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	Advtrains mod for minetest.	orwell

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path: root/advtrains/trainlogic.lua

	Commit message (Collapse)	Author	Age
*	Make "Can't restore train" a log message instead of atwarn()	orwell96	2019-01-22
|
*	Warn when something clears the path winthin train step	orwell96	2019-01-22
|
*	Revert "Correct last commit"	orwell96	2019-01-22
| | | |	This reverts commit 5f290819cdb78303396f9f89907ebbc66a9d74b3.
*	Revert "Debugging code to trace down path_invalidate within callbacks error"	orwell96	2019-01-22
| | | |	This reverts commit 1965e846b6c61958063ea13e2ac88ae18b701d09.
*	Revert "Index NaN check (tracking obscure error detected on LW migration)"	orwell96	2019-01-22
| | | |	This reverts commit e915b61da6f18efa49b6afacb7e9ca181d59cc5c.
*	Correct last commit	orwell96	2019-01-22
|
*	Debugging code to trace down path_invalidate within callbacks error	orwell96	2019-01-22
|
*	Workaround	orwell96	2019-01-21
|
*	Do not run train steps when path has been deleted	orwell96	2019-01-21
|
*	Avoid division through zero in get_acceleration	orwell96	2019-01-21
|
*	Index NaN check (tracking obscure error detected on LW migration)	orwell96	2019-01-21
|
*	Fix player_to_train_mapping (H#74)	orwell96	2018-12-16
| | | |	Entries were not inserted, thus neither damage protection nor teleport-to-train did work
*	Fix crashes:	orwell96	2018-12-10
| | | | |	1. when train hit a route, nil access to already cancelled route caused crash 2. fix crash when trying to ensure_init a train that doesn't exist
*	Shunt signals (not exactly Ks), along with fixes in other components that ↵	orwell96	2018-12-08
| | | |	those rely on
*	Apply speed restriction 0.5 indexes later, do not cap tarvelocity by ↵	orwell96	2018-12-04
| | | |	speed_restriction
*	Remove superfluous "tarvelocity" assignments	orwell96	2018-11-20
|
*	Remove "couple locks" and apply protection to the actual coupling process, ↵	orwell96	2018-11-10
| | | |	and fix permissions on that
*	Document fix 0a982b6356b2f4b6a28e74f9f90c4f584169a96d	orwell96	2018-10-29
| | | |	Add comment that explains why fix was necessary
*	Actually set last_connid to 1, to prevent warning	orwell96	2018-10-29
|
*	Handle the case that a train is not initialized (train_ensure_init returns ↵	orwell96	2018-10-29
| | | | | |	nil/false) Fixes H#72
*	Small fixes which do not have any effect	orwell96	2018-10-29
|
*	Improve ATC-LZB-User control interaction, smoothen LZB control operations	orwell96	2018-10-17
| | | |	(prevent flickering view when atc battles against lzb)
*	Address H#60, H#17, M#18 and M#7	orwell96	2018-10-17
| | | | | | |	duplicate "message" to "msg" make operation panel "cracky" remove inexistent dtime_s parameter add bones:bones to the list of not_blocking_trains nodes
*	Properly handle speed restrictions	orwell96	2018-10-10
|
*	Remote Routesetting from Onboard Computer	orwell96	2018-10-10
| | | |	+ Fix lzb oncoming item deletion/speed restriction
*	Properly implement invalidate_all_paths, recheck lzb on aspect change	orwell96	2018-10-10
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*	Add signal safety control override, restructure control system	orwell96	2018-10-10
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*	Teleport player to their train every 2 seconds instead of just on_joinplayer	orwell96	2018-08-12
| | | |	Solves problem of wagon being unloaded while player sitting inside it because of network lag
*	Fix some incompatibility crash for old worlds	orwell96	2018-08-12
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*	Fix ATC rail reversing	orwell96	2018-08-12
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*	Add off-track train flag, fixes wagon object property reset on reversing	orwell96	2018-07-04
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*	Implement trains blocking sections	orwell96	2018-06-29
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*	Fix final bugs and to-do's (u.a.save/load system)	orwell96	2018-06-14
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*	Mainly make collisions and coupling work	orwell96	2018-06-14
| | | |	Missing: ATC stuff, yaw problems
*	Implement collisions. (does not work yet, still code errors)	orwell96	2018-06-14
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*	Implement a reverse path lookup for trains instead of an occupations window ↵	orwell96	2018-06-14
| | | |	system
*	Fix path_dir to actually be an angle, path item deletion and orientation of ↵	orwell96	2018-06-14
| | | | | | | |	wagons The occupation system as it is now will change. For each position, I will save the index in the train's path, and implement a callback system. I need this because the occupation window system will not be enough to cover all use cases (e.g. to make a train stop with it's center or back at a certain position, I need 3 different brake distances, which doesn't fit into the scheme)
*	Bugfixes part 1	orwell96	2018-06-14
| | | |	There's something wrong with the new paths, next time build a path validity checker to trace the issue
*	Occupation System, new train steps, still incomplete	orwell96	2018-06-14
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*	Adapt wagons to new path system	orwell96	2018-06-14
| | | |	Still outstanding: trains
*	Restructure path system	orwell96	2018-06-14
| | | |	The changes to the path system have not yet been integrated...
*	Add bord computer to trains	orwell96	2018-01-09
| | | | | | | |	Features: - couple/decouple trains from a driver stand - new couple lock system (owner based, overridable by 'train_remove' privilege) - all train operators can now change the inside/outside text, allows for multilines Accessible via right-click menu or by pressing Sneak+Jump keys
*	Change controls for trains (again)	orwell96	2018-01-07
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*	Decrease the amount of garbage saved in save files	orwell96	2018-01-07
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*	Remove path invalidation statement.	orwell96	2017-12-18
| | | | |	Caused problems on multiple detector rails in a row, because paths got cleared in-between a train step Also optimize some code
*	Do not spam the server chat with messages from /at_sync_ndb and trains going ↵	orwell96	2017-12-18
| | | | | |	off_track The off-track warning has moved into the info text of wagons
*	Rewrite rail connection system...	orwell96	2017-12-18
| | | | | | | | |	...to support an arbitrary number of connections for rails, which leads to these new features: - switches now get recognized by the trackworker correctly - ability to add real rail crosses During this, I also rewrote the rail registering system and the conway function (important part of path prediction) Note, developers: the track preset format changed, you might need to rewrite them according to the presets in tracks.lua if you wrote your own (possibly breaks advcarts)
*	remove superfluous parameter	orwell96	2017-11-27
| | | |	... from update_trainpart_properties call Prohibits flipping of all wagons when extent_h wasn't set
*	Add modifiable wagon extents	orwell96	2017-11-23
| | | |	This will be required for advcarts
*	Fix multiple track types not working simultaneously	orwell96	2017-11-22
| | | | | | |	Bug was caused by the drives_on table of every train and advtrains.all_tracktypes sharing the same reference, which caused advtrains.all_tracktypes to become the intersection of all train drives_on's in the world. However, this did become empty, causing nothing to work anymore.

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generated by cgit v1.2.3 (git 2.39.1) at 2025-05-30 04:47:03 +0000

/*
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 "map.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     warningstream << "Pathfinder: "
#endif

#define PATHFINDER_MAX_WAYPOINTS 700

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


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

	/** default constructor */
	PathCost() = default;

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

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

	bool valid = false;              /**< movement is possible         */
	int  value = 0;                  /**< cost of movement             */
	int  y_change = 0;               /**< change of y position of movement */
	bool updated = false;            /**< this cost has ben calculated */

};


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

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

	/** 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, const PathCost &cost);

	bool      valid = false;               /**< node is on surface                    */
	bool      target = false;              /**< node is target position               */
	bool      source = false;              /**< node is stating position              */
	int       totalcost = -1;              /**< cost to move here from starting point */
	int       estimated_cost = -1;         /**< totalcost + heuristic cost to end     */
	v3s16     sourcedir;                   /**< origin of movement for current cost   */
	v3s16     pos;                         /**< real position of node                 */
	PathCost directions[4];                /**< cost in different directions          */
	bool      is_closed = false;           /**< for A* search: if true, is in closed list */
	bool      is_open = false;             /**< for A* search: if true, is in open list */

	/* debug values */
	bool      is_element = false;          /**< node is element of path detected      */
	char      type = 'u';                  /**< Type of pathfinding node.
	                                        * u = unknown
	                                        * i = invalid
	                                        * s = surface (walkable node)
	                                        * - = non-walkable node (e.g. air) above surface
	                                        * g = other non-walkable node
                                                */
};

class Pathfinder;
class PathfinderCompareHeuristic;

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

protected:
	Pathfinder *m_pathf;

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

class ArrayGridNodeContainer : public GridNodeContainer {
public:
	virtual ~ArrayGridNodeContainer() = default;

	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() = default;

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

/** class doing pathfinding */
class Pathfinder {

public:
	Pathfinder() = delete;
	Pathfinder(Map *map, const NodeDefManager *ndef) : m_map(map), m_ndef(ndef) {}

	~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(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 (change sign of coordinates)
	 * @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);


	/* algorithm functions */

	/**
	 * calculate 2D Manhattan distance to target
	 * @param pos position to calc distance
	 * @return integer distance
	 */
	int           getXZManhattanDist(v3s16 pos);

	/**
	 * 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 current_cost, int level);

	/**
	 * try to find a path to destination using a heuristic function
	 * to estimate distance to target (A* search algorithm)
	 * @param isource start position (index pos)
	 * @param idestination end position (index pos)
	 * @return true/false path to destination has been found
	 */
	bool          updateCostHeuristic(v3s16 isource, v3s16 idestination);

	/**
	 * build a vector containing all nodes from destination to source;
	 * to be called after the node costs have been processed
	 * @param path vector to add nodes to
	 * @param ipos initial pos to check (index pos)
	 * @return true/false path has been fully built
	 */
	bool          buildPath(std::vector<v3s16> &path, v3s16 ipos);

	/**
	 * go downwards from a position until some barrier
	 * is hit.
	 * @param pos position from which to go downwards
	 * @param max_down maximum distance to go downwards
	 * @return new position after movement; if too far down,
	 * pos is returned
	 */
	v3s16         walkDownwards(v3s16 pos, unsigned int max_down);

	/* variables */
	int m_max_index_x = 0;            /**< max index of search area in x direction  */
	int m_max_index_y = 0;            /**< max index of search area in y direction  */
	int m_max_index_z = 0;            /**< max index of search area in z direction  */


	int m_searchdistance = 0;         /**< max distance to search in each direction */
	int m_maxdrop = 0;                /**< maximum number of blocks a path may drop */
	int m_maxjump = 0;                /**< maximum number of blocks a path may jump */
	int m_min_target_distance = 0;    /**< current smalest path to target           */

	bool m_prefetch = true;              /**< 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 = nullptr;

	Map *m_map = nullptr;

	const NodeDefManager *m_ndef = nullptr;

	friend class PathfinderCompareHeuristic;

#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
};

/** Helper class for the open list priority queue in the A* pathfinder
 *  to sort the pathfinder nodes by cost.
 */
class PathfinderCompareHeuristic
{
	private:
		Pathfinder *myPathfinder;
	public:
		PathfinderCompareHeuristic(Pathfinder *pf)
		{
			myPathfinder = pf;
		}
		bool operator() (v3s16 pos1, v3s16 pos2) {
			v3s16 ipos1 = myPathfinder->getIndexPos(pos1);
			v3s16 ipos2 = myPathfinder->getIndexPos(pos2);
			PathGridnode &g_pos1 = myPathfinder->getIndexElement(ipos1);
			PathGridnode &g_pos2 = myPathfinder->getIndexElement(ipos2);
			if (!g_pos1.valid)
				return false;
			if (!g_pos2.valid)
				return false;
			return g_pos1.estimated_cost > g_pos2.estimated_cost;
		}
};

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

std::vector<v3s16> get_path(Map* map, const NodeDefManager *ndef,
		v3s16 source,
		v3s16 destination,
		unsigned int searchdistance,
		unsigned int max_jump,
		unsigned int max_drop,
		PathAlgorithm algo)
{
	return Pathfinder(map, ndef).getPath(source, destination,
				searchdistance, max_jump, max_drop, algo);
}

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

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

	return *this;
}

/******************************************************************************/
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, const 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)
{
	const NodeDefManager *ndef = m_pathf->m_ndef;
	PathGridnode &elem = *p_node;

	v3s16 realpos = m_pathf->getRealPos(ipos);

	MapNode current = m_pathf->m_map->getNode(realpos);
	MapNode below   = m_pathf->m_map->getNode(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);
				initNode(ipos, &access(ipos));
			}
		}
	}
}

PathGridnode &ArrayGridNodeContainer::access(v3s16 p)
{
	return m_nodes_array[p.X * m_x_stride + p.Y * m_y_stride + p.Z];
}

MapGridNodeContainer::MapGridNodeContainer(Pathfinder *pathf)
{
	m_pathf = pathf;
}

PathGridnode &MapGridNodeContainer::access(v3s16 p)
{
	std::map<v3s16, PathGridnode>::iterator it = m_nodes.find(p);
	if (it != m_nodes.end()) {
		return it->second;
	}
	PathGridnode &n = m_nodes[p];
	initNode(p, &n);
	return n;
}



/******************************************************************************/
std::vector<v3s16> Pathfinder::getPath(v3s16 source,
							v3s16 destination,
							unsigned int searchdistance,
							unsigned int max_jump,
							unsigned int max_drop,
							PathAlgorithm algo)
{
#ifdef PATHFINDER_CALC_TIME
	timespec ts;
	clock_gettime(CLOCK_REALTIME, &ts);
#endif
	std::vector<v3s16> retval;

	//initialization
	m_searchdistance = searchdistance;
	m_maxjump = max_jump;
	m_maxdrop = max_drop;
	m_start       = source;
	m_destination = destination;
	m_min_target_distance = -1;
	m_prefetch = true;

	if (algo == PA_PLAIN_NP) {
		m_prefetch = false;
	}

	//calculate boundaries within we're allowed to search
	int min_x = MYMIN(source.X, destination.X);
	int max_x = MYMAX(source.X, destination.X);

	int min_y = MYMIN(source.Y, destination.Y);
	int max_y = MYMAX(source.Y, destination.Y);

	int min_z = MYMIN(source.Z, destination.Z);
	int max_z = MYMAX(source.Z, destination.Z);

	m_limits.MinEdge.X = min_x - searchdistance;
	m_limits.MinEdge.Y = min_y - searchdistance;
	m_limits.MinEdge.Z = min_z - searchdistance;

	m_limits.MaxEdge.X = max_x + searchdistance;
	m_limits.MaxEdge.Y = max_y + searchdistance;
	m_limits.MaxEdge.Z = max_z + searchdistance;

	v3s16 diff = m_limits.MaxEdge - m_limits.MinEdge;

	m_max_index_x = diff.X;
	m_max_index_y = diff.Y;
	m_max_index_z = diff.Z;

	delete m_nodes_container;
	if (diff.getLength() > 5) {
		m_nodes_container = new MapGridNodeContainer(this);
	} else {
		m_nodes_container = new ArrayGridNodeContainer(this, diff);
	}
#ifdef PATHFINDER_DEBUG
	printType();
	printCost();
	printYdir();
#endif

	//fail if source or destination is walkable
	MapNode node_at_pos = m_map->getNode(destination);
	if (m_ndef->get(node_at_pos).walkable) {
		VERBOSE_TARGET << "Destination is walkable. " <<
				"Pos: " << PP(destination) << std::endl;
		return retval;
	}
	node_at_pos = m_map->getNode(source);
	if (m_ndef->get(node_at_pos).walkable) {
		VERBOSE_TARGET << "Source is walkable. " <<
				"Pos: " << PP(source) << std::endl;
		return retval;
	}

	//If source pos is hovering above air, drop
	//to the first walkable node (up to m_maxdrop).
	//All algorithms expect the source pos to be *directly* above
	//a walkable node.
	v3s16 true_source = v3s16(source);
	source = walkDownwards(source, m_maxdrop);

	//If destination pos is hovering above air, go downwards
	//to the first walkable node (up to m_maxjump).
	//This means a hovering destination pos could be reached
	//by a final upwards jump.
	v3s16 true_destination = v3s16(destination);
	destination = walkDownwards(destination, m_maxjump);

	//validate and mark start and end pos

	v3s16 StartIndex  = getIndexPos(source);
	v3s16 EndIndex    = getIndexPos(destination);

	PathGridnode &startpos = getIndexElement(StartIndex);
	PathGridnode &endpos   = getIndexElement(EndIndex);

	if (!startpos.valid) {
		VERBOSE_TARGET << "Invalid startpos " <<
				"Index: " << PP(StartIndex) <<
				"Realpos: " << PP(getRealPos(StartIndex)) << std::endl;
		return retval;
	}
	if (!endpos.valid) {
		VERBOSE_TARGET << "Invalid stoppos " <<
				"Index: " << PP(EndIndex) <<
				"Realpos: " << PP(getRealPos(EndIndex)) << std::endl;
		return retval;
	}

	endpos.target      = true;
	startpos.source    = true;
	startpos.totalcost = 0;

	bool update_cost_retval = false;

	//calculate node costs
	switch (algo) {
		case PA_DIJKSTRA:
			update_cost_retval = updateAllCosts(StartIndex, v3s16(0, 0, 0), 0, 0);
			break;
		case PA_PLAIN_NP:
		case PA_PLAIN:
			update_cost_retval = updateCostHeuristic(StartIndex, EndIndex);
			break;
		default:
			ERROR_TARGET << "Missing PathAlgorithm" << std::endl;
			break;
	}

	if (update_cost_retval) {

#ifdef PATHFINDER_DEBUG
		std::cout << "Path to target found!" << std::endl;
		printPathLen();
#endif

		//find path
		std::vector<v3s16> index_path;
		buildPath(index_path, EndIndex);
		//Now we have a path of index positions,
		//and it's in reverse.
		//The "true" start or end position might be missing
		//since those have been given special treatment.

#ifdef PATHFINDER_DEBUG
		std::cout << "Index path:" << std::endl;
		printPath(index_path);
#endif
		//from here we'll make the final changes to the path
		std::vector<v3s16> full_path;

		//calculate required size
		int full_path_size = index_path.size();
		if (source != true_source) {
			full_path_size++;
		}
		if (destination != true_destination) {
			full_path_size++;
		}
		full_path.reserve(full_path_size);

		//manually add true_source to start of path, if needed
		if (source != true_source) {
			full_path.push_back(true_source);
		}
		//convert all index positions to "normal" positions and insert
		//them into full_path in reverse
		std::vector<v3s16>::reverse_iterator rit = index_path.rbegin();
		for (; rit != index_path.rend(); ++rit) {
			full_path.push_back(getIndexElement(*rit).pos);
		}
		//manually add true_destination to end of path, if needed
		if (destination != true_destination) {
			full_path.push_back(true_destination);
		}

		//Done! We now have a complete path of normal positions.


#ifdef PATHFINDER_DEBUG
		std::cout << "Full path:" << std::endl;
		printPath(full_path);
#endif
#ifdef PATHFINDER_CALC_TIME
		timespec ts2;
		clock_gettime(CLOCK_REALTIME, &ts2);

		int ms = (ts2.tv_nsec - ts.tv_nsec)/(1000*1000);
		int us = ((ts2.tv_nsec - ts.tv_nsec) - (ms*1000*1000))/1000;
		int ns = ((ts2.tv_nsec - ts.tv_nsec) - ( (ms*1000*1000) + (us*1000)));


		std::cout << "Calculating path took: " << (ts2.tv_sec - ts.tv_sec) <<
				"s " << ms << "ms " << us << "us " << ns << "ns " << std::endl;
#endif
		return full_path;
	}
	else {
#ifdef PATHFINDER_DEBUG
		printPathLen();
#endif
		INFO_TARGET << "No path found" << std::endl;
	}


	//return
	return retval;
}

Pathfinder::~Pathfinder()
{
	delete m_nodes_container;
}
/******************************************************************************/
v3s16 Pathfinder::getRealPos(v3s16 ipos)
{
	return m_limits.MinEdge + ipos;
}

/******************************************************************************/
PathCost Pathfinder::calcCost(v3s16 pos, v3s16 dir)
{
	PathCost retval;

	retval.updated = true;

	v3s16 pos2 = pos + dir;

	//check limits
	if (!m_limits.isPointInside(pos2)) {
		DEBUG_OUT("Pathfinder: " << PP(pos2) <<
				" no cost -> out of limits" << std::endl);
		return retval;
	}

	MapNode node_at_pos2 = m_map->getNode(pos2);

	//did we get information about node?
	if (node_at_pos2.param0 == CONTENT_IGNORE ) {
			VERBOSE_TARGET << "Pathfinder: (1) area at pos: "
					<< PP(pos2) << " not loaded";
			return retval;
	}

	if (!m_ndef->get(node_at_pos2).walkable) {
		MapNode node_below_pos2 =
			m_map->getNode(pos2 + v3s16(0, -1, 0));

		//did we get information about node?
		if (node_below_pos2.param0 == CONTENT_IGNORE ) {
				VERBOSE_TARGET << "Pathfinder: (2) area at pos: "
					<< PP((pos2 + v3s16(0, -1, 0))) << " not loaded";
				return retval;
		}

		//test if the same-height neighbor is suitable
		if (m_ndef->get(node_below_pos2).walkable) {
			//SUCCESS!
			retval.valid = true;
			retval.value = 1;
			retval.y_change = 0;
			DEBUG_OUT("Pathfinder: "<< PP(pos)
					<< " cost same height found" << std::endl);
		}
		else {
			//test if we can fall a couple of nodes (m_maxdrop)
			v3s16 testpos = pos2 + v3s16(0, -1, 0);
			MapNode node_at_pos = m_map->getNode(testpos);

			while ((node_at_pos.param0 != CONTENT_IGNORE) &&
					(!m_ndef->get(node_at_pos).walkable) &&
					(testpos.Y > m_limits.MinEdge.Y)) {
				testpos += v3s16(0, -1, 0);
				node_at_pos = m_map->getNode(testpos);
			}

			//did we find surface?
			if ((testpos.Y >= m_limits.MinEdge.Y) &&
					(node_at_pos.param0 != CONTENT_IGNORE) &&
					(m_ndef->get(node_at_pos).walkable)) {
				if ((pos2.Y - testpos.Y - 1) <= m_maxdrop) {
					//SUCCESS!
					retval.valid = true;
					retval.value = 2;
					//difference of y-pos +1 (target node is ABOVE solid node)
					retval.y_change = ((testpos.Y - pos2.Y) +1);
					DEBUG_OUT("Pathfinder cost below height found" << std::endl);
				}
				else {
					INFO_TARGET << "Pathfinder:"
							" distance to surface below too big: "
							<< (testpos.Y - pos2.Y) << " max: " << m_maxdrop
							<< std::endl;
				}
			}
			else {
				DEBUG_OUT("Pathfinder: no surface below found" << std::endl);
			}
		}
	}
	else {
		//test if we can jump upwards (m_maxjump)

		v3s16 targetpos = pos2; // position for jump target
		v3s16 jumppos = pos; // position for checking if jumping space is free
		MapNode node_target = m_map->getNode(targetpos);
		MapNode node_jump = m_map->getNode(jumppos);
		bool headbanger = false; // true if anything blocks jumppath

		while ((node_target.param0 != CONTENT_IGNORE) &&
				(m_ndef->get(node_target).walkable) &&
				(targetpos.Y < m_limits.MaxEdge.Y)) {
			//if the jump would hit any solid node, discard