2 * fifteen.c: standard 15-puzzle.
13 const char *const game_name = "Fifteen";
16 #define BORDER (TILE_SIZE / 2)
17 #define HIGHLIGHT_WIDTH (TILE_SIZE / 20)
18 #define COORD(x) ( (x) * TILE_SIZE + BORDER )
19 #define FROMCOORD(x) ( ((x) - BORDER + TILE_SIZE) / TILE_SIZE - 1 )
21 #define ANIM_TIME 0.1F
22 #define FLASH_FRAME 0.1F
24 #define X(state, i) ( (i) % (state)->w )
25 #define Y(state, i) ( (i) / (state)->w )
26 #define C(state, x, y) ( (y) * (state)->w + (x) )
48 game_params *default_params(void)
50 game_params *ret = snew(game_params);
57 int game_fetch_preset(int i, char **name, game_params **params)
62 void free_params(game_params *params)
67 game_params *dup_params(game_params *params)
69 game_params *ret = snew(game_params);
70 *ret = *params; /* structure copy */
74 int perm_parity(int *perm, int n)
80 for (i = 0; i < n-1; i++)
81 for (j = i+1; j < n; j++)
82 if (perm[i] > perm[j])
88 char *new_game_seed(game_params *params)
91 int x1, x2, p1, p2, parity;
96 n = params->w * params->h;
98 tiles = snewn(n, int);
101 for (i = 0; i < n; i++) {
111 * Place everything else except the last two tiles.
113 for (x = 0, i = n-1; i > 2; i--) {
114 int k = rand_upto(i);
117 for (j = 0; j < n; j++)
118 if (!used[j] && (k-- == 0))
121 assert(j < n && !used[j]);
124 while (tiles[x] >= 0)
131 * Find the last two locations, and the last two pieces.
133 while (tiles[x] >= 0)
138 while (tiles[x] >= 0)
143 for (i = 0; i < n; i++)
147 for (i = p1+1; i < n; i++)
153 * Determine the required parity of the overall permutation.
154 * This is the XOR of:
156 * - The chessboard parity ((x^y)&1) of the gap square. The
157 * bottom right, and therefore also the top left, count as
160 * - The parity of n. (The target permutation is 1,...,n-1,0
161 * rather than 0,...,n-1; this is a cyclic permutation of
162 * the starting point and hence is odd iff n is even.)
164 parity = (X(params, gap) ^ Y(params, gap) ^ (n+1)) & 1;
167 * Try the last two tiles one way round. If that fails, swap
172 if (perm_parity(tiles, n) != parity) {
175 assert(perm_parity(tiles, n) == parity);
179 * Now construct the game seed, by describing the tile array as
180 * a simple sequence of comma-separated integers.
184 for (i = 0; i < n; i++) {
188 k = sprintf(buf, "%d,", tiles[i]);
190 ret = sresize(ret, retlen + k + 1, char);
191 strcpy(ret + retlen, buf);
194 ret[retlen-1] = '\0'; /* delete last comma */
202 game_state *new_game(game_params *params, char *seed)
204 game_state *state = snew(game_state);
208 state->w = params->w;
209 state->h = params->h;
210 state->n = params->w * params->h;
211 state->tiles = snewn(state->n, int);
216 for (i = 0; i < state->n; i++) {
218 state->tiles[i] = atoi(p);
219 if (state->tiles[i] == 0)
221 while (*p && *p != ',')
223 if (*p) p++; /* eat comma */
226 assert(state->tiles[state->gap_pos] == 0);
228 state->completed = state->movecount = 0;
233 game_state *dup_game(game_state *state)
235 game_state *ret = snew(game_state);
240 ret->tiles = snewn(state->w * state->h, int);
241 memcpy(ret->tiles, state->tiles, state->w * state->h * sizeof(int));
242 ret->gap_pos = state->gap_pos;
243 ret->completed = state->completed;
244 ret->movecount = state->movecount;
249 void free_game(game_state *state)
254 game_state *make_move(game_state *from, int x, int y, int button)
256 int gx, gy, dx, dy, ux, uy, up, p;
259 gx = X(from, from->gap_pos);
260 gy = Y(from, from->gap_pos);
262 if (button == CURSOR_RIGHT && gx > 0)
263 dx = gx - 1, dy = gy;
264 else if (button == CURSOR_LEFT && gx < from->w-1)
265 dx = gx + 1, dy = gy;
266 else if (button == CURSOR_DOWN && gy > 0)
267 dy = gy - 1, dx = gx;
268 else if (button == CURSOR_UP && gy < from->h-1)
269 dy = gy + 1, dx = gx;
270 else if (button == LEFT_BUTTON) {
273 if (dx < 0 || dx >= from->w || dy < 0 || dy >= from->h)
274 return NULL; /* out of bounds */
276 * Any click location should be equal to the gap location
277 * in _precisely_ one coordinate.
279 if ((dx == gx && dy == gy) || (dx != gx && dy != gy))
282 return NULL; /* no move */
285 * Find the unit displacement from the original gap
286 * position towards this one.
288 ux = (dx < gx ? -1 : dx > gx ? +1 : 0);
289 uy = (dy < gy ? -1 : dy > gy ? +1 : 0);
290 up = C(from, ux, uy);
292 ret = dup_game(from);
294 ret->gap_pos = C(from, dx, dy);
295 assert(ret->gap_pos >= 0 && ret->gap_pos < ret->n);
297 ret->tiles[ret->gap_pos] = 0;
299 for (p = from->gap_pos; p != ret->gap_pos; p += up) {
300 assert(p >= 0 && p < from->n);
301 ret->tiles[p] = from->tiles[p + up];
306 * See if the game has been completed.
308 if (!ret->completed) {
309 ret->completed = ret->movecount;
310 for (p = 0; p < ret->n; p++)
311 if (ret->tiles[p] != (p < ret->n-1 ? p+1 : 0))
318 /* ----------------------------------------------------------------------
322 struct game_drawstate {
328 void game_size(game_params *params, int *x, int *y)
330 *x = TILE_SIZE * params->w + 2 * BORDER;
331 *y = TILE_SIZE * params->h + 2 * BORDER;
334 float *game_colours(frontend *fe, game_state *state, int *ncolours)
336 float *ret = snewn(3 * NCOLOURS, float);
340 frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]);
343 * Drop the background colour so that the highlight is
344 * noticeably brighter than it while still being under 1.
346 max = ret[COL_BACKGROUND*3];
347 for (i = 1; i < 3; i++)
348 if (ret[COL_BACKGROUND*3+i] > max)
349 max = ret[COL_BACKGROUND*3+i];
350 if (max * 1.2F > 1.0F) {
351 for (i = 0; i < 3; i++)
352 ret[COL_BACKGROUND*3+i] /= (max * 1.2F);
355 for (i = 0; i < 3; i++) {
356 ret[COL_HIGHLIGHT * 3 + i] = ret[COL_BACKGROUND * 3 + i] * 1.2F;
357 ret[COL_LOWLIGHT * 3 + i] = ret[COL_BACKGROUND * 3 + i] * 0.8F;
358 ret[COL_TEXT * 3 + i] = 0.0;
361 *ncolours = NCOLOURS;
365 game_drawstate *game_new_drawstate(game_state *state)
367 struct game_drawstate *ds = snew(struct game_drawstate);
373 ds->bgcolour = COL_BACKGROUND;
374 ds->tiles = snewn(ds->w*ds->h, int);
375 for (i = 0; i < ds->w*ds->h; i++)
381 void game_free_drawstate(game_drawstate *ds)
387 static void draw_tile(frontend *fe, game_state *state, int x, int y,
388 int tile, int flash_colour)
391 draw_rect(fe, x, y, TILE_SIZE, TILE_SIZE,
397 coords[0] = x + TILE_SIZE - 1;
398 coords[1] = y + TILE_SIZE - 1;
399 coords[2] = x + TILE_SIZE - 1;
402 coords[5] = y + TILE_SIZE - 1;
403 draw_polygon(fe, coords, 3, TRUE, COL_LOWLIGHT);
404 draw_polygon(fe, coords, 3, FALSE, COL_LOWLIGHT);
408 draw_polygon(fe, coords, 3, TRUE, COL_HIGHLIGHT);
409 draw_polygon(fe, coords, 3, FALSE, COL_HIGHLIGHT);
411 draw_rect(fe, x + HIGHLIGHT_WIDTH, y + HIGHLIGHT_WIDTH,
412 TILE_SIZE - 2*HIGHLIGHT_WIDTH, TILE_SIZE - 2*HIGHLIGHT_WIDTH,
415 sprintf(str, "%d", tile);
416 draw_text(fe, x + TILE_SIZE/2, y + TILE_SIZE/2,
417 FONT_VARIABLE, TILE_SIZE/3, ALIGN_VCENTRE | ALIGN_HCENTRE,
420 draw_update(fe, x, y, TILE_SIZE, TILE_SIZE);
423 void game_redraw(frontend *fe, game_drawstate *ds, game_state *oldstate,
424 game_state *state, float animtime, float flashtime)
426 int i, pass, bgcolour;
429 int frame = (int)(flashtime / FLASH_FRAME);
430 bgcolour = (frame % 2 ? COL_LOWLIGHT : COL_HIGHLIGHT);
432 bgcolour = COL_BACKGROUND;
438 TILE_SIZE * state->w + 2 * BORDER,
439 TILE_SIZE * state->h + 2 * BORDER, COL_BACKGROUND);
440 draw_update(fe, 0, 0,
441 TILE_SIZE * state->w + 2 * BORDER,
442 TILE_SIZE * state->h + 2 * BORDER);
445 * Recessed area containing the whole puzzle.
447 coords[0] = COORD(state->w) + HIGHLIGHT_WIDTH - 1;
448 coords[1] = COORD(state->h) + HIGHLIGHT_WIDTH - 1;
449 coords[2] = COORD(state->w) + HIGHLIGHT_WIDTH - 1;
450 coords[3] = COORD(0) - HIGHLIGHT_WIDTH;
451 coords[4] = COORD(0) - HIGHLIGHT_WIDTH;
452 coords[5] = COORD(state->h) + HIGHLIGHT_WIDTH - 1;
453 draw_polygon(fe, coords, 3, TRUE, COL_HIGHLIGHT);
454 draw_polygon(fe, coords, 3, FALSE, COL_HIGHLIGHT);
456 coords[1] = COORD(0) - HIGHLIGHT_WIDTH;
457 coords[0] = COORD(0) - HIGHLIGHT_WIDTH;
458 draw_polygon(fe, coords, 3, TRUE, COL_LOWLIGHT);
459 draw_polygon(fe, coords, 3, FALSE, COL_LOWLIGHT);
465 * Now draw each tile. We do this in two passes to make
468 for (pass = 0; pass < 2; pass++) {
469 for (i = 0; i < state->n; i++) {
472 * Figure out what should be displayed at this
473 * location. It's either a simple tile, or it's a
474 * transition between two tiles (in which case we say
475 * -1 because it must always be drawn).
478 if (oldstate && oldstate->tiles[i] != state->tiles[i])
485 if (ds->bgcolour != bgcolour || /* always redraw when flashing */
486 ds->tiles[i] != t || ds->tiles[i] == -1 || t == -1) {
490 * Figure out what to _actually_ draw, and where to
498 * On the first pass, just blank the tile.
501 x = COORD(X(state, i));
502 y = COORD(Y(state, i));
510 * Don't bother moving the gap; just don't
517 * Find the coordinates of this tile in the old and
520 x1 = COORD(X(state, i));
521 y1 = COORD(Y(state, i));
522 for (j = 0; j < oldstate->n; j++)
523 if (oldstate->tiles[j] == state->tiles[i])
525 assert(j < oldstate->n);
526 x0 = COORD(X(state, j));
527 y0 = COORD(Y(state, j));
529 c = (animtime / ANIM_TIME);
530 if (c < 0.0F) c = 0.0F;
531 if (c > 1.0F) c = 1.0F;
533 x = x0 + (int)(c * (x1 - x0));
534 y = y0 + (int)(c * (y1 - y0));
540 x = COORD(X(state, i));
541 y = COORD(Y(state, i));
544 draw_tile(fe, state, x, y, t, bgcolour);
549 ds->bgcolour = bgcolour;
552 * Update the status bar.
558 * Don't show the new status until we're also showing the
559 * new _state_ - after the game animation is complete.
564 sprintf(statusbuf, "%sMoves: %d",
565 (state->completed ? "COMPLETED! " : ""),
566 (state->completed ? state->completed : state->movecount));
568 status_bar(fe, statusbuf);
572 float game_anim_length(game_state *oldstate, game_state *newstate)
577 float game_flash_length(game_state *oldstate, game_state *newstate)
579 if (!oldstate->completed && newstate->completed)
580 return 2 * FLASH_FRAME;
585 int game_wants_statusbar(void)