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