

   202

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

   203

	 * could just substract that bonus from the penalty, because

   204

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

   205

}

   206

   207

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

   208

static void NPFMarkTile(TileIndex tile)

   209

{

   210

#ifdef NO_DEBUG_MESSAGES

   211

	return;

   212

#else

   213

	if (_debug_npf_level < 1) return;

   214

	switch (GetTileType(tile)) {

   215

		case MP_RAILWAY:

   216

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

   217

			if (!IsTileDepotType(tile, TRANSPORT_RAIL)) {

   218

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

   219

				MarkTileDirtyByTile(tile);

   220

			}

   221

			break;

   222

   223

		case MP_STREET:

   224

			if (!IsTileDepotType(tile, TRANSPORT_ROAD)) {

   225

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

   226

				MarkTileDirtyByTile(tile);

   227

			}

   228

			break;

   229

   230

		default:

   231

			break;

   232

	}

   233

#endif

   234

}

   235

   236

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

   237

{

   238

	//TileIndex tile = current->tile;

   239

	int32 cost = 0;

   240

	Trackdir trackdir = (Trackdir)current->direction;

   241

   242

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

   243

   244

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

   245

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

   246

   247

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

   248

		cost += _patches.npf_water_curve_penalty;

   249

   250

	/* TODO More penalties? */

   251

   252

	return cost;

   253

}

   254

   255

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

   256

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

   257

{

   258

	TileIndex tile = current->tile;

   259

	int32 cost = 0;

   260

   261

	/* Determine base length */

   262

	switch (GetTileType(tile)) {

   263

		case MP_TUNNELBRIDGE:

   264

			if (IsTunnel(tile)) {

   265

				cost = NPFTunnelCost(current);

   266

			} else {

   267

				cost = NPF_TILE_LENGTH;

   268

			}

   269

			break;

   270

   271

		case MP_STREET:

   272

			cost = NPF_TILE_LENGTH;

   273

			/* Increase the cost for level crossings */

   274

			if (IsLevelCrossing(tile))

   275

				cost += _patches.npf_crossing_penalty;

   276

			break;

   277

   278

		default:

   279

			break;

   280

	}

   281

   282

	/* Determine extra costs */

   283

   284

	/* Check for slope */

   285

	cost += NPFSlopeCost(current);

   286

   287

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

   288

	 * represented by non-diagonal tracks */

   289

	if (!IsDiagonalTrackdir(current->direction))

   290

		cost += _patches.npf_road_curve_penalty;

   291

   292

	NPFMarkTile(tile);

   293

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

   294

	return cost;

   295

}

   296

   297

   298

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

   299

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

   300

{

   301

	TileIndex tile = current->tile;

   302

	Trackdir trackdir = (Trackdir)current->direction;

   303

	int32 cost = 0;

   304

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

   305

	OpenListNode new_node;

   306

   307

	/* Determine base length */

   308

	switch (GetTileType(tile)) {

   309

		case MP_TUNNELBRIDGE:

   310

			if (IsTunnel(tile)) {

   311

				cost = NPFTunnelCost(current);

   312

				break;

   313

			}

   314

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

   315

			 * then. We treat that as ordinary rail */

   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 (GetSignalState(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

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

   405

   406

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

   407

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

   408

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

   409

		return AYSTAR_FOUND_END_NODE;

   410

	} else {

   411

		return AYSTAR_DONE;

   412

	}

   413

}

   414

   415

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

   416

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

   417

{

   418

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

   419

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

   420

	TileIndex tile = node->tile;

   421

   422

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

   423

	 * is correct */

   424

	if (

   425

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

   426

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

   427

	) {

   428

		return AYSTAR_FOUND_END_NODE;

   429

	} else {

   430

		return AYSTAR_DONE;

   431

	}

   432

}

   433

   434

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

   435

 * Will fill the contents of the NPFFoundTargetData using

   436

 * AyStarNode[NPF_TRACKDIR_CHOICE].

   437

 */

   438

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

   439

{

   440

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

   441

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

   442

	ftd->best_path_dist = current->g;

   443

	ftd->best_bird_dist = 0;

   444

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

   445

}

   446

   447

/**

   448

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

   449

 * @param owner    The owner of the vehicle.

   450

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

   451

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

   452

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

   453

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

   454

 *                 maybe moved to another file too.

   455

 */

   456

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

   457

{

   458

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

   459

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

   460

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

   461

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

   462

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

   463

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

   464

	}

   465

   466

	switch (GetTileType(tile)) {

   467

		case MP_STREET:

   468

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

   469

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

   470

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

   471

			break;

   472

   473

		case MP_TUNNELBRIDGE:

   474

#if 0

   475

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

   476

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

   477

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

   478

 */

   479

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

   480

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

   481

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

   482

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

   483

				}

   484

			}

   485

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

   486

#endif

   487

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

   488

					(IsBridge(tile) && (

   489

						(

   490

							IsBridgeRamp(tile) &&

   491

							GetBridgeTransportType(tile) == TRANSPORT_RAIL

   492

						) || (