games/sail/misc.c

   1 /*
   2  * Copyright (c) 1983, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  * @(#)misc.c   8.1 (Berkeley) 5/31/93
  34  * $FreeBSD: src/games/sail/misc.c,v 1.5 1999/11/30 03:49:34 billf Exp $
  35  * $DragonFly: src/games/sail/misc.c,v 1.4 2006/09/03 17:33:13 pavalos Exp $
  36  */
  37
  38 #include "externs.h"
  39 #include "pathnames.h"
  40
  41 #define distance(x,y) (abs(x) >= abs(y) ? abs(x) + abs(y)/2 : abs(y) + abs(x)/2)
  42
  43 static int      angle(int, int);
  44
  45 /* XXX */
  46 int
  47 range(struct ship *from, struct ship *to)
  48 {
  49         int bow1r, bow1c, bow2r, bow2c;
  50         int stern1r, stern1c, stern2c, stern2r;
  51         int bb, bs, sb, ss, result;
  52
  53         if (!to->file->dir)
  54                 return -1;
  55         stern1r = bow1r = from->file->row;
  56         stern1c = bow1c = from->file->col;
  57         stern2r = bow2r = to->file->row;
  58         stern2c = bow2c = to->file->col;
  59         result = bb = distance(bow2r - bow1r, bow2c - bow1c);
  60         if (bb < 5) {
  61                 stern2r += dr[to->file->dir];
  62                 stern2c += dc[to->file->dir];
  63                 stern1r += dr[from->file->dir];
  64                 stern1c += dc[from->file->dir];
  65                 bs = distance((bow2r - stern1r), (bow2c - stern1c));
  66                 sb = distance((bow1r - stern2r), (bow1c - stern2c));
  67                 ss = distance((stern2r - stern1r) ,(stern2c - stern1c));
  68                 result = min(bb, min(bs, min(sb, ss)));
  69         }
  70         return result;
  71 }
  72
  73 struct ship *
  74 closestenemy(struct ship *from, char side, char anyship)
  75 {
  76         struct ship *sp;
  77         char a;
  78         int olddist = 30000, dist;
  79         struct ship *closest = 0;
  80
  81         a = capship(from)->nationality;
  82         foreachship(sp) {
  83                 if (sp == from)
  84                         continue;
  85                 if (sp->file->dir == 0)
  86                         continue;
  87                 if (a == capship(sp)->nationality && !anyship)
  88                         continue;
  89                 if (side && gunsbear(from, sp) != side)
  90                         continue;
  91                 dist = range(from, sp);
  92                 if (dist < olddist) {
  93                         closest = sp;
  94                         olddist = dist;
  95                 }
  96         }
  97         return closest;
  98 }
  99
 100 static int
 101 angle(int Dr, int Dc)
 102 {
 103         int i;
 104
 105         if (Dc >= 0 && Dr > 0)
 106                 i = 0;
 107         else if (Dr <= 0 && Dc > 0)
 108                 i = 2;
 109         else if (Dc <= 0 && Dr < 0)
 110                 i = 4;
 111         else
 112                 i = 6;
 113         Dr = abs(Dr);
 114         Dc = abs(Dc);
 115         if ((i == 0 || i == 4) && Dc * 2.4 > Dr) {
 116                 i++;
 117                 if (Dc > Dr * 2.4)
 118                         i++;
 119         } else if ((i == 2 || i == 6) && Dr * 2.4 > Dc) {
 120                 i++;
 121                 if (Dr > Dc * 2.4)
 122                         i++;
 123         }
 124         return i % 8 + 1;
 125 }
 126
 127 char
 128 gunsbear(struct ship *from, struct ship *to)    /* checks for target bow or stern */
 129 {
 130         int Dr, Dc, i;
 131         int ang;
 132
 133         Dr = from->file->row - to->file->row;
 134         Dc = to->file->col - from->file->col;
 135         for (i = 2; i; i--) {
 136                 if ((ang = angle(Dr, Dc) - from->file->dir + 1) < 1)
 137                         ang += 8;
 138                 if (ang >= 2 && ang <= 4)
 139                         return 'r';
 140                 if (ang >= 6 && ang <= 7)
 141                         return 'l';
 142                 Dr += dr[to->file->dir];
 143                 Dc += dc[to->file->dir];
 144         }
 145         return 0;
 146 }
 147
 148 int
 149 portside(struct ship *from, struct ship *on, int quick)
 150                                 /* returns true if fromship is */
 151 {                               /* shooting at onship's starboard side */
 152         int ang;
 153         int Dr, Dc;
 154
 155         Dr = from->file->row - on->file->row;
 156         Dc = on->file->col - from->file->col;
 157         if (quick == -1) {
 158                 Dr += dr[on->file->dir];
 159                 Dc += dc[on->file->dir];
 160         }
 161         ang = angle(Dr, Dc);
 162         if (quick != 0)
 163                 return ang;
 164         ang = (ang + 4 - on->file->dir - 1) % 8 + 1;
 165         return ang < 5;
 166 }
 167
 168 char
 169 colours(struct ship *sp)
 170 {
 171         char flag = 0;
 172
 173         if (sp->file->struck)
 174                 flag = '!';
 175         if (sp->file->explode)
 176                 flag = '#';
 177         if (sp->file->sink)
 178                 flag = '~';
 179         if (sp->file->struck)
 180                 return flag;
 181         flag = *countryname[capship(sp)->nationality];
 182         return sp->file->FS ? flag : tolower(flag);
 183 }
 184
 185 #include <sys/file.h>
 186 void
 187 write_log(struct ship *s)
 188 {
 189         FILE *fp;
 190         int persons;
 191         int n;
 192         struct logs log[NLOG];
 193         float net;
 194         struct logs *lp;
 195
 196         if ((fp = fopen(_PATH_LOGFILE, "r+")) == NULL)
 197                 return;
 198 #ifdef LOCK_EX
 199         if (flock(fileno(fp), LOCK_EX) < 0)
 200                 return;
 201 #endif
 202         net = (float)s->file->points / s->specs->pts;
 203         persons = getw(fp);
 204         n = fread((char *)log, sizeof(struct logs), NLOG, fp);
 205         for (lp = &log[n]; lp < &log[NLOG]; lp++)
 206                 lp->l_name[0] = lp->l_uid = lp->l_shipnum
 207                         = lp->l_gamenum = lp->l_netpoints = 0;
 208         rewind(fp);
 209         if (persons < 0)
 210                 putw(1, fp);
 211         else
 212                 putw(persons + 1, fp);
 213         for (lp = log; lp < &log[NLOG]; lp++)
 214                 if (net > (float)lp->l_netpoints
 215                     / scene[lp->l_gamenum].ship[lp->l_shipnum].specs->pts) {
 216                         fwrite((char *)log,
 217                                 sizeof (struct logs), lp - log, fp);
 218                         strcpy(log[NLOG-1].l_name, s->file->captain);
 219                         log[NLOG-1].l_uid = getuid();
 220                         log[NLOG-1].l_shipnum = s->file->index;
 221                         log[NLOG-1].l_gamenum = game;
 222                         log[NLOG-1].l_netpoints = s->file->points;
 223                         fwrite((char *)&log[NLOG-1],
 224                                 sizeof (struct logs), 1, fp);
 225                         fwrite((char *)lp,
 226                                 sizeof (struct logs), &log[NLOG-1] - lp, fp);
 227                         break;
 228                 }
 229 #ifdef LOCK_EX
 230         flock(fileno(fp), LOCK_UN);
 231 #endif
 232         fclose(fp);
 233 }