e7414d31 |
1 | /* |
2 | * range.c: implementation of the Nikoli game 'Kurodoko' / 'Kuromasu'. |
3 | */ |
4 | |
5 | /* |
6 | * Puzzle rules: the player is given a WxH grid of white squares, some |
7 | * of which contain numbers. The goal is to paint some of the squares |
8 | * black, such that: |
9 | * |
10 | * - no cell (err, cell = square) with a number is painted black |
11 | * - no black cells have an adjacent (horz/vert) black cell |
12 | * - the white cells are all connected (through other white cells) |
13 | * - if a cell contains a number n, let h and v be the lengths of the |
14 | * maximal horizontal and vertical white sequences containing that |
15 | * cell. Then n must equal h + v - 1. |
16 | */ |
17 | |
18 | /* example instance with its encoding: |
19 | * |
20 | * +--+--+--+--+--+--+--+ |
21 | * | | | | | 7| | | |
22 | * +--+--+--+--+--+--+--+ |
23 | * | 3| | | | | | 8| |
24 | * +--+--+--+--+--+--+--+ |
25 | * | | | | | | 5| | |
26 | * +--+--+--+--+--+--+--+ |
27 | * | | | 7| | 7| | | |
28 | * +--+--+--+--+--+--+--+ |
29 | * | |13| | | | | | |
30 | * +--+--+--+--+--+--+--+ |
31 | * | 4| | | | | | 8| |
32 | * +--+--+--+--+--+--+--+ |
33 | * | | | 4| | | | | |
34 | * +--+--+--+--+--+--+--+ |
35 | * |
36 | * 7x7:d7b3e8e5c7a7c13e4d8b4d |
37 | */ |
38 | |
39 | #include <stdio.h> |
40 | #include <stdlib.h> |
41 | #include <string.h> |
42 | #include <assert.h> |
43 | #include <ctype.h> |
44 | #include <math.h> |
45 | |
46 | #include "puzzles.h" |
47 | |
48 | #include <stdarg.h> |
49 | |
50 | #define setmember(obj, field) ( (obj) . field = field ) |
51 | |
fd66a01d |
52 | static char *nfmtstr(int n, char *fmt, ...) { |
e7414d31 |
53 | va_list va; |
54 | char *ret = snewn(n+1, char); |
55 | va_start(va, fmt); |
56 | vsprintf(ret, fmt, va); |
57 | va_end(va); |
58 | return ret; |
59 | } |
60 | |
61 | #define SWAP(type, lvar1, lvar2) do { \ |
62 | type tmp = (lvar1); \ |
63 | (lvar1) = (lvar2); \ |
64 | (lvar2) = tmp; \ |
65 | } while (0) |
66 | |
67 | /* ---------------------------------------------------------------------- |
68 | * Game parameters, presets, states |
69 | */ |
70 | |
71 | typedef signed char puzzle_size; |
72 | |
73 | struct game_params { |
74 | puzzle_size w; |
75 | puzzle_size h; |
76 | }; |
77 | |
78 | struct game_state { |
79 | struct game_params params; |
80 | unsigned int has_cheated: 1; |
81 | unsigned int was_solved: 1; |
82 | puzzle_size *grid; |
83 | }; |
84 | |
85 | #define DEFAULT_PRESET 0 |
fd66a01d |
86 | static struct game_params range_presets[] = {{9, 6}, {12, 8}, {13, 9}, {16, 11}}; |
e7414d31 |
87 | /* rationale: I want all four combinations of {odd/even, odd/even}, as |
88 | * they play out differently with respect to two-way symmetry. I also |
89 | * want them to be generated relatively fast yet still be large enough |
90 | * to be entertaining for a decent amount of time, and I want them to |
91 | * make good use of monitor real estate (the typical screen resolution |
92 | * is why I do 13x9 and not 9x13). |
93 | */ |
94 | |
95 | static game_params *default_params(void) |
96 | { |
97 | game_params *ret = snew(game_params); |
fd66a01d |
98 | *ret = range_presets[DEFAULT_PRESET]; /* structure copy */ |
e7414d31 |
99 | return ret; |
100 | } |
101 | |
102 | static game_params *dup_params(game_params *params) |
103 | { |
104 | game_params *ret = snew(game_params); |
105 | *ret = *params; /* structure copy */ |
106 | return ret; |
107 | } |
108 | |
109 | static int game_fetch_preset(int i, char **name, game_params **params) |
110 | { |
fd66a01d |
111 | game_params *ret; |
e7414d31 |
112 | |
fd66a01d |
113 | if (i < 0 || i >= lenof(range_presets)) return FALSE; |
114 | |
115 | ret = default_params(); |
116 | *ret = range_presets[i]; /* struct copy */ |
117 | *params = ret; |
118 | |
119 | *name = nfmtstr(40, "%d x %d", range_presets[i].w, range_presets[i].h); |
e7414d31 |
120 | |
121 | return TRUE; |
122 | } |
123 | |
124 | static void free_params(game_params *params) |
125 | { |
126 | sfree(params); |
127 | } |
128 | |
129 | static void decode_params(game_params *params, char const *string) |
130 | { |
131 | /* FIXME check for puzzle_size overflow and decoding issues */ |
132 | params->w = params->h = atoi(string); |
133 | while (*string && isdigit((unsigned char) *string)) ++string; |
134 | if (*string == 'x') { |
135 | string++; |
136 | params->h = atoi(string); |
137 | while (*string && isdigit((unsigned char)*string)) string++; |
138 | } |
139 | } |
140 | |
141 | static char *encode_params(game_params *params, int full) |
142 | { |
143 | char str[80]; |
144 | sprintf(str, "%dx%d", params->w, params->h); |
145 | return dupstr(str); |
146 | } |
147 | |
148 | static config_item *game_configure(game_params *params) |
149 | { |
150 | config_item *ret; |
151 | |
152 | ret = snewn(3, config_item); |
153 | |
154 | ret[0].name = "Width"; |
155 | ret[0].type = C_STRING; |
156 | ret[0].sval = nfmtstr(10, "%d", params->w); |
157 | ret[0].ival = 0; |
158 | |
159 | ret[1].name = "Height"; |
160 | ret[1].type = C_STRING; |
161 | ret[1].sval = nfmtstr(10, "%d", params->h); |
162 | ret[1].ival = 0; |
163 | |
164 | ret[2].name = NULL; |
165 | ret[2].type = C_END; |
166 | ret[2].sval = NULL; |
167 | ret[2].ival = 0; |
168 | |
169 | return ret; |
170 | } |
171 | |
172 | static game_params *custom_params(config_item *configuration) |
173 | { |
174 | game_params *ret = snew(game_params); |
175 | ret->w = atoi(configuration[0].sval); |
176 | ret->h = atoi(configuration[1].sval); |
177 | return ret; |
178 | } |
179 | |
180 | #define memdup(dst, src, n, type) do { \ |
181 | dst = snewn(n, type); \ |
182 | memcpy(dst, src, n * sizeof (type)); \ |
183 | } while (0) |
184 | |
185 | static game_state *dup_game(game_state *state) |
186 | { |
187 | game_state *ret = snew(game_state); |
188 | int const n = state->params.w * state->params.h; |
189 | |
190 | *ret = *state; /* structure copy */ |
191 | |
192 | /* copy the poin_tee_, set a new value of the poin_ter_ */ |
193 | memdup(ret->grid, state->grid, n, puzzle_size); |
194 | |
195 | return ret; |
196 | } |
197 | |
198 | static void free_game(game_state *state) |
199 | { |
200 | sfree(state->grid); |
201 | sfree(state); |
202 | } |
203 | |
204 | |
205 | /* ---------------------------------------------------------------------- |
206 | * The solver subsystem. |
207 | * |
208 | * The solver is used for two purposes: |
209 | * - To solve puzzles when the user selects `Solve'. |
210 | * - To test solubility of a grid as clues are being removed from it |
211 | * during the puzzle generation. |
212 | * |
213 | * It supports the following ways of reasoning: |
214 | * |
215 | * - A cell adjacent to a black cell must be white. |
216 | * |
217 | * - If painting a square black would bisect the white regions, that |
218 | * square is white (by finding biconnected components' cut points) |
219 | * |
220 | * - A cell with number n, covering at most k white squares in three |
221 | * directions must white-cover n-k squares in the last direction. |
222 | * |
223 | * - A cell with number n known to cover k squares, if extending the |
224 | * cover by one square in a given direction causes the cell to |
225 | * cover _more_ than n squares, that extension cell must be black. |
226 | * |
227 | * (either if the square already covers n, or if it extends into a |
228 | * chunk of size > n - k) |
229 | * |
230 | * - Recursion. Pick any cell and see if this leads to either a |
231 | * contradiction or a solution (and then act appropriately). |
232 | * |
233 | * |
234 | * TODO: |
235 | * |
236 | * (propagation upper limit) |
237 | * - If one has two numbers on the same line, the smaller limits the |
238 | * larger. Example: in |b|_|_|8|4|_|_|b|, only two _'s can be both |
239 | * white and connected to the "8" cell; so that cell will propagate |
240 | * at least four cells orthogonally to the displayed line (which is |
241 | * better than the current "at least 2"). |
242 | * |
243 | * (propagation upper limit) |
244 | * - cells can't propagate into other cells if doing so exceeds that |
245 | * number. Example: in |b|4|.|.|2|b|, at most one _ can be white; |
246 | * otherwise, the |2| would have too many reaching white cells. |
247 | * |
248 | * (propagation lower and upper limit) |
249 | * - `Full Combo': in each four directions d_1 ... d_4, find a set of |
250 | * possible propagation distances S_1 ... S_4. For each i=1..4, |
251 | * for each x in S_i: if not exists (y, z, w) in the other sets |
252 | * such that (x+y+z+w+1 == clue value): then remove x from S_i. |
253 | * Repeat until this stabilizes. If any cell would contradict |
254 | */ |
255 | |
256 | #define idx(i, j, w) ((i)*(w) + (j)) |
257 | #define out_of_bounds(r, c, w, h) \ |
258 | ((r) < 0 || (r) >= h || (c) < 0 || (c) >= w) |
259 | |
260 | typedef struct square { |
261 | puzzle_size r, c; |
262 | } square; |
263 | |
264 | enum {BLACK = -2, WHITE, EMPTY}; |
265 | /* white is for pencil marks, empty is undecided */ |
266 | |
267 | static int const dr[4] = {+1, 0, -1, 0}; |
268 | static int const dc[4] = { 0, +1, 0, -1}; |
269 | static int const cursors[4] = /* must match dr and dc */ |
270 | {CURSOR_DOWN, CURSOR_RIGHT, CURSOR_UP, CURSOR_LEFT}; |
271 | |
272 | typedef struct move { |
273 | square square; |
274 | unsigned int colour: 1; |
275 | } move; |
276 | enum {M_BLACK = 0, M_WHITE = 1}; |
277 | |
278 | typedef move *(reasoning)(game_state *state, |
279 | int nclues, |
280 | const square *clues, |
281 | move *buf); |
282 | |
283 | static reasoning solver_reasoning_not_too_big; |
284 | static reasoning solver_reasoning_adjacency; |
285 | static reasoning solver_reasoning_connectedness; |
286 | static reasoning solver_reasoning_recursion; |
287 | |
288 | enum { |
289 | DIFF_NOT_TOO_BIG, |
290 | DIFF_ADJACENCY, |
291 | DIFF_CONNECTEDNESS, |
292 | DIFF_RECURSION |
293 | }; |
294 | |
295 | static move *solve_internal(game_state *state, move *base, int diff); |
296 | |
297 | static char *solve_game(game_state *orig, game_state *curpos, |
298 | char *aux, char **error) |
299 | { |
300 | int const n = orig->params.w * orig->params.h; |
301 | move *const base = snewn(n, move); |
302 | move *moves = solve_internal(orig, base, DIFF_RECURSION); |
303 | |
304 | char *ret = NULL; |
305 | |
306 | if (moves != NULL) { |
307 | int const k = moves - base; |
308 | char *str = ret = snewn(15*k + 2, char); |
309 | char colour[2] = "BW"; |
310 | move *it; |
311 | *str++ = 'S'; |
312 | *str = '\0'; |
313 | for (it = base; it < moves; ++it) |
314 | str += sprintf(str, "%c,%d,%d", colour[it->colour], |
315 | it->square.r, it->square.c); |
316 | } else *error = "This puzzle instance contains a contradiction"; |
317 | |
318 | sfree(base); |
319 | return ret; |
320 | } |
321 | |
322 | static square *find_clues(game_state *state, int *ret_nclues); |
323 | static move *do_solve(game_state *state, |
324 | int nclues, |
325 | const square *clues, |
326 | move *move_buffer, |
327 | int difficulty); |
328 | |
329 | /* new_game_desc entry point in the solver subsystem */ |
330 | static move *solve_internal(game_state *state, move *base, int diff) |
331 | { |
332 | int nclues; |
333 | square *const clues = find_clues(state, &nclues); |
334 | game_state *dup = dup_game(state); |
335 | move *const moves = do_solve(dup, nclues, clues, base, diff); |
336 | free_game(dup); |
337 | sfree(clues); |
338 | return moves; |
339 | } |
340 | |
fd66a01d |
341 | static reasoning *const reasonings[] = { |
342 | solver_reasoning_not_too_big, |
343 | solver_reasoning_adjacency, |
344 | solver_reasoning_connectedness, |
345 | solver_reasoning_recursion |
346 | }; |
347 | |
e7414d31 |
348 | static move *do_solve(game_state *state, |
349 | int nclues, |
350 | const square *clues, |
351 | move *move_buffer, |
352 | int difficulty) |
353 | { |
e7414d31 |
354 | struct move *buf = move_buffer, *oldbuf; |
355 | int i; |
356 | |
357 | do { |
358 | oldbuf = buf; |
359 | for (i = 0; i < lenof(reasonings) && i <= difficulty; ++i) { |
360 | /* only recurse if all else fails */ |
361 | if (i == DIFF_RECURSION && buf > oldbuf) continue; |
362 | buf = (*reasonings[i])(state, nclues, clues, buf); |
363 | if (buf == NULL) return NULL; |
364 | } |
365 | } while (buf > oldbuf); |
366 | |
367 | return buf; |
368 | } |
369 | |
370 | #define MASK(n) (1 << ((n) + 2)) |
371 | |
372 | static int runlength(puzzle_size r, puzzle_size c, |
373 | puzzle_size dr, puzzle_size dc, |
374 | game_state *state, int colourmask) |
375 | { |
376 | int const w = state->params.w, h = state->params.h; |
377 | int sz = 0; |
378 | while (TRUE) { |
379 | int cell = idx(r, c, w); |
380 | if (out_of_bounds(r, c, w, h)) break; |
381 | if (state->grid[cell] > 0) { |
382 | if (!(colourmask & ~(MASK(BLACK) | MASK(WHITE) | MASK(EMPTY)))) |
383 | break; |
384 | } else if (!(MASK(state->grid[cell]) & colourmask)) break; |
385 | ++sz; |
386 | r += dr; |
387 | c += dc; |
388 | } |
389 | return sz; |
390 | } |
391 | |
392 | static void solver_makemove(puzzle_size r, puzzle_size c, int colour, |
393 | game_state *state, move **buffer_ptr) |
394 | { |
395 | int const cell = idx(r, c, state->params.w); |
396 | if (out_of_bounds(r, c, state->params.w, state->params.h)) return; |
397 | if (state->grid[cell] != EMPTY) return; |
398 | setmember((*buffer_ptr)->square, r); |
399 | setmember((*buffer_ptr)->square, c); |
400 | setmember(**buffer_ptr, colour); |
401 | ++*buffer_ptr; |
402 | state->grid[cell] = (colour == M_BLACK ? BLACK : WHITE); |
403 | } |
404 | |
405 | static move *solver_reasoning_adjacency(game_state *state, |
406 | int nclues, |
407 | const square *clues, |
408 | move *buf) |
409 | { |
410 | int r, c, i; |
411 | for (r = 0; r < state->params.h; ++r) |
412 | for (c = 0; c < state->params.w; ++c) { |
413 | int const cell = idx(r, c, state->params.w); |
414 | if (state->grid[cell] != BLACK) continue; |
415 | for (i = 0; i < 4; ++i) |
416 | solver_makemove(r + dr[i], c + dc[i], M_WHITE, state, &buf); |
417 | } |
418 | return buf; |
419 | } |
420 | |
421 | enum {NOT_VISITED = -1}; |
422 | |
423 | static int dfs_biconnect_visit(puzzle_size r, puzzle_size c, |
424 | game_state *state, |
425 | square *dfs_parent, int *dfs_depth, |
426 | move **buf); |
427 | |
428 | static move *solver_reasoning_connectedness(game_state *state, |
429 | int nclues, |
430 | const square *clues, |
431 | move *buf) |
432 | { |
433 | int const w = state->params.w, h = state->params.h, n = w * h; |
434 | |
435 | square *const dfs_parent = snewn(n, square); |
436 | int *const dfs_depth = snewn(n, int); |
437 | |
438 | int i; |
439 | for (i = 0; i < n; ++i) { |
440 | dfs_parent[i].r = NOT_VISITED; |
441 | dfs_depth[i] = -n; |
442 | } |
443 | |
444 | for (i = 0; i < n && state->grid[i] == BLACK; ++i); |
445 | |
446 | dfs_parent[i].r = i / w; |
447 | dfs_parent[i].c = i % w; /* `dfs root`.parent == `dfs root` */ |
448 | dfs_depth[i] = 0; |
449 | |
450 | dfs_biconnect_visit(i / w, i % w, state, dfs_parent, dfs_depth, &buf); |
451 | |
452 | sfree(dfs_parent); |
453 | sfree(dfs_depth); |
454 | |
455 | return buf; |
456 | } |
457 | |
458 | /* returns the `lowpoint` of (r, c) */ |
459 | static int dfs_biconnect_visit(puzzle_size r, puzzle_size c, |
460 | game_state *state, |
461 | square *dfs_parent, int *dfs_depth, |
462 | move **buf) |
463 | { |
464 | const puzzle_size w = state->params.w, h = state->params.h; |
465 | int const i = idx(r, c, w), mydepth = dfs_depth[i]; |
466 | int lowpoint = mydepth, j, nchildren = 0; |
467 | |
468 | for (j = 0; j < 4; ++j) { |
469 | const puzzle_size rr = r + dr[j], cc = c + dc[j]; |
470 | int const cell = idx(rr, cc, w); |
471 | |
472 | if (out_of_bounds(rr, cc, w, h)) continue; |
473 | if (state->grid[cell] == BLACK) continue; |
474 | |
475 | if (dfs_parent[cell].r == NOT_VISITED) { |
476 | int child_lowpoint; |
477 | dfs_parent[cell].r = r; |
478 | dfs_parent[cell].c = c; |
479 | dfs_depth[cell] = mydepth + 1; |
480 | child_lowpoint = dfs_biconnect_visit(rr, cc, state, dfs_parent, |
481 | dfs_depth, buf); |
482 | |
483 | if (child_lowpoint >= mydepth && mydepth > 0) |
484 | solver_makemove(r, c, M_WHITE, state, buf); |
485 | |
486 | lowpoint = min(lowpoint, child_lowpoint); |
487 | ++nchildren; |
488 | } else if (rr != dfs_parent[i].r || cc != dfs_parent[i].c) { |
489 | lowpoint = min(lowpoint, dfs_depth[cell]); |
490 | } |
491 | } |
492 | |
493 | if (mydepth == 0 && nchildren >= 2) |
494 | solver_makemove(r, c, M_WHITE, state, buf); |
495 | |
496 | return lowpoint; |
497 | } |
498 | |
499 | static move *solver_reasoning_not_too_big(game_state *state, |
500 | int nclues, |
501 | const square *clues, |
502 | move *buf) |
503 | { |
504 | int const w = state->params.w, runmasks[4] = { |
505 | ~(MASK(BLACK) | MASK(EMPTY)), |
506 | MASK(EMPTY), |
507 | ~(MASK(BLACK) | MASK(EMPTY)), |
508 | ~(MASK(BLACK)) |
509 | }; |
510 | enum {RUN_WHITE, RUN_EMPTY, RUN_BEYOND, RUN_SPACE}; |
511 | |
512 | int i, runlengths[4][4]; |
513 | |
514 | for (i = 0; i < nclues; ++i) { |
515 | int j, k, whites, space; |
516 | |
517 | const puzzle_size row = clues[i].r, col = clues[i].c; |
518 | int const clue = state->grid[idx(row, col, w)]; |
519 | |
520 | for (j = 0; j < 4; ++j) { |
521 | puzzle_size r = row + dr[j], c = col + dc[j]; |
522 | runlengths[RUN_SPACE][j] = 0; |
523 | for (k = 0; k <= RUN_SPACE; ++k) { |
524 | int l = runlength(r, c, dr[j], dc[j], state, runmasks[k]); |
525 | if (k < RUN_SPACE) { |
526 | runlengths[k][j] = l; |
527 | r += dr[j] * l; |
528 | c += dc[j] * l; |
529 | } |
530 | runlengths[RUN_SPACE][j] += l; |
531 | } |
532 | } |
533 | |
534 | whites = 1; |
535 | for (j = 0; j < 4; ++j) whites += runlengths[RUN_WHITE][j]; |
536 | |
537 | for (j = 0; j < 4; ++j) { |
538 | int const delta = 1 + runlengths[RUN_WHITE][j]; |
539 | const puzzle_size r = row + delta * dr[j]; |
540 | const puzzle_size c = col + delta * dc[j]; |
541 | |
542 | if (whites == clue) { |
543 | solver_makemove(r, c, M_BLACK, state, &buf); |
544 | continue; |
545 | } |
546 | |
547 | if (runlengths[RUN_EMPTY][j] == 1 && |
548 | whites |
549 | + runlengths[RUN_EMPTY][j] |
550 | + runlengths[RUN_BEYOND][j] |
551 | > clue) { |
552 | solver_makemove(r, c, M_BLACK, state, &buf); |
553 | continue; |
554 | } |
555 | |
556 | if (whites |
557 | + runlengths[RUN_EMPTY][j] |
558 | + runlengths[RUN_BEYOND][j] |
559 | > clue) { |
560 | runlengths[RUN_SPACE][j] = |
561 | runlengths[RUN_WHITE][j] + |
562 | runlengths[RUN_EMPTY][j] - 1; |
563 | |
564 | if (runlengths[RUN_EMPTY][j] == 1) |
565 | solver_makemove(r, c, M_BLACK, state, &buf); |
566 | } |
567 | } |
568 | |
569 | space = 1; |
570 | for (j = 0; j < 4; ++j) space += runlengths[RUN_SPACE][j]; |
571 | for (j = 0; j < 4; ++j) { |
572 | puzzle_size r = row + dr[j], c = col + dc[j]; |
573 | |
574 | int k = space - runlengths[RUN_SPACE][j]; |
575 | if (k >= clue) continue; |
576 | |
577 | for (; k < clue; ++k, r += dr[j], c += dc[j]) |
578 | solver_makemove(r, c, M_WHITE, state, &buf); |
579 | } |
580 | } |
581 | return buf; |
582 | } |
583 | |
584 | static move *solver_reasoning_recursion(game_state *state, |
585 | int nclues, |
586 | const square *clues, |
587 | move *buf) |
588 | { |
589 | int const w = state->params.w, n = w * state->params.h; |
590 | int cell, colour; |
591 | |
592 | for (cell = 0; cell < n; ++cell) { |
593 | int const r = cell / w, c = cell % w; |
594 | int i; |
595 | game_state *newstate; |
596 | move *recursive_result; |
597 | |
598 | if (state->grid[cell] != EMPTY) continue; |
599 | |
600 | /* FIXME: add enum alias for smallest and largest (or N) */ |
601 | for (colour = M_BLACK; colour <= M_WHITE; ++colour) { |
602 | newstate = dup_game(state); |
603 | newstate->grid[cell] = colour; |
604 | recursive_result = do_solve(newstate, nclues, clues, buf, |
605 | DIFF_RECURSION); |
606 | free_game(newstate); |
607 | if (recursive_result == NULL) { |
608 | solver_makemove(r, c, M_BLACK + M_WHITE - colour, state, &buf); |
609 | return buf; |
610 | } |
611 | for (i = 0; i < n && newstate->grid[i] != EMPTY; ++i); |
612 | if (i == n) return buf; |
613 | } |
614 | } |
615 | return buf; |
616 | } |
617 | |
618 | static square *find_clues(game_state *state, int *ret_nclues) |
619 | { |
620 | int r, c, i, nclues = 0; |
621 | square *ret = snewn(state->params.w * state->params.h, struct square); |
622 | |
623 | for (i = r = 0; r < state->params.h; ++r) |
624 | for (c = 0; c < state->params.w; ++c, ++i) |
625 | if (state->grid[i] > 0) { |
626 | ret[nclues].r = r; |
627 | ret[nclues].c = c; |
628 | ++nclues; |
629 | } |
630 | |
631 | *ret_nclues = nclues; |
632 | return sresize(ret, nclues + (nclues == 0), square); |
633 | } |
634 | |
635 | /* ---------------------------------------------------------------------- |
636 | * Puzzle generation |
637 | * |
638 | * Generating kurodoko instances is rather straightforward: |
639 | * |
640 | * - Start with a white grid and add black squares at randomly chosen |
641 | * locations, unless colouring that square black would violate |
642 | * either the adjacency or connectedness constraints. |
643 | * |
644 | * - For each white square, compute the number it would contain if it |
645 | * were given as a clue. |
646 | * |
647 | * - From a starting point of "give _every_ white square as a clue", |
648 | * for each white square (in a random order), see if the board is |
649 | * solvable when that square is not given as a clue. If not, don't |
650 | * give it as a clue, otherwise do. |
651 | * |
652 | * This never fails, but it's only _almost_ what I do. The real final |
653 | * step is this: |
654 | * |
655 | * - From a starting point of "give _every_ white square as a clue", |
656 | * first remove all clues that are two-way rotationally symmetric |
657 | * to a black square. If this leaves the puzzle unsolvable, throw |
658 | * it out and try again. Otherwise, remove all _pairs_ of clues |
659 | * (that are rotationally symmetric) which can be removed without |
660 | * rendering the puzzle unsolvable. |
661 | * |
662 | * This can fail even if one only removes the black and symmetric |
663 | * clues; indeed it happens often (avg. once or twice per puzzle) when |
664 | * generating 1xN instances. (If you add black cells they must be in |
665 | * the end, and if you only add one, it's ambiguous where). |
666 | */ |
667 | |
668 | /* forward declarations of internal calls */ |
669 | static void newdesc_choose_black_squares(game_state *state, |
670 | const int *shuffle_1toN); |
671 | static void newdesc_compute_clues(game_state *state); |
672 | static int newdesc_strip_clues(game_state *state, int *shuffle_1toN); |
673 | static char *newdesc_encode_game_description(int n, puzzle_size *grid); |
674 | |
675 | static char *new_game_desc(game_params *params, random_state *rs, |
676 | char **aux, int interactive) |
677 | { |
678 | int const w = params->w, h = params->h, n = w * h; |
679 | |
680 | puzzle_size *const grid = snewn(n, puzzle_size); |
681 | int *const shuffle_1toN = snewn(n, int); |
682 | |
683 | int i, clues_removed; |
684 | |
685 | char *encoding; |
686 | |
687 | game_state state; |
688 | state.params = *params; |
689 | state.grid = grid; |
690 | |
691 | interactive = 0; /* I don't need it, I shouldn't use it*/ |
692 | |
693 | for (i = 0; i < n; ++i) shuffle_1toN[i] = i; |
694 | |
695 | while (TRUE) { |
696 | shuffle(shuffle_1toN, n, sizeof (int), rs); |
697 | newdesc_choose_black_squares(&state, shuffle_1toN); |
698 | |
699 | newdesc_compute_clues(&state); |
700 | |
701 | shuffle(shuffle_1toN, n, sizeof (int), rs); |
702 | clues_removed = newdesc_strip_clues(&state, shuffle_1toN); |
703 | |
704 | if (clues_removed < 0) continue; else break; |
705 | } |
706 | |
707 | encoding = newdesc_encode_game_description(n, grid); |
708 | |
709 | sfree(grid); |
710 | sfree(shuffle_1toN); |
711 | |
712 | return encoding; |
713 | } |
714 | |
715 | static int dfs_count_white(game_state *state, int cell); |
716 | |
717 | static void newdesc_choose_black_squares(game_state *state, |
718 | const int *shuffle_1toN) |
719 | { |
720 | int const w = state->params.w, h = state->params.h, n = w * h; |
721 | |
722 | int k, any_white_cell, n_black_cells; |
723 | |
724 | for (k = 0; k < n; ++k) state->grid[k] = WHITE; |
725 | |
726 | any_white_cell = shuffle_1toN[n - 1]; |
727 | n_black_cells = 0; |
728 | |
729 | /* I like the puzzles that result from n / 3, but maybe this |
730 | * could be made a (generation, i.e. non-full) parameter? */ |
731 | for (k = 0; k < n / 3; ++k) { |
732 | int const i = shuffle_1toN[k], c = i % w, r = i / w; |
733 | |
734 | int j; |
735 | for (j = 0; j < 4; ++j) { |
736 | int const rr = r + dr[j], cc = c + dc[j], cell = idx(rr, cc, w); |
737 | /* if you're out of bounds, we skip you */ |
738 | if (out_of_bounds(rr, cc, w, h)) continue; |
739 | if (state->grid[cell] == BLACK) break; /* I can't be black */ |
740 | } if (j < 4) continue; /* I have black neighbour: I'm white */ |
741 | |
742 | state->grid[i] = BLACK; |
743 | ++n_black_cells; |
744 | |
745 | j = dfs_count_white(state, any_white_cell); |
746 | if (j + n_black_cells < n) { |
747 | state->grid[i] = WHITE; |
748 | --n_black_cells; |
749 | } |
750 | } |
751 | } |
752 | |
753 | static void newdesc_compute_clues(game_state *state) |
754 | { |
755 | int const w = state->params.w, h = state->params.h; |
756 | int r, c; |
757 | |
758 | for (r = 0; r < h; ++r) { |
759 | int run_size = 0, c, cc; |
760 | for (c = 0; c <= w; ++c) { |
761 | if (c == w || state->grid[idx(r, c, w)] == BLACK) { |
762 | for (cc = c - run_size; cc < c; ++cc) |
763 | state->grid[idx(r, cc, w)] += run_size; |
764 | run_size = 0; |
765 | } else ++run_size; |
766 | } |
767 | } |
768 | |
769 | for (c = 0; c < w; ++c) { |
770 | int run_size = 0, r, rr; |
771 | for (r = 0; r <= h; ++r) { |
772 | if (r == h || state->grid[idx(r, c, w)] == BLACK) { |
773 | for (rr = r - run_size; rr < r; ++rr) |
774 | state->grid[idx(rr, c, w)] += run_size; |
775 | run_size = 0; |
776 | } else ++run_size; |
777 | } |
778 | } |
779 | } |
780 | |
781 | #define rotate(x) (n - 1 - (x)) |
782 | |
783 | static int newdesc_strip_clues(game_state *state, int *shuffle_1toN) |
784 | { |
785 | int const w = state->params.w, n = w * state->params.h; |
786 | |
787 | move *const move_buffer = snewn(n, move); |
788 | move *buf; |
789 | game_state *dupstate; |
790 | |
791 | /* |
792 | * do a partition/pivot of shuffle_1toN into three groups: |
793 | * (1) squares rotationally-symmetric to (3) |
794 | * (2) squares not in (1) or (3) |
795 | * (3) black squares |
796 | * |
797 | * They go from [0, left), [left, right) and [right, n) in |
798 | * shuffle_1toN (and from there into state->grid[ ]) |
799 | * |
800 | * Then, remove clues from the grid one by one in shuffle_1toN |
801 | * order, until the solver becomes unhappy. If we didn't remove |
802 | * all of (1), return (-1). Else, we're happy. |
803 | */ |
804 | |
805 | /* do the partition */ |
806 | int clues_removed, k = 0, left = 0, right = n; |
807 | |
808 | for (;; ++k) { |
809 | while (k < right && state->grid[shuffle_1toN[k]] == BLACK) { |
810 | --right; |
811 | SWAP(int, shuffle_1toN[right], shuffle_1toN[k]); |
812 | assert(state->grid[shuffle_1toN[right]] == BLACK); |
813 | } |
814 | if (k >= right) break; |
815 | assert (k >= left); |
816 | if (state->grid[rotate(shuffle_1toN[k])] == BLACK) { |
817 | SWAP(int, shuffle_1toN[k], shuffle_1toN[left]); |
818 | ++left; |
819 | } |
820 | assert (state->grid[rotate(shuffle_1toN[k])] != BLACK |
821 | || k == left - 1); |
822 | } |
823 | |
824 | for (k = 0; k < left; ++k) { |
825 | assert (state->grid[rotate(shuffle_1toN[k])] == BLACK); |
826 | state->grid[shuffle_1toN[k]] = EMPTY; |
827 | } |
828 | for (k = left; k < right; ++k) { |
829 | assert (state->grid[rotate(shuffle_1toN[k])] != BLACK); |
830 | assert (state->grid[shuffle_1toN[k]] != BLACK); |
831 | } |
832 | for (k = right; k < n; ++k) { |
833 | assert (state->grid[shuffle_1toN[k]] == BLACK); |
834 | state->grid[shuffle_1toN[k]] = EMPTY; |
835 | } |
836 | |
837 | clues_removed = (left - 0) + (n - right); |
838 | |
839 | dupstate = dup_game(state); |
840 | buf = solve_internal(dupstate, move_buffer, DIFF_RECURSION - 1); |
841 | free_game(dupstate); |
842 | if (buf - move_buffer < clues_removed) { |
843 | /* branch prediction: I don't think I'll go here */ |
844 | clues_removed = -1; |
845 | goto ret; |
846 | } |
847 | |
848 | for (k = left; k < right; ++k) { |
849 | const int i = shuffle_1toN[k], j = rotate(i); |
850 | int const clue = state->grid[i], clue_rot = state->grid[j]; |
851 | if (clue == BLACK) continue; |
852 | state->grid[i] = state->grid[j] = EMPTY; |
853 | dupstate = dup_game(state); |
854 | buf = solve_internal(dupstate, move_buffer, DIFF_RECURSION - 1); |
855 | free_game(dupstate); |
856 | clues_removed += 2 - (i == j); |
857 | /* if i is the center square, then i == (j = rotate(i)) |
858 | * when i and j are one, removing i and j removes only one */ |
859 | if (buf - move_buffer == clues_removed) continue; |
860 | /* if the solver is sound, refilling all removed clues means |
861 | * we have filled all squares, i.e. solved the puzzle. */ |
862 | state->grid[i] = clue; |
863 | state->grid[j] = clue_rot; |
864 | clues_removed -= 2 - (i == j); |
865 | } |
866 | |
867 | ret: |
868 | sfree(move_buffer); |
869 | return clues_removed; |
870 | } |
871 | |
872 | static int dfs_count_rec(puzzle_size *grid, int r, int c, int w, int h) |
873 | { |
874 | int const cell = idx(r, c, w); |
875 | if (out_of_bounds(r, c, w, h)) return 0; |
876 | if (grid[cell] != WHITE) return 0; |
877 | grid[cell] = EMPTY; |
878 | return 1 + |
879 | dfs_count_rec(grid, r + 0, c + 1, w, h) + |
880 | dfs_count_rec(grid, r + 0, c - 1, w, h) + |
881 | dfs_count_rec(grid, r + 1, c + 0, w, h) + |
882 | dfs_count_rec(grid, r - 1, c + 0, w, h); |
883 | } |
884 | |
885 | static int dfs_count_white(game_state *state, int cell) |
886 | { |
887 | int const w = state->params.w, h = state->params.h, n = w * h; |
888 | int const r = cell / w, c = cell % w; |
889 | int i, k = dfs_count_rec(state->grid, r, c, w, h); |
890 | for (i = 0; i < n; ++i) |
891 | if (state->grid[i] == EMPTY) |
892 | state->grid[i] = WHITE; |
893 | return k; |
894 | } |
895 | |
896 | static char *validate_params(game_params *params, int full) |
897 | { |
898 | int const w = params->w, h = params->h; |
899 | if (w < 1) return "Error: width is less than 1"; |
900 | if (h < 1) return "Error: height is less than 1"; |
901 | if (w * h < 1) return "Error: size is less than 1"; |
902 | if (w + h - 1 > SCHAR_MAX) return "Error: w + h is too big"; |
903 | /* I might be unable to store clues in my puzzle_size *grid; */ |
904 | if (full) { |
905 | if (w == 2 && h == 2) return "Error: can't create 2x2 puzzles"; |
906 | if (w == 1 && h == 2) return "Error: can't create 1x2 puzzles"; |
907 | if (w == 2 && h == 1) return "Error: can't create 2x1 puzzles"; |
908 | if (w == 1 && h == 1) return "Error: can't create 1x1 puzzles"; |
909 | } |
910 | return NULL; |
911 | } |
912 | |
913 | /* Definition: a puzzle instance is _good_ if: |
914 | * - it has a unique solution |
915 | * - the solver can find this solution without using recursion |
916 | * - the solution contains at least one black square |
917 | * - the clues are 2-way rotationally symmetric |
918 | * |
919 | * (the idea being: the generator can not output any _bad_ puzzles) |
920 | * |
921 | * Theorem: validate_params, when full != 0, discards exactly the set |
922 | * of parameters for which there are _no_ good puzzle instances. |
923 | * |
924 | * Proof: it's an immediate consequence of the five lemmas below. |
925 | * |
926 | * Observation: not only do puzzles on non-tiny grids exist, the |
927 | * generator is pretty fast about coming up with them. On my pre-2004 |
928 | * desktop box, it generates 100 puzzles on the highest preset (16x11) |
929 | * in 8.383 seconds, or <= 0.1 second per puzzle. |
930 | * |
931 | * ---------------------------------------------------------------------- |
932 | * |
933 | * Lemma: On a 1x1 grid, there are no good puzzles. |
934 | * |
935 | * Proof: the one square can't be a clue because at least one square |
936 | * is black. But both a white square and a black square satisfy the |
937 | * solution criteria, so the puzzle is ambiguous (and hence bad). |
938 | * |
939 | * Lemma: On a 1x2 grid, there are no good puzzles. |
940 | * |
941 | * Proof: let's name the squares l and r. Note that there can be at |
942 | * most one black square, or adjacency is violated. By assumption at |
943 | * least one square is black, so let's call that one l. By clue |
944 | * symmetry, neither l nor r can be given as a clue, so the puzzle |
945 | * instance is blank and thus ambiguous. |
946 | * |
947 | * Corollary: On a 2x1 grid, there are no good puzzles. |
948 | * Proof: rotate the above proof 90 degrees ;-) |
949 | * |
950 | * ---------------------------------------------------------------------- |
951 | * |
952 | * Lemma: On a 2x2 grid, there are no soluble puzzles with 2-way |
953 | * rotational symmetric clues and at least one black square. |
954 | * |
955 | * Proof: Let's name the squares a, b, c, and d, with a and b on the |
956 | * top row, a and c in the left column. Let's consider the case where |
957 | * a is black. Then no other square can be black: b and c would both |
958 | * violate the adjacency constraint; d would disconnect b from c. |
959 | * |
960 | * So exactly one square is black (and by 4-way rotation symmetry of |
961 | * the 2x2 square, it doesn't matter which one, so let's stick to a). |
962 | * By 2-way rotational symmetry of the clues and the rule about not |
963 | * painting numbers black, neither a nor d can be clues. A blank |
964 | * puzzle would be ambiguous, so one of {b, c} is a clue; by symmetry, |
965 | * so is the other one. |
966 | * |
967 | * It is readily seen that their clue value is 2. But "a is black" |
968 | * and "d is black" are both valid solutions in this case, so the |
969 | * puzzle is ambiguous (and hence bad). |
970 | * |
971 | * ---------------------------------------------------------------------- |
972 | * |
973 | * Lemma: On a wxh grid with w, h >= 1 and (w > 2 or h > 2), there is |
974 | * at least one good puzzle. |
975 | * |
976 | * Proof: assume that w > h (otherwise rotate the proof again). Paint |
977 | * the top left and bottom right corners black, and fill a clue into |
978 | * all the other squares. Present this board to the solver code (or |
979 | * player, hypothetically), except with the two black squares as blank |
980 | * squares. |
981 | * |
982 | * For an Nx1 puzzle, observe that every clue is N - 2, and there are |
983 | * N - 2 of them in one connected sequence, so the remaining two |
984 | * squares can be deduced to be black, which solves the puzzle. |
985 | * |
986 | * For any other puzzle, let j be a cell in the same row as a black |
987 | * cell, but not in the same column (such a cell doesn't exist in 2x3 |
988 | * puzzles, but we assume w > h and such cells exist in 3x2 puzzles). |
989 | * |
990 | * Note that the number of cells in axis parallel `rays' going out |
991 | * from j exceeds j's clue value by one. Only one such cell is a |
992 | * non-clue, so it must be black. Similarly for the other corner (let |
993 | * j' be a cell in the same row as the _other_ black cell, but not in |
994 | * the same column as _any_ black cell; repeat this argument at j'). |
995 | * |
996 | * This fills the grid and satisfies all clues and the adjacency |
997 | * constraint and doesn't paint on top of any clues. All that is left |
998 | * to see is connectedness. |
999 | * |
1000 | * Observe that the white cells in each column form a single connected |
1001 | * `run', and each column contains a white cell adjacent to a white |
1002 | * cell in the column to the right, if that column exists. |
1003 | * |
1004 | * Thus, any cell in the left-most column can reach any other cell: |
1005 | * first go to the target column (by repeatedly going to the cell in |
1006 | * your current column that lets you go right, then going right), then |
1007 | * go up or down to the desired cell. |
1008 | * |
1009 | * As reachability is symmetric (in undirected graphs) and transitive, |
1010 | * any cell can reach any left-column cell, and from there any other |
1011 | * cell. |
1012 | */ |
1013 | |
1014 | /* ---------------------------------------------------------------------- |
1015 | * Game encoding and decoding |
1016 | */ |
1017 | |
1018 | #define NDIGITS_BASE '!' |
1019 | |
1020 | static char *newdesc_encode_game_description(int area, puzzle_size *grid) |
1021 | { |
1022 | char *desc = NULL; |
1023 | int desclen = 0, descsize = 0; |
1024 | int run, i; |
1025 | |
1026 | run = 0; |
1027 | for (i = 0; i <= area; i++) { |
1028 | int n = (i < area ? grid[i] : -1); |
1029 | |
1030 | if (!n) |
1031 | run++; |
1032 | else { |
1033 | if (descsize < desclen + 40) { |
1034 | descsize = desclen * 3 / 2 + 40; |
1035 | desc = sresize(desc, descsize, char); |
1036 | } |
1037 | if (run) { |
1038 | while (run > 0) { |
1039 | int c = 'a' - 1 + run; |
1040 | if (run > 26) |
1041 | c = 'z'; |
1042 | desc[desclen++] = c; |
1043 | run -= c - ('a' - 1); |
1044 | } |
1045 | } else { |
1046 | /* |
1047 | * If there's a number in the very top left or |
1048 | * bottom right, there's no point putting an |
1049 | * unnecessary _ before or after it. |
1050 | */ |
1051 | if (desclen > 0 && n > 0) |
1052 | desc[desclen++] = '_'; |
1053 | } |
1054 | if (n > 0) |
1055 | desclen += sprintf(desc+desclen, "%d", n); |
1056 | run = 0; |
1057 | } |
1058 | } |
1059 | desc[desclen] = '\0'; |
1060 | return desc; |
1061 | } |
1062 | |
1063 | static char *validate_desc(game_params *params, char *desc) |
1064 | { |
1065 | int const n = params->w * params->h; |
1066 | int squares = 0; |
1067 | int range = params->w + params->h - 1; /* maximum cell value */ |
1068 | |
1069 | while (*desc && *desc != ',') { |
1070 | int c = *desc++; |
1071 | if (c >= 'a' && c <= 'z') { |
1072 | squares += c - 'a' + 1; |
1073 | } else if (c == '_') { |
1074 | /* do nothing */; |
1075 | } else if (c > '0' && c <= '9') { |
1076 | int val = atoi(desc-1); |
1077 | if (val < 1 || val > range) |
1078 | return "Out-of-range number in game description"; |
1079 | squares++; |
1080 | while (*desc >= '0' && *desc <= '9') |
1081 | desc++; |
1082 | } else |
1083 | return "Invalid character in game description"; |
1084 | } |
1085 | |
1086 | if (squares < n) |
1087 | return "Not enough data to fill grid"; |
1088 | |
1089 | if (squares > n) |
1090 | return "Too much data to fit in grid"; |
1091 | |
1092 | return NULL; |
1093 | } |
1094 | |
1095 | static game_state *new_game(midend *me, game_params *params, char *desc) |
1096 | { |
1097 | int i; |
1098 | char *p; |
1099 | |
1100 | int const n = params->w * params->h; |
1101 | game_state *state = snew(game_state); |
1102 | |
1103 | me = NULL; /* I don't need it, I shouldn't use it */ |
1104 | |
1105 | state->params = *params; /* structure copy */ |
1106 | state->grid = snewn(n, puzzle_size); |
1107 | |
1108 | p = desc; |
1109 | i = 0; |
1110 | while (i < n && *p) { |
1111 | int c = *p++; |
1112 | if (c >= 'a' && c <= 'z') { |
1113 | int squares = c - 'a' + 1; |
1114 | while (squares--) |
1115 | state->grid[i++] = 0; |
1116 | } else if (c == '_') { |
1117 | /* do nothing */; |
1118 | } else if (c > '0' && c <= '9') { |
1119 | int val = atoi(p-1); |
1120 | assert(val >= 1 && val <= params->w+params->h-1); |
1121 | state->grid[i++] = val; |
1122 | while (*p >= '0' && *p <= '9') |
1123 | p++; |
1124 | } |
1125 | } |
1126 | assert(i == n); |
1127 | state->has_cheated = FALSE; |
1128 | state->was_solved = FALSE; |
1129 | |
1130 | return state; |
1131 | } |
1132 | |
1133 | /* ---------------------------------------------------------------------- |
1134 | * User interface: ascii |
1135 | */ |
1136 | |
1137 | static int game_can_format_as_text_now(game_params *params) |
1138 | { |
1139 | return TRUE; |
1140 | } |
1141 | |
1142 | static char *game_text_format(game_state *state) |
1143 | { |
1144 | int cellsize, r, c, i, w_string, h_string, n_string; |
1145 | char *ret, *buf, *gridline; |
1146 | |
1147 | int const w = state->params.w, h = state->params.h; |
1148 | |
1149 | cellsize = 0; /* or may be used uninitialized */ |
1150 | |
1151 | for (c = 0; c < w; ++c) { |
1152 | for (r = 1; r < h; ++r) { |
1153 | puzzle_size k = state->grid[idx(r, c, w)]; |
1154 | int d; |
1155 | for (d = 0; k; k /= 10, ++d); |
1156 | cellsize = max(cellsize, d); |
1157 | } |
1158 | } |
1159 | |
1160 | ++cellsize; |
1161 | |
1162 | w_string = w * cellsize + 2; /* "|%d|%d|...|\n" */ |
1163 | h_string = 2 * h + 1; /* "+--+--+...+\n%s\n+--+--+...+\n" */ |
1164 | n_string = w_string * h_string; |
1165 | |
1166 | gridline = snewn(w_string + 1, char); /* +1: NUL terminator */ |
1167 | memset(gridline, '-', w_string); |
1168 | for (c = 0; c <= w; ++c) gridline[c * cellsize] = '+'; |
1169 | gridline[w_string - 1] = '\n'; |
1170 | gridline[w_string - 0] = '\0'; |
1171 | |
1172 | buf = ret = snewn(n_string + 1, char); /* +1: NUL terminator */ |
1173 | for (i = r = 0; r < h; ++r) { |
1174 | memcpy(buf, gridline, w_string); |
1175 | buf += w_string; |
1176 | for (c = 0; c < w; ++c, ++i) { |
1177 | char ch; |
1178 | switch (state->grid[i]) { |
1179 | case BLACK: ch = '#'; break; |
1180 | case WHITE: ch = '.'; break; |
1181 | case EMPTY: ch = ' '; break; |
1182 | default: |
1183 | buf += sprintf(buf, "|%*d", cellsize - 1, state->grid[i]); |
1184 | continue; |
1185 | } |
1186 | *buf++ = '|'; |
1187 | memset(buf, ch, cellsize - 1); |
1188 | buf += cellsize - 1; |
1189 | } |
1190 | buf += sprintf(buf, "|\n"); |
1191 | } |
1192 | memcpy(buf, gridline, w_string); |
1193 | buf += w_string; |
1194 | assert (buf - ret == n_string); |
1195 | *buf = '\0'; |
1196 | |
1197 | sfree(gridline); |
1198 | |
1199 | return ret; |
1200 | } |
1201 | |
1202 | /* ---------------------------------------------------------------------- |
1203 | * User interfaces: interactive |
1204 | */ |
1205 | |
1206 | struct game_ui { |
1207 | puzzle_size r, c; /* cursor position */ |
1208 | unsigned int cursor_show: 1; |
e7414d31 |
1209 | }; |
1210 | |
1211 | static game_ui *new_ui(game_state *state) |
1212 | { |
1213 | struct game_ui *ui = snew(game_ui); |
1214 | ui->r = ui->c = 0; |
ed375bd3 |
1215 | ui->cursor_show = FALSE; |
e7414d31 |
1216 | return ui; |
1217 | } |
1218 | |
1219 | static void free_ui(game_ui *ui) |
1220 | { |
1221 | sfree(ui); |
1222 | } |
1223 | |
1224 | static char *encode_ui(game_ui *ui) |
1225 | { |
ed375bd3 |
1226 | return NULL; |
e7414d31 |
1227 | } |
1228 | |
1229 | static void decode_ui(game_ui *ui, char *encoding) |
1230 | { |
e7414d31 |
1231 | } |
1232 | |
1233 | typedef struct drawcell { |
1234 | puzzle_size value; |
1235 | unsigned int error: 1; |
1236 | unsigned int cursor: 1; |
1237 | unsigned int flash: 1; |
1238 | } drawcell; |
1239 | |
1240 | struct game_drawstate { |
1241 | int tilesize; |
1242 | drawcell *grid; |
1243 | unsigned int started: 1; |
1244 | }; |
1245 | |
1246 | #define TILESIZE (ds->tilesize) |
1247 | #define BORDER (TILESIZE / 2) |
1248 | #define COORD(x) ((x) * TILESIZE + BORDER) |
1249 | #define FROMCOORD(x) (((x) - BORDER) / TILESIZE) |
1250 | |
1251 | static char *interpret_move(game_state *state, game_ui *ui, game_drawstate *ds, |
1252 | int x, int y, int button) |
1253 | { |
1254 | enum {none, forwards, backwards, hint}; |
1255 | int const w = state->params.w, h = state->params.h; |
1256 | int r = ui->r, c = ui->c, action = none, cell; |
1257 | |
1258 | if (IS_CURSOR_SELECT(button) && !ui->cursor_show) return NULL; |
1259 | |
1260 | if (IS_MOUSE_DOWN(button)) { |
1261 | r = FROMCOORD(y + TILESIZE) - 1; /* or (x, y) < TILESIZE) */ |
1262 | c = FROMCOORD(x + TILESIZE) - 1; /* are considered inside */ |
1263 | if (out_of_bounds(r, c, w, h)) return NULL; |
1264 | ui->r = r; |
1265 | ui->c = c; |
1266 | ui->cursor_show = FALSE; |
1267 | } |
1268 | |
1269 | if (button == LEFT_BUTTON || button == RIGHT_BUTTON) { |
1270 | /* |
1271 | * Utterly awful hack, exactly analogous to the one in Slant, |
1272 | * to configure the left and right mouse buttons the opposite |
1273 | * way round. |
1274 | * |
1275 | * The original puzzle submitter thought it would be more |
1276 | * useful to have the left button turn an empty square into a |
1277 | * dotted one, on the grounds that that was what you did most |
1278 | * often; I (SGT) felt instinctively that the left button |
1279 | * ought to place black squares and the right button place |
1280 | * dots, on the grounds that that was consistent with many |
1281 | * other puzzles in which the left button fills in the data |
1282 | * used by the solution checker while the right button places |
1283 | * pencil marks for the user's convenience. |
1284 | * |
1285 | * My first beta-player wasn't sure either, so I thought I'd |
1286 | * pre-emptively put in a 'configuration' mechanism just in |
1287 | * case. |
1288 | */ |
1289 | { |
1290 | static int swap_buttons = -1; |
1291 | if (swap_buttons < 0) { |
1292 | char *env = getenv("RANGE_SWAP_BUTTONS"); |
1293 | swap_buttons = (env && (env[0] == 'y' || env[0] == 'Y')); |
1294 | } |
1295 | if (swap_buttons) { |
1296 | if (button == LEFT_BUTTON) |
1297 | button = RIGHT_BUTTON; |
1298 | else |
1299 | button = LEFT_BUTTON; |
1300 | } |
1301 | } |
1302 | } |
1303 | |
1304 | switch (button) { |
1305 | case CURSOR_SELECT : case LEFT_BUTTON: action = backwards; break; |
1306 | case CURSOR_SELECT2: case RIGHT_BUTTON: action = forwards; break; |
1307 | case 'h': case 'H' : action = hint; break; |
1308 | case CURSOR_UP: case CURSOR_DOWN: |
1309 | case CURSOR_LEFT: case CURSOR_RIGHT: |
1310 | if (ui->cursor_show) { |
1311 | int i; |
1312 | for (i = 0; i < 4 && cursors[i] != button; ++i); |
1313 | assert (i < 4); |
1314 | if (!out_of_bounds(ui->r + dr[i], ui->c + dc[i], w, h)) { |
1315 | ui->r += dr[i]; |
1316 | ui->c += dc[i]; |
1317 | } |
1318 | } else ui->cursor_show = TRUE; |
1319 | return ""; |
1320 | } |
1321 | |
1322 | if (action == hint) { |
1323 | move *end, *buf = snewn(state->params.w * state->params.h, |
1324 | struct move); |
1325 | char *ret = NULL; |
1326 | end = solve_internal(state, buf, DIFF_RECURSION); |
1327 | if (end != NULL && end > buf) { |
1328 | ret = nfmtstr(40, "%c,%d,%d", |
1329 | buf->colour == M_BLACK ? 'B' : 'W', |
1330 | buf->square.r, buf->square.c); |
ed375bd3 |
1331 | /* We used to set a flag here in the game_ui indicating |
1332 | * that the player had used the hint function. I (SGT) |
1333 | * retired it, on grounds of consistency with other games |
1334 | * (most of these games will still flash to indicate |
1335 | * completion if you solved and undid it, so why not if |
1336 | * you got a hint?) and because the flash is as much about |
1337 | * checking you got it all right than about congratulating |
1338 | * you on a job well done. */ |
e7414d31 |
1339 | } |
1340 | sfree(buf); |
1341 | return ret; |
1342 | } |
1343 | |
1344 | cell = state->grid[idx(r, c, state->params.w)]; |
1345 | if (cell > 0) return NULL; |
1346 | |
1347 | if (action == forwards) switch (cell) { |
1348 | case EMPTY: return nfmtstr(40, "W,%d,%d", r, c); |
1349 | case WHITE: return nfmtstr(40, "B,%d,%d", r, c); |
1350 | case BLACK: return nfmtstr(40, "E,%d,%d", r, c); |
1351 | } |
1352 | |
1353 | else if (action == backwards) switch (cell) { |
1354 | case BLACK: return nfmtstr(40, "W,%d,%d", r, c); |
1355 | case WHITE: return nfmtstr(40, "E,%d,%d", r, c); |
1356 | case EMPTY: return nfmtstr(40, "B,%d,%d", r, c); |
1357 | } |
1358 | |
1359 | return NULL; |
1360 | } |
1361 | |
1362 | static int find_errors(game_state *state, int *report) |
1363 | { |
1364 | int const w = state->params.w, h = state->params.h, n = w * h; |
1365 | |
1366 | int r, c, i; |
1367 | |
1368 | int nblack = 0, any_white_cell = -1; |
1369 | game_state *dup = dup_game(state); |
1370 | |
1371 | for (i = r = 0; r < h; ++r) |
1372 | for (c = 0; c < w; ++c, ++i) { |
1373 | switch (state->grid[i]) { |
1374 | |
1375 | case BLACK: |
1376 | { |
1377 | int j; |
1378 | ++nblack; |
1379 | for (j = 0; j < 4; ++j) { |
1380 | int const rr = r + dr[j], cc = c + dc[j]; |
1381 | if (out_of_bounds(rr, cc, w, h)) continue; |
1382 | if (state->grid[idx(rr, cc, w)] != BLACK) continue; |
1383 | if (!report) goto found_error; |
1384 | report[i] = TRUE; |
1385 | break; |
1386 | } |
1387 | } |
1388 | break; |
1389 | default: |
1390 | { |
1391 | int j, runs; |
1392 | for (runs = 1, j = 0; j < 4; ++j) { |
1393 | int const rr = r + dr[j], cc = c + dc[j]; |
1394 | runs += runlength(rr, cc, dr[j], dc[j], state, |
1395 | ~MASK(BLACK)); |
1396 | } |
1397 | if (!report) { |
1398 | if (runs != state->grid[i]) goto found_error; |
1399 | } else if (runs < state->grid[i]) report[i] = TRUE; |
1400 | else { |
1401 | for (runs = 1, j = 0; j < 4; ++j) { |
1402 | int const rr = r + dr[j], cc = c + dc[j]; |
1403 | runs += runlength(rr, cc, dr[j], dc[j], state, |
1404 | ~(MASK(BLACK) | MASK(EMPTY))); |
1405 | } |
1406 | if (runs > state->grid[i]) report[i] = TRUE; |
1407 | } |
1408 | } |
1409 | |
1410 | /* note: fallthrough _into_ these cases */ |
1411 | case EMPTY: |
1412 | case WHITE: any_white_cell = i; |
1413 | } |
1414 | } |
1415 | |
1416 | for (i = 0; i < n; ++i) if (dup->grid[i] != BLACK) dup->grid[i] = WHITE; |
1417 | if (nblack + dfs_count_white(dup, any_white_cell) < n) { |
1418 | if (!report) { |
1419 | printf("dfs fail at %d\n", any_white_cell); |
1420 | goto found_error; |
1421 | } |
1422 | for (i = 0; i < n; ++i) if (state->grid[i] != BLACK) report[i] = TRUE; |
1423 | } |
1424 | |
1425 | free_game(dup); |
1426 | return FALSE; /* if report != NULL, this is ignored */ |
1427 | |
1428 | found_error: |
1429 | free_game(dup); |
1430 | return TRUE; |
1431 | } |
1432 | |
1433 | static game_state *execute_move(game_state *state, char *move) |
1434 | { |
1435 | signed int r, c, value, nchars, ntok; |
1436 | signed char what_to_do; |
1437 | game_state *ret; |
1438 | |
1439 | assert (move); |
1440 | |
1441 | ret = dup_game(state); |
1442 | |
1443 | if (*move == 'S') { |
1444 | ++move; |
1445 | ret->has_cheated = ret->was_solved = TRUE; |
1446 | } |
1447 | |
1448 | for (; *move; move += nchars) { |
1449 | ntok = sscanf(move, "%c,%d,%d%n", &what_to_do, &r, &c, &nchars); |
1450 | if (ntok < 3) goto failure; |
1451 | switch (what_to_do) { |
1452 | case 'W': value = WHITE; break; |
1453 | case 'E': value = EMPTY; break; |
1454 | case 'B': value = BLACK; break; |
1455 | default: goto failure; |
1456 | } |
1457 | if (out_of_bounds(r, c, ret->params.w, ret->params.h)) goto failure; |
1458 | ret->grid[idx(r, c, ret->params.w)] = value; |
1459 | } |
1460 | |
1461 | if (ret->was_solved == FALSE) |
1462 | ret->was_solved = !find_errors(ret, NULL); |
1463 | |
1464 | return ret; |
1465 | |
1466 | failure: |
1467 | free_game(ret); |
1468 | return NULL; |
1469 | } |
1470 | |
1471 | static void game_changed_state(game_ui *ui, game_state *oldstate, |
1472 | game_state *newstate) |
1473 | { |
e7414d31 |
1474 | } |
1475 | |
1476 | static float game_anim_length(game_state *oldstate, game_state *newstate, |
1477 | int dir, game_ui *ui) |
1478 | { |
1479 | return 0.0F; |
1480 | } |
1481 | |
1482 | #define FLASH_TIME 0.7F |
1483 | |
1484 | static float game_flash_length(game_state *from, game_state *to, |
1485 | int dir, game_ui *ui) |
1486 | { |
ed375bd3 |
1487 | if (!from->was_solved && to->was_solved && !to->has_cheated) |
e7414d31 |
1488 | return FLASH_TIME; |
1489 | return 0.0F; |
1490 | } |
1491 | |
1cea529f |
1492 | static int game_status(game_state *state) |
4496362f |
1493 | { |
1cea529f |
1494 | return state->was_solved ? +1 : 0; |
4496362f |
1495 | } |
1496 | |
e7414d31 |
1497 | /* ---------------------------------------------------------------------- |
1498 | * Drawing routines. |
1499 | */ |
1500 | |
1501 | #define PREFERRED_TILE_SIZE 32 |
1502 | |
1503 | enum { |
1504 | COL_BACKGROUND = 0, |
1505 | COL_GRID, |
1506 | COL_BLACK = COL_GRID, |
1507 | COL_TEXT = COL_GRID, |
1508 | COL_USER = COL_GRID, |
1509 | COL_ERROR, |
1510 | COL_LOWLIGHT, |
1511 | COL_HIGHLIGHT = COL_ERROR, /* mkhighlight needs it, I don't */ |
1512 | COL_CURSOR = COL_LOWLIGHT, |
1513 | NCOLOURS |
1514 | }; |
1515 | |
1516 | static void game_compute_size(game_params *params, int tilesize, |
1517 | int *x, int *y) |
1518 | { |
1519 | *x = (1 + params->w) * tilesize; |
1520 | *y = (1 + params->h) * tilesize; |
1521 | } |
1522 | |
1523 | static void game_set_size(drawing *dr, game_drawstate *ds, |
1524 | game_params *params, int tilesize) |
1525 | { |
1526 | ds->tilesize = tilesize; |
1527 | } |
1528 | |
1529 | #define COLOUR(ret, i, r, g, b) \ |
1530 | ((ret[3*(i)+0] = (r)), (ret[3*(i)+1] = (g)), (ret[3*(i)+2] = (b))) |
1531 | |
1532 | static float *game_colours(frontend *fe, int *ncolours) |
1533 | { |
1534 | float *ret = snewn(3 * NCOLOURS, float); |
1535 | |
1536 | game_mkhighlight(fe, ret, COL_BACKGROUND, COL_HIGHLIGHT, COL_LOWLIGHT); |
1537 | COLOUR(ret, COL_GRID, 0.0F, 0.0F, 0.0F); |
1538 | COLOUR(ret, COL_ERROR, 1.0F, 0.0F, 0.0F); |
1539 | |
1540 | *ncolours = NCOLOURS; |
1541 | return ret; |
1542 | } |
1543 | |
1544 | static drawcell makecell(puzzle_size value, int error, int cursor, int flash) |
1545 | { |
1546 | drawcell ret; |
1547 | setmember(ret, value); |
1548 | setmember(ret, error); |
1549 | setmember(ret, cursor); |
1550 | setmember(ret, flash); |
1551 | return ret; |
1552 | } |
1553 | |
1554 | static game_drawstate *game_new_drawstate(drawing *dr, game_state *state) |
1555 | { |
1556 | int const w = state->params.w, h = state->params.h, n = w * h; |
1557 | struct game_drawstate *ds = snew(struct game_drawstate); |
1558 | int i; |
1559 | |
1560 | ds->tilesize = 0; |
1561 | ds->started = FALSE; |
1562 | |
1563 | ds->grid = snewn(n, drawcell); |
1564 | for (i = 0; i < n; ++i) |
1565 | ds->grid[i] = makecell(w + h, FALSE, FALSE, FALSE); |
1566 | |
1567 | return ds; |
1568 | } |
1569 | |
1570 | static void game_free_drawstate(drawing *dr, game_drawstate *ds) |
1571 | { |
1572 | sfree(ds->grid); |
1573 | sfree(ds); |
1574 | } |
1575 | |
1576 | #define cmpmember(a, b, field) ((a) . field == (b) . field) |
1577 | |
1578 | static int cell_eq(drawcell a, drawcell b) |
1579 | { |
1580 | return |
1581 | cmpmember(a, b, value) && |
1582 | cmpmember(a, b, error) && |
1583 | cmpmember(a, b, cursor) && |
1584 | cmpmember(a, b, flash); |
1585 | } |
1586 | |
1587 | static void draw_cell(drawing *dr, game_drawstate *ds, int r, int c, |
1588 | drawcell cell); |
1589 | |
1590 | static void game_redraw(drawing *dr, game_drawstate *ds, game_state *oldstate, |
1591 | game_state *state, int dir, game_ui *ui, |
1592 | float animtime, float flashtime) |
1593 | { |
1594 | int const w = state->params.w, h = state->params.h, n = w * h; |
1595 | int const wpx = (w+1) * ds->tilesize, hpx = (h+1) * ds->tilesize; |
1596 | int const flash = ((int) (flashtime * 5 / FLASH_TIME)) % 2; |
1597 | |
1598 | int r, c, i; |
1599 | |
1600 | int *errors = snewn(n, int); |
1601 | memset(errors, FALSE, n * sizeof (int)); |
1602 | find_errors(state, errors); |
1603 | |
1604 | assert (oldstate == NULL); /* only happens if animating moves */ |
1605 | |
1606 | if (!ds->started) { |
1607 | ds->started = TRUE; |
1608 | draw_rect(dr, 0, 0, wpx, hpx, COL_BACKGROUND); |
1609 | draw_rect(dr, BORDER-1, BORDER-1, |
1610 | ds->tilesize*w+2, ds->tilesize*h+2, COL_GRID); |
1611 | draw_update(dr, 0, 0, wpx, hpx); |
1612 | } |
1613 | |
1614 | for (i = r = 0; r < h; ++r) { |
1615 | for (c = 0; c < w; ++c, ++i) { |
1616 | drawcell cell = makecell(state->grid[i], errors[i], FALSE, flash); |
1617 | if (r == ui->r && c == ui->c && ui->cursor_show) |
1618 | cell.cursor = TRUE; |
1619 | if (!cell_eq(cell, ds->grid[i])) { |
1620 | draw_cell(dr, ds, r, c, cell); |
1621 | ds->grid[i] = cell; |
1622 | } |
1623 | } |
1624 | } |
1625 | |
1626 | sfree(errors); |
1627 | } |
1628 | |
1629 | static void draw_cell(drawing *draw, game_drawstate *ds, int r, int c, |
1630 | drawcell cell) |
1631 | { |
1632 | int const ts = ds->tilesize; |
1633 | int const y = BORDER + ts * r, x = BORDER + ts * c; |
1634 | int const tx = x + (ts / 2), ty = y + (ts / 2); |
1635 | int const dotsz = (ds->tilesize + 9) / 10; |
1636 | |
1637 | int const colour = (cell.value == BLACK ? |
1638 | cell.error ? COL_ERROR : COL_BLACK : |
1639 | cell.flash || cell.cursor ? |
1640 | COL_LOWLIGHT : COL_BACKGROUND); |
1641 | |
1642 | draw_rect (draw, x, y, ts, ts, colour); |
1643 | draw_rect_outline(draw, x, y, ts, ts, COL_GRID); |
1644 | |
1645 | switch (cell.value) { |
1646 | case WHITE: draw_rect(draw, tx - dotsz / 2, ty - dotsz / 2, dotsz, dotsz, |
1647 | cell.error ? COL_ERROR : COL_USER); |
1648 | case BLACK: break; |
1649 | case EMPTY: |
1650 | if (cell.error) |
1651 | draw_circle(draw, tx, ty, dotsz / 2, COL_ERROR, COL_GRID); |
1652 | break; |
1653 | default: |
1654 | { |
1655 | int const colour = (cell.error ? COL_ERROR : COL_GRID); |
1656 | char *msg = nfmtstr(10, "%d", cell.value); |
1657 | draw_text(draw, tx, ty, FONT_VARIABLE, ts * 3 / 5, |
1658 | ALIGN_VCENTRE | ALIGN_HCENTRE, colour, msg); |
1659 | sfree(msg); |
1660 | } |
1661 | } |
1662 | |
1663 | draw_update(draw, x, y, ts, ts); |
1664 | } |
1665 | |
1666 | static int game_timing_state(game_state *state, game_ui *ui) |
1667 | { |
1668 | puts("warning: game_timing_state was called (this shouldn't happen)"); |
1669 | return FALSE; /* the (non-existing) timer should not be running */ |
1670 | } |
1671 | |
1672 | /* ---------------------------------------------------------------------- |
1673 | * User interface: print |
1674 | */ |
1675 | |
1676 | static void game_print_size(game_params *params, float *x, float *y) |
1677 | { |
1678 | int print_width, print_height; |
1679 | game_compute_size(params, 800, &print_width, &print_height); |
1680 | *x = print_width / 100.0F; |
1681 | *y = print_height / 100.0F; |
1682 | } |
1683 | |
1684 | static void game_print(drawing *dr, game_state *state, int tilesize) |
1685 | { |
1686 | int const w = state->params.w, h = state->params.h; |
1687 | game_drawstate ds_obj, *ds = &ds_obj; |
1688 | int r, c, i, colour; |
1689 | |
1690 | ds->tilesize = tilesize; |
1691 | |
1692 | colour = print_mono_colour(dr, 1); assert(colour == COL_BACKGROUND); |
1693 | colour = print_mono_colour(dr, 0); assert(colour == COL_GRID); |
1694 | colour = print_mono_colour(dr, 1); assert(colour == COL_ERROR); |
1695 | colour = print_mono_colour(dr, 0); assert(colour == COL_LOWLIGHT); |
1696 | colour = print_mono_colour(dr, 0); assert(colour == NCOLOURS); |
1697 | |
1698 | for (i = r = 0; r < h; ++r) |
1699 | for (c = 0; c < w; ++c, ++i) |
1700 | draw_cell(dr, ds, r, c, |
1701 | makecell(state->grid[i], FALSE, FALSE, FALSE)); |
1702 | |
1703 | print_line_width(dr, 3 * tilesize / 40); |
1704 | draw_rect_outline(dr, BORDER, BORDER, w*TILESIZE, h*TILESIZE, COL_GRID); |
1705 | } |
1706 | |
1707 | /* And that's about it ;-) **************************************************/ |
1708 | |
1709 | #ifdef COMBINED |
1710 | #define thegame range |
1711 | #endif |
1712 | |
1713 | struct game const thegame = { |
1714 | "Range", "games.range", "range", |
1715 | default_params, |
1716 | game_fetch_preset, |
1717 | decode_params, |
1718 | encode_params, |
1719 | free_params, |
1720 | dup_params, |
1721 | TRUE, game_configure, custom_params, |
1722 | validate_params, |
1723 | new_game_desc, |
1724 | validate_desc, |
1725 | new_game, |
1726 | dup_game, |
1727 | free_game, |
1728 | TRUE, solve_game, |
1729 | TRUE, game_can_format_as_text_now, game_text_format, |
1730 | new_ui, |
1731 | free_ui, |
1732 | encode_ui, |
1733 | decode_ui, |
1734 | game_changed_state, |
1735 | interpret_move, |
1736 | execute_move, |
1737 | PREFERRED_TILE_SIZE, game_compute_size, game_set_size, |
1738 | game_colours, |
1739 | game_new_drawstate, |
1740 | game_free_drawstate, |
1741 | game_redraw, |
1742 | game_anim_length, |
1743 | game_flash_length, |
1cea529f |
1744 | game_status, |
e7414d31 |
1745 | TRUE, FALSE, game_print_size, game_print, |
1746 | FALSE, /* wants_statusbar */ |
1747 | FALSE, game_timing_state, |
1748 | 0, /* flags */ |
1749 | }; |