games/trek/klmove.c

   1 /*-
   2  * Copyright (c) 1980, 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  * @(#)klmove.c 8.1 (Berkeley) 5/31/93
  30  * $FreeBSD: src/games/trek/klmove.c,v 1.4 1999/11/30 03:49:49 billf Exp $
  31  * $DragonFly: src/games/trek/klmove.c,v 1.4 2006/10/08 17:11:30 pavalos Exp $
  32  */
  33
  34 #include "trek.h"
  35
  36 /*
  37 **  Move Klingons Around
  38 **
  39 **      This is a largely incomprehensible block of code that moves
  40 **      Klingons around in a quadrant.  It was written in a very
  41 **      "program as you go" fashion, and is a prime candidate for
  42 **      rewriting.
  43 **
  44 **      The flag `fl' is zero before an attack, one after an attack,
  45 **      and two if you are leaving a quadrant.  This serves to
  46 **      change the probability and distance that it moves.
  47 **
  48 **      Basically, what it will try to do is to move a certain number
  49 **      of steps either toward you or away from you.  It will avoid
  50 **      stars whenever possible.  Nextx and nexty are the next
  51 **      sector to move to on a per-Klingon basis; they are roughly
  52 **      equivalent to Ship.sectx and Ship.secty for the starship.  Lookx and
  53 **      looky are the sector that you are going to look at to see
  54 **      if you can move their.  Dx and dy are the increment.  Fudgex
  55 **      and fudgey are the things you change around to change your
  56 **      course around stars.
  57 */
  58
  59 void
  60 klmove(int fl)
  61 {
  62         int                     n;
  63         struct kling    *k;
  64         double                  dx, dy;
  65         int                     nextx, nexty;
  66         int             lookx, looky;
  67         int                     motion;
  68         int                     fudgex, fudgey;
  69         int                     qx, qy;
  70         double                  bigger;
  71         int                     i;
  72
  73 #ifdef xTRACE
  74         if (Trace)
  75                 printf("klmove: fl = %d, Etc.nkling = %d\n", fl, Etc.nkling);
  76 #endif
  77         for (n = 0; n < Etc.nkling; n++) {
  78                 k = &Etc.klingon[n];
  79                 i = 100;
  80                 if (fl)
  81                         i = 100.0 * k->power / Param.klingpwr;
  82                 if (ranf(i) >= Param.moveprob[2 * Move.newquad + fl])
  83                         continue;
  84                 /* compute distance to move */
  85                 motion = ranf(75) - 25;
  86                 motion *= k->avgdist * Param.movefac[2 * Move.newquad + fl];
  87                 /* compute direction */
  88                 dx = Ship.sectx - k->x + ranf(3) - 1;
  89                 dy = Ship.secty - k->y + ranf(3) - 1;
  90                 bigger = dx;
  91                 if (dy > bigger)
  92                         bigger = dy;
  93                 if (bigger == 0.0)
  94                         bigger = 1.0;
  95                 dx = dx / bigger + 0.5;
  96                 dy = dy / bigger + 0.5;
  97                 if (motion < 0) {
  98                         motion = -motion;
  99                         dx = -dx;
 100                         dy = -dy;
 101                 }
 102                 fudgex = fudgey = 1;
 103                 /* try to move the klingon */
 104                 nextx = k->x;
 105                 nexty = k->y;
 106                 for (; motion > 0; motion--) {
 107                         lookx = nextx + dx;
 108                         looky = nexty + dy;
 109                         if (lookx < 0 || lookx >= NSECTS ||
 110                             looky < 0 || looky >= NSECTS) {
 111                                 /* new quadrant */
 112                                 qx = Ship.quadx;
 113                                 qy = Ship.quady;
 114                                 if (lookx < 0)
 115                                         qx -= 1;
 116                                 else
 117                                         if (lookx >= NSECTS)
 118                                                 qx += 1;
 119                                 if (looky < 0)
 120                                         qy -= 1;
 121                                 else
 122                                         if (looky >= NSECTS)
 123                                                 qy += 1;
 124                                 if (qx < 0 || qx >= NQUADS ||
 125                                     qy < 0 || qy >= NQUADS ||
 126                                     Quad[qx][qy].stars < 0 ||
 127                                     Quad[qx][qy].klings > MAXKLQUAD - 1)
 128                                         break;
 129                                 if (!damaged(SRSCAN)) {
 130                                         printf("Klingon at %d,%d escapes to quadrant %d,%d\n",
 131                                                 k->x, k->y, qx, qy);
 132                                         motion = Quad[qx][qy].scanned;
 133                                         if (motion >= 0 && motion < 1000)
 134                                                 Quad[qx][qy].scanned += 100;
 135                                         motion = Quad[Ship.quadx][Ship.quady].scanned;
 136                                         if (motion >= 0 && motion < 1000)
 137                                                 Quad[Ship.quadx][Ship.quady].scanned -= 100;
 138                                 }
 139                                 Sect[k->x][k->y] = EMPTY;
 140                                 Quad[qx][qy].klings += 1;
 141                                 Etc.nkling -= 1;
 142                                 bmove(&Etc.klingon[Etc.nkling], k, sizeof *k);
 143                                 Quad[Ship.quadx][Ship.quady].klings -= 1;
 144                                 k = 0;
 145                                 break;
 146                         }
 147                         if (Sect[lookx][looky] != EMPTY) {
 148                                 lookx = nextx + fudgex;
 149                                 if (lookx < 0 || lookx >= NSECTS)
 150                                         lookx = nextx + dx;
 151                                 if (Sect[lookx][looky] != EMPTY) {
 152                                         fudgex = -fudgex;
 153                                         looky = nexty + fudgey;
 154                                         if (looky < 0 || looky >= NSECTS ||
 155                                             Sect[lookx][looky] != EMPTY) {
 156                                                 fudgey = -fudgey;
 157                                                 break;
 158                                         }
 159                                 }
 160                         }
 161                         nextx = lookx;
 162                         nexty = looky;
 163                 }
 164                 if (k && (k->x != nextx || k->y != nexty)) {
 165                         if (!damaged(SRSCAN))
 166                                 printf("Klingon at %d,%d moves to %d,%d\n",
 167                                         k->x, k->y, nextx, nexty);
 168                         Sect[k->x][k->y] = EMPTY;
 169                         Sect[k->x = nextx][k->y = nexty] = KLINGON;
 170                 }
 171         }
 172         compkldist(0);
 173 }