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. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)move.c 8.1 (Berkeley) 5/31/93 34 * $FreeBSD: src/games/trek/move.c,v 1.6 1999/11/30 03:49:50 billf Exp $ 35 * $DragonFly: src/games/trek/move.c,v 1.3 2006/09/07 21:19:44 pavalos Exp $ 36 */ 37 38 # include "trek.h" 39 40 /* 41 ** Move Under Warp or Impulse Power 42 ** 43 ** `Ramflag' is set if we are to be allowed to ram stars, 44 ** Klingons, etc. This is passed from warp(), which gets it from 45 ** either play() or ram(). Course is the course (0 -> 360) at 46 ** which we want to move. `Speed' is the speed we 47 ** want to go, and `p_time' is the expected time. It 48 ** can get cut short if a long range tractor beam is to occur. We 49 ** cut short the move so that the user doesn't get docked time and 50 ** energy for distance which he didn't travel. 51 ** 52 ** We check the course through the current quadrant to see that he 53 ** doesn't run into anything. After that, though, space sort of 54 ** bends around him. Note that this puts us in the awkward posi- 55 ** tion of being able to be dropped into a sector which is com- 56 ** pletely surrounded by stars. Oh Well. 57 ** 58 ** If the SINS (Space Inertial Navigation System) is out, we ran- 59 ** domize the course accordingly before ever starting to move. 60 ** We will still move in a straight line. 61 ** 62 ** Note that if your computer is out, you ram things anyway. In 63 ** other words, if your computer and sins are both out, you're in 64 ** potentially very bad shape. 65 ** 66 ** Klingons get a chance to zap you as you leave the quadrant. 67 ** By the way, they also try to follow you (heh heh). 68 ** 69 ** Return value is the actual amount of time used. 70 ** 71 ** 72 ** Uses trace flag 4. 73 */ 74 75 double 76 move(int ramflag, int course, double p_time, double speed) 77 { 78 double angle; 79 double x, y, dx, dy; 80 int ix, iy; 81 double bigger; 82 int n; 83 int i; 84 double dist; 85 double sectsize; 86 double xn; 87 double evtime; 88 89 ix = iy = 0; 90 # ifdef xTRACE 91 if (Trace) 92 printf("move: ramflag %d course %d time %.2f speed %.2f\n", 93 ramflag, course, p_time, speed); 94 # endif 95 sectsize = NSECTS; 96 /* initialize delta factors for move */ 97 angle = course * 0.0174532925; 98 if (damaged(SINS)) 99 angle += Param.navigcrud[1] * (franf() - 0.5); 100 else 101 if (Ship.sinsbad) 102 angle += Param.navigcrud[0] * (franf() - 0.5); 103 dx = -cos(angle); 104 dy = sin(angle); 105 bigger = fabs(dx); 106 dist = fabs(dy); 107 if (dist > bigger) 108 bigger = dist; 109 dx /= bigger; 110 dy /= bigger; 111 112 /* check for long range tractor beams */ 113 /**** TEMPORARY CODE == DEBUGGING ****/ 114 evtime = Now.eventptr[E_LRTB]->date - Now.date; 115 # ifdef xTRACE 116 if (Trace) 117 printf("E.ep = %p, ->evcode = %d, ->date = %.2f, evtime = %.2f\n", 118 (void *)Now.eventptr[E_LRTB], 119 Now.eventptr[E_LRTB]->evcode, 120 Now.eventptr[E_LRTB]->date, evtime); 121 # endif 122 if (p_time > evtime && Etc.nkling < 3) 123 { 124 /* then we got a LRTB */ 125 evtime += 0.005; 126 p_time = evtime; 127 } 128 else 129 evtime = -1.0e50; 130 dist = p_time * speed; 131 132 /* move within quadrant */ 133 Sect[Ship.sectx][Ship.secty] = EMPTY; 134 x = Ship.sectx + 0.5; 135 y = Ship.secty + 0.5; 136 xn = NSECTS * dist * bigger; 137 n = xn + 0.5; 138 # ifdef xTRACE 139 if (Trace) 140 printf("dx = %.2f, dy = %.2f, xn = %.2f, n = %d\n", dx, dy, xn, n); 141 # endif 142 Move.free = 0; 143 144 for (i = 0; i < n; i++) 145 { 146 ix = (x += dx); 147 iy = (y += dy); 148 # ifdef xTRACE 149 if (Trace) 150 printf("ix = %d, x = %.2f, iy = %d, y = %.2f\n", ix, x, iy, y); 151 # endif 152 if (x < 0.0 || y < 0.0 || x >= sectsize || y >= sectsize) 153 { 154 /* enter new quadrant */ 155 dx = Ship.quadx * NSECTS + Ship.sectx + dx * xn; 156 dy = Ship.quady * NSECTS + Ship.secty + dy * xn; 157 if (dx < 0.0) 158 ix = -1; 159 else 160 ix = dx + 0.5; 161 if (dy < 0.0) 162 iy = -1; 163 else 164 iy = dy + 0.5; 165 # ifdef xTRACE 166 if (Trace) 167 printf("New quad: ix = %d, iy = %d\n", ix, iy); 168 # endif 169 Ship.sectx = x; 170 Ship.secty = y; 171 compkldist(0); 172 Move.newquad = 2; 173 attack(0); 174 checkcond(); 175 Ship.quadx = ix / NSECTS; 176 Ship.quady = iy / NSECTS; 177 Ship.sectx = ix % NSECTS; 178 Ship.secty = iy % NSECTS; 179 if (ix < 0 || Ship.quadx >= NQUADS || iy < 0 || Ship.quady >= NQUADS) 180 { 181 if (!damaged(COMPUTER)) 182 { 183 dumpme(0); 184 } 185 else 186 lose(L_NEGENB); 187 } 188 initquad(0); 189 n = 0; 190 break; 191 } 192 if (Sect[ix][iy] != EMPTY) 193 { 194 /* we just hit something */ 195 if (!damaged(COMPUTER) && ramflag <= 0) 196 { 197 ix = x - dx; 198 iy = y - dy; 199 printf("Computer reports navigation error; %s stopped at %d,%d\n", 200 Ship.shipname, ix, iy); 201 Ship.energy -= Param.stopengy * speed; 202 break; 203 } 204 /* test for a black hole */ 205 if (Sect[ix][iy] == HOLE) 206 { 207 /* get dumped elsewhere in the galaxy */ 208 dumpme(1); 209 initquad(0); 210 n = 0; 211 break; 212 } 213 ram(ix, iy); 214 break; 215 } 216 } 217 if (n > 0) 218 { 219 dx = Ship.sectx - ix; 220 dy = Ship.secty - iy; 221 dist = sqrt(dx * dx + dy * dy) / NSECTS; 222 p_time = dist / speed; 223 if (evtime > p_time) 224 p_time = evtime; /* spring the LRTB trap */ 225 Ship.sectx = ix; 226 Ship.secty = iy; 227 } 228 Sect[Ship.sectx][Ship.secty] = Ship.ship; 229 compkldist(0); 230 return (p_time); 231 } 232