2 * fifteen.c: standard 15-puzzle.
13 const char *const game_name = "Fifteen";
14 const int game_can_configure = TRUE;
17 #define BORDER (TILE_SIZE / 2)
18 #define HIGHLIGHT_WIDTH (TILE_SIZE / 20)
19 #define COORD(x) ( (x) * TILE_SIZE + BORDER )
20 #define FROMCOORD(x) ( ((x) - BORDER + TILE_SIZE) / TILE_SIZE - 1 )
22 #define ANIM_TIME 0.1F
23 #define FLASH_FRAME 0.1F
25 #define X(state, i) ( (i) % (state)->w )
26 #define Y(state, i) ( (i) / (state)->w )
27 #define C(state, x, y) ( (y) * (state)->w + (x) )
49 game_params *default_params(void)
51 game_params *ret = snew(game_params);
58 int game_fetch_preset(int i, char **name, game_params **params)
63 void free_params(game_params *params)
68 game_params *dup_params(game_params *params)
70 game_params *ret = snew(game_params);
71 *ret = *params; /* structure copy */
75 config_item *game_configure(game_params *params)
80 ret = snewn(3, config_item);
82 ret[0].name = "Width";
83 ret[0].type = C_STRING;
84 sprintf(buf, "%d", params->w);
85 ret[0].sval = dupstr(buf);
88 ret[1].name = "Height";
89 ret[1].type = C_STRING;
90 sprintf(buf, "%d", params->h);
91 ret[1].sval = dupstr(buf);
102 game_params *custom_params(config_item *cfg)
104 game_params *ret = snew(game_params);
106 ret->w = atoi(cfg[0].sval);
107 ret->h = atoi(cfg[1].sval);
112 char *validate_params(game_params *params)
114 if (params->w < 2 && params->h < 2)
115 return "Width and height must both be at least two";
120 int perm_parity(int *perm, int n)
126 for (i = 0; i < n-1; i++)
127 for (j = i+1; j < n; j++)
128 if (perm[i] > perm[j])
134 char *new_game_seed(game_params *params)
137 int x1, x2, p1, p2, parity;
142 n = params->w * params->h;
144 tiles = snewn(n, int);
145 used = snewn(n, int);
147 for (i = 0; i < n; i++) {
157 * Place everything else except the last two tiles.
159 for (x = 0, i = n-1; i > 2; i--) {
160 int k = rand_upto(i);
163 for (j = 0; j < n; j++)
164 if (!used[j] && (k-- == 0))
167 assert(j < n && !used[j]);
170 while (tiles[x] >= 0)
177 * Find the last two locations, and the last two pieces.
179 while (tiles[x] >= 0)
184 while (tiles[x] >= 0)
189 for (i = 0; i < n; i++)
193 for (i = p1+1; i < n; i++)
199 * Determine the required parity of the overall permutation.
200 * This is the XOR of:
202 * - The chessboard parity ((x^y)&1) of the gap square. The
203 * bottom right counts as even.
205 * - The parity of n. (The target permutation is 1,...,n-1,0
206 * rather than 0,...,n-1; this is a cyclic permutation of
207 * the starting point and hence is odd iff n is even.)
209 parity = ((X(params, gap) - (params->w-1)) ^
210 (Y(params, gap) - (params->h-1)) ^
214 * Try the last two tiles one way round. If that fails, swap
219 if (perm_parity(tiles, n) != parity) {
222 assert(perm_parity(tiles, n) == parity);
226 * Now construct the game seed, by describing the tile array as
227 * a simple sequence of comma-separated integers.
231 for (i = 0; i < n; i++) {
235 k = sprintf(buf, "%d,", tiles[i]);
237 ret = sresize(ret, retlen + k + 1, char);
238 strcpy(ret + retlen, buf);
241 ret[retlen-1] = '\0'; /* delete last comma */
249 char *validate_seed(game_params *params, char *seed)
255 area = params->w * params->h;
259 used = snewn(area, int);
260 for (i = 0; i < area; i++)
263 for (i = 0; i < area; i++) {
267 if (*p < '0' || *p > '9') {
268 err = "Not enough numbers in string";
271 while (*p >= '0' && *p <= '9')
273 if (i < area-1 && *p != ',') {
274 err = "Expected comma after number";
277 else if (i == area-1 && *p) {
278 err = "Excess junk at end of string";
282 if (n < 0 || n >= area) {
283 err = "Number out of range";
287 err = "Number used twice";
292 if (*p) p++; /* eat comma */
300 game_state *new_game(game_params *params, char *seed)
302 game_state *state = snew(game_state);
306 state->w = params->w;
307 state->h = params->h;
308 state->n = params->w * params->h;
309 state->tiles = snewn(state->n, int);
314 for (i = 0; i < state->n; i++) {
316 state->tiles[i] = atoi(p);
317 if (state->tiles[i] == 0)
319 while (*p && *p != ',')
321 if (*p) p++; /* eat comma */
324 assert(state->tiles[state->gap_pos] == 0);
326 state->completed = state->movecount = 0;
331 game_state *dup_game(game_state *state)
333 game_state *ret = snew(game_state);
338 ret->tiles = snewn(state->w * state->h, int);
339 memcpy(ret->tiles, state->tiles, state->w * state->h * sizeof(int));
340 ret->gap_pos = state->gap_pos;
341 ret->completed = state->completed;
342 ret->movecount = state->movecount;
347 void free_game(game_state *state)
352 game_state *make_move(game_state *from, int x, int y, int button)
354 int gx, gy, dx, dy, ux, uy, up, p;
357 gx = X(from, from->gap_pos);
358 gy = Y(from, from->gap_pos);
360 if (button == CURSOR_RIGHT && gx > 0)
361 dx = gx - 1, dy = gy;
362 else if (button == CURSOR_LEFT && gx < from->w-1)
363 dx = gx + 1, dy = gy;
364 else if (button == CURSOR_DOWN && gy > 0)
365 dy = gy - 1, dx = gx;
366 else if (button == CURSOR_UP && gy < from->h-1)
367 dy = gy + 1, dx = gx;
368 else if (button == LEFT_BUTTON) {
371 if (dx < 0 || dx >= from->w || dy < 0 || dy >= from->h)
372 return NULL; /* out of bounds */
374 * Any click location should be equal to the gap location
375 * in _precisely_ one coordinate.
377 if ((dx == gx && dy == gy) || (dx != gx && dy != gy))
380 return NULL; /* no move */
383 * Find the unit displacement from the original gap
384 * position towards this one.
386 ux = (dx < gx ? -1 : dx > gx ? +1 : 0);
387 uy = (dy < gy ? -1 : dy > gy ? +1 : 0);
388 up = C(from, ux, uy);
390 ret = dup_game(from);
392 ret->gap_pos = C(from, dx, dy);
393 assert(ret->gap_pos >= 0 && ret->gap_pos < ret->n);
395 ret->tiles[ret->gap_pos] = 0;
397 for (p = from->gap_pos; p != ret->gap_pos; p += up) {
398 assert(p >= 0 && p < from->n);
399 ret->tiles[p] = from->tiles[p + up];
404 * See if the game has been completed.
406 if (!ret->completed) {
407 ret->completed = ret->movecount;
408 for (p = 0; p < ret->n; p++)
409 if (ret->tiles[p] != (p < ret->n-1 ? p+1 : 0))
416 /* ----------------------------------------------------------------------
420 struct game_drawstate {
426 void game_size(game_params *params, int *x, int *y)
428 *x = TILE_SIZE * params->w + 2 * BORDER;
429 *y = TILE_SIZE * params->h + 2 * BORDER;
432 float *game_colours(frontend *fe, game_state *state, int *ncolours)
434 float *ret = snewn(3 * NCOLOURS, float);
438 frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]);
441 * Drop the background colour so that the highlight is
442 * noticeably brighter than it while still being under 1.
444 max = ret[COL_BACKGROUND*3];
445 for (i = 1; i < 3; i++)
446 if (ret[COL_BACKGROUND*3+i] > max)
447 max = ret[COL_BACKGROUND*3+i];
448 if (max * 1.2F > 1.0F) {
449 for (i = 0; i < 3; i++)
450 ret[COL_BACKGROUND*3+i] /= (max * 1.2F);
453 for (i = 0; i < 3; i++) {
454 ret[COL_HIGHLIGHT * 3 + i] = ret[COL_BACKGROUND * 3 + i] * 1.2F;
455 ret[COL_LOWLIGHT * 3 + i] = ret[COL_BACKGROUND * 3 + i] * 0.8F;
456 ret[COL_TEXT * 3 + i] = 0.0;
459 *ncolours = NCOLOURS;
463 game_drawstate *game_new_drawstate(game_state *state)
465 struct game_drawstate *ds = snew(struct game_drawstate);
471 ds->bgcolour = COL_BACKGROUND;
472 ds->tiles = snewn(ds->w*ds->h, int);
473 for (i = 0; i < ds->w*ds->h; i++)
479 void game_free_drawstate(game_drawstate *ds)
485 static void draw_tile(frontend *fe, game_state *state, int x, int y,
486 int tile, int flash_colour)
489 draw_rect(fe, x, y, TILE_SIZE, TILE_SIZE,
495 coords[0] = x + TILE_SIZE - 1;
496 coords[1] = y + TILE_SIZE - 1;
497 coords[2] = x + TILE_SIZE - 1;
500 coords[5] = y + TILE_SIZE - 1;
501 draw_polygon(fe, coords, 3, TRUE, COL_LOWLIGHT);
502 draw_polygon(fe, coords, 3, FALSE, COL_LOWLIGHT);
506 draw_polygon(fe, coords, 3, TRUE, COL_HIGHLIGHT);
507 draw_polygon(fe, coords, 3, FALSE, COL_HIGHLIGHT);
509 draw_rect(fe, x + HIGHLIGHT_WIDTH, y + HIGHLIGHT_WIDTH,
510 TILE_SIZE - 2*HIGHLIGHT_WIDTH, TILE_SIZE - 2*HIGHLIGHT_WIDTH,
513 sprintf(str, "%d", tile);
514 draw_text(fe, x + TILE_SIZE/2, y + TILE_SIZE/2,
515 FONT_VARIABLE, TILE_SIZE/3, ALIGN_VCENTRE | ALIGN_HCENTRE,
518 draw_update(fe, x, y, TILE_SIZE, TILE_SIZE);
521 void game_redraw(frontend *fe, game_drawstate *ds, game_state *oldstate,
522 game_state *state, float animtime, float flashtime)
524 int i, pass, bgcolour;
527 int frame = (int)(flashtime / FLASH_FRAME);
528 bgcolour = (frame % 2 ? COL_LOWLIGHT : COL_HIGHLIGHT);
530 bgcolour = COL_BACKGROUND;
536 TILE_SIZE * state->w + 2 * BORDER,
537 TILE_SIZE * state->h + 2 * BORDER, COL_BACKGROUND);
538 draw_update(fe, 0, 0,
539 TILE_SIZE * state->w + 2 * BORDER,
540 TILE_SIZE * state->h + 2 * BORDER);
543 * Recessed area containing the whole puzzle.
545 coords[0] = COORD(state->w) + HIGHLIGHT_WIDTH - 1;
546 coords[1] = COORD(state->h) + HIGHLIGHT_WIDTH - 1;
547 coords[2] = COORD(state->w) + HIGHLIGHT_WIDTH - 1;
548 coords[3] = COORD(0) - HIGHLIGHT_WIDTH;
549 coords[4] = COORD(0) - HIGHLIGHT_WIDTH;
550 coords[5] = COORD(state->h) + HIGHLIGHT_WIDTH - 1;
551 draw_polygon(fe, coords, 3, TRUE, COL_HIGHLIGHT);
552 draw_polygon(fe, coords, 3, FALSE, COL_HIGHLIGHT);
554 coords[1] = COORD(0) - HIGHLIGHT_WIDTH;
555 coords[0] = COORD(0) - HIGHLIGHT_WIDTH;
556 draw_polygon(fe, coords, 3, TRUE, COL_LOWLIGHT);
557 draw_polygon(fe, coords, 3, FALSE, COL_LOWLIGHT);
563 * Now draw each tile. We do this in two passes to make
566 for (pass = 0; pass < 2; pass++) {
567 for (i = 0; i < state->n; i++) {
570 * Figure out what should be displayed at this
571 * location. It's either a simple tile, or it's a
572 * transition between two tiles (in which case we say
573 * -1 because it must always be drawn).
576 if (oldstate && oldstate->tiles[i] != state->tiles[i])
583 if (ds->bgcolour != bgcolour || /* always redraw when flashing */
584 ds->tiles[i] != t || ds->tiles[i] == -1 || t == -1) {
588 * Figure out what to _actually_ draw, and where to
596 * On the first pass, just blank the tile.
599 x = COORD(X(state, i));
600 y = COORD(Y(state, i));
608 * Don't bother moving the gap; just don't
615 * Find the coordinates of this tile in the old and
618 x1 = COORD(X(state, i));
619 y1 = COORD(Y(state, i));
620 for (j = 0; j < oldstate->n; j++)
621 if (oldstate->tiles[j] == state->tiles[i])
623 assert(j < oldstate->n);
624 x0 = COORD(X(state, j));
625 y0 = COORD(Y(state, j));
627 c = (animtime / ANIM_TIME);
628 if (c < 0.0F) c = 0.0F;
629 if (c > 1.0F) c = 1.0F;
631 x = x0 + (int)(c * (x1 - x0));
632 y = y0 + (int)(c * (y1 - y0));
638 x = COORD(X(state, i));
639 y = COORD(Y(state, i));
642 draw_tile(fe, state, x, y, t, bgcolour);
647 ds->bgcolour = bgcolour;
650 * Update the status bar.
656 * Don't show the new status until we're also showing the
657 * new _state_ - after the game animation is complete.
662 sprintf(statusbuf, "%sMoves: %d",
663 (state->completed ? "COMPLETED! " : ""),
664 (state->completed ? state->completed : state->movecount));
666 status_bar(fe, statusbuf);
670 float game_anim_length(game_state *oldstate, game_state *newstate)
675 float game_flash_length(game_state *oldstate, game_state *newstate)
677 if (!oldstate->completed && newstate->completed)
678 return 2 * FLASH_FRAME;
683 int game_wants_statusbar(void)