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/* $Id$ */

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#include "../../stdafx.h"

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#include "../../openttd.h"

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#include "../../bridge_map.h"

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#include "../../debug.h"

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#include "../../command_func.h"

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#include "trolly.h"

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#include "../../depot.h"

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#include "../../tunnel_map.h"

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#include "../../bridge.h"

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#include "../../tunnelbridge_map.h"

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#include "../ai.h"

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    15

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#define TEST_STATION_NO_DIR 0xFF

    17

    18

// Tests if a station can be build on the given spot

    19

// TODO: make it train compatible

    20

static bool TestCanBuildStationHere(TileIndex tile, byte dir)

    21

{

    22

	Player *p = GetPlayer(_current_player);

    23

    24

	if (dir == TEST_STATION_NO_DIR) {

    25

		CommandCost ret;

    26

		// TODO: currently we only allow spots that can be access from al 4 directions...

    27

		//  should be fixed!!!

    28

		for (dir = 0; dir < 4; dir++) {

    29

			ret = AiNew_Build_Station(p, p->ainew.tbt, tile, 1, 1, dir, DC_QUERY_COST);

    30

			if (CmdSucceeded(ret)) return true;

    31

		}

    32

		return false;

    33

	}

    34

    35

	// return true if command succeeded, so the inverse of CmdFailed()

    36

	return CmdSucceeded(AiNew_Build_Station(p, p->ainew.tbt, tile, 1, 1, dir, DC_QUERY_COST));

    37

}

    38

    39

    40

static bool IsRoad(TileIndex tile)

    41

{

    42

	return

    43

		// MP_ROAD, but not a road depot?

    44

		(IsTileType(tile, MP_ROAD) && !IsTileDepotType(tile, TRANSPORT_ROAD)) ||

    45

		(IsTileType(tile, MP_TUNNELBRIDGE) && GetTunnelBridgeTransportType(tile) == TRANSPORT_ROAD);

    46

}

    47

    48

    49

// Checks if a tile 'a' is between the tiles 'b' and 'c'

    50

#define TILES_BETWEEN(a, b, c) (TileX(a) >= TileX(b) && TileX(a) <= TileX(c) && TileY(a) >= TileY(b) && TileY(a) <= TileY(c))

    51

    52

    53

// Check if the current tile is in our end-area

    54

static int32 AyStar_AiPathFinder_EndNodeCheck(AyStar *aystar, OpenListNode *current)

    55

{

    56

	const Ai_PathFinderInfo* PathFinderInfo = (Ai_PathFinderInfo*)aystar->user_target;

    57

    58

	// It is not allowed to have a station on the end of a bridge or tunnel ;)

    59

	if (current->path.node.user_data[0] != 0) return AYSTAR_DONE;

    60

	if (TILES_BETWEEN(current->path.node.tile, PathFinderInfo->end_tile_tl, PathFinderInfo->end_tile_br))

    61

		if (IsTileType(current->path.node.tile, MP_CLEAR) || IsTileType(current->path.node.tile, MP_TREES))

    62

			if (current->path.parent == NULL || TestCanBuildStationHere(current->path.node.tile, AiNew_GetDirection(current->path.parent->node.tile, current->path.node.tile)))

    63

				return AYSTAR_FOUND_END_NODE;

    64

    65

	return AYSTAR_DONE;

    66

}

    67

    68

    69

// Calculates the hash

    70

//   Currently it is a 10 bit hash, so the hash array has a max depth of 6 bits (so 64)

    71

static uint AiPathFinder_Hash(uint key1, uint key2)

    72

{

    73

	return (TileX(key1) & 0x1F) + ((TileY(key1) & 0x1F) << 5);

    74

}

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    76

    77

// Clear the memory of all the things

    78

static void AyStar_AiPathFinder_Free(AyStar *aystar)

    79

{

    80

	AyStarMain_Free(aystar);

    81

	delete aystar;

    82

}

    83

    84

    85

static int32 AyStar_AiPathFinder_CalculateG(AyStar *aystar, AyStarNode *current, OpenListNode *parent);

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static int32 AyStar_AiPathFinder_CalculateH(AyStar *aystar, AyStarNode *current, OpenListNode *parent);

    87

static void AyStar_AiPathFinder_FoundEndNode(AyStar *aystar, OpenListNode *current);

    88

static void AyStar_AiPathFinder_GetNeighbours(AyStar *aystar, OpenListNode *current);

    89

    90

    91

// This creates the AiPathFinder

    92

AyStar *new_AyStar_AiPathFinder(int max_tiles_around, Ai_PathFinderInfo *PathFinderInfo)

    93

{

    94

	PathNode start_node;

    95

	uint x;

    96

	uint y;

    97

	// Create AyStar

    98

	AyStar *result = new AyStar();

    99

	init_AyStar(result, AiPathFinder_Hash, 1 << 10);

   100

	// Set the function pointers

   101

	result->CalculateG = AyStar_AiPathFinder_CalculateG;

   102

	result->CalculateH = AyStar_AiPathFinder_CalculateH;

   103

	result->EndNodeCheck = AyStar_AiPathFinder_EndNodeCheck;

   104

	result->FoundEndNode = AyStar_AiPathFinder_FoundEndNode;

   105

	result->GetNeighbours = AyStar_AiPathFinder_GetNeighbours;

   106

   107

	result->free = AyStar_AiPathFinder_Free;

   108

   109

	// Set some information

   110

	result->loops_per_tick = AI_PATHFINDER_LOOPS_PER_TICK;

   111

	result->max_path_cost = 0;

   112

	result->max_search_nodes = AI_PATHFINDER_MAX_SEARCH_NODES;

   113

   114

	// Set the user_data to the PathFinderInfo

   115

	result->user_target = PathFinderInfo;

   116

   117

	// Set the start node

   118

	start_node.parent = NULL;

   119

	start_node.node.direction = 0;

   120

	start_node.node.user_data[0] = 0;

   121

   122

	// Now we add all the starting tiles

   123

	for (x = TileX(PathFinderInfo->start_tile_tl); x <= TileX(PathFinderInfo->start_tile_br); x++) {

   124

		for (y = TileY(PathFinderInfo->start_tile_tl); y <= TileY(PathFinderInfo->start_tile_br); y++) {

   125

			start_node.node.tile = TileXY(x, y);

   126

			result->addstart(result, &start_node.node, 0);

   127

		}

   128

	}

   129

   130

	return result;

   131

}

   132

   133

   134

// To reuse AyStar we sometimes have to clean all the memory

   135

void clean_AyStar_AiPathFinder(AyStar *aystar, Ai_PathFinderInfo *PathFinderInfo)

   136

{

   137

	PathNode start_node;

   138

	uint x;

   139

	uint y;

   140

   141

	aystar->clear(aystar);

   142

   143

	// Set the user_data to the PathFinderInfo

   144

	aystar->user_target = PathFinderInfo;

   145

   146

	// Set the start node

   147

	start_node.parent = NULL;

   148

	start_node.node.direction = 0;

   149

	start_node.node.user_data[0] = 0;

   150

	start_node.node.tile = PathFinderInfo->start_tile_tl;

   151

   152

	// Now we add all the starting tiles

   153

	for (x = TileX(PathFinderInfo->start_tile_tl); x <= TileX(PathFinderInfo->start_tile_br); x++) {

   154

		for (y = TileY(PathFinderInfo->start_tile_tl); y <= TileY(PathFinderInfo->start_tile_br); y++) {

   155

			TileIndex tile = TileXY(x, y);

   156

   157

			if (!IsTileType(tile, MP_CLEAR) && !IsTileType(tile, MP_TREES)) continue;

   158

			if (!TestCanBuildStationHere(tile, TEST_STATION_NO_DIR)) continue;

   159

			start_node.node.tile = tile;

   160

			aystar->addstart(aystar, &start_node.node, 0);

   161

		}

   162

	}

   163

}

   164

   165

   166

// The h-value, simple calculation

   167

static int32 AyStar_AiPathFinder_CalculateH(AyStar *aystar, AyStarNode *current, OpenListNode *parent)

   168

{

   169

	const Ai_PathFinderInfo* PathFinderInfo = (Ai_PathFinderInfo*)aystar->user_target;

   170

	int r, r2;

   171

   172

	if (PathFinderInfo->end_direction != AI_PATHFINDER_NO_DIRECTION) {

   173

		// The station is pointing to a direction, add a tile towards that direction, so the H-value is more accurate

   174

		r = DistanceManhattan(current->tile, PathFinderInfo->end_tile_tl + TileOffsByDiagDir(PathFinderInfo->end_direction));

   175

		r2 = DistanceManhattan(current->tile, PathFinderInfo->end_tile_br + TileOffsByDiagDir(PathFinderInfo->end_direction));

   176

	} else {

   177

		// No direction, so just get the fastest route to the station

   178

		r = DistanceManhattan(current->tile, PathFinderInfo->end_tile_tl);

   179

		r2 = DistanceManhattan(current->tile, PathFinderInfo->end_tile_br);

   180

	}

   181

	// See if the bottomright is faster than the topleft..

   182

	if (r2 < r) r = r2;

   183

	return r * AI_PATHFINDER_H_MULTIPLER;

   184

}

   185

   186

   187

// We found the end.. let's get the route back and put it in an array

   188

static void AyStar_AiPathFinder_FoundEndNode(AyStar *aystar, OpenListNode *current)

   189

{

   190

	Ai_PathFinderInfo *PathFinderInfo = (Ai_PathFinderInfo*)aystar->user_target;

   191

	uint i = 0;

   192

	PathNode *parent = &current->path;

   193

   194

	do {

   195

		PathFinderInfo->route_extra[i] = parent->node.user_data[0];

   196

		PathFinderInfo->route[i++] = parent->node.tile;

   197

		if (i > lengthof(PathFinderInfo->route)) {

   198

			// We ran out of space for the PathFinder

   199

			DEBUG(ai, 0, "No more space in pathfinder route[] array");

   200

			PathFinderInfo->route_length = -1; // -1 indicates out of space

   201

			return;

   202

		}

   203

		parent = parent->parent;

   204

	} while (parent != NULL);

   205

	PathFinderInfo->route_length = i;

   206

	DEBUG(ai, 1, "Found route of %d nodes long in %d nodes of searching", i, Hash_Size(&aystar->ClosedListHash));

   207

}

   208

   209

   210

// What tiles are around us.

   211

static void AyStar_AiPathFinder_GetNeighbours(AyStar *aystar, OpenListNode *current)

   212

{

   213

	CommandCost ret;

   214

	int dir;

   215

   216

	Ai_PathFinderInfo *PathFinderInfo = (Ai_PathFinderInfo*)aystar->user_target;

   217

   218

	aystar->num_neighbours = 0;

   219

   220

	// Go through all surrounding tiles and check if they are within the limits

   221

	for (DiagDirection i = DIAGDIR_BEGIN; i < DIAGDIR_END; i++) {

   222

		TileIndex ctile = current->path.node.tile; // Current tile

   223

		TileIndex atile = ctile + TileOffsByDiagDir(i); // Adjacent tile

   224

   225

		if (TileX(atile) > 1 && TileX(atile) < MapMaxX() - 1 &&

   226

				TileY(atile) > 1 && TileY(atile) < MapMaxY() - 1) {

   227

			// We also directly test if the current tile can connect to this tile..

   228

			//  We do this simply by just building the tile!

   229

   230

			// If the next step is a bridge, we have to enter it the right way

   231

			if (!PathFinderInfo->rail_or_road && IsRoad(atile)) {

   232

				if (IsTileType(atile, MP_TUNNELBRIDGE)) {

   233

					if (GetTunnelBridgeDirection(atile) != i) continue;

   234

				}

   235

			}

   236

   237

			if ((AI_PATHFINDER_FLAG_BRIDGE & current->path.node.user_data[0]) != 0 ||

   238

					(AI_PATHFINDER_FLAG_TUNNEL & current->path.node.user_data[0]) != 0) {

   239

				// We are a bridge/tunnel, how cool!!

   240

				//  This means we can only point forward.. get the direction from the user_data

   241

				if ((uint)i != (current->path.node.user_data[0] >> 8)) continue;

   242

			}

   243

			dir = 0;

   244

   245

			// First, check if we have a parent

   246

			if (current->path.parent == NULL && current->path.node.user_data[0] == 0) {

   247

				// If not, this means we are at the starting station

   248

				if (PathFinderInfo->start_direction != AI_PATHFINDER_NO_DIRECTION) {

   249

					// We do need a direction?

   250

					if (AiNew_GetDirection(ctile, atile) != PathFinderInfo->start_direction) {

   251

						// We are not pointing the right way, invalid tile

   252

						continue;

   253

					}

   254

				}

   255

			} else if (current->path.node.user_data[0] == 0) {

   256

				if (PathFinderInfo->rail_or_road) {

   257

					// Rail check

   258

					dir = AiNew_GetRailDirection(current->path.parent->node.tile, ctile, atile);

   259

					ret = AI_DoCommand(ctile, 0, dir, DC_AUTO | DC_NO_WATER, CMD_BUILD_SINGLE_RAIL);

   260

					if (CmdFailed(ret)) continue;

   261

#ifdef AI_PATHFINDER_NO_90DEGREES_TURN

   262

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

   263

						// Check if we don't make a 90degree curve

   264

						int dir1 = AiNew_GetRailDirection(current->path.parent->parent->node.tile, current->path.parent->node.tile, ctile);

   265

						if (_illegal_curves[dir1] == dir || _illegal_curves[dir] == dir1) {

   266

							continue;

   267

						}

   268

					}

   269

#endif

   270

				} else {

   271

					// Road check

   272

					dir = AiNew_GetRoadDirection(current->path.parent->node.tile, ctile, atile);

   273

					if (IsRoad(ctile)) {

   274

						if (IsTileType(ctile, MP_TUNNELBRIDGE)) {

   275

							// We have a bridge, how nicely! We should mark it...

   276

							dir = 0;

   277

						} else {

   278

							// It already has road.. check if we miss any bits!

   279

							if ((GetAnyRoadBits(ctile, ROADTYPE_ROAD) & dir) != dir) {

   280

								// We do miss some pieces :(

   281

								dir &= ~GetAnyRoadBits(ctile, ROADTYPE_ROAD);

   282

							} else {

   283

								dir = 0;

   284

							}

   285

						}

   286

					}

   287

					// Only destruct things if it is MP_CLEAR of MP_TREES

   288

					if (dir != 0) {

   289

						ret = AI_DoCommand(ctile, dir, 0, DC_AUTO | DC_NO_WATER, CMD_BUILD_ROAD);

   290

						if (CmdFailed(ret)) continue;

   291

					}

   292

				}

   293

			}

   294

   295

			// The tile can be connected

   296

			aystar->neighbours[aystar->num_neighbours].tile = atile;

   297

			aystar->neighbours[aystar->num_neighbours].user_data[0] = 0;

   298

			aystar->neighbours[aystar->num_neighbours++].direction = 0;

   299

		}

   300

	}

   301

   302

	// Next step, check for bridges and tunnels

   303

	if (current->path.parent != NULL && current->path.node.user_data[0] == 0) {

   304

		// First we get the dir from this tile and his parent

   305

		DiagDirection dir = AiNew_GetDirection(current->path.parent->node.tile, current->path.node.tile);

   306

		// It means we can only walk with the track, so the bridge has to be in the same direction

   307

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

   308

		TileIndex new_tile = tile;

   309

		Slope tileh = GetTileSlope(tile, NULL);

   310

   311

		// Bridges can only be build on land that is not flat

   312

		//  And if there is a road or rail blocking

   313

		if (tileh != SLOPE_FLAT ||

   314

				(PathFinderInfo->rail_or_road && IsTileType(tile + TileOffsByDiagDir(dir), MP_ROAD)) ||

   315

				(!PathFinderInfo->rail_or_road && IsTileType(tile + TileOffsByDiagDir(dir), MP_RAILWAY))) {

   316

			for (;;) {

   317

				new_tile += TileOffsByDiagDir(dir);

   318

   319

				// Precheck, is the length allowed?

   320

				if (!CheckBridge_Stuff(0, GetBridgeLength(tile, new_tile))) break;

   321

   322

				// Check if we hit the station-tile.. we don't like that!

   323

				if (TILES_BETWEEN(new_tile, PathFinderInfo->end_tile_tl, PathFinderInfo->end_tile_br)) break;

   324

   325

				// Try building the bridge..

   326

				ret = AI_DoCommand(tile, new_tile, (0 << 8) + (MAX_BRIDGES / 2), DC_AUTO, CMD_BUILD_BRIDGE);

   327

				if (CmdFailed(ret)) continue;

   328

				// We can build a bridge here.. add him to the neighbours

   329

				aystar->neighbours[aystar->num_neighbours].tile = new_tile;

   330

				aystar->neighbours[aystar->num_neighbours].user_data[0] = AI_PATHFINDER_FLAG_BRIDGE + (dir << 8);

   331

				aystar->neighbours[aystar->num_neighbours++].direction = 0;

   332

				// We can only have 12 neighbours, and we need 1 left for tunnels

   333

				if (aystar->num_neighbours == 11) break;

   334

			}

   335

		}

   336

   337

		// Next, check for tunnels!

   338

		// Tunnels can only be built on slopes corresponding to the direction

   339

		//  For now, we check both sides for this tile.. terraforming gives fuzzy result

   340

		if ((dir == DIAGDIR_NE && tileh == SLOPE_NE) ||

   341

				(dir == DIAGDIR_SE && tileh == SLOPE_SE) ||

   342

				(dir == DIAGDIR_SW && tileh == SLOPE_SW) ||

   343

				(dir == DIAGDIR_NW && tileh == SLOPE_NW)) {

   344

			// Now simply check if a tunnel can be build

   345

			ret = AI_DoCommand(tile, (PathFinderInfo->rail_or_road?0:0x200), 0, DC_AUTO, CMD_BUILD_TUNNEL);

   346

			tileh = GetTileSlope(_build_tunnel_endtile, NULL);

   347

			if (CmdSucceeded(ret) && (tileh == SLOPE_SW || tileh == SLOPE_SE || tileh == SLOPE_NW || tileh == SLOPE_NE)) {

   348

				aystar->neighbours[aystar->num_neighbours].tile = _build_tunnel_endtile;

   349

				aystar->neighbours[aystar->num_neighbours].user_data[0] = AI_PATHFINDER_FLAG_TUNNEL + (dir << 8);

   350

				aystar->neighbours[aystar->num_neighbours++].direction = 0;

   351

			}

   352

		}

   353

	}

   354

}

   355

   356

   357

extern Foundation GetRailFoundation(Slope tileh, TrackBits bits); // XXX function declaration in .c

   358

extern Foundation GetRoadFoundation(Slope tileh, RoadBits bits); // XXX function declaration in .c

   359

extern Foundation GetBridgeFoundation(Slope tileh, Axis); // XXX function declaration in .c

   360

enum BridgeFoundation {

   361

	BRIDGE_NO_FOUNDATION = 1 << 0 | 1 << 3 | 1 << 6 | 1 << 9 | 1 << 12,

   362

};

   363

   364

// The most important function: it calculates the g-value

   365

static int32 AyStar_AiPathFinder_CalculateG(AyStar *aystar, AyStarNode *current, OpenListNode *parent)

   366

{

   367

	Ai_PathFinderInfo *PathFinderInfo = (Ai_PathFinderInfo*)aystar->user_target;

   368

	int res = 0;

   369

	Slope tileh = GetTileSlope(current->tile, NULL);

   370

	Slope parent_tileh = GetTileSlope(parent->path.node.tile, NULL);

   371

   372

	// Check if we hit the end-tile

   373

	if (TILES_BETWEEN(current->tile, PathFinderInfo->end_tile_tl, PathFinderInfo->end_tile_br)) {

   374

		// We are at the end-tile, check if we had a direction or something...

   375

		if (PathFinderInfo->end_direction != AI_PATHFINDER_NO_DIRECTION && AiNew_GetDirection(current->tile, parent->path.node.tile) != PathFinderInfo->end_direction) {

   376

			// We are not pointing the right way, invalid tile

   377

			return AYSTAR_INVALID_NODE;

   378

		}

   379

		// If it was valid, drop out.. we don't build on the endtile

   380

		return 0;

   381

	}

   382

   383

	// Give everything a small penalty

   384

	res += AI_PATHFINDER_PENALTY;

   385

   386

	if (!PathFinderInfo->rail_or_road) {

   387

		// Road has the lovely advantage it can use other road... check if

   388

		//  the current tile is road, and if so, give a good bonus

   389

		if (IsRoad(current->tile)) {

   390

			res -= AI_PATHFINDER_ROAD_ALREADY_EXISTS_BONUS;

   391

		}

   392

	}

   393

   394

	// We should give a penalty when the tile is going up or down.. this is one way to do so!

   395

	//  Too bad we have to count it from the parent.. but that is not so bad.

   396

	// We also dislike long routes on slopes, since they do not look too realistic

   397

	//  when there is a flat land all around, they are more expensive to build, and

   398

	//  especially they essentially block the ability to connect or cross the road

   399

	//  from one side.

   400

	if (parent_tileh != SLOPE_FLAT && parent->path.parent != NULL) {

   401

		// Skip if the tile was from a bridge or tunnel

   402

		if (parent->path.node.user_data[0] == 0 && current->user_data[0] == 0) {

   403

			if (PathFinderInfo->rail_or_road) {

   404

				Foundation f = GetRailFoundation(parent_tileh, (TrackBits)(1 << AiNew_GetRailDirection(parent->path.parent->node.tile, parent->path.node.tile, current->tile)));

   405

				// Maybe is BRIDGE_NO_FOUNDATION a bit strange here, but it contains just the right information..

   406

				if (IsInclinedFoundation(f) || (!IsFoundation(f) && HasBit(BRIDGE_NO_FOUNDATION, parent_tileh))) {

   407

					res += AI_PATHFINDER_TILE_GOES_UP_PENALTY;

   408

				} else {

   409

					res += AI_PATHFINDER_FOUNDATION_PENALTY;

   410

				}

   411

			} else {

   412

				if (!IsRoad(parent->path.node.tile) || !IsTileType(parent->path.node.tile, MP_TUNNELBRIDGE)) {

   413

					Foundation f = GetRoadFoundation(parent_tileh, (RoadBits)AiNew_GetRoadDirection(parent->path.parent->node.tile, parent->path.node.tile, current->tile));

   414

					if (IsInclinedFoundation(f) || (!IsFoundation(f) && HasBit(BRIDGE_NO_FOUNDATION, parent_tileh))) {

   415

						res += AI_PATHFINDER_TILE_GOES_UP_PENALTY;

   416

					} else {

   417

						res += AI_PATHFINDER_FOUNDATION_PENALTY;

   418

					}

   419

				}

   420

			}

   421

		}

   422

	}

   423

   424

	// Are we part of a tunnel?

   425

	if ((AI_PATHFINDER_FLAG_TUNNEL & current->user_data[0]) != 0) {

   426

		int r;

   427

		// Tunnels are very expensive when build on long routes..

   428

		// Ironicly, we are using BridgeCode here ;)

   429

		r = AI_PATHFINDER_TUNNEL_PENALTY * GetBridgeLength(current->tile, parent->path.node.tile);

   430

		res += r + (r >> 8);

   431

	}

   432

   433

	// Are we part of a bridge?

   434

	if ((AI_PATHFINDER_FLAG_BRIDGE & current->user_data[0]) != 0) {

   435

		// That means for every length a penalty

   436

		res += AI_PATHFINDER_BRIDGE_PENALTY * GetBridgeLength(current->tile, parent->path.node.tile);

   437

		// Check if we are going up or down, first for the starting point

   438

		// In user_data[0] is at the 8th bit the direction

   439

		if (!HasBit(BRIDGE_NO_FOUNDATION, parent_tileh)) {

   440

			if (IsLeveledFoundation(GetBridgeFoundation(parent_tileh, (Axis)((current->user_data[0] >> 8) & 1)))) {

   441

				res += AI_PATHFINDER_BRIDGE_GOES_UP_PENALTY;

   442

			}

   443

		}

   444

		// Second for the end point

   445

		if (!HasBit(BRIDGE_NO_FOUNDATION, tileh)) {

   446

			if (IsLeveledFoundation(GetBridgeFoundation(tileh, (Axis)((current->user_data[0] >> 8) & 1)))) {

   447

				res += AI_PATHFINDER_BRIDGE_GOES_UP_PENALTY;

   448

			}

   449

		}

   450

		if (parent_tileh == SLOPE_FLAT) res += AI_PATHFINDER_BRIDGE_GOES_UP_PENALTY;

   451

		if (tileh == SLOPE_FLAT) res += AI_PATHFINDER_BRIDGE_GOES_UP_PENALTY;

   452

	}

   453

   454

	//  To prevent the AI from taking the fastest way in tiles, but not the fastest way

   455

	//    in speed, we have to give a good penalty to direction changing

   456

	//  This way, we get almost the fastest way in tiles, and a very good speed on the track

   457

	if (!PathFinderInfo->rail_or_road) {

   458

		if (parent->path.parent != NULL &&

   459

				AiNew_GetDirection(current->tile, parent->path.node.tile) != AiNew_GetDirection(parent->path.node.tile, parent->path.parent->node.tile)) {

   460

			// When road exists, we don't like turning, but its free, so don't be to piggy about it

   461

			if (IsRoad(parent->path.node.tile)) {

   462

				res += AI_PATHFINDER_DIRECTION_CHANGE_ON_EXISTING_ROAD_PENALTY;

   463

			} else {

   464

				res += AI_PATHFINDER_DIRECTION_CHANGE_PENALTY;

   465

			}

   466

		}

   467

	} else {

   468

		// For rail we have 1 exeption: diagonal rail..

   469

		// So we fetch 2 raildirection. That of the current one, and of the one before that

   470

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

   471

			int dir1 = AiNew_GetRailDirection(parent->path.parent->node.tile, parent->path.node.tile, current->tile);

   472

			int dir2 = AiNew_GetRailDirection(parent->path.parent->parent->node.tile, parent->path.parent->node.tile, parent->path.node.tile);

   473

			// First, see if we are on diagonal path, that is better than straight path

   474

			if (dir1 > 1) res -= AI_PATHFINDER_DIAGONAL_BONUS;

   475

   476

			// First see if they are different

   477

			if (dir1 != dir2) {

   478

				// dir 2 and 3 are 1 diagonal track, and 4 and 5.

   479

				if (!(((dir1 == 2 || dir1 == 3) && (dir2 == 2 || dir2 == 3)) || ((dir1 == 4 || dir1 == 5) && (dir2 == 4 || dir2 == 5)))) {

   480

					// It is not, so we changed of direction

   481

					res += AI_PATHFINDER_DIRECTION_CHANGE_PENALTY;