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

   1 /*
   2  *  Empire - A multi-player, client/server Internet based war game.
   3  *  Copyright (C) 1986-2000, Dave Pare, Jeff Bailey, Thomas Ruschak,
   4  *                           Ken Stevens, Steve McClure
   5  *
   6  *  This program 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 2 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, write to the Free Software
  18  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  *
  20  *  ---
  21  *
  22  *  See the "LEGAL", "LICENSE", "CREDITS" and "README" files for all the
  23  *  related information and legal notices. It is expected that any future
  24  *  projects/authors will amend these files as needed.
  25  *
  26  *  ---
  27  *
  28  *  coas.c: Look at all the ships in the world
  29  *
  30  *  Known contributors to this file:
  31  *     Keith Muller, 1983
  32  *     Dave Pare, 1986 (rewrite)
  33  */
  34
  35 #include "misc.h"
  36 #include "player.h"
  37 #include "var.h"
  38 #include "sect.h"
  39 #include "ship.h"
  40 #include "nat.h"
  41 #include "xy.h"
  42 #include "nsc.h"
  43 #include "file.h"
  44 #include "commands.h"
  45 #include "optlist.h"
  46
  47 #define TSIZE   200
  48
  49 struct coast {
  50         struct coast *c_next;
  51         int c_spotted;
  52         int c_number;
  53         struct shpstr c_shp;
  54 };
  55
  56 static  int showship(struct coast **cpp, int x, int y);
  57
  58 /*
  59  * format: coastwatch [<SECTS>]
  60  */
  61 int
  62 coas(void)
  63 {
  64         struct sctstr sect;
  65         struct nstr_sect nstr;
  66         struct coast *cp;
  67         struct coast *list[TSIZE];
  68         int i, k, j, n;
  69         int vrange, see;
  70         int x, y;
  71         int mink, minj, maxk, maxj;
  72         int nship = 0;
  73         float tech;
  74         struct  nstr_item ni;
  75
  76         if (snxtsct(&nstr, player->argp[1]) == 0)
  77                 return RET_SYN;
  78         for (i = 0; i < TSIZE; i++)
  79                 list[i] = 0;
  80         cp = (struct coast *)malloc(sizeof(*cp));
  81         snxtitem_all(&ni, EF_SHIP);
  82         while (nxtitem(&ni, (s_char *) &cp->c_shp)) {
  83                 if (cp->c_shp.shp_own == 0 || cp->c_shp.shp_own == player->cnum)
  84                         continue;
  85                 /*
  86                  * don't bother putting subs in the table...
  87                  * unless they're in a sector you own (harbor or such)
  88                  */
  89                 getsect(cp->c_shp.shp_x, cp->c_shp.shp_y, &sect);
  90                 if ((mchr[(int)cp->c_shp.shp_type].m_flags & M_SUB) &&
  91                         (sect.sct_own != player->cnum))
  92                         continue;
  93                 n = scthash(cp->c_shp.shp_x, cp->c_shp.shp_y, TSIZE);
  94                 cp->c_spotted = 0;
  95                 cp->c_number = i;
  96                 cp->c_next = list[n];
  97                 list[n] = cp;
  98                 cp = (struct coast *)malloc(sizeof(*cp));
  99                 nship++;
 100         }
 101         /* get that last one! */
 102         free((s_char *)cp);
 103         pr("- = [ Coastwatch report for %s ] = -\n", cname(player->cnum));
 104         pr("  Country            Ship          Location\n");
 105         tech = tfact(player->cnum, 1.0);
 106         while (nxtsct(&nstr, &sect) && nship) {
 107                 if (sect.sct_own != player->cnum)
 108                         continue;
 109                 see = sect.sct_type == SCT_RADAR ? 14 : 4;
 110                 vrange = (int) (sect.sct_effic / 100.0 * see * tech);
 111                 if (vrange < 1)
 112                         vrange = 1;
 113                 maxk = vrange;
 114                 maxj = vrange * 2;
 115                 vrange *= vrange;
 116                 mink = -maxk;
 117                 minj = -maxj;
 118                 for (j = minj; j <= maxj && nship; j++) {
 119                         x = xnorm(sect.sct_x + j);
 120                         for (k = mink; k <= maxk && nship; k++) {
 121                                 if ((j + k) & 01)
 122                                          continue;
 123                                 /* quick range check to save time... */
 124                                 if (vrange < (j * j + 3 * k * k) / 4)
 125                                         continue;
 126                                 y = ynorm(sect.sct_y + k);
 127                                 n = scthash(x, y, TSIZE);
 128                                 if (list[n] == 0)
 129                                         continue;
 130                                 nship -= showship(&list[n], x, y);
 131                         }
 132                 }
 133         }
 134         /* free up the coast structs calloc'ed above */
 135         for (i = 0; i < TSIZE; i++) {
 136                 while (NULL != (cp = list[i])) {
 137                         list[i] = cp->c_next;
 138                         free((s_char *)cp);
 139                 }
 140         }
 141         return RET_OK;
 142 }
 143
 144 static int
 145 showship(struct coast **cpp, int x, int y)
 146 {
 147         register struct coast *cp;
 148         register struct coast *todelete = 0;
 149         register struct coast **prev;
 150         int     nship = 0;
 151
 152         prev = 0;
 153         cp = *cpp;
 154         prev = cpp;
 155         do {
 156                 /* we delete it, we free it. */
 157                 if (todelete) {
 158                         free((s_char *)todelete);
 159                         todelete = 0;
 160                 }
 161                 if (cp->c_shp.shp_x != x || cp->c_shp.shp_y != y) {
 162                         prev = &(*prev)->c_next;
 163                         continue;
 164                 }
 165                 pr(" %12.12s (#%3d) %s @ %s\n",
 166                    cname(cp->c_shp.shp_own), cp->c_shp.shp_own,
 167                    prship(&cp->c_shp), xyas(x, y, player->cnum));
 168                 if (opt_HIDDEN) {
 169                     setcont(player->cnum, cp->c_shp.shp_own, FOUND_COAST);
 170                 }
 171                 *prev = cp->c_next;
 172                 todelete = cp;
 173                 nship++;
 174         } while (NULL != (cp = cp->c_next));
 175         /* check that last one! */
 176         if (todelete)
 177                 free((s_char *)todelete);
 178         return (nship);
 179 }