1 /* -*- Mode: C; tab-width: 4 -*- */
2 /* galaxy --- spinning galaxies */
5 static const char sccsid[] = "@(#)galaxy.c 4.04 97/07/28 xlockmore";
8 /* Originally done by Uli Siegmund <uli@wombat.okapi.sub.org> on Amiga
10 * Port from Cluster/EGS to C/Intuition by Harald Backert
11 * Port to X11 and incorporation into xlockmore by Hubert Feyrer
12 * <hubert.feyrer@rz.uni-regensburg.de>
14 * Permission to use, copy, modify, and distribute this software and its
15 * documentation for any purpose and without fee is hereby granted,
16 * provided that the above copyright notice appear in all copies and that
17 * both that copyright notice and this permission notice appear in
18 * supporting documentation.
20 * This file is provided AS IS with no warranties of any kind. The author
21 * shall have no liability with respect to the infringement of copyrights,
22 * trade secrets or any patents by this file or any part thereof. In no
23 * event will the author be liable for any lost revenue or profits or
24 * other special, indirect and consequential damages.
27 * 26-Aug-00: robert.nagtegaal@phil.uu.nl and roland@tschai.demon.nl:
28 * various improvements
29 * 10-May-97: jwz@jwz.org: turned into a standalone program.
30 * 18-Apr-97: Memory leak fixed by Tom Schmidt <tschmidt@micron.com>
31 * 07-Apr-97: Modified by Dave Mitchell <davem@magnet.com>
32 * 23-Oct-94: Modified by David Bagley <bagleyd@bigfoot.com>
34 * colors change depending on velocity
35 * 10-Oct-94: Add colors by Hubert Feyer
36 * 30-Sep-94: Initial port by Hubert Feyer
37 * 09-Mar-94: VMS can generate a random number 0.0 which results in a
38 * division by zero, corrected by Jouk Jansen
39 * <joukj@crys.chem.uva.nl>
43 # define DEFAULTS "*delay: 20000 \n" \
47 # define UNIFORM_COLORS
48 # define reshape_galaxy 0
49 # define galaxy_handle_event 0
50 # include "xlockmore.h" /* from the xscreensaver distribution */
51 #else /* !STANDALONE */
52 # include "xlock.h" /* from the xlockmore distribution */
53 #endif /* !STANDALONE */
59 #define DEF_TRACKS "True"
60 #define DEF_SPIN "True"
61 #define DEF_DBUF "True"
63 static XrmOptionDescRec opts[] =
65 {"-tracks", ".galaxy.tracks", XrmoptionNoArg, "on"},
66 {"+tracks", ".galaxy.tracks", XrmoptionNoArg, "off"},
67 {"-spin", ".galaxy.spin", XrmoptionNoArg, "on"},
68 {"+spin", ".galaxy.spin", XrmoptionNoArg, "off"},
69 {"-dbuf", ".galaxy.dbuf", XrmoptionNoArg, "on"},
70 {"+dbuf", ".galaxy.dbuf", XrmoptionNoArg, "off"},
73 static argtype vars[] =
75 {&tracks, "tracks", "Tracks", DEF_TRACKS, t_Bool},
76 {&spin, "spin", "Spin", DEF_SPIN, t_Bool},
77 {&dbufp, "dbuf", "Dbuf", DEF_DBUF, t_Bool},
80 static OptionStruct desc[] =
82 {"-/+tracks", "turn on/off star tracks"},
83 {"-/+spin", "do/don't spin viewpoint"},
84 {"-/+dbuf", "turn on/off double buffering."},
87 ENTRYPOINT ModeSpecOpt galaxy_opts =
88 {sizeof opts / sizeof opts[0], opts,
89 sizeof vars / sizeof vars[0], vars, desc};
92 #define FLOATRAND ((double) LRAND() / ((double) MAXRAND))
95 #define WRAP 1 /* Warp around edges */
96 #define BOUNCE 1 /* Bounce from borders */
100 #define MINGALAXIES 2
101 #define MAX_STARS 3000
102 #define MAX_IDELTAT 50
103 /* These come originally from the Cluster-version */
104 #define DEFAULT_GALAXIES 3
105 #define DEFAULT_STARS 1000
106 #define DEFAULT_HITITERATIONS 7500
107 #define DEFAULT_IDELTAT 200 /* 0.02 */
108 #define EPSILON 0.00000001
110 #define sqrt_EPSILON 0.0001
112 #define DELTAT (MAX_IDELTAT * 0.0001)
114 #define GALAXYRANGESIZE 0.1
115 #define GALAXYMINSIZE 0.15
120 /* colors per galaxy */
121 /* #define COLORSTEP (NUMCOLORS/COLORBASE) */
122 # define COLORSTEP (MI_NCOLORS(mi)/COLORBASE)
126 double pos[3], vel[3];
136 double pos[3], vel[3];
141 double mat[3][3]; /* Movement of stars(?) */
142 double scale; /* Scale */
143 int midx; /* Middle of screen, x */
144 int midy; /* Middle of screen, y */
146 double diff[3]; /* */
147 Galaxy *galaxies; /* the Whole Universe */
148 int ngalaxies; /* # galaxies */
149 int f_hititerations; /* # iterations before restart */
151 double rot_y; /* rotation of eye around center of universe, around
153 double rot_x; /* rotation of eye around center of universe, around
157 static unistruct *universes = NULL;
160 free_galaxies(unistruct * gp)
162 if (gp->galaxies != NULL) {
165 for (i = 0; i < gp->ngalaxies; i++) {
166 Galaxy *gt = &gp->galaxies[i];
168 if (gt->stars != NULL)
169 (void) free((void *) gt->stars);
170 if (gt->oldpoints != NULL)
171 (void) free((void *) gt->oldpoints);
172 if (gt->newpoints != NULL)
173 (void) free((void *) gt->newpoints);
175 (void) free((void *) gp->galaxies);
181 startover(ModeInfo * mi)
183 unistruct *gp = &universes[MI_SCREEN(mi)];
184 int i, j; /* more tmp */
185 double w1, w2; /* more tmp */
186 double d, v, w, h; /* yet more tmp */
192 if (MI_BATCHCOUNT(mi) < -MINGALAXIES)
194 gp->ngalaxies = MI_BATCHCOUNT(mi);
195 if (gp->ngalaxies < -MINGALAXIES)
196 gp->ngalaxies = NRAND(-gp->ngalaxies - MINGALAXIES + 1) + MINGALAXIES;
198 else if (gp->ngalaxies < MINGALAXIES)
199 gp->ngalaxies = MINGALAXIES;
200 if (gp->galaxies == NULL)
201 gp->galaxies = (Galaxy *) calloc(gp->ngalaxies, sizeof (Galaxy));
203 for (i = 0; i < gp->ngalaxies; ++i) {
204 Galaxy *gt = &gp->galaxies[i];
205 double sinw1, sinw2, cosw1, cosw2;
207 gt->galcol = NRAND(COLORBASE - 2);
209 gt->galcol += 2; /* Mult 8; 16..31 no green stars */
210 /* Galaxies still may have some green stars but are not all green. */
212 if (gt->stars != NULL) {
213 (void) free((void *) gt->stars);
216 gt->nstars = (NRAND(MAX_STARS / 2)) + MAX_STARS / 2;
217 gt->stars = (Star *) malloc(gt->nstars * sizeof (Star));
218 gt->oldpoints = (XPoint *) malloc(gt->nstars * sizeof (XPoint));
219 gt->newpoints = (XPoint *) malloc(gt->nstars * sizeof (XPoint));
221 w1 = 2.0 * M_PI * FLOATRAND;
222 w2 = 2.0 * M_PI * FLOATRAND;
228 gp->mat[0][0] = cosw2;
229 gp->mat[0][1] = -sinw1 * sinw2;
230 gp->mat[0][2] = cosw1 * sinw2;
232 gp->mat[1][1] = cosw1;
233 gp->mat[1][2] = sinw1;
234 gp->mat[2][0] = -sinw2;
235 gp->mat[2][1] = -sinw1 * cosw2;
236 gp->mat[2][2] = cosw1 * cosw2;
238 gt->vel[0] = FLOATRAND * 2.0 - 1.0;
239 gt->vel[1] = FLOATRAND * 2.0 - 1.0;
240 gt->vel[2] = FLOATRAND * 2.0 - 1.0;
241 gt->pos[0] = -gt->vel[0] * DELTAT * gp->f_hititerations + FLOATRAND -
243 gt->pos[1] = -gt->vel[1] * DELTAT * gp->f_hititerations + FLOATRAND -
245 gt->pos[2] = -gt->vel[2] * DELTAT * gp->f_hititerations + FLOATRAND -
248 gt->mass = (int) (FLOATRAND * 1000.0) + 1;
250 gp->size = GALAXYRANGESIZE * FLOATRAND + GALAXYMINSIZE;
252 for (j = 0; j < gt->nstars; ++j) {
253 Star *st = >->stars[j];
254 XPoint *oldp = >->oldpoints[j];
255 XPoint *newp = >->newpoints[j];
259 w = 2.0 * M_PI * FLOATRAND;
262 d = FLOATRAND * gp->size;
263 h = FLOATRAND * exp(-2.0 * (d / gp->size)) / 5.0 * gp->size;
266 st->pos[0] = gp->mat[0][0] * d * cosw + gp->mat[1][0] * d * sinw +
267 gp->mat[2][0] * h + gt->pos[0];
268 st->pos[1] = gp->mat[0][1] * d * cosw + gp->mat[1][1] * d * sinw +
269 gp->mat[2][1] * h + gt->pos[1];
270 st->pos[2] = gp->mat[0][2] * d * cosw + gp->mat[1][2] * d * sinw +
271 gp->mat[2][2] * h + gt->pos[2];
273 v = sqrt(gt->mass * QCONS / sqrt(d * d + h * h));
274 st->vel[0] = -gp->mat[0][0] * v * sinw + gp->mat[1][0] * v * cosw +
276 st->vel[1] = -gp->mat[0][1] * v * sinw + gp->mat[1][1] * v * cosw +
278 st->vel[2] = -gp->mat[0][2] * v * sinw + gp->mat[1][2] * v * cosw +
281 st->vel[0] *= DELTAT;
282 st->vel[1] *= DELTAT;
283 st->vel[2] *= DELTAT;
293 XClearWindow(MI_DISPLAY(mi), MI_WINDOW(mi));
296 (void) printf("ngalaxies=%d, f_hititerations=%d\n", gp->ngalaxies,
297 gp->f_hititerations);
298 (void) printf("f_deltat=%g\n", DELTAT);
299 (void) printf("Screen: ");
304 init_galaxy(ModeInfo * mi)
308 if (universes == NULL) {
309 if ((universes = (unistruct *) calloc(MI_NUM_SCREENS(mi),
310 sizeof (unistruct))) == NULL)
313 gp = &universes[MI_SCREEN(mi)];
315 # ifdef HAVE_COCOA /* Don't second-guess Quartz's double-buffering */
319 gp->f_hititerations = MI_CYCLES(mi);
321 gp->scale = (double) (MI_WIN_WIDTH(mi) + MI_WIN_HEIGHT(mi)) / 8.0;
322 gp->midx = MI_WIN_WIDTH(mi) / 2;
323 gp->midy = MI_WIN_HEIGHT(mi) / 2;
328 draw_galaxy(ModeInfo * mi)
330 Display *display = MI_DISPLAY(mi);
331 Window window = MI_WINDOW(mi);
333 unistruct *gp = &universes[MI_SCREEN(mi)];
334 double d, eps, cox, six, cor, sir; /* tmp */
335 int i, j, k; /* more tmp */
336 XPoint *dummy = NULL;
339 XClearWindow(MI_DISPLAY(mi), MI_WINDOW(mi));
346 cox = COSF(gp->rot_y);
347 six = SINF(gp->rot_y);
348 cor = COSF(gp->rot_x);
349 sir = SINF(gp->rot_x);
351 eps = 1/(EPSILON * sqrt_EPSILON * DELTAT * DELTAT * QCONS);
353 for (i = 0; i < gp->ngalaxies; ++i) {
354 Galaxy *gt = &gp->galaxies[i];
356 for (j = 0; j < gp->galaxies[i].nstars; ++j) {
357 Star *st = >->stars[j];
358 XPoint *newp = >->newpoints[j];
359 double v0 = st->vel[0];
360 double v1 = st->vel[1];
361 double v2 = st->vel[2];
363 for (k = 0; k < gp->ngalaxies; ++k) {
364 Galaxy *gtk = &gp->galaxies[k];
365 double d0 = gtk->pos[0] - st->pos[0];
366 double d1 = gtk->pos[1] - st->pos[1];
367 double d2 = gtk->pos[2] - st->pos[2];
369 d = d0 * d0 + d1 * d1 + d2 * d2;
371 d = gtk->mass / (d * sqrt(d)) * DELTAT * DELTAT * QCONS;
373 d = gtk->mass / (eps * sqrt(eps));
387 newp->x = (short) (((cox * st->pos[0]) - (six * st->pos[2])) *
388 gp->scale) + gp->midx;
389 newp->y = (short) (((cor * st->pos[1]) - (sir * ((six * st->pos[0]) +
390 (cox * st->pos[2]))))
391 * gp->scale) + gp->midy;
395 for (k = i + 1; k < gp->ngalaxies; ++k) {
396 Galaxy *gtk = &gp->galaxies[k];
397 double d0 = gtk->pos[0] - gt->pos[0];
398 double d1 = gtk->pos[1] - gt->pos[1];
399 double d2 = gtk->pos[2] - gt->pos[2];
401 d = d0 * d0 + d1 * d1 + d2 * d2;
403 d = 1 / (d * sqrt(d)) * DELTAT * QCONS;
405 d = 1 / (EPSILON * sqrt_EPSILON) * DELTAT * QCONS;
410 gt->vel[0] += d0 * gtk->mass;
411 gt->vel[1] += d1 * gtk->mass;
412 gt->vel[2] += d2 * gtk->mass;
413 gtk->vel[0] -= d0 * gt->mass;
414 gtk->vel[1] -= d1 * gt->mass;
415 gtk->vel[2] -= d2 * gt->mass;
418 gt->pos[0] += gt->vel[0] * DELTAT;
419 gt->pos[1] += gt->vel[1] * DELTAT;
420 gt->pos[2] += gt->vel[2] * DELTAT;
423 XSetForeground(display, gc, MI_WIN_BLACK_PIXEL(mi));
424 XDrawPoints(display, window, gc, gt->oldpoints, gt->nstars,
427 XSetForeground(display, gc, MI_PIXEL(mi, COLORSTEP * gt->galcol));
428 XDrawPoints(display, window, gc, gt->newpoints, gt->nstars,
431 dummy = gt->oldpoints;
432 gt->oldpoints = gt->newpoints;
433 gt->newpoints = dummy;
437 if (gp->step > gp->f_hititerations * 4)
442 release_galaxy(ModeInfo * mi)
444 if (universes != NULL) {
447 for (screen = 0; screen < MI_NUM_SCREENS(mi); screen++)
448 free_galaxies(&universes[screen]);
449 (void) free((void *) universes);
455 refresh_galaxy(ModeInfo * mi)
457 /* Do nothing, it will refresh by itself */
460 XSCREENSAVER_MODULE ("Galaxy", galaxy)