2 * Empire - A multi-player, client/server Internet based war game.
3 * Copyright (C) 1986-2015, 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 * lndsub.c: Land unit subroutines
29 * Known contributors to this file:
31 * Steve McClure, 1998-2000
32 * Markus Armbruster, 2004-2015
51 #include "prototypes.h"
55 static void lnd_mar_put_one(struct ulist *);
56 static int lnd_check_one_mines(struct ulist *, int);
57 static void lnd_stays(natid, char *, struct ulist *);
58 static int lnd_hit_mine(struct lndstr *);
59 static int has_helpful_engineer(coord, coord, natid);
62 lnd_find_capable(struct emp_qelem *list, int flags)
67 for (qp = list->q_back; qp != list; qp = qp->q_back) {
68 llp = (struct ulist *)qp;
69 if (lchr[llp->unit.land.lnd_type].l_flags & flags)
76 attack_val(int combat_mode, struct lndstr *lp)
82 if (lp->lnd_effic < LAND_MINEFF) {
83 putland(lp->lnd_uid, lp);
87 lcp = &lchr[(int)lp->lnd_type];
89 /* Spies always count as 1 during assaults. If they are the only ones
90 in the assault, they get to sneak on anyway. */
92 if (lcp->l_flags & L_SPY && combat_mode == A_ASSAULT)
95 men = lp->lnd_item[I_MILIT];
96 value = men * lnd_att(lp) * lp->lnd_effic / 100.0;
98 switch (combat_mode) {
102 if (!(lcp->l_flags & L_MARINE))
103 return assault_penalty * value;
106 if (!(lcp->l_flags & L_MARINE))
107 return assault_penalty * men;
114 defense_val(struct lndstr *lp)
120 if (lp->lnd_effic < LAND_MINEFF) {
121 putland(lp->lnd_uid, lp);
125 lcp = &lchr[(int)lp->lnd_type];
127 men = lp->lnd_item[I_MILIT];
129 if ((lp->lnd_ship >= 0 || lp->lnd_land >= 0) &&
130 !(lcp->l_flags & L_MARINE))
133 value = men * lnd_def(lp) * lp->lnd_effic / 100.0;
134 value *= ((double)land_mob_max + lp->lnd_harden) / land_mob_max;
136 /* If there are military on the unit, you get at least a 1
137 man defensive unit, except for spies */
138 if (value < 1.0 && men > 0 && !(lcp->l_flags & L_SPY))
145 lnd_reaction_range(struct lndstr *lp)
149 getsect(lp->lnd_x, lp->lnd_y, §);
150 if (sect.sct_type == SCT_HEADQ && sect.sct_effic >= 60)
151 return lchr[lp->lnd_type].l_rad + 1;
152 return lchr[lp->lnd_type].l_rad;
156 lnd_print(natid actor, struct ulist *llp, char *s)
158 if (actor == player->cnum)
159 pr("%s %s\n", prland(&llp->unit.land), s);
161 wu(0, actor, "%s %s\n", prland(&llp->unit.land), s);
165 lnd_take_casualty(int combat_mode, struct ulist *llp, int cas)
166 /* attacking or assaulting or paratrooping? */
167 /* number of casualties to take */
179 int nowhere_to_go = 0;
180 double mobcost, bmcost;
184 taken = llp->unit.land.lnd_item[I_MILIT];
185 /* Spies always die */
186 if (lchr[llp->unit.land.lnd_type].l_flags & L_SPY)
187 llp->unit.land.lnd_effic = 0;
189 eff_eq = ldround(cas * 100.0 /
190 lchr[llp->unit.land.lnd_type].l_item[I_MILIT], 1);
191 llp->unit.land.lnd_effic -= eff_eq;
192 lnd_submil(&llp->unit.land, cas);
195 if (llp->unit.land.lnd_effic < LAND_MINEFF) {
196 sprintf(buf, "dies %s %s!",
197 combat_mode ? att_mode[combat_mode] : "defending",
198 xyas(llp->unit.land.lnd_x, llp->unit.land.lnd_y,
199 llp->unit.land.lnd_own));
200 lnd_print(llp->unit.land.lnd_own, llp, buf);
202 /* Since we killed the unit, we killed all the mil on it */
205 /* Ok, now, how many did we take off? (sould be the diff) */
206 taken = taken - llp->unit.land.lnd_item[I_MILIT];
209 if (llp->unit.land.lnd_effic >= llp->unit.land.lnd_retreat)
212 /* we're being boarded */
213 if (llp->unit.land.lnd_ship >= 0 && combat_mode == A_DEFEND)
216 /* we're being boarded */
217 if (llp->unit.land.lnd_land >= 0 && combat_mode == A_DEFEND)
220 /* Have to make a retreat check */
222 ret_chance = llp->unit.land.lnd_retreat - llp->unit.land.lnd_effic;
223 if (pct_chance(ret_chance)) {
225 lnd_print(llp->unit.land.lnd_own, llp, "fails morale check!");
226 llp->unit.land.lnd_mission = 0;
227 llp->unit.land.lnd_harden = 0;
228 if (llp->unit.land.lnd_ship >= 0 || llp->unit.land.lnd_land >= 0)
230 else if (combat_mode == A_DEFEND) {
232 * defending unit.. find a place to send it
233 * strategy: look for the most-populated
234 * adjacent sector that is owned by the unit
235 * owner. Charge mob..
238 for (n = 1; n <= 6; ++n) {
239 ret_x = llp->unit.land.lnd_x + diroff[n][0];
240 ret_y = llp->unit.land.lnd_y + diroff[n][1];
241 getsect(ret_x, ret_y, §);
242 if (sect.sct_own != llp->unit.land.lnd_own)
244 if (sect.sct_type == SCT_MOUNT)
246 mobcost = lnd_mobcost(&llp->unit.land, §);
249 civs = sect.sct_item[I_CIVIL];
250 if (civs > biggest) {
260 /* retreat to bx,by */
261 llp->unit.land.lnd_x = bx;
262 llp->unit.land.lnd_y = by;
263 /* FIXME landmines */
264 mob = llp->unit.land.lnd_mobil - (int)bmcost;
267 orig = llp->unit.land.lnd_mobil;
268 llp->unit.land.lnd_mobil = (signed char)mob;
269 if (llp->unit.land.lnd_mobil > orig)
270 llp->unit.land.lnd_mobil = -127;
271 sprintf(buf, "retreats at %d%% efficiency to %s!",
272 llp->unit.land.lnd_effic,
273 xyas(bx, by, llp->unit.land.lnd_own));
274 lnd_print(llp->unit.land.lnd_own, llp, buf);
277 } else { /* attacking from a sector */
278 sprintf(buf, "leaves the battlefield at %d%% efficiency",
279 llp->unit.land.lnd_effic);
280 if ((llp->unit.land.lnd_mobil - (int)llp->mobil) < -127)
281 llp->unit.land.lnd_mobil = -127;
283 llp->unit.land.lnd_mobil -= (int)llp->mobil;
285 lnd_print(llp->unit.land.lnd_own, llp, buf);
290 /* nowhere to go.. take more casualties */
291 llp->unit.land.lnd_effic -= 10;
292 lnd_submil(&llp->unit.land,
293 lchr[llp->unit.land.lnd_type].l_item[I_MILIT] / 10);
294 if (llp->unit.land.lnd_effic < LAND_MINEFF) {
295 lnd_print(llp->unit.land.lnd_own, llp,
296 "has nowhere to retreat, and dies!");
299 lnd_print(llp->unit.land.lnd_own, llp,
300 "has nowhere to retreat and takes extra losses!");
307 lnd_takemob(struct emp_qelem *list, double loss)
309 struct emp_qelem *qp, *next;
312 int mcost = ldround(combat_mob * loss, 1);
314 for (qp = list->q_forw; qp != list; qp = next) {
316 llp = (struct ulist *)qp;
319 use_supply(&llp->unit.land);
321 new = llp->unit.land.lnd_mobil - mcost;
324 llp->unit.land.lnd_mobil = (signed char)new;
329 lnd_submil(struct lndstr *lp, int num)
331 int new = lp->lnd_item[I_MILIT] - num;
332 lp->lnd_item[I_MILIT] = new < 0 ? 0 : new;
336 lnd_spyval(struct lndstr *lp)
338 if (lchr[(int)lp->lnd_type].l_flags & L_RECON)
339 return lchr[lp->lnd_type].l_spy * (lp->lnd_effic / 100.0) + 2;
341 return lchr[lp->lnd_type].l_spy * (lp->lnd_effic / 100.0);
345 intelligence_report(int destination, struct lndstr *lp, int spy,
348 int vis = lnd_vis(lp);
349 char buf1[80], buf2[80], buf3[80];
351 if (destination == 0)
354 if (lp->lnd_own == 0)
357 memset(buf1, 0, sizeof(buf1));
358 memset(buf2, 0, sizeof(buf2));
359 memset(buf3, 0, sizeof(buf3));
360 if (chance((spy + vis) / 10.0)) {
361 if (destination == player->cnum)
362 pr("%s %s", mess, prland(lp));
364 sprintf(buf1, "%s %s", mess, prland(lp));
366 if (chance((spy + vis) / 20.0)) {
367 if (destination == player->cnum)
368 pr(" (eff %d, mil %d",
369 roundintby(lp->lnd_effic, 5),
370 roundintby(lp->lnd_item[I_MILIT], 10));
372 sprintf(buf2, " (eff %d, mil %d",
373 roundintby(lp->lnd_effic, 5),
374 roundintby(lp->lnd_item[I_MILIT], 10));
376 if (chance((spy + vis) / 20.0)) {
378 t = lp->lnd_tech - 20 + roll(40);
380 if (destination == player->cnum)
381 pr(", tech %d)\n", t);
383 sprintf(buf3, ", tech %d)\n", t);
385 if (destination == player->cnum)
388 sprintf(buf3, ")\n");
391 if (destination == player->cnum)
398 if (destination != player->cnum) {
399 wu(0, destination, "%s%s%s", buf1, buf2, buf3);
404 lnd_may_mar(struct lndstr *lp, struct lndstr *ldr, char *suffix)
408 if (!lp->lnd_own || !getsect(lp->lnd_x, lp->lnd_y, §)) {
413 if (lp->lnd_ship >= 0) {
414 mpr(lp->lnd_own, "%s is on a ship%s\n", prland(lp), suffix);
417 if (lp->lnd_land >= 0) {
418 mpr(lp->lnd_own, "%s is on a unit%s\n", prland(lp), suffix);
422 if (!(lchr[lp->lnd_type].l_flags & L_SPY) &&
423 !(lchr[lp->lnd_type].l_flags & L_TRAIN) &&
424 lp->lnd_item[I_MILIT] == 0) {
425 mpr(lp->lnd_own, "%s has no mil on it to guide it%s\n",
430 switch (lnd_check_mar(lp, §)) {
433 case LND_STUCK_NO_RAIL:
434 mpr(lp->lnd_own, "%s is stuck off the rail system%s\n",
440 case LND_STUCK_IMPASSABLE:
441 mpr(lp->lnd_own, "%s is stuck%s\n", prland(lp), suffix);
445 if (relations_with(sect.sct_own, lp->lnd_own) != ALLIED &&
446 !(lchr[lp->lnd_type].l_flags & L_SPY) &&
448 mpr(lp->lnd_own, "%s has been kidnapped by %s%s\n",
449 prland(lp), cname(sect.sct_own), suffix);
453 if (ldr && (lp->lnd_x != ldr->lnd_x || lp->lnd_y != ldr->lnd_y)) {
454 mpr(lp->lnd_own, "%s is not with the leader%s\n",
462 lnd_sel(struct nstr_item *ni, struct emp_qelem *list)
466 int mobtype = MOB_MOVE; /* indeterminate */
469 while (nxtitem(ni, &land)) {
471 * It would be nice to let deities march foreign land units,
472 * but much of the code assumes that only the land unit's
473 * owner can march it.
475 if (!land.lnd_own || land.lnd_own != player->cnum)
478 if (ontradingblock(EF_LAND, &land)) {
479 pr("unit #%d inelligible - it's for sale.\n",
485 * The marching code gets confused when trains and non-trains
486 * march together. Disallow for now.
488 this_mot = lnd_mobtype(&land);
489 if (this_mot != mobtype) {
490 if (mobtype == MOB_MOVE)
492 else if (mobtype == MOB_MARCH) {
493 pr("%s is a train and can't march with the leader.\n",
497 pr("%s can't rail-march with the leading train.\n",
503 land.lnd_mission = 0;
506 memset(land.lnd_rpath, 0, sizeof(land.lnd_rpath));
507 putland(land.lnd_uid, &land);
508 lnd_insque(&land, list);
514 * Return the new list link.
517 lnd_insque(struct lndstr *lp, struct emp_qelem *list)
519 struct ulist *mlp = malloc(sizeof(struct ulist));
521 mlp->unit.land = *lp;
522 mlp->mobil = lp->lnd_mobil;
523 emp_insque(&mlp->queue, list);
527 /* This function assumes that the list was created by lnd_sel */
529 lnd_mar(struct emp_qelem *list, double *minmobp, double *maxmobp,
532 struct emp_qelem *qp;
533 struct emp_qelem *next;
535 struct lndstr *lp, *ldr = NULL;
540 for (qp = list->q_back; qp != list; qp = next) {
542 llp = (struct ulist *)qp;
543 lp = &llp->unit.land;
544 getland(lp->lnd_uid, lp);
546 if (lp->lnd_own != actor) {
547 mpr(actor, "%s was disbanded at %s\n",
548 prland(lp), xyas(lp->lnd_x, lp->lnd_y, actor));
549 emp_remque(&llp->queue);
554 snprintf(and_stays, sizeof(and_stays), " & stays in %s",
555 xyas(lp->lnd_x, lp->lnd_y, actor));
556 if (!lnd_may_mar(lp, ldr, and_stays)) {
557 lnd_mar_put_one(llp);
563 if (lp->lnd_mobil + 1 < (int)llp->mobil) {
564 llp->mobil = lp->lnd_mobil;
566 if (llp->mobil < *minmobp)
567 *minmobp = llp->mobil;
568 if (llp->mobil > *maxmobp)
569 *maxmobp = llp->mobil;
574 lnd_mar_put_one(struct ulist *llp)
576 if (llp->mobil < -127)
578 llp->unit.land.lnd_mobil = llp->mobil;
583 lnd_mar_put(struct emp_qelem *list, natid actor)
585 struct emp_qelem *qp, *next;
589 for (qp = list->q_back; qp != list; qp = next) {
591 llp = (struct ulist *)qp;
592 lp = &llp->unit.land;
593 mpr(actor, "%s stopped at %s\n",
594 prland(lp), xyas(lp->lnd_x, lp->lnd_y, actor));
595 lnd_mar_put_one(llp);
600 lnd_put(struct emp_qelem *list)
602 struct emp_qelem *qp, *next;
604 for (qp = list->q_back; qp != list; qp = next) {
606 lnd_put_one((struct ulist *)qp);
611 lnd_put_one(struct ulist *llp)
613 putland(llp->unit.land.lnd_uid, &llp->unit.land);
614 emp_remque(&llp->queue);
619 * Sweep landmines with engineers in LAND_LIST for ACTOR.
620 * All land units in LAND_LIST must be in the same sector.
621 * If EXPLICIT is non-zero, this is for an explicit sweep command from
622 * a player. Else it's an automatic "on the move" sweep.
623 * If TAKEMOB is non-zero, require and charge mobility.
624 * Return non-zero when the land units should stop.
627 lnd_sweep(struct emp_qelem *land_list, int explicit, int takemob,
630 struct emp_qelem *qp;
631 struct emp_qelem *next;
634 int mines, m, max, sshells, lshells;
635 int stopping = 0, first = 1;
637 llp = lnd_find_capable(land_list, L_ENGINEER);
640 mpr(actor, "No engineers!\n");
644 getsect(llp->unit.land.lnd_x, llp->unit.land.lnd_y, §);
646 && relations_with(sect.sct_oldown, actor) == ALLIED)
648 if (SCT_MINES_ARE_SEAMINES(§)) {
650 mpr(actor, "%s is a %s. No landmines there!\n",
651 xyas(sect.sct_x, sect.sct_y, actor),
652 dchr[sect.sct_type].d_name);
656 for (qp = land_list->q_back; qp != land_list; qp = next) {
658 llp = (struct ulist *)qp;
659 if (!(lchr[llp->unit.land.lnd_type].l_flags & L_ENGINEER))
662 if (llp->mobil <= 0.0) {
664 mpr(actor, "%s is out of mobility!\n",
665 prland(&llp->unit.land));
668 llp->mobil -= lnd_pathcost(&llp->unit.land, 0.2);
669 llp->unit.land.lnd_mobil = (int)llp->mobil;
670 llp->unit.land.lnd_harden = 0;
672 putland(llp->unit.land.lnd_uid, &llp->unit.land);
673 getsect(llp->unit.land.lnd_x, llp->unit.land.lnd_y, §);
674 if (!(mines = sect.sct_mines))
676 max = lchr[llp->unit.land.lnd_type].l_item[I_SHELL];
677 lshells = llp->unit.land.lnd_item[I_SHELL];
678 sshells = sect.sct_item[I_SHELL];
679 for (m = 0; mines > 0 && m < max * 2; m++) {
680 if (chance(0.5 * lchr[llp->unit.land.lnd_type].l_att)) {
682 mpr(actor, "Approaching minefield at %s...\n",
683 xyas(sect.sct_x, sect.sct_y, actor));
686 mpr(actor, "Sweep...\n");
690 else if (sshells < ITEM_MAX)
694 sect.sct_mines = mines;
695 llp->unit.land.lnd_item[I_SHELL] = lshells;
696 sect.sct_item[I_SHELL] = sshells;
697 putland(llp->unit.land.lnd_uid, &llp->unit.land);
699 if (lnd_check_one_mines(llp, 1)) {
709 lnd_check_one_mines(struct ulist *llp, int with_eng)
713 getsect(llp->unit.land.lnd_x, llp->unit.land.lnd_y, §);
714 if (SCT_LANDMINES(§) == 0)
716 if (relations_with(sect.sct_oldown, llp->unit.land.lnd_own) == ALLIED)
718 if (chance(DMINE_LHITCHANCE(sect.sct_mines) / (1 + 2 * with_eng))) {
719 lnd_hit_mine(&llp->unit.land);
722 putland(llp->unit.land.lnd_uid, &llp->unit.land);
723 if (!llp->unit.land.lnd_own)
730 lnd_check_mines(struct emp_qelem *land_list)
732 struct emp_qelem *qp;
733 struct emp_qelem *next;
736 int with_eng = !!lnd_find_capable(land_list, L_ENGINEER);
738 for (qp = land_list->q_back; qp != land_list; qp = next) {
740 llp = (struct ulist *)qp;
741 if (lnd_check_one_mines(llp, with_eng)) {
751 lnd_stays(natid actor, char *str, struct ulist *llp)
753 mpr(actor, "%s %s & stays in %s\n",
754 prland(&llp->unit.land), str,
755 xyas(llp->unit.land.lnd_x, llp->unit.land.lnd_y, actor));
756 lnd_mar_put_one(llp);
759 /* Return whether and why SP would be stuck in SECTP. */
761 lnd_check_mar(struct lndstr *lp, struct sctstr *sectp)
763 if (dchr[sectp->sct_type].d_mob0 < 0)
764 return LND_STUCK_IMPASSABLE;
765 if (lnd_mobtype(lp) == MOB_RAIL && !SCT_HAS_RAIL(sectp))
766 return LND_STUCK_NO_RAIL;
767 return LND_STUCK_NOT;
771 lnd_damage(struct emp_qelem *list, int totdam)
773 struct emp_qelem *qp;
774 struct emp_qelem *next;
779 if (!totdam || !(count = emp_quelen(list)))
781 dam = ldround((double)totdam / count, 1);
782 for (qp = list->q_back; qp != list; qp = next) {
784 llp = (struct ulist *)qp;
785 /* land unit might have changed (launched SAMs, collateral dmg) */
786 getland(llp->unit.land.lnd_uid, &llp->unit.land);
787 landdamage(&llp->unit.land, dam);
788 putland(llp->unit.land.lnd_uid, &llp->unit.land);
789 if (!llp->unit.land.lnd_own) {
798 lnd_easiest_target(struct emp_qelem *list)
800 struct emp_qelem *qp;
801 struct emp_qelem *next;
804 int easiest = 9876; /* things start great for victim */
807 for (qp = list->q_back; qp != list; qp = next) {
809 llp = (struct ulist *)qp;
810 hard = lnd_hardtarget(&llp->unit.land);
812 easiest = hard; /* things get worse for victim */
815 return easiest - count;
819 lnd_missile_interdiction(struct emp_qelem *list, coord newx, coord newy,
822 int mindam = emp_quelen(list) * 20;
823 int hardtarget = lnd_easiest_target(list);
824 int dam, newdam, sublaunch;
827 struct emp_qelem msl_list, *qp, *newqp;
829 msl_sel(&msl_list, newx, newy, victim, P_T, P_MAR, MI_INTERDICT);
832 for (qp = msl_list.q_back; qp != &msl_list; qp = newqp) {
834 plp = (struct plist *)qp;
836 if (dam < mindam && mission_pln_equip(plp, NULL, 'p') >= 0) {
837 if (msl_launch(&plp->plane, EF_LAND, "troops",
838 newx, newy, victim, &sublaunch) < 0)
841 if (msl_hit(&plp->plane, hardtarget, EF_LAND,
842 N_LND_MISS, N_LND_SMISS, sublaunch, victim)) {
843 newdam = pln_damage(&plp->plane, 'p', 1);
846 newdam = pln_damage(&plp->plane, 'p', 0);
847 collateral_damage(newx, newy, newdam);
850 plp->plane.pln_effic = 0;
851 putplane(plp->plane.pln_uid, &plp->plane);
858 mpr(victim, "missile interdiction mission does %d damage!\n", dam);
859 collateral_damage(newx, newy, dam);
860 lnd_damage(list, dam);
866 /* Steve M. - commented out for now until abuse is decided upon */
867 /* risner: allow forts to interdict land units. */
869 lnd_fort_interdiction(struct emp_qelem *list,
870 coord newx, coord newy, natid victim)
879 snxtsct_dist(&ns, newx, newy, fort_max_interdiction_range);
880 while (nxtsct(&ns, &fsect)) {
881 if (fsect.sct_own == 0)
883 if (relations_with(fsect.sct_own, victim) >= NEUTRAL)
885 range = roundrange(fortrange(&fsect));
886 trange = mapdist(newx, newy, fsect.sct_x, fsect.sct_y);
889 dam = fort_fire(&fsect);
895 mpr(victim, "Incoming fire does %d damage!\n", dam);
897 "%s fires at %s land units in %s for %d!\n",
898 xyas(fsect.sct_x, fsect.sct_y,
900 cname(victim), xyas(newx, newy, fsect.sct_own), dam);
901 nreport(fsect.sct_own, N_SCT_SHELL, victim, 1);
904 lnd_damage(list, totdam);
910 lnd_mission_interdiction(struct emp_qelem *list, coord x, coord y,
915 dam = unit_interdict(x, y, victim, "land units",
916 lnd_easiest_target(list),
919 lnd_damage(list, dam);
924 lnd_interdict(struct emp_qelem *list, coord newx, coord newy, natid victim)
929 if (!opt_NO_FORT_FIRE)
930 /* Steve M. - commented out for now until abuse is decided upon */
931 stopping |= lnd_fort_interdiction(list, newx, newy, victim);
934 stopping |= lnd_mission_interdiction(list, newx, newy, victim);
935 stopping |= lnd_missile_interdiction(list, newx, newy, victim);
939 /* high value of hardtarget is harder to hit */
941 lnd_hardtarget(struct lndstr *lp)
945 getsect(lp->lnd_x, lp->lnd_y, §);
946 return (int)((lp->lnd_effic / 100.0) *
947 (10 + dchr[sect.sct_type].d_dstr * 2 + lnd_spd(lp) / 2.0
952 lnd_hit_mine(struct lndstr *lp)
956 mpr(lp->lnd_own, "Blammo! Landmines detected in %s!\n",
957 xyas(lp->lnd_x, lp->lnd_y, lp->lnd_own));
959 nreport(lp->lnd_own, N_LHIT_MINE, 0, 1);
962 if (lchr[lp->lnd_type].l_flags & L_ENGINEER)
970 lnd_pathcost(struct lndstr *lp, double pathcost)
974 effspd = lnd_spd(lp);
975 if (lchr[(int)lp->lnd_type].l_flags & L_SUPPLY)
976 effspd *= lp->lnd_effic * 0.01;
979 * The return value must be PATHCOST times a factor that depends
980 * only on the land unit. Anything else breaks path finding. In
981 * particular, you can't add or enforce a minimum cost here. Do
982 * it in sector_mcost().
984 return pathcost * 5.0 * speed_factor(effspd, lp->lnd_tech);
988 lnd_mobtype(struct lndstr *lp)
990 return (lchr[(int)lp->lnd_type].l_flags & L_TRAIN)
991 ? MOB_RAIL : MOB_MARCH;
995 lnd_mobcost(struct lndstr *lp, struct sctstr *sp)
997 return lnd_pathcost(lp, sector_mcost(sp, lnd_mobtype(lp)));
1001 * Ask user to confirm sector abandonment, if any.
1002 * All land units in LIST must be in the same sector.
1003 * If removing the land units in LIST would abandon their sector, ask
1004 * the user to confirm.
1005 * Return zero when abandonment was declined, else non-zero.
1007 int lnd_abandon_askyn(struct emp_qelem *list)
1011 struct emp_qelem *qp;
1015 llp = (struct ulist *)list->q_back;
1016 getsect(llp->unit.land.lnd_x, llp->unit.land.lnd_y, §);
1017 if (!abandon_askyn(§, I_CIVIL, 0, llp))
1019 if (!check_sect_ok(§))
1021 for (qp = list->q_back; qp != list; qp = qp->q_back) {
1022 if (!check_land_ok(&((struct ulist *)qp)->unit.land))
1029 lnd_mar_one_sector(struct emp_qelem *list, int dir, natid actor)
1031 struct sctstr sect, osect;
1032 struct emp_qelem *qp;
1033 struct emp_qelem *next;
1046 if (CANT_HAPPEN(QEMPTY(list)))
1049 if (dir <= DIR_STOP || dir > DIR_LAST) {
1050 CANT_HAPPEN(dir != DIR_STOP);
1051 lnd_mar_put(list, actor);
1054 dx = diroff[dir][0];
1055 dy = diroff[dir][1];
1057 llp = (struct ulist *)list->q_back;
1058 getsect(llp->unit.land.lnd_x, llp->unit.land.lnd_y, &osect);
1059 oldown = osect.sct_own;
1060 newx = xnorm(llp->unit.land.lnd_x + dx);
1061 newy = ynorm(llp->unit.land.lnd_y + dy);
1062 getsect(newx, newy, §);
1063 rel = sect.sct_own ? relations_with(sect.sct_own, actor) : ALLIED;
1066 for (qp = list->q_back; qp != list; qp = next) {
1068 llp = (struct ulist *)qp;
1069 switch (lnd_check_mar(&llp->unit.land, §)) {
1072 || (lchr[llp->unit.land.lnd_type].l_flags & L_SPY))
1075 case LND_STUCK_NO_RAIL:
1077 mpr(actor, "no rail system in %s\n",
1078 xyas(newx, newy, actor));
1080 mpr(actor, "can't go to %s\n", xyas(newx, newy, actor));
1085 case LND_STUCK_IMPASSABLE:
1086 mpr(actor, "can't go to %s\n", xyas(newx, newy, actor));
1091 mpr(actor, "can't go to %s\n", xyas(newx, newy, actor));
1095 for (qp = list->q_back; qp != list; qp = next) {
1097 llp = (struct ulist *)qp;
1099 && !(lchr[llp->unit.land.lnd_type].l_flags & L_SPY)) {
1100 sprintf(dp, "can't go to %s", xyas(newx, newy, actor));
1101 lnd_stays(actor, dp, llp);
1104 if (llp->mobil <= 0.0) {
1105 lnd_stays(actor, "is out of mobility", llp);
1108 llp->unit.land.lnd_x = newx;
1109 llp->unit.land.lnd_y = newy;
1110 llp->mobil -= lnd_mobcost(&llp->unit.land, §);
1111 llp->unit.land.lnd_mobil = (int)llp->mobil;
1112 llp->unit.land.lnd_harden = 0;
1113 putland(llp->unit.land.lnd_uid, &llp->unit.land);
1115 getsect(osect.sct_x, osect.sct_y, &osect);
1116 if (osect.sct_own != oldown && oldown == actor) {
1117 /* It was your sector, now it's not. Simple :) */
1118 mpr(actor, "You no longer own %s\n",
1119 xyas(osect.sct_x, osect.sct_y, actor));
1121 if (rel != ALLIED) {
1123 /* Always a 10% chance of getting caught. */
1124 if (chance(LND_SPY_DETECT_CHANCE(llp->unit.land.lnd_effic))) {
1125 if (rel == NEUTRAL || rel == FRIENDLY) {
1127 "%s unit spotted in %s\n", cname(actor),
1128 xyas(sect.sct_x, sect.sct_y, sect.sct_own));
1129 setrel(sect.sct_own, llp->unit.land.lnd_own, HOSTILE);
1130 } else if (rel <= HOSTILE) {
1132 "%s spy shot in %s\n", cname(actor),
1133 xyas(sect.sct_x, sect.sct_y, sect.sct_own));
1134 mpr(actor, "%s was shot and killed.\n",
1135 prland(&llp->unit.land));
1136 llp->unit.land.lnd_effic = 0;
1137 putland(llp->unit.land.lnd_uid, &llp->unit.land);
1145 stopping |= lnd_sweep(list, 0, 1, actor);
1148 stopping |= lnd_check_mines(list);
1153 for (qp = list->q_back; qp != list; qp = next) {
1155 llp = (struct ulist *)qp;
1156 if (!(lchr[(int)llp->unit.land.lnd_type].l_flags & L_SPY))
1160 stopping |= lnd_interdict(list, newx, newy, actor);
1166 * Fire land unit support against VICTIM for ATTACKER, at X,Y.
1167 * If DEFENDING, this is defensive support, else offensive support.
1168 * Return total damage.
1171 lnd_support(natid victim, natid attacker, coord x, coord y, int defending)
1173 struct nstr_item ni;
1180 snxtitem_all(&ni, EF_LAND);
1181 while (nxtitem(&ni, &land)) {
1182 if ((land.lnd_x == x) && (land.lnd_y == y))
1184 if (!feels_like_helping(land.lnd_own, attacker, victim))
1187 /* are we in range? */
1188 dist = mapdist(land.lnd_x, land.lnd_y, x, y);
1190 range = roundrange(lnd_fire_range(&land));
1194 dam2 = lnd_fire(&land);
1195 putland(land.lnd_uid, &land);
1200 nreport(land.lnd_own, N_FIRE_BACK, victim, 1);
1202 nreport(land.lnd_own, N_FIRE_L_ATTACK, victim, 1);
1203 if (pct_chance(lnd_acc(&land) - 1))
1206 if (land.lnd_own != attacker)
1208 "%s supported %s at %s\n",
1209 prland(&land), cname(attacker), xyas(x, y, land.lnd_own));
1215 lnd_can_attack(struct lndstr *lp)
1217 struct lchrstr *lcp = &lchr[(int)lp->lnd_type];
1219 if (lcp->l_flags & L_SUPPLY)
1226 * Increase fortification value of LP.
1227 * Fortification costs mobility. Use up to MOB mobility.
1228 * Return actual fortification increase.
1231 lnd_fortify(struct lndstr *lp, int mob)
1234 double mob_used, mult;
1236 if (lp->lnd_ship >= 0 || lp->lnd_land >= 0)
1239 mob_used = MIN(lp->lnd_mobil, mob);
1243 mult = has_helpful_engineer(lp->lnd_x, lp->lnd_y, lp->lnd_own)
1246 hard_amt = (int)(mob_used * mult);
1247 if (lp->lnd_harden + hard_amt > land_mob_max) {
1248 hard_amt = land_mob_max - lp->lnd_harden;
1249 mob_used = ceil(hard_amt / mult);
1252 lp->lnd_mobil -= (int)mob_used;
1253 lp->lnd_harden += hard_amt;
1254 lp->lnd_harden = MIN(lp->lnd_harden, land_mob_max);
1260 * Is there a engineer unit at X,Y that can help nation CN?
1263 has_helpful_engineer(coord x, coord y, natid cn)
1265 struct nstr_item ni;
1268 snxtitem_xy(&ni, EF_LAND, x, y);
1269 while (nxtitem(&ni, &land)) {
1270 if (relations_with(land.lnd_own, cn) != ALLIED)
1272 if (lchr[(int)land.lnd_type].l_flags & L_ENGINEER)
1280 * Set LP's tech to TLEV along with everything else that depends on it.
1283 lnd_set_tech(struct lndstr *lp, int tlev)
1285 struct lchrstr *lcp = lchr + lp->lnd_type;
1287 if (CANT_HAPPEN(tlev < lcp->l_tech))
1290 lp->lnd_tech = tlev;