![[BACK]](/cvsweb/icons/back.gif){kind=icon}
Return to move.c CVS log ![[TXT]](/cvsweb/icons/text.gif){kind=icon}
![[DIR]](/cvsweb/icons/dir.gif){kind=icon}
Up to [CSRG BSD Unix] / 42BSD / games / trek|
Return to move.c CVS log | Up to [CSRG BSD Unix] / 42BSD / games / trek |
1.1 root 1: #ifndef lint
2: static char sccsid[] = "@(#)move.c 4.3 (Berkeley) 5/27/83";
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: }
This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.