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#include "stdafx.h"

     2

#include "ttd.h"

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#include "debug.h"

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#include "map.h"

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#include "tile.h"

     6

#include "command.h"

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#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

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static bool TestCanBuildStationHere(uint tile, byte dir)

    15

{

    16

    Player *p = DEREF_PLAYER(_current_player);

    17

    if (dir == TEST_STATION_NO_DIR) {

    18

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

    19

        //  should be fixed!!!

    20

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

    21

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

    22

            if (res != CMD_ERROR)

    23

            	return true;

    24

        }

    25

        return false;

    26

    } else {

    27

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

    28

        if (res == CMD_ERROR)

    29

        	return false;

    30

    }

    31

    return true;

    32

}

    33

    34

    35

static bool IsRoad(TileIndex tile)

    36

{

    37

	return

    38

		// MP_STREET, but not a road depot?

    39

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

    40

		(IsTileType(tile, MP_TUNNELBRIDGE) && (

    41

			// road tunnel?

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

    43

			// road bridge?

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

    45

		));

    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

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

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

    54

{

    55

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

    56

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

    57

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

    58

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

    59

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

    60

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

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    			return AYSTAR_FOUND_END_NODE;

    62

    63

	return AYSTAR_DONE;

    64

}

    65

    66

// Calculates the hash

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

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static uint AiPathFinder_Hash(uint key1, uint key2)

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{

    70

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

    71

}

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    73

// Clear the memory of all the things

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static void AyStar_AiPathFinder_Free(AyStar *aystar)

    75

{

    76

	AyStarMain_Free(aystar);

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	free(aystar);

    78

}

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    80

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

    81

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

    82

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

    83

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

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    85

// This creates the AiPathFinder

    86

AyStar *new_AyStar_AiPathFinder(int max_tiles_around, Ai_PathFinderInfo *PathFinderInfo) {

    87

	PathNode start_node;

    88

	uint x,y;

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	// Create AyStar

    90

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

    91

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

    92

	// Set the function pointers

    93

	result->CalculateG = AyStar_AiPathFinder_CalculateG;

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	result->CalculateH = AyStar_AiPathFinder_CalculateH;

    95

	result->EndNodeCheck = AyStar_AiPathFinder_EndNodeCheck;

    96

	result->FoundEndNode = AyStar_AiPathFinder_FoundEndNode;

    97

	result->GetNeighbours = AyStar_AiPathFinder_GetNeighbours;

    98

    99

	result->free = AyStar_AiPathFinder_Free;

   100

   101

	// Set some information

   102

	result->loops_per_tick = AI_PATHFINDER_LOOPS_PER_TICK;

   103

	result->max_path_cost = 0;

   104

	result->max_search_nodes = AI_PATHFINDER_MAX_SEARCH_NODES;

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   106

	// Set the user_data to the PathFinderInfo

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	result->user_target = PathFinderInfo;

   108

   109

	// Set the start node

   110

	start_node.parent = NULL;

   111

	start_node.node.direction = 0;

   112

	start_node.node.user_data[0] = 0;

   113

   114

	// Now we add all the starting tiles

   115

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

   116

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

   117

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

   118

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

   119

		}

   120

	}

   121

   122

	return result;

   123

}

   124

   125

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

   126

void clean_AyStar_AiPathFinder(AyStar *aystar, Ai_PathFinderInfo *PathFinderInfo) {

   127

	PathNode start_node;

   128

	uint x,y;

   129

   130

	aystar->clear(aystar);

   131

   132

	// Set the user_data to the PathFinderInfo

   133

	aystar->user_target = PathFinderInfo;

   134

   135

	// Set the start node

   136

	start_node.parent = NULL;

   137

	start_node.node.direction = 0;

   138

	start_node.node.user_data[0] = 0;

   139

	start_node.node.tile = PathFinderInfo->start_tile_tl;

   140

   141

	// Now we add all the starting tiles

   142

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

   143

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

   144

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

   145

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

   146

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

   147

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

   148

		}

   149

	}

   150

}

   151

   152

// The h-value, simple calculation

   153

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

   154

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

   155

	int r, r2;

   156

	if (PathFinderInfo->end_direction != AI_PATHFINDER_NO_DIRECTION) {

   157

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

   158

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

   159

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

   160

	} else {

   161

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

   162

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

   163

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

   164

	}

   165

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

   166

	if (r2 < r) r = r2;

   167

	return r * AI_PATHFINDER_H_MULTIPLER;

   168

}

   169

   170

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

   171

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

   172

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

   173

	uint i = 0;

   174

	PathNode *parent = &current->path;

   175

   176

	do {

   177

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

   178

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

   179

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

   180

			// We ran out of space for the PathFinder

   181

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

   182

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

   183

			return;

   184

		}

   185

		parent = parent->parent;

   186

	} while (parent != NULL);

   187

	PathFinderInfo->route_length = i;

   188

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

   189

}

   190

   191

// What tiles are around us.

   192

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

   193

		uint i;

   194

		int r;

   195

		int dir;

   196

   197

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

   198

   199

    aystar->num_neighbours = 0;

   200

   201

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

   202

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

   203

   		if (TileX(TileOffsByDir(i) + current->path.node.tile) > 1 &&

   204

					TileX(TileOffsByDir(i) + current->path.node.tile) < MapMaxX() - 1 &&

   205

       		TileY(TileOffsByDir(i) + current->path.node.tile) > 1 &&

   206

					TileY(TileOffsByDir(i) + current->path.node.tile) < MapMaxY() - 1) {

   207

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

   208

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

   209

   210

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

   211

       		if (!PathFinderInfo->rail_or_road && IsRoad(current->path.node.tile + TileOffsByDir(i))) {

   212

       			if (IsTileType(current->path.node.tile + TileOffsByDir(i), MP_TUNNELBRIDGE)) {

   213

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

   214

       				if ((_map5[current->path.node.tile + TileOffsByDir(i)] & 1U) != (i & 1)) continue;

   215

   					// This problem only is valid for tunnels:

   216

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

   217

       				if ((_map5[current->path.node.tile + TileOffsByDir(i)] & 0x80) == 0) {

   218

       					if (i != (_map5[current->path.node.tile + TileOffsByDir(i)] & 3U)) continue;

   219

       				}

   220

       			}

   221

       		}

   222

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

   223

       		if (!PathFinderInfo->rail_or_road && IsRoad(current->path.node.tile)) {

   224

       			if (IsTileType(current->path.node.tile, MP_TUNNELBRIDGE)) {

   225

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

   226

       				if ((_map5[current->path.node.tile] & 1U) != (i & 1)) continue;

   227

       			}

   228

       		}

   229

   230

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

   231

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

   232

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

   233

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

   234

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

   235

       		}

   236

       		dir = 0;

   237

   238

       		// First, check if we have a parent

   239

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

   240

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

   241

       			if (PathFinderInfo->start_direction != AI_PATHFINDER_NO_DIRECTION) {

   242

		       		// We do need a direction?

   243

		       		if (AiNew_GetDirection(current->path.node.tile, current->path.node.tile + TileOffsByDir(i)) != PathFinderInfo->start_direction)

   244

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

   245

		       			continue;

   246

		       	}

   247

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

   248

       			if (PathFinderInfo->rail_or_road) {

   249

       				// Rail check

   250

       				dir = AiNew_GetRailDirection(current->path.parent->node.tile, current->path.node.tile, current->path.node.tile + TileOffsByDir(i));

   251

       				r = DoCommandByTile(current->path.node.tile, 0, dir, DC_AUTO | DC_NO_WATER, CMD_BUILD_SINGLE_RAIL);

   252

       				if (r == CMD_ERROR) continue;

   253

#ifdef AI_PATHFINDER_NO_90DEGREES_TURN

   254

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

   255

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

   256

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

   257

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

   258

       						continue;

   259

       					}

   260

       				}

   261

#endif

   262

       			} else {

   263

       				// Road check

   264

       				dir = AiNew_GetRoadDirection(current->path.parent->node.tile, current->path.node.tile, current->path.node.tile + TileOffsByDir(i));

   265

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

   266

       					if (IsTileType(current->path.node.tile, MP_TUNNELBRIDGE)) {

   267

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

   268

       						dir = 0;

   269

       					} else {

   270

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

   271

	       					if ((_map5[current->path.node.tile] & dir) != dir) {

   272

	       						// We do miss some pieces :(

   273

	       						dir &= ~_map5[current->path.node.tile];

   274

	       					} else {

   275

	       						dir = 0;

   276

    	   					}

   277

    	   				}

   278

       				}

   279

       				// Only destruct things if it is MP_CLEAR of MP_TREES

   280

       				if (dir != 0) {

   281

       					r = DoCommandByTile(current->path.node.tile, dir, 0, DC_AUTO | DC_NO_WATER, CMD_BUILD_ROAD);

   282

       					if (r == CMD_ERROR) continue;

   283

       				}

   284

       			}

   285

   286

       		}

   287

   288

			// The tile can be connected

   289

   			aystar->neighbours[aystar->num_neighbours].tile = TileOffsByDir(i) + current->path.node.tile;

   290

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

   291

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

   292

       	}

   293

    }

   294

   295

    // Next step, check for bridges and tunnels

   296

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

   297

   298

        TileInfo ti;

   299

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

   300

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

   301

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

   302

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

   303

    	TileIndex new_tile = tile;

   304

   305

    	FindLandscapeHeightByTile(&ti, tile);

   306

   307

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

   308

   		//  And if there is a road or rail blocking

   309

   		if (ti.tileh != 0 ||

   310

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

   311

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

   312

   313

    		for (;;) {

   314

    			new_tile += TileOffsByDir(dir);

   315

   316

    	    	// Precheck, is the length allowed?

   317

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

   318

   319

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

   320

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

   321

   322

    	    	// Try building the bridge..

   323

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

   324

	    	   	if (r == CMD_ERROR) continue;

   325

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

   326

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

   327

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

   328

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

   329

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

   330

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

   331

			}

   332

    	}

   333

   334

    	// Next, check for tunnels!

   335

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

   336

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

   337

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

   338

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

   339

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

   340

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

   341

    		// Now simply check if a tunnel can be build

   342

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

   343

    		FindLandscapeHeightByTile(&ti, _build_tunnel_endtile);

   344

    		if (r != CMD_ERROR && (ti.tileh == 3 || ti.tileh == 6 || ti.tileh == 9 || ti.tileh == 12)) {

   345

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

   346

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

   347

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

   348

    		}

   349

    	}

   350

  	}

   351

}

   352

   353

extern uint GetRailFoundation(uint tileh, uint bits);

   354

extern uint GetRoadFoundation(uint tileh, uint bits);

   355

extern uint GetBridgeFoundation(uint tileh, byte direction);

   356

enum {

   357

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

   358

};

   359

   360

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

   361

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

   362

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

   363

	int r, res = 0;

   364

	TileInfo ti, parent_ti;

   365

   366

	// Gather some information about the tile..

   367

	FindLandscapeHeightByTile(&ti, current->tile);

   368

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

   369

   370

	// Check if we hit the end-tile

   371

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

   372

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

   373

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

   374

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

   375

			return AYSTAR_INVALID_NODE;

   376

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

   377

		return 0;

   378

	}

   379

   380

	// Give everything a small penalty

   381

	res += AI_PATHFINDER_PENALTY;

   382

   383

	if (!PathFinderInfo->rail_or_road) {

   384

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

   385

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

   386

		if (IsRoad(current->tile)) {

   387

			res -= AI_PATHFINDER_ROAD_ALREADY_EXISTS_BONUS;

   388

		}

   389

	}

   390

   391

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

   392

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

   393

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

   394

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

   395

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

   396

	//  from one side.

   397

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

   398

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

   399

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

   400

			if (PathFinderInfo->rail_or_road) {

   401

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

   402

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

   403

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

   404

					res += AI_PATHFINDER_TILE_GOES_UP_PENALTY;

   405

				} else {

   406

					res += AI_PATHFINDER_FOUNDATION_PENALTY;

   407

				}

   408

			} else {

   409

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

   410

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

   411

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

   412

						res += AI_PATHFINDER_TILE_GOES_UP_PENALTY;

   413

					else

   414

						res += AI_PATHFINDER_FOUNDATION_PENALTY;

   415

				}

   416

			}

   417

		}

   418

	}

   419

   420

	// Are we part of a tunnel?

   421

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

   422

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

   423

		// Ironicly, we are using BridgeCode here ;)

   424

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

   425

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

   426

	}

   427

   428

	// Are we part of a bridge?

   429

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

   430

		// That means for every length a penalty

   431

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

   432

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

   433

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

   434

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

   435

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

   436

				res += AI_PATHFINDER_BRIDGE_GOES_UP_PENALTY;

   437

		}

   438

		// Second for the end point

   439

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

   440

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

   441

				res += AI_PATHFINDER_BRIDGE_GOES_UP_PENALTY;

   442

		}

   443

		if (parent_ti.tileh == 0)

   444

			res += AI_PATHFINDER_BRIDGE_GOES_UP_PENALTY;

   445

		if (ti.tileh == 0)

   446

			res += AI_PATHFINDER_BRIDGE_GOES_UP_PENALTY;

   447

	}

   448

   449

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

   450

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

   451

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

   452

	if (!PathFinderInfo->rail_or_road) {

   453

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

   454

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

   455

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

   456

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

   457

				res += AI_PATHFINDER_DIRECTION_CHANGE_ON_EXISTING_ROAD_PENALTY;

   458

			else

   459

				res += AI_PATHFINDER_DIRECTION_CHANGE_PENALTY;

   460

		}

   461

	} else {

   462

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

   463

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

   464

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

   465

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

   466

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

   467

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

   468

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

   469

   470

			// First see if they are different

   471

			if (dir1 != dir2) {

   472

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

   473

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

   474

					// It is not, so we changed of direction

   475

					res += AI_PATHFINDER_DIRECTION_CHANGE_PENALTY;

   476

				}

   477

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

   478

					int dir3 = AiNew_GetRailDirection(parent->path.parent->parent->parent->node.tile, parent->path.parent->parent->node.tile, parent->path.parent->node.tile);

   479

					// Check if we changed 3 tiles of direction in 3 tiles.. bad!!!

   480

					if ((dir1 == 0 || dir1 == 1) && dir2 > 1 && (dir3 == 0 || dir3 == 1)) {

   481

						res += AI_PATHFINDER_CURVE_PENALTY;

   482

					}

   483

				}

   484

			}

   485

		}

   486

	}

   487

   488

	// Res should never be below zero.. if so, make it zero!