2 * Empire - A multi-player, client/server Internet based war game.
3 * Copyright (C) 1986-2014, Dave Pare, Jeff Bailey, Thomas Ruschak,
4 * Ken Stevens, Steve McClure, Markus Armbruster
6 * Empire is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 3 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 General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
21 * See files README, COPYING and CREDITS in the root of the source
22 * tree for related information and legal notices. It is expected
23 * that future projects/authors will amend these files as needed.
27 * shpsub.c: Ship subroutine stuff
29 * Known contributors to this file:
31 * Steve McClure, 1996-2000
32 * Markus Armbruster, 2006-2014
50 #include "prototypes.h"
56 static void shp_nav_put_one(struct ulist *);
57 static int shp_check_one_mines(struct ulist *);
58 static int shp_hit_mine(struct shpstr *);
59 static void shp_stays(natid, char *, struct ulist *);
62 shp_sel(struct nstr_item *ni, struct emp_qelem *list)
67 while (nxtitem(ni, &ship)) {
69 * It would be nice to let deities navigate foreign ships, but
70 * much of the code assumes that only the ship's owner can
73 if (!ship.shp_own || ship.shp_own != player->cnum)
76 if (ontradingblock(EF_SHIP, &ship)) {
77 pr("ship #%d inelligible - it's for sale.\n",
84 memset(ship.shp_rpath, 0, sizeof(ship.shp_rpath));
85 putship(ship.shp_uid, &ship);
86 shp_insque(&ship, list);
92 * Return the new list link.
95 shp_insque(struct shpstr *sp, struct emp_qelem *list)
97 struct ulist *mlp = malloc(sizeof(struct ulist));
100 mlp->mobil = sp->shp_mobil;
101 emp_insque(&mlp->queue, list);
105 /* This function assumes that the list was created by shp_sel */
107 shp_nav(struct emp_qelem *list, double *minmobp, double *maxmobp,
110 struct emp_qelem *qp;
111 struct emp_qelem *next;
113 struct shpstr *sp, *flg = NULL;
118 for (qp = list->q_back; qp != list; qp = next) {
120 mlp = (struct ulist *)qp;
121 sp = &mlp->unit.ship;
122 getship(sp->shp_uid, sp);
123 if (sp->shp_own != actor) {
124 mpr(actor, "%s was sunk at %s\n",
125 prship(sp), xyas(sp->shp_x, sp->shp_y, actor));
126 emp_remque(&mlp->queue);
130 /* check crew - uws don't count */
131 if (sp->shp_item[I_MILIT] == 0 && sp->shp_item[I_CIVIL] == 0) {
132 shp_stays(actor, "is crewless", mlp);
135 if (!getsect(sp->shp_x, sp->shp_y, §)) {
136 shp_stays(actor, "was sucked into the sky by a strange looking spaceship", mlp); /* heh -KHS */
139 switch (shp_check_nav(sp, §)) {
142 case SHP_STUCK_CONSTRUCTION:
143 shp_stays(actor, "is caught in a construction zone", mlp);
148 case SHP_STUCK_CANAL:
149 case SHP_STUCK_IMPASSABLE:
150 shp_stays(actor, "is landlocked", mlp);
155 else if (sp->shp_x != flg->shp_x || sp->shp_y != flg->shp_y) {
156 shp_stays(actor, "is not with the flagship", mlp);
159 if (sp->shp_mobil + 1 < (int)mlp->mobil) {
160 mlp->mobil = sp->shp_mobil;
162 if (mlp->mobil < *minmobp)
163 *minmobp = mlp->mobil;
164 if (mlp->mobil > *maxmobp)
165 *maxmobp = mlp->mobil;
170 shp_nav_put(struct emp_qelem *list, natid actor)
172 struct emp_qelem *qp, *next;
176 for (qp = list->q_back; qp != list; qp = next) {
178 mlp = (struct ulist *)qp;
179 sp = &mlp->unit.ship;
180 mpr(actor, "%s stopped at %s\n",
181 prship(sp), xyas(sp->shp_x, sp->shp_y, actor));
182 shp_nav_put_one(mlp);
187 shp_nav_put_one(struct ulist *mlp)
189 mlp->unit.ship.shp_mobil = (int)mlp->mobil;
190 putship(mlp->unit.ship.shp_uid, &mlp->unit.ship);
191 emp_remque(&mlp->queue);
196 shp_sweep(struct emp_qelem *ship_list, int verbose, int takemob, natid actor)
198 struct emp_qelem *qp;
199 struct emp_qelem *next;
202 int mines, m, max, shells;
206 for (qp = ship_list->q_back; qp != ship_list; qp = next) {
208 mlp = (struct ulist *)qp;
209 if (!(mchr[mlp->unit.ship.shp_type].m_flags & M_SWEEP)) {
211 mpr(actor, "%s doesn't have minesweeping capability!\n",
212 prship(&mlp->unit.ship));
215 if (takemob && mlp->mobil <= 0.0) {
217 mpr(actor, "%s is out of mobility!\n",
218 prship(&mlp->unit.ship));
221 getsect(mlp->unit.ship.shp_x, mlp->unit.ship.shp_y, §);
222 if (sect.sct_type != SCT_WATER) {
224 mpr(actor, "%s is not at sea. No mines there!\n",
225 prship(&mlp->unit.ship));
229 mlp->mobil -= shp_mobcost(&mlp->unit.ship);
230 mlp->unit.ship.shp_mobil = (int)mlp->mobil;
232 putship(mlp->unit.ship.shp_uid, &mlp->unit.ship);
233 if (!(mines = sect.sct_mines))
235 max = mchr[mlp->unit.ship.shp_type].m_item[I_SHELL];
236 shells = mlp->unit.ship.shp_item[I_SHELL];
237 for (m = 0; mines > 0 && m < 5; m++) {
239 mpr(actor, "Sweep...\n");
241 shells = MIN(max, shells + 1);
242 changed |= map_set(actor, sect.sct_x, sect.sct_y, 'X', 0);
245 sect.sct_mines = mines;
246 mlp->unit.ship.shp_item[I_SHELL] = shells;
247 putship(mlp->unit.ship.shp_uid, &mlp->unit.ship);
249 if (shp_check_one_mines(mlp)) {
261 shp_check_one_mines(struct ulist *mlp)
266 getsect(mlp->unit.ship.shp_x, mlp->unit.ship.shp_y, §);
267 if (sect.sct_type != SCT_WATER)
271 if (chance(DMINE_HITCHANCE(sect.sct_mines))) {
272 actor = mlp->unit.ship.shp_own;
273 shp_hit_mine(&mlp->unit.ship);
275 if (map_set(actor, sect.sct_x, sect.sct_y, 'X', 0))
278 putship(mlp->unit.ship.shp_uid, &mlp->unit.ship);
279 if (!mlp->unit.ship.shp_own)
286 shp_check_mines(struct emp_qelem *ship_list)
288 struct emp_qelem *qp;
289 struct emp_qelem *next;
293 for (qp = ship_list->q_back; qp != ship_list; qp = next) {
295 mlp = (struct ulist *)qp;
296 if (shp_check_one_mines(mlp)) {
307 shp_stays(natid actor, char *str, struct ulist *mlp)
309 mpr(actor, "%s %s & stays in %s\n",
310 prship(&mlp->unit.ship), str,
311 xyas(mlp->unit.ship.shp_x, mlp->unit.ship.shp_y, actor));
312 shp_nav_put_one(mlp);
316 * Return whether and why SP would be stuck in SECTP.
319 shp_check_nav(struct shpstr *sp, struct sctstr *sectp)
321 switch (dchr[sectp->sct_type].d_nav) {
325 if (!(mchr[sp->shp_type].m_flags & M_CANAL)) {
326 return SHP_STUCK_CANAL;
330 if (sectp->sct_effic < 2)
331 return SHP_STUCK_CONSTRUCTION;
334 if (sectp->sct_effic < 60)
335 return SHP_STUCK_CONSTRUCTION;
341 return SHP_STUCK_IMPASSABLE;
343 return SHP_STUCK_NOT;
347 sect_has_dock(struct sctstr *sect)
349 switch (dchr[sect->sct_type].d_nav) {
359 shp_count(struct emp_qelem *list, int wantflags, int nowantflags,
362 struct emp_qelem *qp;
363 struct emp_qelem *next;
367 for (qp = list->q_back; qp != list; qp = next) {
369 mlp = (struct ulist *)qp;
370 if (mlp->unit.ship.shp_x != x || mlp->unit.ship.shp_y != y)
373 (mchr[mlp->unit.ship.shp_type].m_flags & wantflags) != wantflags)
376 mchr[mlp->unit.ship.shp_type].m_flags & nowantflags)
384 shp_damage_one(struct ulist *mlp, int dam)
386 /* ship might have changed (launched interceptors, missile defense) */
387 getship(mlp->unit.ship.shp_uid, &mlp->unit.ship);
388 shipdamage(&mlp->unit.ship, dam);
389 putship(mlp->unit.ship.shp_uid, &mlp->unit.ship);
390 if (!mlp->unit.ship.shp_own) {
391 emp_remque(&mlp->queue);
397 shp_damage(struct emp_qelem *list, int totdam, int wantflags,
398 int nowantflags, int x, int y)
400 struct emp_qelem *qp;
401 struct emp_qelem *next;
407 || !(count = shp_count(list, wantflags, nowantflags, x, y)))
409 dam = ldround((double)totdam / count, 1);
410 for (qp = list->q_back; qp != list; qp = next) {
412 mlp = (struct ulist *)qp;
413 if (mlp->unit.ship.shp_x != x || mlp->unit.ship.shp_y != y)
416 (mchr[mlp->unit.ship.shp_type].m_flags & wantflags) != wantflags)
419 mchr[mlp->unit.ship.shp_type].m_flags & nowantflags)
421 shp_damage_one(mlp, dam);
427 shp_contains(struct emp_qelem *list, int newx, int newy, int wantflags,
430 struct emp_qelem *qp;
431 struct emp_qelem *next;
434 for (qp = list->q_back; qp != list; qp = next) {
436 mlp = (struct ulist *)qp;
437 /* If the ship isn't in the requested sector, then continue */
438 if (newx != mlp->unit.ship.shp_x || newy != mlp->unit.ship.shp_y)
441 (mchr[mlp->unit.ship.shp_type].m_flags & wantflags) != wantflags)
444 mchr[mlp->unit.ship.shp_type].m_flags & nowantflags)
451 static struct ulist *
452 most_valuable_ship(struct emp_qelem *list, coord x, coord y)
454 struct emp_qelem *qp;
455 struct emp_qelem *next;
457 struct ulist *mvs = NULL;
459 for (qp = list->q_back; qp != list; qp = next) {
461 mlp = (struct ulist *)qp;
462 if (mlp->unit.ship.shp_x != x || mlp->unit.ship.shp_y != y)
464 if (mchr[mlp->unit.ship.shp_type].m_flags & M_SUB)
466 if (!mchr[mlp->unit.ship.shp_type].m_nxlight &&
467 !mchr[mlp->unit.ship.shp_type].m_nchoppers &&
468 mchr[mlp->unit.ship.shp_type].m_cost < 1000 &&
469 !mchr[mlp->unit.ship.shp_type].m_nplanes &&
470 !mchr[mlp->unit.ship.shp_type].m_nland)
476 if (mchr[mlp->unit.ship.shp_type].m_cost * mlp->unit.ship.shp_effic >
477 mchr[mvs->unit.ship.shp_type].m_cost * mvs->unit.ship.shp_effic)
484 shp_easiest_target(struct emp_qelem *list, int wantflags, int nowantflags)
486 struct emp_qelem *qp;
487 struct emp_qelem *next;
490 int easiest = 9876; /* things start great for victim */
493 for (qp = list->q_back; qp != list; qp = next) {
495 mlp = (struct ulist *)qp;
497 (mchr[mlp->unit.ship.shp_type].m_flags & wantflags) != wantflags)
500 mchr[mlp->unit.ship.shp_type].m_flags & nowantflags)
502 hard = shp_hardtarget(&mlp->unit.ship);
504 easiest = hard; /* things get worse for victim */
507 return easiest - count;
511 shp_missile_interdiction(struct emp_qelem *list, coord newx, coord newy,
516 struct emp_qelem msl_list, *qp, *newqp;
520 mvs = most_valuable_ship(list, newx, newy);
524 msl_sel(&msl_list, newx, newy, victim, P_T | P_MAR, 0, MI_INTERDICT);
526 for (qp = msl_list.q_back; qp != &msl_list; qp = newqp) {
528 plp = (struct plist *)qp;
530 if (mvs && mission_pln_equip(plp, NULL, 'p') >= 0) {
531 if (msl_launch(&plp->plane, EF_SHIP, prship(&mvs->unit.ship),
532 newx, newy, victim, &sublaunch) < 0)
535 if (msl_hit(&plp->plane,
536 shp_hardtarget(&mvs->unit.ship), EF_SHIP,
537 N_SHP_MISS, N_SHP_SMISS, sublaunch, victim)) {
538 dam = pln_damage(&plp->plane, 'p', 1);
540 "missile interdiction mission does %d damage to %s!\n",
541 dam, prship(&mvs->unit.ship));
542 shp_damage_one(mvs, dam);
544 dam = pln_damage(&plp->plane, 'p', 0);
545 collateral_damage(newx, newy, dam);
547 mvs = most_valuable_ship(list, newx, newy);
549 plp->plane.pln_effic = 0;
550 putplane(plp->plane.pln_uid, &plp->plane);
559 /* Note that this function has a side effect - it uses coastwatch
560 * ranges to see if it should fire upon a ship. So, this function
561 * is expected to return positive if a ship is in range, and 0 if a
562 * ship is not in range. */
564 notify_coastguard(struct emp_qelem *list, int trange, struct sctstr *sectp)
566 struct emp_qelem *qp;
567 struct emp_qelem *next;
572 natp = getnatp(sectp->sct_own);
574 vrange = sectp->sct_type == SCT_RADAR ? 14 : 4;
575 vrange *= tfact(sectp->sct_own, 1.0) * sectp->sct_effic / 100.0;
583 for (qp = list->q_back; qp != list; qp = next) {
585 mlp = (struct ulist *)qp;
586 if (mchr[mlp->unit.ship.shp_type].m_flags & M_SUB)
588 if (natp->nat_flags & NF_COASTWATCH)
589 wu(0, sectp->sct_own,
590 "%s %s sighted at %s\n",
591 cname(mlp->unit.ship.shp_own),
592 prship(&mlp->unit.ship),
593 xyas(mlp->unit.ship.shp_x, mlp->unit.ship.shp_y,
596 setcont(sectp->sct_own, mlp->unit.ship.shp_own, FOUND_COAST);
603 shp_fort_interdiction(struct emp_qelem *list, coord newx, coord newy,
612 signed char notified[MAXNOC];
615 /* Inform neutral and worse */
616 for (i = 0; i < MAXNOC; ++i) {
617 if (relations_with(i, victim) <= NEUTRAL)
623 snxtsct_dist(&ns, newx, newy, fort_max_interdiction_range);
624 while (nxtsct(&ns, &fsect)) {
627 if (fsect.sct_own == victim)
629 if (notified[fsect.sct_own])
631 trange = mapdist(newx, newy, fsect.sct_x, fsect.sct_y);
632 if (notify_coastguard(list, trange, &fsect))
633 notified[fsect.sct_own] = 1;
635 if (opt_NO_FORT_FIRE)
636 return 0; /* Only coastwatch notify in nofortfire */
637 /* Only fire at Hostile ships */
638 for (i = 0; i < MAXNOC; ++i) {
639 if (relations_with(i, victim) >= NEUTRAL)
642 snxtsct_dist(&ns, newx, newy, fort_max_interdiction_range);
643 while (nxtsct(&ns, &fsect)) {
644 if (!notified[fsect.sct_own])
646 range = roundrange(fortrange(&fsect));
647 trange = mapdist(newx, newy, fsect.sct_x, fsect.sct_y);
650 dam = fort_fire(&fsect);
656 mpr(victim, "Incoming fire does %d damage!\n", dam);
658 mpr(victim, "%s fires at you for %d!\n",
659 xyas(fsect.sct_x, fsect.sct_y, victim), dam);
662 "%s fires at %s ships in %s for %d!\n",
663 xyas(fsect.sct_x, fsect.sct_y,
665 cname(victim), xyas(newx, newy, fsect.sct_own), dam);
666 nreport(fsect.sct_own, N_SHP_SHELL, victim, 1);
669 shp_damage(list, totdam, 0, M_SUB, newx, newy);
674 shp_mission_interdiction(struct emp_qelem *list, coord x, coord y,
675 natid victim, int subs)
677 char *what = subs ? "subs" : "ships";
678 int wantflags = subs ? M_SUB : 0;
679 int nowantflags = subs ? 0 : M_SUB;
680 int mission = subs ? MI_SINTERDICT : MI_INTERDICT;
683 dam = unit_interdict(x, y, victim, what,
684 shp_easiest_target(list, wantflags, nowantflags),
687 shp_damage(list, dam, wantflags, nowantflags, x, y);
692 shp_interdict(struct emp_qelem *list, coord newx, coord newy, natid victim)
696 if (shp_contains(list, newx, newy, 0, M_SUB)) {
697 stopping |= shp_fort_interdiction(list, newx, newy, victim);
699 if (shp_contains(list, newx, newy, 0, M_SUB)) {
700 stopping |= shp_mission_interdiction(list, newx, newy, victim, 0);
701 stopping |= shp_missile_interdiction(list, newx, newy, victim);
704 if (shp_contains(list, newx, newy, M_SUB, 0))
705 stopping |= shp_mission_interdiction(list, newx, newy, victim, 1);
709 /* high value of hardtarget is harder to hit */
711 shp_hardtarget(struct shpstr *sp)
715 struct mchrstr *mcp = mchr + sp->shp_type;
718 getsect(sp->shp_x, sp->shp_y, §);
719 onsea = sect.sct_type == SCT_WATER;
720 if (mcp->m_flags & M_SUB)
722 return (int)((sp->shp_effic / 100.0) *
723 (20 + shp_speed(sp) * onsea / 2.0 - vis));
727 shp_hit_mine(struct shpstr *sp)
731 mpr(sp->shp_own, "Kawhomp! Mine detected in %s!\n",
732 xyas(sp->shp_x, sp->shp_y, sp->shp_own));
734 nreport(sp->shp_own, N_HIT_MINE, 0, 1);
737 if (mchr[sp->shp_type].m_flags & M_SWEEP)
740 shipdamage(sp, ldround(m, 1));
746 shp_nav_one_sector(struct emp_qelem *list, int dir, natid actor)
749 struct emp_qelem *qp;
750 struct emp_qelem *next;
757 enum shp_stuck stuck;
762 if (CANT_HAPPEN(QEMPTY(list)))
765 if (dir <= DIR_STOP || dir >= DIR_VIEW) {
766 shp_nav_put(list, actor);
772 mlp = (struct ulist *)list->q_back;
773 newx = xnorm(mlp->unit.ship.shp_x + dx);
774 newy = ynorm(mlp->unit.ship.shp_y + dy);
775 getsect(newx, newy, §);
777 if (sect.sct_own && relations_with(sect.sct_own, actor) < FRIENDLY) {
778 mpr(actor, "can't go to %s\n", xyas(newx, newy, actor));
783 for (qp = list->q_back; qp != list; qp = next) {
785 mlp = (struct ulist *)qp;
786 switch (shp_check_nav(&mlp->unit.ship, §)) {
790 case SHP_STUCK_CANAL:
795 case SHP_STUCK_CONSTRUCTION:
796 case SHP_STUCK_IMPASSABLE:
797 mpr(actor, "can't go to %s\n", xyas(newx, newy, actor));
802 mpr(actor, "is too large to fit into the canal system at %s\n",
803 xyas(newx, newy, actor));
807 for (qp = list->q_back; qp != list; qp = next) {
809 mlp = (struct ulist *)qp;
810 stuck = shp_check_nav(&mlp->unit.ship, §);
811 if (stuck == SHP_STUCK_CANAL) {
813 "is too large to fit into the canal system at %s",
814 xyas(newx, newy, actor));
815 shp_stays(actor, dp, mlp);
817 } else if (CANT_HAPPEN(stuck != SHP_STUCK_NOT)) {
818 sprintf(dp, "can't go to %s", xyas(newx, newy, actor));
819 shp_stays(actor, dp, mlp);
823 if (mlp->mobil <= 0.0) {
824 shp_stays(actor, "is out of mobility", mlp);
827 mobcost = shp_mobcost(&mlp->unit.ship);
828 mlp->unit.ship.shp_x = newx;
829 mlp->unit.ship.shp_y = newy;
830 if (mlp->mobil - mobcost < -127) {
833 mlp->mobil -= mobcost;
835 mlp->unit.ship.shp_mobil = (int)mlp->mobil;
836 putship(mlp->unit.ship.shp_uid, &mlp->unit.ship);
838 /* Now update the map for this ship */
839 rad_map_set(mlp->unit.ship.shp_own,
840 mlp->unit.ship.shp_x, mlp->unit.ship.shp_y,
841 mlp->unit.ship.shp_effic, mlp->unit.ship.shp_tech,
842 mchr[mlp->unit.ship.shp_type].m_vrnge);
846 stopping |= shp_sweep(list, 0, 0, actor);
849 stopping |= shp_check_mines(list);
852 stopping |= shp_interdict(list, newx, newy, actor);
859 * Check for incoming missiles with a P_MAR flag.
860 * Return True=1 if the missile was shotdown.
863 * Chad Zabel, July 95
867 shp_missile_defense(coord dx, coord dy, natid bombown, int hardtarget)
872 double gun, eff, teff;
874 snxtitem_dist(&ni, EF_SHIP, dx, dy, 1);
876 while (nxtitem(&ni, &ship)) {
880 if (!(mchr[(int)ship.shp_type].m_flags & M_ANTIMISSILE))
883 if (relations_with(ship.shp_own, bombown) >= NEUTRAL)
886 if (ship.shp_effic < 60)
889 if (ship.shp_item[I_MILIT] < 1) /* do we have mil? */
891 if (ship.shp_item[I_GUN] < 1) /* we need at least 1 gun */
893 if (!shp_supply(&ship, I_SHELL, 2))
895 ship.shp_item[I_SHELL] -= 2;
896 putship(ship.shp_uid, &ship);
898 /* now calculate the odds */
899 gun = shp_usable_guns(&ship);
900 eff = ship.shp_effic / 100.0;
901 teff = ship.shp_tech / (ship.shp_tech + 200.0);
902 /* raise 4.5 for better interception -KHS */
903 hitchance = (int)(gun * eff * teff * 4.5) - hardtarget;
904 hitchance = LIMIT_TO(hitchance, 0, 100);
905 hit = pct_chance(hitchance);
907 mpr(bombown, "%s anti-missile system activated...%s\n",
909 hit ? "KABOOOM!! Missile destroyed\n"
910 : "SWOOSH!! anti-missile system failed!!");
911 mpr(ship.shp_own, "Ship #%i anti-missile system activated!\n",
913 mpr(ship.shp_own, "%d%% hitchance...%s\n", hitchance,
914 hit ? "KABOOOM!! Incoming missile destroyed!\n"
915 : "SWOOSH!! Missile evades anti-missile systems\n");
920 return 0; /* all attempts failed */
924 /* Fire missiles at a ship which has fired shells */
926 shp_missdef(struct shpstr *sp, natid victim)
928 struct emp_qelem list;
934 mlp = shp_insque(sp, &list);
935 sprintf(buf, "%s", prship(&mlp->unit.ship));
938 shp_missile_interdiction(&list, sp->shp_x, sp->shp_y, sp->shp_own);
939 getship(sp->shp_uid, sp);
943 "missiles launched in defense did 100%% damage to %s\n",
945 wu(0, victim, "%s sunk!\n", buf);
946 } else if (eff > 0 && sp->shp_effic < eff) {
948 "missiles launched in defense did %d%% damage to %s\n",
949 100 * (eff - sp->shp_effic) / eff, buf);
956 shp_mobcost(struct shpstr *sp)
958 return speed_factor(sp->shp_effic * 0.01 * shp_speed(sp),
963 * Set SP's tech to TLEV along with everything else that depends on it.
966 shp_set_tech(struct shpstr *sp, int tlev)
968 struct mchrstr *mcp = mchr + sp->shp_type;
970 if (CANT_HAPPEN(tlev < mcp->m_tech))