1 /* $NetBSD: move.c,v 1.10 2009/05/24 22:55:03 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[] = "@(#)move.c 8.1 (Berkeley) 5/31/93"; 36 #else 37 __RCSID("$NetBSD: move.c,v 1.10 2009/05/24 22:55:03 dholland Exp $"); 38 #endif 39 #endif /* not lint */ 40 41 #include <stdio.h> 42 #include <math.h> 43 #include "trek.h" 44 45 /* 46 ** Move Under Warp or Impulse Power 47 ** 48 ** `Ramflag' is set if we are to be allowed to ram stars, 49 ** Klingons, etc. This is passed from warp(), which gets it from 50 ** either play() or ram(). Course is the course (0 -> 360) at 51 ** which we want to move. `Speed' is the speed we 52 ** want to go, and `time' is the expected time. It 53 ** can get cut short if a long range tractor beam is to occur. We 54 ** cut short the move so that the user doesn't get docked time and 55 ** energy for distance which he didn't travel. 56 ** 57 ** We check the course through the current quadrant to see that he 58 ** doesn't run into anything. After that, though, space sort of 59 ** bends around him. Note that this puts us in the awkward posi- 60 ** tion of being able to be dropped into a sector which is com- 61 ** pletely surrounded by stars. Oh Well. 62 ** 63 ** If the SINS (Space Inertial Navigation System) is out, we ran- 64 ** domize the course accordingly before ever starting to move. 65 ** We will still move in a straight line. 66 ** 67 ** Note that if your computer is out, you ram things anyway. In 68 ** other words, if your computer and sins are both out, you're in 69 ** potentially very bad shape. 70 ** 71 ** Klingons get a chance to zap you as you leave the quadrant. 72 ** By the way, they also try to follow you (heh heh). 73 ** 74 ** Return value is the actual amount of time used. 75 ** 76 ** 77 ** Uses trace flag 4. 78 */ 79 80 double 81 move(int ramflag, int course, double time, double speed) 82 { 83 double angle; 84 double x, y, dx, dy; 85 int ix = 0, iy = 0; 86 double bigger; 87 int n; 88 int i; 89 double dist; 90 double sectsize; 91 double xn; 92 double evtime; 93 94 #ifdef xTRACE 95 if (Trace) 96 printf("move: ramflag %d course %d time %.2f speed %.2f\n", 97 ramflag, course, time, speed); 98 #endif 99 sectsize = NSECTS; 100 /* initialize delta factors for move */ 101 angle = course * 0.0174532925; 102 if (damaged(SINS)) 103 angle += Param.navigcrud[1] * (franf() - 0.5); 104 else 105 if (Ship.sinsbad) 106 angle += Param.navigcrud[0] * (franf() - 0.5); 107 dx = -cos(angle); 108 dy = sin(angle); 109 bigger = fabs(dx); 110 dist = fabs(dy); 111 if (dist > bigger) 112 bigger = dist; 113 dx /= bigger; 114 dy /= bigger; 115 116 /* check for long range tractor beams */ 117 /**** TEMPORARY CODE == DEBUGGING ****/ 118 evtime = Now.eventptr[E_LRTB]->date - Now.date; 119 #ifdef xTRACE 120 if (Trace) 121 printf("E.ep = %p, ->evcode = %d, ->date = %.2f, " 122 "evtime = %.2f\n", 123 Now.eventptr[E_LRTB], Now.eventptr[E_LRTB]->evcode, 124 Now.eventptr[E_LRTB]->date, evtime); 125 #endif 126 if (time > evtime && Etc.nkling < 3) { 127 /* then we got a LRTB */ 128 evtime += 0.005; 129 time = evtime; 130 } else 131 evtime = -1.0e50; 132 dist = time * speed; 133 134 /* move within quadrant */ 135 Sect[Ship.sectx][Ship.secty] = EMPTY; 136 x = Ship.sectx + 0.5; 137 y = Ship.secty + 0.5; 138 xn = NSECTS * dist * bigger; 139 n = xn + 0.5; 140 #ifdef xTRACE 141 if (Trace) 142 printf("dx = %.2f, dy = %.2f, xn = %.2f, n = %d\n", 143 dx, dy, xn, n); 144 #endif 145 Move.free = 0; 146 147 for (i = 0; i < n; i++) { 148 ix = (x += dx); 149 iy = (y += dy); 150 #ifdef xTRACE 151 if (Trace) 152 printf("ix = %d, x = %.2f, iy = %d, y = %.2f\n", 153 ix, x, iy, y); 154 #endif 155 if (x < 0.0 || y < 0.0 || x >= sectsize || y >= sectsize) { 156 /* enter new quadrant */ 157 dx = Ship.quadx * NSECTS + Ship.sectx + dx * xn; 158 dy = Ship.quady * NSECTS + Ship.secty + dy * xn; 159 if (dx < 0.0) 160 ix = -1; 161 else 162 ix = dx + 0.5; 163 if (dy < 0.0) 164 iy = -1; 165 else 166 iy = dy + 0.5; 167 #ifdef xTRACE 168 if (Trace) 169 printf("New quad: ix = %d, iy = %d\n", ix, iy); 170 #endif 171 Ship.sectx = x; 172 Ship.secty = y; 173 compkldist(0); 174 Move.newquad = 2; 175 attack(0); 176 checkcond(); 177 Ship.quadx = ix / NSECTS; 178 Ship.quady = iy / NSECTS; 179 Ship.sectx = ix % NSECTS; 180 Ship.secty = iy % NSECTS; 181 if (ix < 0 || Ship.quadx >= NQUADS || iy < 0 || 182 Ship.quady >= NQUADS) { 183 if (!damaged(COMPUTER)) { 184 dumpme(0); 185 } else 186 lose(L_NEGENB); 187 } 188 initquad(0); 189 n = 0; 190 break; 191 } 192 if (Sect[ix][iy] != EMPTY) { 193 /* we just hit something */ 194 if (!damaged(COMPUTER) && ramflag <= 0) { 195 ix = x - dx; 196 iy = y - dy; 197 printf("Computer reports navigation error; " 198 "%s stopped at %d,%d\n", 199 Ship.shipname, ix, iy); 200 Ship.energy -= Param.stopengy * speed; 201 break; 202 } 203 /* test for a black hole */ 204 if (Sect[ix][iy] == HOLE) { 205 /* get dumped elsewhere in the galaxy */ 206 dumpme(1); 207 initquad(0); 208 n = 0; 209 break; 210 } 211 ram(ix, iy); 212 break; 213 } 214 } 215 if (n > 0) { 216 dx = Ship.sectx - ix; 217 dy = Ship.secty - iy; 218 dist = sqrt(dx * dx + dy * dy) / NSECTS; 219 time = dist / speed; 220 if (evtime > time) { 221 /* spring the LRTB trap */ 222 time = evtime; 223 } 224 Ship.sectx = ix; 225 Ship.secty = iy; 226 } 227 Sect[Ship.sectx][Ship.secty] = Ship.ship; 228 compkldist(0); 229 return (time); 230 } 231