mdw@git.distorted.org.uk Git - sgt/puzzles/blob - fifteen.c

   1 /*
   2  * fifteen.c: standard 15-puzzle.
   3  */
   4
   5 #include <stdio.h>
   6 #include <stdlib.h>
   7 #include <string.h>
   8 #include <assert.h>
   9 #include <ctype.h>
  10 #include <math.h>
  11
  12 #include "puzzles.h"
  13
  14 #define TILE_SIZE 48
  15 #define BORDER    (TILE_SIZE / 2)
  16 #define HIGHLIGHT_WIDTH (TILE_SIZE / 20)
  17 #define COORD(x)  ( (x) * TILE_SIZE + BORDER )
  18 #define FROMCOORD(x)  ( ((x) - BORDER + TILE_SIZE) / TILE_SIZE - 1 )
  19
  20 #define ANIM_TIME 0.13F
  21 #define FLASH_FRAME 0.13F
  22
  23 #define X(state, i) ( (i) % (state)->w )
  24 #define Y(state, i) ( (i) / (state)->w )
  25 #define C(state, x, y) ( (y) * (state)->w + (x) )
  26
  27 enum {
  28     COL_BACKGROUND,
  29     COL_TEXT,
  30     COL_HIGHLIGHT,
  31     COL_LOWLIGHT,
  32     NCOLOURS
  33 };
  34
  35 struct game_params {
  36     int w, h;
  37 };
  38
  39 struct game_state {
  40     int w, h, n;
  41     int *tiles;
  42     int gap_pos;
  43     int completed;
  44     int just_used_solve;               /* used to suppress undo animation */
  45     int used_solve;                    /* used to suppress completion flash */
  46     int movecount;
  47 };
  48
  49 static game_params *default_params(void)
  50 {
  51     game_params *ret = snew(game_params);
  52
  53     ret->w = ret->h = 4;
  54
  55     return ret;
  56 }
  57
  58 static int game_fetch_preset(int i, char **name, game_params **params)
  59 {
  60     return FALSE;
  61 }
  62
  63 static void free_params(game_params *params)
  64 {
  65     sfree(params);
  66 }
  67
  68 static game_params *dup_params(game_params *params)
  69 {
  70     game_params *ret = snew(game_params);
  71     *ret = *params;                    /* structure copy */
  72     return ret;
  73 }
  74
  75 static void decode_params(game_params *ret, char const *string)
  76 {
  77     ret->w = ret->h = atoi(string);
  78     while (*string && isdigit(*string)) string++;
  79     if (*string == 'x') {
  80         string++;
  81         ret->h = atoi(string);
  82     }
  83 }
  84
  85 static char *encode_params(game_params *params, int full)
  86 {
  87     char data[256];
  88
  89     sprintf(data, "%dx%d", params->w, params->h);
  90
  91     return dupstr(data);
  92 }
  93
  94 static config_item *game_configure(game_params *params)
  95 {
  96     config_item *ret;
  97     char buf[80];
  98
  99     ret = snewn(3, config_item);
 100
 101     ret[0].name = "Width";
 102     ret[0].type = C_STRING;
 103     sprintf(buf, "%d", params->w);
 104     ret[0].sval = dupstr(buf);
 105     ret[0].ival = 0;
 106
 107     ret[1].name = "Height";
 108     ret[1].type = C_STRING;
 109     sprintf(buf, "%d", params->h);
 110     ret[1].sval = dupstr(buf);
 111     ret[1].ival = 0;
 112
 113     ret[2].name = NULL;
 114     ret[2].type = C_END;
 115     ret[2].sval = NULL;
 116     ret[2].ival = 0;
 117
 118     return ret;
 119 }
 120
 121 static game_params *custom_params(config_item *cfg)
 122 {
 123     game_params *ret = snew(game_params);
 124
 125     ret->w = atoi(cfg[0].sval);
 126     ret->h = atoi(cfg[1].sval);
 127
 128     return ret;
 129 }
 130
 131 static char *validate_params(game_params *params)
 132 {
 133     if (params->w < 2 && params->h < 2)
 134         return "Width and height must both be at least two";
 135
 136     return NULL;
 137 }
 138
 139 static int perm_parity(int *perm, int n)
 140 {
 141     int i, j, ret;
 142
 143     ret = 0;
 144
 145     for (i = 0; i < n-1; i++)
 146         for (j = i+1; j < n; j++)
 147             if (perm[i] > perm[j])
 148                 ret = !ret;
 149
 150     return ret;
 151 }
 152
 153 static char *new_game_desc(game_params *params, random_state *rs,
 154                            game_aux_info **aux)
 155 {
 156     int gap, n, i, x;
 157     int x1, x2, p1, p2, parity;
 158     int *tiles, *used;
 159     char *ret;
 160     int retlen;
 161
 162     n = params->w * params->h;
 163
 164     tiles = snewn(n, int);
 165     used = snewn(n, int);
 166
 167     for (i = 0; i < n; i++) {
 168         tiles[i] = -1;
 169         used[i] = FALSE;
 170     }
 171
 172     gap = random_upto(rs, n);
 173     tiles[gap] = 0;
 174     used[0] = TRUE;
 175
 176     /*
 177      * Place everything else except the last two tiles.
 178      */
 179     for (x = 0, i = n-1; i > 2; i--) {
 180         int k = random_upto(rs, i);
 181         int j;
 182
 183         for (j = 0; j < n; j++)
 184             if (!used[j] && (k-- == 0))
 185                 break;
 186
 187         assert(j < n && !used[j]);
 188         used[j] = TRUE;
 189
 190         while (tiles[x] >= 0)
 191             x++;
 192         assert(x < n);
 193         tiles[x] = j;
 194     }
 195
 196     /*
 197      * Find the last two locations, and the last two pieces.
 198      */
 199     while (tiles[x] >= 0)
 200         x++;
 201     assert(x < n);
 202     x1 = x;
 203     x++;
 204     while (tiles[x] >= 0)
 205         x++;
 206     assert(x < n);
 207     x2 = x;
 208
 209     for (i = 0; i < n; i++)
 210         if (!used[i])
 211             break;
 212     p1 = i;
 213     for (i = p1+1; i < n; i++)
 214         if (!used[i])
 215             break;
 216     p2 = i;
 217
 218     /*
 219      * Determine the required parity of the overall permutation.
 220      * This is the XOR of:
 221      *
 222      *  - The chessboard parity ((x^y)&1) of the gap square. The
 223      *    bottom right counts as even.
 224      *
 225      *  - The parity of n. (The target permutation is 1,...,n-1,0
 226      *    rather than 0,...,n-1; this is a cyclic permutation of
 227      *    the starting point and hence is odd iff n is even.)
 228      */
 229     parity = ((X(params, gap) - (params->w-1)) ^
 230               (Y(params, gap) - (params->h-1)) ^
 231               (n+1)) & 1;
 232
 233     /*
 234      * Try the last two tiles one way round. If that fails, swap
 235      * them.
 236      */
 237     tiles[x1] = p1;
 238     tiles[x2] = p2;
 239     if (perm_parity(tiles, n) != parity) {
 240         tiles[x1] = p2;
 241         tiles[x2] = p1;
 242         assert(perm_parity(tiles, n) == parity);
 243     }
 244
 245     /*
 246      * Now construct the game description, by describing the tile
 247      * array as a simple sequence of comma-separated integers.
 248      */
 249     ret = NULL;
 250     retlen = 0;
 251     for (i = 0; i < n; i++) {
 252         char buf[80];
 253         int k;
 254
 255         k = sprintf(buf, "%d,", tiles[i]);
 256
 257         ret = sresize(ret, retlen + k + 1, char);
 258         strcpy(ret + retlen, buf);
 259         retlen += k;
 260     }
 261     ret[retlen-1] = '\0';              /* delete last comma */
 262
 263     sfree(tiles);
 264     sfree(used);
 265
 266     return ret;
 267 }
 268
 269 static void game_free_aux_info(game_aux_info *aux)
 270 {
 271     assert(!"Shouldn't happen");
 272 }
 273
 274 static char *validate_desc(game_params *params, char *desc)
 275 {
 276     char *p, *err;
 277     int i, area;
 278     int *used;
 279
 280     area = params->w * params->h;
 281     p = desc;
 282     err = NULL;
 283
 284     used = snewn(area, int);
 285     for (i = 0; i < area; i++)
 286         used[i] = FALSE;
 287
 288     for (i = 0; i < area; i++) {
 289         char *q = p;
 290         int n;
 291
 292         if (*p < '0' || *p > '9') {
 293             err = "Not enough numbers in string";
 294             goto leave;
 295         }
 296         while (*p >= '0' && *p <= '9')
 297             p++;
 298         if (i < area-1 && *p != ',') {
 299             err = "Expected comma after number";
 300             goto leave;
 301         }
 302         else if (i == area-1 && *p) {
 303             err = "Excess junk at end of string";
 304             goto leave;
 305         }
 306         n = atoi(q);
 307         if (n < 0 || n >= area) {
 308             err = "Number out of range";
 309             goto leave;
 310         }
 311         if (used[n]) {
 312             err = "Number used twice";
 313             goto leave;
 314         }
 315         used[n] = TRUE;
 316
 317         if (*p) p++;                   /* eat comma */
 318     }
 319
 320     leave:
 321     sfree(used);
 322     return err;
 323 }
 324
 325 static game_state *new_game(game_params *params, char *desc)
 326 {
 327     game_state *state = snew(game_state);
 328     int i;
 329     char *p;
 330
 331     state->w = params->w;
 332     state->h = params->h;
 333     state->n = params->w * params->h;
 334     state->tiles = snewn(state->n, int);
 335
 336     state->gap_pos = 0;
 337     p = desc;
 338     i = 0;
 339     for (i = 0; i < state->n; i++) {
 340         assert(*p);
 341         state->tiles[i] = atoi(p);
 342         if (state->tiles[i] == 0)
 343             state->gap_pos = i;
 344         while (*p && *p != ',')
 345             p++;
 346         if (*p) p++;                   /* eat comma */
 347     }
 348     assert(!*p);
 349     assert(state->tiles[state->gap_pos] == 0);
 350
 351     state->completed = state->movecount = 0;
 352     state->used_solve = state->just_used_solve = FALSE;
 353
 354     return state;
 355 }
 356
 357 static game_state *dup_game(game_state *state)
 358 {
 359     game_state *ret = snew(game_state);
 360
 361     ret->w = state->w;
 362     ret->h = state->h;
 363     ret->n = state->n;
 364     ret->tiles = snewn(state->w * state->h, int);
 365     memcpy(ret->tiles, state->tiles, state->w * state->h * sizeof(int));
 366     ret->gap_pos = state->gap_pos;
 367     ret->completed = state->completed;
 368     ret->movecount = state->movecount;
 369     ret->used_solve = state->used_solve;
 370     ret->just_used_solve = state->just_used_solve;
 371
 372     return ret;
 373 }
 374
 375 static void free_game(game_state *state)
 376 {
 377     sfree(state);
 378 }
 379
 380 static game_state *solve_game(game_state *state, game_aux_info *aux,
 381                               char **error)
 382 {
 383     game_state *ret = dup_game(state);
 384     int i;
 385
 386     /*
 387      * Simply replace the grid with a solved one. For this game,
 388      * this isn't a useful operation for actually telling the user
 389      * what they should have done, but it is useful for
 390      * conveniently being able to get hold of a clean state from
 391      * which to practise manoeuvres.
 392      */
 393     for (i = 0; i < ret->n; i++)
 394         ret->tiles[i] = (i+1) % ret->n;
 395     ret->gap_pos = ret->n-1;
 396     ret->used_solve = ret->just_used_solve = TRUE;
 397     ret->completed = ret->movecount = 1;
 398
 399     return ret;
 400 }
 401
 402 static char *game_text_format(game_state *state)
 403 {
 404     char *ret, *p, buf[80];
 405     int x, y, col, maxlen;
 406
 407     /*
 408      * First work out how many characters we need to display each
 409      * number.
 410      */
 411     col = sprintf(buf, "%d", state->n-1);
 412
 413     /*
 414      * Now we know the exact total size of the grid we're going to
 415      * produce: it's got h rows, each containing w lots of col, w-1
 416      * spaces and a trailing newline.
 417      */
 418     maxlen = state->h * state->w * (col+1);
 419
 420     ret = snewn(maxlen+1, char);
 421     p = ret;
 422
 423     for (y = 0; y < state->h; y++) {
 424         for (x = 0; x < state->w; x++) {
 425             int v = state->tiles[state->w*y+x];
 426             if (v == 0)
 427                 sprintf(buf, "%*s", col, "");
 428             else
 429                 sprintf(buf, "%*d", col, v);
 430             memcpy(p, buf, col);
 431             p += col;
 432             if (x+1 == state->w)
 433                 *p++ = '\n';
 434             else
 435                 *p++ = ' ';
 436         }
 437     }
 438
 439     assert(p - ret == maxlen);
 440     *p = '\0';
 441     return ret;
 442 }
 443
 444 static game_ui *new_ui(game_state *state)
 445 {
 446     return NULL;
 447 }
 448
 449 static void free_ui(game_ui *ui)
 450 {
 451 }
 452
 453 static game_state *make_move(game_state *from, game_ui *ui,
 454                              int x, int y, int button)
 455 {
 456     int gx, gy, dx, dy, ux, uy, up, p;
 457     game_state *ret;
 458
 459     gx = X(from, from->gap_pos);
 460     gy = Y(from, from->gap_pos);
 461
 462     if (button == CURSOR_RIGHT && gx > 0)
 463         dx = gx - 1, dy = gy;
 464     else if (button == CURSOR_LEFT && gx < from->w-1)
 465         dx = gx + 1, dy = gy;
 466     else if (button == CURSOR_DOWN && gy > 0)
 467         dy = gy - 1, dx = gx;
 468     else if (button == CURSOR_UP && gy < from->h-1)
 469         dy = gy + 1, dx = gx;
 470     else if (button == LEFT_BUTTON) {
 471         dx = FROMCOORD(x);
 472         dy = FROMCOORD(y);
 473         if (dx < 0 || dx >= from->w || dy < 0 || dy >= from->h)
 474             return NULL;               /* out of bounds */
 475         /*
 476          * Any click location should be equal to the gap location
 477          * in _precisely_ one coordinate.
 478          */
 479         if ((dx == gx && dy == gy) || (dx != gx && dy != gy))
 480             return NULL;
 481     } else
 482         return NULL;                   /* no move */
 483
 484     /*
 485      * Find the unit displacement from the original gap
 486      * position towards this one.
 487      */
 488     ux = (dx < gx ? -1 : dx > gx ? +1 : 0);
 489     uy = (dy < gy ? -1 : dy > gy ? +1 : 0);
 490     up = C(from, ux, uy);
 491
 492     ret = dup_game(from);
 493     ret->just_used_solve = FALSE;      /* zero this in a hurry */
 494
 495     ret->gap_pos = C(from, dx, dy);
 496     assert(ret->gap_pos >= 0 && ret->gap_pos < ret->n);
 497
 498     ret->tiles[ret->gap_pos] = 0;
 499
 500     for (p = from->gap_pos; p != ret->gap_pos; p += up) {
 501         assert(p >= 0 && p < from->n);
 502         ret->tiles[p] = from->tiles[p + up];
 503         ret->movecount++;
 504     }
 505
 506     /*
 507      * See if the game has been completed.
 508      */
 509     if (!ret->completed) {
 510         ret->completed = ret->movecount;
 511         for (p = 0; p < ret->n; p++)
 512             if (ret->tiles[p] != (p < ret->n-1 ? p+1 : 0))
 513                 ret->completed = 0;
 514     }
 515
 516     return ret;
 517 }
 518
 519 /* ----------------------------------------------------------------------
 520  * Drawing routines.
 521  */
 522
 523 struct game_drawstate {
 524     int started;
 525     int w, h, bgcolour;
 526     int *tiles;
 527 };
 528
 529 static void game_size(game_params *params, int *x, int *y)
 530 {
 531     *x = TILE_SIZE * params->w + 2 * BORDER;
 532     *y = TILE_SIZE * params->h + 2 * BORDER;
 533 }
 534
 535 static float *game_colours(frontend *fe, game_state *state, int *ncolours)
 536 {
 537     float *ret = snewn(3 * NCOLOURS, float);
 538     int i;
 539     float max;
 540
 541     frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]);
 542
 543     /*
 544      * Drop the background colour so that the highlight is
 545      * noticeably brighter than it while still being under 1.
 546      */
 547     max = ret[COL_BACKGROUND*3];
 548     for (i = 1; i < 3; i++)
 549         if (ret[COL_BACKGROUND*3+i] > max)
 550             max = ret[COL_BACKGROUND*3+i];
 551     if (max * 1.2F > 1.0F) {
 552         for (i = 0; i < 3; i++)
 553             ret[COL_BACKGROUND*3+i] /= (max * 1.2F);
 554     }
 555
 556     for (i = 0; i < 3; i++) {
 557         ret[COL_HIGHLIGHT * 3 + i] = ret[COL_BACKGROUND * 3 + i] * 1.2F;
 558         ret[COL_LOWLIGHT * 3 + i] = ret[COL_BACKGROUND * 3 + i] * 0.8F;
 559         ret[COL_TEXT * 3 + i] = 0.0;
 560     }
 561
 562     *ncolours = NCOLOURS;
 563     return ret;
 564 }
 565
 566 static game_drawstate *game_new_drawstate(game_state *state)
 567 {
 568     struct game_drawstate *ds = snew(struct game_drawstate);
 569     int i;
 570
 571     ds->started = FALSE;
 572     ds->w = state->w;
 573     ds->h = state->h;
 574     ds->bgcolour = COL_BACKGROUND;
 575     ds->tiles = snewn(ds->w*ds->h, int);
 576     for (i = 0; i < ds->w*ds->h; i++)
 577         ds->tiles[i] = -1;
 578
 579     return ds;
 580 }
 581
 582 static void game_free_drawstate(game_drawstate *ds)
 583 {
 584     sfree(ds->tiles);
 585     sfree(ds);
 586 }
 587
 588 static void draw_tile(frontend *fe, game_state *state, int x, int y,
 589                       int tile, int flash_colour)
 590 {
 591     if (tile == 0) {
 592         draw_rect(fe, x, y, TILE_SIZE, TILE_SIZE,
 593                   flash_colour);
 594     } else {
 595         int coords[6];
 596         char str[40];
 597
 598         coords[0] = x + TILE_SIZE - 1;
 599         coords[1] = y + TILE_SIZE - 1;
 600         coords[2] = x + TILE_SIZE - 1;
 601         coords[3] = y;
 602         coords[4] = x;
 603         coords[5] = y + TILE_SIZE - 1;
 604         draw_polygon(fe, coords, 3, TRUE, COL_LOWLIGHT);
 605         draw_polygon(fe, coords, 3, FALSE, COL_LOWLIGHT);
 606
 607         coords[0] = x;
 608         coords[1] = y;
 609         draw_polygon(fe, coords, 3, TRUE, COL_HIGHLIGHT);
 610         draw_polygon(fe, coords, 3, FALSE, COL_HIGHLIGHT);
 611
 612         draw_rect(fe, x + HIGHLIGHT_WIDTH, y + HIGHLIGHT_WIDTH,
 613                   TILE_SIZE - 2*HIGHLIGHT_WIDTH, TILE_SIZE - 2*HIGHLIGHT_WIDTH,
 614                   flash_colour);
 615
 616         sprintf(str, "%d", tile);
 617         draw_text(fe, x + TILE_SIZE/2, y + TILE_SIZE/2,
 618                   FONT_VARIABLE, TILE_SIZE/3, ALIGN_VCENTRE | ALIGN_HCENTRE,
 619                   COL_TEXT, str);
 620     }
 621     draw_update(fe, x, y, TILE_SIZE, TILE_SIZE);
 622 }
 623
 624 static void game_redraw(frontend *fe, game_drawstate *ds, game_state *oldstate,
 625                  game_state *state, int dir, game_ui *ui,
 626                  float animtime, float flashtime)
 627 {
 628     int i, pass, bgcolour;
 629
 630     if (flashtime > 0) {
 631         int frame = (int)(flashtime / FLASH_FRAME);
 632         bgcolour = (frame % 2 ? COL_LOWLIGHT : COL_HIGHLIGHT);
 633     } else
 634         bgcolour = COL_BACKGROUND;
 635
 636     if (!ds->started) {
 637         int coords[6];
 638
 639         draw_rect(fe, 0, 0,
 640                   TILE_SIZE * state->w + 2 * BORDER,
 641                   TILE_SIZE * state->h + 2 * BORDER, COL_BACKGROUND);
 642         draw_update(fe, 0, 0,
 643                     TILE_SIZE * state->w + 2 * BORDER,
 644                     TILE_SIZE * state->h + 2 * BORDER);
 645
 646         /*
 647          * Recessed area containing the whole puzzle.
 648          */
 649         coords[0] = COORD(state->w) + HIGHLIGHT_WIDTH - 1;
 650         coords[1] = COORD(state->h) + HIGHLIGHT_WIDTH - 1;
 651         coords[2] = COORD(state->w) + HIGHLIGHT_WIDTH - 1;
 652         coords[3] = COORD(0) - HIGHLIGHT_WIDTH;
 653         coords[4] = COORD(0) - HIGHLIGHT_WIDTH;
 654         coords[5] = COORD(state->h) + HIGHLIGHT_WIDTH - 1;
 655         draw_polygon(fe, coords, 3, TRUE, COL_HIGHLIGHT);
 656         draw_polygon(fe, coords, 3, FALSE, COL_HIGHLIGHT);
 657
 658         coords[1] = COORD(0) - HIGHLIGHT_WIDTH;
 659         coords[0] = COORD(0) - HIGHLIGHT_WIDTH;
 660         draw_polygon(fe, coords, 3, TRUE, COL_LOWLIGHT);
 661         draw_polygon(fe, coords, 3, FALSE, COL_LOWLIGHT);
 662
 663         ds->started = TRUE;
 664     }
 665
 666     /*
 667      * Now draw each tile. We do this in two passes to make
 668      * animation easy.
 669      */
 670     for (pass = 0; pass < 2; pass++) {
 671         for (i = 0; i < state->n; i++) {
 672             int t, t0;
 673             /*
 674              * Figure out what should be displayed at this
 675              * location. It's either a simple tile, or it's a
 676              * transition between two tiles (in which case we say
 677              * -1 because it must always be drawn).
 678              */
 679
 680             if (oldstate && oldstate->tiles[i] != state->tiles[i])
 681                 t = -1;
 682             else
 683                 t = state->tiles[i];
 684
 685             t0 = t;
 686
 687             if (ds->bgcolour != bgcolour ||   /* always redraw when flashing */
 688                 ds->tiles[i] != t || ds->tiles[i] == -1 || t == -1) {
 689                 int x, y;
 690
 691                 /*
 692                  * Figure out what to _actually_ draw, and where to
 693                  * draw it.
 694                  */
 695                 if (t == -1) {
 696                     int x0, y0, x1, y1;
 697                     int j;
 698
 699                     /*
 700                      * On the first pass, just blank the tile.
 701                      */
 702                     if (pass == 0) {
 703                         x = COORD(X(state, i));
 704                         y = COORD(Y(state, i));
 705                         t = 0;
 706                     } else {
 707                         float c;
 708
 709                         t = state->tiles[i];
 710
 711                         /*
 712                          * Don't bother moving the gap; just don't
 713                          * draw it.
 714                          */
 715                         if (t == 0)
 716                             continue;
 717
 718                         /*
 719                          * Find the coordinates of this tile in the old and
 720                          * new states.
 721                          */
 722                         x1 = COORD(X(state, i));
 723                         y1 = COORD(Y(state, i));
 724                         for (j = 0; j < oldstate->n; j++)
 725                             if (oldstate->tiles[j] == state->tiles[i])
 726                                 break;
 727                         assert(j < oldstate->n);
 728                         x0 = COORD(X(state, j));
 729                         y0 = COORD(Y(state, j));
 730
 731                         c = (animtime / ANIM_TIME);
 732                         if (c < 0.0F) c = 0.0F;
 733                         if (c > 1.0F) c = 1.0F;
 734
 735                         x = x0 + (int)(c * (x1 - x0));
 736                         y = y0 + (int)(c * (y1 - y0));
 737                     }
 738
 739                 } else {
 740                     if (pass == 0)
 741                         continue;
 742                     x = COORD(X(state, i));
 743                     y = COORD(Y(state, i));
 744                 }
 745
 746                 draw_tile(fe, state, x, y, t, bgcolour);
 747             }
 748             ds->tiles[i] = t0;
 749         }
 750     }
 751     ds->bgcolour = bgcolour;
 752
 753     /*
 754      * Update the status bar.
 755      */
 756     {
 757         char statusbuf[256];
 758
 759         /*
 760          * Don't show the new status until we're also showing the
 761          * new _state_ - after the game animation is complete.
 762          */
 763         if (oldstate)
 764             state = oldstate;
 765
 766         if (state->used_solve)
 767             sprintf(statusbuf, "Moves since auto-solve: %d",
 768                     state->movecount - state->completed);
 769         else
 770             sprintf(statusbuf, "%sMoves: %d",
 771                     (state->completed ? "COMPLETED! " : ""),
 772                     (state->completed ? state->completed : state->movecount));
 773
 774         status_bar(fe, statusbuf);
 775     }
 776 }
 777
 778 static float game_anim_length(game_state *oldstate,
 779                               game_state *newstate, int dir)
 780 {
 781     if ((dir > 0 && newstate->just_used_solve) ||
 782         (dir < 0 && oldstate->just_used_solve))
 783         return 0.0F;
 784     else
 785         return ANIM_TIME;
 786 }
 787
 788 static float game_flash_length(game_state *oldstate,
 789                                game_state *newstate, int dir)
 790 {
 791     if (!oldstate->completed && newstate->completed &&
 792         !oldstate->used_solve && !newstate->used_solve)
 793         return 2 * FLASH_FRAME;
 794     else
 795         return 0.0F;
 796 }
 797
 798 static int game_wants_statusbar(void)
 799 {
 800     return TRUE;
 801 }
 802
 803 #ifdef COMBINED
 804 #define thegame fifteen
 805 #endif
 806
 807 const struct game thegame = {
 808     "Fifteen", "games.fifteen",
 809     default_params,
 810     game_fetch_preset,
 811     decode_params,
 812     encode_params,
 813     free_params,
 814     dup_params,
 815     TRUE, game_configure, custom_params,
 816     validate_params,
 817     new_game_desc,
 818     game_free_aux_info,
 819     validate_desc,
 820     new_game,
 821     dup_game,
 822     free_game,
 823     TRUE, solve_game,
 824     TRUE, game_text_format,
 825     new_ui,
 826     free_ui,
 827     make_move,
 828     game_size,
 829     game_colours,
 830     game_new_drawstate,
 831     game_free_drawstate,
 832     game_redraw,
 833     game_anim_length,
 834     game_flash_length,
 835     game_wants_statusbar,
 836 };