32ee875d |
1 | /* |
2 | * pegs.c: the classic Peg Solitaire game. |
3 | */ |
4 | |
5 | #include <stdio.h> |
6 | #include <stdlib.h> |
7 | #include <string.h> |
8 | #include <assert.h> |
9 | #include <ctype.h> |
10 | #include <math.h> |
11 | |
12 | #include "puzzles.h" |
13 | #include "tree234.h" |
14 | |
15 | #define GRID_HOLE 0 |
16 | #define GRID_PEG 1 |
17 | #define GRID_OBST 2 |
18 | |
19 | enum { |
20 | COL_BACKGROUND, |
21 | COL_HIGHLIGHT, |
22 | COL_LOWLIGHT, |
23 | COL_PEG, |
24 | NCOLOURS |
25 | }; |
26 | |
27 | /* |
28 | * Grid shapes. I do some macro ickery here to ensure that my enum |
29 | * and the various forms of my name list always match up. |
30 | */ |
31 | #define TYPELIST(A) \ |
32 | A(CROSS,Cross,cross) \ |
33 | A(OCTAGON,Octagon,octagon) \ |
34 | A(RANDOM,Random,random) |
35 | #define ENUM(upper,title,lower) TYPE_ ## upper, |
36 | #define TITLE(upper,title,lower) #title, |
37 | #define LOWER(upper,title,lower) #lower, |
38 | #define CONFIG(upper,title,lower) ":" #title |
39 | |
40 | enum { TYPELIST(ENUM) TYPECOUNT }; |
41 | static char const *const pegs_titletypes[] = { TYPELIST(TITLE) }; |
42 | static char const *const pegs_lowertypes[] = { TYPELIST(LOWER) }; |
43 | #define TYPECONFIG TYPELIST(CONFIG) |
44 | |
a8c8847b |
45 | #define FLASH_FRAME 0.13F |
46 | |
32ee875d |
47 | struct game_params { |
48 | int w, h; |
49 | int type; |
50 | }; |
51 | |
52 | struct game_state { |
53 | int w, h; |
a8c8847b |
54 | int completed; |
32ee875d |
55 | unsigned char *grid; |
56 | }; |
57 | |
58 | static game_params *default_params(void) |
59 | { |
60 | game_params *ret = snew(game_params); |
61 | |
62 | ret->w = ret->h = 7; |
63 | ret->type = TYPE_CROSS; |
64 | |
65 | return ret; |
66 | } |
67 | |
68 | static const struct game_params pegs_presets[] = { |
69 | {7, 7, TYPE_CROSS}, |
70 | {7, 7, TYPE_OCTAGON}, |
71 | {5, 5, TYPE_RANDOM}, |
72 | {7, 7, TYPE_RANDOM}, |
73 | {9, 9, TYPE_RANDOM}, |
74 | }; |
75 | |
76 | static int game_fetch_preset(int i, char **name, game_params **params) |
77 | { |
78 | game_params *ret; |
79 | char str[80]; |
80 | |
81 | if (i < 0 || i >= lenof(pegs_presets)) |
82 | return FALSE; |
83 | |
84 | ret = snew(game_params); |
85 | *ret = pegs_presets[i]; |
86 | |
87 | strcpy(str, pegs_titletypes[ret->type]); |
88 | if (ret->type == TYPE_RANDOM) |
89 | sprintf(str + strlen(str), " %dx%d", ret->w, ret->h); |
90 | |
91 | *name = dupstr(str); |
92 | *params = ret; |
93 | return TRUE; |
94 | } |
95 | |
96 | static void free_params(game_params *params) |
97 | { |
98 | sfree(params); |
99 | } |
100 | |
101 | static game_params *dup_params(game_params *params) |
102 | { |
103 | game_params *ret = snew(game_params); |
104 | *ret = *params; /* structure copy */ |
105 | return ret; |
106 | } |
107 | |
108 | static void decode_params(game_params *params, char const *string) |
109 | { |
110 | char const *p = string; |
111 | int i; |
112 | |
113 | params->w = atoi(p); |
114 | while (*p && isdigit((unsigned char)*p)) p++; |
115 | if (*p == 'x') { |
116 | p++; |
117 | params->h = atoi(p); |
118 | while (*p && isdigit((unsigned char)*p)) p++; |
119 | } else { |
120 | params->h = params->w; |
121 | } |
122 | |
123 | for (i = 0; i < lenof(pegs_lowertypes); i++) |
124 | if (!strcmp(p, pegs_lowertypes[i])) |
125 | params->type = i; |
126 | } |
127 | |
128 | static char *encode_params(game_params *params, int full) |
129 | { |
130 | char str[80]; |
131 | |
132 | sprintf(str, "%dx%d", params->w, params->h); |
133 | if (full) { |
134 | assert(params->type >= 0 && params->type < lenof(pegs_lowertypes)); |
135 | strcat(str, pegs_lowertypes[params->type]); |
136 | } |
137 | return dupstr(str); |
138 | } |
139 | |
140 | static config_item *game_configure(game_params *params) |
141 | { |
142 | config_item *ret = snewn(4, config_item); |
143 | char buf[80]; |
144 | |
145 | ret[0].name = "Width"; |
146 | ret[0].type = C_STRING; |
147 | sprintf(buf, "%d", params->w); |
148 | ret[0].sval = dupstr(buf); |
149 | ret[0].ival = 0; |
150 | |
151 | ret[1].name = "Height"; |
152 | ret[1].type = C_STRING; |
153 | sprintf(buf, "%d", params->h); |
154 | ret[1].sval = dupstr(buf); |
155 | ret[1].ival = 0; |
156 | |
157 | ret[2].name = "Board type"; |
158 | ret[2].type = C_CHOICES; |
159 | ret[2].sval = TYPECONFIG; |
160 | ret[2].ival = params->type; |
161 | |
162 | ret[3].name = NULL; |
163 | ret[3].type = C_END; |
164 | ret[3].sval = NULL; |
165 | ret[3].ival = 0; |
166 | |
167 | return ret; |
168 | } |
169 | |
170 | static game_params *custom_params(config_item *cfg) |
171 | { |
172 | game_params *ret = snew(game_params); |
173 | |
174 | ret->w = atoi(cfg[0].sval); |
175 | ret->h = atoi(cfg[1].sval); |
176 | ret->type = cfg[2].ival; |
177 | |
178 | return ret; |
179 | } |
180 | |
3ff276f2 |
181 | static char *validate_params(game_params *params, int full) |
32ee875d |
182 | { |
3ff276f2 |
183 | if (full && (params->w <= 3 || params->h <= 3)) |
32ee875d |
184 | return "Width and height must both be greater than three"; |
185 | |
186 | /* |
187 | * It might be possible to implement generalisations of Cross |
188 | * and Octagon, but only if I can find a proof that they're all |
189 | * soluble. For the moment, therefore, I'm going to disallow |
190 | * them at any size other than the standard one. |
191 | */ |
3ff276f2 |
192 | if (full && (params->type == TYPE_CROSS || params->type == TYPE_OCTAGON)) { |
32ee875d |
193 | if (params->w != 7 || params->h != 7) |
194 | return "This board type is only supported at 7x7"; |
195 | } |
196 | return NULL; |
197 | } |
198 | |
199 | /* ---------------------------------------------------------------------- |
200 | * Beginning of code to generate random Peg Solitaire boards. |
201 | * |
202 | * This procedure is done with no aesthetic judgment, no effort at |
203 | * symmetry, no difficulty grading and generally no finesse |
204 | * whatsoever. We simply begin with an empty board containing a |
205 | * single peg, and repeatedly make random reverse moves until it's |
206 | * plausibly full. This typically yields a scrappy haphazard mess |
207 | * with several holes, an uneven shape, and no redeeming features |
208 | * except guaranteed solubility. |
209 | * |
210 | * My only concessions to sophistication are (a) to repeat the |
211 | * generation process until I at least get a grid that touches |
212 | * every edge of the specified board size, and (b) to try when |
213 | * selecting moves to reuse existing space rather than expanding |
214 | * into new space (so that non-rectangular board shape becomes a |
215 | * factor during play). |
216 | */ |
217 | |
218 | struct move { |
219 | /* |
220 | * x,y are the start point of the move during generation (hence |
221 | * its endpoint during normal play). |
222 | * |
223 | * dx,dy are the direction of the move during generation. |
224 | * Absolute value 1. Hence, for example, x=3,y=5,dx=1,dy=0 |
225 | * means that the move during generation starts at (3,5) and |
226 | * ends at (5,5), and vice versa during normal play. |
227 | */ |
228 | int x, y, dx, dy; |
229 | /* |
230 | * cost is 0, 1 or 2, depending on how many GRID_OBSTs we must |
231 | * turn into GRID_HOLEs to play this move. |
232 | */ |
233 | int cost; |
234 | }; |
235 | |
236 | static int movecmp(void *av, void *bv) |
237 | { |
238 | struct move *a = (struct move *)av; |
239 | struct move *b = (struct move *)bv; |
240 | |
241 | if (a->y < b->y) |
242 | return -1; |
243 | else if (a->y > b->y) |
244 | return +1; |
245 | |
246 | if (a->x < b->x) |
247 | return -1; |
248 | else if (a->x > b->x) |
249 | return +1; |
250 | |
251 | if (a->dy < b->dy) |
252 | return -1; |
253 | else if (a->dy > b->dy) |
254 | return +1; |
255 | |
256 | if (a->dx < b->dx) |
257 | return -1; |
258 | else if (a->dx > b->dx) |
259 | return +1; |
260 | |
261 | return 0; |
262 | } |
263 | |
264 | static int movecmpcost(void *av, void *bv) |
265 | { |
266 | struct move *a = (struct move *)av; |
267 | struct move *b = (struct move *)bv; |
268 | |
269 | if (a->cost < b->cost) |
270 | return -1; |
271 | else if (a->cost > b->cost) |
272 | return +1; |
273 | |
274 | return movecmp(av, bv); |
275 | } |
276 | |
277 | struct movetrees { |
278 | tree234 *bymove, *bycost; |
279 | }; |
280 | |
281 | static void update_moves(unsigned char *grid, int w, int h, int x, int y, |
282 | struct movetrees *trees) |
283 | { |
284 | struct move move; |
285 | int dir, pos; |
286 | |
287 | /* |
288 | * There are twelve moves that can include (x,y): three in each |
289 | * of four directions. Check each one to see if it's possible. |
290 | */ |
291 | for (dir = 0; dir < 4; dir++) { |
292 | int dx, dy; |
293 | |
294 | if (dir & 1) |
295 | dx = 0, dy = dir - 2; |
296 | else |
297 | dy = 0, dx = dir - 1; |
298 | |
299 | assert(abs(dx) + abs(dy) == 1); |
300 | |
301 | for (pos = 0; pos < 3; pos++) { |
302 | int v1, v2, v3; |
303 | |
304 | move.dx = dx; |
305 | move.dy = dy; |
306 | move.x = x - pos*dx; |
307 | move.y = y - pos*dy; |
308 | |
309 | if (move.x < 0 || move.x >= w || move.y < 0 || move.y >= h) |
310 | continue; /* completely invalid move */ |
311 | if (move.x+2*move.dx < 0 || move.x+2*move.dx >= w || |
312 | move.y+2*move.dy < 0 || move.y+2*move.dy >= h) |
313 | continue; /* completely invalid move */ |
314 | |
315 | v1 = grid[move.y * w + move.x]; |
316 | v2 = grid[(move.y+move.dy) * w + (move.x+move.dx)]; |
317 | v3 = grid[(move.y+2*move.dy)*w + (move.x+2*move.dx)]; |
318 | if (v1 == GRID_PEG && v2 != GRID_PEG && v3 != GRID_PEG) { |
319 | struct move *m; |
320 | |
321 | move.cost = (v2 == GRID_OBST) + (v3 == GRID_OBST); |
322 | |
323 | /* |
324 | * This move is possible. See if it's already in |
325 | * the tree. |
326 | */ |
327 | m = find234(trees->bymove, &move, NULL); |
328 | if (m && m->cost != move.cost) { |
329 | /* |
330 | * It's in the tree but listed with the wrong |
331 | * cost. Remove the old version. |
332 | */ |
333 | #ifdef GENERATION_DIAGNOSTICS |
334 | printf("correcting %d%+d,%d%+d at cost %d\n", |
335 | m->x, m->dx, m->y, m->dy, m->cost); |
336 | #endif |
337 | del234(trees->bymove, m); |
338 | del234(trees->bycost, m); |
339 | sfree(m); |
340 | m = NULL; |
341 | } |
342 | if (!m) { |
343 | struct move *m, *m2; |
344 | m = snew(struct move); |
345 | *m = move; |
346 | m2 = add234(trees->bymove, m); |
347 | m2 = add234(trees->bycost, m); |
348 | assert(m2 == m); |
349 | #ifdef GENERATION_DIAGNOSTICS |
350 | printf("adding %d%+d,%d%+d at cost %d\n", |
351 | move.x, move.dx, move.y, move.dy, move.cost); |
352 | #endif |
353 | } else { |
354 | #ifdef GENERATION_DIAGNOSTICS |
355 | printf("not adding %d%+d,%d%+d at cost %d\n", |
356 | move.x, move.dx, move.y, move.dy, move.cost); |
357 | #endif |
358 | } |
359 | } else { |
360 | /* |
361 | * This move is impossible. If it is already in the |
362 | * tree, delete it. |
363 | * |
364 | * (We make use here of the fact that del234 |
365 | * doesn't have to be passed a pointer to the |
366 | * _actual_ element it's deleting: it merely needs |
367 | * one that compares equal to it, and it will |
368 | * return the one it deletes.) |
369 | */ |
370 | struct move *m = del234(trees->bymove, &move); |
371 | #ifdef GENERATION_DIAGNOSTICS |
372 | printf("%sdeleting %d%+d,%d%+d\n", m ? "" : "not ", |
373 | move.x, move.dx, move.y, move.dy); |
374 | #endif |
375 | if (m) { |
376 | del234(trees->bycost, m); |
377 | sfree(m); |
378 | } |
379 | } |
380 | } |
381 | } |
382 | } |
383 | |
384 | static void pegs_genmoves(unsigned char *grid, int w, int h, random_state *rs) |
385 | { |
386 | struct movetrees atrees, *trees = &atrees; |
387 | struct move *m; |
388 | int x, y, i, nmoves; |
389 | |
390 | trees->bymove = newtree234(movecmp); |
391 | trees->bycost = newtree234(movecmpcost); |
392 | |
393 | for (y = 0; y < h; y++) |
394 | for (x = 0; x < w; x++) |
395 | if (grid[y*w+x] == GRID_PEG) |
396 | update_moves(grid, w, h, x, y, trees); |
397 | |
398 | nmoves = 0; |
399 | |
400 | while (1) { |
401 | int limit, maxcost, index; |
402 | struct move mtmp, move, *m; |
403 | |
404 | /* |
405 | * See how many moves we can make at zero cost. Make one, |
406 | * if possible. Failing that, make a one-cost move, and |
407 | * then a two-cost one. |
408 | * |
409 | * After filling at least half the input grid, we no longer |
410 | * accept cost-2 moves: if that's our only option, we give |
411 | * up and finish. |
412 | */ |
413 | mtmp.y = h+1; |
414 | maxcost = (nmoves < w*h/2 ? 2 : 1); |
415 | m = NULL; /* placate optimiser */ |
416 | for (mtmp.cost = 0; mtmp.cost <= maxcost; mtmp.cost++) { |
417 | limit = -1; |
418 | m = findrelpos234(trees->bycost, &mtmp, NULL, REL234_LT, &limit); |
419 | #ifdef GENERATION_DIAGNOSTICS |
420 | printf("%d moves available with cost %d\n", limit+1, mtmp.cost); |
421 | #endif |
422 | if (m) |
423 | break; |
424 | } |
425 | if (!m) |
426 | break; |
427 | |
428 | index = random_upto(rs, limit+1); |
429 | move = *(struct move *)index234(trees->bycost, index); |
430 | |
431 | #ifdef GENERATION_DIAGNOSTICS |
432 | printf("selecting move %d%+d,%d%+d at cost %d\n", |
433 | move.x, move.dx, move.y, move.dy, move.cost); |
434 | #endif |
435 | |
436 | grid[move.y * w + move.x] = GRID_HOLE; |
437 | grid[(move.y+move.dy) * w + (move.x+move.dx)] = GRID_PEG; |
438 | grid[(move.y+2*move.dy)*w + (move.x+2*move.dx)] = GRID_PEG; |
439 | |
440 | for (i = 0; i <= 2; i++) { |
441 | int tx = move.x + i*move.dx; |
442 | int ty = move.y + i*move.dy; |
443 | update_moves(grid, w, h, tx, ty, trees); |
444 | } |
445 | |
446 | nmoves++; |
447 | } |
448 | |
449 | while ((m = delpos234(trees->bymove, 0)) != NULL) { |
450 | del234(trees->bycost, m); |
451 | sfree(m); |
452 | } |
453 | freetree234(trees->bymove); |
454 | freetree234(trees->bycost); |
455 | } |
456 | |
457 | static void pegs_generate(unsigned char *grid, int w, int h, random_state *rs) |
458 | { |
459 | while (1) { |
460 | int x, y, extremes; |
461 | |
462 | memset(grid, GRID_OBST, w*h); |
463 | grid[(h/2) * w + (w/2)] = GRID_PEG; |
464 | #ifdef GENERATION_DIAGNOSTICS |
465 | printf("beginning move selection\n"); |
466 | #endif |
467 | pegs_genmoves(grid, w, h, rs); |
468 | #ifdef GENERATION_DIAGNOSTICS |
469 | printf("finished move selection\n"); |
470 | #endif |
471 | |
472 | extremes = 0; |
473 | for (y = 0; y < h; y++) { |
474 | if (grid[y*w+0] != GRID_OBST) |
475 | extremes |= 1; |
476 | if (grid[y*w+w-1] != GRID_OBST) |
477 | extremes |= 2; |
478 | } |
479 | for (x = 0; x < w; x++) { |
480 | if (grid[0*w+x] != GRID_OBST) |
481 | extremes |= 4; |
482 | if (grid[(h-1)*w+x] != GRID_OBST) |
483 | extremes |= 8; |
484 | } |
485 | |
486 | if (extremes == 15) |
487 | break; |
488 | #ifdef GENERATION_DIAGNOSTICS |
489 | printf("insufficient extent; trying again\n"); |
490 | #endif |
491 | } |
1b4fd2a2 |
492 | #ifdef GENERATION_DIAGNOSTICS |
32ee875d |
493 | fflush(stdout); |
1b4fd2a2 |
494 | #endif |
32ee875d |
495 | } |
496 | |
497 | /* ---------------------------------------------------------------------- |
498 | * End of board generation code. Now for the client code which uses |
499 | * it as part of the puzzle. |
500 | */ |
501 | |
502 | static char *new_game_desc(game_params *params, random_state *rs, |
503 | char **aux, int interactive) |
504 | { |
505 | int w = params->w, h = params->h; |
506 | unsigned char *grid; |
507 | char *ret; |
508 | int i; |
509 | |
510 | grid = snewn(w*h, unsigned char); |
511 | if (params->type == TYPE_RANDOM) { |
512 | pegs_generate(grid, w, h, rs); |
513 | } else { |
514 | int x, y, cx, cy, v; |
515 | |
516 | for (y = 0; y < h; y++) |
517 | for (x = 0; x < w; x++) { |
518 | v = GRID_OBST; /* placate optimiser */ |
519 | switch (params->type) { |
520 | case TYPE_CROSS: |
521 | cx = abs(x - w/2); |
522 | cy = abs(y - h/2); |
523 | if (cx == 0 && cy == 0) |
524 | v = GRID_HOLE; |
525 | else if (cx > 1 && cy > 1) |
526 | v = GRID_OBST; |
527 | else |
528 | v = GRID_PEG; |
529 | break; |
530 | case TYPE_OCTAGON: |
531 | cx = abs(x - w/2); |
532 | cy = abs(y - h/2); |
6dae1679 |
533 | if (cx + cy > 1 + max(w,h)/2) |
32ee875d |
534 | v = GRID_OBST; |
535 | else |
536 | v = GRID_PEG; |
537 | break; |
538 | } |
539 | grid[y*w+x] = v; |
540 | } |
6dae1679 |
541 | |
542 | if (params->type == TYPE_OCTAGON) { |
543 | /* |
544 | * The octagonal (European) solitaire layout is |
545 | * actually _insoluble_ with the starting hole at the |
546 | * centre. Here's a proof: |
547 | * |
548 | * Colour the squares of the board diagonally in |
549 | * stripes of three different colours, which I'll call |
550 | * A, B and C. So the board looks like this: |
551 | * |
552 | * A B C |
553 | * A B C A B |
554 | * A B C A B C A |
555 | * B C A B C A B |
556 | * C A B C A B C |
557 | * B C A B C |
558 | * A B C |
559 | * |
560 | * Suppose we keep running track of the number of pegs |
561 | * occuping each colour of square. This colouring has |
562 | * the property that any valid move whatsoever changes |
563 | * all three of those counts by one (two of them go |
564 | * down and one goes up), which means that the _parity_ |
565 | * of every count flips on every move. |
566 | * |
567 | * If the centre square starts off unoccupied, then |
568 | * there are twelve pegs on each colour and all three |
569 | * counts start off even; therefore, after 35 moves all |
570 | * three counts would have to be odd, which isn't |
571 | * possible if there's only one peg left. [] |
572 | * |
573 | * This proof works just as well if the starting hole |
574 | * is _any_ of the thirteen positions labelled B. Also, |
575 | * we can stripe the board in the opposite direction |
576 | * and rule out any square labelled B in that colouring |
577 | * as well. This leaves: |
578 | * |
579 | * Y n Y |
580 | * n n Y n n |
581 | * Y n n Y n n Y |
582 | * n Y Y n Y Y n |
583 | * Y n n Y n n Y |
584 | * n n Y n n |
585 | * Y n Y |
586 | * |
587 | * where the ns are squares we've proved insoluble, and |
588 | * the Ys are the ones remaining. |
589 | * |
590 | * That doesn't prove all those starting positions to |
591 | * be soluble, of course; they're merely the ones we |
592 | * _haven't_ proved to be impossible. Nevertheless, it |
593 | * turns out that they are all soluble, so when the |
594 | * user requests an Octagon board the simplest thing is |
595 | * to pick one of these at random. |
596 | * |
597 | * Rather than picking equiprobably from those twelve |
598 | * positions, we'll pick equiprobably from the three |
599 | * equivalence classes |
600 | */ |
601 | switch (random_upto(rs, 3)) { |
602 | case 0: |
603 | /* Remove a random corner piece. */ |
604 | { |
605 | int dx, dy; |
606 | |
607 | dx = random_upto(rs, 2) * 2 - 1; /* +1 or -1 */ |
608 | dy = random_upto(rs, 2) * 2 - 1; /* +1 or -1 */ |
609 | if (random_upto(rs, 2)) |
610 | dy *= 3; |
611 | else |
612 | dx *= 3; |
613 | grid[(3+dy)*w+(3+dx)] = GRID_HOLE; |
614 | } |
615 | break; |
616 | case 1: |
617 | /* Remove a random piece two from the centre. */ |
618 | { |
619 | int dx, dy; |
620 | dx = 2 * (random_upto(rs, 2) * 2 - 1); |
621 | if (random_upto(rs, 2)) |
622 | dy = 0; |
623 | else |
624 | dy = dx, dx = 0; |
625 | grid[(3+dy)*w+(3+dx)] = GRID_HOLE; |
626 | } |
627 | break; |
628 | default /* case 2 */: |
629 | /* Remove a random piece one from the centre. */ |
630 | { |
631 | int dx, dy; |
632 | dx = random_upto(rs, 2) * 2 - 1; |
633 | if (random_upto(rs, 2)) |
634 | dy = 0; |
635 | else |
636 | dy = dx, dx = 0; |
637 | grid[(3+dy)*w+(3+dx)] = GRID_HOLE; |
638 | } |
639 | break; |
640 | } |
641 | } |
32ee875d |
642 | } |
643 | |
644 | /* |
645 | * Encode a game description which is simply a long list of P |
646 | * for peg, H for hole or O for obstacle. |
647 | */ |
648 | ret = snewn(w*h+1, char); |
649 | for (i = 0; i < w*h; i++) |
650 | ret[i] = (grid[i] == GRID_PEG ? 'P' : |
651 | grid[i] == GRID_HOLE ? 'H' : 'O'); |
652 | ret[w*h] = '\0'; |
653 | |
654 | sfree(grid); |
655 | |
656 | return ret; |
657 | } |
658 | |
659 | static char *validate_desc(game_params *params, char *desc) |
660 | { |
661 | int len = params->w * params->h; |
662 | |
663 | if (len != strlen(desc)) |
664 | return "Game description is wrong length"; |
665 | if (len != strspn(desc, "PHO")) |
666 | return "Invalid character in game description"; |
667 | |
668 | return NULL; |
669 | } |
670 | |
671 | static game_state *new_game(midend_data *me, game_params *params, char *desc) |
672 | { |
673 | int w = params->w, h = params->h; |
674 | game_state *state = snew(game_state); |
675 | int i; |
676 | |
677 | state->w = w; |
678 | state->h = h; |
a8c8847b |
679 | state->completed = 0; |
32ee875d |
680 | state->grid = snewn(w*h, unsigned char); |
681 | for (i = 0; i < w*h; i++) |
682 | state->grid[i] = (desc[i] == 'P' ? GRID_PEG : |
683 | desc[i] == 'H' ? GRID_HOLE : GRID_OBST); |
684 | |
685 | return state; |
686 | } |
687 | |
688 | static game_state *dup_game(game_state *state) |
689 | { |
690 | int w = state->w, h = state->h; |
691 | game_state *ret = snew(game_state); |
692 | |
693 | ret->w = state->w; |
694 | ret->h = state->h; |
a8c8847b |
695 | ret->completed = state->completed; |
32ee875d |
696 | ret->grid = snewn(w*h, unsigned char); |
697 | memcpy(ret->grid, state->grid, w*h); |
698 | |
699 | return ret; |
700 | } |
701 | |
702 | static void free_game(game_state *state) |
703 | { |
704 | sfree(state->grid); |
705 | sfree(state); |
706 | } |
707 | |
708 | static char *solve_game(game_state *state, game_state *currstate, |
709 | char *aux, char **error) |
710 | { |
711 | return NULL; |
712 | } |
713 | |
714 | static char *game_text_format(game_state *state) |
715 | { |
716 | int w = state->w, h = state->h; |
717 | int x, y; |
718 | char *ret; |
719 | |
720 | ret = snewn((w+1)*h + 1, char); |
721 | |
722 | for (y = 0; y < h; y++) { |
723 | for (x = 0; x < w; x++) |
724 | ret[y*(w+1)+x] = (state->grid[y*w+x] == GRID_HOLE ? '-' : |
725 | state->grid[y*w+x] == GRID_PEG ? '*' : ' '); |
726 | ret[y*(w+1)+w] = '\n'; |
727 | } |
728 | ret[h*(w+1)] = '\0'; |
729 | |
730 | return ret; |
731 | } |
732 | |
733 | struct game_ui { |
734 | int dragging; /* boolean: is a drag in progress? */ |
735 | int sx, sy; /* grid coords of drag start cell */ |
736 | int dx, dy; /* pixel coords of current drag posn */ |
737 | }; |
738 | |
739 | static game_ui *new_ui(game_state *state) |
740 | { |
741 | game_ui *ui = snew(game_ui); |
742 | |
743 | ui->sx = ui->sy = ui->dx = ui->dy = 0; |
744 | ui->dragging = FALSE; |
745 | |
746 | return ui; |
747 | } |
748 | |
749 | static void free_ui(game_ui *ui) |
750 | { |
751 | sfree(ui); |
752 | } |
753 | |
754 | static char *encode_ui(game_ui *ui) |
755 | { |
756 | return NULL; |
757 | } |
758 | |
759 | static void decode_ui(game_ui *ui, char *encoding) |
760 | { |
761 | } |
762 | |
763 | static void game_changed_state(game_ui *ui, game_state *oldstate, |
764 | game_state *newstate) |
765 | { |
766 | /* |
767 | * Cancel a drag, in case the source square has become |
768 | * unoccupied. |
769 | */ |
770 | ui->dragging = FALSE; |
771 | } |
772 | |
773 | #define PREFERRED_TILE_SIZE 33 |
774 | #define TILESIZE (ds->tilesize) |
775 | #define BORDER (TILESIZE / 2) |
776 | |
777 | #define HIGHLIGHT_WIDTH (TILESIZE / 16) |
778 | |
779 | #define COORD(x) ( BORDER + (x) * TILESIZE ) |
780 | #define FROMCOORD(x) ( ((x) + TILESIZE - BORDER) / TILESIZE - 1 ) |
781 | |
782 | struct game_drawstate { |
783 | int tilesize; |
784 | blitter *drag_background; |
785 | int dragging, dragx, dragy; |
786 | int w, h; |
787 | unsigned char *grid; |
788 | int started; |
a8c8847b |
789 | int bgcolour; |
32ee875d |
790 | }; |
791 | |
792 | static char *interpret_move(game_state *state, game_ui *ui, game_drawstate *ds, |
793 | int x, int y, int button) |
794 | { |
795 | int w = state->w, h = state->h; |
796 | |
797 | if (button == LEFT_BUTTON) { |
798 | int tx, ty; |
799 | |
800 | /* |
801 | * Left button down: we attempt to start a drag. |
802 | */ |
803 | |
804 | /* |
805 | * There certainly shouldn't be a current drag in progress, |
806 | * unless the midend failed to send us button events in |
807 | * order; it has a responsibility to always get that right, |
808 | * so we can legitimately punish it by failing an |
809 | * assertion. |
810 | */ |
811 | assert(!ui->dragging); |
812 | |
813 | tx = FROMCOORD(x); |
814 | ty = FROMCOORD(y); |
815 | if (tx >= 0 && tx < w && ty >= 0 && ty < h && |
816 | state->grid[ty*w+tx] == GRID_PEG) { |
817 | ui->dragging = TRUE; |
818 | ui->sx = tx; |
819 | ui->sy = ty; |
820 | ui->dx = x; |
821 | ui->dy = y; |
822 | return ""; /* ui modified */ |
823 | } |
824 | } else if (button == LEFT_DRAG && ui->dragging) { |
825 | /* |
826 | * Mouse moved; just move the peg being dragged. |
827 | */ |
828 | ui->dx = x; |
829 | ui->dy = y; |
830 | return ""; /* ui modified */ |
831 | } else if (button == LEFT_RELEASE && ui->dragging) { |
832 | char buf[80]; |
833 | int tx, ty, dx, dy; |
834 | |
835 | /* |
836 | * Button released. Identify the target square of the drag, |
837 | * see if it represents a valid move, and if so make it. |
838 | */ |
839 | ui->dragging = FALSE; /* cancel the drag no matter what */ |
840 | tx = FROMCOORD(x); |
841 | ty = FROMCOORD(y); |
842 | if (tx < 0 || tx >= w || ty < 0 || ty >= h) |
843 | return ""; /* target out of range */ |
844 | dx = tx - ui->sx; |
845 | dy = ty - ui->sy; |
846 | if (max(abs(dx),abs(dy)) != 2 || min(abs(dx),abs(dy)) != 0) |
847 | return ""; /* move length was wrong */ |
848 | dx /= 2; |
849 | dy /= 2; |
850 | |
851 | if (state->grid[ty*w+tx] != GRID_HOLE || |
852 | state->grid[(ty-dy)*w+(tx-dx)] != GRID_PEG || |
853 | state->grid[ui->sy*w+ui->sx] != GRID_PEG) |
854 | return ""; /* grid contents were invalid */ |
855 | |
856 | /* |
857 | * We have a valid move. Encode it simply as source and |
858 | * destination coordinate pairs. |
859 | */ |
860 | sprintf(buf, "%d,%d-%d,%d", ui->sx, ui->sy, tx, ty); |
861 | return dupstr(buf); |
862 | } |
863 | return NULL; |
864 | } |
865 | |
866 | static game_state *execute_move(game_state *state, char *move) |
867 | { |
868 | int w = state->w, h = state->h; |
869 | int sx, sy, tx, ty; |
870 | game_state *ret; |
871 | |
00a32916 |
872 | if (sscanf(move, "%d,%d-%d,%d", &sx, &sy, &tx, &ty) == 4) { |
32ee875d |
873 | int mx, my, dx, dy; |
874 | |
875 | if (sx < 0 || sx >= w || sy < 0 || sy >= h) |
876 | return NULL; /* source out of range */ |
877 | if (tx < 0 || tx >= w || ty < 0 || ty >= h) |
878 | return NULL; /* target out of range */ |
879 | |
880 | dx = tx - sx; |
881 | dy = ty - sy; |
882 | if (max(abs(dx),abs(dy)) != 2 || min(abs(dx),abs(dy)) != 0) |
883 | return NULL; /* move length was wrong */ |
884 | mx = sx + dx/2; |
885 | my = sy + dy/2; |
886 | |
887 | if (state->grid[sy*w+sx] != GRID_PEG || |
888 | state->grid[my*w+mx] != GRID_PEG || |
889 | state->grid[ty*w+tx] != GRID_HOLE) |
890 | return NULL; /* grid contents were invalid */ |
891 | |
892 | ret = dup_game(state); |
893 | ret->grid[sy*w+sx] = GRID_HOLE; |
894 | ret->grid[my*w+mx] = GRID_HOLE; |
895 | ret->grid[ty*w+tx] = GRID_PEG; |
896 | |
a8c8847b |
897 | /* |
898 | * Opinion varies on whether getting to a single peg counts as |
899 | * completing the game, or whether that peg has to be at a |
900 | * specific location (central in the classic cross game, for |
901 | * instance). For now we take the former, rather lax position. |
902 | */ |
903 | if (!ret->completed) { |
904 | int count = 0, i; |
905 | for (i = 0; i < w*h; i++) |
906 | if (ret->grid[i] == GRID_PEG) |
907 | count++; |
908 | if (count == 1) |
909 | ret->completed = 1; |
910 | } |
911 | |
32ee875d |
912 | return ret; |
913 | } |
914 | return NULL; |
915 | } |
916 | |
917 | /* ---------------------------------------------------------------------- |
918 | * Drawing routines. |
919 | */ |
920 | |
1f3ee4ee |
921 | static void game_compute_size(game_params *params, int tilesize, |
922 | int *x, int *y) |
32ee875d |
923 | { |
1f3ee4ee |
924 | /* Ick: fake up `ds->tilesize' for macro expansion purposes */ |
925 | struct { int tilesize; } ads, *ds = &ads; |
926 | ads.tilesize = tilesize; |
32ee875d |
927 | |
928 | *x = TILESIZE * params->w + 2 * BORDER; |
929 | *y = TILESIZE * params->h + 2 * BORDER; |
1f3ee4ee |
930 | } |
931 | |
932 | static void game_set_size(game_drawstate *ds, game_params *params, |
933 | int tilesize) |
934 | { |
935 | ds->tilesize = tilesize; |
936 | |
937 | assert(TILESIZE > 0); |
32ee875d |
938 | |
939 | if (ds->drag_background) |
940 | blitter_free(ds->drag_background); |
941 | ds->drag_background = blitter_new(TILESIZE, TILESIZE); |
942 | } |
943 | |
944 | static float *game_colours(frontend *fe, game_state *state, int *ncolours) |
945 | { |
946 | float *ret = snewn(3 * NCOLOURS, float); |
32ee875d |
947 | |
937a9eff |
948 | game_mkhighlight(fe, ret, COL_BACKGROUND, COL_HIGHLIGHT, COL_LOWLIGHT); |
32ee875d |
949 | |
950 | ret[COL_PEG * 3 + 0] = 0.0F; |
951 | ret[COL_PEG * 3 + 1] = 0.0F; |
952 | ret[COL_PEG * 3 + 2] = 1.0F; |
953 | |
954 | *ncolours = NCOLOURS; |
955 | return ret; |
956 | } |
957 | |
958 | static game_drawstate *game_new_drawstate(game_state *state) |
959 | { |
960 | int w = state->w, h = state->h; |
961 | struct game_drawstate *ds = snew(struct game_drawstate); |
962 | |
963 | ds->tilesize = 0; /* not decided yet */ |
964 | |
965 | /* We can't allocate the blitter rectangle for the drag background |
966 | * until we know what size to make it. */ |
967 | ds->drag_background = NULL; |
968 | ds->dragging = FALSE; |
969 | |
970 | ds->w = w; |
971 | ds->h = h; |
972 | ds->grid = snewn(w*h, unsigned char); |
973 | memset(ds->grid, 255, w*h); |
974 | |
975 | ds->started = FALSE; |
a8c8847b |
976 | ds->bgcolour = -1; |
32ee875d |
977 | |
978 | return ds; |
979 | } |
980 | |
981 | static void game_free_drawstate(game_drawstate *ds) |
982 | { |
983 | if (ds->drag_background) |
984 | blitter_free(ds->drag_background); |
985 | sfree(ds->grid); |
986 | sfree(ds); |
987 | } |
988 | |
989 | static void draw_tile(frontend *fe, game_drawstate *ds, |
a8c8847b |
990 | int x, int y, int v, int bgcolour) |
32ee875d |
991 | { |
a8c8847b |
992 | if (bgcolour >= 0) { |
993 | draw_rect(fe, x, y, TILESIZE, TILESIZE, bgcolour); |
32ee875d |
994 | } |
995 | |
996 | if (v == GRID_HOLE) { |
997 | draw_circle(fe, x+TILESIZE/2, y+TILESIZE/2, TILESIZE/4, |
998 | COL_LOWLIGHT, COL_LOWLIGHT); |
999 | } else if (v == GRID_PEG) { |
1000 | draw_circle(fe, x+TILESIZE/2, y+TILESIZE/2, TILESIZE/3, |
1001 | COL_PEG, COL_PEG); |
1002 | } |
1003 | |
1004 | draw_update(fe, x, y, TILESIZE, TILESIZE); |
1005 | } |
1006 | |
1007 | static void game_redraw(frontend *fe, game_drawstate *ds, game_state *oldstate, |
1008 | game_state *state, int dir, game_ui *ui, |
1009 | float animtime, float flashtime) |
1010 | { |
1011 | int w = state->w, h = state->h; |
1012 | int x, y; |
a8c8847b |
1013 | int bgcolour; |
1014 | |
1015 | if (flashtime > 0) { |
1016 | int frame = (int)(flashtime / FLASH_FRAME); |
1017 | bgcolour = (frame % 2 ? COL_LOWLIGHT : COL_HIGHLIGHT); |
1018 | } else |
1019 | bgcolour = COL_BACKGROUND; |
32ee875d |
1020 | |
1021 | /* |
1022 | * Erase the sprite currently being dragged, if any. |
1023 | */ |
1024 | if (ds->dragging) { |
1025 | assert(ds->drag_background); |
1026 | blitter_load(fe, ds->drag_background, ds->dragx, ds->dragy); |
1027 | draw_update(fe, ds->dragx, ds->dragy, TILESIZE, TILESIZE); |
1028 | ds->dragging = FALSE; |
1029 | } |
1030 | |
1031 | if (!ds->started) { |
1032 | draw_rect(fe, 0, 0, |
1033 | TILESIZE * state->w + 2 * BORDER, |
1034 | TILESIZE * state->h + 2 * BORDER, COL_BACKGROUND); |
1035 | |
1036 | /* |
1037 | * Draw relief marks around all the squares that aren't |
1038 | * GRID_OBST. |
1039 | */ |
1040 | for (y = 0; y < h; y++) |
1041 | for (x = 0; x < w; x++) |
1042 | if (state->grid[y*w+x] != GRID_OBST) { |
1043 | /* |
1044 | * First pass: draw the full relief square. |
1045 | */ |
1046 | int coords[6]; |
1047 | coords[0] = COORD(x+1) + HIGHLIGHT_WIDTH - 1; |
1048 | coords[1] = COORD(y) - HIGHLIGHT_WIDTH; |
1049 | coords[2] = COORD(x) - HIGHLIGHT_WIDTH; |
1050 | coords[3] = COORD(y+1) + HIGHLIGHT_WIDTH - 1; |
1051 | coords[4] = COORD(x) - HIGHLIGHT_WIDTH; |
1052 | coords[5] = COORD(y) - HIGHLIGHT_WIDTH; |
1053 | draw_polygon(fe, coords, 3, COL_HIGHLIGHT, COL_HIGHLIGHT); |
1054 | coords[4] = COORD(x+1) + HIGHLIGHT_WIDTH - 1; |
1055 | coords[5] = COORD(y+1) + HIGHLIGHT_WIDTH - 1; |
1056 | draw_polygon(fe, coords, 3, COL_LOWLIGHT, COL_LOWLIGHT); |
1057 | } |
1058 | for (y = 0; y < h; y++) |
1059 | for (x = 0; x < w; x++) |
1060 | if (state->grid[y*w+x] != GRID_OBST) { |
1061 | /* |
1062 | * Second pass: draw everything but the two |
1063 | * diagonal corners. |
1064 | */ |
1065 | draw_rect(fe, COORD(x) - HIGHLIGHT_WIDTH, |
1066 | COORD(y) - HIGHLIGHT_WIDTH, |
1067 | TILESIZE + HIGHLIGHT_WIDTH, |
1068 | TILESIZE + HIGHLIGHT_WIDTH, COL_HIGHLIGHT); |
1069 | draw_rect(fe, COORD(x), |
1070 | COORD(y), |
1071 | TILESIZE + HIGHLIGHT_WIDTH, |
1072 | TILESIZE + HIGHLIGHT_WIDTH, COL_LOWLIGHT); |
1073 | } |
1074 | for (y = 0; y < h; y++) |
1075 | for (x = 0; x < w; x++) |
1076 | if (state->grid[y*w+x] != GRID_OBST) { |
1077 | /* |
1078 | * Third pass: draw a trapezium on each edge. |
1079 | */ |
1080 | int coords[8]; |
1081 | int dx, dy, s, sn, c; |
1082 | |
1083 | for (dx = 0; dx < 2; dx++) { |
1084 | dy = 1 - dx; |
1085 | for (s = 0; s < 2; s++) { |
1086 | sn = 2*s - 1; |
1087 | c = s ? COL_LOWLIGHT : COL_HIGHLIGHT; |
1088 | |
1089 | coords[0] = COORD(x) + (s*dx)*(TILESIZE-1); |
1090 | coords[1] = COORD(y) + (s*dy)*(TILESIZE-1); |
1091 | coords[2] = COORD(x) + (s*dx+dy)*(TILESIZE-1); |
1092 | coords[3] = COORD(y) + (s*dy+dx)*(TILESIZE-1); |
1093 | coords[4] = coords[2] - HIGHLIGHT_WIDTH * (dy-sn*dx); |
1094 | coords[5] = coords[3] - HIGHLIGHT_WIDTH * (dx-sn*dy); |
1095 | coords[6] = coords[0] + HIGHLIGHT_WIDTH * (dy+sn*dx); |
1096 | coords[7] = coords[1] + HIGHLIGHT_WIDTH * (dx+sn*dy); |
1097 | draw_polygon(fe, coords, 4, c, c); |
1098 | } |
1099 | } |
1100 | } |
1101 | for (y = 0; y < h; y++) |
1102 | for (x = 0; x < w; x++) |
1103 | if (state->grid[y*w+x] != GRID_OBST) { |
1104 | /* |
1105 | * Second pass: draw everything but the two |
1106 | * diagonal corners. |
1107 | */ |
1108 | draw_rect(fe, COORD(x), |
1109 | COORD(y), |
1110 | TILESIZE, |
1111 | TILESIZE, COL_BACKGROUND); |
1112 | } |
1113 | |
1114 | ds->started = TRUE; |
1115 | |
1116 | draw_update(fe, 0, 0, |
1117 | TILESIZE * state->w + 2 * BORDER, |
1118 | TILESIZE * state->h + 2 * BORDER); |
1119 | } |
1120 | |
1121 | /* |
1122 | * Loop over the grid redrawing anything that looks as if it |
1123 | * needs it. |
1124 | */ |
1125 | for (y = 0; y < h; y++) |
1126 | for (x = 0; x < w; x++) { |
1127 | int v; |
1128 | |
1129 | v = state->grid[y*w+x]; |
1130 | /* |
1131 | * Blank the source of a drag so it looks as if the |
1132 | * user picked the peg up physically. |
1133 | */ |
1134 | if (ui->dragging && ui->sx == x && ui->sy == y && v == GRID_PEG) |
1135 | v = GRID_HOLE; |
a8c8847b |
1136 | if (v != GRID_OBST && |
1137 | (bgcolour != ds->bgcolour || /* always redraw when flashing */ |
1138 | v != ds->grid[y*w+x])) { |
1139 | draw_tile(fe, ds, COORD(x), COORD(y), v, bgcolour); |
32ee875d |
1140 | } |
1141 | } |
1142 | |
1143 | /* |
1144 | * Draw the dragging sprite if any. |
1145 | */ |
1146 | if (ui->dragging) { |
1147 | ds->dragging = TRUE; |
1148 | ds->dragx = ui->dx - TILESIZE/2; |
1149 | ds->dragy = ui->dy - TILESIZE/2; |
1150 | blitter_save(fe, ds->drag_background, ds->dragx, ds->dragy); |
a8c8847b |
1151 | draw_tile(fe, ds, ds->dragx, ds->dragy, GRID_PEG, -1); |
32ee875d |
1152 | } |
a8c8847b |
1153 | |
1154 | ds->bgcolour = bgcolour; |
32ee875d |
1155 | } |
1156 | |
1157 | static float game_anim_length(game_state *oldstate, game_state *newstate, |
1158 | int dir, game_ui *ui) |
1159 | { |
1160 | return 0.0F; |
1161 | } |
1162 | |
1163 | static float game_flash_length(game_state *oldstate, game_state *newstate, |
1164 | int dir, game_ui *ui) |
1165 | { |
a8c8847b |
1166 | if (!oldstate->completed && newstate->completed) |
1167 | return 2 * FLASH_FRAME; |
1168 | else |
1169 | return 0.0F; |
32ee875d |
1170 | } |
1171 | |
1172 | static int game_wants_statusbar(void) |
1173 | { |
1174 | return FALSE; |
1175 | } |
1176 | |
4d08de49 |
1177 | static int game_timing_state(game_state *state, game_ui *ui) |
32ee875d |
1178 | { |
1179 | return TRUE; |
1180 | } |
1181 | |
1182 | #ifdef COMBINED |
1183 | #define thegame pegs |
1184 | #endif |
1185 | |
1186 | const struct game thegame = { |
11aeddcc |
1187 | "Pegs", "games.pegs", |
32ee875d |
1188 | default_params, |
1189 | game_fetch_preset, |
1190 | decode_params, |
1191 | encode_params, |
1192 | free_params, |
1193 | dup_params, |
1194 | TRUE, game_configure, custom_params, |
1195 | validate_params, |
1196 | new_game_desc, |
1197 | validate_desc, |
1198 | new_game, |
1199 | dup_game, |
1200 | free_game, |
1201 | FALSE, solve_game, |
1202 | TRUE, game_text_format, |
1203 | new_ui, |
1204 | free_ui, |
1205 | encode_ui, |
1206 | decode_ui, |
1207 | game_changed_state, |
1208 | interpret_move, |
1209 | execute_move, |
1f3ee4ee |
1210 | PREFERRED_TILE_SIZE, game_compute_size, game_set_size, |
32ee875d |
1211 | game_colours, |
1212 | game_new_drawstate, |
1213 | game_free_drawstate, |
1214 | game_redraw, |
1215 | game_anim_length, |
1216 | game_flash_length, |
1217 | game_wants_statusbar, |
1218 | FALSE, game_timing_state, |
1219 | 0, /* mouse_priorities */ |
1220 | }; |