games/trek/torped.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  * @(#)torped.c 8.1 (Berkeley) 5/31/93
  30  * $FreeBSD: src/games/trek/torped.c,v 1.5 1999/11/30 03:49:55 billf Exp $
  31  * $DragonFly: src/games/trek/torped.c,v 1.3 2006/09/07 21:19:44 pavalos Exp $
  32  */
  33
  34 #include "trek.h"
  35 #include "getpar.h"
  36
  37 static int randcourse(int);
  38
  39 /*
  40 **  PHOTON TORPEDO CONTROL
  41 **
  42 **      Either one or three photon torpedoes are fired.  If three
  43 **      are fired, it is called a "burst" and you also specify
  44 **      a spread angle.
  45 **
  46 **      Torpedoes are never 100% accurate.  There is always a random
  47 **      cludge factor in their course which is increased if you have
  48 **      your shields up.  Hence, you will find that they are more
  49 **      accurate at close range.  However, they have the advantage that
  50 **      at long range they don't lose any of their power as phasers
  51 **      do, i.e., a hit is a hit is a hit, by any other name.
  52 **
  53 **      When the course spreads too much, you get a misfire, and the
  54 **      course is randomized even more.  You also have the chance that
  55 **      the misfire damages your torpedo tubes.
  56 */
  57
  58 void
  59 torped(int v __unused)
  60 {
  61         int             ix, iy;
  62         double          x, y, dx, dy;
  63         double          angle;
  64         int             course, course2;
  65         int             k;
  66         double          bigger;
  67         double          sectsize;
  68         int             burst;
  69         int             n;
  70
  71         if (Ship.cloaked) {
  72                 printf("Federation regulations do not permit attack while cloaked.\n");
  73                 return;
  74         }
  75         if (check_out(TORPED))
  76                 return;
  77         if (Ship.torped <= 0) {
  78                 printf("All photon torpedos expended\n");
  79                 return;
  80         }
  81
  82         /* get the course */
  83         course = getintpar("Torpedo course");
  84         if (course < 0 || course > 360)
  85                 return;
  86         burst = -1;
  87
  88         /* need at least three torpedoes for a burst */
  89         if (Ship.torped < 3) {
  90                 printf("No-burst mode selected\n");
  91                 burst = 0;
  92         } else {
  93                 /* see if the user wants one */
  94                 if (!testnl()) {
  95                         k = ungetc(cgetc(0), stdin);
  96                         if (k >= '0' && k <= '9')
  97                                 burst = 1;
  98                 }
  99         }
 100         if (burst < 0) {
 101                 burst = getynpar("Do you want a burst");
 102         }
 103         if (burst) {
 104                 burst = getintpar("burst angle");
 105                 if (burst <= 0)
 106                         return;
 107                 if (burst > 15) {
 108                         printf("Maximum burst angle is 15 degrees\n");
 109                         return;
 110                 }
 111         }
 112         sectsize = NSECTS;
 113         n = -1;
 114         if (burst) {
 115                 n = 1;
 116                 course -= burst;
 117         }
 118         for (; n && n <= 3; n++) {
 119                 /* select a nice random course */
 120                 course2 = course + randcourse(n);
 121                 angle = course2 * 0.0174532925;                 /* convert to radians */
 122                 dx = -cos(angle);
 123                 dy =  sin(angle);
 124                 bigger = fabs(dx);
 125                 x = fabs(dy);
 126                 if (x > bigger)
 127                         bigger = x;
 128                 dx /= bigger;
 129                 dy /= bigger;
 130                 x = Ship.sectx + 0.5;
 131                 y = Ship.secty + 0.5;
 132                 if (Ship.cond != DOCKED)
 133                         Ship.torped -= 1;
 134                 printf("Torpedo track");
 135                 if (n > 0)
 136                         printf(", torpedo number %d", n);
 137                 printf(":\n%6.1f\t%4.1f\n", x, y);
 138                 while (1) {
 139                         ix = x += dx;
 140                         iy = y += dy;
 141                         if (x < 0.0 || x >= sectsize ||
 142                             y < 0.0 || y >= sectsize) {
 143                                 printf("Torpedo missed\n");
 144                                 break;
 145                         }
 146                         printf("%6.1f\t%4.1f\n", x, y);
 147                         switch (Sect[ix][iy]) {
 148                           case EMPTY:
 149                                 continue;
 150
 151                           case HOLE:
 152                                 printf("Torpedo disappears into a black hole\n");
 153                                 break;
 154
 155                           case KLINGON:
 156                                 for (k = 0; k < Etc.nkling; k++) {
 157                                         if (Etc.klingon[k].x != ix || Etc.klingon[k].y != iy)
 158                                                 continue;
 159                                         Etc.klingon[k].power -= 500 + ranf(501);
 160                                         if (Etc.klingon[k].power > 0) {
 161                                                 printf("*** Hit on Klingon at %d,%d: extensive damages\n",
 162                                                         ix, iy);
 163                                                 break;
 164                                         }
 165                                         killk(ix, iy);
 166                                         break;
 167                                 }
 168                                 break;
 169
 170                           case STAR:
 171                                 nova(ix, iy);
 172                                 break;
 173
 174                           case INHABIT:
 175                                 kills(ix, iy, -1);
 176                                 break;
 177
 178                           case BASE:
 179                                 killb(Ship.quadx, Ship.quady);
 180                                 Game.killb += 1;
 181                                 break;
 182                           default:
 183                                 printf("Unknown object %c at %d,%d destroyed\n",
 184                                         Sect[ix][iy], ix, iy);
 185                                 Sect[ix][iy] = EMPTY;
 186                                 break;
 187                         }
 188                         break;
 189                 }
 190                 if (damaged(TORPED) || Quad[Ship.quadx][Ship.quady].stars < 0)
 191                         break;
 192                 course += burst;
 193         }
 194         Move.free = 0;
 195 }
 196
 197
 198 /*
 199 **  RANDOMIZE COURSE
 200 **
 201 **      This routine randomizes the course for torpedo number 'n'.
 202 **      Other things handled by this routine are misfires, damages
 203 **      to the tubes, etc.
 204 */
 205
 206 static int
 207 randcourse(int n)
 208 {
 209         double                  r;
 210         int             d;
 211
 212         d = ((franf() + franf()) - 1.0) * 20;
 213         if (abs(d) > 12) {
 214                 printf("Photon tubes misfire");
 215                 if (n < 0)
 216                         printf("\n");
 217                 else
 218                         printf(" on torpedo %d\n", n);
 219                 if (ranf(2)) {
 220                         damage(TORPED, 0.2 * abs(d) * (franf() + 1.0));
 221                 }
 222                 d *= 1.0 + 2.0 * franf();
 223         }
 224         if (Ship.shldup || Ship.cond == DOCKED) {
 225                 r = Ship.shield;
 226                 r = 1.0 + r / Param.shield;
 227                 if (Ship.cond == DOCKED)
 228                         r = 2.0;
 229                 d *= r;
 230         }
 231         return (d);
 232 }