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/*
Minetest
Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/

#include "mapsector.h"
#include "jmutexautolock.h"
#ifndef SERVER
#include "client.h"
#endif
#include "exceptions.h"
#include "mapblock.h"

MapSector::MapSector(Map *parent, v2s16 pos, IGameDef *gamedef):
		differs_from_disk(false),
		m_parent(parent),
		m_pos(pos),
		m_gamedef(gamedef),
		m_block_cache(NULL)
{
}

MapSector::~MapSector()
{
	deleteBlocks();
}

void MapSector::deleteBlocks()
{
	// Clear cache
	m_block_cache = NULL;

	// Delete all
	for(std::map<s16, MapBlock*>::iterator i = m_blocks.begin();
		i != m_blocks.end(); ++i)
	{
		delete i->second;
	}

	// Clear container
	m_blocks.clear();
}

MapBlock * MapSector::getBlockBuffered(s16 y)
{
	MapBlock *block;

	if(m_block_cache != NULL && y == m_block_cache_y){
		return m_block_cache;
	}
	
	// If block doesn't exist, return NULL
	std::map<s16, MapBlock*>::iterator n = m_blocks.find(y);
	if(n == m_blocks.end())
	{
		block = NULL;
	}
	// If block exists, return it
	else{
		block = n->second;
	}
	
	// Cache the last result
	m_block_cache_y = y;
	m_block_cache = block;
	
	return block;
}

MapBlock * MapSector::getBlockNoCreateNoEx(s16 y)
{
	return getBlockBuffered(y);
}

MapBlock * MapSector::createBlankBlockNoInsert(s16 y)
{
	assert(getBlockBuffered(y) == NULL);

	v3s16 blockpos_map(m_pos.X, y, m_pos.Y);
	
	MapBlock *block = new MapBlock(m_parent, blockpos_map, m_gamedef);
	
	return block;
}

MapBlock * MapSector::createBlankBlock(s16 y)
{
	MapBlock *block = createBlankBlockNoInsert(y);
	
	m_blocks[y] = block;

	return block;
}

void MapSector::insertBlock(MapBlock *block)
{
	s16 block_y = block->getPos().Y;

	MapBlock *block2 = getBlockBuffered(block_y);
	if(block2 != NULL){
		throw AlreadyExistsException("Block already exists");
	}

	v2s16 p2d(block->getPos().X, block->getPos().Z);
	assert(p2d == m_pos);
	
	// Insert into container
	m_blocks[block_y] = block;
}

void MapSector::deleteBlock(MapBlock *block)
{
	s16 block_y = block->getPos().Y;

	// Clear from cache
	m_block_cache = NULL;
	
	// Remove from container
	m_blocks.erase(block_y);

	// Delete
	delete block;
}

void MapSector::getBlocks(std::list<MapBlock*> &dest)
{
	for(std::map<s16, MapBlock*>::iterator bi = m_blocks.begin();
		bi != m_blocks.end(); ++bi)
	{
		dest.push_back(bi->second);
	}
}

/*
	ServerMapSector
*/

ServerMapSector::ServerMapSector(Map *parent, v2s16 pos, IGameDef *gamedef):
		MapSector(parent, pos, gamedef)
{
}

ServerMapSector::~ServerMapSector()
{
}

void ServerMapSector::serialize(std::ostream &os, u8 version)
{
	if(!ser_ver_supported(version))
		throw VersionMismatchException("ERROR: MapSector format not supported");
	
	/*
		[0] u8 serialization version
		+ heightmap data
	*/
	
	// Server has both of these, no need to support not having them.
	//assert(m_objects != NULL);

	// Write version
	os.write((char*)&version, 1);
	
	/*
		Add stuff here, if needed
	*/

}

ServerMapSector* ServerMapSector::deSerialize(
		std::istream &is,
		Map *parent,
		v2s16 p2d,
		std::map<v2s16, MapSector*> & sectors,
		IGameDef *gamedef
	)
{
	/*
		[0] u8 serialization version
		+ heightmap data
	*/

	/*
		Read stuff
	*/
	
	// Read version
	u8 version = SER_FMT_VER_INVALID;
	is.read((char*)&version, 1);
	
	if(!ser_ver_supported(version))
		throw VersionMismatchException("ERROR: MapSector format not supported");
	
	/*
		Add necessary reading stuff here
	*/
	
	/*
		Get or create sector
	*/

	ServerMapSector *sector = NULL;

	std::map<v2s16, MapSector*>::iterator n = sectors.find(p2d);

	if(n != sectors.end())
	{
		dstream<<"WARNING: deSerializing existent sectors not supported "
				"at the moment, because code hasn't been tested."
				<<std::endl;

		MapSector *sector = n->second;
		assert(sector->getId() == MAPSECTOR_SERVER);
		return (ServerMapSector*)sector;
	}
	else
	{
		sector = new ServerMapSector(parent, p2d, gamedef);
		sectors[p2d] = sector;
	}

	/*
		Set stuff in sector
	*/

	// Nothing here

	return sector;
}

#ifndef SERVER
/*
	ClientMapSector
*/

ClientMapSector::ClientMapSector(Map *parent, v2s16 pos, IGameDef *gamedef):
		MapSector(parent, pos, gamedef)
{
}

ClientMapSector::~ClientMapSector()
{
}

#endif // !SERVER

//END
f='#n863'>863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411
/*
Minetest
Copyright (C) 2013 sapier, sapier at gmx dot net
Copyright (C) 2016 est31, <MTest31@outlook.com>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/

/******************************************************************************/
/* Includes                                                                   */
/******************************************************************************/

#include "pathfinder.h"
#include "serverenvironment.h"
#include "server.h"
#include "nodedef.h"

//#define PATHFINDER_DEBUG
//#define PATHFINDER_CALC_TIME

#ifdef PATHFINDER_DEBUG
	#include <string>
#endif
#ifdef PATHFINDER_DEBUG
	#include <iomanip>
#endif
#ifdef PATHFINDER_CALC_TIME
	#include <sys/time.h>
#endif

/******************************************************************************/
/* Typedefs and macros                                                        */
/******************************************************************************/

#define LVL "(" << level << ")" <<

#ifdef PATHFINDER_DEBUG
#define DEBUG_OUT(a)     std::cout << a
#define INFO_TARGET      std::cout
#define VERBOSE_TARGET   std::cout
#define ERROR_TARGET     std::cout
#else
#define DEBUG_OUT(a)     while(0)
#define INFO_TARGET      infostream << "Pathfinder: "
#define VERBOSE_TARGET   verbosestream << "Pathfinder: "
#define ERROR_TARGET     errorstream << "Pathfinder: "
#endif

/******************************************************************************/
/* Class definitions                                                          */
/******************************************************************************/


/** representation of cost in specific direction */
class PathCost {
public:

	/** default constructor */
	PathCost();

	/** copy constructor */
	PathCost(const PathCost &b);

	/** assignment operator */
	PathCost &operator= (const PathCost &b);

	bool valid;              /**< movement is possible         */
	int  value;              /**< cost of movement             */
	int  direction;          /**< y-direction of movement      */
	bool updated;            /**< this cost has ben calculated */

};


/** representation of a mapnode to be used for pathfinding */
class PathGridnode {

public:
	/** default constructor */
	PathGridnode();

	/** copy constructor */
	PathGridnode(const PathGridnode &b);

	/**
	 * assignment operator
	 * @param b node to copy
	 */
	PathGridnode &operator= (const PathGridnode &b);

	/**
	 * read cost in a specific direction
	 * @param dir direction of cost to fetch
	 */
	PathCost getCost(v3s16 dir);

	/**
	 * set cost value for movement
	 * @param dir direction to set cost for
	 * @cost cost to set
	 */
	void      setCost(v3s16 dir, PathCost cost);

	bool      valid;               /**< node is on surface                    */
	bool      target;              /**< node is target position               */
	bool      source;              /**< node is stating position              */
	int       totalcost;           /**< cost to move here from starting point */
	v3s16     sourcedir;           /**< origin of movement for current cost   */
	v3s16     pos;                 /**< real position of node                 */
	PathCost directions[4];        /**< cost in different directions          */

	/* debug values */
	bool      is_element;          /**< node is element of path detected      */
	char      type;                /**< type of node                          */
};

class Pathfinder;

/** Abstract class to manage the map data */
class GridNodeContainer {
public:
	virtual PathGridnode &access(v3s16 p)=0;
	virtual ~GridNodeContainer() {}
protected:
	Pathfinder *m_pathf;

	void initNode(v3s16 ipos, PathGridnode *p_node);
};

class ArrayGridNodeContainer : public GridNodeContainer {
public:
	virtual ~ArrayGridNodeContainer() {}
	ArrayGridNodeContainer(Pathfinder *pathf, v3s16 dimensions);
	virtual PathGridnode &access(v3s16 p);
private:
	v3s16 m_dimensions;

	int m_x_stride;
	int m_y_stride;
	std::vector<PathGridnode> m_nodes_array;
};

class MapGridNodeContainer : public GridNodeContainer {
public:
	virtual ~MapGridNodeContainer() {}
	MapGridNodeContainer(Pathfinder *pathf);
	virtual PathGridnode &access(v3s16 p);
private:
	std::map<v3s16, PathGridnode> m_nodes;
};

/** class doing pathfinding */
class Pathfinder {

public:
	/**
	 * default constructor
	 */
	Pathfinder();

	~Pathfinder();

	/**
	 * path evaluation function
	 * @param env environment to look for path
	 * @param source origin of path
	 * @param destination end position of path
	 * @param searchdistance maximum number of nodes to look in each direction
	 * @param max_jump maximum number of blocks a path may jump up
	 * @param max_drop maximum number of blocks a path may drop
	 * @param algo Algorithm to use for finding a path
	 */
	std::vector<v3s16> getPath(ServerEnvironment *env,
			v3s16 source,
			v3s16 destination,
			unsigned int searchdistance,
			unsigned int max_jump,
			unsigned int max_drop,
			PathAlgorithm algo);

private:
	/* helper functions */

	/**
	 * transform index pos to mappos
	 * @param ipos a index position
	 * @return map position
	 */
	v3s16          getRealPos(v3s16 ipos);

	/**
	 * transform mappos to index pos
	 * @param pos a real pos
	 * @return index position
	 */
	v3s16          getIndexPos(v3s16 pos);

	/**
	 * get gridnode at a specific index position
	 * @param ipos index position
	 * @return gridnode for index
	 */
	PathGridnode &getIndexElement(v3s16 ipos);

	/**
	 * Get gridnode at a specific index position
	 * @return gridnode for index
	 */
	PathGridnode &getIdxElem(s16 x, s16 y, s16 z);

	/**
	 * invert a 3d position
	 * @param pos 3d position
	 * @return pos *-1
	 */
	v3s16          invert(v3s16 pos);

	/**
	 * check if a index is within current search area
	 * @param index position to validate
	 * @return true/false
	 */
	bool           isValidIndex(v3s16 index);

	/**
	 * translate position to float position
	 * @param pos integer position
	 * @return float position
	 */
	v3f            tov3f(v3s16 pos);


	/* algorithm functions */

	/**
	 * calculate 2d manahttan distance to target on the xz plane
	 * @param pos position to calc distance
	 * @return integer distance
	 */
	int           getXZManhattanDist(v3s16 pos);

	/**
	 * get best direction based uppon heuristics
	 * @param directions list of unchecked directions
	 * @param g_pos mapnode to start from
	 * @return direction to check
	 */
	v3s16         getDirHeuristic(std::vector<v3s16> &directions, PathGridnode &g_pos);

	/**
	 * build internal data representation of search area
	 * @return true/false if costmap creation was successfull
	 */
	bool          buildCostmap();

	/**
	 * calculate cost of movement
	 * @param pos real world position to start movement
	 * @param dir direction to move to
	 * @return cost information
	 */
	PathCost     calcCost(v3s16 pos, v3s16 dir);

	/**
	 * recursive update whole search areas total cost information
	 * @param ipos position to check next
	 * @param srcdir positionc checked last time
	 * @param total_cost cost of moving to ipos
	 * @param level current recursion depth
	 * @return true/false path to destination has been found
	 */
	bool          updateAllCosts(v3s16 ipos, v3s16 srcdir, int total_cost, int level);

	/**
	 * recursive try to find a patrh to destionation
	 * @param ipos position to check next
	 * @param srcdir positionc checked last time
	 * @param total_cost cost of moving to ipos
	 * @param level current recursion depth
	 * @return true/false path to destination has been found
	 */
	bool          updateCostHeuristic(v3s16 ipos, v3s16 srcdir, int current_cost, int level);

	/**
	 * recursive build a vector containing all nodes from source to destination
	 * @param path vector to add nodes to
	 * @param pos pos to check next
	 * @param level recursion depth
	 */
	void          buildPath(std::vector<v3s16> &path, v3s16 pos, int level);

	/* variables */
	int m_max_index_x;            /**< max index of search area in x direction  */
	int m_max_index_y;            /**< max index of search area in y direction  */
	int m_max_index_z;            /**< max index of search area in z direction  */


	int m_searchdistance;         /**< max distance to search in each direction */
	int m_maxdrop;                /**< maximum number of blocks a path may drop */
	int m_maxjump;                /**< maximum number of blocks a path may jump */
	int m_min_target_distance;    /**< current smalest path to target           */

	bool m_prefetch;              /**< prefetch cost data                       */

	v3s16 m_start;                /**< source position                          */
	v3s16 m_destination;          /**< destination position                     */

	core::aabbox3d<s16> m_limits; /**< position limits in real map coordinates  */

	/** contains all map data already collected and analyzed.
		Access it via the getIndexElement/getIdxElem methods. */
	friend class GridNodeContainer;
	GridNodeContainer *m_nodes_container;

	ServerEnvironment *m_env;     /**< minetest environment pointer             */

#ifdef PATHFINDER_DEBUG

	/**
	 * print collected cost information
	 */
	void printCost();

	/**
	 * print collected cost information in a specific direction
	 * @param dir direction to print
	 */
	void printCost(PathDirections dir);

	/**
	 * print type of node as evaluated
	 */
	void printType();

	/**
	 * print pathlenght for all nodes in search area
	 */
	void printPathLen();

	/**
	 * print a path
	 * @param path path to show
	 */
	void printPath(std::vector<v3s16> path);

	/**
	 * print y direction for all movements
	 */
	void printYdir();

	/**
	 * print y direction for moving in a specific direction
	 * @param dir direction to show data
	 */
	void printYdir(PathDirections dir);

	/**
	 * helper function to translate a direction to speaking text
	 * @param dir direction to translate
	 * @return textual name of direction
	 */
	std::string dirToName(PathDirections dir);
#endif
};

/******************************************************************************/
/* implementation                                                             */
/******************************************************************************/

std::vector<v3s16> get_path(ServerEnvironment* env,
							v3s16 source,
							v3s16 destination,
							unsigned int searchdistance,
							unsigned int max_jump,
							unsigned int max_drop,
							PathAlgorithm algo)
{
	Pathfinder searchclass;

	return searchclass.getPath(env,
				source, destination,
				searchdistance, max_jump, max_drop, algo);
}

/******************************************************************************/
PathCost::PathCost()
:	valid(false),
	value(0),
	direction(0),
	updated(false)
{
	//intentionaly empty
}

/******************************************************************************/
PathCost::PathCost(const PathCost &b)
{
	valid     = b.valid;
	direction = b.direction;
	value     = b.value;
	updated   = b.updated;
}

/******************************************************************************/
PathCost &PathCost::operator= (const PathCost &b)
{
	valid     = b.valid;
	direction = b.direction;
	value     = b.value;
	updated   = b.updated;

	return *this;
}

/******************************************************************************/
PathGridnode::PathGridnode()
:	valid(false),
	target(false),
	source(false),
	totalcost(-1),
	sourcedir(v3s16(0, 0, 0)),
	pos(v3s16(0, 0, 0)),
	is_element(false),
	type('u')
{
	//intentionaly empty
}

/******************************************************************************/
PathGridnode::PathGridnode(const PathGridnode &b)
:	valid(b.valid),
	target(b.target),
	source(b.source),
	totalcost(b.totalcost),
	sourcedir(b.sourcedir),
	pos(b.pos),
	is_element(b.is_element),
	type(b.type)
{

	directions[DIR_XP] = b.directions[DIR_XP];
	directions[DIR_XM] = b.directions[DIR_XM];
	directions[DIR_ZP] = b.directions[DIR_ZP];
	directions[DIR_ZM] = b.directions[DIR_ZM];
}

/******************************************************************************/
PathGridnode &PathGridnode::operator= (const PathGridnode &b)
{
	valid      = b.valid;
	target     = b.target;
	source     = b.source;
	is_element = b.is_element;
	totalcost  = b.totalcost;
	sourcedir  = b.sourcedir;
	pos        = b.pos;
	type       = b.type;

	directions[DIR_XP] = b.directions[DIR_XP];
	directions[DIR_XM] = b.directions[DIR_XM];
	directions[DIR_ZP] = b.directions[DIR_ZP];
	directions[DIR_ZM] = b.directions[DIR_ZM];

	return *this;
}

/******************************************************************************/
PathCost PathGridnode::getCost(v3s16 dir)
{
	if (dir.X > 0) {
		return directions[DIR_XP];
	}
	if (dir.X < 0) {
		return directions[DIR_XM];
	}
	if (dir.Z > 0) {
		return directions[DIR_ZP];
	}
	if (dir.Z < 0) {
		return directions[DIR_ZM];
	}
	PathCost retval;
	return retval;
}

/******************************************************************************/
void PathGridnode::setCost(v3s16 dir, PathCost cost)
{
	if (dir.X > 0) {
		directions[DIR_XP] = cost;
	}
	if (dir.X < 0) {
		directions[DIR_XM] = cost;
	}
	if (dir.Z > 0) {
		directions[DIR_ZP] = cost;
	}
	if (dir.Z < 0) {
		directions[DIR_ZM] = cost;
	}
}

void GridNodeContainer::initNode(v3s16 ipos, PathGridnode *p_node)
{
	INodeDefManager *ndef = m_pathf->m_env->getGameDef()->ndef();
	PathGridnode &elem = *p_node;

	v3s16 realpos = m_pathf->getRealPos(ipos);

	MapNode current = m_pathf->m_env->getMap().getNodeNoEx(realpos);
	MapNode below   = m_pathf->m_env->getMap().getNodeNoEx(realpos + v3s16(0, -1, 0));


	if ((current.param0 == CONTENT_IGNORE) ||
			(below.param0 == CONTENT_IGNORE)) {
		DEBUG_OUT("Pathfinder: " << PP(realpos) <<
			" current or below is invalid element" << std::endl);
		if (current.param0 == CONTENT_IGNORE) {
			elem.type = 'i';
			DEBUG_OUT(PP(ipos) << ": " << 'i' << std::endl);
		}
		return;
	}

	//don't add anything if it isn't an air node
	if (ndef->get(current).walkable || !ndef->get(below).walkable) {
			DEBUG_OUT("Pathfinder: " << PP(realpos)
				<< " not on surface" << std::endl);
			if (ndef->get(current).walkable) {
				elem.type = 's';
				DEBUG_OUT(PP(ipos) << ": " << 's' << std::endl);
			} else {
				elem.type = '-';
				DEBUG_OUT(PP(ipos) << ": " << '-' << std::endl);
			}
			return;
	}

	elem.valid = true;
	elem.pos   = realpos;
	elem.type  = 'g';
	DEBUG_OUT(PP(ipos) << ": " << 'a' << std::endl);

	if (m_pathf->m_prefetch) {
		elem.directions[DIR_XP] = m_pathf->calcCost(realpos, v3s16( 1, 0, 0));
		elem.directions[DIR_XM] = m_pathf->calcCost(realpos, v3s16(-1, 0, 0));
		elem.directions[DIR_ZP] = m_pathf->calcCost(realpos, v3s16( 0, 0, 1));
		elem.directions[DIR_ZM] = m_pathf->calcCost(realpos, v3s16( 0, 0,-1));
	}
}

ArrayGridNodeContainer::ArrayGridNodeContainer(Pathfinder *pathf, v3s16 dimensions) :
	m_x_stride(dimensions.Y * dimensions.Z),
	m_y_stride(dimensions.Z)
{
	m_pathf = pathf;

	m_nodes_array.resize(dimensions.X * dimensions.Y * dimensions.Z);
	INFO_TARGET << "Pathfinder ArrayGridNodeContainer constructor." << std::endl;
	for (int x = 0; x < dimensions.X; x++) {
		for (int y = 0; y < dimensions.Y; y++) {
			for (int z= 0; z < dimensions.Z; z++) {
				v3s16 ipos(x, y, z);