games/trek/schedule.c

   1 /*      $NetBSD: schedule.c,v 1.10 2009/05/24 21:44:56 dholland Exp $   */
   2
   3 /*
   4  * Copyright (c) 1980, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 #include <sys/cdefs.h>
  33 #ifndef lint
  34 #if 0
  35 static char sccsid[] = "@(#)schedule.c  8.1 (Berkeley) 5/31/93";
  36 #else
  37 __RCSID("$NetBSD: schedule.c,v 1.10 2009/05/24 21:44:56 dholland Exp $");
  38 #endif
  39 #endif /* not lint */
  40
  41 #include <stdio.h>
  42 #include <math.h>
  43 #include <err.h>
  44 #include <limits.h>
  45 #include "trek.h"
  46
  47 /*
  48 **  SCHEDULE AN EVENT
  49 **
  50 **      An event of type 'type' is scheduled for time NOW + 'offset'
  51 **      into the first available slot.  'x', 'y', and 'z' are
  52 **      considered the attributes for this event.
  53 **
  54 **      The address of the slot is returned.
  55 */
  56
  57 struct event *
  58 schedule(int type, double offset, int x, int y, int z)
  59 {
  60         struct event    *e;
  61         int             i;
  62         double                  date;
  63
  64         date = Now.date + offset;
  65         for (i = 0; i < MAXEVENTS; i++) {
  66                 e = &Event[i];
  67                 if (e->evcode)
  68                         continue;
  69                 /* got a slot */
  70 #ifdef xTRACE
  71                 if (Trace)
  72                         printf("schedule: type %d @ %.2f "
  73                                "slot %d parm %d %d %d\n",
  74                                 type, date, i, x, y, z);
  75 #endif
  76                 e->evcode = type;
  77                 e->date = date;
  78                 e->x = x;
  79                 e->y = y;
  80                 e->systemname = z;
  81                 Now.eventptr[type & ~E_GHOST] = e;
  82                 return (e);
  83         }
  84         errx(1, "Cannot schedule event %d parm %d %d %d", type, x, y, z);
  85 }
  86
  87
  88 /*
  89 **  RESCHEDULE AN EVENT
  90 **
  91 **      The event pointed to by 'e' is rescheduled to the current
  92 **      time plus 'offset'.
  93 */
  94
  95 void
  96 reschedule(struct event *e1, double offset)
  97 {
  98         double                  date;
  99         struct event    *e;
 100
 101         e = e1;
 102
 103         date = Now.date + offset;
 104         e->date = date;
 105 #ifdef xTRACE
 106         if (Trace)
 107                 printf("reschedule: type %d parm %d %d %d @ %.2f\n",
 108                         e->evcode, e->x, e->y, e->systemname, date);
 109 #endif
 110         return;
 111 }
 112
 113
 114 /*
 115 **  UNSCHEDULE AN EVENT
 116 **
 117 **      The event at slot 'e' is deleted.
 118 */
 119
 120 void
 121 unschedule(struct event *e1)
 122 {
 123         struct event    *e;
 124
 125         e = e1;
 126
 127 #ifdef xTRACE
 128         if (Trace)
 129                 printf("unschedule: type %d @ %.2f parm %d %d %d\n",
 130                         e->evcode, e->date, e->x, e->y, e->systemname);
 131 #endif
 132         Now.eventptr[e->evcode & E_EVENT] = 0;
 133         e->date = TOOLARGE;
 134         e->evcode = 0;
 135         return;
 136 }
 137
 138
 139 /*
 140 **  Abreviated schedule routine
 141 **
 142 **      Parameters are the event index and a factor for the time
 143 **      figure.
 144 */
 145
 146 struct event *
 147 xsched(int ev1, int factor, int x, int y, int z)
 148 {
 149         int     ev;
 150         double when;
 151
 152         ev = ev1;
 153         when = -Param.eventdly[ev] * Param.time * log(franf()) / factor;
 154         return (schedule(ev, when, x, y, z));
 155 }
 156
 157
 158 /*
 159 **  Simplified reschedule routine
 160 **
 161 **      Parameters are the event index, the initial date, and the
 162 **      division factor.  Look at the code to see what really happens.
 163 */
 164
 165 void
 166 xresched(struct event *e1, int ev1, int factor)
 167 {
 168         int             ev;
 169         struct event    *e;
 170         double when;
 171
 172         ev = ev1;
 173         e = e1;
 174         when = -Param.eventdly[ev] * Param.time * log(franf()) / factor;
 175         reschedule(e, when);
 176 }