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#include "stdafx.h"

     2

#include "openttd.h"

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#include "debug.h"

     4

#include "map.h"

     5

#include "tile.h"

     6

#include "command.h"

     7

#include "ai.h"

     8

#include "depot.h"

     9

    10

#define TEST_STATION_NO_DIR 0xFF

    11

    12

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

    13

// TODO: make it train compatible

    14

static bool TestCanBuildStationHere(TileIndex tile, byte dir)

    15

{

    16

	Player *p = GetPlayer(_current_player);

    17

    18

	if (dir == TEST_STATION_NO_DIR) {

    19

		int32 ret;

    20

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

    21

		//  should be fixed!!!

    22

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

    23

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

    24

			if (!CmdFailed(ret)) return true;

    25

		}

    26

		return false;

    27

	}

    28

    29

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

    30

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

    31

}

    32

    33

    34

static bool IsRoad(TileIndex tile)

    35

{

    36

	return

    37

		// MP_STREET, but not a road depot?

    38

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

    39

		(IsTileType(tile, MP_TUNNELBRIDGE) && (

    40

			// road tunnel?

    41

			((_map5[tile] & 0x80) == 0 && (_map5[tile] & 0x4) == 0x4) ||

    42

			// road bridge?

    43

			((_map5[tile] & 0x80) != 0 && (_map5[tile] & 0x2) == 0x2)

    44

		));

    45

}

    46

    47

    48

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

    49

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

    50

    51

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

    52

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

    53

{

    54

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

    55

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

    56

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

    57

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

    58

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

    59

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

    60

				return AYSTAR_FOUND_END_NODE;

    61

    62

	return AYSTAR_DONE;

    63

}

    64

    65

// Calculates the hash

    66

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

    67

static uint AiPathFinder_Hash(uint key1, uint key2)

    68

{

    69

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

    70

}

    71

    72

// Clear the memory of all the things

    73

static void AyStar_AiPathFinder_Free(AyStar *aystar)

    74

{

    75

	AyStarMain_Free(aystar);

    76

	free(aystar);

    77

}

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    79

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

    80

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

    81

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

    82

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

    83

    84

// This creates the AiPathFinder

    85

AyStar *new_AyStar_AiPathFinder(int max_tiles_around, Ai_PathFinderInfo *PathFinderInfo)

    86

{

    87

	PathNode start_node;

    88

	uint x;

    89

	uint y;

    90

	// Create AyStar

    91

	AyStar *result = malloc(sizeof(AyStar));

    92

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

    93

	// Set the function pointers

    94

	result->CalculateG = AyStar_AiPathFinder_CalculateG;

    95

	result->CalculateH = AyStar_AiPathFinder_CalculateH;

    96

	result->EndNodeCheck = AyStar_AiPathFinder_EndNodeCheck;

    97

	result->FoundEndNode = AyStar_AiPathFinder_FoundEndNode;

    98

	result->GetNeighbours = AyStar_AiPathFinder_GetNeighbours;

    99

   102

	result->free = AyStar_AiPathFinder_Free;

   103

   104

	// Set some information

   105

	result->loops_per_tick = AI_PATHFINDER_LOOPS_PER_TICK;

   106

	result->max_path_cost = 0;

   107

	result->max_search_nodes = AI_PATHFINDER_MAX_SEARCH_NODES;

   108

   109

	// Set the user_data to the PathFinderInfo

   110

	result->user_target = PathFinderInfo;

   111

   112

	// Set the start node

   113

	start_node.parent = NULL;

   114

	start_node.node.direction = 0;

   115

	start_node.node.user_data[0] = 0;

   116

   117

	// Now we add all the starting tiles

   118

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

   119

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

   120

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

   121

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

   122

		}

   123

	}

   124

   125

	return result;

   126

}

   127

   128

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

   129

void clean_AyStar_AiPathFinder(AyStar *aystar, Ai_PathFinderInfo *PathFinderInfo)

   130

{

   131

	PathNode start_node;

   132

	uint x;

   133

	uint y;

   134

   135

	aystar->clear(aystar);

   136

   137

	// Set the user_data to the PathFinderInfo

   138

	aystar->user_target = PathFinderInfo;

   139

   140

	// Set the start node

   141

	start_node.parent = NULL;

   142

	start_node.node.direction = 0;

   143

	start_node.node.user_data[0] = 0;

   144

	start_node.node.tile = PathFinderInfo->start_tile_tl;

   145

   146

	// Now we add all the starting tiles

   147

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

   148

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

   149

			if (!(IsTileType(TileXY(x, y), MP_CLEAR) || IsTileType(TileXY(x, y), MP_TREES))) continue;

   150

			if (!TestCanBuildStationHere(TileXY(x, y), TEST_STATION_NO_DIR)) continue;

   151

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

   152

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

   153

		}

   154

	}

   155

}

   156

   157

// The h-value, simple calculation

   158

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

   159

{

   160

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

   161

	int r, r2;

   162

	if (PathFinderInfo->end_direction != AI_PATHFINDER_NO_DIRECTION) {

   163

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

   164

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

   165

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

   166

	} else {

   167

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

   168

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

   169

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

   170

	}

   171

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

   172

	if (r2 < r) r = r2;

   173

	return r * AI_PATHFINDER_H_MULTIPLER;

   174

}

   175

   176

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

   177

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

   178

{

   179

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

   180

	uint i = 0;

   181

	PathNode *parent = &current->path;

   182

   183

	do {

   184

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

   185

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

   186

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

   187

			// We ran out of space for the PathFinder

   188

			DEBUG(ai, 0)("[AiPathFinder] Ran out of space in the route[] array!!!");

   189

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

   190

			return;

   191

		}

   192

		parent = parent->parent;

   193

	} while (parent != NULL);

   194

	PathFinderInfo->route_length = i;

   195

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

   196

}

   197

   198

// What tiles are around us.

   199

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

   200

{

   201

	uint i;

   202

	int ret;

   203

	int dir;

   204

   205

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

   206

   207

	aystar->num_neighbours = 0;

   208

   209

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

   210

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

   211

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

   212

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

   213

   214

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

   215

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

   216

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

   217

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

   218

   219

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

   220

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

   221

				if (IsTileType(atile, MP_TUNNELBRIDGE)) {

   222

					// An existing bridge... let's test the direction ;)

   223

					if ((_map5[atile] & 1U) != (i & 1)) continue;

   224

					// This problem only is valid for tunnels:

   225

					// When the last tile was not yet a tunnel, check if we enter from the right side..

   226

					if ((_map5[atile] & 0x80) == 0) {

   227

						if (i != (_map5[atile] & 3U)) continue;

   228

					}

   229

				}

   230

			}

   231

			// But also if we are on a bridge, we can only move a certain direction

   232

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

   233

				if (IsTileType(ctile, MP_TUNNELBRIDGE)) {

   234

					// An existing bridge/tunnel... let's test the direction ;)

   235

					if ((_map5[ctile] & 1U) != (i & 1)) continue;

   236

				}

   237

			}

   238

   239

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

   240

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

   241

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

   242

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

   243

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

   244

			}

   245

			dir = 0;

   246

   247

			// First, check if we have a parent

   248

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

   249

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

   250

				if (PathFinderInfo->start_direction != AI_PATHFINDER_NO_DIRECTION) {

   251

					// We do need a direction?

   252

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

   253

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

   254

						continue;

   255

					}

   256

				}

   257

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

   258

				if (PathFinderInfo->rail_or_road) {

   259

					// Rail check

   260

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

   261

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

   262

					if (CmdFailed(ret)) continue;

   263

#ifdef AI_PATHFINDER_NO_90DEGREES_TURN

   264

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

   265

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

   266

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

   267

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

   268

							continue;

   269

						}

   270

					}

   271

#endif

   272

				} else {

   273

					// Road check

   274

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

   275

					if (IsRoad(ctile)) {

   276

						if (IsTileType(ctile, MP_TUNNELBRIDGE)) {

   277

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

   278

							dir = 0;

   279

						} else {

   280

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

   281

							if ((_map5[ctile] & dir) != dir) {

   282

								// We do miss some pieces :(

   283

								dir &= ~_map5[ctile];

   284

							} else {

   285

								dir = 0;

   286

							}

   287

						}

   288

					}

   289

					// Only destruct things if it is MP_CLEAR of MP_TREES

   290

					if (dir != 0) {

   291

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

   292

						if (CmdFailed(ret)) continue;

   293

					}

   294

				}

   295

			}

   296

   297

			// The tile can be connected

   298

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

   299

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

   300

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

   301

		}

   302

	}

   303

   304

	// Next step, check for bridges and tunnels

   305

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

   306

		TileInfo ti;

   307

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

   308

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

   309

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

   310

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

   311

		TileIndex new_tile = tile;

   312

   313

		FindLandscapeHeightByTile(&ti, tile);

   314

   315

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

   316

		//  And if there is a road or rail blocking

   317

		if (ti.tileh != 0 ||

   318

				(PathFinderInfo->rail_or_road && IsTileType(tile + TileOffsByDir(dir), MP_STREET)) ||

   319

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

   320

   321

			for (;;) {

   322

				new_tile += TileOffsByDir(dir);

   323

   324

				// Precheck, is the length allowed?

   325

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

   326

   327

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

   328

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

   329

   330

				// Try building the bridge..

   331

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

   332

				if (CmdFailed(ret)) continue;

   333

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

   334

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

   335

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

   336

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

   337

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

   338

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

   339

			}

   340

		}

   341

   342

		// Next, check for tunnels!

   343

		// Tunnels can only be build with tileh of 3, 6, 9 or 12, depending on the direction

   344

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

   345

		if ((dir == 0 && ti.tileh == 12) ||

   346

				(dir == 1 && ti.tileh == 6) ||

   347

				(dir == 2 && ti.tileh == 3) ||

   348

				(dir == 3 && ti.tileh == 9)) {

   349

			// Now simply check if a tunnel can be build

   350

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

   351

			FindLandscapeHeightByTile(&ti, _build_tunnel_endtile);

   352

			if (!CmdFailed(ret) && (ti.tileh == 3 || ti.tileh == 6 || ti.tileh == 9 || ti.tileh == 12)) {

   353

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

   354

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

   355

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

   356

			}

   357

		}

   358

	}

   359

}

   360

   361

extern uint GetRailFoundation(uint tileh, uint bits);

   362

extern uint GetRoadFoundation(uint tileh, uint bits);

   363

extern uint GetBridgeFoundation(uint tileh, byte direction);

   364

enum {

   365

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

   366

};

   367

   368

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

   369

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

   370

{

   371

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

   372

	int r, res = 0;

   373

	TileInfo ti, parent_ti;

   374

   375

	// Gather some information about the tile..

   376

	FindLandscapeHeightByTile(&ti, current->tile);

   377

	FindLandscapeHeightByTile(&parent_ti, parent->path.node.tile);

   378

   379

	// Check if we hit the end-tile

   380

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

   381

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

   382

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

   383

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

   384

			return AYSTAR_INVALID_NODE;

   385

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

   386

		return 0;

   387

	}

   388

   389

	// Give everything a small penalty

   390

	res += AI_PATHFINDER_PENALTY;

   391

   392

	if (!PathFinderInfo->rail_or_road) {

   393

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

   394

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

   395

		if (IsRoad(current->tile)) {

   396

			res -= AI_PATHFINDER_ROAD_ALREADY_EXISTS_BONUS;

   397

		}

   398

	}

   399

   400

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

   401

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

   402

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

   403

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

   404

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

   405

	//  from one side.

   406

	if (parent_ti.tileh != 0 && parent->path.parent != NULL) {

   407

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

   408

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

   409

			if (PathFinderInfo->rail_or_road) {

   410

				r = GetRailFoundation(parent_ti.tileh, 1 << AiNew_GetRailDirection(parent->path.parent->node.tile, parent->path.node.tile, current->tile));

   411

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

   412

				if (r >= 15 || (r == 0 && (BRIDGE_NO_FOUNDATION & (1 << ti.tileh)))) {

   413

					res += AI_PATHFINDER_TILE_GOES_UP_PENALTY;

   414

				} else {

   415

					res += AI_PATHFINDER_FOUNDATION_PENALTY;

   416

				}

   417

			} else {

   418

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

   419

					r = GetRoadFoundation(parent_ti.tileh, AiNew_GetRoadDirection(parent->path.parent->node.tile, parent->path.node.tile, current->tile));

   420

					if (r >= 15 || r == 0)

   421

						res += AI_PATHFINDER_TILE_GOES_UP_PENALTY;

   422

					else

   423

						res += AI_PATHFINDER_FOUNDATION_PENALTY;

   424

				}

   425

			}

   426

		}

   427

	}

   428

   429

	// Are we part of a tunnel?

   430

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

   431

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

   432

		// Ironicly, we are using BridgeCode here ;)

   433

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

   434

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

   435

	}

   436

   437

	// Are we part of a bridge?

   438

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

   439

		// That means for every length a penalty

   440

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

   441

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

   442

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

   443

		if (!(BRIDGE_NO_FOUNDATION & (1 << parent_ti.tileh))) {

   444

			if (GetBridgeFoundation(parent_ti.tileh, (current->user_data[0] >> 8) & 1) < 15)

   445

				res += AI_PATHFINDER_BRIDGE_GOES_UP_PENALTY;

   446

		}

   447

		// Second for the end point

   448

		if (!(BRIDGE_NO_FOUNDATION & (1 << ti.tileh))) {

   449

			if (GetBridgeFoundation(ti.tileh, (current->user_data[0] >> 8) & 1) < 15)

   450

				res += AI_PATHFINDER_BRIDGE_GOES_UP_PENALTY;

   451

		}

   452

		if (parent_ti.tileh == 0)

   453

			res += AI_PATHFINDER_BRIDGE_GOES_UP_PENALTY;

   454

		if (ti.tileh == 0)

   455

			res += AI_PATHFINDER_BRIDGE_GOES_UP_PENALTY;

   456

	}

   457

   458

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

   459

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

   460

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

   461

	if (!PathFinderInfo->rail_or_road) {

   462

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

   463

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

   464

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

   465

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

   466

				res += AI_PATHFINDER_DIRECTION_CHANGE_ON_EXISTING_ROAD_PENALTY;

   467

			else

   468

				res += AI_PATHFINDER_DIRECTION_CHANGE_PENALTY;

   469

		}

   470

	} else {

   471

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

   472

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

   473

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

   474

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

   475

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

   476

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

   477

			if (dir1 > 1) { res -= AI_PATHFINDER_DIAGONAL_BONUS; }

   478

   479

			// First see if they are different

   480

			if (dir1 != dir2) {

   481

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

   482

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

   483

					// It is not, so we changed of direction

   484

					res += AI_PATHFINDER_DIRECTION_CHANGE_PENALTY;

   485

				}

   486

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