clientobject: add null checks
[waspsaliva.git] / src / pathfinder.cpp
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1 /*
2 Minetest
3 Copyright (C) 2013 sapier, sapier at gmx dot net
4 Copyright (C) 2016 est31, <MTest31@outlook.com>
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU Lesser General Public License as published by
8 the Free Software Foundation; either version 2.1 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public License along
17 with this program; if not, write to the Free Software Foundation, Inc.,
18 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
21 /******************************************************************************/
22 /* Includes */
23 /******************************************************************************/
25 #include "pathfinder.h"
26 #include "map.h"
27 #include "nodedef.h"
29 //#define PATHFINDER_DEBUG
30 //#define PATHFINDER_CALC_TIME
32 #ifdef PATHFINDER_DEBUG
33 #include <string>
34 #endif
35 #ifdef PATHFINDER_DEBUG
36 #include <iomanip>
37 #endif
38 #ifdef PATHFINDER_CALC_TIME
39 #include <sys/time.h>
40 #endif
42 /******************************************************************************/
43 /* Typedefs and macros */
44 /******************************************************************************/
46 #define LVL "(" << level << ")" <<
48 #ifdef PATHFINDER_DEBUG
49 #define DEBUG_OUT(a) std::cout << a
50 #define INFO_TARGET std::cout
51 #define VERBOSE_TARGET std::cout
52 #define ERROR_TARGET std::cout
53 #else
54 #define DEBUG_OUT(a) while(0)
55 #define INFO_TARGET infostream << "Pathfinder: "
56 #define VERBOSE_TARGET verbosestream << "Pathfinder: "
57 #define ERROR_TARGET warningstream << "Pathfinder: "
58 #endif
60 #define PATHFINDER_MAX_WAYPOINTS 700
62 /******************************************************************************/
63 /* Class definitions */
64 /******************************************************************************/
67 /** representation of cost in specific direction */
68 class PathCost {
69 public:
71 /** default constructor */
72 PathCost() = default;
74 /** copy constructor */
75 PathCost(const PathCost &b);
77 /** assignment operator */
78 PathCost &operator= (const PathCost &b);
80 bool valid = false; /**< movement is possible */
81 int value = 0; /**< cost of movement */
82 int y_change = 0; /**< change of y position of movement */
83 bool updated = false; /**< this cost has ben calculated */
88 /** representation of a mapnode to be used for pathfinding */
89 class PathGridnode {
91 public:
92 /** default constructor */
93 PathGridnode() = default;
95 /** copy constructor */
96 PathGridnode(const PathGridnode &b);
98 /**
99 * assignment operator
100 * @param b node to copy
102 PathGridnode &operator= (const PathGridnode &b);
105 * read cost in a specific direction
106 * @param dir direction of cost to fetch
108 PathCost getCost(v3s16 dir);
111 * set cost value for movement
112 * @param dir direction to set cost for
113 * @cost cost to set
115 void setCost(v3s16 dir, const PathCost &cost);
117 bool valid = false; /**< node is on surface */
118 bool target = false; /**< node is target position */
119 bool source = false; /**< node is stating position */
120 int totalcost = -1; /**< cost to move here from starting point */
121 int estimated_cost = -1; /**< totalcost + heuristic cost to end */
122 v3s16 sourcedir; /**< origin of movement for current cost */
123 v3s16 pos; /**< real position of node */
124 PathCost directions[4]; /**< cost in different directions */
125 bool is_closed = false; /**< for A* search: if true, is in closed list */
126 bool is_open = false; /**< for A* search: if true, is in open list */
128 /* debug values */
129 bool is_element = false; /**< node is element of path detected */
130 char type = 'u'; /**< Type of pathfinding node.
131 * u = unknown
132 * i = invalid
133 * s = surface (walkable node)
134 * - = non-walkable node (e.g. air) above surface
135 * g = other non-walkable node
139 class Pathfinder;
140 class PathfinderCompareHeuristic;
142 /** Abstract class to manage the map data */
143 class GridNodeContainer {
144 public:
145 virtual PathGridnode &access(v3s16 p)=0;
146 virtual ~GridNodeContainer() = default;
148 protected:
149 Pathfinder *m_pathf;
151 void initNode(v3s16 ipos, PathGridnode *p_node);
154 class ArrayGridNodeContainer : public GridNodeContainer {
155 public:
156 virtual ~ArrayGridNodeContainer() = default;
158 ArrayGridNodeContainer(Pathfinder *pathf, v3s16 dimensions);
159 virtual PathGridnode &access(v3s16 p);
160 private:
161 v3s16 m_dimensions;
163 int m_x_stride;
164 int m_y_stride;
165 std::vector<PathGridnode> m_nodes_array;
168 class MapGridNodeContainer : public GridNodeContainer {
169 public:
170 virtual ~MapGridNodeContainer() = default;
172 MapGridNodeContainer(Pathfinder *pathf);
173 virtual PathGridnode &access(v3s16 p);
174 private:
175 std::map<v3s16, PathGridnode> m_nodes;
178 /** class doing pathfinding */
179 class Pathfinder {
181 public:
182 Pathfinder() = delete;
183 Pathfinder(Map *map, const NodeDefManager *ndef) : m_map(map), m_ndef(ndef) {}
185 ~Pathfinder();
188 * path evaluation function
189 * @param env environment to look for path
190 * @param source origin of path
191 * @param destination end position of path
192 * @param searchdistance maximum number of nodes to look in each direction
193 * @param max_jump maximum number of blocks a path may jump up
194 * @param max_drop maximum number of blocks a path may drop
195 * @param algo Algorithm to use for finding a path
197 std::vector<v3s16> getPath(v3s16 source,
198 v3s16 destination,
199 unsigned int searchdistance,
200 unsigned int max_jump,
201 unsigned int max_drop,
202 PathAlgorithm algo);
204 private:
205 /* helper functions */
208 * transform index pos to mappos
209 * @param ipos a index position
210 * @return map position
212 v3s16 getRealPos(v3s16 ipos);
215 * transform mappos to index pos
216 * @param pos a real pos
217 * @return index position
219 v3s16 getIndexPos(v3s16 pos);
222 * get gridnode at a specific index position
223 * @param ipos index position
224 * @return gridnode for index
226 PathGridnode &getIndexElement(v3s16 ipos);
229 * Get gridnode at a specific index position
230 * @return gridnode for index
232 PathGridnode &getIdxElem(s16 x, s16 y, s16 z);
235 * invert a 3D position (change sign of coordinates)
236 * @param pos 3D position
237 * @return pos *-1
239 v3s16 invert(v3s16 pos);
242 * check if a index is within current search area
243 * @param index position to validate
244 * @return true/false
246 bool isValidIndex(v3s16 index);
249 /* algorithm functions */
252 * calculate 2D Manhattan distance to target
253 * @param pos position to calc distance
254 * @return integer distance
256 int getXZManhattanDist(v3s16 pos);
259 * calculate cost of movement
260 * @param pos real world position to start movement
261 * @param dir direction to move to
262 * @return cost information
264 PathCost calcCost(v3s16 pos, v3s16 dir);
267 * recursive update whole search areas total cost information
268 * @param ipos position to check next
269 * @param srcdir positionc checked last time
270 * @param total_cost cost of moving to ipos
271 * @param level current recursion depth
272 * @return true/false path to destination has been found
274 bool updateAllCosts(v3s16 ipos, v3s16 srcdir, int current_cost, int level);
277 * try to find a path to destination using a heuristic function
278 * to estimate distance to target (A* search algorithm)
279 * @param isource start position (index pos)
280 * @param idestination end position (index pos)
281 * @return true/false path to destination has been found
283 bool updateCostHeuristic(v3s16 isource, v3s16 idestination);
286 * build a vector containing all nodes from destination to source;
287 * to be called after the node costs have been processed
288 * @param path vector to add nodes to
289 * @param ipos initial pos to check (index pos)
290 * @return true/false path has been fully built
292 bool buildPath(std::vector<v3s16> &path, v3s16 ipos);
295 * go downwards from a position until some barrier
296 * is hit.
297 * @param pos position from which to go downwards
298 * @param max_down maximum distance to go downwards
299 * @return new position after movement; if too far down,
300 * pos is returned
302 v3s16 walkDownwards(v3s16 pos, unsigned int max_down);
304 /* variables */
305 int m_max_index_x = 0; /**< max index of search area in x direction */
306 int m_max_index_y = 0; /**< max index of search area in y direction */
307 int m_max_index_z = 0; /**< max index of search area in z direction */
310 int m_searchdistance = 0; /**< max distance to search in each direction */
311 int m_maxdrop = 0; /**< maximum number of blocks a path may drop */
312 int m_maxjump = 0; /**< maximum number of blocks a path may jump */
313 int m_min_target_distance = 0; /**< current smalest path to target */
315 bool m_prefetch = true; /**< prefetch cost data */
317 v3s16 m_start; /**< source position */
318 v3s16 m_destination; /**< destination position */
320 core::aabbox3d<s16> m_limits; /**< position limits in real map coordinates */
322 /** contains all map data already collected and analyzed.
323 Access it via the getIndexElement/getIdxElem methods. */
324 friend class GridNodeContainer;
325 GridNodeContainer *m_nodes_container = nullptr;
327 Map *m_map = nullptr;
329 const NodeDefManager *m_ndef = nullptr;
331 friend class PathfinderCompareHeuristic;
333 #ifdef PATHFINDER_DEBUG
336 * print collected cost information
338 void printCost();
341 * print collected cost information in a specific direction
342 * @param dir direction to print
344 void printCost(PathDirections dir);
347 * print type of node as evaluated
349 void printType();
352 * print pathlenght for all nodes in search area
354 void printPathLen();
357 * print a path
358 * @param path path to show
360 void printPath(std::vector<v3s16> path);
363 * print y direction for all movements
365 void printYdir();
368 * print y direction for moving in a specific direction
369 * @param dir direction to show data
371 void printYdir(PathDirections dir);
374 * helper function to translate a direction to speaking text
375 * @param dir direction to translate
376 * @return textual name of direction
378 std::string dirToName(PathDirections dir);
379 #endif
382 /** Helper class for the open list priority queue in the A* pathfinder
383 * to sort the pathfinder nodes by cost.
385 class PathfinderCompareHeuristic
387 private:
388 Pathfinder *myPathfinder;
389 public:
390 PathfinderCompareHeuristic(Pathfinder *pf)
392 myPathfinder = pf;
394 bool operator() (v3s16 pos1, v3s16 pos2) {
395 v3s16 ipos1 = myPathfinder->getIndexPos(pos1);
396 v3s16 ipos2 = myPathfinder->getIndexPos(pos2);
397 PathGridnode &g_pos1 = myPathfinder->getIndexElement(ipos1);
398 PathGridnode &g_pos2 = myPathfinder->getIndexElement(ipos2);
399 if (!g_pos1.valid)
400 return false;
401 if (!g_pos2.valid)
402 return false;
403 return g_pos1.estimated_cost > g_pos2.estimated_cost;
407 /******************************************************************************/
408 /* implementation */
409 /******************************************************************************/
411 std::vector<v3s16> get_path(Map* map, const NodeDefManager *ndef,
412 v3s16 source,
413 v3s16 destination,
414 unsigned int searchdistance,
415 unsigned int max_jump,
416 unsigned int max_drop,
417 PathAlgorithm algo)
419 return Pathfinder(map, ndef).getPath(source, destination,
420 searchdistance, max_jump, max_drop, algo);
423 /******************************************************************************/
424 PathCost::PathCost(const PathCost &b)
426 valid = b.valid;
427 y_change = b.y_change;
428 value = b.value;
429 updated = b.updated;
432 /******************************************************************************/
433 PathCost &PathCost::operator= (const PathCost &b)
435 valid = b.valid;
436 y_change = b.y_change;
437 value = b.value;
438 updated = b.updated;
440 return *this;
443 /******************************************************************************/
444 PathGridnode::PathGridnode(const PathGridnode &b)
445 : valid(b.valid),
446 target(b.target),
447 source(b.source),
448 totalcost(b.totalcost),
449 sourcedir(b.sourcedir),
450 pos(b.pos),
451 is_element(b.is_element),
452 type(b.type)
455 directions[DIR_XP] = b.directions[DIR_XP];
456 directions[DIR_XM] = b.directions[DIR_XM];
457 directions[DIR_ZP] = b.directions[DIR_ZP];
458 directions[DIR_ZM] = b.directions[DIR_ZM];
461 /******************************************************************************/
462 PathGridnode &PathGridnode::operator= (const PathGridnode &b)
464 valid = b.valid;
465 target = b.target;
466 source = b.source;
467 is_element = b.is_element;
468 totalcost = b.totalcost;
469 sourcedir = b.sourcedir;
470 pos = b.pos;
471 type = b.type;
473 directions[DIR_XP] = b.directions[DIR_XP];
474 directions[DIR_XM] = b.directions[DIR_XM];
475 directions[DIR_ZP] = b.directions[DIR_ZP];
476 directions[DIR_ZM] = b.directions[DIR_ZM];
478 return *this;
481 /******************************************************************************/
482 PathCost PathGridnode::getCost(v3s16 dir)
484 if (dir.X > 0) {
485 return directions[DIR_XP];
487 if (dir.X < 0) {
488 return directions[DIR_XM];
490 if (dir.Z > 0) {
491 return directions[DIR_ZP];
493 if (dir.Z < 0) {
494 return directions[DIR_ZM];
496 PathCost retval;
497 return retval;
500 /******************************************************************************/
501 void PathGridnode::setCost(v3s16 dir, const PathCost &cost)
503 if (dir.X > 0) {
504 directions[DIR_XP] = cost;
506 if (dir.X < 0) {
507 directions[DIR_XM] = cost;
509 if (dir.Z > 0) {
510 directions[DIR_ZP] = cost;
512 if (dir.Z < 0) {
513 directions[DIR_ZM] = cost;
517 void GridNodeContainer::initNode(v3s16 ipos, PathGridnode *p_node)
519 const NodeDefManager *ndef = m_pathf->m_ndef;
520 PathGridnode &elem = *p_node;
522 v3s16 realpos = m_pathf->getRealPos(ipos);
524 MapNode current = m_pathf->m_map->getNode(realpos);
525 MapNode below = m_pathf->m_map->getNode(realpos + v3s16(0, -1, 0));
528 if ((current.param0 == CONTENT_IGNORE) ||
529 (below.param0 == CONTENT_IGNORE)) {
530 DEBUG_OUT("Pathfinder: " << PP(realpos) <<
531 " current or below is invalid element" << std::endl);
532 if (current.param0 == CONTENT_IGNORE) {
533 elem.type = 'i';
534 DEBUG_OUT(PP(ipos) << ": " << 'i' << std::endl);
536 return;
539 //don't add anything if it isn't an air node
540 if (ndef->get(current).walkable || !ndef->get(below).walkable) {
541 DEBUG_OUT("Pathfinder: " << PP(realpos)
542 << " not on surface" << std::endl);
543 if (ndef->get(current).walkable) {
544 elem.type = 's';
545 DEBUG_OUT(PP(ipos) << ": " << 's' << std::endl);
546 } else {
547 elem.type = '-';
548 DEBUG_OUT(PP(ipos) << ": " << '-' << std::endl);
550 return;
553 elem.valid = true;
554 elem.pos = realpos;
555 elem.type = 'g';
556 DEBUG_OUT(PP(ipos) << ": " << 'a' << std::endl);
558 if (m_pathf->m_prefetch) {
559 elem.directions[DIR_XP] = m_pathf->calcCost(realpos, v3s16( 1, 0, 0));
560 elem.directions[DIR_XM] = m_pathf->calcCost(realpos, v3s16(-1, 0, 0));
561 elem.directions[DIR_ZP] = m_pathf->calcCost(realpos, v3s16( 0, 0, 1));
562 elem.directions[DIR_ZM] = m_pathf->calcCost(realpos, v3s16( 0, 0,-1));
566 ArrayGridNodeContainer::ArrayGridNodeContainer(Pathfinder *pathf, v3s16 dimensions) :
567 m_x_stride(dimensions.Y * dimensions.Z),
568 m_y_stride(dimensions.Z)
570 m_pathf = pathf;
572 m_nodes_array.resize(dimensions.X * dimensions.Y * dimensions.Z);
573 INFO_TARGET << "Pathfinder ArrayGridNodeContainer constructor." << std::endl;
574 for (int x = 0; x < dimensions.X; x++) {
575 for (int y = 0; y < dimensions.Y; y++) {
576 for (int z= 0; z < dimensions.Z; z++) {
577 v3s16 ipos(x, y, z);
578 initNode(ipos, &access(ipos));
584 PathGridnode &ArrayGridNodeContainer::access(v3s16 p)
586 return m_nodes_array[p.X * m_x_stride + p.Y * m_y_stride + p.Z];
589 MapGridNodeContainer::MapGridNodeContainer(Pathfinder *pathf)
591 m_pathf = pathf;
594 PathGridnode &MapGridNodeContainer::access(v3s16 p)
596 std::map<v3s16, PathGridnode>::iterator it = m_nodes.find(p);
597 if (it != m_nodes.end()) {
598 return it->second;
600 PathGridnode &n = m_nodes[p];
601 initNode(p, &n);
602 return n;
607 /******************************************************************************/
608 std::vector<v3s16> Pathfinder::getPath(v3s16 source,
609 v3s16 destination,
610 unsigned int searchdistance,
611 unsigned int max_jump,
612 unsigned int max_drop,
613 PathAlgorithm algo)
615 #ifdef PATHFINDER_CALC_TIME
616 timespec ts;
617 clock_gettime(CLOCK_REALTIME, &ts);
618 #endif
619 std::vector<v3s16> retval;
621 //initialization
622 m_searchdistance = searchdistance;
623 m_maxjump = max_jump;
624 m_maxdrop = max_drop;
625 m_start = source;
626 m_destination = destination;
627 m_min_target_distance = -1;
628 m_prefetch = true;
630 if (algo == PA_PLAIN_NP) {
631 m_prefetch = false;
634 //calculate boundaries within we're allowed to search
635 int min_x = MYMIN(source.X, destination.X);
636 int max_x = MYMAX(source.X, destination.X);
638 int min_y = MYMIN(source.Y, destination.Y);
639 int max_y = MYMAX(source.Y, destination.Y);
641 int min_z = MYMIN(source.Z, destination.Z);
642 int max_z = MYMAX(source.Z, destination.Z);
644 m_limits.MinEdge.X = min_x - searchdistance;
645 m_limits.MinEdge.Y = min_y - searchdistance;
646 m_limits.MinEdge.Z = min_z - searchdistance;
648 m_limits.MaxEdge.X = max_x + searchdistance;
649 m_limits.MaxEdge.Y = max_y + searchdistance;
650 m_limits.MaxEdge.Z = max_z + searchdistance;
652 v3s16 diff = m_limits.MaxEdge - m_limits.MinEdge;
654 m_max_index_x = diff.X;
655 m_max_index_y = diff.Y;
656 m_max_index_z = diff.Z;
658 delete m_nodes_container;
659 if (diff.getLength() > 5) {
660 m_nodes_container = new MapGridNodeContainer(this);
661 } else {
662 m_nodes_container = new ArrayGridNodeContainer(this, diff);
664 #ifdef PATHFINDER_DEBUG
665 printType();
666 printCost();
667 printYdir();
668 #endif
670 //fail if source or destination is walkable
671 MapNode node_at_pos = m_map->getNode(destination);
672 if (m_ndef->get(node_at_pos).walkable) {
673 VERBOSE_TARGET << "Destination is walkable. " <<
674 "Pos: " << PP(destination) << std::endl;
675 return retval;
677 node_at_pos = m_map->getNode(source);
678 if (m_ndef->get(node_at_pos).walkable) {
679 VERBOSE_TARGET << "Source is walkable. " <<
680 "Pos: " << PP(source) << std::endl;
681 return retval;
684 //If source pos is hovering above air, drop
685 //to the first walkable node (up to m_maxdrop).
686 //All algorithms expect the source pos to be *directly* above
687 //a walkable node.
688 v3s16 true_source = v3s16(source);
689 source = walkDownwards(source, m_maxdrop);
691 //If destination pos is hovering above air, go downwards
692 //to the first walkable node (up to m_maxjump).
693 //This means a hovering destination pos could be reached
694 //by a final upwards jump.
695 v3s16 true_destination = v3s16(destination);
696 destination = walkDownwards(destination, m_maxjump);
698 //validate and mark start and end pos
700 v3s16 StartIndex = getIndexPos(source);
701 v3s16 EndIndex = getIndexPos(destination);
703 PathGridnode &startpos = getIndexElement(StartIndex);
704 PathGridnode &endpos = getIndexElement(EndIndex);
706 if (!startpos.valid) {
707 VERBOSE_TARGET << "Invalid startpos " <<
708 "Index: " << PP(StartIndex) <<
709 "Realpos: " << PP(getRealPos(StartIndex)) << std::endl;
710 return retval;
712 if (!endpos.valid) {
713 VERBOSE_TARGET << "Invalid stoppos " <<
714 "Index: " << PP(EndIndex) <<
715 "Realpos: " << PP(getRealPos(EndIndex)) << std::endl;
716 return retval;
719 endpos.target = true;
720 startpos.source = true;
721 startpos.totalcost = 0;
723 bool update_cost_retval = false;
725 //calculate node costs
726 switch (algo) {
727 case PA_DIJKSTRA:
728 update_cost_retval = updateAllCosts(StartIndex, v3s16(0, 0, 0), 0, 0);
729 break;
730 case PA_PLAIN_NP:
731 case PA_PLAIN:
732 update_cost_retval = updateCostHeuristic(StartIndex, EndIndex);
733 break;
734 default:
735 ERROR_TARGET << "Missing PathAlgorithm" << std::endl;
736 break;
739 if (update_cost_retval) {
741 #ifdef PATHFINDER_DEBUG
742 std::cout << "Path to target found!" << std::endl;
743 printPathLen();
744 #endif
746 //find path
747 std::vector<v3s16> index_path;
748 buildPath(index_path, EndIndex);
749 //Now we have a path of index positions,
750 //and it's in reverse.
751 //The "true" start or end position might be missing
752 //since those have been given special treatment.
754 #ifdef PATHFINDER_DEBUG
755 std::cout << "Index path:" << std::endl;
756 printPath(index_path);
757 #endif
758 //from here we'll make the final changes to the path
759 std::vector<v3s16> full_path;
761 //calculate required size
762 int full_path_size = index_path.size();
763 if (source != true_source) {
764 full_path_size++;
766 if (destination != true_destination) {
767 full_path_size++;
769 full_path.reserve(full_path_size);
771 //manually add true_source to start of path, if needed
772 if (source != true_source) {
773 full_path.push_back(true_source);
775 //convert all index positions to "normal" positions and insert
776 //them into full_path in reverse
777 std::vector<v3s16>::reverse_iterator rit = index_path.rbegin();
778 for (; rit != index_path.rend(); ++rit) {
779 full_path.push_back(getIndexElement(*rit).pos);
781 //manually add true_destination to end of path, if needed
782 if (destination != true_destination) {
783 full_path.push_back(true_destination);
786 //Done! We now have a complete path of normal positions.
789 #ifdef PATHFINDER_DEBUG
790 std::cout << "Full path:" << std::endl;
791 printPath(full_path);
792 #endif
793 #ifdef PATHFINDER_CALC_TIME
794 timespec ts2;
795 clock_gettime(CLOCK_REALTIME, &ts2);
797 int ms = (ts2.tv_nsec - ts.tv_nsec)/(1000*1000);
798 int us = ((ts2.tv_nsec - ts.tv_nsec) - (ms*1000*1000))/1000;
799 int ns = ((ts2.tv_nsec - ts.tv_nsec) - ( (ms*1000*1000) + (us*1000)));
802 std::cout << "Calculating path took: " << (ts2.tv_sec - ts.tv_sec) <<
803 "s " << ms << "ms " << us << "us " << ns << "ns " << std::endl;
804 #endif
805 return full_path;
807 else {
808 #ifdef PATHFINDER_DEBUG
809 printPathLen();
810 #endif
811 INFO_TARGET << "No path found" << std::endl;
815 //return
816 return retval;
819 Pathfinder::~Pathfinder()
821 delete m_nodes_container;
823 /******************************************************************************/
824 v3s16 Pathfinder::getRealPos(v3s16 ipos)
826 return m_limits.MinEdge + ipos;
829 /******************************************************************************/
830 PathCost Pathfinder::calcCost(v3s16 pos, v3s16 dir)
832 PathCost retval;
834 retval.updated = true;
836 v3s16 pos2 = pos + dir;
838 //check limits
839 if (!m_limits.isPointInside(pos2)) {
840 DEBUG_OUT("Pathfinder: " << PP(pos2) <<
841 " no cost -> out of limits" << std::endl);
842 return retval;
845 MapNode node_at_pos2 = m_map->getNode(pos2);
847 //did we get information about node?
848 if (node_at_pos2.param0 == CONTENT_IGNORE ) {
849 VERBOSE_TARGET << "Pathfinder: (1) area at pos: "
850 << PP(pos2) << " not loaded";
851 return retval;
854 if (!m_ndef->get(node_at_pos2).walkable) {
855 MapNode node_below_pos2 =
856 m_map->getNode(pos2 + v3s16(0, -1, 0));
858 //did we get information about node?
859 if (node_below_pos2.param0 == CONTENT_IGNORE ) {
860 VERBOSE_TARGET << "Pathfinder: (2) area at pos: "
861 << PP((pos2 + v3s16(0, -1, 0))) << " not loaded";
862 return retval;
865 //test if the same-height neighbor is suitable
866 if (m_ndef->get(node_below_pos2).walkable) {
867 //SUCCESS!
868 retval.valid = true;
869 retval.value = 1;
870 retval.y_change = 0;
871 DEBUG_OUT("Pathfinder: "<< PP(pos)
872 << " cost same height found" << std::endl);
874 else {
875 //test if we can fall a couple of nodes (m_maxdrop)
876 v3s16 testpos = pos2 + v3s16(0, -1, 0);
877 MapNode node_at_pos = m_map->getNode(testpos);
879 while ((node_at_pos.param0 != CONTENT_IGNORE) &&
880 (!m_ndef->get(node_at_pos).walkable) &&
881 (testpos.Y > m_limits.MinEdge.Y)) {
882 testpos += v3s16(0, -1, 0);
883 node_at_pos = m_map->getNode(testpos);
886 //did we find surface?
887 if ((testpos.Y >= m_limits.MinEdge.Y) &&
888 (node_at_pos.param0 != CONTENT_IGNORE) &&
889 (m_ndef->get(node_at_pos).walkable)) {
890 if ((pos2.Y - testpos.Y - 1) <= m_maxdrop) {
891 //SUCCESS!
892 retval.valid = true;
893 retval.value = 2;
894 //difference of y-pos +1 (target node is ABOVE solid node)
895 retval.y_change = ((testpos.Y - pos2.Y) +1);
896 DEBUG_OUT("Pathfinder cost below height found" << std::endl);
898 else {
899 INFO_TARGET << "Pathfinder:"
900 " distance to surface below too big: "
901 << (testpos.Y - pos2.Y) << " max: " << m_maxdrop
902 << std::endl;
905 else {
906 DEBUG_OUT("Pathfinder: no surface below found" << std::endl);
910 else {
911 //test if we can jump upwards (m_maxjump)
913 v3s16 targetpos = pos2; // position for jump target
914 v3s16 jumppos = pos; // position for checking if jumping space is free
915 MapNode node_target = m_map->getNode(targetpos);
916 MapNode node_jump = m_map->getNode(jumppos);
917 bool headbanger = false; // true if anything blocks jumppath
919 while ((node_target.param0 != CONTENT_IGNORE) &&
920 (m_ndef->get(node_target).walkable) &&
921 (targetpos.Y < m_limits.MaxEdge.Y)) {
922 //if the jump would hit any solid node, discard
923 if ((node_jump.param0 == CONTENT_IGNORE) ||
924 (m_ndef->get(node_jump).walkable)) {
925 headbanger = true;
926 break;
928 targetpos += v3s16(0, 1, 0);
929 jumppos += v3s16(0, 1, 0);
930 node_target = m_map->getNode(targetpos);
931 node_jump = m_map->getNode(jumppos);
934 //check headbanger one last time
935 if ((node_jump.param0 == CONTENT_IGNORE) ||
936 (m_ndef->get(node_jump).walkable)) {
937 headbanger = true;
940 //did we find surface without banging our head?
941 if ((!headbanger) && (targetpos.Y <= m_limits.MaxEdge.Y) &&
942 (!m_ndef->get(node_target).walkable)) {
944 if (targetpos.Y - pos2.Y <= m_maxjump) {
945 //SUCCESS!
946 retval.valid = true;
947 retval.value = 2;
948 retval.y_change = (targetpos.Y - pos2.Y);
949 DEBUG_OUT("Pathfinder cost above found" << std::endl);
951 else {
952 DEBUG_OUT("Pathfinder: distance to surface above too big: "
953 << (targetpos.Y - pos2.Y) << " max: " << m_maxjump
954 << std::endl);
957 else {
958 DEBUG_OUT("Pathfinder: no surface above found" << std::endl);
961 return retval;
964 /******************************************************************************/
965 v3s16 Pathfinder::getIndexPos(v3s16 pos)
967 return pos - m_limits.MinEdge;
970 /******************************************************************************/
971 PathGridnode &Pathfinder::getIndexElement(v3s16 ipos)
973 return m_nodes_container->access(ipos);
976 /******************************************************************************/
977 inline PathGridnode &Pathfinder::getIdxElem(s16 x, s16 y, s16 z)
979 return m_nodes_container->access(v3s16(x,y,z));
982 /******************************************************************************/
983 bool Pathfinder::isValidIndex(v3s16 index)
985 if ( (index.X < m_max_index_x) &&
986 (index.Y < m_max_index_y) &&
987 (index.Z < m_max_index_z) &&
988 (index.X >= 0) &&
989 (index.Y >= 0) &&
990 (index.Z >= 0))
991 return true;
993 return false;
996 /******************************************************************************/
997 v3s16 Pathfinder::invert(v3s16 pos)
999 v3s16 retval = pos;
1001 retval.X *=-1;
1002 retval.Y *=-1;
1003 retval.Z *=-1;
1005 return retval;
1008 /******************************************************************************/
1009 bool Pathfinder::updateAllCosts(v3s16 ipos,
1010 v3s16 srcdir,
1011 int current_cost,
1012 int level)
1014 PathGridnode &g_pos = getIndexElement(ipos);
1015 g_pos.totalcost = current_cost;
1016 g_pos.sourcedir = srcdir;
1018 level ++;
1020 //check if target has been found
1021 if (g_pos.target) {
1022 m_min_target_distance = current_cost;
1023 DEBUG_OUT(LVL " Pathfinder: target found!" << std::endl);
1024 return true;
1027 bool retval = false;
1029 // the 4 cardinal directions
1030 const static v3s16 directions[4] = {
1031 v3s16(1,0, 0),
1032 v3s16(-1,0, 0),
1033 v3s16(0,0, 1),
1034 v3s16(0,0,-1)
1037 for (v3s16 direction : directions) {
1038 if (direction != srcdir) {
1039 PathCost cost = g_pos.getCost(direction);
1041 if (cost.valid) {
1042 direction.Y = cost.y_change;
1044 v3s16 ipos2 = ipos + direction;
1046 if (!isValidIndex(ipos2)) {
1047 DEBUG_OUT(LVL " Pathfinder: " << PP(ipos2) <<
1048 " out of range, max=" << PP(m_limits.MaxEdge) << std::endl);
1049 continue;
1052 PathGridnode &g_pos2 = getIndexElement(ipos2);
1054 if (!g_pos2.valid) {
1055 VERBOSE_TARGET << LVL "Pathfinder: no data for new position: "
1056 << PP(ipos2) << std::endl;
1057 continue;
1060 assert(cost.value > 0);
1062 int new_cost = current_cost + cost.value;
1064 // check if there already is a smaller path
1065 if ((m_min_target_distance > 0) &&
1066 (m_min_target_distance < new_cost)) {
1067 return false;
1070 if ((g_pos2.totalcost < 0) ||
1071 (g_pos2.totalcost > new_cost)) {
1072 DEBUG_OUT(LVL "Pathfinder: updating path at: "<<
1073 PP(ipos2) << " from: " << g_pos2.totalcost << " to "<<
1074 new_cost << std::endl);
1075 if (updateAllCosts(ipos2, invert(direction),
1076 new_cost, level)) {
1077 retval = true;
1080 else {
1081 DEBUG_OUT(LVL "Pathfinder:"
1082 " already found shorter path to: "
1083 << PP(ipos2) << std::endl);
1086 else {
1087 DEBUG_OUT(LVL "Pathfinder:"
1088 " not moving to invalid direction: "
1089 << PP(directions[i]) << std::endl);
1093 return retval;
1096 /******************************************************************************/
1097 int Pathfinder::getXZManhattanDist(v3s16 pos)
1099 int min_x = MYMIN(pos.X, m_destination.X);
1100 int max_x = MYMAX(pos.X, m_destination.X);
1101 int min_z = MYMIN(pos.Z, m_destination.Z);
1102 int max_z = MYMAX(pos.Z, m_destination.Z);
1104 return (max_x - min_x) + (max_z - min_z);
1109 /******************************************************************************/
1110 bool Pathfinder::updateCostHeuristic(v3s16 isource, v3s16 idestination)
1112 // A* search algorithm.
1114 // The open list contains the pathfinder nodes that still need to be
1115 // checked. The priority queue sorts the pathfinder nodes by
1116 // estimated cost, with lowest cost on the top.
1117 std::priority_queue<v3s16, std::vector<v3s16>, PathfinderCompareHeuristic>
1118 openList(PathfinderCompareHeuristic(this));
1120 v3s16 source = getRealPos(isource);
1121 v3s16 destination = getRealPos(idestination);
1123 // initial position
1124 openList.push(source);
1126 // the 4 cardinal directions
1127 const static v3s16 directions[4] = {
1128 v3s16(1,0, 0),
1129 v3s16(-1,0, 0),
1130 v3s16(0,0, 1),
1131 v3s16(0,0,-1)
1134 v3s16 current_pos;
1135 PathGridnode& s_pos = getIndexElement(isource);
1136 s_pos.source = true;
1137 s_pos.totalcost = 0;
1139 // estimated cost from start to finish
1140 int cur_manhattan = getXZManhattanDist(destination);
1141 s_pos.estimated_cost = cur_manhattan;
1143 while (!openList.empty()) {
1144 // Pick node with lowest total cost estimate.
1145 // The "cheapest" node is always on top.
1146 current_pos = openList.top();
1147 openList.pop();
1148 v3s16 ipos = getIndexPos(current_pos);
1150 // check if node is inside searchdistance and valid
1151 if (!isValidIndex(ipos)) {
1152 DEBUG_OUT(LVL " Pathfinder: " << PP(current_pos) <<
1153 " out of search distance, max=" << PP(m_limits.MaxEdge) << std::endl);
1154 continue;
1157 PathGridnode& g_pos = getIndexElement(ipos);
1158 g_pos.is_closed = true;
1159 g_pos.is_open = false;
1160 if (!g_pos.valid) {
1161 continue;
1164 if (current_pos == destination) {
1165 // destination found, terminate
1166 g_pos.target = true;
1167 return true;
1170 // for this node, check the 4 cardinal directions
1171 for (v3s16 direction_flat : directions) {
1172 int current_totalcost = g_pos.totalcost;
1174 // get cost from current node to currently checked direction
1175 PathCost cost = g_pos.getCost(direction_flat);
1176 if (!cost.updated) {
1177 cost = calcCost(current_pos, direction_flat);
1178 g_pos.setCost(direction_flat, cost);
1180 // update Y component of direction if neighbor requires jump or fall
1181 v3s16 direction_3d = v3s16(direction_flat);
1182 direction_3d.Y = cost.y_change;
1184 // get position of true neighbor
1185 v3s16 neighbor = current_pos + direction_3d;
1186 v3s16 ineighbor = getIndexPos(neighbor);
1187 PathGridnode &n_pos = getIndexElement(ineighbor);
1189 if (cost.valid && !n_pos.is_closed && !n_pos.is_open) {
1190 // heuristic function; estimate cost from neighbor to destination
1191 cur_manhattan = getXZManhattanDist(neighbor);
1193 // add neighbor to open list
1194 n_pos.sourcedir = invert(direction_3d);
1195 n_pos.totalcost = current_totalcost + cost.value;
1196 n_pos.estimated_cost = current_totalcost + cost.value + cur_manhattan;
1197 n_pos.is_open = true;
1198 openList.push(neighbor);
1202 // no path found; all possible nodes within searchdistance have been exhausted
1203 return false;
1206 /******************************************************************************/
1207 bool Pathfinder::buildPath(std::vector<v3s16> &path, v3s16 ipos)
1209 // The cost calculation should have set a source direction for all relevant nodes.
1210 // To build the path, we go backwards from the destination until we reach the start.
1211 for(u32 waypoints = 1; waypoints++; ) {
1212 if (waypoints > PATHFINDER_MAX_WAYPOINTS) {
1213 ERROR_TARGET << "Pathfinder: buildPath: path is too long (too many waypoints), aborting" << std::endl;
1214 return false;
1216 // Insert node into path
1217 PathGridnode &g_pos = getIndexElement(ipos);
1218 if (!g_pos.valid) {
1219 ERROR_TARGET << "Pathfinder: buildPath: invalid next pos detected, aborting" << std::endl;
1220 return false;
1223 g_pos.is_element = true;
1224 path.push_back(ipos);
1225 if (g_pos.source)
1226 // start node found, terminate
1227 return true;
1229 // go to the node from which the pathfinder came
1230 ipos += g_pos.sourcedir;
1233 ERROR_TARGET << "Pathfinder: buildPath: no source node found" << std::endl;
1234 return false;
1237 /******************************************************************************/
1238 v3s16 Pathfinder::walkDownwards(v3s16 pos, unsigned int max_down) {
1239 if (max_down == 0)
1240 return pos;
1241 v3s16 testpos = v3s16(pos);
1242 MapNode node_at_pos = m_map->getNode(testpos);
1243 unsigned int down = 0;
1244 while ((node_at_pos.param0 != CONTENT_IGNORE) &&
1245 (!m_ndef->get(node_at_pos).walkable) &&
1246 (testpos.Y > m_limits.MinEdge.Y) &&
1247 (down <= max_down)) {
1248 testpos += v3s16(0, -1, 0);
1249 down++;
1250 node_at_pos = m_map->getNode(testpos);
1252 //did we find surface?
1253 if ((testpos.Y >= m_limits.MinEdge.Y) &&
1254 (node_at_pos.param0 != CONTENT_IGNORE) &&
1255 (m_ndef->get(node_at_pos).walkable)) {
1256 if (down == 0) {
1257 pos = testpos;
1258 } else if ((down - 1) <= max_down) {
1259 //difference of y-pos +1 (target node is ABOVE solid node)
1260 testpos += v3s16(0, 1, 0);
1261 pos = testpos;
1263 else {
1264 VERBOSE_TARGET << "Pos too far above ground: " <<
1265 "Index: " << PP(getIndexPos(pos)) <<
1266 "Realpos: " << PP(getRealPos(getIndexPos(pos))) << std::endl;
1268 } else {
1269 DEBUG_OUT("Pathfinder: no surface found below pos" << std::endl);
1271 return pos;
1274 #ifdef PATHFINDER_DEBUG
1276 /******************************************************************************/
1277 void Pathfinder::printCost()
1279 printCost(DIR_XP);
1280 printCost(DIR_XM);
1281 printCost(DIR_ZP);
1282 printCost(DIR_ZM);
1285 /******************************************************************************/
1286 void Pathfinder::printYdir()
1288 printYdir(DIR_XP);
1289 printYdir(DIR_XM);
1290 printYdir(DIR_ZP);
1291 printYdir(DIR_ZM);
1294 /******************************************************************************/
1295 void Pathfinder::printCost(PathDirections dir)
1297 std::cout << "Cost in direction: " << dirToName(dir) << std::endl;
1298 std::cout << std::setfill('-') << std::setw(80) << "-" << std::endl;
1299 std::cout << std::setfill(' ');
1300 for (int y = 0; y < m_max_index_y; y++) {
1302 std::cout << "Level: " << y << std::endl;
1304 std::cout << std::setw(4) << " " << " ";
1305 for (int x = 0; x < m_max_index_x; x++) {
1306 std::cout << std::setw(4) << x;
1308 std::cout << std::endl;
1310 for (int z = 0; z < m_max_index_z; z++) {
1311 std::cout << std::setw(4) << z <<": ";
1312 for (int x = 0; x < m_max_index_x; x++) {
1313 if (getIdxElem(x, y, z).directions[dir].valid)
1314 std::cout << std::setw(4)
1315 << getIdxElem(x, y, z).directions[dir].value;
1316 else
1317 std::cout << std::setw(4) << "-";
1319 std::cout << std::endl;
1321 std::cout << std::endl;
1325 /******************************************************************************/
1326 void Pathfinder::printYdir(PathDirections dir)
1328 std::cout << "Height difference in direction: " << dirToName(dir) << std::endl;
1329 std::cout << std::setfill('-') << std::setw(80) << "-" << std::endl;
1330 std::cout << std::setfill(' ');
1331 for (int y = 0; y < m_max_index_y; y++) {
1333 std::cout << "Level: " << y << std::endl;
1335 std::cout << std::setw(4) << " " << " ";
1336 for (int x = 0; x < m_max_index_x; x++) {
1337 std::cout << std::setw(4) << x;
1339 std::cout << std::endl;
1341 for (int z = 0; z < m_max_index_z; z++) {
1342 std::cout << std::setw(4) << z <<": ";
1343 for (int x = 0; x < m_max_index_x; x++) {
1344 if (getIdxElem(x, y, z).directions[dir].valid)
1345 std::cout << std::setw(4)
1346 << getIdxElem(x, y, z).directions[dir].y_change;
1347 else
1348 std::cout << std::setw(4) << "-";
1350 std::cout << std::endl;
1352 std::cout << std::endl;
1356 /******************************************************************************/
1357 void Pathfinder::printType()
1359 std::cout << "Type of node:" << std::endl;
1360 std::cout << std::setfill('-') << std::setw(80) << "-" << std::endl;
1361 std::cout << std::setfill(' ');
1362 for (int y = 0; y < m_max_index_y; y++) {
1364 std::cout << "Level: " << y << std::endl;
1366 std::cout << std::setw(3) << " " << " ";
1367 for (int x = 0; x < m_max_index_x; x++) {
1368 std::cout << std::setw(3) << x;
1370 std::cout << std::endl;
1372 for (int z = 0; z < m_max_index_z; z++) {
1373 std::cout << std::setw(3) << z <<": ";
1374 for (int x = 0; x < m_max_index_x; x++) {
1375 char toshow = getIdxElem(x, y, z).type;
1376 std::cout << std::setw(3) << toshow;
1378 std::cout << std::endl;
1380 std::cout << std::endl;
1382 std::cout << std::endl;
1385 /******************************************************************************/
1386 void Pathfinder::printPathLen()
1388 std::cout << "Pathlen:" << std::endl;
1389 std::cout << std::setfill('-') << std::setw(80) << "-" << std::endl;
1390 std::cout << std::setfill(' ');
1391 for (int y = 0; y < m_max_index_y; y++) {
1393 std::cout << "Level: " << y << std::endl;
1395 std::cout << std::setw(3) << " " << " ";
1396 for (int x = 0; x < m_max_index_x; x++) {
1397 std::cout << std::setw(3) << x;
1399 std::cout << std::endl;
1401 for (int z = 0; z < m_max_index_z; z++) {
1402 std::cout << std::setw(3) << z <<": ";
1403 for (int x = 0; x < m_max_index_x; x++) {
1404 std::cout << std::setw(3) << getIdxElem(x, y, z).totalcost;
1406 std::cout << std::endl;
1408 std::cout << std::endl;
1410 std::cout << std::endl;
1413 /******************************************************************************/
1414 std::string Pathfinder::dirToName(PathDirections dir)
1416 switch (dir) {
1417 case DIR_XP:
1418 return "XP";
1419 break;
1420 case DIR_XM:
1421 return "XM";
1422 break;
1423 case DIR_ZP:
1424 return "ZP";
1425 break;
1426 case DIR_ZM:
1427 return "ZM";
1428 break;
1429 default:
1430 return "UKN";
1434 /******************************************************************************/
1435 void Pathfinder::printPath(std::vector<v3s16> path)
1437 unsigned int current = 0;
1438 for (std::vector<v3s16>::iterator i = path.begin();
1439 i != path.end(); ++i) {
1440 std::cout << std::setw(3) << current << ":" << PP((*i)) << std::endl;
1441 current++;
1445 #endif