1 /*-
2 * Copyright (c) 1990, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Ed James.
7 *
8 * %sccs.include.redist.c%
9 */
10
11 /*
12 * Copyright (c) 1987 by Ed James, UC Berkeley. All rights reserved.
13 *
14 * Copy permission is hereby granted provided that this notice is
15 * retained on all partial or complete copies.
16 *
17 * For more info on this and all of my stuff, mail edjames@berkeley.edu.
18 */
19
20 #ifndef lint
21 static char sccsid[] = "@(#)update.c 8.1 (Berkeley) 05/31/93";
22 #endif not lint
23
24 #include "include.h"
25
update()26 update()
27 {
28 int i, dir_diff, mask, unclean;
29 PLANE *pp, *p1, *p2, *p;
30
31 #ifdef BSD
32 mask = sigblock(sigmask(SIGINT));
33 #endif
34 #ifdef SYSV
35 alarm(0);
36 signal(SIGALRM, update);
37 #endif
38
39 clck++;
40
41 erase_all();
42
43 /* put some planes in the air */
44 do {
45 unclean = 0;
46 for (pp = ground.head; pp != NULL; pp = pp->next) {
47 if (pp->new_altitude > 0) {
48 delete(&ground, pp);
49 append(&air, pp);
50 unclean = 1;
51 break;
52 }
53 }
54 } while (unclean);
55
56 /* do altitude change and basic movement */
57 for (pp = air.head; pp != NULL; pp = pp->next) {
58 /* type 0 only move every other turn */
59 if (pp->plane_type == 0 && clck & 1)
60 continue;
61
62 pp->fuel--;
63 if (pp->fuel < 0)
64 loser(pp, "ran out of fuel.");
65
66 pp->altitude += SGN(pp->new_altitude - pp->altitude);
67
68 if (!pp->delayd) {
69 dir_diff = pp->new_dir - pp->dir;
70 /*
71 * Allow for circle commands
72 */
73 if (pp->new_dir >= 0 && pp->new_dir < MAXDIR) {
74 if (dir_diff > MAXDIR/2)
75 dir_diff -= MAXDIR;
76 else if (dir_diff < -(MAXDIR/2))
77 dir_diff += MAXDIR;
78 }
79 if (dir_diff > 2)
80 dir_diff = 2;
81 else if (dir_diff < -2)
82 dir_diff = -2;
83 pp->dir += dir_diff;
84 if (pp->dir >= MAXDIR)
85 pp->dir -= MAXDIR;
86 else if (pp->dir < 0)
87 pp->dir += MAXDIR;
88 }
89 pp->xpos += displacement[pp->dir].dx;
90 pp->ypos += displacement[pp->dir].dy;
91
92 if (pp->delayd && pp->xpos == sp->beacon[pp->delayd_no].x &&
93 pp->ypos == sp->beacon[pp->delayd_no].y) {
94 pp->delayd = 0;
95 if (pp->status == S_UNMARKED)
96 pp->status = S_MARKED;
97 }
98
99 switch (pp->dest_type) {
100 case T_AIRPORT:
101 if (pp->xpos == sp->airport[pp->dest_no].x &&
102 pp->ypos == sp->airport[pp->dest_no].y &&
103 pp->altitude == 0) {
104 if (pp->dir != sp->airport[pp->dest_no].dir)
105 loser(pp, "landed in the wrong direction.");
106 else {
107 pp->status = S_GONE;
108 continue;
109 }
110 }
111 break;
112 case T_EXIT:
113 if (pp->xpos == sp->exit[pp->dest_no].x &&
114 pp->ypos == sp->exit[pp->dest_no].y) {
115 if (pp->altitude != 9)
116 loser(pp, "exited at the wrong altitude.");
117 else {
118 pp->status = S_GONE;
119 continue;
120 }
121 }
122 break;
123 default:
124 loser(pp, "has a bizarre destination, get help!");
125 }
126 if (pp->altitude > 9)
127 /* "this is impossible" */
128 loser(pp, "exceded flight ceiling.");
129 if (pp->altitude <= 0) {
130 for (i = 0; i < sp->num_airports; i++)
131 if (pp->xpos == sp->airport[i].x &&
132 pp->ypos == sp->airport[i].y) {
133 if (pp->dest_type == T_AIRPORT)
134 loser(pp,
135 "landed at the wrong airport.");
136 else
137 loser(pp,
138 "landed instead of exited.");
139 }
140 loser(pp, "crashed on the ground.");
141 }
142 if (pp->xpos < 1 || pp->xpos >= sp->width - 1 ||
143 pp->ypos < 1 || pp->ypos >= sp->height - 1) {
144 for (i = 0; i < sp->num_exits; i++)
145 if (pp->xpos == sp->exit[i].x &&
146 pp->ypos == sp->exit[i].y) {
147 if (pp->dest_type == T_EXIT)
148 loser(pp,
149 "exited via the wrong exit.");
150 else
151 loser(pp,
152 "exited instead of landed.");
153 }
154 loser(pp, "illegally left the flight arena.");
155 }
156 }
157
158 /*
159 * Traverse the list once, deleting the planes that are gone.
160 */
161 for (pp = air.head; pp != NULL; pp = p2) {
162 p2 = pp->next;
163 if (pp->status == S_GONE) {
164 safe_planes++;
165 delete(&air, pp);
166 }
167 }
168
169 draw_all();
170
171 for (p1 = air.head; p1 != NULL; p1 = p1->next)
172 for (p2 = p1->next; p2 != NULL; p2 = p2->next)
173 if (too_close(p1, p2, 1)) {
174 static char buf[80];
175
176 (void)sprintf(buf, "collided with plane '%c'.",
177 name(p2));
178 loser(p1, buf);
179 }
180 /*
181 * Check every other update. Actually, only add on even updates.
182 * Otherwise, prop jobs show up *on* entrance. Remember that
183 * we don't update props on odd updates.
184 */
185 if ((rand() % sp->newplane_time) == 0)
186 addplane();
187
188 #ifdef BSD
189 sigsetmask(mask);
190 #endif
191 #ifdef SYSV
192 alarm(sp->update_secs);
193 #endif
194 }
195
196 char *
command(pp)197 command(pp)
198 PLANE *pp;
199 {
200 static char buf[50], *bp, *comm_start;
201 char *index();
202
203 buf[0] = '\0';
204 bp = buf;
205 (void)sprintf(bp, "%c%d%c%c%d: ", name(pp), pp->altitude,
206 (pp->fuel < LOWFUEL) ? '*' : ' ',
207 (pp->dest_type == T_AIRPORT) ? 'A' : 'E', pp->dest_no);
208
209 comm_start = bp = index(buf, '\0');
210 if (pp->altitude == 0)
211 (void)sprintf(bp, "Holding @ A%d", pp->orig_no);
212 else if (pp->new_dir >= MAXDIR || pp->new_dir < 0)
213 strcpy(bp, "Circle");
214 else if (pp->new_dir != pp->dir)
215 (void)sprintf(bp, "%d", dir_deg(pp->new_dir));
216
217 bp = index(buf, '\0');
218 if (pp->delayd)
219 (void)sprintf(bp, " @ B%d", pp->delayd_no);
220
221 bp = index(buf, '\0');
222 if (*comm_start == '\0' &&
223 (pp->status == S_UNMARKED || pp->status == S_IGNORED))
224 strcpy(bp, "---------");
225 return (buf);
226 }
227
228 /* char */
name(p)229 name(p)
230 PLANE *p;
231 {
232 if (p->plane_type == 0)
233 return ('A' + p->plane_no);
234 else
235 return ('a' + p->plane_no);
236 }
237
number(l)238 number(l)
239 {
240 if (l < 'a' && l > 'z' && l < 'A' && l > 'Z')
241 return (-1);
242 else if (l >= 'a' && l <= 'z')
243 return (l - 'a');
244 else
245 return (l - 'A');
246 }
247
next_plane()248 next_plane()
249 {
250 static int last_plane = -1;
251 PLANE *pp;
252 int found, start_plane = last_plane;
253
254 do {
255 found = 0;
256 last_plane++;
257 if (last_plane >= 26)
258 last_plane = 0;
259 for (pp = air.head; pp != NULL; pp = pp->next)
260 if (pp->plane_no == last_plane) {
261 found++;
262 break;
263 }
264 if (!found)
265 for (pp = ground.head; pp != NULL; pp = pp->next)
266 if (pp->plane_no == last_plane) {
267 found++;
268 break;
269 }
270 } while (found && last_plane != start_plane);
271 if (last_plane == start_plane)
272 return (-1);
273 return (last_plane);
274 }
275
addplane()276 addplane()
277 {
278 PLANE p, *pp, *p1;
279 int i, num_starts, close, rnd, rnd2, pnum;
280
281 bzero(&p, sizeof (p));
282
283 p.status = S_MARKED;
284 p.plane_type = random() % 2;
285
286 num_starts = sp->num_exits + sp->num_airports;
287 rnd = random() % num_starts;
288
289 if (rnd < sp->num_exits) {
290 p.dest_type = T_EXIT;
291 p.dest_no = rnd;
292 } else {
293 p.dest_type = T_AIRPORT;
294 p.dest_no = rnd - sp->num_exits;
295 }
296
297 /* loop until we get a plane not near another */
298 for (i = 0; i < num_starts; i++) {
299 /* loop till we get a different start point */
300 while ((rnd2 = random() % num_starts) == rnd)
301 ;
302 if (rnd2 < sp->num_exits) {
303 p.orig_type = T_EXIT;
304 p.orig_no = rnd2;
305 p.xpos = sp->exit[rnd2].x;
306 p.ypos = sp->exit[rnd2].y;
307 p.new_dir = p.dir = sp->exit[rnd2].dir;
308 p.altitude = p.new_altitude = 7;
309 close = 0;
310 for (p1 = air.head; p1 != NULL; p1 = p1->next)
311 if (too_close(p1, &p, 4)) {
312 close++;
313 break;
314 }
315 if (close)
316 continue;
317 } else {
318 p.orig_type = T_AIRPORT;
319 p.orig_no = rnd2 - sp->num_exits;
320 p.xpos = sp->airport[p.orig_no].x;
321 p.ypos = sp->airport[p.orig_no].y;
322 p.new_dir = p.dir = sp->airport[p.orig_no].dir;
323 p.altitude = p.new_altitude = 0;
324 }
325 p.fuel = sp->width + sp->height;
326 break;
327 }
328 if (i >= num_starts)
329 return (-1);
330 pnum = next_plane();
331 if (pnum < 0)
332 return (-1);
333 p.plane_no = pnum;
334
335 pp = newplane();
336 bcopy(&p, pp, sizeof (p));
337
338 if (pp->orig_type == T_AIRPORT)
339 append(&ground, pp);
340 else
341 append(&air, pp);
342
343 return (pp->dest_type);
344 }
345
346 PLANE *
findplane(n)347 findplane(n)
348 {
349 PLANE *pp;
350
351 for (pp = air.head; pp != NULL; pp = pp->next)
352 if (pp->plane_no == n)
353 return (pp);
354 for (pp = ground.head; pp != NULL; pp = pp->next)
355 if (pp->plane_no == n)
356 return (pp);
357 return (NULL);
358 }
359
too_close(p1,p2,dist)360 too_close(p1, p2, dist)
361 PLANE *p1, *p2;
362 {
363 if (ABS(p1->altitude - p2->altitude) <= dist &&
364 ABS(p1->xpos - p2->xpos) <= dist && ABS(p1->ypos - p2->ypos) <= dist)
365 return (1);
366 else
367 return (0);
368 }
369
dir_deg(d)370 dir_deg(d)
371 {
372 switch (d) {
373 case 0: return (0);
374 case 1: return (45);
375 case 2: return (90);
376 case 3: return (135);
377 case 4: return (180);
378 case 5: return (225);
379 case 6: return (270);
380 case 7: return (315);
381 default:
382 return (-1);
383 }
384 }
385