git.pond.sub.org Git - empserver/blob - src/lib/commands/torp.c

   1 /*
   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
   5  *
   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.
  10  *
  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.
  15  *
  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/>.
  18  *
  19  *  ---
  20  *
  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.
  24  *
  25  *  ---
  26  *
  27  *  torp.c: Fire torpedoes at enemy ships
  28  *
  29  *  Known contributors to this file:
  30  *     Dave Pare
  31  *     Thomas Ruschak, 1992
  32  *     Ken Stevens, 1995
  33  *     Steve McClure, 2000
  34  *     Markus Armbruster, 2004-2015
  35  */
  36
  37 #include <config.h>
  38
  39 #include "chance.h"
  40 #include "commands.h"
  41 #include "news.h"
  42 #include "retreat.h"
  43 #include "ship.h"
  44
  45 static void anti_torp(int f, int ntorping, int vshipown);
  46 static void fire_dchrg(struct shpstr *, struct shpstr *, int);
  47 static int fire_torp(struct shpstr *, struct shpstr *, int);
  48
  49 int
  50 torp(void)
  51 {
  52     natid vshipown;
  53     int range;
  54     int dam;
  55     int subno;
  56     int victno;
  57     int erange;
  58     double hitchance;
  59     struct shpstr vship;
  60     struct shpstr sub;
  61     char *ptr;
  62     struct nstr_item nbst;
  63     char buf[1024];
  64     int ntorping = 0;
  65     char prompt[128];
  66
  67     if (!snxtitem(&nbst, EF_SHIP, player->argp[1], "From ship(s)? "))
  68         return RET_SYN;
  69     while (nxtitem(&nbst, &sub)) {
  70         if (sub.shp_own != player->cnum)
  71             continue;
  72         if ((mchr[(int)sub.shp_type].m_flags & M_TORP) == 0)
  73             continue;
  74         if (sub.shp_item[I_GUN] == 0
  75             || sub.shp_item[I_SHELL] < SHP_TORP_SHELLS)
  76             continue;
  77         if (sub.shp_item[I_MILIT] < 1)
  78             continue;
  79         if (sub.shp_effic < 60)
  80             continue;
  81         if (sub.shp_mobil <= 0)
  82             continue;
  83         ntorping++;
  84     }
  85     pr("%d ships are eligible to torpedo\n", ntorping);
  86     snxtitem_rewind(&nbst);
  87     while (nxtitem(&nbst, &sub)) {
  88         if (!sub.shp_own)
  89             continue;
  90         if (sub.shp_own != player->cnum) {
  91             continue;
  92         }
  93         if ((mchr[(int)sub.shp_type].m_flags & M_TORP) == 0) {
  94             pr("Ship # %d: A %s can't fire torpedoes!\n",
  95                sub.shp_uid, mchr[(int)sub.shp_type].m_name);
  96             continue;
  97         }
  98         if (sub.shp_item[I_GUN] == 0
  99             || sub.shp_item[I_SHELL] < SHP_TORP_SHELLS) {
 100             pr("Ship #%d has insufficient armament\n", sub.shp_uid);
 101             continue;
 102         }
 103         if (sub.shp_item[I_MILIT] < 1) {
 104             pr("Ship #%d has insufficient crew\n", sub.shp_uid);
 105             continue;
 106         }
 107         if (sub.shp_effic < 60) {
 108             pr("Ship #%d torpedo tubes inoperative.\n", sub.shp_uid);
 109             continue;
 110         }
 111         if (sub.shp_mobil <= 0) {
 112             pr("Ship #%d has insufficient mobility\n", sub.shp_uid);
 113             continue;
 114         }
 115         subno = sub.shp_uid;
 116         sprintf(prompt, "Ship %d, target? ", sub.shp_uid);
 117         if (!(ptr = getstarg(player->argp[2], prompt, buf)))
 118             return RET_SYN;
 119         if (!check_ship_ok(&sub))
 120             return RET_FAIL;
 121         if ((victno = atoi(ptr)) < 0)
 122             return RET_SYN;
 123         if (!getship(victno, &vship))
 124             return RET_FAIL;
 125         if (!vship.shp_own)
 126             return RET_FAIL;
 127         vshipown = vship.shp_own;
 128         if (victno == subno) {
 129             pr("Shooting yourself, eh?  How strange...\n");
 130             continue;
 131         }
 132         if (mchr[(int)vship.shp_type].m_flags & M_SUB) {
 133             if (!(mchr[(int)sub.shp_type].m_flags & M_SUBT)) {
 134                 pr("You can't torpedo a submarine!\n");
 135                 continue;
 136             }
 137         }
 138         dam = shp_torp(&sub, 1);
 139         sub.shp_mission = 0;
 140         putship(sub.shp_uid, &sub);
 141         if (CANT_HAPPEN(dam < 0)) {
 142             pr("Ship #%d has insufficient armament\n", sub.shp_uid);
 143             continue;
 144         }
 145
 146         if ((mchr[(int)sub.shp_type].m_flags & M_SUB) == 0)
 147             anti_torp(sub.shp_uid, ntorping, vshipown);
 148         getship(sub.shp_uid, &sub);
 149         if (sub.shp_own == 0)
 150             continue;
 151
 152         erange = roundrange(torprange(&sub));
 153         pr("Effective torpedo range is %d.0\n", erange);
 154         pr("Whooosh... ");
 155         getship(victno, &vship);
 156         vshipown = vship.shp_own;
 157         range = mapdist(sub.shp_x, sub.shp_y, vship.shp_x, vship.shp_y);
 158         hitchance = shp_torp_hitchance(&sub, range);
 159         if (range <= erange) {
 160             pr("Hitchance = %d%%\n", (int)(hitchance * 100));
 161         }
 162         /* Now, can the torpedo even get there? */
 163         if (!line_of_sight(NULL, sub.shp_x, sub.shp_y,
 164                            vship.shp_x, vship.shp_y)) {
 165             pr("BOOM!... Torpedo slams into land before reaching target.\n");
 166             /* We only tell the victim if we were within range. */
 167             if (range <= erange) {
 168                 if (vshipown != 0)
 169                     wu(0, vshipown, "Torpedo sighted @ %s by %s\n",
 170                        xyas(sub.shp_x, sub.shp_y, vshipown),
 171                        prship(&vship));
 172             }
 173         } else if (range > erange) {
 174             pr("Out of range\n");
 175         } else if (chance(hitchance)) {
 176             pr("BOOM!...\n");
 177             if (vshipown != 0)
 178                 wu(0, vshipown, "%s in %s torpedoed %s for %d damage.\n",
 179                    prsub(&sub), xyas(sub.shp_x, sub.shp_y, vshipown),
 180                    prship(&vship), dam);
 181             pr("Torpedo hit %s for %d damage.\n", prsub(&vship), dam);
 182             if (!(mchr[vship.shp_type].m_flags & M_SUB)) {
 183                 if (mchr[sub.shp_type].m_flags & M_SUB)
 184                     nreport(vshipown, N_TORP_SHIP, 0, 1);
 185                 else
 186                     nreport(vshipown, N_SHIP_TORP, player->cnum, 1);
 187             }
 188             shipdamage(&vship, dam);
 189             if (vship.shp_effic < SHIP_MINEFF)
 190                 pr("%s sunk!\n", prsub(&vship));
 191             if (vship.shp_rflags & RET_TORPED)
 192                 retreat_ship(&vship, 't');
 193             putship(vship.shp_uid, &vship);
 194         } else {
 195             pr("Missed\n");
 196             if (vshipown != 0)
 197                 wu(0, vshipown, "Torpedo sighted @ %s by %s\n",
 198                    xyas(sub.shp_x, sub.shp_y, vshipown), prship(&vship));
 199         }
 200
 201         if (mchr[(int)sub.shp_type].m_flags & M_SUB)
 202             anti_torp(sub.shp_uid, ntorping, vshipown);
 203     }
 204     return RET_OK;
 205 }
 206
 207 static void
 208 anti_torp(int f, int ntorping, int vshipown)
 209 {
 210     struct shpstr sub;
 211     struct shpstr dd;
 212     int x;
 213
 214     getship(f, &sub);
 215
 216     if (sub.shp_own == vshipown)
 217         return;
 218
 219     if ((mchr[(int)sub.shp_type].m_flags & M_SUB) == 0)
 220         pr("Starting our attack run...\n");
 221
 222     x = 0;
 223     while (getship(x++, &dd) && sub.shp_effic >= SHIP_MINEFF) {
 224         if (dd.shp_own == 0)
 225             continue;
 226         if (dd.shp_own != vshipown)
 227             continue;
 228
 229         if (!fire_torp(&dd, &sub, ntorping))
 230             fire_dchrg(&dd, &sub, ntorping);
 231     }
 232 }
 233
 234 static void
 235 fire_dchrg(struct shpstr *sp, struct shpstr *targ, int ntargets)
 236 {
 237     int range, erange, dam;
 238
 239     erange = roundrange(shp_fire_range(sp));
 240     range = mapdist(sp->shp_x, sp->shp_y, targ->shp_x, targ->shp_y);
 241     if (range > erange)
 242         return;
 243
 244     if ((mchr[(int)targ->shp_type].m_flags & M_SUB) == 0) {
 245         /* Return fire to a torpedo boat */
 246         if (mchr[sp->shp_type].m_flags & M_SUB)
 247             return;             /* sub deck gun can't return fire */
 248         dam = shp_fire(sp);
 249         putship(sp->shp_uid, sp);
 250         if (dam < 0)
 251             return;
 252         if (ntargets > 2)
 253             dam /= ntargets / 2;
 254
 255         pr_beep();
 256         pr("Kaboom!!! Incoming shells!\n");
 257         if (sp->shp_own != 0)
 258             wu(0, sp->shp_own,
 259                "%s fired at %s\n", prship(sp), prship(targ));
 260         pr_beep();
 261         pr("BLAM! %d damage!\n", dam);
 262     } else {
 263         /* Return fire to a submarine */
 264         dam = shp_dchrg(sp);
 265         putship(sp->shp_uid, sp);
 266         if (dam < 0)
 267             return;
 268         if (ntargets > 2)
 269             dam /= ntargets / 2;
 270
 271         pr("\nCAPTAIN!  !!Depth charges!!...\n");
 272         if (sp->shp_own != 0)
 273             wu(0, sp->shp_own,
 274                "%s depth charged %s\n", prship(sp), prsub(targ));
 275         pr("click...WHAM!  %d damage!\n", dam);
 276     }
 277     shipdamage(targ, dam);
 278     putship(targ->shp_uid, targ);
 279 }
 280
 281 static int
 282 fire_torp(struct shpstr *sp, struct shpstr *targ, int ntargets)
 283 {
 284     int range, erange, dam;
 285
 286     if ((mchr[targ->shp_type].m_flags & M_SUB)
 287         && (mchr[sp->shp_type].m_flags & M_SUBT) == 0)
 288         return 0;               /* need sub-torp to torpedo a sub */
 289
 290     erange = roundrange(torprange(sp));
 291     range = mapdist(sp->shp_x, sp->shp_y, targ->shp_x, targ->shp_y);
 292     if (range > erange)
 293         return 0;
 294
 295     if (!line_of_sight(NULL, sp->shp_x, sp->shp_y,
 296                        targ->shp_x, targ->shp_y))
 297         return 0;
 298     dam = shp_torp(sp, 1);
 299     putship(sp->shp_uid, sp);
 300     if (dam < 0)
 301         return 0;
 302
 303     pr("Captain! Torpedoes sighted!\n");
 304
 305     if (chance(shp_torp_hitchance(sp, range))) {
 306         pr("BOOM!...\n");
 307         if (!(mchr[targ->shp_type].m_flags & M_SUB)) {
 308             if (mchr[sp->shp_type].m_flags & M_SUB)
 309                 nreport(targ->shp_own, N_TORP_SHIP, 0, 1);
 310             else
 311                 nreport(targ->shp_own, N_SHIP_TORP, sp->shp_own, 1);
 312         }
 313         if (sp->shp_own != 0)
 314             wu(0, sp->shp_own, "%s @ %s torpedoed %s\n",
 315                prship(sp),
 316                xyas(sp->shp_x, sp->shp_y, sp->shp_own), prsub(targ));
 317         if (ntargets > 2)
 318             dam /= ntargets / 2;
 319
 320         shipdamage(targ, dam);
 321         putship(targ->shp_uid, targ);
 322
 323     } else {
 324         pr("Missed!\n");
 325         if (sp->shp_own != 0)
 326             wu(0, sp->shp_own,
 327                "%s missed %s with a torpedo at %s\n",
 328                prship(sp), prsub(targ),
 329                xyas(sp->shp_x, sp->shp_y, sp->shp_own));
 330     }
 331
 332     return 1;
 333 }
 334
 335 char *
 336 prsub(struct shpstr *sp)
 337 {
 338     if (mchr[(int)sp->shp_type].m_flags & M_SUB)
 339         return "sub";
 340     else
 341         return prship(sp);
 342 }