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Couple of missing 'static's.
[sgt/puzzles] / unfinished / group.c
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d8fa223c 1/*
2 * group.c: a Latin-square puzzle, but played with groups' Cayley
3 * tables. That is, you are given a Cayley table of a group with
4 * most elements blank and a few clues, and you must fill it in
5 * so as to preserve the group axioms.
6 *
7 * This is a perfectly playable and fully working puzzle, but I'm
8 * leaving it for the moment in the 'unfinished' directory because
9 * it's just too esoteric (not to mention _hard_) for me to be
10 * comfortable presenting it to the general public as something they
11 * might (implicitly) actually want to play.
12 *
13 * TODO:
14 *
15 * - more solver techniques?
16 * * Inverses: once we know that gh = e, we can immediately
17 * deduce hg = e as well; then for any gx=y we can deduce
18 * hy=x, and for any xg=y we have yh=x.
19 * * Hard-mode associativity: we currently deduce based on
20 * definite numbers in the grid, but we could also winnow
21 * based on _possible_ numbers.
22 * * My overambitious original thoughts included wondering if we
23 * could infer that there must be elements of certain orders
24 * (e.g. a group of order divisible by 5 must contain an
25 * element of order 5), but I think in fact this is probably
26 * silly.
27 *
28 * - a mode which shuffles the identity element into the mix
29 * instead of keeping it clearly shown for you?
30 * * shuffle more fully during table generation
31 * * start clue removal by clearing the identity row and column
32 * completely, or else it'll be totally obvious where it is
33 * * have to print the group elements outside the grid
34 * * new_ui should start the cursor at 0,0 not 1,1, and cursor
35 * should not be constrained to x,y >= 1
36 * * get rid of the COL_IDENTITY highlights
37 * * will we need more checks in check_errors?
38 */
39
40#include <stdio.h>
41#include <stdlib.h>
42#include <string.h>
43#include <assert.h>
44#include <ctype.h>
45#include <math.h>
46
47#include "puzzles.h"
48#include "latin.h"
49
50/*
51 * Difficulty levels. I do some macro ickery here to ensure that my
52 * enum and the various forms of my name list always match up.
53 */
54#define DIFFLIST(A) \
55 A(TRIVIAL,Trivial,NULL,t) \
56 A(NORMAL,Normal,solver_normal,n) \
57 A(HARD,Hard,NULL,h) \
58 A(EXTREME,Extreme,NULL,x) \
59 A(UNREASONABLE,Unreasonable,NULL,u)
60#define ENUM(upper,title,func,lower) DIFF_ ## upper,
61#define TITLE(upper,title,func,lower) #title,
62#define ENCODE(upper,title,func,lower) #lower
63#define CONFIG(upper,title,func,lower) ":" #title
64enum { DIFFLIST(ENUM) DIFFCOUNT };
65static char const *const group_diffnames[] = { DIFFLIST(TITLE) };
66static char const group_diffchars[] = DIFFLIST(ENCODE);
67#define DIFFCONFIG DIFFLIST(CONFIG)
68
69enum {
70 COL_BACKGROUND,
71 COL_IDENTITY,
72 COL_GRID,
73 COL_USER,
74 COL_HIGHLIGHT,
75 COL_ERROR,
76 COL_PENCIL,
77 NCOLOURS
78};
79
80#define FROMCHAR(c) ((c)>='0'&&(c)<='9' ? (c)-'0' : \
81 (c)>='A'&&(c)<='Z' ? (c)-'A'+10 : (c)-'a'+10)
82#define ISCHAR(c) (((c)>='0'&&(c)<='9') || \
83 ((c)>='A'&&(c)<='Z') || ((c)>='a'&&(c)<='z'))
84#define TOCHAR(c) ((c)>=10 ? (c)-10+'a' : (c)+'0')
85
86struct game_params {
87 int w, diff;
88};
89
90struct game_state {
91 game_params par;
92 digit *grid;
93 unsigned char *immutable;
94 int *pencil; /* bitmaps using bits 1<<1..1<<n */
95 int completed, cheated;
96};
97
98static game_params *default_params(void)
99{
100 game_params *ret = snew(game_params);
101
102 ret->w = 6;
103 ret->diff = DIFF_NORMAL;
104
105 return ret;
106}
107
108const static struct game_params group_presets[] = {
109 { 4, DIFF_NORMAL },
110 { 6, DIFF_NORMAL },
111};
112
113static int game_fetch_preset(int i, char **name, game_params **params)
114{
115 game_params *ret;
116 char buf[80];
117
118 if (i < 0 || i >= lenof(group_presets))
119 return FALSE;
120
121 ret = snew(game_params);
122 *ret = group_presets[i]; /* structure copy */
123
124 sprintf(buf, "%dx%d %s", ret->w, ret->w, group_diffnames[ret->diff]);
125
126 *name = dupstr(buf);
127 *params = ret;
128 return TRUE;
129}
130
131static void free_params(game_params *params)
132{
133 sfree(params);
134}
135
136static game_params *dup_params(game_params *params)
137{
138 game_params *ret = snew(game_params);
139 *ret = *params; /* structure copy */
140 return ret;
141}
142
143static void decode_params(game_params *params, char const *string)
144{
145 char const *p = string;
146
147 params->w = atoi(p);
148 while (*p && isdigit((unsigned char)*p)) p++;
149
150 if (*p == 'd') {
151 int i;
152 p++;
153 params->diff = DIFFCOUNT+1; /* ...which is invalid */
154 if (*p) {
155 for (i = 0; i < DIFFCOUNT; i++) {
156 if (*p == group_diffchars[i])
157 params->diff = i;
158 }
159 p++;
160 }
161 }
162}
163
164static char *encode_params(game_params *params, int full)
165{
166 char ret[80];
167
168 sprintf(ret, "%d", params->w);
169 if (full)
170 sprintf(ret + strlen(ret), "d%c", group_diffchars[params->diff]);
171
172 return dupstr(ret);
173}
174
175static config_item *game_configure(game_params *params)
176{
177 config_item *ret;
178 char buf[80];
179
180 ret = snewn(3, config_item);
181
182 ret[0].name = "Grid size";
183 ret[0].type = C_STRING;
184 sprintf(buf, "%d", params->w);
185 ret[0].sval = dupstr(buf);
186 ret[0].ival = 0;
187
188 ret[1].name = "Difficulty";
189 ret[1].type = C_CHOICES;
190 ret[1].sval = DIFFCONFIG;
191 ret[1].ival = params->diff;
192
193 ret[2].name = NULL;
194 ret[2].type = C_END;
195 ret[2].sval = NULL;
196 ret[2].ival = 0;
197
198 return ret;
199}
200
201static game_params *custom_params(config_item *cfg)
202{
203 game_params *ret = snew(game_params);
204
205 ret->w = atoi(cfg[0].sval);
206 ret->diff = cfg[1].ival;
207
208 return ret;
209}
210
211static char *validate_params(game_params *params, int full)
212{
213 if (params->w < 3 || params->w > 31)
214 return "Grid size must be between 3 and 31";
215 if (params->diff >= DIFFCOUNT)
216 return "Unknown difficulty rating";
217 return NULL;
218}
219
220/* ----------------------------------------------------------------------
221 * Solver.
222 */
223
224static int solver_normal(struct latin_solver *solver, void *vctx)
225{
226 int w = solver->o;
227 digit *grid = solver->grid;
228 int i, j, k;
229
230 /*
231 * Deduce using associativity: (ab)c = a(bc).
232 *
233 * So we pick any a,b,c we like; then if we know ab, bc, and
234 * (ab)c we can fill in a(bc).
235 */
236 for (i = 1; i < w; i++)
237 for (j = 1; j < w; j++)
238 for (k = 1; k < w; k++) {
239 if (!grid[i*w+j] || !grid[j*w+k])
240 continue;
241 if (grid[(grid[i*w+j]-1)*w+k] &&
242 !grid[i*w+(grid[j*w+k]-1)]) {
243 int x = grid[j*w+k]-1, y = i;
244 int n = grid[(grid[i*w+j]-1)*w+k];
245#ifdef STANDALONE_SOLVER
246 if (solver_show_working) {
247 printf("%*sassociativity on %d,%d,%d: %d*%d = %d*%d\n",
248 solver_recurse_depth*4, "",
249 i+1, j+1, k+1,
250 grid[i*w+j], k+1, i+1, grid[j*w+k]);
251 printf("%*s placing %d at (%d,%d)\n",
252 solver_recurse_depth*4, "",
253 n, x+1, y+1);
254 }
255#endif
256 if (solver->cube[(x*w+y)*w+n-1]) {
257 latin_solver_place(solver, x, y, n);
258 return 1;
259 } else {
260#ifdef STANDALONE_SOLVER
261 if (solver_show_working)
262 printf("%*s contradiction!\n",
263 solver_recurse_depth*4, "");
264 return -1;
265#endif
266 }
267 }
268 if (!grid[(grid[i*w+j]-1)*w+k] &&
269 grid[i*w+(grid[j*w+k]-1)]) {
270 int x = k, y = grid[i*w+j]-1;
271 int n = grid[i*w+(grid[j*w+k]-1)];
272#ifdef STANDALONE_SOLVER
273 if (solver_show_working) {
274 printf("%*sassociativity on %d,%d,%d: %d*%d = %d*%d\n",
275 solver_recurse_depth*4, "",
276 i+1, j+1, k+1,
277 grid[i*w+j], k+1, i+1, grid[j*w+k]);
278 printf("%*s placing %d at (%d,%d)\n",
279 solver_recurse_depth*4, "",
280 n, x+1, y+1);
281 }
282#endif
283 if (solver->cube[(x*w+y)*w+n-1]) {
284 latin_solver_place(solver, x, y, n);
285 return 1;
286 } else {
287#ifdef STANDALONE_SOLVER
288 if (solver_show_working)
289 printf("%*s contradiction!\n",
290 solver_recurse_depth*4, "");
291 return -1;
292#endif
293 }
294 }
295 }
296
297 return 0;
298}
299
300#define SOLVER(upper,title,func,lower) func,
301static usersolver_t const group_solvers[] = { DIFFLIST(SOLVER) };
302
303static int solver(int w, digit *grid, int maxdiff)
304{
305 int ret;
306
307 ret = latin_solver(grid, w, maxdiff,
308 DIFF_TRIVIAL, DIFF_HARD, DIFF_EXTREME,
309 DIFF_EXTREME, DIFF_UNREASONABLE,
310 group_solvers, NULL, NULL, NULL);
311
312 return ret;
313}
314
315/* ----------------------------------------------------------------------
316 * Grid generation.
317 */
318
319static char *encode_grid(char *desc, digit *grid, int area)
320{
321 int run, i;
322 char *p = desc;
323
324 run = 0;
325 for (i = 0; i <= area; i++) {
326 int n = (i < area ? grid[i] : -1);
327
328 if (!n)
329 run++;
330 else {
331 if (run) {
332 while (run > 0) {
333 int c = 'a' - 1 + run;
334 if (run > 26)
335 c = 'z';
336 *p++ = c;
337 run -= c - ('a' - 1);
338 }
339 } else {
340 /*
341 * If there's a number in the very top left or
342 * bottom right, there's no point putting an
343 * unnecessary _ before or after it.
344 */
345 if (p > desc && n > 0)
346 *p++ = '_';
347 }
348 if (n > 0)
349 p += sprintf(p, "%d", n);
350 run = 0;
351 }
352 }
353 return p;
354}
355
356/* ----- data generated by group.gap begins ----- */
357
358struct group {
359 unsigned long autosize;
360 int order, ngens;
361 const char *gens;
362};
363struct groups {
364 int ngroups;
365 const struct group *groups;
366};
367
368static const struct group groupdata[] = {
369 /* order 2 */
370 {1L, 2, 1, "21"},
371 /* order 3 */
372 {2L, 3, 1, "231"},
373 /* order 4 */
374 {2L, 4, 1, "2341"},
375 {6L, 4, 2, "2143" "3412"},
376 /* order 5 */
377 {4L, 5, 1, "23451"},
378 /* order 6 */
379 {6L, 6, 2, "365214" "214365"},
380 {2L, 6, 1, "436521"},
381 /* order 7 */
382 {6L, 7, 1, "2345671"},
383 /* order 8 */
384 {4L, 8, 1, "23564781"},
385 {8L, 8, 2, "24567183" "57284361"},
386 {8L, 8, 2, "57284361" "21563487"},
387 {24L, 8, 2, "24567183" "38472516"},
388 {168L, 8, 3, "21563487" "35172846" "46718235"},
389 /* order 9 */
390 {6L, 9, 1, "245378691"},
391 {48L, 9, 2, "245178396" "356781924"},
392 /* order 10 */
393 {20L, 10, 2, "3A52749618" "21436587A9"},
394 {4L, 10, 1, "436587A921"},
395 /* order 11 */
396 {10L, 11, 1, "23456789AB1"},
397 /* order 12 */
398 {12L, 12, 2, "7C4BA5832916" "2356179A4BC8"},
399 {4L, 12, 1, "589AB32C4761"},
400 {24L, 12, 2, "256719AB34C8" "6A2B8C574391"},
401 {12L, 12, 2, "7C4BA5832916" "2156349A78CB"},
402 {12L, 12, 2, "649A78C2B153" "794B6C83A512"},
403 /* order 13 */
404 {12L, 13, 1, "23456789ABCD1"},
405 /* order 14 */
406 {42L, 14, 2, "5C7E92B4D6183A" "21436587A9CBED"},
407 {6L, 14, 1, "6587A9CBED2143"},
408 /* order 15 */
409 {8L, 15, 1, "5783AB6DE9F2C41"},
410 /* order 16 */
411 {8L, 16, 1, "DBEG6F1427C3958A"},
412 {96L, 16, 2, "9CB3FE6G54A87D12" "2467891BCDE3F5GA"},
413 {32L, 16, 2, "D98G643FE2C1BA75" "25678AB1CDEF34G9"},
414 {32L, 16, 2, "9613F7CD45A2EGB8" "25678AB1CDEF34G9"},
415 {16L, 16, 2, "DF8G6B39E2C14A75" "2467895BCDEAF1G3"},
416 {16L, 16, 2, "D98G64AFE2C5B371" "2467895BCDEAF1G3"},
417 {32L, 16, 2, "DF8G6439E2C5BA71" "21678345CDE9ABGF"},
418 {16L, 16, 2, "D98G6BAFE2C14375" "74G8EF5B6C2391DA"},
419 {32L, 16, 2, "D92G64AF78C5B3E1" "3C59A7DGB1F8E642"},
420 {192L, 16, 3,
421 "D38G619AE2C45F7B" "25678AB1CDEF34G9" "7BC2EF546G8A91D3"},
422 {64L, 16, 3, "D38G619AE2C45F7B" "CF76GBA92ED54381" "3D19A8G645FE2CB7"},
423 {192L, 16, 3,
424 "9GB3F7DC54A2E618" "25678AB1CDEF34G9" "3D59A2G6B1F78C4E"},
425 {48L, 16, 3, "9G4AFE6C5B327D18" "6A2CD5F378GB19E4" "4795BC8EAF1DG236"},
426 {20160L, 16, 4,
427 "58AB1DE2F34G679C" "21678345CDE9ABGF" "3619A2CD45F78GBE"
428 "4791BC2E3F56G8AD"},
429 /* order 17 */
430 {16L, 17, 1, "56789ABCDEFGH1234"},
431 /* order 18 */
432 {54L, 18, 2, "DB9HFGE17CI5342A86" "215634ABC789FGDEIH"},
433 {6L, 18, 1, "53AB786FG4DECI9H21"},
434 {12L, 18, 2, "53AB782FG1DE6I4HC9" "BEFGH36I5978CA1D24"},
435 {432L, 18, 3,
436 "96E1BCH34FG278I5DA" "EFH36I978BCA1DG245" "215634ABC789FGDEIH"},
437 {48L, 18, 2, "53AB782FG1DE6I4HC9" "64BC89FG2DE1I5H3A7"},
438 /* order 19 */
439 {18L, 19, 1, "56789ABCDEFGHIJ1234"},
440 /* order 20 */
441 {40L, 20, 2, "7K4BI58F29CJ6DG3AH1E" "5129346D78AHBCEKFGIJ"},
442 {8L, 20, 1, "589AC3DEG7HIJB2K4F61"},
443 {20L, 20, 2, "4AJ8HE3CKI7G52B196FD" "5129346D78AHBCEKFGIJ"},
444 {40L, 20, 2, "7K4BI58F29CJ6DG3AH1E" "5329176D4BAH8FEKCJIG"},
445 {24L, 20, 2, "976D4BAH8FEKCJI5G321" "649A78DEBCHIFGK2J153"},
446 /* order 21 */
447 {42L, 21, 2, "9KCJ2FL5I4817B3AE6DHG" "5A8CDBFGEIJH1LK342679"},
448 {12L, 21, 1, "5783AB6DE9GHCJKFL2I41"},
449 /* order 22 */
450 {110L, 22, 2, "5K7M92B4D6F8HAJCLE1G3I" "21436587A9CBEDGFIHKJML"},
451 {10L, 22, 1, "6587A9CBEDGFIHKJML2143"},
452 /* order 23 */
453 {22L, 23, 1, "56789ABCDEFGHIJKLMN1234"},
454 /* order 24 */
455 {24L, 24, 2, "HO5ANGLDBCI9M26KJ1378E4F" "8IEFGJN3KLM2C49AO671BHD5"},
456 {8L, 24, 1, "DH2KL4IN678OA5C9EFGBJ1M3"},
457 {24L, 24, 2, "9FHI25LM6N78BC1ODEGJ34KA" "EAOFM74BJDK69GH5C3LI2N18"},
458 {48L, 24, 2, "HL5ANMO6BCI9G7DEJ132FK48" "8JEFGNC4KLM2I91BO673H5DA"},
459 {24L, 24, 2, "HO5ANGLDBCI9M26KJ1378E4F" "KN8EOCI9FGLDJ13HM2645A7B"},
460 {48L, 24, 2, "HL5ANMO6BCI9G7DEJ132FK48" "21678345DEFG9ABCKLMHIJON"},
461 {48L, 24, 3,
462 "HOBANMLD5JI9G76KC432FE18" "AL5HIGO6BCN3M2DEJ1978K4F"
463 "8JEFGNC4KLM2I91BO673H5DA"},
464 {24L, 24, 3,
465 "HLBANGO65JI9M2DEC4378K1F" "AO5HIMLDBCN3G76KJ192FE48"
466 "KIFEOCN38MLDJ19AG7645H2B"},
467 {16L, 24, 2, "DI7KLCN9FG6OJ4AH2ME5B381" "MBO8FH1JEKG23N45L679ACDI"},
468 {16L, 24, 2, "DI7KLCN9FG6OJ4AH2ME5B381" "IDCN97KLJ4AHFG6O5B32ME18"},
469 {48L, 24, 2, "9LCHI7ODJ43NFGEK5BA2M618" "7CDFGIJ4KL2MN95B6O8AH1E3"},
470 {24L, 24, 2, "LAGODI3JE87KCN9B6M254HF1" "EIL6MCN9GODFA54H87K3J12B"},
471 {24L, 24, 2, "D92KL1HI678O345NEFGABCMJ" "FBOM6NJ37LKE4IHA2GD1C985"},
472 {144L, 24, 3,
473 "HOBANMLD5JI9G76KC432FE18" "AL5HIGO6BCN3M2DEJ1978K4F"
474 "21678345DEFG9ABCKLMHIJON"},
475 {336L, 24, 3,
476 "HKBANFEO5JI98MLDC43G7612" "AE5HI8KLBCN3FGO6J19M2D47"
477 "85EFGABCKLM2HIJ1O67N34D9"},
478 /* order 25 */
479 {20L, 25, 1, "589CDEGHIJ6KLM2ANO4FP71B3"},
480 {480L, 25, 2, "589CDEGHIJ3KLM26NO4AP7FB1" "245789BCDE1GHIJ3KLM6NOAPF"},
481 /* order 26 */
482 {156L, 26, 2,
483 "5O7Q92B4D6F8HAJCLENGPI1K3M" "21436587A9CBEDGFIHKJMLONQP"},
484 {12L, 26, 1, "6587A9CBEDGFIHKJMLONQP2143"},
485 /* order 27 */
486 {18L, 27, 1, "53BC689IJKDE4GHOP7LMANRFQ12"},
487 {108L, 27, 2,
488 "54BC79AIJKEFGH1OPLM2N3RQ68D" "DI2LG5O67Q4NBCREF9A8JKMH1P3"},
489 {432L, 27, 2,
490 "51BC234IJK6789AOPDEFGHRLMNQ" "3E89PLM1GHRB7Q64NKIJFDA5O2C"},
491 {54L, 27, 2,
492 "54BC79AIJKEFGH1OPLM2N3RQ68D" "DR2LNKI67QA8P5OEFH1GBCM34J9"},
493 {11232L, 27, 3,
494 "51BC234IJK6789AOPDEFGHRLMNQ" "3689BDE1GHIJ2LM4N5OP7QACRFK"
495 "479ACEFGH1JKLM2N3OP5Q68RBDI"},
496 /* order 28 */
497 {84L, 28, 2,
498 "7S4BQ58F29CJ6DGNAHKRELO3IP1M" "5129346D78AHBCELFGIPJKMSNOQR"},
499 {12L, 28, 1, "589AC3DEG7HIKBLMOFPQRJ2S4N61"},
500 {84L, 28, 2,
501 "7S4BQ58F29CJ6DGNAHKRELO3IP1M" "5329176D4BAH8FELCJIPGNMSKRQO"},
502 {36L, 28, 2,
503 "976D4BAH8FELCJIPGNMSKRQ5O321" "649A78DEBCHIFGLMJKPQNOS2R153"},
504 /* order 29 */
505 {28L, 29, 1, "56789ABCDEFGHIJKLMNOPQRST1234"},
506 /* order 30 */
507 {24L, 30, 2,
508 "LHQ7NOTDERSA9JK6UGF1PBCM34I285" "BFHIL3NO5Q78RSATDE6UG9JKCM1P24"},
509 {40L, 30, 2,
510 "DU4JOA89PS2GEFT56MKL7BCRQ1HI3N" "BQGHT36MNL78CRS1DEIU54JKOA9P2F"},
511 {120L, 30, 2,
512 "DS4JU589POABEFT2GHKL76MNQ1CR3I" "215634ABC789GHIDEFMNOJKLRSPQUT"},
513 {8L, 30, 1, "HEMNJKCRS9PQIU5FT3OABL782G1D64"},
514 /* order 31 */
515 {30L, 31, 1, "56789ABCDEFGHIJKLMNOPQRSTUV1234"},
516};
517
518static const struct groups groups[] = {
519 {0, NULL}, /* trivial case: 0 */
520 {0, NULL}, /* trivial case: 1 */
521 {1, groupdata + 0}, /* 2 */
522 {1, groupdata + 1}, /* 3 */
523 {2, groupdata + 2}, /* 4 */
524 {1, groupdata + 4}, /* 5 */
525 {2, groupdata + 5}, /* 6 */
526 {1, groupdata + 7}, /* 7 */
527 {5, groupdata + 8}, /* 8 */
528 {2, groupdata + 13}, /* 9 */
529 {2, groupdata + 15}, /* 10 */
530 {1, groupdata + 17}, /* 11 */
531 {5, groupdata + 18}, /* 12 */
532 {1, groupdata + 23}, /* 13 */
533 {2, groupdata + 24}, /* 14 */
534 {1, groupdata + 26}, /* 15 */
535 {14, groupdata + 27}, /* 16 */
536 {1, groupdata + 41}, /* 17 */
537 {5, groupdata + 42}, /* 18 */
538 {1, groupdata + 47}, /* 19 */
539 {5, groupdata + 48}, /* 20 */
540 {2, groupdata + 53}, /* 21 */
541 {2, groupdata + 55}, /* 22 */
542 {1, groupdata + 57}, /* 23 */
543 {15, groupdata + 58}, /* 24 */
544 {2, groupdata + 73}, /* 25 */
545 {2, groupdata + 75}, /* 26 */
546 {5, groupdata + 77}, /* 27 */
547 {4, groupdata + 82}, /* 28 */
548 {1, groupdata + 86}, /* 29 */
549 {4, groupdata + 87}, /* 30 */
550 {1, groupdata + 91}, /* 31 */
551};
552
553/* ----- data generated by group.gap ends ----- */
554
555static char *new_game_desc(game_params *params, random_state *rs,
556 char **aux, int interactive)
557{
558 int w = params->w, a = w*w;
559 digit *grid, *soln, *soln2;
560 int *indices;
561 int i, j, k, qh, qt;
562 int diff = params->diff;
563 const struct group *group;
564 char *desc, *p;
565
566 /*
567 * Difficulty exceptions: some combinations of size and
568 * difficulty cannot be satisfied, because all puzzles of at
569 * most that difficulty are actually even easier.
570 *
571 * Remember to re-test this whenever a change is made to the
572 * solver logic!
573 *
574 * I tested it using the following shell command:
575
576for d in t n h x u; do
577 for i in {3..9}; do
578 echo ./group --generate 1 ${i}d${d}
579 perl -e 'alarm 30; exec @ARGV' ./group --generate 5 ${i}d${d} >/dev/null \
580 || echo broken
581 done
582done
583
584 * Of course, it's better to do that after taking the exceptions
585 * _out_, so as to detect exceptions that should be removed as
586 * well as those which should be added.
587 */
588 if (w <= 9 && diff == DIFF_EXTREME)
589 diff--;
590 if (w <= 6 && diff == DIFF_HARD)
591 diff--;
592 if (w <= 4 && diff > DIFF_TRIVIAL)
593 diff = DIFF_TRIVIAL;
594
595 grid = snewn(a, digit);
596 soln = snewn(a, digit);
597 soln2 = snewn(a, digit);
598 indices = snewn(a, int);
599
600 while (1) {
601 /*
602 * Construct a valid group table, by picking a group from
603 * the above data table, decompressing it into a full
604 * representation by BFS, and then randomly permuting its
605 * non-identity elements.
606 *
607 * We build the canonical table in 'soln' (and use 'grid' as
608 * our BFS queue), then transfer the table into 'grid'
609 * having shuffled the rows.
610 */
611 assert(w >= 2);
612 assert(w < lenof(groups));
613 group = groups[w].groups + random_upto(rs, groups[w].ngroups);
614 assert(group->order == w);
615 memset(soln, 0, a);
616 for (i = 0; i < w; i++)
617 soln[i] = i+1;
618 qh = qt = 0;
619 grid[qt++] = 1;
620 while (qh < qt) {
621 digit *row, *newrow;
622
623 i = grid[qh++];
624 row = soln + (i-1)*w;
625
626 for (j = 0; j < group->ngens; j++) {
627 int nri;
628 const char *gen = group->gens + j*w;
629
630 /*
631 * Apply each group generator to row, constructing a
632 * new row.
633 */
634 nri = FROMCHAR(gen[row[0]-1]); /* which row is it? */
635 newrow = soln + (nri-1)*w;
636 if (!newrow[0]) { /* not done yet */
637 for (k = 0; k < w; k++)
638 newrow[k] = FROMCHAR(gen[row[k]-1]);
639 grid[qt++] = nri;
640 }
641 }
642 }
643 /* That's got the canonical table. Now shuffle it. */
644 for (i = 0; i < w; i++)
645 grid[i] = i+1;
646 shuffle(grid+1, w-1, sizeof(*grid), rs);
647 for (i = 1; i < w; i++)
648 for (j = 0; j < w; j++)
649 grid[(grid[i]-1)*w+(grid[j]-1)] = grid[soln[i*w+j]-1];
650 for (i = 0; i < w; i++)
651 grid[i] = i+1;
652
653 /*
654 * Remove entries one by one while the puzzle is still
655 * soluble at the appropriate difficulty level.
656 */
657 memcpy(soln, grid, a);
658
659 k = 0;
660 for (i = 1; i < w; i++)
661 for (j = 1; j < w; j++)
662 indices[k++] = i*w+j;
663 shuffle(indices, k, sizeof(indices), rs);
664
665 for (i = 0; i < k; i++) {
666 memcpy(soln2, grid, a);
667 soln2[indices[i]] = 0;
668 if (solver(w, soln2, diff) <= diff)
669 grid[indices[i]] = 0;
670 }
671
672 /*
673 * Make sure the puzzle isn't too easy.
674 */
675 if (diff > 0) {
676 memcpy(soln2, grid, a);
677 if (solver(w, soln2, diff-1) < diff)
678 continue; /* go round and try again */
679 }
680
681 /*
682 * Done.
683 */
684 break;
685 }
686
687 /*
688 * Encode the puzzle description.
689 */
690 desc = snewn(a*20, char);
691 p = encode_grid(desc, grid, a);
692 *p++ = '\0';
693 desc = sresize(desc, p - desc, char);
694
695 /*
696 * Encode the solution.
697 */
698 *aux = snewn(a+2, char);
699 (*aux)[0] = 'S';
700 for (i = 0; i < a; i++)
701 (*aux)[i+1] = TOCHAR(soln[i]);
702 (*aux)[a+1] = '\0';
703
704 sfree(grid);
705 sfree(soln);
706 sfree(soln2);
707 sfree(indices);
708
709 return desc;
710}
711
712/* ----------------------------------------------------------------------
713 * Gameplay.
714 */
715
716static char *validate_grid_desc(const char **pdesc, int range, int area)
717{
718 const char *desc = *pdesc;
719 int squares = 0;
720 while (*desc && *desc != ',') {
721 int n = *desc++;
722 if (n >= 'a' && n <= 'z') {
723 squares += n - 'a' + 1;
724 } else if (n == '_') {
725 /* do nothing */;
726 } else if (n > '0' && n <= '9') {
727 int val = atoi(desc-1);
728 if (val < 1 || val > range)
729 return "Out-of-range number in game description";
730 squares++;
731 while (*desc >= '0' && *desc <= '9')
732 desc++;
733 } else
734 return "Invalid character in game description";
735 }
736
737 if (squares < area)
738 return "Not enough data to fill grid";
739
740 if (squares > area)
741 return "Too much data to fit in grid";
742 *pdesc = desc;
743 return NULL;
744}
745
746static char *validate_desc(game_params *params, char *desc)
747{
748 int w = params->w, a = w*w;
749 const char *p = desc;
750
751 return validate_grid_desc(&p, w, a);
752}
753
754static char *spec_to_grid(char *desc, digit *grid, int area)
755{
756 int i = 0;
757 while (*desc && *desc != ',') {
758 int n = *desc++;
759 if (n >= 'a' && n <= 'z') {
760 int run = n - 'a' + 1;
761 assert(i + run <= area);
762 while (run-- > 0)
763 grid[i++] = 0;
764 } else if (n == '_') {
765 /* do nothing */;
766 } else if (n > '0' && n <= '9') {
767 assert(i < area);
768 grid[i++] = atoi(desc-1);
769 while (*desc >= '0' && *desc <= '9')
770 desc++;
771 } else {
772 assert(!"We can't get here");
773 }
774 }
775 assert(i == area);
776 return desc;
777}
778
779static game_state *new_game(midend *me, game_params *params, char *desc)
780{
781 int w = params->w, a = w*w;
782 game_state *state = snew(game_state);
783 int i;
784
785 state->par = *params; /* structure copy */
786 state->grid = snewn(a, digit);
787 state->immutable = snewn(a, unsigned char);
788 state->pencil = snewn(a, int);
789 for (i = 0; i < a; i++) {
790 state->grid[i] = 0;
791 state->immutable[i] = 0;
792 state->pencil[i] = 0;
793 }
794
795 desc = spec_to_grid(desc, state->grid, a);
796 for (i = 0; i < a; i++)
797 if (state->grid[i] != 0)
798 state->immutable[i] = TRUE;
799
800 state->completed = state->cheated = FALSE;
801
802 return state;
803}
804
805static game_state *dup_game(game_state *state)
806{
807 int w = state->par.w, a = w*w;
808 game_state *ret = snew(game_state);
809
810 ret->par = state->par; /* structure copy */
811
812 ret->grid = snewn(a, digit);
813 ret->immutable = snewn(a, unsigned char);
814 ret->pencil = snewn(a, int);
815 memcpy(ret->grid, state->grid, a*sizeof(digit));
816 memcpy(ret->immutable, state->immutable, a*sizeof(unsigned char));
817 memcpy(ret->pencil, state->pencil, a*sizeof(int));
818
819 ret->completed = state->completed;
820 ret->cheated = state->cheated;
821
822 return ret;
823}
824
825static void free_game(game_state *state)
826{
827 sfree(state->grid);
828 sfree(state->immutable);
829 sfree(state->pencil);
830 sfree(state);
831}
832
833static char *solve_game(game_state *state, game_state *currstate,
834 char *aux, char **error)
835{
836 int w = state->par.w, a = w*w;
837 int i, ret;
838 digit *soln;
839 char *out;
840
841 if (aux)
842 return dupstr(aux);
843
844 soln = snewn(a, digit);
845 memcpy(soln, state->grid, a*sizeof(digit));
846
847 ret = solver(w, soln, DIFFCOUNT-1);
848
849 if (ret == diff_impossible) {
850 *error = "No solution exists for this puzzle";
851 out = NULL;
852 } else if (ret == diff_ambiguous) {
853 *error = "Multiple solutions exist for this puzzle";
854 out = NULL;
855 } else {
856 out = snewn(a+2, char);
857 out[0] = 'S';
858 for (i = 0; i < a; i++)
859 out[i+1] = TOCHAR(soln[i]);
860 out[a+1] = '\0';
861 }
862
863 sfree(soln);
864 return out;
865}
866
867static int game_can_format_as_text_now(game_params *params)
868{
869 return TRUE;
870}
871
872static char *game_text_format(game_state *state)
873{
874 int w = state->par.w;
875 int x, y;
876 char *ret, *p, ch;
877
878 ret = snewn(2*w*w+1, char); /* leave room for terminating NUL */
879
880 p = ret;
881 for (y = 0; y < w; y++) {
882 for (x = 0; x < w; x++) {
883 digit d = state->grid[y*w+x];
884
885 if (d == 0) {
886 ch = '.';
887 } else {
888 ch = TOCHAR(d);
889 }
890
891 *p++ = ch;
892 if (x == w-1) {
893 *p++ = '\n';
894 } else {
895 *p++ = ' ';
896 }
897 }
898 }
899
900 assert(p - ret == 2*w*w);
901 *p = '\0';
902 return ret;
903}
904
905struct game_ui {
906 /*
907 * These are the coordinates of the currently highlighted
908 * square on the grid, if hshow = 1.
909 */
910 int hx, hy;
911 /*
912 * This indicates whether the current highlight is a
913 * pencil-mark one or a real one.
914 */
915 int hpencil;
916 /*
917 * This indicates whether or not we're showing the highlight
918 * (used to be hx = hy = -1); important so that when we're
919 * using the cursor keys it doesn't keep coming back at a
920 * fixed position. When hshow = 1, pressing a valid number
921 * or letter key or Space will enter that number or letter in the grid.
922 */
923 int hshow;
924 /*
925 * This indicates whether we're using the highlight as a cursor;
926 * it means that it doesn't vanish on a keypress, and that it is
927 * allowed on immutable squares.
928 */
929 int hcursor;
930};
931
932static game_ui *new_ui(game_state *state)
933{
934 game_ui *ui = snew(game_ui);
935
936 ui->hx = ui->hy = 1;
937 ui->hpencil = ui->hshow = ui->hcursor = 0;
938
939 return ui;
940}
941
942static void free_ui(game_ui *ui)
943{
944 sfree(ui);
945}
946
947static char *encode_ui(game_ui *ui)
948{
949 return NULL;
950}
951
952static void decode_ui(game_ui *ui, char *encoding)
953{
954}
955
956static void game_changed_state(game_ui *ui, game_state *oldstate,
957 game_state *newstate)
958{
959 int w = newstate->par.w;
960 /*
961 * We prevent pencil-mode highlighting of a filled square, unless
962 * we're using the cursor keys. So if the user has just filled in
963 * a square which we had a pencil-mode highlight in (by Undo, or
964 * by Redo, or by Solve), then we cancel the highlight.
965 */
966 if (ui->hshow && ui->hpencil && !ui->hcursor &&
967 newstate->grid[ui->hy * w + ui->hx] != 0) {
968 ui->hshow = 0;
969 }
970}
971
972#define PREFERRED_TILESIZE 48
973#define TILESIZE (ds->tilesize)
974#define BORDER (TILESIZE / 2)
975#define GRIDEXTRA max((TILESIZE / 32),1)
976#define COORD(x) ((x)*TILESIZE + BORDER)
977#define FROMCOORD(x) (((x)+(TILESIZE-BORDER)) / TILESIZE - 1)
978
979#define FLASH_TIME 0.4F
980
981#define DF_HIGHLIGHT 0x0400
982#define DF_HIGHLIGHT_PENCIL 0x0200
983#define DF_IMMUTABLE 0x0100
984#define DF_DIGIT_MASK 0x001F
985
986#define EF_DIGIT_SHIFT 5
987#define EF_DIGIT_MASK ((1 << EF_DIGIT_SHIFT) - 1)
988#define EF_LEFT_SHIFT 0
989#define EF_RIGHT_SHIFT (3*EF_DIGIT_SHIFT)
990#define EF_LEFT_MASK ((1UL << (3*EF_DIGIT_SHIFT)) - 1UL)
991#define EF_RIGHT_MASK (EF_LEFT_MASK << EF_RIGHT_SHIFT)
992#define EF_LATIN (1UL << (6*EF_DIGIT_SHIFT))
993
994struct game_drawstate {
995 int w, tilesize;
996 int started;
997 long *tiles, *pencil, *errors;
998 long *errtmp;
999};
1000
1001static int check_errors(game_state *state, long *errors)
1002{
1003 int w = state->par.w, a = w*w;
1004 digit *grid = state->grid;
1005 int i, j, k, x, y, errs = FALSE;
1006
1007 if (errors)
1008 for (i = 0; i < a; i++)
1009 errors[i] = 0;
1010
1011 for (y = 0; y < w; y++) {
1012 unsigned long mask = 0, errmask = 0;
1013 for (x = 0; x < w; x++) {
1014 unsigned long bit = 1UL << grid[y*w+x];
1015 errmask |= (mask & bit);
1016 mask |= bit;
1017 }
1018
1019 if (mask != (1 << (w+1)) - (1 << 1)) {
1020 errs = TRUE;
1021 errmask &= ~1UL;
1022 if (errors) {
1023 for (x = 0; x < w; x++)
1024 if (errmask & (1UL << grid[y*w+x]))
1025 errors[y*w+x] |= EF_LATIN;
1026 }
1027 }
1028 }
1029
1030 for (x = 0; x < w; x++) {
1031 unsigned long mask = 0, errmask = 0;
1032 for (y = 0; y < w; y++) {
1033 unsigned long bit = 1UL << grid[y*w+x];
1034 errmask |= (mask & bit);
1035 mask |= bit;
1036 }
1037
1038 if (mask != (1 << (w+1)) - (1 << 1)) {
1039 errs = TRUE;
1040 errmask &= ~1UL;
1041 if (errors) {
1042 for (y = 0; y < w; y++)
1043 if (errmask & (1UL << grid[y*w+x]))
1044 errors[y*w+x] |= EF_LATIN;
1045 }
1046 }
1047 }
1048
1049 for (i = 1; i < w; i++)
1050 for (j = 1; j < w; j++)
1051 for (k = 1; k < w; k++)
1052 if (grid[i*w+j] && grid[j*w+k] &&
1053 grid[(grid[i*w+j]-1)*w+k] &&
1054 grid[i*w+(grid[j*w+k]-1)] &&
1055 grid[(grid[i*w+j]-1)*w+k] != grid[i*w+(grid[j*w+k]-1)]) {
1056 if (errors) {
1057 int a = i+1, b = j+1, c = k+1;
1058 int ab = grid[i*w+j], bc = grid[j*w+k];
1059 int left = (ab-1)*w+(c-1), right = (a-1)*w+(bc-1);
1060 /*
1061 * If the appropriate error slot is already
1062 * used for one of the squares, we don't
1063 * fill either of them.
1064 */
1065 if (!(errors[left] & EF_LEFT_MASK) &&
1066 !(errors[right] & EF_RIGHT_MASK)) {
1067 long err;
1068 err = a;
1069 err = (err << EF_DIGIT_SHIFT) | b;
1070 err = (err << EF_DIGIT_SHIFT) | c;
1071 errors[left] |= err << EF_LEFT_SHIFT;
1072 errors[right] |= err << EF_RIGHT_SHIFT;
1073 }
1074 }
1075 errs = TRUE;
1076 }
1077
1078 return errs;
1079}
1080
1081static char *interpret_move(game_state *state, game_ui *ui, game_drawstate *ds,
1082 int x, int y, int button)
1083{
1084 int w = state->par.w;
1085 int tx, ty;
1086 char buf[80];
1087
1088 button &= ~MOD_MASK;
1089
1090 tx = FROMCOORD(x);
1091 ty = FROMCOORD(y);
1092
1093 if (tx > 0 && tx < w && ty > 0 && ty < w) {
1094 if (button == LEFT_BUTTON) {
1095 if (tx == ui->hx && ty == ui->hy &&
1096 ui->hshow && ui->hpencil == 0) {
1097 ui->hshow = 0;
1098 } else {
1099 ui->hx = tx;
1100 ui->hy = ty;
1101 ui->hshow = !state->immutable[ty*w+tx];
1102 ui->hpencil = 0;
1103 }
1104 ui->hcursor = 0;
1105 return ""; /* UI activity occurred */
1106 }
1107 if (button == RIGHT_BUTTON) {
1108 /*
1109 * Pencil-mode highlighting for non filled squares.
1110 */
1111 if (state->grid[ty*w+tx] == 0) {
1112 if (tx == ui->hx && ty == ui->hy &&
1113 ui->hshow && ui->hpencil) {
1114 ui->hshow = 0;
1115 } else {
1116 ui->hpencil = 1;
1117 ui->hx = tx;
1118 ui->hy = ty;
1119 ui->hshow = 1;
1120 }
1121 } else {
1122 ui->hshow = 0;
1123 }
1124 ui->hcursor = 0;
1125 return ""; /* UI activity occurred */
1126 }
1127 }
1128 if (IS_CURSOR_MOVE(button)) {
1129 ui->hx--; ui->hy--;
1130 move_cursor(button, &ui->hx, &ui->hy, w-1, w-1, 0);
1131 ui->hx++; ui->hy++;
1132 ui->hshow = ui->hcursor = 1;
1133 return "";
1134 }
1135 if (ui->hshow &&
1136 (button == CURSOR_SELECT)) {
1137 ui->hpencil = 1 - ui->hpencil;
1138 ui->hcursor = 1;
1139 return "";
1140 }
1141
1142 if (ui->hshow &&
1143 ((ISCHAR(button) && FROMCHAR(button) <= w) ||
1144 button == CURSOR_SELECT2 || button == '\b')) {
1145 int n = FROMCHAR(button);
1146 if (button == CURSOR_SELECT2 || button == '\b')
1147 n = 0;
1148
1149 /*
1150 * Can't make pencil marks in a filled square. This can only
1151 * become highlighted if we're using cursor keys.
1152 */
1153 if (ui->hpencil && state->grid[ui->hy*w+ui->hx])
1154 return NULL;
1155
1156 /*
1157 * Can't do anything to an immutable square.
1158 */
1159 if (state->immutable[ui->hy*w+ui->hx])
1160 return NULL;
1161
1162 sprintf(buf, "%c%d,%d,%d",
1163 (char)(ui->hpencil && n > 0 ? 'P' : 'R'), ui->hx, ui->hy, n);
1164
1165 if (!ui->hcursor) ui->hshow = 0;
1166
1167 return dupstr(buf);
1168 }
1169
1170 if (button == 'M' || button == 'm')
1171 return dupstr("M");
1172
1173 return NULL;
1174}
1175
1176static game_state *execute_move(game_state *from, char *move)
1177{
1178 int w = from->par.w, a = w*w;
1179 game_state *ret;
1180 int x, y, i, n;
1181
1182 if (move[0] == 'S') {
1183 ret = dup_game(from);
1184 ret->completed = ret->cheated = TRUE;
1185
1186 for (i = 0; i < a; i++) {
1187 if (!ISCHAR(move[i+1]) || FROMCHAR(move[i+1]) > w) {
1188 free_game(ret);
1189 return NULL;
1190 }
1191 ret->grid[i] = FROMCHAR(move[i+1]);
1192 ret->pencil[i] = 0;
1193 }
1194
1195 if (move[a+1] != '\0') {
1196 free_game(ret);
1197 return NULL;
1198 }
1199
1200 return ret;
1201 } else if ((move[0] == 'P' || move[0] == 'R') &&
1202 sscanf(move+1, "%d,%d,%d", &x, &y, &n) == 3 &&
1203 x >= 0 && x < w && y >= 0 && y < w && n >= 0 && n <= w) {
1204 if (from->immutable[y*w+x])
1205 return NULL;
1206
1207 ret = dup_game(from);
1208 if (move[0] == 'P' && n > 0) {
1209 ret->pencil[y*w+x] ^= 1 << n;
1210 } else {
1211 ret->grid[y*w+x] = n;
1212 ret->pencil[y*w+x] = 0;
1213
1214 if (!ret->completed && !check_errors(ret, NULL))
1215 ret->completed = TRUE;
1216 }
1217 return ret;
1218 } else if (move[0] == 'M') {
1219 /*
1220 * Fill in absolutely all pencil marks everywhere. (I
1221 * wouldn't use this for actual play, but it's a handy
1222 * starting point when following through a set of
1223 * diagnostics output by the standalone solver.)
1224 */
1225 ret = dup_game(from);
1226 for (i = 0; i < a; i++) {
1227 if (!ret->grid[i])
1228 ret->pencil[i] = (1 << (w+1)) - (1 << 1);
1229 }
1230 return ret;
1231 } else
1232 return NULL; /* couldn't parse move string */
1233}
1234
1235/* ----------------------------------------------------------------------
1236 * Drawing routines.
1237 */
1238
1239#define SIZE(w) ((w) * TILESIZE + 2*BORDER)
1240
1241static void game_compute_size(game_params *params, int tilesize,
1242 int *x, int *y)
1243{
1244 /* Ick: fake up `ds->tilesize' for macro expansion purposes */
1245 struct { int tilesize; } ads, *ds = &ads;
1246 ads.tilesize = tilesize;
1247
1248 *x = *y = SIZE(params->w);
1249}
1250
1251static void game_set_size(drawing *dr, game_drawstate *ds,
1252 game_params *params, int tilesize)
1253{
1254 ds->tilesize = tilesize;
1255}
1256
1257static float *game_colours(frontend *fe, int *ncolours)
1258{
1259 float *ret = snewn(3 * NCOLOURS, float);
1260
1261 frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]);
1262
1263 ret[COL_GRID * 3 + 0] = 0.0F;
1264 ret[COL_GRID * 3 + 1] = 0.0F;
1265 ret[COL_GRID * 3 + 2] = 0.0F;
1266
1267 ret[COL_IDENTITY * 3 + 0] = 0.89F * ret[COL_BACKGROUND * 3 + 0];
1268 ret[COL_IDENTITY * 3 + 1] = 0.89F * ret[COL_BACKGROUND * 3 + 1];
1269 ret[COL_IDENTITY * 3 + 2] = 0.89F * ret[COL_BACKGROUND * 3 + 2];
1270
1271 ret[COL_USER * 3 + 0] = 0.0F;
1272 ret[COL_USER * 3 + 1] = 0.6F * ret[COL_BACKGROUND * 3 + 1];
1273 ret[COL_USER * 3 + 2] = 0.0F;
1274
1275 ret[COL_HIGHLIGHT * 3 + 0] = 0.78F * ret[COL_BACKGROUND * 3 + 0];
1276 ret[COL_HIGHLIGHT * 3 + 1] = 0.78F * ret[COL_BACKGROUND * 3 + 1];
1277 ret[COL_HIGHLIGHT * 3 + 2] = 0.78F * ret[COL_BACKGROUND * 3 + 2];
1278
1279 ret[COL_ERROR * 3 + 0] = 1.0F;
1280 ret[COL_ERROR * 3 + 1] = 0.0F;
1281 ret[COL_ERROR * 3 + 2] = 0.0F;
1282
1283 ret[COL_PENCIL * 3 + 0] = 0.5F * ret[COL_BACKGROUND * 3 + 0];
1284 ret[COL_PENCIL * 3 + 1] = 0.5F * ret[COL_BACKGROUND * 3 + 1];
1285 ret[COL_PENCIL * 3 + 2] = ret[COL_BACKGROUND * 3 + 2];
1286
1287 *ncolours = NCOLOURS;
1288 return ret;
1289}
1290
1291static game_drawstate *game_new_drawstate(drawing *dr, game_state *state)
1292{
1293 int w = state->par.w, a = w*w;
1294 struct game_drawstate *ds = snew(struct game_drawstate);
1295 int i;
1296
1297 ds->w = w;
1298 ds->tilesize = 0;
1299 ds->started = FALSE;
1300 ds->tiles = snewn(a, long);
1301 ds->pencil = snewn(a, long);
1302 ds->errors = snewn(a, long);
1303 for (i = 0; i < a; i++)
1304 ds->tiles[i] = ds->pencil[i] = -1;
1305 ds->errtmp = snewn(a, long);
1306
1307 return ds;
1308}
1309
1310static void game_free_drawstate(drawing *dr, game_drawstate *ds)
1311{
1312 sfree(ds->tiles);
1313 sfree(ds->pencil);
1314 sfree(ds->errors);
1315 sfree(ds->errtmp);
1316 sfree(ds);
1317}
1318
d2cfd12c 1319static void draw_tile(drawing *dr, game_drawstate *ds, int x, int y, long tile,
1320 long pencil, long error)
d8fa223c 1321{
1322 int w = ds->w /* , a = w*w */;
1323 int tx, ty, tw, th;
1324 int cx, cy, cw, ch;
1325 char str[64];
1326
1327 tx = BORDER + x * TILESIZE + 1;
1328 ty = BORDER + y * TILESIZE + 1;
1329
1330 cx = tx;
1331 cy = ty;
1332 cw = tw = TILESIZE-1;
1333 ch = th = TILESIZE-1;
1334
1335 clip(dr, cx, cy, cw, ch);
1336
1337 /* background needs erasing */
1338 draw_rect(dr, cx, cy, cw, ch,
1339 (tile & DF_HIGHLIGHT) ? COL_HIGHLIGHT :
1340 (x == 0 || y == 0) ? COL_IDENTITY : COL_BACKGROUND);
1341
1342 /* pencil-mode highlight */
1343 if (tile & DF_HIGHLIGHT_PENCIL) {
1344 int coords[6];
1345 coords[0] = cx;
1346 coords[1] = cy;
1347 coords[2] = cx+cw/2;
1348 coords[3] = cy;
1349 coords[4] = cx;
1350 coords[5] = cy+ch/2;
1351 draw_polygon(dr, coords, 3, COL_HIGHLIGHT, COL_HIGHLIGHT);
1352 }
1353
1354 /* new number needs drawing? */
1355 if (tile & DF_DIGIT_MASK) {
1356 str[1] = '\0';
1357 str[0] = TOCHAR(tile & DF_DIGIT_MASK);
1358 draw_text(dr, tx + TILESIZE/2, ty + TILESIZE/2,
1359 FONT_VARIABLE, TILESIZE/2, ALIGN_VCENTRE | ALIGN_HCENTRE,
1360 (error & EF_LATIN) ? COL_ERROR :
1361 (tile & DF_IMMUTABLE) ? COL_GRID : COL_USER, str);
1362
1363 if (error & EF_LEFT_MASK) {
1364 int a = (error >> (EF_LEFT_SHIFT+2*EF_DIGIT_SHIFT))&EF_DIGIT_MASK;
1365 int b = (error >> (EF_LEFT_SHIFT+1*EF_DIGIT_SHIFT))&EF_DIGIT_MASK;
1366 int c = (error >> (EF_LEFT_SHIFT ))&EF_DIGIT_MASK;
1367 char buf[10];
1368 sprintf(buf, "(%c%c)%c", TOCHAR(a), TOCHAR(b), TOCHAR(c));
1369 draw_text(dr, tx + TILESIZE/2, ty + TILESIZE/6,
1370 FONT_VARIABLE, TILESIZE/6, ALIGN_VCENTRE | ALIGN_HCENTRE,
1371 COL_ERROR, buf);
1372 }
1373 if (error & EF_RIGHT_MASK) {
1374 int a = (error >> (EF_RIGHT_SHIFT+2*EF_DIGIT_SHIFT))&EF_DIGIT_MASK;
1375 int b = (error >> (EF_RIGHT_SHIFT+1*EF_DIGIT_SHIFT))&EF_DIGIT_MASK;
1376 int c = (error >> (EF_RIGHT_SHIFT ))&EF_DIGIT_MASK;
1377 char buf[10];
1378 sprintf(buf, "%c(%c%c)", TOCHAR(a), TOCHAR(b), TOCHAR(c));
1379 draw_text(dr, tx + TILESIZE/2, ty + TILESIZE - TILESIZE/6,
1380 FONT_VARIABLE, TILESIZE/6, ALIGN_VCENTRE | ALIGN_HCENTRE,
1381 COL_ERROR, buf);
1382 }
1383 } else {
1384 int i, j, npencil;
1385 int pl, pr, pt, pb;
1386 float bestsize;
1387 int pw, ph, minph, pbest, fontsize;
1388
1389 /* Count the pencil marks required. */
1390 for (i = 1, npencil = 0; i <= w; i++)
1391 if (pencil & (1 << i))
1392 npencil++;
1393 if (npencil) {
1394
1395 minph = 2;
1396
1397 /*
1398 * Determine the bounding rectangle within which we're going
1399 * to put the pencil marks.
1400 */
1401 /* Start with the whole square */
1402 pl = tx + GRIDEXTRA;
1403 pr = pl + TILESIZE - GRIDEXTRA;
1404 pt = ty + GRIDEXTRA;
1405 pb = pt + TILESIZE - GRIDEXTRA;
1406
1407 /*
1408 * We arrange our pencil marks in a grid layout, with
1409 * the number of rows and columns adjusted to allow the
1410 * maximum font size.
1411 *
1412 * So now we work out what the grid size ought to be.
1413 */
1414 bestsize = 0.0;
1415 pbest = 0;
1416 /* Minimum */
1417 for (pw = 3; pw < max(npencil,4); pw++) {
1418 float fw, fh, fs;
1419
1420 ph = (npencil + pw - 1) / pw;
1421 ph = max(ph, minph);
1422 fw = (pr - pl) / (float)pw;
1423 fh = (pb - pt) / (float)ph;
1424 fs = min(fw, fh);
1425 if (fs > bestsize) {
1426 bestsize = fs;
1427 pbest = pw;
1428 }
1429 }
1430 assert(pbest > 0);
1431 pw = pbest;
1432 ph = (npencil + pw - 1) / pw;
1433 ph = max(ph, minph);
1434
1435 /*
1436 * Now we've got our grid dimensions, work out the pixel
1437 * size of a grid element, and round it to the nearest
1438 * pixel. (We don't want rounding errors to make the
1439 * grid look uneven at low pixel sizes.)
1440 */
1441 fontsize = min((pr - pl) / pw, (pb - pt) / ph);
1442
1443 /*
1444 * Centre the resulting figure in the square.
1445 */
1446 pl = tx + (TILESIZE - fontsize * pw) / 2;
1447 pt = ty + (TILESIZE - fontsize * ph) / 2;
1448
1449 /*
1450 * Now actually draw the pencil marks.
1451 */
1452 for (i = 1, j = 0; i <= w; i++)
1453 if (pencil & (1 << i)) {
1454 int dx = j % pw, dy = j / pw;
1455
1456 str[1] = '\0';
1457 str[0] = TOCHAR(i);
1458 draw_text(dr, pl + fontsize * (2*dx+1) / 2,
1459 pt + fontsize * (2*dy+1) / 2,
1460 FONT_VARIABLE, fontsize,
1461 ALIGN_VCENTRE | ALIGN_HCENTRE, COL_PENCIL, str);
1462 j++;
1463 }
1464 }
1465 }
1466
1467 unclip(dr);
1468
1469 draw_update(dr, cx, cy, cw, ch);
1470}
1471
1472static void game_redraw(drawing *dr, game_drawstate *ds, game_state *oldstate,
1473 game_state *state, int dir, game_ui *ui,
1474 float animtime, float flashtime)
1475{
1476 int w = state->par.w /*, a = w*w */;
1477 int x, y;
1478
1479 if (!ds->started) {
1480 /*
1481 * The initial contents of the window are not guaranteed and
1482 * can vary with front ends. To be on the safe side, all
1483 * games should start by drawing a big background-colour
1484 * rectangle covering the whole window.
1485 */
1486 draw_rect(dr, 0, 0, SIZE(w), SIZE(w), COL_BACKGROUND);
1487
1488 /*
1489 * Big containing rectangle.
1490 */
1491 draw_rect(dr, COORD(0) - GRIDEXTRA, COORD(0) - GRIDEXTRA,
1492 w*TILESIZE+1+GRIDEXTRA*2, w*TILESIZE+1+GRIDEXTRA*2,
1493 COL_GRID);
1494
1495 draw_update(dr, 0, 0, SIZE(w), SIZE(w));
1496
1497 ds->started = TRUE;
1498 }
1499
1500 check_errors(state, ds->errtmp);
1501
1502 for (y = 0; y < w; y++) {
1503 for (x = 0; x < w; x++) {
1504 long tile = 0L, pencil = 0L, error;
1505
1506 if (state->grid[y*w+x])
1507 tile = state->grid[y*w+x];
1508 else
1509 pencil = (long)state->pencil[y*w+x];
1510
1511 if (state->immutable[y*w+x])
1512 tile |= DF_IMMUTABLE;
1513
1514 if (ui->hshow && ui->hx == x && ui->hy == y)
1515 tile |= (ui->hpencil ? DF_HIGHLIGHT_PENCIL : DF_HIGHLIGHT);
1516
1517 if (flashtime > 0 &&
1518 (flashtime <= FLASH_TIME/3 ||
1519 flashtime >= FLASH_TIME*2/3))
1520 tile |= DF_HIGHLIGHT; /* completion flash */
1521
1522 error = ds->errtmp[y*w+x];
1523
1524 if (ds->tiles[y*w+x] != tile ||
1525 ds->pencil[y*w+x] != pencil ||
1526 ds->errors[y*w+x] != error) {
1527 ds->tiles[y*w+x] = tile;
1528 ds->pencil[y*w+x] = pencil;
1529 ds->errors[y*w+x] = error;
1530 draw_tile(dr, ds, x, y, tile, pencil, error);
1531 }
1532 }
1533 }
1534}
1535
1536static float game_anim_length(game_state *oldstate, game_state *newstate,
1537 int dir, game_ui *ui)
1538{
1539 return 0.0F;
1540}
1541
1542static float game_flash_length(game_state *oldstate, game_state *newstate,
1543 int dir, game_ui *ui)
1544{
1545 if (!oldstate->completed && newstate->completed &&
1546 !oldstate->cheated && !newstate->cheated)
1547 return FLASH_TIME;
1548 return 0.0F;
1549}
1550
1551static int game_timing_state(game_state *state, game_ui *ui)
1552{
1553 if (state->completed)
1554 return FALSE;
1555 return TRUE;
1556}
1557
1558static void game_print_size(game_params *params, float *x, float *y)
1559{
1560 int pw, ph;
1561
1562 /*
1563 * We use 9mm squares by default, like Solo.
1564 */
1565 game_compute_size(params, 900, &pw, &ph);
1566 *x = pw / 100.0F;
1567 *y = ph / 100.0F;
1568}
1569
1570static void game_print(drawing *dr, game_state *state, int tilesize)
1571{
1572 int w = state->par.w;
1573 int ink = print_mono_colour(dr, 0);
1574 int ehighlight = print_grey_colour(dr, 0.90F);
1575 int x, y;
1576
1577 /* Ick: fake up `ds->tilesize' for macro expansion purposes */
1578 game_drawstate ads, *ds = &ads;
1579 game_set_size(dr, ds, NULL, tilesize);
1580
1581 /*
1582 * Highlight the identity row and column.
1583 */
1584 for (x = 1; x < w; x++)
1585 draw_rect(dr, BORDER + x*TILESIZE, BORDER,
1586 TILESIZE, TILESIZE, ehighlight);
1587 for (y = 0; y < w; y++)
1588 draw_rect(dr, BORDER, BORDER + y*TILESIZE,
1589 TILESIZE, TILESIZE, ehighlight);
1590
1591 /*
1592 * Border.
1593 */
1594 print_line_width(dr, 3 * TILESIZE / 40);
1595 draw_rect_outline(dr, BORDER, BORDER, w*TILESIZE, w*TILESIZE, ink);
1596
1597 /*
1598 * Main grid.
1599 */
1600 for (x = 1; x < w; x++) {
1601 print_line_width(dr, TILESIZE / 40);
1602 draw_line(dr, BORDER+x*TILESIZE, BORDER,
1603 BORDER+x*TILESIZE, BORDER+w*TILESIZE, ink);
1604 }
1605 for (y = 1; y < w; y++) {
1606 print_line_width(dr, TILESIZE / 40);
1607 draw_line(dr, BORDER, BORDER+y*TILESIZE,
1608 BORDER+w*TILESIZE, BORDER+y*TILESIZE, ink);
1609 }
1610
1611 /*
1612 * Numbers.
1613 */
1614 for (y = 0; y < w; y++)
1615 for (x = 0; x < w; x++)
1616 if (state->grid[y*w+x]) {
1617 char str[2];
1618 str[1] = '\0';
1619 str[0] = TOCHAR(state->grid[y*w+x]);
1620 draw_text(dr, BORDER + x*TILESIZE + TILESIZE/2,
1621 BORDER + y*TILESIZE + TILESIZE/2,
1622 FONT_VARIABLE, TILESIZE/2,
1623 ALIGN_VCENTRE | ALIGN_HCENTRE, ink, str);
1624 }
1625}
1626
1627#ifdef COMBINED
1628#define thegame group
1629#endif
1630
1631const struct game thegame = {
1632 "Group", NULL, NULL,
1633 default_params,
1634 game_fetch_preset,
1635 decode_params,
1636 encode_params,
1637 free_params,
1638 dup_params,
1639 TRUE, game_configure, custom_params,
1640 validate_params,
1641 new_game_desc,
1642 validate_desc,
1643 new_game,
1644 dup_game,
1645 free_game,
1646 TRUE, solve_game,
1647 TRUE, game_can_format_as_text_now, game_text_format,
1648 new_ui,
1649 free_ui,
1650 encode_ui,
1651 decode_ui,
1652 game_changed_state,
1653 interpret_move,
1654 execute_move,
1655 PREFERRED_TILESIZE, game_compute_size, game_set_size,
1656 game_colours,
1657 game_new_drawstate,
1658 game_free_drawstate,
1659 game_redraw,
1660 game_anim_length,
1661 game_flash_length,
1662 TRUE, FALSE, game_print_size, game_print,
1663 FALSE, /* wants_statusbar */
1664 FALSE, game_timing_state,
1665 REQUIRE_RBUTTON | REQUIRE_NUMPAD, /* flags */
1666};
1667
1668#ifdef STANDALONE_SOLVER
1669
1670#include <stdarg.h>
1671
1672int main(int argc, char **argv)
1673{
1674 game_params *p;
1675 game_state *s;
1676 char *id = NULL, *desc, *err;
1677 digit *grid;
1678 int grade = FALSE;
1679 int ret, diff, really_show_working = FALSE;
1680
1681 while (--argc > 0) {
1682 char *p = *++argv;
1683 if (!strcmp(p, "-v")) {
1684 really_show_working = TRUE;
1685 } else if (!strcmp(p, "-g")) {
1686 grade = TRUE;
1687 } else if (*p == '-') {
1688 fprintf(stderr, "%s: unrecognised option `%s'\n", argv[0], p);
1689 return 1;
1690 } else {
1691 id = p;
1692 }
1693 }
1694
1695 if (!id) {
1696 fprintf(stderr, "usage: %s [-g | -v] <game_id>\n", argv[0]);
1697 return 1;
1698 }
1699
1700 desc = strchr(id, ':');
1701 if (!desc) {
1702 fprintf(stderr, "%s: game id expects a colon in it\n", argv[0]);
1703 return 1;
1704 }
1705 *desc++ = '\0';
1706
1707 p = default_params();
1708 decode_params(p, id);
1709 err = validate_desc(p, desc);
1710 if (err) {
1711 fprintf(stderr, "%s: %s\n", argv[0], err);
1712 return 1;
1713 }
1714 s = new_game(NULL, p, desc);
1715
1716 grid = snewn(p->w * p->w, digit);
1717
1718 /*
1719 * When solving a Normal puzzle, we don't want to bother the
1720 * user with Hard-level deductions. For this reason, we grade
1721 * the puzzle internally before doing anything else.
1722 */
1723 ret = -1; /* placate optimiser */
1724 solver_show_working = FALSE;
1725 for (diff = 0; diff < DIFFCOUNT; diff++) {
1726 memcpy(grid, s->grid, p->w * p->w);
1727 ret = solver(p->w, grid, diff);
1728 if (ret <= diff)
1729 break;
1730 }
1731
1732 if (diff == DIFFCOUNT) {
1733 if (grade)
1734 printf("Difficulty rating: ambiguous\n");
1735 else
1736 printf("Unable to find a unique solution\n");
1737 } else {
1738 if (grade) {
1739 if (ret == diff_impossible)
1740 printf("Difficulty rating: impossible (no solution exists)\n");
1741 else
1742 printf("Difficulty rating: %s\n", group_diffnames[ret]);
1743 } else {
1744 solver_show_working = really_show_working;
1745 memcpy(grid, s->grid, p->w * p->w);
1746 ret = solver(p->w, grid, diff);
1747 if (ret != diff)
1748 printf("Puzzle is inconsistent\n");
1749 else {
1750 memcpy(s->grid, grid, p->w * p->w);
1751 fputs(game_text_format(s), stdout);
1752 }
1753 }
1754 }
1755
1756 return 0;
1757}
1758
1759#endif
1760
1761/* vim: set shiftwidth=4 tabstop=8: */
Simon Tatham's portable puzzles collection; import of svn://svn.tartarus.org/sgt/puzzles