1 #ifndef lint 2 static char sccsid[] = "@(#)move.c 4.3 (Berkeley) 05/27/83"; 3 #endif not lint 4 5 # include "trek.h" 6 7 /* 8 ** Move Under Warp or Impulse Power 9 ** 10 ** `Ramflag' is set if we are to be allowed to ram stars, 11 ** Klingons, etc. This is passed from warp(), which gets it from 12 ** either play() or ram(). Course is the course (0 -> 360) at 13 ** which we want to move. `Speed' is the speed we 14 ** want to go, and `time' is the expected time. It 15 ** can get cut short if a long range tractor beam is to occur. We 16 ** cut short the move so that the user doesn't get docked time and 17 ** energy for distance which he didn't travel. 18 ** 19 ** We check the course through the current quadrant to see that he 20 ** doesn't run into anything. After that, though, space sort of 21 ** bends around him. Note that this puts us in the awkward posi- 22 ** tion of being able to be dropped into a sector which is com- 23 ** pletely surrounded by stars. Oh Well. 24 ** 25 ** If the SINS (Space Inertial Navigation System) is out, we ran- 26 ** domize the course accordingly before ever starting to move. 27 ** We will still move in a straight line. 28 ** 29 ** Note that if your computer is out, you ram things anyway. In 30 ** other words, if your computer and sins are both out, you're in 31 ** potentially very bad shape. 32 ** 33 ** Klingons get a chance to zap you as you leave the quadrant. 34 ** By the way, they also try to follow you (heh heh). 35 ** 36 ** Return value is the actual amount of time used. 37 ** 38 ** 39 ** Uses trace flag 4. 40 */ 41 42 double move(ramflag, course, time, speed) 43 int ramflag; 44 int course; 45 double time; 46 double speed; 47 { 48 double angle; 49 double x, y, dx, dy; 50 register int ix, iy; 51 double bigger; 52 int n; 53 register int i; 54 double dist; 55 double sectsize; 56 double xn; 57 double evtime; 58 59 # ifdef xTRACE 60 if (Trace) 61 printf("move: ramflag %d course %d time %.2f speed %.2f\n", 62 ramflag, course, time, speed); 63 # endif 64 sectsize = NSECTS; 65 /* initialize delta factors for move */ 66 angle = course * 0.0174532925; 67 if (damaged(SINS)) 68 angle += Param.navigcrud[1] * (franf() - 0.5); 69 else 70 if (Ship.sinsbad) 71 angle += Param.navigcrud[0] * (franf() - 0.5); 72 dx = -cos(angle); 73 dy = sin(angle); 74 bigger = fabs(dx); 75 dist = fabs(dy); 76 if (dist > bigger) 77 bigger = dist; 78 dx /= bigger; 79 dy /= bigger; 80 81 /* check for long range tractor beams */ 82 /**** TEMPORARY CODE == DEBUGGING ****/ 83 evtime = Now.eventptr[E_LRTB]->date - Now.date; 84 # ifdef xTRACE 85 if (Trace) 86 printf("E.ep = %u, ->evcode = %d, ->date = %.2f, evtime = %.2f\n", 87 Now.eventptr[E_LRTB], Now.eventptr[E_LRTB]->evcode, 88 Now.eventptr[E_LRTB]->date, evtime); 89 # endif 90 if (time > evtime && Etc.nkling < 3) 91 { 92 /* then we got a LRTB */ 93 evtime += 0.005; 94 time = evtime; 95 } 96 else 97 evtime = -1.0e50; 98 dist = time * speed; 99 100 /* move within quadrant */ 101 Sect[Ship.sectx][Ship.secty] = EMPTY; 102 x = Ship.sectx + 0.5; 103 y = Ship.secty + 0.5; 104 xn = NSECTS * dist * bigger; 105 n = xn + 0.5; 106 # ifdef xTRACE 107 if (Trace) 108 printf("dx = %.2f, dy = %.2f, xn = %.2f, n = %d\n", dx, dy, xn, n); 109 # endif 110 Move.free = 0; 111 112 for (i = 0; i < n; i++) 113 { 114 ix = (x += dx); 115 iy = (y += dy); 116 # ifdef xTRACE 117 if (Trace) 118 printf("ix = %d, x = %.2f, iy = %d, y = %.2f\n", ix, x, iy, y); 119 # endif 120 if (x < 0.0 || y < 0.0 || x >= sectsize || y >= sectsize) 121 { 122 /* enter new quadrant */ 123 dx = Ship.quadx * NSECTS + Ship.sectx + dx * xn; 124 dy = Ship.quady * NSECTS + Ship.secty + dy * xn; 125 if (dx < 0.0) 126 ix = -1; 127 else 128 ix = dx + 0.5; 129 if (dy < 0.0) 130 iy = -1; 131 else 132 iy = dy + 0.5; 133 # ifdef xTRACE 134 if (Trace) 135 printf("New quad: ix = %d, iy = %d\n", ix, iy); 136 # endif 137 Ship.sectx = x; 138 Ship.secty = y; 139 compkldist(0); 140 Move.newquad = 2; 141 attack(0); 142 checkcond(); 143 Ship.quadx = ix / NSECTS; 144 Ship.quady = iy / NSECTS; 145 Ship.sectx = ix % NSECTS; 146 Ship.secty = iy % NSECTS; 147 if (ix < 0 || Ship.quadx >= NQUADS || iy < 0 || Ship.quady >= NQUADS) 148 if (!damaged(COMPUTER)) 149 { 150 dumpme(0); 151 } 152 else 153 lose(L_NEGENB); 154 initquad(0); 155 n = 0; 156 break; 157 } 158 if (Sect[ix][iy] != EMPTY) 159 { 160 /* we just hit something */ 161 if (!damaged(COMPUTER) && ramflag <= 0) 162 { 163 ix = x - dx; 164 iy = y - dy; 165 printf("Computer reports navigation error; %s stopped at %d,%d\n", 166 Ship.shipname, ix, iy); 167 Ship.energy -= Param.stopengy * speed; 168 break; 169 } 170 /* test for a black hole */ 171 if (Sect[ix][iy] == HOLE) 172 { 173 /* get dumped elsewhere in the galaxy */ 174 dumpme(1); 175 initquad(0); 176 n = 0; 177 break; 178 } 179 ram(ix, iy); 180 break; 181 } 182 } 183 if (n > 0) 184 { 185 dx = Ship.sectx - ix; 186 dy = Ship.secty - iy; 187 dist = sqrt(dx * dx + dy * dy) / NSECTS; 188 time = dist / speed; 189 if (evtime > time) 190 time = evtime; /* spring the LRTB trap */ 191 Ship.sectx = ix; 192 Ship.secty = iy; 193 } 194 Sect[Ship.sectx][Ship.secty] = Ship.ship; 195 compkldist(0); 196 return (time); 197 } 198