-
-
Notifications
You must be signed in to change notification settings - Fork 1k
/
pathfind.cpp
1008 lines (886 loc) · 34.6 KB
/
pathfind.cpp
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
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
/*
Copyright (C) 2005 - 2024
by Guillaume Melquiond <guillaume.melquiond@gmail.com>
Copyright (C) 2003 by David White <dave@whitevine.net>
Part of the Battle for Wesnoth Project https://www.wesnoth.org/
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 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.
See the COPYING file for more details.
*/
/**
* @file
* Various pathfinding functions and utilities.
*/
#include "pathfind/pathfind.hpp"
#include "pathfind/teleport.hpp"
#include "display.hpp"
#include "game_board.hpp"
#include "gettext.hpp"
#include "log.hpp"
#include "map/map.hpp"
#include "resources.hpp"
#include "team.hpp"
#include "units/unit.hpp"
#include "units/map.hpp"
#include "wml_exception.hpp"
#include <vector>
#include <algorithm>
static lg::log_domain log_engine("engine");
#define ERR_PF LOG_STREAM(err, log_engine)
namespace pathfind {
/**
* Function that will find a location on the board that is as near
* to @a loc as possible, but which is unoccupied by any units.
* If no valid location can be found, it will return a null location.
* If @a pass_check is provided, the found location must have a terrain
* that this unit can enter.
* If @a shroud_check is provided, only locations not covered by this
* team's shroud will be considered.
*/
map_location find_vacant_tile(const map_location& loc, VACANT_TILE_TYPE vacancy,
const unit* pass_check, const team* shroud_check, const game_board* board)
{
if (!board) {
board = resources::gameboard;
assert(board);
}
const gamemap & map = board->map();
const unit_map & units = board->units();
if (!map.on_board(loc)) return map_location();
const bool do_shroud = shroud_check && shroud_check->uses_shroud();
std::set<map_location> pending_tiles_to_check, tiles_checked;
pending_tiles_to_check.insert(loc);
// Iterate out 50 hexes from loc
for (int distance = 0; distance < 50; ++distance) {
if (pending_tiles_to_check.empty())
return map_location();
//Copy over the hexes to check and clear the old set
std::set<map_location> tiles_checking;
tiles_checking.swap(pending_tiles_to_check);
//Iterate over all the hexes we need to check
for (const map_location &l : tiles_checking)
{
// Skip shrouded locations.
if ( do_shroud && shroud_check->shrouded(l) )
continue;
//If this area is not a castle but should, skip it.
if ( vacancy == VACANT_CASTLE && !map.is_castle(l) ) continue;
const bool pass_check_and_unreachable = pass_check
&& pass_check->movement_cost(map[l]) == movetype::UNREACHABLE;
//If the unit can't reach the tile and we have searched
//an area of at least radius 10 (arbitrary), skip the tile.
//Necessary for cases such as an unreachable
//starting hex surrounded by 6 other unreachable hexes, in which case
//the algorithm would not even search distance==1
//even if there's a reachable hex for distance==2.
if (pass_check_and_unreachable && distance > 10) continue;
//If the hex is empty and we do either no pass check or the hex is reachable, return it.
if (units.find(l) == units.end() && !pass_check_and_unreachable) return l;
for(const map_location& l2 : get_adjacent_tiles(l)) {
if (!map.on_board(l2)) continue;
// Add the tile to be checked if it hasn't already been and
// isn't being checked.
if (tiles_checked.find(l2) == tiles_checked.end() &&
tiles_checking.find(l2) == tiles_checking.end())
{
pending_tiles_to_check.insert(l2);
}
}
}
tiles_checked.swap(tiles_checking);
}
return map_location();
}
/**
* Wrapper for find_vacant_tile() when looking for a vacant castle tile
* near a leader.
* If no valid location can be found, it will return a null location.
*/
map_location find_vacant_castle(const unit & leader)
{
return find_vacant_tile(leader.get_location(), VACANT_CASTLE,
nullptr, &resources::gameboard->get_team(leader.side()));
}
/**
* Determines if a given location is in an enemy zone of control.
*
* @param current_team The moving team (only ZoC of enemies of this team are considered).
* @param loc The location to check.
* @param viewing_team Only units visible to this team are considered.
* @param see_all If true, all units are considered (and viewing_team is ignored).
*
* @return true iff a visible enemy exerts zone of control over loc.
*/
bool enemy_zoc(const team& current_team, const map_location& loc,
const team& viewing_team, bool see_all)
{
// Check the adjacent tiles.
for(const map_location& adj : get_adjacent_tiles(loc)) {
const unit *u = resources::gameboard->get_visible_unit(adj, viewing_team, see_all);
if ( u && current_team.is_enemy(u->side()) && u->emits_zoc() )
return true;
}
// No adjacent tiles had an enemy exerting ZoC over loc.
return false;
}
namespace {
/**
* Nodes used by find_routes().
* These store the information necessary for extending the path
* and for tracing the route back to the source.
*/
struct findroute_node {
int moves_left, turns_left;
map_location prev;
// search_num is used to detect which nodes have been collected
// in the current search. (More than just a boolean value so
// that nodes can be stored between searches.)
unsigned search_num;
// Constructors.
findroute_node(int moves, int turns, const map_location &prev_loc, unsigned search_count)
: moves_left(moves)
, turns_left(turns)
, prev(prev_loc)
, search_num(search_count)
{ }
findroute_node()
: moves_left(0)
, turns_left(0)
, prev()
, search_num(0)
{ }
// Compare these nodes based on movement consumed.
bool operator<(const findroute_node& o) const
{
return std::tie(turns_left, moves_left) > std::tie(o.turns_left, o.moves_left);
}
};
/**
* Converts map locations to and from integer indices.
*/
struct findroute_indexer {
int w, h; // Width and height of the map.
// Constructor:
findroute_indexer(int a, int b) : w(a), h(b) { }
// Convert to an index: (throws on out of bounds)
unsigned operator()(int x, int y) const {
VALIDATE(this->on_board(x,y),
"Pathfind: Location not on board");
return x + static_cast<unsigned>(y)*w;
}
unsigned operator()(const map_location& loc) const {
return (*this)(loc.x, loc.y);
}
// Convert from an index:
map_location operator()(unsigned index) const {
return map_location(
static_cast<int>(index%w),
static_cast<int>(index/w));
}
// Check if location is on board
inline bool on_board(const map_location& loc) const {
return this->on_board(loc.x, loc.y);
}
inline bool on_board(int x, int y) const {
return (x >= 0) && (x < w) && (y >= 0) && (y < h);
}
};
/**
* A function object for comparing indices.
*/
struct findroute_comp {
const std::vector<findroute_node>& nodes;
// Constructor:
findroute_comp(const std::vector<findroute_node>& n) : nodes(n) { }
// Binary predicate evaluating the order of its arguments:
bool operator()(int l, int r) const {
return nodes[r] < nodes[l];
}
};
}
/**
* Creates a list of routes that a unit can traverse from the provided location.
* (This is called when creating pathfind::paths and descendant classes.)
*
* @param[in] origin The location at which to begin the routes.
* @param[in] costs The costs to use for route finding.
* @param[in] slowed Whether or not to use the slowed costs.
* @param[in] moves_left The number of movement points left for the current turn.
* @param[in] max_moves The number of movement points in each future turn.
* @param[in] turns_left The number of future turns of movement to calculate.
* @param[out] destinations The traversable routes.
* @param[out] edges The hexes (possibly off-map) adjacent to those in
* destinations. (It is permissible for this to contain
* some hexes that are also in destinations.)
*
* @param[in] teleporter If not nullptr, teleportation will be considered, using
* this unit's abilities.
* @param[in] current_team If not nullptr, enemies of this team can obstruct routes
* both by occupying hexes and by exerting zones of control.
* In addition, the presence of units can affect
* teleportation options.
* @param[in] skirmisher If not nullptr, use this to determine where ZoC can and
* cannot be ignored (due to this unit having or not
* having the skirmisher ability).
* If nullptr, then ignore all zones of control.
* (No effect if current_team is nullptr).
* @param[in] viewing_team If not nullptr, use this team's vision when detecting
* enemy units and teleport destinations.
* If nullptr, then "see all".
* (No effect if teleporter and current_team are both nullptr.)
* @param[in] jamming_map The relevant "jamming" of the costs being used
* (currently only used with vision costs).
* @param[out] full_cost_map If not nullptr, build a cost_map instead of destinations.
* Destinations is ignored.
* full_cost_map is a vector of pairs. The first entry is the
* cost itself, the second how many units already visited this hex
* @param[in] check_vision If true, use vision check for teleports, that is, ignore
* units potentially blocking the teleport exit
*/
static void find_routes(
const map_location & origin, const movetype::terrain_costs & costs,
bool slowed, int moves_left, int max_moves, int turns_left,
paths::dest_vect & destinations, std::set<map_location> * edges,
const unit * teleporter, const team * current_team,
const unit * skirmisher, const team * viewing_team,
const std::map<map_location, int> * jamming_map=nullptr,
std::vector<std::pair<int, int>> * full_cost_map=nullptr, bool check_vision=false)
{
const gamemap& map = resources::gameboard->map();
const bool see_all = viewing_team == nullptr;
// When see_all is true, the viewing team never matters, but we still
// need to supply one to some functions.
if ( viewing_team == nullptr )
viewing_team = &resources::gameboard->teams().front();
// Build a teleport map, if needed.
const teleport_map teleports = teleporter ?
get_teleport_locations(*teleporter, *viewing_team, see_all, current_team == nullptr, check_vision) :
teleport_map();
// Since this is called so often, keep memory reserved for the node list.
static std::vector<findroute_node> nodes;
static unsigned search_counter = 0;
// Incrementing search_counter means we ignore results from earlier searches.
++search_counter;
// Whenever the counter cycles, trash the contents of nodes and restart at 1.
if ( search_counter == 0 ) {
nodes.resize(0);
search_counter = 1;
}
// Initialize the nodes for this search.
nodes.resize(static_cast<size_t>(map.w()) * map.h());
findroute_comp node_comp(nodes);
findroute_indexer index(map.w(), map.h());
assert(index.on_board(origin));
// Check if full_cost_map has the correct size.
// If not, ignore it. If yes, initialize the start position.
if ( full_cost_map ) {
if ( full_cost_map->size() != static_cast<unsigned>(map.w() * map.h()) )
full_cost_map = nullptr;
else {
if ( (*full_cost_map)[index(origin)].second == 0 )
(*full_cost_map)[index(origin)].first = 0;
(*full_cost_map)[index(origin)].second += 1;
}
}
// Used to optimize the final collection of routes.
int xmin = origin.x, xmax = origin.x, ymin = origin.y, ymax = origin.y;
int nb_dest = 1;
// Record the starting location.
nodes[index(origin)] = findroute_node(moves_left, turns_left,
map_location::null_location(),
search_counter);
// Begin the search at the starting location.
std::vector<unsigned> hexes_to_process(1, index(origin)); // Will be maintained as a heap.
while ( !hexes_to_process.empty() ) {
// Process the hex closest to the origin.
const unsigned cur_index = hexes_to_process.front();
const map_location cur_hex = index(cur_index);
const findroute_node& current = nodes[cur_index];
// Remove from the heap.
std::pop_heap(hexes_to_process.begin(), hexes_to_process.end(), node_comp);
hexes_to_process.pop_back();
// Get the locations adjacent to current.
std::vector<map_location> adj_locs(6);
get_adjacent_tiles(cur_hex, adj_locs.data());
// Sort adjacents by on-boardness
auto off_board_it = std::partition(adj_locs.begin(), adj_locs.end(), [&index](map_location loc){
return index.on_board(loc);
});
// Store off-board edges if needed
if(edges != nullptr){
edges->insert(off_board_it, adj_locs.end());
}
// Remove off-board map locations
adj_locs.erase(off_board_it, adj_locs.end());
if ( teleporter ) {
auto allowed_teleports = teleports.get_adjacents(cur_hex);
adj_locs.insert(adj_locs.end(), allowed_teleports.begin(), allowed_teleports.end());
}
for ( int i = adj_locs.size()-1; i >= 0; --i ) {
// Get the node associated with this location.
const map_location & next_hex = adj_locs[i];
const unsigned next_index = index(next_hex);
findroute_node & next = nodes[next_index];
// Skip nodes we have already collected.
// (Since no previously checked routes were longer than
// the current one, the current route cannot be shorter.)
// (Significant difference from classic Dijkstra: we have
// vertex weights, not edge weights.)
if ( next.search_num == search_counter )
continue;
// If we go to next, it will be from current.
next.prev = cur_hex;
// Calculate the cost of entering next_hex.
int cost = costs.cost(map[next_hex], slowed);
if ( jamming_map ) {
const std::map<map_location, int>::const_iterator jam_it =
jamming_map->find(next_hex);
if ( jam_it != jamming_map->end() )
cost += jam_it->second;
}
// Calculate movement remaining after entering next_hex.
next.moves_left = current.moves_left - cost;
next.turns_left = current.turns_left;
if ( next.moves_left < 0 ) {
// Have to delay until the next turn.
next.turns_left--;
next.moves_left = max_moves - cost;
}
if ( next.moves_left < 0 || next.turns_left < 0 ) {
// Either can never enter this hex or out of turns.
if ( edges != nullptr )
edges->insert(next_hex);
continue;
}
if ( current_team ) {
// Account for enemy units.
const unit *v = resources::gameboard->get_visible_unit(next_hex, *viewing_team, see_all);
if ( v && current_team->is_enemy(v->side()) ) {
// Cannot enter enemy hexes.
if ( edges != nullptr )
edges->insert(next_hex);
continue;
}
if ( skirmisher && next.moves_left > 0 &&
enemy_zoc(*current_team, next_hex, *viewing_team, see_all) &&
!skirmisher->get_ability_bool("skirmisher", next_hex) ) {
next.moves_left = 0;
}
}
if ( !see_all && viewing_team && current_team && viewing_team != current_team && viewing_team->shrouded(next_hex) ) {
// bug #2199: in "Show Enemy Moves", don't pathfind enemy units through the player's shroud
continue;
}
// Update full_cost_map
if ( full_cost_map ) {
if ( (*full_cost_map)[next_index].second == 0 )
(*full_cost_map)[next_index].first = 0;
int summed_cost = (turns_left - next.turns_left + 1) * max_moves - next.moves_left;
(*full_cost_map)[next_index].first += summed_cost;
(*full_cost_map)[next_index].second += 1;
}
// Mark next as being collected.
next.search_num = search_counter;
// Add this node to the heap.
hexes_to_process.push_back(next_index);
std::push_heap(hexes_to_process.begin(), hexes_to_process.end(), node_comp);
// Bookkeeping (for later).
++nb_dest;
if ( next_hex.x < xmin )
xmin = next_hex.x;
else if ( xmax < next_hex.x )
xmax = next_hex.x;
if ( next_hex.y < ymin )
ymin = next_hex.y;
else if ( ymax < next_hex.y )
ymax = next_hex.y;
}//for (i)
}//while (hexes_to_process)
// Currently the only caller who uses full_cost_map doesn't need the
// destinations. We can skip this part.
if ( full_cost_map ) {
return;
}
// Build the routes for every map_location that we reached.
// The ordering must be compatible with map_location::operator<.
destinations.reserve(nb_dest);
for (int x = xmin; x <= xmax; ++x) {
for (int y = ymin; y <= ymax; ++y)
{
const findroute_node &n = nodes[index(x,y)];
if ( n.search_num == search_counter ) {
paths::step s =
{ map_location(x,y), n.prev, n.moves_left + n.turns_left*max_moves };
destinations.push_back(s);
}
}
}
}
static bool step_compare(const paths::step& a, const map_location& b) {
return a.curr < b;
}
paths::dest_vect::const_iterator paths::dest_vect::find(const map_location &loc) const
{
const_iterator i = std::lower_bound(begin(), end(), loc, step_compare);
if (i != end() && i->curr != loc) return end();
return i;
}
void paths::dest_vect::insert(const map_location &loc)
{
iterator i = std::lower_bound(begin(), end(), loc, step_compare);
if (i != end() && i->curr == loc) return;
paths::step s { loc, map_location(), 0 };
std::vector<step>::insert(i, s);
}
/**
* Returns the path going from the source point (included) to the
* destination point @a j (excluded).
*/
std::vector<map_location> paths::dest_vect::get_path(const const_iterator &j) const
{
std::vector<map_location> path;
if (!j->prev.valid()) {
path.push_back(j->curr);
} else {
const_iterator i = j;
do {
i = find(i->prev);
assert(i != end());
path.push_back(i->curr);
} while (i->prev.valid());
}
std::reverse(path.begin(), path.end());
return path;
}
bool paths::dest_vect::contains(const map_location &loc) const
{
return find(loc) != end();
}
/**
* Construct a list of paths for the specified unit.
*
* This function is used for several purposes, including showing a unit's
* potential moves and generating currently possible paths.
* @param u The unit whose moves and movement type will be used.
* @param force_ignore_zoc Set to true to completely ignore zones of control.
* @param allow_teleport Set to true to consider teleportation abilities.
* @param viewing_team Usually the current team, except for "show enemy moves", etc.
* @param additional_turns The number of turns to account for, in addition to the current.
* @param see_all Set to true to remove unit visibility from consideration.
* @param ignore_units Set to true if units should never obstruct paths (implies ignoring ZoC as well).
*/
paths::paths(const unit& u, bool force_ignore_zoc,
bool allow_teleport, const team &viewing_team,
int additional_turns, bool see_all, bool ignore_units)
: destinations()
{
try {
find_routes(
u.get_location(),
u.movement_type().get_movement(),
u.get_state(unit::STATE_SLOWED),
u.movement_left(),
u.total_movement(),
additional_turns,
destinations,
nullptr,
allow_teleport ? &u : nullptr,
ignore_units ? nullptr : &resources::gameboard->get_team(u.side()),
force_ignore_zoc ? nullptr : &u,
see_all ? nullptr : &viewing_team
);
} catch(const std::out_of_range&) {
// Invalid unit side.
}
}
/**
* Virtual destructor to support child classes.
*/
paths::~paths()
{
}
/**
* Constructs a list of vision paths for a unit.
*
* This is used to construct a list of hexes that the indicated unit can see.
* It differs from pathfinding in that it will only ever go out one turn,
* and that it will also collect a set of border hexes (the "one hex beyond"
* movement to which vision extends).
* @param viewer The unit doing the viewing.
* @param loc The location from which the viewing occurs
* (does not have to be the unit's location).
* @param jamming_map The relevant "jamming" of the costs being used.
*/
vision_path::vision_path(const unit& viewer, const map_location& loc,
const std::map<map_location, int>& jamming_map)
: paths(), edges()
{
const int sight_range = viewer.vision();
// The three nullptr parameters indicate (in order):
// ignore units, ignore ZoC (no effect), and don't build a cost_map.
// The viewing team needs to be the unit's team here.
const team& viewing_team = resources::gameboard->get_team(viewer.side());
find_routes(loc, viewer.movement_type().get_vision(),
viewer.get_state(unit::STATE_SLOWED), sight_range, sight_range,
0, destinations, &edges, &viewer, nullptr, nullptr, &viewing_team, &jamming_map, nullptr, true);
}
/**
* Constructs a list of vision paths for a unit.
*
* This constructor is provided so that only the relevant portion of a unit's
* data is required to construct the vision paths.
* @param view_costs The vision costs of the unit doing the viewing.
* @param slowed Whether or not the unit is slowed.
* @param sight_range The vision() of the unit.
* @param loc The location from which the viewing occurs
* (does not have to be the unit's location).
* @param jamming_map The relevant "jamming" of the costs being used.
*/
vision_path::vision_path(const movetype::terrain_costs & view_costs, bool slowed,
int sight_range, const map_location & loc,
const std::map<map_location, int>& jamming_map)
: paths(), edges()
{
// The three nullptr parameters indicate (in order):
// ignore units, ignore ZoC (no effect), and don't build a cost_map.
const unit_map::const_iterator u = resources::gameboard->units().find(loc);
if(u.valid())
{
// The viewing team needs to be the unit's team here.
const team& viewing_team = resources::gameboard->get_team(u->side());
find_routes(loc, view_costs, slowed, sight_range, sight_range, 0,
destinations, &edges, &*u, nullptr, nullptr, &viewing_team, &jamming_map, nullptr, true);
}
else
{
find_routes(loc, view_costs, slowed, sight_range, sight_range, 0,
destinations, &edges, nullptr, nullptr, nullptr, nullptr, &jamming_map, nullptr, true);
}
}
/** Default destructor */
vision_path::~vision_path()
{
}
/**
* Constructs a list of jamming paths for a unit.
*
* This is used to construct a list of hexes that the indicated unit can jam.
* It differs from pathfinding in that it will only ever go out one turn.
* @param jammer The unit doing the jamming.
* @param loc The location from which the jamming occurs
* (does not have to be the unit's location).
*/
jamming_path::jamming_path(const unit& jammer, const map_location& loc)
: paths()
{
const int jamming_range = jammer.jamming();
// The five nullptr parameters indicate (in order): no edges, no teleports,
// ignore units, ignore ZoC (no effect), and see all (no effect).
find_routes(loc, jammer.movement_type().get_jamming(),
jammer.get_state(unit::STATE_SLOWED), jamming_range, jamming_range,
0, destinations, nullptr, nullptr, nullptr, nullptr, nullptr);
}
/** Default destructor */
jamming_path::~jamming_path()
{
}
marked_route mark_route(const plain_route &rt, bool update_move_cost)
{
marked_route res;
if (rt.steps.empty()) return marked_route();
res.route = rt;
unit_map::const_iterator it = resources::gameboard->units().find(rt.steps.front());
if (it == resources::gameboard->units().end()) return marked_route();
const unit& u = *it;
int turns = 0;
int total_costs = 0;
int movement = u.movement_left();
const team& unit_team = resources::gameboard->get_team(u.side());
bool zoc = false;
std::vector<map_location>::const_iterator i = rt.steps.begin();
for (; i !=rt.steps.end(); ++i) {
bool last_step = (i+1 == rt.steps.end());
// move_cost of the next step is irrelevant for the last step
assert(last_step || resources::gameboard->map().on_board(*(i+1)));
const int move_cost = last_step ? 0 : u.movement_cost(static_cast<const game_board*>(resources::gameboard)->map()[*(i+1)]);
const team& viewing_team = display::get_singleton()->viewing_team();
if (last_step || zoc || move_cost > movement) {
// check if we stop an a village and so maybe capture it
// if it's an enemy unit and a fogged village, we assume a capture
// (if he already owns it, we can't know that)
// if it's not an enemy, we can always know if he owns the village
bool capture = resources::gameboard->map().is_village(*i) && ( !unit_team.owns_village(*i)
|| (viewing_team.is_enemy(u.side()) && viewing_team.fogged(*i)) );
++turns;
bool invisible = u.invisible(*i, false);
res.marks[*i] = marked_route::mark(turns, zoc, capture, invisible);
if(last_step) {
if(capture) {
total_costs += movement;
}
break; // finished and we used dummy move_cost
}
total_costs += movement;
movement = u.total_movement();
if(move_cost > movement) {
return res; //we can't reach destination
}
}
zoc = enemy_zoc(unit_team, *(i + 1), viewing_team)
&& !u.get_ability_bool("skirmisher", *(i+1));
if (zoc) {
total_costs += movement;
movement = 0;
} else {
movement -= move_cost;
total_costs += move_cost;
}
}
if(update_move_cost) {
res.move_cost = total_costs;
}
return res;
}
shortest_path_calculator::shortest_path_calculator(const unit& u, const team& t,
const std::vector<team>& teams, const gamemap& map,
bool ignore_unit, bool ignore_defense, bool see_all)
: unit_(u), viewing_team_(t), teams_(teams), map_(map),
movement_left_(unit_.movement_left()),
total_movement_(unit_.total_movement()),
ignore_unit_(ignore_unit), ignore_defense_(ignore_defense),
see_all_(see_all)
{}
double shortest_path_calculator::cost(const map_location& loc, const double so_far) const
{
assert(map_.on_board(loc));
// loc is shrouded, consider it impassable
// NOTE: This is why AI must avoid to use shroud
if (!see_all_ && viewing_team_.shrouded(loc))
return getNoPathValue();
const t_translation::terrain_code terrain = map_[loc];
const int terrain_cost = unit_.movement_cost(terrain);
// Pathfinding heuristic: the cost must be at least 1
VALIDATE(terrain_cost >= 1, _("Terrain with a movement cost less than 1 encountered."));
// Compute how many movement points are left in the game turn
// needed to reach the previous hex.
// total_movement_ is not zero, thanks to the pathfinding heuristic
int remaining_movement = movement_left_ - static_cast<int>(so_far);
if (remaining_movement < 0) {
remaining_movement = total_movement_ - (-remaining_movement) % total_movement_;
}
if (terrain_cost >= movetype::UNREACHABLE || (total_movement_ < terrain_cost && remaining_movement < terrain_cost)) {
return getNoPathValue();
}
int other_unit_subcost = 0;
if (!ignore_unit_) {
const unit *other_unit =
resources::gameboard->get_visible_unit(loc, viewing_team_, see_all_);
// We can't traverse visible enemy and we also prefer empty hexes
// (less blocking in multi-turn moves and better when exploring fog,
// because we can't stop on a friend)
if (other_unit)
{
if (teams_[unit_.side() - 1].is_enemy(other_unit->side()))
return getNoPathValue();
else
// This value will be used with the defense_subcost (see below)
// The 1 here means: consider occupied hex as a -1% defense
// (less important than 10% defense because friends may move)
other_unit_subcost = 1;
}
}
// this will sum all different costs of this move
int move_cost = 0;
// Suppose that we have only 2 remaining MP and want to move onto a hex
// costing 3 MP. We don't have enough MP now, so we must end our turn here,
// thus spend our remaining MP by waiting (next turn, with full MP, we will
// be able to move on that hex)
if (remaining_movement < terrain_cost) {
move_cost += remaining_movement;
remaining_movement = total_movement_; // we consider having full MP now
}
// check ZoC
if (!ignore_unit_ && remaining_movement != terrain_cost
&& enemy_zoc(teams_[unit_.side()-1], loc, viewing_team_, see_all_)
&& !unit_.get_ability_bool("skirmisher", loc)) {
// entering ZoC cost all remaining MP
move_cost += remaining_movement;
} else {
// empty hex, pay only the terrain cost
move_cost += terrain_cost;
}
// We will add a tiny cost based on terrain defense, so the pathfinding
// will prefer good terrains between 2 with the same MP cost
// Keep in mind that defense_modifier is inverted (= 100 - defense%)
const int defense_subcost = ignore_defense_ ? 0 : unit_.defense_modifier(terrain);
// We divide subcosts by 100 * 100, because defense is 100-based and
// we don't want any impact on move cost for less then 100-steps path
// (even ~200 since mean defense is around ~50%)
return move_cost + (defense_subcost + other_unit_subcost) / 10000.0;
}
move_type_path_calculator::move_type_path_calculator(const movetype& mt, int movement_left, int total_movement, const team& t, const gamemap& map)
: movement_type_(mt), movement_left_(movement_left),
total_movement_(total_movement), viewing_team_(t), map_(map)
{}
// This is an simplified version of shortest_path_calculator (see above for explanation)
double move_type_path_calculator::cost(const map_location& loc, const double so_far) const
{
assert(map_.on_board(loc));
if (viewing_team_.shrouded(loc))
return getNoPathValue();
const t_translation::terrain_code terrain = map_[loc];
const int terrain_cost = movement_type_.movement_cost(terrain);
if (total_movement_ < terrain_cost)
return getNoPathValue();
int remaining_movement = movement_left_ - static_cast<int>(so_far);
if (remaining_movement < 0)
remaining_movement = total_movement_ - (-remaining_movement) % total_movement_;
int move_cost = 0;
if (remaining_movement < terrain_cost) {
move_cost += remaining_movement;
}
move_cost += terrain_cost;
return move_cost;
}
emergency_path_calculator::emergency_path_calculator(const unit& u, const gamemap& map)
: unit_(u), map_(map)
{}
double emergency_path_calculator::cost(const map_location& loc, const double) const
{
assert(map_.on_board(loc));
return unit_.movement_cost(map_[loc]);
}
dummy_path_calculator::dummy_path_calculator(const unit&, const gamemap&)
{}
double dummy_path_calculator::cost(const map_location&, const double) const
{
return 1.0;
}
/**
* Constructs a cost-map. For a unit each hex is mapped to the cost the
* unit will need to reach this hex. Considers movement-loss caused by
* turn changes.
* Can also used with multiple units to accumulate their costs efficiently.
* Will also count how many units could reach a hex for easy normalization.
* @param u the unit
* @param force_ignore_zoc Set to true to completely ignore zones of control.
* @param allow_teleport Set to true to consider teleportation abilities.
* @param viewing_team Usually the current team, except for "show enemy moves", etc.
* @param see_all Set to true to remove unit visibility from consideration.
* @param ignore_units Set to true if units should never obstruct paths (implies ignoring ZoC as well).
*/
full_cost_map::full_cost_map(const unit& u, bool force_ignore_zoc,
bool allow_teleport, const team &viewing_team,
bool see_all, bool ignore_units)
:force_ignore_zoc_(force_ignore_zoc), allow_teleport_(allow_teleport),
viewing_team_(viewing_team), see_all_(see_all), ignore_units_(ignore_units)
{
const gamemap& map = resources::gameboard->map();
cost_map = std::vector<std::pair<int, int>>(static_cast<size_t>(map.w()) * map.h(), std::pair(-1, 0));
add_unit(u);
}
/**
* Same as other constructor but without unit. Use this when working
* with add_unit().
*/
full_cost_map::full_cost_map(bool force_ignore_zoc,
bool allow_teleport, const team &viewing_team,
bool see_all, bool ignore_units)
:force_ignore_zoc_(force_ignore_zoc), allow_teleport_(allow_teleport),
viewing_team_(viewing_team), see_all_(see_all), ignore_units_(ignore_units)
{
const gamemap& map = resources::gameboard->map();
cost_map = std::vector<std::pair<int, int>>(static_cast<size_t>(map.w()) * map.h(), std::pair(-1, 0));
}
/**
* Adds a units cost map to cost_map (increments the elements in cost_map)
* @param u a real existing unit on the map
* @param use_max_moves whether to use the unit's max movement or the unit's remaining movement
*/
void full_cost_map::add_unit(const unit& u, bool use_max_moves)
{
try {
// We don't need the destinations, but find_routes() wants to have this parameter
paths::dest_vect dummy = paths::dest_vect();
find_routes(
u.get_location(),
u.movement_type().get_movement(),
u.get_state(unit::STATE_SLOWED),
(use_max_moves) ? u.total_movement() : u.movement_left(),
u.total_movement(),
99,
dummy,
nullptr,
allow_teleport_ ? &u : nullptr,
ignore_units_ ? nullptr : &resources::gameboard->get_team(u.side()),
force_ignore_zoc_ ? nullptr : &u,
see_all_ ? nullptr : &viewing_team_,
nullptr,
&cost_map
);
} catch(const std::out_of_range&) {
// Invalid unit side.
}
}
/**
* Adds a units cost map to cost_map (increments the elements in cost_map)
* This function can be used to generate a cost_map with a non existing unit.
* @param origin the location on the map from where the calculations shall start
* @param ut the unit type we are interested in
* @param side the side of the unit. Important for zocs.
*/
void full_cost_map::add_unit(const map_location& origin, const unit_type* const ut, int side)
{
if (!ut) {
return;
}
unit_ptr u = unit::create(*ut, side, false);
u->set_location(origin);
add_unit(*u);
}
/**
* Accessor for the cost/reach-amount pairs.
* Read comment in pathfind.hpp to cost_map.
*
* @return the entry of the cost_map at (x, y)
* or (-1, 0) if value is not set or (x, y) is invalid.
*/
std::pair<int, int> full_cost_map::get_pair_at(map_location loc) const
{
const gamemap& map = resources::gameboard->map();
assert(cost_map.size() == static_cast<unsigned>(map.w() * map.h()));
if (!map.on_board(loc)) {
return std::pair(-1, 0); // invalid
}
return cost_map[loc.x + (loc.y * map.w())];
}
/**
* Accessor for the costs.
*
* @return the value of the cost_map at (x, y)
* or -1 if value is not set or (x, y) is invalid.
*/
int full_cost_map::get_cost_at(map_location loc) const
{
return get_pair_at(loc).first;
}
/**
* Accessor for the costs.
*
* @return The average cost of all added units for this hex
* or -1 if no unit can reach the hex.
*/
double full_cost_map::get_average_cost_at(map_location loc) const
{