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