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 game_state *new_game(game_params *params, char *seed)
251 game_state *state = snew(game_state);
255 state->w = params->w;
256 state->h = params->h;
257 state->n = params->w * params->h;
258 state->tiles = snewn(state->n, int);
263 for (i = 0; i < state->n; i++) {
265 state->tiles[i] = atoi(p);
266 if (state->tiles[i] == 0)
268 while (*p && *p != ',')
270 if (*p) p++; /* eat comma */
273 assert(state->tiles[state->gap_pos] == 0);
275 state->completed = state->movecount = 0;
280 game_state *dup_game(game_state *state)
282 game_state *ret = snew(game_state);
287 ret->tiles = snewn(state->w * state->h, int);
288 memcpy(ret->tiles, state->tiles, state->w * state->h * sizeof(int));
289 ret->gap_pos = state->gap_pos;
290 ret->completed = state->completed;
291 ret->movecount = state->movecount;
296 void free_game(game_state *state)
301 game_state *make_move(game_state *from, int x, int y, int button)
303 int gx, gy, dx, dy, ux, uy, up, p;
306 gx = X(from, from->gap_pos);
307 gy = Y(from, from->gap_pos);
309 if (button == CURSOR_RIGHT && gx > 0)
310 dx = gx - 1, dy = gy;
311 else if (button == CURSOR_LEFT && gx < from->w-1)
312 dx = gx + 1, dy = gy;
313 else if (button == CURSOR_DOWN && gy > 0)
314 dy = gy - 1, dx = gx;
315 else if (button == CURSOR_UP && gy < from->h-1)
316 dy = gy + 1, dx = gx;
317 else if (button == LEFT_BUTTON) {
320 if (dx < 0 || dx >= from->w || dy < 0 || dy >= from->h)
321 return NULL; /* out of bounds */
323 * Any click location should be equal to the gap location
324 * in _precisely_ one coordinate.
326 if ((dx == gx && dy == gy) || (dx != gx && dy != gy))
329 return NULL; /* no move */
332 * Find the unit displacement from the original gap
333 * position towards this one.
335 ux = (dx < gx ? -1 : dx > gx ? +1 : 0);
336 uy = (dy < gy ? -1 : dy > gy ? +1 : 0);
337 up = C(from, ux, uy);
339 ret = dup_game(from);
341 ret->gap_pos = C(from, dx, dy);
342 assert(ret->gap_pos >= 0 && ret->gap_pos < ret->n);
344 ret->tiles[ret->gap_pos] = 0;
346 for (p = from->gap_pos; p != ret->gap_pos; p += up) {
347 assert(p >= 0 && p < from->n);
348 ret->tiles[p] = from->tiles[p + up];
353 * See if the game has been completed.
355 if (!ret->completed) {
356 ret->completed = ret->movecount;
357 for (p = 0; p < ret->n; p++)
358 if (ret->tiles[p] != (p < ret->n-1 ? p+1 : 0))
365 /* ----------------------------------------------------------------------
369 struct game_drawstate {
375 void game_size(game_params *params, int *x, int *y)
377 *x = TILE_SIZE * params->w + 2 * BORDER;
378 *y = TILE_SIZE * params->h + 2 * BORDER;
381 float *game_colours(frontend *fe, game_state *state, int *ncolours)
383 float *ret = snewn(3 * NCOLOURS, float);
387 frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]);
390 * Drop the background colour so that the highlight is
391 * noticeably brighter than it while still being under 1.
393 max = ret[COL_BACKGROUND*3];
394 for (i = 1; i < 3; i++)
395 if (ret[COL_BACKGROUND*3+i] > max)
396 max = ret[COL_BACKGROUND*3+i];
397 if (max * 1.2F > 1.0F) {
398 for (i = 0; i < 3; i++)
399 ret[COL_BACKGROUND*3+i] /= (max * 1.2F);
402 for (i = 0; i < 3; i++) {
403 ret[COL_HIGHLIGHT * 3 + i] = ret[COL_BACKGROUND * 3 + i] * 1.2F;
404 ret[COL_LOWLIGHT * 3 + i] = ret[COL_BACKGROUND * 3 + i] * 0.8F;
405 ret[COL_TEXT * 3 + i] = 0.0;
408 *ncolours = NCOLOURS;
412 game_drawstate *game_new_drawstate(game_state *state)
414 struct game_drawstate *ds = snew(struct game_drawstate);
420 ds->bgcolour = COL_BACKGROUND;
421 ds->tiles = snewn(ds->w*ds->h, int);
422 for (i = 0; i < ds->w*ds->h; i++)
428 void game_free_drawstate(game_drawstate *ds)
434 static void draw_tile(frontend *fe, game_state *state, int x, int y,
435 int tile, int flash_colour)
438 draw_rect(fe, x, y, TILE_SIZE, TILE_SIZE,
444 coords[0] = x + TILE_SIZE - 1;
445 coords[1] = y + TILE_SIZE - 1;
446 coords[2] = x + TILE_SIZE - 1;
449 coords[5] = y + TILE_SIZE - 1;
450 draw_polygon(fe, coords, 3, TRUE, COL_LOWLIGHT);
451 draw_polygon(fe, coords, 3, FALSE, COL_LOWLIGHT);
455 draw_polygon(fe, coords, 3, TRUE, COL_HIGHLIGHT);
456 draw_polygon(fe, coords, 3, FALSE, COL_HIGHLIGHT);
458 draw_rect(fe, x + HIGHLIGHT_WIDTH, y + HIGHLIGHT_WIDTH,
459 TILE_SIZE - 2*HIGHLIGHT_WIDTH, TILE_SIZE - 2*HIGHLIGHT_WIDTH,
462 sprintf(str, "%d", tile);
463 draw_text(fe, x + TILE_SIZE/2, y + TILE_SIZE/2,
464 FONT_VARIABLE, TILE_SIZE/3, ALIGN_VCENTRE | ALIGN_HCENTRE,
467 draw_update(fe, x, y, TILE_SIZE, TILE_SIZE);
470 void game_redraw(frontend *fe, game_drawstate *ds, game_state *oldstate,
471 game_state *state, float animtime, float flashtime)
473 int i, pass, bgcolour;
476 int frame = (int)(flashtime / FLASH_FRAME);
477 bgcolour = (frame % 2 ? COL_LOWLIGHT : COL_HIGHLIGHT);
479 bgcolour = COL_BACKGROUND;
485 TILE_SIZE * state->w + 2 * BORDER,
486 TILE_SIZE * state->h + 2 * BORDER, COL_BACKGROUND);
487 draw_update(fe, 0, 0,
488 TILE_SIZE * state->w + 2 * BORDER,
489 TILE_SIZE * state->h + 2 * BORDER);
492 * Recessed area containing the whole puzzle.
494 coords[0] = COORD(state->w) + HIGHLIGHT_WIDTH - 1;
495 coords[1] = COORD(state->h) + HIGHLIGHT_WIDTH - 1;
496 coords[2] = COORD(state->w) + HIGHLIGHT_WIDTH - 1;
497 coords[3] = COORD(0) - HIGHLIGHT_WIDTH;
498 coords[4] = COORD(0) - HIGHLIGHT_WIDTH;
499 coords[5] = COORD(state->h) + HIGHLIGHT_WIDTH - 1;
500 draw_polygon(fe, coords, 3, TRUE, COL_HIGHLIGHT);
501 draw_polygon(fe, coords, 3, FALSE, COL_HIGHLIGHT);
503 coords[1] = COORD(0) - HIGHLIGHT_WIDTH;
504 coords[0] = COORD(0) - HIGHLIGHT_WIDTH;
505 draw_polygon(fe, coords, 3, TRUE, COL_LOWLIGHT);
506 draw_polygon(fe, coords, 3, FALSE, COL_LOWLIGHT);
512 * Now draw each tile. We do this in two passes to make
515 for (pass = 0; pass < 2; pass++) {
516 for (i = 0; i < state->n; i++) {
519 * Figure out what should be displayed at this
520 * location. It's either a simple tile, or it's a
521 * transition between two tiles (in which case we say
522 * -1 because it must always be drawn).
525 if (oldstate && oldstate->tiles[i] != state->tiles[i])
532 if (ds->bgcolour != bgcolour || /* always redraw when flashing */
533 ds->tiles[i] != t || ds->tiles[i] == -1 || t == -1) {
537 * Figure out what to _actually_ draw, and where to
545 * On the first pass, just blank the tile.
548 x = COORD(X(state, i));
549 y = COORD(Y(state, i));
557 * Don't bother moving the gap; just don't
564 * Find the coordinates of this tile in the old and
567 x1 = COORD(X(state, i));
568 y1 = COORD(Y(state, i));
569 for (j = 0; j < oldstate->n; j++)
570 if (oldstate->tiles[j] == state->tiles[i])
572 assert(j < oldstate->n);
573 x0 = COORD(X(state, j));
574 y0 = COORD(Y(state, j));
576 c = (animtime / ANIM_TIME);
577 if (c < 0.0F) c = 0.0F;
578 if (c > 1.0F) c = 1.0F;
580 x = x0 + (int)(c * (x1 - x0));
581 y = y0 + (int)(c * (y1 - y0));
587 x = COORD(X(state, i));
588 y = COORD(Y(state, i));
591 draw_tile(fe, state, x, y, t, bgcolour);
596 ds->bgcolour = bgcolour;
599 * Update the status bar.
605 * Don't show the new status until we're also showing the
606 * new _state_ - after the game animation is complete.
611 sprintf(statusbuf, "%sMoves: %d",
612 (state->completed ? "COMPLETED! " : ""),
613 (state->completed ? state->completed : state->movecount));
615 status_bar(fe, statusbuf);
619 float game_anim_length(game_state *oldstate, game_state *newstate)
624 float game_flash_length(game_state *oldstate, game_state *newstate)
626 if (!oldstate->completed && newstate->completed)
627 return 2 * FLASH_FRAME;
632 int game_wants_statusbar(void)