git.hungrycats.org Git - xscreensaver/blob - hacks/demon.c

   1 /* -*- Mode: C; tab-width: 4 -*- */
   2 /* demon --- David Griffeath's cellular automata */
   3
   4 #if 0
   5 static const char sccsid[] = "@(#)demon.c       5.00 2000/11/01 xlockmore";
   6 #endif
   7
   8 /*-
   9  * Copyright (c) 1995 by David Bagley.
  10  *
  11  * Permission to use, copy, modify, and distribute this software and its
  12  * documentation for any purpose and without fee is hereby granted,
  13  * provided that the above copyright notice appear in all copies and that
  14  * both that copyright notice and this permission notice appear in
  15  * supporting documentation.
  16  *
  17  * This file is provided AS IS with no warranties of any kind.  The author
  18  * shall have no liability with respect to the infringement of copyrights,
  19  * trade secrets or any patents by this file or any part thereof.  In no
  20  * event will the author be liable for any lost revenue or profits or
  21  * other special, indirect and consequential damages.
  22  *
  23  * Revision History:
  24  * 01-Nov-2000: Allocation checks
  25  * 10-May-1997: Compatible with xscreensaver
  26  * 16-Apr-1997: -neighbors 3, 9 (not sound mathematically), 12, and 8 added
  27  * 30-May-1996: Ron Hitchens <ron@idiom.com>
  28  *            Fixed memory management that caused leaks
  29  * 14-Apr-1996: -neighbors 6 runtime-time option added
  30  * 21-Aug-1995: Coded from A.K. Dewdney's "Computer Recreations", Scientific
  31  *              American Magazine" Aug 1989 pp 102-105.  Also very similar
  32  *              to hodgepodge machine described in A.K. Dewdney's "Computer
  33  *              Recreations", Scientific American Magazine" Aug 1988
  34  *              pp 104-107.  Also used life.c as a guide.
  35  */
  36
  37 /*-
  38  * A cellular universe of 4 phases debris, droplets, defects, and demons.
  39  */
  40
  41 /*-
  42   Grid     Number of Neighbors
  43   ----     ------------------
  44   Square   4 or 8
  45   Hexagon  6
  46   Triangle 3, 9, or 12
  47 */
  48
  49 #ifndef HAVE_COCOA
  50 # define DO_STIPPLE
  51 #endif
  52
  53 #ifdef STANDALONE
  54 # define MODE_demon
  55 # define DEFAULTS       "*delay:   50000 \n" \
  56                                         "*count:   0     \n" \
  57                                         "*cycles:  1000  \n" \
  58                                         "*size:    -7    \n" \
  59                                         "*ncolors: 64    \n" \
  60                                         "*fpsSolid: true    \n" \
  61
  62 # define demon_handle_event 0
  63 # define UNIFORM_COLORS
  64 # include "xlockmore.h"         /* in xscreensaver distribution */
  65 #else /* STANDALONE */
  66 # include "xlock.h"             /* in xlockmore distribution */
  67 #endif /* STANDALONE */
  68 #include "automata.h"
  69
  70 #ifdef MODE_demon
  71
  72 /*-
  73  * neighbors of 0 randomizes it between 3, 4, 6, 8, 9, and 12.
  74  */
  75 #define DEF_NEIGHBORS  "0"      /* choose random value */
  76
  77 static int  neighbors;
  78
  79 static XrmOptionDescRec opts[] =
  80 {
  81         {"-neighbors", ".demon.neighbors", XrmoptionSepArg, 0}
  82 };
  83
  84 static argtype vars[] =
  85 {
  86         {&neighbors, "neighbors", "Neighbors", DEF_NEIGHBORS, t_Int}
  87 };
  88 static OptionStruct desc[] =
  89 {
  90         {"-neighbors num", "squares 4 or 8, hexagons 6, triangles 3, 9 or 12"}
  91 };
  92
  93 ENTRYPOINT ModeSpecOpt demon_opts =
  94 {sizeof opts / sizeof opts[0], opts, sizeof vars / sizeof vars[0], vars, desc};
  95
  96 #ifdef USE_MODULES
  97 ModStruct   demon_description =
  98 {"demon", "init_demon", "draw_demon", "release_demon",
  99  "refresh_demon", "init_demon", (char *) NULL, &demon_opts,
 100  50000, 0, 1000, -7, 64, 1.0, "",
 101  "Shows Griffeath's cellular automata", 0, NULL};
 102
 103 #endif
 104
 105 #define DEMONBITS(n,w,h)\
 106   if ((dp->pixmaps[dp->init_bits]=\
 107   XCreatePixmapFromBitmapData(display,window,(char *)n,w,h,1,0,1))==None){\
 108   free_demon(display,dp); return;} else {dp->init_bits++;}
 109
 110 #define REDRAWSTEP 2000         /* How many cells to draw per cycle */
 111 #define MINSTATES 2
 112 #define MINGRIDSIZE 24
 113 #define MINSIZE 4
 114 #define NEIGHBORKINDS 6
 115
 116 /* Singly linked list */
 117 typedef struct _CellList {
 118         XPoint      pt;
 119         struct _CellList *next;
 120 } CellList;
 121
 122 typedef struct {
 123         int         generation;
 124         int         xs, ys;
 125         int         xb, yb;
 126         int         nrows, ncols;
 127         int         width, height;
 128         int         states;
 129         int         state;
 130         int         redrawing, redrawpos;
 131         int        *ncells;
 132         CellList  **cellList;
 133         unsigned char *oldcell, *newcell;
 134         int         neighbors;
 135         int         init_bits;
 136         GC          stippledGC;
 137         Pixmap      pixmaps[NUMSTIPPLES - 1];
 138         union {
 139                 XPoint      hexagon[6];
 140                 XPoint      triangle[2][3];
 141         } shape;
 142 } demonstruct;
 143
 144 static char plots[2][NEIGHBORKINDS] =
 145 {
 146         {3, 4, 6, 8, 9, 12},    /* Neighborhoods */
 147         {12, 16, 18, 20, 22, 24}        /* Number of states */
 148 };
 149
 150 static demonstruct *demons = (demonstruct *) NULL;
 151
 152 static void
 153 drawcell(ModeInfo * mi, int col, int row, unsigned char state)
 154 {
 155         demonstruct *dp = &demons[MI_SCREEN(mi)];
 156         GC          gc;
 157
 158         if (!state) {
 159                 XSetForeground(MI_DISPLAY(mi), MI_GC(mi), MI_BLACK_PIXEL(mi));
 160                 gc = MI_GC(mi);
 161         } else if (MI_NPIXELS(mi) >= NUMSTIPPLES) {
 162                 XSetForeground(MI_DISPLAY(mi), MI_GC(mi),
 163                            MI_PIXEL(mi, (((int) state - 1) * MI_NPIXELS(mi) /
 164                                          (dp->states - 1)) % MI_NPIXELS(mi)));
 165                 gc = MI_GC(mi);
 166         } else {
 167                 XGCValues   gcv;
 168
 169 #ifdef DO_STIPPLE
 170                 gcv.stipple = dp->pixmaps[(state - 1) % (NUMSTIPPLES - 1)];
 171 #endif /* DO_STIPPLE */
 172                 gcv.foreground = MI_WHITE_PIXEL(mi);
 173                 gcv.background = MI_BLACK_PIXEL(mi);
 174                 XChangeGC(MI_DISPLAY(mi), dp->stippledGC,
 175                           GCStipple | GCForeground | GCBackground, &gcv);
 176                 gc = dp->stippledGC;
 177         }
 178         if (dp->neighbors == 6) {
 179                 int         ccol = 2 * col + !(row & 1), crow = 2 * row;
 180
 181                 dp->shape.hexagon[0].x = dp->xb + ccol * dp->xs;
 182                 dp->shape.hexagon[0].y = dp->yb + crow * dp->ys;
 183                 if (dp->xs == 1 && dp->ys == 1)
 184                         XDrawPoint(MI_DISPLAY(mi), MI_WINDOW(mi),
 185                                        gc, dp->shape.hexagon[0].x, dp->shape.hexagon[0].y);
 186                 else
 187                         XFillPolygon(MI_DISPLAY(mi), MI_WINDOW(mi), gc,
 188                             dp->shape.hexagon, 6, Convex, CoordModePrevious);
 189         } else if (dp->neighbors == 4 || dp->neighbors == 8) {
 190                 XFillRectangle(MI_DISPLAY(mi), MI_WINDOW(mi), gc,
 191                 dp->xb + dp->xs * col, dp->yb + dp->ys * row,
 192                 dp->xs - (dp->xs > 3), dp->ys - (dp->ys > 3));
 193         } else {                /* TRI */
 194                 int         orient = (col + row) % 2;   /* O left 1 right */
 195
 196                 dp->shape.triangle[orient][0].x = dp->xb + col * dp->xs;
 197                 dp->shape.triangle[orient][0].y = dp->yb + row * dp->ys;
 198                 if (dp->xs <= 3 || dp->ys <= 3)
 199                         XDrawPoint(MI_DISPLAY(mi), MI_WINDOW(mi), gc,
 200                         ((orient) ? -1 : 1) + dp->shape.triangle[orient][0].x,
 201                                        dp->shape.triangle[orient][0].y);
 202                 else {
 203                         if (orient)
 204                                 dp->shape.triangle[orient][0].x += (dp->xs / 2 - 1);
 205                         else
 206                                 dp->shape.triangle[orient][0].x -= (dp->xs / 2 - 1);
 207                         XFillPolygon(MI_DISPLAY(mi), MI_WINDOW(mi), gc,
 208                                      dp->shape.triangle[orient], 3, Convex, CoordModePrevious);
 209
 210                 }
 211         }
 212 }
 213
 214 static Bool
 215 addtolist(ModeInfo * mi, int col, int row, unsigned char state)
 216 {
 217         demonstruct *dp = &demons[MI_SCREEN(mi)];
 218         CellList   *current;
 219
 220         current = dp->cellList[state];
 221         if ((dp->cellList[state] = (CellList *)
 222                 malloc(sizeof (CellList))) == NULL) {
 223                 return False;
 224         }
 225         dp->cellList[state]->pt.x = col;
 226         dp->cellList[state]->pt.y = row;
 227         dp->cellList[state]->next = current;
 228         dp->ncells[state]++;
 229         return True;
 230 }
 231
 232 #ifdef DEBUG
 233 static void
 234 print_state(ModeInfo * mi, int state)
 235 {
 236         demonstruct *dp = &demons[MI_SCREEN(mi)];
 237         CellList   *locallist;
 238         int         i = 0;
 239
 240         locallist = dp->cellList[state];
 241         (void) printf("state %d\n", state);
 242         while (locallist) {
 243                 (void) printf("%d       x %d, y %d\n", i,
 244                               locallist->pt.x, locallist->pt.y);
 245                 locallist = locallist->next;
 246                 i++;
 247         }
 248 }
 249
 250 #endif
 251
 252 static void
 253 free_state(demonstruct * dp, int state)
 254 {
 255         CellList   *current;
 256
 257         while (dp->cellList[state]) {
 258                 current = dp->cellList[state];
 259                 dp->cellList[state] = dp->cellList[state]->next;
 260                 (void) free((void *) current);
 261         }
 262         dp->cellList[state] = (CellList *) NULL;
 263         if (dp->ncells != NULL)
 264                 dp->ncells[state] = 0;
 265 }
 266
 267
 268 static void
 269 free_list(demonstruct * dp)
 270 {
 271         int         state;
 272
 273         for (state = 0; state < dp->states; state++)
 274                 free_state(dp, state);
 275         (void) free((void *) dp->cellList);
 276         dp->cellList = (CellList **) NULL;
 277 }
 278
 279 static void
 280 free_struct(demonstruct * dp)
 281 {
 282         if (dp->cellList != NULL) {
 283                 free_list(dp);
 284         }
 285         if (dp->ncells != NULL) {
 286                 (void) free((void *) dp->ncells);
 287                 dp->ncells = (int *) NULL;
 288         }
 289         if (dp->oldcell != NULL) {
 290                 (void) free((void *) dp->oldcell);
 291                 dp->oldcell = (unsigned char *) NULL;
 292         }
 293         if (dp->newcell != NULL) {
 294                 (void) free((void *) dp->newcell);
 295                 dp->newcell = (unsigned char *) NULL;
 296         }
 297 }
 298
 299 static void
 300 free_demon(Display *display, demonstruct *dp)
 301 {
 302         int         shade;
 303
 304         if (dp->stippledGC != None) {
 305                 XFreeGC(display, dp->stippledGC);
 306                 dp->stippledGC = None;
 307         }
 308         for (shade = 0; shade < dp->init_bits; shade++) {
 309                 XFreePixmap(display, dp->pixmaps[shade]);
 310         }
 311         dp->init_bits = 0;
 312         free_struct(dp);
 313 }
 314
 315 static Bool
 316 draw_state(ModeInfo * mi, int state)
 317 {
 318         demonstruct *dp = &demons[MI_SCREEN(mi)];
 319         GC          gc;
 320         XRectangle *rects;
 321         CellList   *current;
 322
 323         if (!state) {
 324                 XSetForeground(MI_DISPLAY(mi), MI_GC(mi), MI_BLACK_PIXEL(mi));
 325                 gc = MI_GC(mi);
 326         } else if (MI_NPIXELS(mi) >= NUMSTIPPLES) {
 327                 XSetForeground(MI_DISPLAY(mi), MI_GC(mi),
 328                            MI_PIXEL(mi, (((int) state - 1) * MI_NPIXELS(mi) /
 329                                          (dp->states - 1)) % MI_NPIXELS(mi)));
 330                 gc = MI_GC(mi);
 331         } else {
 332                 XGCValues   gcv;
 333
 334 #ifdef DO_STIPPLE
 335                 gcv.stipple = dp->pixmaps[(state - 1) % (NUMSTIPPLES - 1)];
 336 #endif /* DO_STIPPLE */
 337                 gcv.foreground = MI_WHITE_PIXEL(mi);
 338                 gcv.background = MI_BLACK_PIXEL(mi);
 339                 XChangeGC(MI_DISPLAY(mi), dp->stippledGC,
 340                           GCStipple | GCForeground | GCBackground, &gcv);
 341                 gc = dp->stippledGC;
 342         }
 343         if (dp->neighbors == 6) {       /* Draw right away, slow */
 344                 current = dp->cellList[state];
 345                 while (current) {
 346                         int         col, row, ccol, crow;
 347
 348                         col = current->pt.x;
 349                         row = current->pt.y;
 350                         ccol = 2 * col + !(row & 1), crow = 2 * row;
 351                         dp->shape.hexagon[0].x = dp->xb + ccol * dp->xs;
 352                         dp->shape.hexagon[0].y = dp->yb + crow * dp->ys;
 353                         if (dp->xs == 1 && dp->ys == 1)
 354                                 XDrawPoint(MI_DISPLAY(mi), MI_WINDOW(mi),
 355                                                gc, dp->shape.hexagon[0].x, dp->shape.hexagon[0].y);
 356                         else
 357                                 XFillPolygon(MI_DISPLAY(mi), MI_WINDOW(mi), gc,
 358                                              dp->shape.hexagon, 6, Convex, CoordModePrevious);
 359                         current = current->next;
 360                 }
 361         } else if (dp->neighbors == 4 || dp->neighbors == 8) {
 362                 /* Take advantage of XDrawRectangles */
 363                 int         ncells = 0;
 364
 365                 /* Create Rectangle list from part of the cellList */
 366                 if ((rects = (XRectangle *) malloc(dp->ncells[state] *
 367                          sizeof (XRectangle))) == NULL) {
 368                         return False;
 369                 }
 370                 current = dp->cellList[state];
 371                 while (current) {
 372                         rects[ncells].x = dp->xb + current->pt.x * dp->xs;
 373                         rects[ncells].y = dp->yb + current->pt.y * dp->ys;
 374                         rects[ncells].width = dp->xs - (dp->xs > 3);
 375                         rects[ncells].height = dp->ys - (dp->ys > 3);
 376                         current = current->next;
 377                         ncells++;
 378                 }
 379                 /* Finally get to draw */
 380                 XFillRectangles(MI_DISPLAY(mi), MI_WINDOW(mi), gc, rects, ncells);
 381                 /* Free up rects list and the appropriate part of the cellList */
 382                 (void) free((void *) rects);
 383         } else {                /* TRI */
 384                 current = dp->cellList[state];
 385                 while (current) {
 386                         int         col, row, orient;
 387
 388                         col = current->pt.x;
 389                         row = current->pt.y;
 390                         orient = (col + row) % 2;       /* O left 1 right */
 391                         dp->shape.triangle[orient][0].x = dp->xb + col * dp->xs;
 392                         dp->shape.triangle[orient][0].y = dp->yb + row * dp->ys;
 393                         if (dp->xs <= 3 || dp->ys <= 3)
 394                                 XDrawPoint(MI_DISPLAY(mi), MI_WINDOW(mi), gc,
 395                                                ((orient) ? -1 : 1) + dp->shape.triangle[orient][0].x,
 396                                       dp->shape.triangle[orient][0].y);
 397                         else {
 398                                 if (orient)
 399                                         dp->shape.triangle[orient][0].x += (dp->xs / 2 - 1);
 400                                 else
 401                                         dp->shape.triangle[orient][0].x -= (dp->xs / 2 - 1);
 402                                 XFillPolygon(MI_DISPLAY(mi), MI_WINDOW(mi), gc,
 403                                              dp->shape.triangle[orient], 3, Convex, CoordModePrevious);
 404                         }
 405                         current = current->next;
 406                 }
 407         }
 408         free_state(dp, state);
 409         return True;
 410 }
 411
 412 static void
 413 RandomSoup(ModeInfo * mi)
 414 {
 415         demonstruct *dp = &demons[MI_SCREEN(mi)];
 416         int         row, col, mrow = 0;
 417
 418         for (row = 0; row < dp->nrows; ++row) {
 419                 for (col = 0; col < dp->ncols; ++col) {
 420                         dp->oldcell[col + mrow] =
 421                                 (unsigned char) LRAND() % ((unsigned char) dp->states);
 422                         if (!addtolist(mi, col, row, dp->oldcell[col + mrow]))
 423                                 return; /* sparse soup */
 424                 }
 425                 mrow += dp->ncols;
 426         }
 427 }
 428
 429 ENTRYPOINT void
 430 init_demon (ModeInfo * mi)
 431 {
 432         Display    *display = MI_DISPLAY(mi);
 433         int         size = MI_SIZE(mi), nk;
 434         demonstruct *dp;
 435
 436         if (demons == NULL) {
 437                 if ((demons = (demonstruct *) calloc(MI_NUM_SCREENS(mi),
 438                                               sizeof (demonstruct))) == NULL)
 439                         return;
 440         }
 441         dp = &demons[MI_SCREEN(mi)];
 442
 443         dp->generation = 0;
 444         dp->redrawing = 0;
 445 #ifdef DO_STIPPLE
 446         if (MI_NPIXELS(mi) < NUMSTIPPLES) {
 447           Window window = MI_WINDOW(mi);
 448           if (dp->stippledGC == None) {
 449                         XGCValues   gcv;
 450
 451                         gcv.fill_style = FillOpaqueStippled;
 452                         if ((dp->stippledGC = XCreateGC(display, window,
 453                                  GCFillStyle, &gcv)) == None) {
 454                                 free_demon(display, dp);
 455                                 return;
 456                         }
 457                 }
 458                 if (dp->init_bits == 0) {
 459                         int         i;
 460
 461                         for (i = 1; i < NUMSTIPPLES; i++) {
 462                                 DEMONBITS(stipples[i], STIPPLESIZE, STIPPLESIZE);
 463                         }
 464                 }
 465         }
 466 #endif /* DO_STIPPLE */
 467         free_struct(dp);
 468
 469         for (nk = 0; nk < NEIGHBORKINDS; nk++) {
 470                 if (neighbors == plots[0][nk]) {
 471                         dp->neighbors = plots[0][nk];
 472                         break;
 473                 }
 474                 if (nk == NEIGHBORKINDS - 1) {
 475                         nk = NRAND(NEIGHBORKINDS);
 476                         dp->neighbors = plots[0][nk];
 477                         break;
 478                 }
 479         }
 480
 481         dp->states = MI_COUNT(mi);
 482         if (dp->states < -MINSTATES)
 483                 dp->states = NRAND(-dp->states - MINSTATES + 1) + MINSTATES;
 484         else if (dp->states < MINSTATES)
 485                 dp->states = plots[1][nk];
 486         if ((dp->cellList = (CellList **) calloc(dp->states,
 487                 sizeof (CellList *))) == NULL) {
 488                 free_demon(display, dp);
 489                 return;
 490         }
 491         if ((dp->ncells = (int *) calloc(dp->states, sizeof (int))) == NULL) {
 492                 free_demon(display, dp);
 493                 return;
 494         }
 495
 496         dp->state = 0;
 497
 498         dp->width = MI_WIDTH(mi);
 499         dp->height = MI_HEIGHT(mi);
 500
 501         if (dp->neighbors == 6) {
 502                 int         nccols, ncrows, i;
 503
 504                 if (dp->width < 8)
 505                         dp->width = 8;
 506                 if (dp->height < 8)
 507                         dp->height = 8;
 508                 if (size < -MINSIZE)
 509                         dp->ys = NRAND(MIN(-size, MAX(MINSIZE, MIN(dp->width, dp->height) /
 510                                       MINGRIDSIZE)) - MINSIZE + 1) + MINSIZE;
 511                 else if (size < MINSIZE) {
 512                         if (!size)
 513                                 dp->ys = MAX(MINSIZE, MIN(dp->width, dp->height) / MINGRIDSIZE);
 514                         else
 515                                 dp->ys = MINSIZE;
 516                 } else
 517                         dp->ys = MIN(size, MAX(MINSIZE, MIN(dp->width, dp->height) /
 518                                                MINGRIDSIZE));
 519                 dp->xs = dp->ys;
 520                 nccols = MAX(dp->width / dp->xs - 2, 2);
 521                 ncrows = MAX(dp->height / dp->ys - 1, 4);
 522                 dp->ncols = nccols / 2;
 523                 dp->nrows = 2 * (ncrows / 4);
 524                 dp->xb = (dp->width - dp->xs * nccols) / 2 + dp->xs / 2;
 525                 dp->yb = (dp->height - dp->ys * (ncrows / 2) * 2) / 2 + dp->ys - 2;
 526                 for (i = 0; i < 6; i++) {
 527                         dp->shape.hexagon[i].x = (dp->xs - 1) * hexagonUnit[i].x;
 528                         dp->shape.hexagon[i].y = ((dp->ys - 1) * hexagonUnit[i].y / 2) * 4 / 3;
 529                 }
 530         } else if (dp->neighbors == 4 || dp->neighbors == 8) {
 531                 if (size < -MINSIZE)
 532                         dp->ys = NRAND(MIN(-size, MAX(MINSIZE, MIN(dp->width, dp->height) /
 533                                       MINGRIDSIZE)) - MINSIZE + 1) + MINSIZE;
 534                 else if (size < MINSIZE) {
 535                         if (!size)
 536                                 dp->ys = MAX(MINSIZE, MIN(dp->width, dp->height) / MINGRIDSIZE);
 537                         else
 538                                 dp->ys = MINSIZE;
 539                 } else
 540                         dp->ys = MIN(size, MAX(MINSIZE, MIN(dp->width, dp->height) /
 541                                                MINGRIDSIZE));
 542                 dp->xs = dp->ys;
 543                 dp->ncols = MAX(dp->width / dp->xs, 2);
 544                 dp->nrows = MAX(dp->height / dp->ys, 2);
 545                 dp->xb = (dp->width - dp->xs * dp->ncols) / 2;
 546                 dp->yb = (dp->height - dp->ys * dp->nrows) / 2;
 547         } else {                /* TRI */
 548                 int         orient, i;
 549
 550                 if (dp->width < 2)
 551                         dp->width = 2;
 552                 if (dp->height < 2)
 553                         dp->height = 2;
 554                 if (size < -MINSIZE)
 555                         dp->ys = NRAND(MIN(-size, MAX(MINSIZE, MIN(dp->width, dp->height) /
 556                                       MINGRIDSIZE)) - MINSIZE + 1) + MINSIZE;
 557                 else if (size < MINSIZE) {
 558                         if (!size)
 559                                 dp->ys = MAX(MINSIZE, MIN(dp->width, dp->height) / MINGRIDSIZE);
 560                         else
 561                                 dp->ys = MINSIZE;
 562                 } else
 563                         dp->ys = MIN(size, MAX(MINSIZE, MIN(dp->width, dp->height) /
 564                                                MINGRIDSIZE));
 565                 dp->xs = (int) (1.52 * dp->ys);
 566                 dp->ncols = (MAX(dp->width / dp->xs - 1, 2) / 2) * 2;
 567                 dp->nrows = (MAX(dp->height / dp->ys - 1, 2) / 2) * 2;
 568                 dp->xb = (dp->width - dp->xs * dp->ncols) / 2 + dp->xs / 2;
 569                 dp->yb = (dp->height - dp->ys * dp->nrows) / 2 + dp->ys / 2;
 570                 for (orient = 0; orient < 2; orient++) {
 571                         for (i = 0; i < 3; i++) {
 572                                 dp->shape.triangle[orient][i].x =
 573                                         (dp->xs - 2) * triangleUnit[orient][i].x;
 574                                 dp->shape.triangle[orient][i].y =
 575                                         (dp->ys - 2) * triangleUnit[orient][i].y;
 576                         }
 577                 }
 578         }
 579
 580         MI_CLEARWINDOW(mi);
 581
 582         if ((dp->oldcell = (unsigned char *)
 583                 malloc(dp->ncols * dp->nrows * sizeof (unsigned char))) == NULL) {
 584                 free_demon(display, dp);
 585                 return;
 586         }
 587
 588         if ((dp->newcell = (unsigned char *)
 589                 malloc(dp->ncols * dp->nrows * sizeof (unsigned char))) == NULL) {
 590                 free_demon(display, dp);
 591                 return;
 592         }
 593
 594         RandomSoup(mi);
 595 }
 596
 597 ENTRYPOINT void
 598 draw_demon (ModeInfo * mi)
 599 {
 600         int         i, j, k, l, mj = 0, ml;
 601         demonstruct *dp;
 602
 603         if (demons == NULL)
 604                 return;
 605         dp = &demons[MI_SCREEN(mi)];
 606         if (dp->cellList == NULL)
 607                 return;
 608
 609         MI_IS_DRAWN(mi) = True;
 610         if (dp->state >= dp->states) {
 611                 (void) memcpy((char *) dp->newcell, (char *) dp->oldcell,
 612                               dp->ncols * dp->nrows * sizeof (unsigned char));
 613
 614                 if (dp->neighbors == 6) {
 615                         for (j = 0; j < dp->nrows; j++) {
 616                                 for (i = 0; i < dp->ncols; i++) {
 617                                         /* NE */
 618                                         if (!(j & 1))
 619                                                 k = (i + 1 == dp->ncols) ? 0 : i + 1;
 620                                         else
 621                                                 k = i;
 622                                         l = (!j) ? dp->nrows - 1 : j - 1;
 623                                         ml = l * dp->ncols;
 624                                         if (dp->oldcell[k + ml] ==
 625                                             (int) (dp->oldcell[i + mj] + 1) % dp->states)
 626                                                 dp->newcell[i + mj] = dp->oldcell[k + ml];
 627                                         /* E */
 628                                         k = (i + 1 == dp->ncols) ? 0 : i + 1;
 629                                         ml = mj;
 630                                         if (dp->oldcell[k + ml] ==
 631                                             (int) (dp->oldcell[i + mj] + 1) % dp->states)
 632                                                 dp->newcell[i + mj] = dp->oldcell[k + ml];
 633                                         /* SE */
 634                                         if (!(j & 1))
 635                                                 k = (i + 1 == dp->ncols) ? 0 : i + 1;
 636                                         else
 637                                                 k = i;
 638                                         l = (j + 1 == dp->nrows) ? 0 : j + 1;
 639                                         ml = l * dp->ncols;
 640                                         if (dp->oldcell[k + ml] ==
 641                                             (int) (dp->oldcell[i + mj] + 1) % dp->states)
 642                                                 dp->newcell[i + mj] = dp->oldcell[k + ml];
 643                                         /* SW */
 644                                         if (j & 1)
 645                                                 k = (!i) ? dp->ncols - 1 : i - 1;
 646                                         else
 647                                                 k = i;
 648                                         l = (j + 1 == dp->nrows) ? 0 : j + 1;
 649                                         ml = l * dp->ncols;
 650                                         if (dp->oldcell[k + ml] ==
 651                                             (int) (dp->oldcell[i + mj] + 1) % dp->states)
 652                                                 dp->newcell[i + mj] = dp->oldcell[k + ml];
 653                                         /* W */
 654                                         k = (!i) ? dp->ncols - 1 : i - 1;
 655                                         ml = mj;
 656                                         if (dp->oldcell[k + ml] ==
 657                                             (int) (dp->oldcell[i + mj] + 1) % dp->states)
 658                                                 dp->newcell[i + mj] = dp->oldcell[k + ml];
 659                                         /* NW */
 660                                         if (j & 1)
 661                                                 k = (!i) ? dp->ncols - 1 : i - 1;
 662                                         else
 663                                                 k = i;
 664                                         l = (!j) ? dp->nrows - 1 : j - 1;
 665                                         ml = l * dp->ncols;
 666                                         if (dp->oldcell[k + ml] ==
 667                                             (int) (dp->oldcell[i + mj] + 1) % dp->states)
 668                                                 dp->newcell[i + mj] = dp->oldcell[k + ml];
 669                                 }
 670                                 mj += dp->ncols;
 671                         }
 672                 } else if (dp->neighbors == 4 || dp->neighbors == 8) {
 673                         for (j = 0; j < dp->nrows; j++) {
 674                                 for (i = 0; i < dp->ncols; i++) {
 675                                         /* N */
 676                                         k = i;
 677                                         l = (!j) ? dp->nrows - 1 : j - 1;
 678                                         ml = l * dp->ncols;
 679                                         if (dp->oldcell[k + ml] ==
 680                                             (int) (dp->oldcell[i + mj] + 1) % dp->states)
 681                                                 dp->newcell[i + mj] = dp->oldcell[k + ml];
 682                                         /* E */
 683                                         k = (i + 1 == dp->ncols) ? 0 : i + 1;
 684                                         ml = mj;
 685                                         if (dp->oldcell[k + ml] ==
 686                                             (int) (dp->oldcell[i + mj] + 1) % dp->states)
 687                                                 dp->newcell[i + mj] = dp->oldcell[k + ml];
 688                                         /* S */
 689                                         k = i;
 690                                         l = (j + 1 == dp->nrows) ? 0 : j + 1;
 691                                         ml = l * dp->ncols;
 692                                         if (dp->oldcell[k + ml] ==
 693                                             (int) (dp->oldcell[i + mj] + 1) % dp->states)
 694                                                 dp->newcell[i + mj] = dp->oldcell[k + ml];
 695                                         /* W */
 696                                         k = (!i) ? dp->ncols - 1 : i - 1;
 697                                         /*l = j;*/
 698                                         ml = mj;
 699                                         if (dp->oldcell[k + ml] ==
 700                                             (int) (dp->oldcell[i + mj] + 1) % dp->states)
 701                                                 dp->newcell[i + mj] = dp->oldcell[k + ml];
 702                                 }
 703                                 mj += dp->ncols;
 704                         }
 705                         if (dp->neighbors == 8) {
 706                                 mj = 0;
 707                                 for (j = 0; j < dp->nrows; j++) {
 708                                         for (i = 0; i < dp->ncols; i++) {
 709                                                 /* NE */
 710                                                 k = (i + 1 == dp->ncols) ? 0 : i + 1;
 711                                                 l = (!j) ? dp->nrows - 1 : j - 1;
 712                                                 ml = l * dp->ncols;
 713                                                 if (dp->oldcell[k + ml] ==
 714                                                     (int) (dp->oldcell[i + mj] + 1) % dp->states)
 715                                                         dp->newcell[i + mj] = dp->oldcell[k + ml];
 716                                                 /* SE */
 717                                                 k = (i + 1 == dp->ncols) ? 0 : i + 1;
 718                                                 l = (j + 1 == dp->nrows) ? 0 : j + 1;
 719                                                 ml = l * dp->ncols;
 720                                                 if (dp->oldcell[k + ml] ==
 721                                                     (int) (dp->oldcell[i + mj] + 1) % dp->states)
 722                                                         dp->newcell[i + mj] = dp->oldcell[k + ml];
 723                                                 /* SW */
 724                                                 k = (!i) ? dp->ncols - 1 : i - 1;
 725                                                 l = (j + 1 == dp->nrows) ? 0 : j + 1;
 726                                                 ml = l * dp->ncols;
 727                                                 if (dp->oldcell[k + ml] ==
 728                                                     (int) (dp->oldcell[i + mj] + 1) % dp->states)
 729                                                         dp->newcell[i + mj] = dp->oldcell[k + ml];
 730                                                 /* NW */
 731                                                 k = (!i) ? dp->ncols - 1 : i - 1;
 732                                                 l = (!j) ? dp->nrows - 1 : j - 1;
 733                                                 ml = l * dp->ncols;
 734                                                 if (dp->oldcell[k + ml] ==
 735                                                     (int) (dp->oldcell[i + mj] + 1) % dp->states)
 736                                                         dp->newcell[i + mj] = dp->oldcell[k + ml];
 737                                         }
 738                                         mj += dp->ncols;
 739                                 }
 740                         }
 741                 } else if (dp->neighbors == 3 || dp->neighbors == 9 ||
 742                            dp->neighbors == 12) {
 743                         for (j = 0; j < dp->nrows; j++) {
 744                                 for (i = 0; i < dp->ncols; i++) {
 745                                         if ((i + j) % 2) {      /* right */
 746                                                 /* W */
 747                                                 k = (!i) ? dp->ncols - 1 : i - 1;
 748                                                 ml = mj;
 749                                                 if (dp->oldcell[k + ml] ==
 750                                                     (int) (dp->oldcell[i + mj] + 1) % dp->states)
 751                                                         dp->newcell[i + mj] = dp->oldcell[k + ml];
 752                                         } else {        /* left */
 753                                                 /* E */
 754                                                 k = (i + 1 == dp->ncols) ? 0 : i + 1;
 755                                                 ml = mj;
 756                                                 if (dp->oldcell[k + ml] ==
 757                                                     (int) (dp->oldcell[i + mj] + 1) % dp->states)
 758                                                         dp->newcell[i + mj] = dp->oldcell[k + ml];
 759                                         }
 760                                         /* N */
 761                                         k = i;
 762                                         l = (!j) ? dp->nrows - 1 : j - 1;
 763                                         ml = l * dp->ncols;
 764                                         if (dp->oldcell[k + ml] ==
 765                                             (int) (dp->oldcell[i + mj] + 1) % dp->states)
 766                                                 dp->newcell[i + mj] = dp->oldcell[k + ml];
 767                                         /* S */
 768                                         k = i;
 769                                         l = (j + 1 == dp->nrows) ? 0 : j + 1;
 770                                         ml = l * dp->ncols;
 771                                         if (dp->oldcell[k + ml] ==
 772                                             (int) (dp->oldcell[i + mj] + 1) % dp->states)
 773                                                 dp->newcell[i + mj] = dp->oldcell[k + ml];
 774                                 }
 775                                 mj += dp->ncols;
 776                         }
 777                         if (dp->neighbors == 9 || dp->neighbors == 12) {
 778                                 mj = 0;
 779                                 for (j = 0; j < dp->nrows; j++) {
 780                                         for (i = 0; i < dp->ncols; i++) {
 781                                                 /* NN */
 782                                                 k = i;
 783                                                 if (!j)
 784                                                         l = dp->nrows - 2;
 785                                                 else if (!(j - 1))
 786                                                         l = dp->nrows - 1;
 787                                                 else
 788                                                         l = j - 2;
 789                                                 ml = l * dp->ncols;
 790                                                 if (dp->oldcell[k + ml] ==
 791                                                     (int) (dp->oldcell[i + mj] + 1) % dp->states)
 792                                                         dp->newcell[i + mj] = dp->oldcell[k + ml];
 793                                                 /* SS */
 794                                                 k = i;
 795                                                 if (j + 1 == dp->nrows)
 796                                                         l = 1;
 797                                                 else if (j + 2 == dp->nrows)
 798                                                         l = 0;
 799                                                 else
 800                                                         l = j + 2;
 801                                                 ml = l * dp->ncols;
 802                                                 if (dp->oldcell[k + ml] ==
 803                                                     (int) (dp->oldcell[i + mj] + 1) % dp->states)
 804                                                         dp->newcell[i + mj] = dp->oldcell[k + ml];
 805                                                 /* NW */
 806                                                 k = (!i) ? dp->ncols - 1 : i - 1;
 807                                                 l = (!j) ? dp->nrows - 1 : j - 1;
 808                                                 ml = l * dp->ncols;
 809                                                 if (dp->oldcell[k + ml] ==
 810                                                     (int) (dp->oldcell[i + mj] + 1) % dp->states)
 811                                                         dp->newcell[i + mj] = dp->oldcell[k + ml];
 812                                                 /* NE */
 813                                                 k = (i + 1 == dp->ncols) ? 0 : i + 1;
 814                                                 l = (!j) ? dp->nrows - 1 : j - 1;
 815                                                 ml = l * dp->ncols;
 816                                                 if (dp->oldcell[k + ml] ==
 817                                                     (int) (dp->oldcell[i + mj] + 1) % dp->states)
 818                                                         dp->newcell[i + mj] = dp->oldcell[k + ml];
 819                                                 /* SW */
 820                                                 k = (!i) ? dp->ncols - 1 : i - 1;
 821                                                 l = (j + 1 == dp->nrows) ? 0 : j + 1;
 822                                                 ml = l * dp->ncols;
 823                                                 if (dp->oldcell[k + ml] ==
 824                                                     (int) (dp->oldcell[i + mj] + 1) % dp->states)
 825                                                         dp->newcell[i + mj] = dp->oldcell[k + ml];
 826                                                 /* SE */
 827                                                 k = (i + 1 == dp->ncols) ? 0 : i + 1;
 828                                                 l = (j + 1 == dp->nrows) ? 0 : j + 1;
 829                                                 ml = l * dp->ncols;
 830                                                 if (dp->oldcell[k + ml] ==
 831                                                     (int) (dp->oldcell[i + mj] + 1) % dp->states)
 832                                                         dp->newcell[i + mj] = dp->oldcell[k + ml];
 833                                         }
 834                                         mj += dp->ncols;
 835                                 }
 836                                 if (dp->neighbors == 12) {
 837                                         mj = 0;
 838                                         for (j = 0; j < dp->nrows; j++) {
 839                                                 for (i = 0; i < dp->ncols; i++) {
 840                                                         if ((i + j) % 2) {      /* right */
 841                                                                 /* NNW */
 842                                                                 k = (!i) ? dp->ncols - 1 : i - 1;
 843                                                                 if (!j)
 844                                                                         l = dp->nrows - 2;
 845                                                                 else if (!(j - 1))
 846                                                                         l = dp->nrows - 1;
 847                                                                 else
 848                                                                         l = j - 2;
 849                                                                 ml = l * dp->ncols;
 850                                                                 if (dp->oldcell[k + ml] ==
 851                                                                     (int) (dp->oldcell[i + mj] + 1) % dp->states)
 852                                                                         dp->newcell[i + mj] = dp->oldcell[k + ml];
 853                                                                 /* SSW */
 854                                                                 k = (!i) ? dp->ncols - 1 : i - 1;
 855                                                                 if (j + 1 == dp->nrows)
 856                                                                         l = 1;
 857                                                                 else if (j + 2 == dp->nrows)
 858                                                                         l = 0;
 859                                                                 else
 860                                                                         l = j + 2;
 861                                                                 ml = l * dp->ncols;
 862                                                                 if (dp->oldcell[k + ml] ==
 863                                                                     (int) (dp->oldcell[i + mj] + 1) % dp->states)
 864                                                                         dp->newcell[i + mj] = dp->oldcell[k + ml];
 865                                                                 /* EE */
 866                                                                 k = (i + 1 == dp->ncols) ? 0 : i + 1;
 867                                                                 /*l = j;*/
 868                                                                 ml = mj;
 869                                                                 if (dp->oldcell[k + ml] ==
 870                                                                     (int) (dp->oldcell[i + mj] + 1) % dp->states)
 871                                                                         dp->newcell[i + mj] = dp->oldcell[k + ml];
 872                                                         } else {        /* left */
 873                                                                 /* NNE */
 874                                                                 k = (i + 1 == dp->ncols) ? 0 : i + 1;
 875                                                                 if (!j)
 876                                                                         l = dp->nrows - 2;
 877                                                                 else if (!(j - 1))
 878                                                                         l = dp->nrows - 1;
 879                                                                 else
 880                                                                         l = j - 2;
 881                                                                 ml = l * dp->ncols;
 882                                                                 if (dp->oldcell[k + ml] ==
 883                                                                     (int) (dp->oldcell[i + mj] + 1) % dp->states)
 884                                                                         dp->newcell[i + mj] = dp->oldcell[k + ml];
 885                                                                 /* SSE */
 886                                                                 k = (i + 1 == dp->ncols) ? 0 : i + 1;
 887                                                                 if (j + 1 == dp->nrows)
 888                                                                         l = 1;
 889                                                                 else if (j + 2 == dp->nrows)
 890                                                                         l = 0;
 891                                                                 else
 892                                                                         l = j + 2;
 893                                                                 ml = l * dp->ncols;
 894                                                                 if (dp->oldcell[k + ml] ==
 895                                                                     (int) (dp->oldcell[i + mj] + 1) % dp->states)
 896                                                                         dp->newcell[i + mj] = dp->oldcell[k + ml];
 897                                                                 /* WW */
 898                                                                 k = (!i) ? dp->ncols - 1 : i - 1;
 899                                                                 /*l = j;*/
 900                                                                 ml = mj;
 901                                                                 if (dp->oldcell[k + ml] ==
 902                                                                     (int) (dp->oldcell[i + mj] + 1) % dp->states)
 903                                                                         dp->newcell[i + mj] = dp->oldcell[k + ml];
 904                                                         }
 905                                                 }
 906                                                 mj += dp->ncols;
 907                                         }
 908                                 }
 909                         }
 910                 }
 911                 mj = 0;
 912                 for (j = 0; j < dp->nrows; j++) {
 913                         for (i = 0; i < dp->ncols; i++)
 914                                 if (dp->oldcell[i + mj] != dp->newcell[i + mj]) {
 915                                         dp->oldcell[i + mj] = dp->newcell[i + mj];
 916                                         if (!addtolist(mi, i, j, dp->oldcell[i + mj])) {
 917                                                 free_demon(MI_DISPLAY(mi), dp);
 918                                                 return;
 919                                         }
 920                                 }
 921                         mj += dp->ncols;
 922                 }
 923                 if (++dp->generation > MI_CYCLES(mi))
 924                         init_demon(mi);
 925                 dp->state = 0;
 926         } else {
 927                 if (dp->ncells[dp->state])
 928                         if (!draw_state(mi, dp->state)) {
 929                                 free_demon(MI_DISPLAY(mi), dp);
 930                                 return;
 931                         }
 932                 dp->state++;
 933         }
 934         if (dp->redrawing) {
 935                 for (i = 0; i < REDRAWSTEP; i++) {
 936                         if (dp->oldcell[dp->redrawpos]) {
 937                                 drawcell(mi, dp->redrawpos % dp->ncols, dp->redrawpos / dp->ncols,
 938                                          dp->oldcell[dp->redrawpos]);
 939                         }
 940                         if (++(dp->redrawpos) >= dp->ncols * dp->nrows) {
 941                                 dp->redrawing = 0;
 942                                 break;
 943                         }
 944                 }
 945         }
 946 }
 947
 948
 949 ENTRYPOINT void
 950 reshape_demon(ModeInfo * mi, int width, int height)
 951 {
 952   XClearWindow (MI_DISPLAY (mi), MI_WINDOW(mi));
 953   init_demon (mi);
 954 }
 955
 956
 957 ENTRYPOINT void
 958 release_demon (ModeInfo * mi)
 959 {
 960         if (demons != NULL) {
 961                 int         screen;
 962
 963                 for (screen = 0; screen < MI_NUM_SCREENS(mi); screen++)
 964                         free_demon(MI_DISPLAY(mi), &demons[screen]);
 965                 (void) free((void *) demons);
 966                 demons = (demonstruct *) NULL;
 967         }
 968 }
 969
 970 ENTRYPOINT void
 971 refresh_demon (ModeInfo * mi)
 972 {
 973         demonstruct *dp;
 974
 975         if (demons == NULL)
 976                 return;
 977         dp = &demons[MI_SCREEN(mi)];
 978
 979         dp->redrawing = 1;
 980         dp->redrawpos = 0;
 981 }
 982
 983 XSCREENSAVER_MODULE ("Demon", demon)
 984
 985 #endif /* MODE_demon */