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     struct mchrstr *sub_mcp;
  62     char *ptr;
  63     struct nstr_item nbst;
  64     char buf[1024];
  65     int ntorping = 0;
  66     char prompt[128];
  67
  68     if (!snxtitem(&nbst, EF_SHIP, player->argp[1], "From ship(s)? "))
  69         return RET_SYN;
  70     while (nxtitem(&nbst, &sub)) {
  71         if (sub.shp_own != player->cnum)
  72             continue;
  73         if ((mchr[(int)sub.shp_type].m_flags & M_TORP) == 0)
  74             continue;
  75         if (sub.shp_item[I_GUN] == 0
  76             || sub.shp_item[I_SHELL] < SHP_TORP_SHELLS)
  77             continue;
  78         if (sub.shp_item[I_MILIT] < 1)
  79             continue;
  80         if (sub.shp_effic < 60)
  81             continue;
  82         if (sub.shp_mobil <= 0)
  83             continue;
  84         ntorping++;
  85     }
  86     pr("%d ships are eligible to torpedo\n", ntorping);
  87     snxtitem_rewind(&nbst);
  88     while (nxtitem(&nbst, &sub)) {
  89         if (!sub.shp_own)
  90             continue;
  91         if (sub.shp_own != player->cnum) {
  92             continue;
  93         }
  94         sub_mcp = &mchr[sub.shp_type];
  95         if (!(sub_mcp->m_flags & M_TORP)) {
  96             pr("Ship # %d: A %s can't fire torpedoes!\n",
  97                sub.shp_uid, sub_mcp->m_name);
  98             continue;
  99         }
 100         if (sub.shp_item[I_GUN] == 0
 101             || sub.shp_item[I_SHELL] < SHP_TORP_SHELLS) {
 102             pr("Ship #%d has insufficient armament\n", sub.shp_uid);
 103             continue;
 104         }
 105         if (sub.shp_item[I_MILIT] < 1) {
 106             pr("Ship #%d has insufficient crew\n", sub.shp_uid);
 107             continue;
 108         }
 109         if (sub.shp_effic < 60) {
 110             pr("Ship #%d torpedo tubes inoperative.\n", sub.shp_uid);
 111             continue;
 112         }
 113         if (sub.shp_mobil <= 0) {
 114             pr("Ship #%d has insufficient mobility\n", sub.shp_uid);
 115             continue;
 116         }
 117         subno = sub.shp_uid;
 118         sprintf(prompt, "Ship %d, target? ", sub.shp_uid);
 119         if (!(ptr = getstarg(player->argp[2], prompt, buf)))
 120             return RET_SYN;
 121         if (!check_ship_ok(&sub))
 122             return RET_FAIL;
 123         if ((victno = atoi(ptr)) < 0)
 124             return RET_SYN;
 125         if (!getship(victno, &vship))
 126             return RET_FAIL;
 127         if (!vship.shp_own)
 128             return RET_FAIL;
 129         vshipown = vship.shp_own;
 130         if (victno == subno) {
 131             pr("Shooting yourself, eh?  How strange...\n");
 132             continue;
 133         }
 134         if (mchr[(int)vship.shp_type].m_flags & M_SUB) {
 135             if (!(sub_mcp->m_flags & M_SUBT)) {
 136                 pr("You can't torpedo a submarine!\n");
 137                 continue;
 138             }
 139         }
 140         dam = shp_torp(&sub, 1);
 141         sub.shp_mission = 0;
 142         putship(sub.shp_uid, &sub);
 143         if (CANT_HAPPEN(dam < 0)) {
 144             pr("Ship #%d has insufficient armament\n", sub.shp_uid);
 145             continue;
 146         }
 147
 148         if (!(sub_mcp->m_flags & M_SUB))
 149             anti_torp(sub.shp_uid, ntorping, vshipown);
 150         getship(sub.shp_uid, &sub);
 151         if (sub.shp_own == 0)
 152             continue;
 153
 154         erange = roundrange(torprange(&sub));
 155         pr("Effective torpedo range is %d.0\n", erange);
 156         pr("Whooosh... ");
 157         getship(victno, &vship);
 158         vshipown = vship.shp_own;
 159         range = mapdist(sub.shp_x, sub.shp_y, vship.shp_x, vship.shp_y);
 160         hitchance = shp_torp_hitchance(&sub, range);
 161         if (range <= erange) {
 162             pr("Hitchance = %d%%\n", (int)(hitchance * 100));
 163         }
 164         /* Now, can the torpedo even get there? */
 165         if (!line_of_sight(NULL, sub.shp_x, sub.shp_y,
 166                            vship.shp_x, vship.shp_y)) {
 167             pr("BOOM!... Torpedo slams into land before reaching target.\n");
 168             /* We only tell the victim if we were within range. */
 169             if (range <= erange) {
 170                 if (vshipown != 0)
 171                     wu(0, vshipown, "Torpedo sighted @ %s by %s\n",
 172                        xyas(sub.shp_x, sub.shp_y, vshipown),
 173                        prship(&vship));
 174             }
 175         } else if (range > erange) {
 176             pr("Out of range\n");
 177         } else if (chance(hitchance)) {
 178             pr("BOOM!...\n");
 179             if (vshipown != 0)
 180                 wu(0, vshipown, "%s in %s torpedoed %s for %d damage.\n",
 181                    prsub(&sub), xyas(sub.shp_x, sub.shp_y, vshipown),
 182                    prship(&vship), dam);
 183             pr("Torpedo hit %s for %d damage.\n", prsub(&vship), dam);
 184             if (!(mchr[vship.shp_type].m_flags & M_SUB)) {
 185                 if (mchr[sub.shp_type].m_flags & M_SUB)
 186                     nreport(vshipown, N_TORP_SHIP, 0, 1);
 187                 else
 188                     nreport(vshipown, N_SHIP_TORP, player->cnum, 1);
 189             }
 190             shipdamage(&vship, dam);
 191             if (vship.shp_effic < SHIP_MINEFF)
 192                 pr("%s sunk!\n", prsub(&vship));
 193             putship(vship.shp_uid, &vship);
 194             if (vship.shp_rflags & RET_TORPED)
 195                 retreat_ship(&vship, vshipown, 't');
 196         } else {
 197             pr("Missed\n");
 198             if (vshipown != 0)
 199                 wu(0, vshipown, "Torpedo sighted @ %s by %s\n",
 200                    xyas(sub.shp_x, sub.shp_y, vshipown), prship(&vship));
 201         }
 202
 203         if (sub_mcp->m_flags & M_SUB)
 204             anti_torp(sub.shp_uid, ntorping, vshipown);
 205     }
 206     return RET_OK;
 207 }
 208
 209 static void
 210 anti_torp(int f, int ntorping, int vshipown)
 211 {
 212     struct shpstr sub;
 213     struct shpstr dd;
 214     int x;
 215
 216     getship(f, &sub);
 217
 218     if (sub.shp_own == vshipown)
 219         return;
 220
 221     if ((mchr[(int)sub.shp_type].m_flags & M_SUB) == 0)
 222         pr("Starting our attack run...\n");
 223
 224     x = 0;
 225     while (getship(x++, &dd) && sub.shp_effic >= SHIP_MINEFF) {
 226         if (dd.shp_own == 0)
 227             continue;
 228         if (dd.shp_own != vshipown)
 229             continue;
 230
 231         if (!fire_torp(&dd, &sub, ntorping))
 232             fire_dchrg(&dd, &sub, ntorping);
 233     }
 234 }
 235
 236 static void
 237 fire_dchrg(struct shpstr *sp, struct shpstr *targ, int ntargets)
 238 {
 239     int range, erange, dam;
 240
 241     erange = roundrange(shp_fire_range(sp));
 242     range = mapdist(sp->shp_x, sp->shp_y, targ->shp_x, targ->shp_y);
 243     if (range > erange)
 244         return;
 245
 246     if ((mchr[(int)targ->shp_type].m_flags & M_SUB) == 0) {
 247         /* Return fire to a torpedo boat */
 248         if (mchr[sp->shp_type].m_flags & M_SUB)
 249             return;             /* sub deck gun can't return fire */
 250         dam = shp_fire(sp);
 251         putship(sp->shp_uid, sp);
 252         if (dam < 0)
 253             return;
 254         if (ntargets > 2)
 255             dam /= ntargets / 2;
 256
 257         pr_beep();
 258         pr("Kaboom!!! Incoming shells!\n");
 259         if (sp->shp_own != 0)
 260             wu(0, sp->shp_own,
 261                "%s fired at %s\n", prship(sp), prship(targ));
 262         pr_beep();
 263         pr("BLAM! %d damage!\n", dam);
 264     } else {
 265         /* Return fire to a submarine */
 266         dam = shp_dchrg(sp);
 267         putship(sp->shp_uid, sp);
 268         if (dam < 0)
 269             return;
 270         if (ntargets > 2)
 271             dam /= ntargets / 2;
 272
 273         pr("\nCAPTAIN!  !!Depth charges!!...\n");
 274         if (sp->shp_own != 0)
 275             wu(0, sp->shp_own,
 276                "%s depth charged %s\n", prship(sp), prsub(targ));
 277         pr("click...WHAM!  %d damage!\n", dam);
 278     }
 279     shipdamage(targ, dam);
 280     putship(targ->shp_uid, targ);
 281 }
 282
 283 static int
 284 fire_torp(struct shpstr *sp, struct shpstr *targ, int ntargets)
 285 {
 286     int range, erange, dam;
 287
 288     if ((mchr[targ->shp_type].m_flags & M_SUB)
 289         && (mchr[sp->shp_type].m_flags & M_SUBT) == 0)
 290         return 0;               /* need sub-torp to torpedo a sub */
 291
 292     erange = roundrange(torprange(sp));
 293     range = mapdist(sp->shp_x, sp->shp_y, targ->shp_x, targ->shp_y);
 294     if (range > erange)
 295         return 0;
 296
 297     if (!line_of_sight(NULL, sp->shp_x, sp->shp_y,
 298                        targ->shp_x, targ->shp_y))
 299         return 0;
 300     dam = shp_torp(sp, 1);
 301     putship(sp->shp_uid, sp);
 302     if (dam < 0)
 303         return 0;
 304
 305     pr("Captain! Torpedoes sighted!\n");
 306
 307     if (chance(shp_torp_hitchance(sp, range))) {
 308         pr("BOOM!...\n");
 309         if (!(mchr[targ->shp_type].m_flags & M_SUB)) {
 310             if (mchr[sp->shp_type].m_flags & M_SUB)
 311                 nreport(targ->shp_own, N_TORP_SHIP, 0, 1);
 312             else
 313                 nreport(targ->shp_own, N_SHIP_TORP, sp->shp_own, 1);
 314         }
 315         if (sp->shp_own != 0)
 316             wu(0, sp->shp_own, "%s @ %s torpedoed %s\n",
 317                prship(sp),
 318                xyas(sp->shp_x, sp->shp_y, sp->shp_own), prsub(targ));
 319         if (ntargets > 2)
 320             dam /= ntargets / 2;
 321
 322         shipdamage(targ, dam);
 323         putship(targ->shp_uid, targ);
 324
 325     } else {
 326         pr("Missed!\n");
 327         if (sp->shp_own != 0)
 328             wu(0, sp->shp_own,
 329                "%s missed %s with a torpedo at %s\n",
 330                prship(sp), prsub(targ),
 331                xyas(sp->shp_x, sp->shp_y, sp->shp_own));
 332     }
 333
 334     return 1;
 335 }
 336
 337 char *
 338 prsub(struct shpstr *sp)
 339 {
 340     if (mchr[(int)sp->shp_type].m_flags & M_SUB)
 341         return "sub";
 342     else
 343         return prship(sp);
 344 }