2 * loopy.c: An implementation of the Nikoli game 'Loop the loop'.
5 * vim: set shiftwidth=4 :set textwidth=80:
11 * - setting very high recursion depth seems to cause memory
12 * munching: are we recursing before checking completion, by any
15 * - there's an interesting deductive technique which makes use of
16 * topology rather than just graph theory. Each _square_ in the
17 * grid is either inside or outside the loop; you can tell that
18 * two squares are on the same side of the loop if they're
19 * separated by an x (or, more generally, by a path crossing no
20 * LINE_UNKNOWNs and an even number of LINE_YESes), and on the
21 * opposite side of the loop if they're separated by a line (or
22 * an odd number of LINE_YESes and no LINE_UNKNOWNs). Oh, and
23 * any square separated from the outside of the grid by a
24 * LINE_YES or a LINE_NO is on the inside or outside
25 * respectively. So if you can track this for all squares, you
26 * can occasionally spot that two squares are separated by a
27 * LINE_UNKNOWN but their relative insideness is known, and
28 * therefore deduce the state of the edge between them.
29 * + An efficient way to track this would be by augmenting the
30 * disjoint set forest data structure. Each element, along
31 * with a pointer to a parent member of its equivalence
32 * class, would also carry a one-bit field indicating whether
33 * it was equal or opposite to its parent. Then you could
34 * keep flipping a bit as you ascended the tree during
35 * dsf_canonify(), and hence you'd be able to return the
36 * relationship of the input value to its ultimate parent
37 * (and also you could then get all those bits right when you
38 * went back up the tree rewriting). So you'd be able to
39 * query whether any two elements were known-equal,
40 * known-opposite, or not-known, and you could add new
41 * equalities or oppositenesses to increase your knowledge.
42 * (Of course the algorithm would have to fail an assertion
43 * if you tried to tell it two things it already knew to be
44 * opposite were equal, or vice versa!)
57 #define PREFERRED_TILE_SIZE 32
58 #define TILE_SIZE (ds->tilesize)
59 #define LINEWIDTH TILE_SIZE / 16
60 #define BORDER (TILE_SIZE / 2)
62 #define FLASH_TIME 0.4F
64 #define HL_COUNT(state) ((state)->w * ((state)->h + 1))
65 #define VL_COUNT(state) (((state)->w + 1) * (state)->h)
66 #define DOT_COUNT(state) (((state)->w + 1) * ((state)->h + 1))
67 #define SQUARE_COUNT(state) ((state)->w * (state)->h)
69 #define ABOVE_SQUARE(state, i, j) ((state)->hl[(i) + (state)->w * (j)])
70 #define BELOW_SQUARE(state, i, j) ABOVE_SQUARE(state, i, (j)+1)
72 #define LEFTOF_SQUARE(state, i, j) ((state)->vl[(i) + ((state)->w + 1) * (j)])
73 #define RIGHTOF_SQUARE(state, i, j) LEFTOF_SQUARE(state, (i)+1, j)
75 #define LEGAL_DOT(state, i, j) ((i) >= 0 && (j) >= 0 && \
76 (i) <= (state)->w && (j) <= (state)->h)
79 * These macros return rvalues only, but can cope with being passed
80 * out-of-range coordinates.
82 #define ABOVE_DOT(state, i, j) ((!LEGAL_DOT(state, i, j) || j <= 0) ? \
83 LINE_NO : LV_ABOVE_DOT(state, i, j))
84 #define BELOW_DOT(state, i, j) ((!LEGAL_DOT(state, i, j) || j >= (state)->h) ? \
85 LINE_NO : LV_BELOW_DOT(state, i, j))
87 #define LEFTOF_DOT(state, i, j) ((!LEGAL_DOT(state, i, j) || i <= 0) ? \
88 LINE_NO : LV_LEFTOF_DOT(state, i, j))
89 #define RIGHTOF_DOT(state, i, j) ((!LEGAL_DOT(state, i, j) || i >= (state)->w)?\
90 LINE_NO : LV_RIGHTOF_DOT(state, i, j))
93 * These macros expect to be passed valid coordinates, and return
96 #define LV_BELOW_DOT(state, i, j) ((state)->vl[(i) + ((state)->w + 1) * (j)])
97 #define LV_ABOVE_DOT(state, i, j) LV_BELOW_DOT(state, i, (j)-1)
99 #define LV_RIGHTOF_DOT(state, i, j) ((state)->hl[(i) + (state)->w * (j)])
100 #define LV_LEFTOF_DOT(state, i, j) LV_RIGHTOF_DOT(state, (i)-1, j)
102 #define CLUE_AT(state, i, j) ((i < 0 || i >= (state)->w || \
103 j < 0 || j >= (state)->h) ? \
104 ' ' : LV_CLUE_AT(state, i, j))
106 #define LV_CLUE_AT(state, i, j) ((state)->clues[(i) + (state)->w * (j)])
108 #define OPP(dir) (dir == LINE_UNKNOWN ? LINE_UNKNOWN : \
109 dir == LINE_YES ? LINE_NO : LINE_YES)
111 static char *game_text_format(game_state *state);
120 enum line_state { LINE_UNKNOWN, LINE_YES, LINE_NO };
122 enum direction { UP, DOWN, LEFT, RIGHT };
131 /* Put ' ' in a square that doesn't get a clue */
134 /* Arrays of line states, stored left-to-right, top-to-bottom */
143 static game_state *dup_game(game_state *state)
145 game_state *ret = snew(game_state);
149 ret->solved = state->solved;
150 ret->cheated = state->cheated;
152 ret->clues = snewn(SQUARE_COUNT(state), char);
153 memcpy(ret->clues, state->clues, SQUARE_COUNT(state));
155 ret->hl = snewn(HL_COUNT(state), char);
156 memcpy(ret->hl, state->hl, HL_COUNT(state));
158 ret->vl = snewn(VL_COUNT(state), char);
159 memcpy(ret->vl, state->vl, VL_COUNT(state));
161 ret->recursion_depth = state->recursion_depth;
166 static void free_game(game_state *state)
177 SOLVER_SOLVED, /* This is the only solution the solver could find */
178 SOLVER_MISTAKE, /* This is definitely not a solution */
179 SOLVER_AMBIGUOUS, /* This _might_ be an ambiguous solution */
180 SOLVER_INCOMPLETE /* This may be a partial solution */
183 typedef struct solver_state {
185 /* XXX dot_atleastone[i,j, dline] is equivalent to */
186 /* dot_atmostone[i,j,OPP_DLINE(dline)] */
187 char *dot_atleastone;
189 /* char *dline_identical; */
190 int recursion_remaining;
191 enum solver_status solver_status;
192 int *dotdsf, *looplen;
195 static solver_state *new_solver_state(game_state *state) {
196 solver_state *ret = snew(solver_state);
199 ret->state = dup_game(state);
201 ret->dot_atmostone = snewn(DOT_COUNT(state), char);
202 memset(ret->dot_atmostone, 0, DOT_COUNT(state));
203 ret->dot_atleastone = snewn(DOT_COUNT(state), char);
204 memset(ret->dot_atleastone, 0, DOT_COUNT(state));
207 dline_identical = snewn(DOT_COUNT(state), char);
208 memset(dline_identical, 0, DOT_COUNT(state));
211 ret->recursion_remaining = state->recursion_depth;
212 ret->solver_status = SOLVER_INCOMPLETE; /* XXX This may be a lie */
214 ret->dotdsf = snewn(DOT_COUNT(state), int);
215 ret->looplen = snewn(DOT_COUNT(state), int);
216 for (i = 0; i < DOT_COUNT(state); i++) {
224 static void free_solver_state(solver_state *sstate) {
226 free_game(sstate->state);
227 sfree(sstate->dot_atleastone);
228 sfree(sstate->dot_atmostone);
229 /* sfree(sstate->dline_identical); */
230 sfree(sstate->dotdsf);
231 sfree(sstate->looplen);
236 static solver_state *dup_solver_state(solver_state *sstate) {
239 solver_state *ret = snew(solver_state);
241 ret->state = state = dup_game(sstate->state);
243 ret->dot_atmostone = snewn(DOT_COUNT(state), char);
244 memcpy(ret->dot_atmostone, sstate->dot_atmostone, DOT_COUNT(state));
246 ret->dot_atleastone = snewn(DOT_COUNT(state), char);
247 memcpy(ret->dot_atleastone, sstate->dot_atleastone, DOT_COUNT(state));
250 ret->dline_identical = snewn((state->w + 1) * (state->h + 1), char);
251 memcpy(ret->dline_identical, state->dot_atmostone,
252 (state->w + 1) * (state->h + 1));
255 ret->recursion_remaining = sstate->recursion_remaining;
256 ret->solver_status = sstate->solver_status;
258 ret->dotdsf = snewn(DOT_COUNT(state), int);
259 ret->looplen = snewn(DOT_COUNT(state), int);
260 memcpy(ret->dotdsf, sstate->dotdsf, DOT_COUNT(state) * sizeof(int));
261 memcpy(ret->looplen, sstate->looplen, DOT_COUNT(state) * sizeof(int));
267 * Merge two dots due to the existence of an edge between them.
268 * Updates the dsf tracking equivalence classes, and keeps track of
269 * the length of path each dot is currently a part of.
271 static void merge_dots(solver_state *sstate, int x1, int y1, int x2, int y2)
275 i = y1 * (sstate->state->w + 1) + x1;
276 j = y2 * (sstate->state->w + 1) + x2;
278 i = dsf_canonify(sstate->dotdsf, i);
279 j = dsf_canonify(sstate->dotdsf, j);
282 len = sstate->looplen[i] + sstate->looplen[j];
283 dsf_merge(sstate->dotdsf, i, j);
284 i = dsf_canonify(sstate->dotdsf, i);
285 sstate->looplen[i] = len;
289 /* Count the number of lines of a particular type currently going into the
290 * given dot. Lines going off the edge of the board are assumed fixed no. */
291 static int dot_order(const game_state* state, int i, int j, char line_type)
296 if (LEFTOF_DOT(state, i, j) == line_type)
299 if (line_type == LINE_NO)
303 if (RIGHTOF_DOT(state, i, j) == line_type)
306 if (line_type == LINE_NO)
310 if (ABOVE_DOT(state, i, j) == line_type)
313 if (line_type == LINE_NO)
317 if (BELOW_DOT(state, i, j) == line_type)
320 if (line_type == LINE_NO)
326 /* Count the number of lines of a particular type currently surrounding the
328 static int square_order(const game_state* state, int i, int j, char line_type)
332 if (ABOVE_SQUARE(state, i, j) == line_type)
334 if (BELOW_SQUARE(state, i, j) == line_type)
336 if (LEFTOF_SQUARE(state, i, j) == line_type)
338 if (RIGHTOF_SQUARE(state, i, j) == line_type)
344 /* Set all lines bordering a dot of type old_type to type new_type */
345 static void dot_setall(game_state *state, int i, int j,
346 char old_type, char new_type)
348 /* printf("dot_setall([%d,%d], %d, %d)\n", i, j, old_type, new_type); */
349 if (i > 0 && LEFTOF_DOT(state, i, j) == old_type)
350 LV_LEFTOF_DOT(state, i, j) = new_type;
351 if (i < state->w && RIGHTOF_DOT(state, i, j) == old_type)
352 LV_RIGHTOF_DOT(state, i, j) = new_type;
353 if (j > 0 && ABOVE_DOT(state, i, j) == old_type)
354 LV_ABOVE_DOT(state, i, j) = new_type;
355 if (j < state->h && BELOW_DOT(state, i, j) == old_type)
356 LV_BELOW_DOT(state, i, j) = new_type;
358 /* Set all lines bordering a square of type old_type to type new_type */
359 static void square_setall(game_state *state, int i, int j,
360 char old_type, char new_type)
362 if (ABOVE_SQUARE(state, i, j) == old_type)
363 ABOVE_SQUARE(state, i, j) = new_type;
364 if (BELOW_SQUARE(state, i, j) == old_type)
365 BELOW_SQUARE(state, i, j) = new_type;
366 if (LEFTOF_SQUARE(state, i, j) == old_type)
367 LEFTOF_SQUARE(state, i, j) = new_type;
368 if (RIGHTOF_SQUARE(state, i, j) == old_type)
369 RIGHTOF_SQUARE(state, i, j) = new_type;
372 static game_params *default_params(void)
374 game_params *ret = snew(game_params);
383 static game_params *dup_params(game_params *params)
385 game_params *ret = snew(game_params);
386 *ret = *params; /* structure copy */
390 static const struct {
393 } loopy_presets[] = {
394 { "4x4 Easy", { 4, 4, 0 } },
395 { "4x4 Hard", { 4, 4, 2 } },
396 { "7x7 Easy", { 7, 7, 0 } },
397 { "7x7 Hard", { 7, 7, 2 } },
398 { "10x10 Easy", { 10, 10, 0 } },
399 { "10x10 Hard", { 10, 10, 2 } },
400 { "15x15 Easy", { 15, 15, 0 } },
401 { "30x20 Easy", { 30, 20, 0 } }
404 static int game_fetch_preset(int i, char **name, game_params **params)
408 if (i < 0 || i >= lenof(loopy_presets))
411 tmppar = loopy_presets[i].params;
412 *params = dup_params(&tmppar);
413 *name = dupstr(loopy_presets[i].desc);
418 static void free_params(game_params *params)
423 static void decode_params(game_params *params, char const *string)
425 params->h = params->w = atoi(string);
427 while (*string && isdigit((unsigned char)*string)) string++;
428 if (*string == 'x') {
430 params->h = atoi(string);
431 while (*string && isdigit((unsigned char)*string)) string++;
433 if (*string == 'r') {
435 params->rec = atoi(string);
436 while (*string && isdigit((unsigned char)*string)) string++;
440 static char *encode_params(game_params *params, int full)
443 sprintf(str, "%dx%d", params->w, params->h);
445 sprintf(str + strlen(str), "r%d", params->rec);
449 static config_item *game_configure(game_params *params)
454 ret = snewn(4, config_item);
456 ret[0].name = "Width";
457 ret[0].type = C_STRING;
458 sprintf(buf, "%d", params->w);
459 ret[0].sval = dupstr(buf);
462 ret[1].name = "Height";
463 ret[1].type = C_STRING;
464 sprintf(buf, "%d", params->h);
465 ret[1].sval = dupstr(buf);
468 ret[2].name = "Recursion depth";
469 ret[2].type = C_STRING;
470 sprintf(buf, "%d", params->rec);
471 ret[2].sval = dupstr(buf);
482 static game_params *custom_params(config_item *cfg)
484 game_params *ret = snew(game_params);
486 ret->w = atoi(cfg[0].sval);
487 ret->h = atoi(cfg[1].sval);
488 ret->rec = atoi(cfg[2].sval);
493 static char *validate_params(game_params *params, int full)
495 if (params->w < 4 || params->h < 4)
496 return "Width and height must both be at least 4";
498 return "Recursion depth can't be negative";
502 /* We're going to store a list of current candidate squares for lighting.
503 * Each square gets a 'score', which tells us how adding that square right
504 * now would affect the length of the solution loop. We're trying to
505 * maximise that quantity so will bias our random selection of squares to
506 * light towards those with high scores */
513 static int get_square_cmpfn(void *v1, void *v2)
515 struct square *s1 = (struct square *)v1;
516 struct square *s2 = (struct square *)v2;
530 static int square_sort_cmpfn(void *v1, void *v2)
532 struct square *s1 = (struct square *)v1;
533 struct square *s2 = (struct square *)v2;
536 r = s2->score - s1->score;
541 r = s1->random - s2->random;
547 * It's _just_ possible that two squares might have been given
548 * the same random value. In that situation, fall back to
549 * comparing based on the coordinates. This introduces a tiny
550 * directional bias, but not a significant one.
552 return get_square_cmpfn(v1, v2);
555 static void print_tree(tree234 *tree)
560 printf("Print tree:\n");
561 while (i < count234(tree)) {
562 s = (struct square *)index234(tree, i);
564 printf(" [%d,%d], %d, %d\n", s->x, s->y, s->score, s->random);
570 enum { SQUARE_LIT, SQUARE_UNLIT };
572 #define SQUARE_STATE(i, j) \
573 (((i) < 0 || (i) >= params->w || \
574 (j) < 0 || (j) >= params->h) ? \
575 SQUARE_UNLIT : LV_SQUARE_STATE(i,j))
577 #define LV_SQUARE_STATE(i, j) board[(i) + params->w * (j)]
579 static void print_board(const game_params *params, const char *board)
585 for (i = 0; i < params->w; i++) {
589 for (j = 0; j < params->h; j++) {
591 for (i = 0; i < params->w; i++) {
592 printf("%c", SQUARE_STATE(i, j) ? ' ' : 'O');
599 static char *new_fullyclued_board(game_params *params, random_state *rs)
605 game_state *state = &s;
606 int board_area = SQUARE_COUNT(params);
609 struct square *square, *tmpsquare, *sq;
610 struct square square_pos;
612 /* These will contain exactly the same information, sorted into different
614 tree234 *lightable_squares_sorted, *lightable_squares_gettable;
616 #define SQUARE_REACHABLE(i,j) \
617 (t = (SQUARE_STATE(i-1, j) == SQUARE_LIT || \
618 SQUARE_STATE(i+1, j) == SQUARE_LIT || \
619 SQUARE_STATE(i, j-1) == SQUARE_LIT || \
620 SQUARE_STATE(i, j+1) == SQUARE_LIT), \
621 /* printf("SQUARE_REACHABLE(%d,%d) = %d\n", i, j, t), */ \
625 /* One situation in which we may not light a square is if that'll leave one
626 * square above/below and one left/right of us unlit, separated by a lit
627 * square diagnonal from us */
628 #define SQUARE_DIAGONAL_VIOLATION(i, j, h, v) \
629 (t = (SQUARE_STATE((i)+(h), (j)) == SQUARE_UNLIT && \
630 SQUARE_STATE((i), (j)+(v)) == SQUARE_UNLIT && \
631 SQUARE_STATE((i)+(h), (j)+(v)) == SQUARE_LIT), \
632 /* t ? printf("SQUARE_DIAGONAL_VIOLATION(%d, %d, %d, %d)\n",
636 /* We also may not light a square if it will form a loop of lit squares
637 * around some unlit squares, as then the game soln won't have a single
639 #define SQUARE_LOOP_VIOLATION(i, j, lit1, lit2) \
640 (SQUARE_STATE((i)+1, (j)) == lit1 && \
641 SQUARE_STATE((i)-1, (j)) == lit1 && \
642 SQUARE_STATE((i), (j)+1) == lit2 && \
643 SQUARE_STATE((i), (j)-1) == lit2)
645 #define CAN_LIGHT_SQUARE(i, j) \
646 (SQUARE_REACHABLE(i, j) && \
647 !SQUARE_DIAGONAL_VIOLATION(i, j, -1, -1) && \
648 !SQUARE_DIAGONAL_VIOLATION(i, j, +1, -1) && \
649 !SQUARE_DIAGONAL_VIOLATION(i, j, -1, +1) && \
650 !SQUARE_DIAGONAL_VIOLATION(i, j, +1, +1) && \
651 !SQUARE_LOOP_VIOLATION(i, j, SQUARE_LIT, SQUARE_UNLIT) && \
652 !SQUARE_LOOP_VIOLATION(i, j, SQUARE_UNLIT, SQUARE_LIT))
654 #define IS_LIGHTING_CANDIDATE(i, j) \
655 (SQUARE_STATE(i, j) == SQUARE_UNLIT && \
656 CAN_LIGHT_SQUARE(i,j))
658 /* The 'score' of a square reflects its current desirability for selection
659 * as the next square to light. We want to encourage moving into uncharted
660 * areas so we give scores according to how many of the square's neighbours
661 * are currently unlit. */
668 #define SQUARE_SCORE(i,j) \
669 (2*((SQUARE_STATE(i-1, j) == SQUARE_UNLIT) + \
670 (SQUARE_STATE(i+1, j) == SQUARE_UNLIT) + \
671 (SQUARE_STATE(i, j-1) == SQUARE_UNLIT) + \
672 (SQUARE_STATE(i, j+1) == SQUARE_UNLIT)) - 4)
674 /* When a square gets lit, this defines how far away from that square we
675 * need to go recomputing scores */
676 #define SCORE_DISTANCE 1
678 board = snewn(board_area, char);
679 clues = snewn(board_area, char);
681 state->h = params->h;
682 state->w = params->w;
683 state->clues = clues;
686 memset(board, SQUARE_UNLIT, board_area);
688 /* Seed the board with a single lit square near the middle */
691 if (params->w & 1 && random_bits(rs, 1))
693 if (params->h & 1 && random_bits(rs, 1))
696 LV_SQUARE_STATE(i, j) = SQUARE_LIT;
698 /* We need a way of favouring squares that will increase our loopiness.
699 * We do this by maintaining a list of all candidate squares sorted by
700 * their score and choose randomly from that with appropriate skew.
701 * In order to avoid consistently biasing towards particular squares, we
702 * need the sort order _within_ each group of scores to be completely
703 * random. But it would be abusing the hospitality of the tree234 data
704 * structure if our comparison function were nondeterministic :-). So with
705 * each square we associate a random number that does not change during a
706 * particular run of the generator, and use that as a secondary sort key.
707 * Yes, this means we will be biased towards particular random squares in
708 * any one run but that doesn't actually matter. */
710 lightable_squares_sorted = newtree234(square_sort_cmpfn);
711 lightable_squares_gettable = newtree234(get_square_cmpfn);
712 #define ADD_SQUARE(s) \
714 /* printf("ADD SQUARE: [%d,%d], %d, %d\n",
715 s->x, s->y, s->score, s->random);*/ \
716 sq = add234(lightable_squares_sorted, s); \
718 sq = add234(lightable_squares_gettable, s); \
722 #define REMOVE_SQUARE(s) \
724 /* printf("DELETE SQUARE: [%d,%d], %d, %d\n",
725 s->x, s->y, s->score, s->random);*/ \
726 sq = del234(lightable_squares_sorted, s); \
728 sq = del234(lightable_squares_gettable, s); \
732 #define HANDLE_DIR(a, b) \
733 square = snew(struct square); \
734 square->x = (i)+(a); \
735 square->y = (j)+(b); \
737 square->random = random_bits(rs, 31); \
745 /* Light squares one at a time until the board is interesting enough */
748 /* We have count234(lightable_squares) possibilities, and in
749 * lightable_squares_sorted they are sorted with the most desirable
751 c = count234(lightable_squares_sorted);
754 assert(c == count234(lightable_squares_gettable));
756 /* Check that the best square available is any good */
757 square = (struct square *)index234(lightable_squares_sorted, 0);
760 if (square->score <= 0)
763 print_tree(lightable_squares_sorted);
764 assert(square->score == SQUARE_SCORE(square->x, square->y));
765 assert(SQUARE_STATE(square->x, square->y) == SQUARE_UNLIT);
766 assert(square->x >= 0 && square->x < params->w);
767 assert(square->y >= 0 && square->y < params->h);
768 /* printf("LIGHT SQUARE: [%d,%d], score = %d\n", square->x, square->y, square->score); */
770 /* Update data structures */
771 LV_SQUARE_STATE(square->x, square->y) = SQUARE_LIT;
772 REMOVE_SQUARE(square);
774 print_board(params, board);
776 /* We might have changed the score of any squares up to 2 units away in
778 for (b = -SCORE_DISTANCE; b <= SCORE_DISTANCE; b++) {
779 for (a = -SCORE_DISTANCE; a <= SCORE_DISTANCE; a++) {
782 square_pos.x = square->x + a;
783 square_pos.y = square->y + b;
784 /* printf("Refreshing score for [%d,%d]:\n", square_pos.x, square_pos.y); */
785 if (square_pos.x < 0 || square_pos.x >= params->w ||
786 square_pos.y < 0 || square_pos.y >= params->h) {
787 /* printf(" Out of bounds\n"); */
790 tmpsquare = find234(lightable_squares_gettable, &square_pos,
793 /* printf(" Removing\n"); */
794 assert(tmpsquare->x == square_pos.x);
795 assert(tmpsquare->y == square_pos.y);
796 assert(SQUARE_STATE(tmpsquare->x, tmpsquare->y) ==
798 REMOVE_SQUARE(tmpsquare);
800 /* printf(" Creating\n"); */
801 tmpsquare = snew(struct square);
802 tmpsquare->x = square_pos.x;
803 tmpsquare->y = square_pos.y;
804 tmpsquare->random = random_bits(rs, 31);
806 tmpsquare->score = SQUARE_SCORE(tmpsquare->x, tmpsquare->y);
808 if (IS_LIGHTING_CANDIDATE(tmpsquare->x, tmpsquare->y)) {
809 /* printf(" Adding\n"); */
810 ADD_SQUARE(tmpsquare);
812 /* printf(" Destroying\n"); */
818 /* printf("\n\n"); */
821 while ((square = delpos234(lightable_squares_gettable, 0)) != NULL)
823 freetree234(lightable_squares_gettable);
824 freetree234(lightable_squares_sorted);
826 /* Copy out all the clues */
827 for (j = 0; j < params->h; ++j) {
828 for (i = 0; i < params->w; ++i) {
829 c = SQUARE_STATE(i, j);
830 LV_CLUE_AT(state, i, j) = '0';
831 if (SQUARE_STATE(i-1, j) != c) ++LV_CLUE_AT(state, i, j);
832 if (SQUARE_STATE(i+1, j) != c) ++LV_CLUE_AT(state, i, j);
833 if (SQUARE_STATE(i, j-1) != c) ++LV_CLUE_AT(state, i, j);
834 if (SQUARE_STATE(i, j+1) != c) ++LV_CLUE_AT(state, i, j);
842 static solver_state *solve_game_rec(const solver_state *sstate);
844 static int game_has_unique_soln(const game_state *state)
847 solver_state *sstate_new;
848 solver_state *sstate = new_solver_state((game_state *)state);
850 sstate_new = solve_game_rec(sstate);
852 ret = (sstate_new->solver_status == SOLVER_SOLVED);
854 free_solver_state(sstate_new);
855 free_solver_state(sstate);
860 /* Remove clues one at a time at random. */
861 static game_state *remove_clues(game_state *state, random_state *rs)
863 int *square_list, squares;
864 game_state *ret = dup_game(state), *saved_ret;
867 /* We need to remove some clues. We'll do this by forming a list of all
868 * available equivalence classes, shuffling it, then going along one at a
869 * time clearing every member of each equivalence class, where removing a
870 * class doesn't render the board unsolvable. */
871 squares = state->w * state->h;
872 square_list = snewn(squares, int);
873 for (n = 0; n < squares; ++n) {
877 shuffle(square_list, squares, sizeof(int), rs);
879 for (n = 0; n < squares; ++n) {
880 saved_ret = dup_game(ret);
881 LV_CLUE_AT(ret, square_list[n] % state->w,
882 square_list[n] / state->w) = ' ';
883 if (game_has_unique_soln(ret)) {
884 free_game(saved_ret);
895 static char *validate_desc(game_params *params, char *desc);
897 static char *new_game_desc(game_params *params, random_state *rs,
898 char **aux, int interactive)
900 /* solution and description both use run-length encoding in obvious ways */
902 char *description = snewn(SQUARE_COUNT(params) + 1, char);
903 char *dp = description;
906 game_state *state = snew(game_state), *state_new;
908 state->h = params->h;
909 state->w = params->w;
911 state->hl = snewn(HL_COUNT(params), char);
912 state->vl = snewn(VL_COUNT(params), char);
913 memset(state->hl, LINE_UNKNOWN, HL_COUNT(params));
914 memset(state->vl, LINE_UNKNOWN, VL_COUNT(params));
916 state->solved = state->cheated = FALSE;
917 state->recursion_depth = params->rec;
919 /* Get a new random solvable board with all its clues filled in. Yes, this
920 * can loop for ever if the params are suitably unfavourable, but
921 * preventing games smaller than 4x4 seems to stop this happening */
923 state->clues = new_fullyclued_board(params, rs);
924 } while (!game_has_unique_soln(state));
926 state_new = remove_clues(state, rs);
931 for (j = 0; j < params->h; ++j) {
932 for (i = 0; i < params->w; ++i) {
933 if (CLUE_AT(state, i, j) == ' ') {
934 if (empty_count > 25) {
935 dp += sprintf(dp, "%c", (int)(empty_count + 'a' - 1));
941 dp += sprintf(dp, "%c", (int)(empty_count + 'a' - 1));
944 dp += sprintf(dp, "%c", (int)(CLUE_AT(state, i, j)));
949 dp += sprintf(dp, "%c", (int)(empty_count + 'a' - 1));
952 retval = dupstr(description);
955 assert(!validate_desc(params, retval));
960 /* We require that the params pass the test in validate_params and that the
961 * description fills the entire game area */
962 static char *validate_desc(game_params *params, char *desc)
966 for (; *desc; ++desc) {
967 if (*desc >= '0' && *desc <= '9') {
972 count += *desc - 'a' + 1;
975 return "Unknown character in description";
978 if (count < SQUARE_COUNT(params))
979 return "Description too short for board size";
980 if (count > SQUARE_COUNT(params))
981 return "Description too long for board size";
986 static game_state *new_game(midend *me, game_params *params, char *desc)
989 game_state *state = snew(game_state);
990 int empties_to_make = 0;
992 const char *dp = desc;
994 state->recursion_depth = params->rec;
996 state->h = params->h;
997 state->w = params->w;
999 state->clues = snewn(SQUARE_COUNT(params), char);
1000 state->hl = snewn(HL_COUNT(params), char);
1001 state->vl = snewn(VL_COUNT(params), char);
1003 state->solved = state->cheated = FALSE;
1005 for (j = 0 ; j < params->h; ++j) {
1006 for (i = 0 ; i < params->w; ++i) {
1007 if (empties_to_make) {
1009 LV_CLUE_AT(state, i, j) = ' ';
1015 if (n >=0 && n < 10) {
1016 LV_CLUE_AT(state, i, j) = *dp;
1020 LV_CLUE_AT(state, i, j) = ' ';
1021 empties_to_make = n - 1;
1027 memset(state->hl, LINE_UNKNOWN, HL_COUNT(params));
1028 memset(state->vl, LINE_UNKNOWN, VL_COUNT(params));
1033 enum { LOOP_NONE=0, LOOP_SOLN, LOOP_NOT_SOLN };
1035 /* Starting at dot [i,j] moves around 'state' removing lines until it's clear
1036 * whether or not the starting dot was on a loop. Returns boolean specifying
1037 * whether a loop was found. loop_status calls this and assumes that if state
1038 * has any lines set, this function will always remove at least one. */
1039 static int destructively_find_loop(game_state *state)
1041 int a, b, i, j, new_i, new_j, n;
1044 lp = (char *)memchr(state->hl, LINE_YES, HL_COUNT(state));
1046 /* We know we're going to return false but we have to fulfil our
1048 lp = (char *)memchr(state->vl, LINE_YES, VL_COUNT(state));
1060 assert(i + j * state->w == n); /* because I'm feeling stupid */
1061 /* Save start position */
1065 /* Delete one line from the potential loop */
1066 if (LEFTOF_DOT(state, i, j) == LINE_YES) {
1067 LV_LEFTOF_DOT(state, i, j) = LINE_NO;
1069 } else if (ABOVE_DOT(state, i, j) == LINE_YES) {
1070 LV_ABOVE_DOT(state, i, j) = LINE_NO;
1072 } else if (RIGHTOF_DOT(state, i, j) == LINE_YES) {
1073 LV_RIGHTOF_DOT(state, i, j) = LINE_NO;
1075 } else if (BELOW_DOT(state, i, j) == LINE_YES) {
1076 LV_BELOW_DOT(state, i, j) = LINE_NO;
1083 /* From the current position of [i,j] there needs to be exactly one
1087 #define HANDLE_DIR(dir_dot, x, y) \
1088 if (dir_dot(state, i, j) == LINE_YES) { \
1089 if (new_i != -1 || new_j != -1) \
1093 LV_##dir_dot(state, i, j) = LINE_NO; \
1095 HANDLE_DIR(ABOVE_DOT, 0, -1);
1096 HANDLE_DIR(BELOW_DOT, 0, +1);
1097 HANDLE_DIR(LEFTOF_DOT, -1, 0);
1098 HANDLE_DIR(RIGHTOF_DOT, +1, 0);
1100 if (new_i == -1 || new_j == -1) {
1106 } while (i != a || j != b);
1111 static int loop_status(game_state *state)
1114 game_state *tmpstate;
1115 int loop_found = FALSE, non_loop_found = FALSE, any_lines_found = FALSE;
1117 #define BAD_LOOP_FOUND \
1118 do { free_game(tmpstate); return LOOP_NOT_SOLN; } while(0)
1120 /* Repeatedly look for loops until we either run out of lines to consider
1121 * or discover for sure that the board fails on the grounds of having no
1123 tmpstate = dup_game(state);
1126 if (!memchr(tmpstate->hl, LINE_YES, HL_COUNT(tmpstate)) &&
1127 !memchr(tmpstate->vl, LINE_YES, VL_COUNT(tmpstate))) {
1130 any_lines_found = TRUE;
1134 if (destructively_find_loop(tmpstate)) {
1139 non_loop_found = TRUE;
1143 free_game(tmpstate);
1145 if (!any_lines_found)
1148 if (non_loop_found) {
1149 assert(!loop_found); /* should have dealt with this already */
1153 /* Check that every clue is satisfied */
1154 for (j = 0; j < state->h; ++j) {
1155 for (i = 0; i < state->w; ++i) {
1156 n = CLUE_AT(state, i, j);
1158 if (square_order(state, i, j, LINE_YES) != n - '0') {
1159 return LOOP_NOT_SOLN;
1168 /* Sums the lengths of the numbers in range [0,n) */
1169 /* See equivalent function in solo.c for justification of this. */
1170 static int len_0_to_n(int n)
1172 int len = 1; /* Counting 0 as a bit of a special case */
1175 for (i = 1; i < n; i *= 10) {
1176 len += max(n - i, 0);
1182 static char *encode_solve_move(const game_state *state)
1186 /* This is going to return a string representing the moves needed to set
1187 * every line in a grid to be the same as the ones in 'state'. The exact
1188 * length of this string is predictable. */
1190 len = 1; /* Count the 'S' prefix */
1191 /* Numbers in horizontal lines */
1192 /* Horizontal lines, x position */
1193 len += len_0_to_n(state->w) * (state->h + 1);
1194 /* Horizontal lines, y position */
1195 len += len_0_to_n(state->h + 1) * (state->w);
1196 /* Vertical lines, y position */
1197 len += len_0_to_n(state->h) * (state->w + 1);
1198 /* Vertical lines, x position */
1199 len += len_0_to_n(state->w + 1) * (state->h);
1200 /* For each line we also have two letters and a comma */
1201 len += 3 * (HL_COUNT(state) + VL_COUNT(state));
1203 ret = snewn(len + 1, char);
1206 p += sprintf(p, "S");
1208 for (j = 0; j < state->h + 1; ++j) {
1209 for (i = 0; i < state->w; ++i) {
1210 switch (RIGHTOF_DOT(state, i, j)) {
1212 p += sprintf(p, "%d,%dhy", i, j);
1215 p += sprintf(p, "%d,%dhn", i, j);
1218 /* I'm going to forgive this because I think the results
1220 /* assert(!"Solver produced incomplete solution!"); */
1225 for (j = 0; j < state->h; ++j) {
1226 for (i = 0; i < state->w + 1; ++i) {
1227 switch (BELOW_DOT(state, i, j)) {
1229 p += sprintf(p, "%d,%dvy", i, j);
1232 p += sprintf(p, "%d,%dvn", i, j);
1235 /* I'm going to forgive this because I think the results
1237 /* assert(!"Solver produced incomplete solution!"); */
1242 /* No point in doing sums like that if they're going to be wrong */
1243 assert(strlen(ret) <= (size_t)len);
1247 /* BEGIN SOLVER IMPLEMENTATION */
1249 /* For each pair of lines through each dot we store a bit for whether
1250 * exactly one of those lines is ON, and in separate arrays we store whether
1251 * at least one is on and whether at most 1 is on. (If we know both or
1252 * neither is on that's already stored more directly.) That's six bits per
1253 * dot. Bit number n represents the lines shown in dot_type_dirs[n]. */
1264 #define OPP_DLINE(dline) (dline ^ 1)
1267 #define SQUARE_DLINES \
1268 HANDLE_DLINE(DLINE_UL, RIGHTOF_SQUARE, BELOW_SQUARE, 1, 1); \
1269 HANDLE_DLINE(DLINE_UR, LEFTOF_SQUARE, BELOW_SQUARE, 0, 1); \
1270 HANDLE_DLINE(DLINE_DL, RIGHTOF_SQUARE, ABOVE_SQUARE, 1, 0); \
1271 HANDLE_DLINE(DLINE_DR, LEFTOF_SQUARE, ABOVE_SQUARE, 0, 0);
1273 #define DOT_DLINES \
1274 HANDLE_DLINE(DLINE_VERT, ABOVE_DOT, BELOW_DOT); \
1275 HANDLE_DLINE(DLINE_HORIZ, LEFTOF_DOT, RIGHTOF_DOT); \
1276 HANDLE_DLINE(DLINE_UL, ABOVE_DOT, LEFTOF_DOT); \
1277 HANDLE_DLINE(DLINE_UR, ABOVE_DOT, RIGHTOF_DOT); \
1278 HANDLE_DLINE(DLINE_DL, BELOW_DOT, LEFTOF_DOT); \
1279 HANDLE_DLINE(DLINE_DR, BELOW_DOT, RIGHTOF_DOT);
1281 static void array_setall(char *array, char from, char to, int len)
1283 char *p = array, *p_old = p;
1284 int len_remaining = len;
1286 while ((p = memchr(p, from, len_remaining))) {
1288 len_remaining -= p - p_old;
1294 static int game_states_equal(const game_state *state1,
1295 const game_state *state2)
1297 /* This deliberately doesn't check _all_ fields, just the ones that make a
1298 * game state 'interesting' from the POV of the solver */
1299 /* XXX review this */
1300 if (state1 == state2)
1303 if (!state1 || !state2)
1306 if (state1->w != state2->w || state1->h != state2->h)
1309 if (memcmp(state1->hl, state2->hl, HL_COUNT(state1)))
1312 if (memcmp(state1->vl, state2->vl, VL_COUNT(state1)))
1318 static int solver_states_equal(const solver_state *sstate1,
1319 const solver_state *sstate2)
1328 if (!game_states_equal(sstate1->state, sstate2->state)) {
1332 /* XXX fields missing, needs review */
1333 /* XXX we're deliberately not looking at solver_state as it's only a cache */
1335 if (memcmp(sstate1->dot_atleastone, sstate2->dot_atleastone,
1336 DOT_COUNT(sstate1->state))) {
1340 if (memcmp(sstate1->dot_atmostone, sstate2->dot_atmostone,
1341 DOT_COUNT(sstate1->state))) {
1345 /* handle dline_identical here */
1350 static void dot_setall_dlines(solver_state *sstate, enum dline dl, int i, int j,
1351 enum line_state line_old, enum line_state line_new)
1353 game_state *state = sstate->state;
1355 /* First line in dline */
1360 if (j > 0 && ABOVE_DOT(state, i, j) == line_old)
1361 LV_ABOVE_DOT(state, i, j) = line_new;
1365 if (j <= (state)->h && BELOW_DOT(state, i, j) == line_old)
1366 LV_BELOW_DOT(state, i, j) = line_new;
1369 if (i > 0 && LEFTOF_DOT(state, i, j) == line_old)
1370 LV_LEFTOF_DOT(state, i, j) = line_new;
1374 /* Second line in dline */
1378 if (i > 0 && LEFTOF_DOT(state, i, j) == line_old)
1379 LV_LEFTOF_DOT(state, i, j) = line_new;
1384 if (i <= (state)->w && RIGHTOF_DOT(state, i, j) == line_old)
1385 LV_RIGHTOF_DOT(state, i, j) = line_new;
1388 if (j <= (state)->h && BELOW_DOT(state, i, j) == line_old)
1389 LV_BELOW_DOT(state, i, j) = line_new;
1394 static void update_solver_status(solver_state *sstate)
1396 if (sstate->solver_status == SOLVER_INCOMPLETE) {
1397 switch (loop_status(sstate->state)) {
1399 sstate->solver_status = SOLVER_INCOMPLETE;
1402 if (sstate->solver_status != SOLVER_AMBIGUOUS)
1403 sstate->solver_status = SOLVER_SOLVED;
1406 sstate->solver_status = SOLVER_MISTAKE;
1413 /* This will return a dynamically allocated solver_state containing the (more)
1415 static solver_state *solve_game_rec(const solver_state *sstate_start)
1418 int current_yes, current_no, desired;
1419 solver_state *sstate, *sstate_saved, *sstate_tmp;
1422 solver_state *sstate_rec_solved;
1423 int recursive_soln_count;
1426 printf("solve_game_rec: recursion_remaining = %d\n",
1427 sstate_start->recursion_remaining);
1430 sstate = dup_solver_state((solver_state *)sstate_start);
1433 text = game_text_format(sstate->state);
1434 printf("%s\n", text);
1438 #define RETURN_IF_SOLVED \
1440 update_solver_status(sstate); \
1441 if (sstate->solver_status != SOLVER_INCOMPLETE) { \
1442 free_solver_state(sstate_saved); \
1447 sstate_saved = NULL;
1450 nonrecursive_solver:
1453 sstate_saved = dup_solver_state(sstate);
1455 /* First we do the 'easy' work, that might cause concrete results */
1457 /* Per-square deductions */
1458 for (j = 0; j < sstate->state->h; ++j) {
1459 for (i = 0; i < sstate->state->w; ++i) {
1460 /* Begin rules that look at the clue (if there is one) */
1461 desired = CLUE_AT(sstate->state, i, j);
1464 desired = desired - '0';
1465 current_yes = square_order(sstate->state, i, j, LINE_YES);
1466 current_no = square_order(sstate->state, i, j, LINE_NO);
1468 if (desired <= current_yes) {
1469 square_setall(sstate->state, i, j, LINE_UNKNOWN, LINE_NO);
1473 if (4 - desired <= current_no) {
1474 square_setall(sstate->state, i, j, LINE_UNKNOWN, LINE_YES);
1481 /* Per-dot deductions */
1482 for (j = 0; j < sstate->state->h + 1; ++j) {
1483 for (i = 0; i < sstate->state->w + 1; ++i) {
1484 switch (dot_order(sstate->state, i, j, LINE_YES)) {
1486 if (dot_order(sstate->state, i, j, LINE_NO) == 3) {
1487 dot_setall(sstate->state, i, j, LINE_UNKNOWN, LINE_NO);
1491 switch (dot_order(sstate->state, i, j, LINE_NO)) {
1492 #define H1(dline, dir1_dot, dir2_dot, dot_howmany) \
1493 if (dir1_dot(sstate->state, i, j) == LINE_UNKNOWN) { \
1494 if (dir2_dot(sstate->state, i, j) == LINE_UNKNOWN){ \
1495 sstate->dot_howmany \
1496 [i + (sstate->state->w + 1) * j] |= 1<<dline; \
1500 #define HANDLE_DLINE(dline, dir1_dot, dir2_dot) \
1501 H1(dline, dir1_dot, dir2_dot, dot_atleastone)
1502 /* 1 yes, 1 no, so exactly one of unknowns is yes */
1507 #define HANDLE_DLINE(dline, dir1_dot, dir2_dot) \
1508 H1(dline, dir1_dot, dir2_dot, dot_atmostone)
1509 /* 1 yes, fewer than 2 no, so at most one of
1510 * unknowns is yes */
1515 case 2: /* 1 yes, 2 no */
1516 dot_setall(sstate->state, i, j,
1517 LINE_UNKNOWN, LINE_YES);
1523 dot_setall(sstate->state, i, j, LINE_UNKNOWN, LINE_NO);
1525 #define HANDLE_DLINE(dline, dir1_dot, dir2_dot) \
1526 if (sstate->dot_atleastone \
1527 [i + (sstate->state->w + 1) * j] & 1<<dline) { \
1528 sstate->dot_atmostone \
1529 [i + (sstate->state->w + 1) * j] |= 1<<OPP_DLINE(dline); \
1531 /* If at least one of a dline in a dot is YES, at most one of
1532 * the opposite dline to that dot must be YES. */
1538 /* More obscure per-square operations */
1539 for (j = 0; j < sstate->state->h; ++j) {
1540 for (i = 0; i < sstate->state->w; ++i) {
1541 #define H1(dline, dir1_sq, dir2_sq, a, b, dot_howmany, line_query, line_set) \
1542 if (sstate->dot_howmany[i+a + (sstate->state->w + 1) * (j+b)] &\
1544 t = dir1_sq(sstate->state, i, j); \
1545 if (t == line_query) \
1546 dir2_sq(sstate->state, i, j) = line_set; \
1548 t = dir2_sq(sstate->state, i, j); \
1549 if (t == line_query) \
1550 dir1_sq(sstate->state, i, j) = line_set; \
1553 #define HANDLE_DLINE(dline, dir1_sq, dir2_sq, a, b) \
1554 H1(dline, dir1_sq, dir2_sq, a, b, dot_atmostone, \
1556 /* If at most one of the DLINE is on, and one is definitely on,
1557 * set the other to definitely off */
1561 #define HANDLE_DLINE(dline, dir1_sq, dir2_sq, a, b) \
1562 H1(dline, dir1_sq, dir2_sq, a, b, dot_atleastone, \
1564 /* If at least one of the DLINE is on, and one is definitely
1565 * off, set the other to definitely on */
1570 switch (CLUE_AT(sstate->state, i, j)) {
1573 #define HANDLE_DLINE(dline, dir1_sq, dir2_sq, a, b) \
1574 /* At most one of any DLINE can be set */ \
1575 sstate->dot_atmostone \
1576 [i+a + (sstate->state->w + 1) * (j+b)] |= 1<<dline; \
1577 /* This DLINE provides enough YESes to solve the clue */\
1578 if (sstate->dot_atleastone \
1579 [i+a + (sstate->state->w + 1) * (j+b)] & \
1581 dot_setall_dlines(sstate, OPP_DLINE(dline), \
1583 LINE_UNKNOWN, LINE_NO); \
1589 #define H1(dline, dot_at1one, dot_at2one, a, b) \
1590 if (sstate->dot_at1one \
1591 [i+a + (sstate->state->w + 1) * (j+b)] & \
1593 sstate->dot_at2one \
1594 [i+(1-a) + (sstate->state->w + 1) * (j+(1-b))] |= \
1595 1<<OPP_DLINE(dline); \
1597 #define HANDLE_DLINE(dline, dir1_sq, dir2_sq, a, b) \
1598 H1(dline, dot_atleastone, dot_atmostone, a, b); \
1599 H1(dline, dot_atmostone, dot_atleastone, a, b);
1600 /* If at least one of one DLINE is set, at most one of
1601 * the opposing one is and vice versa */
1608 #define HANDLE_DLINE(dline, dir1_sq, dir2_sq, a, b) \
1609 /* At least one of any DLINE can be set */ \
1610 sstate->dot_atleastone \
1611 [i+a + (sstate->state->w + 1) * (j+b)] |= 1<<dline; \
1612 /* This DLINE provides enough NOs to solve the clue */ \
1613 if (sstate->dot_atmostone \
1614 [i+a + (sstate->state->w + 1) * (j+b)] & \
1616 dot_setall_dlines(sstate, OPP_DLINE(dline), \
1618 LINE_UNKNOWN, LINE_YES); \
1627 if (solver_states_equal(sstate, sstate_saved)) {
1628 int edgecount = 0, clues = 0, satclues = 0, sm1clues = 0;
1632 * Go through the grid and update for all the new edges.
1633 * Since merge_dots() is idempotent, the simplest way to
1634 * do this is just to update for _all_ the edges.
1636 * Also, while we're here, we count the edges, count the
1637 * clues, count the satisfied clues, and count the
1638 * satisfied-minus-one clues.
1640 for (j = 0; j <= sstate->state->h; ++j) {
1641 for (i = 0; i <= sstate->state->w; ++i) {
1642 if (RIGHTOF_DOT(sstate->state, i, j) == LINE_YES) {
1643 merge_dots(sstate, i, j, i+1, j);
1646 if (BELOW_DOT(sstate->state, i, j) == LINE_YES) {
1647 merge_dots(sstate, i, j, i, j+1);
1651 if (CLUE_AT(sstate->state, i, j) != ' ') {
1652 int c = CLUE_AT(sstate->state, i, j) - '0';
1653 int o = square_order(sstate->state, i, j, LINE_YES);
1664 * Now go through looking for LINE_UNKNOWN edges which
1665 * connect two dots that are already in the same
1666 * equivalence class. If we find one, test to see if the
1667 * loop it would create is a solution.
1669 for (j = 0; j <= sstate->state->h; ++j) {
1670 for (i = 0; i <= sstate->state->w; ++i) {
1671 for (d = 0; d < 2; d++) {
1672 int i2, j2, eqclass, val;
1675 if (RIGHTOF_DOT(sstate->state, i, j) !=
1681 if (BELOW_DOT(sstate->state, i, j) !=
1688 eqclass = dsf_canonify(sstate->dotdsf,
1689 j * (sstate->state->w+1) + i);
1690 if (eqclass != dsf_canonify(sstate->dotdsf,
1691 j2 * (sstate->state->w+1) +
1695 val = LINE_NO; /* loop is bad until proven otherwise */
1698 * This edge would form a loop. Next
1699 * question: how long would the loop be?
1700 * Would it equal the total number of edges
1701 * (plus the one we'd be adding if we added
1704 if (sstate->looplen[eqclass] == edgecount + 1) {
1709 * This edge would form a loop which
1710 * took in all the edges in the entire
1711 * grid. So now we need to work out
1712 * whether it would be a valid solution
1713 * to the puzzle, which means we have to
1714 * check if it satisfies all the clues.
1715 * This means that every clue must be
1716 * either satisfied or satisfied-minus-
1717 * 1, and also that the number of
1718 * satisfied-minus-1 clues must be at
1719 * most two and they must lie on either
1720 * side of this edge.
1725 if (CLUE_AT(sstate->state, cx,cy) != ' ' &&
1726 square_order(sstate->state, cx,cy, LINE_YES) ==
1727 CLUE_AT(sstate->state, cx,cy) - '0' - 1)
1729 if (CLUE_AT(sstate->state, i, j) != ' ' &&
1730 square_order(sstate->state, i, j, LINE_YES) ==
1731 CLUE_AT(sstate->state, i, j) - '0' - 1)
1733 if (sm1clues == sm1_nearby &&
1734 sm1clues + satclues == clues)
1735 val = LINE_YES; /* loop is good! */
1739 * Right. Now we know that adding this edge
1740 * would form a loop, and we know whether
1741 * that loop would be a viable solution or
1744 * If adding this edge produces a solution,
1745 * then we know we've found _a_ solution but
1746 * we don't know that it's _the_ solution -
1747 * if it were provably the solution then
1748 * we'd have deduced this edge some time ago
1749 * without the need to do loop detection. So
1750 * in this state we return SOLVER_AMBIGUOUS,
1751 * which has the effect that hitting Solve
1752 * on a user-provided puzzle will fill in a
1753 * solution but using the solver to
1754 * construct new puzzles won't consider this
1755 * a reasonable deduction for the user to
1759 LV_RIGHTOF_DOT(sstate->state, i, j) = val;
1761 LV_BELOW_DOT(sstate->state, i, j) = val;
1762 if (val == LINE_YES) {
1763 sstate->solver_status = SOLVER_AMBIGUOUS;
1764 goto finished_loop_checking;
1770 finished_loop_checking:
1775 if (solver_states_equal(sstate, sstate_saved)) {
1776 /* Solver has stopped making progress so we terminate */
1777 free_solver_state(sstate_saved);
1781 free_solver_state(sstate_saved);
1784 if (sstate->solver_status == SOLVER_SOLVED ||
1785 sstate->solver_status == SOLVER_AMBIGUOUS) {
1786 /* s/LINE_UNKNOWN/LINE_NO/g */
1787 array_setall(sstate->state->hl, LINE_UNKNOWN, LINE_NO,
1788 HL_COUNT(sstate->state));
1789 array_setall(sstate->state->vl, LINE_UNKNOWN, LINE_NO,
1790 VL_COUNT(sstate->state));
1794 /* Perform recursive calls */
1795 if (sstate->recursion_remaining) {
1796 sstate->recursion_remaining--;
1798 sstate_saved = dup_solver_state(sstate);
1800 recursive_soln_count = 0;
1801 sstate_rec_solved = NULL;
1803 /* Memory management:
1804 * sstate_saved won't be modified but needs to be freed when we have
1806 * sstate is expected to contain our 'best' solution by the time we
1807 * finish this section of code. It's the thing we'll try adding lines
1808 * to, seeing if they make it more solvable.
1809 * If sstate_rec_solved is non-NULL, it will supersede sstate
1810 * eventually. sstate_tmp should not hold a value persistently.
1813 /* NB SOLVER_AMBIGUOUS is like SOLVER_SOLVED except the solver is aware
1814 * of the possibility of additional solutions. So as soon as we have a
1815 * SOLVER_AMBIGUOUS we can safely propagate it back to our caller, but
1816 * if we get a SOLVER_SOLVED we want to keep trying in case we find
1817 * further solutions and have to mark it ambiguous.
1820 #define DO_RECURSIVE_CALL(dir_dot) \
1821 if (dir_dot(sstate->state, i, j) == LINE_UNKNOWN) { \
1822 debug(("Trying " #dir_dot " at [%d,%d]\n", i, j)); \
1823 LV_##dir_dot(sstate->state, i, j) = LINE_YES; \
1824 sstate_tmp = solve_game_rec(sstate); \
1825 switch (sstate_tmp->solver_status) { \
1826 case SOLVER_AMBIGUOUS: \
1827 debug(("Solver ambiguous, returning\n")); \
1828 sstate_rec_solved = sstate_tmp; \
1829 goto finished_recursion; \
1830 case SOLVER_SOLVED: \
1831 switch (++recursive_soln_count) { \
1833 debug(("One solution found\n")); \
1834 sstate_rec_solved = sstate_tmp; \
1837 debug(("Ambiguous solutions found\n")); \
1838 free_solver_state(sstate_tmp); \
1839 sstate_rec_solved->solver_status = SOLVER_AMBIGUOUS;\
1840 goto finished_recursion; \
1842 assert(!"recursive_soln_count out of range"); \
1846 case SOLVER_MISTAKE: \
1847 debug(("Non-solution found\n")); \
1848 free_solver_state(sstate_tmp); \
1849 free_solver_state(sstate_saved); \
1850 LV_##dir_dot(sstate->state, i, j) = LINE_NO; \
1851 goto nonrecursive_solver; \
1852 case SOLVER_INCOMPLETE: \
1853 debug(("Recursive step inconclusive\n")); \
1854 free_solver_state(sstate_tmp); \
1857 free_solver_state(sstate); \
1858 sstate = dup_solver_state(sstate_saved); \
1861 for (j = 0; j < sstate->state->h + 1; ++j) {
1862 for (i = 0; i < sstate->state->w + 1; ++i) {
1863 /* Only perform recursive calls on 'loose ends' */
1864 if (dot_order(sstate->state, i, j, LINE_YES) == 1) {
1865 if (LEFTOF_DOT(sstate->state, i, j) == LINE_UNKNOWN)
1866 DO_RECURSIVE_CALL(LEFTOF_DOT);
1867 if (RIGHTOF_DOT(sstate->state, i, j) == LINE_UNKNOWN)
1868 DO_RECURSIVE_CALL(RIGHTOF_DOT);
1869 if (ABOVE_DOT(sstate->state, i, j) == LINE_UNKNOWN)
1870 DO_RECURSIVE_CALL(ABOVE_DOT);
1871 if (BELOW_DOT(sstate->state, i, j) == LINE_UNKNOWN)
1872 DO_RECURSIVE_CALL(BELOW_DOT);
1879 if (sstate_rec_solved) {
1880 free_solver_state(sstate);
1881 sstate = sstate_rec_solved;
1888 /* XXX bits of solver that may come in handy one day */
1890 #define HANDLE_DLINE(dline, dir1_dot, dir2_dot) \
1891 /* dline from this dot that's entirely unknown must have
1892 * both lines identical */ \
1893 if (dir1_dot(sstate->state, i, j) == LINE_UNKNOWN && \
1894 dir2_dot(sstate->state, i, j) == LINE_UNKNOWN) { \
1895 sstate->dline_identical[i + (sstate->state->w + 1) * j] |= \
1897 } else if (sstate->dline_identical[i +
1898 (sstate->state->w + 1) * j] &\
1900 /* If they're identical and one is known do the obvious
1902 t = dir1_dot(sstate->state, i, j); \
1903 if (t != LINE_UNKNOWN) \
1904 dir2_dot(sstate->state, i, j) = t; \
1906 t = dir2_dot(sstate->state, i, j); \
1907 if (t != LINE_UNKNOWN) \
1908 dir1_dot(sstate->state, i, j) = t; \
1916 #define HANDLE_DLINE(dline, dir1_sq, dir2_sq, a, b) \
1917 if (sstate->dline_identical[i+a + \
1918 (sstate->state->w + 1) * (j+b)] &\
1920 dir1_sq(sstate->state, i, j) = LINE_YES; \
1921 dir2_sq(sstate->state, i, j) = LINE_YES; \
1923 /* If two lines are the same they must be on */
1930 #define HANDLE_DLINE(dline, dir1_sq, dir2_sq, a, b) \
1931 if (sstate->dot_atmostone[i+a + (sstate->state->w + 1) * (j+b)] & \
1933 if (square_order(sstate->state, i, j, LINE_UNKNOWN) - 1 == \
1934 CLUE_AT(sstate->state, i, j) - '0') { \
1935 square_setall(sstate->state, i, j, LINE_UNKNOWN, LINE_YES); \
1936 /* XXX the following may overwrite known data! */ \
1937 dir1_sq(sstate->state, i, j) = LINE_UNKNOWN; \
1938 dir2_sq(sstate->state, i, j) = LINE_UNKNOWN; \
1946 #define HANDLE_DLINE(dline, dir1_sq, dir2_sq, a, b) \
1947 if (sstate->dline_identical[i+a +
1948 (sstate->state->w + 1) * (j+b)] &\
1950 dir1_sq(sstate->state, i, j) = LINE_NO; \
1951 dir2_sq(sstate->state, i, j) = LINE_NO; \
1953 /* If two lines are the same they must be off */
1958 static char *solve_game(game_state *state, game_state *currstate,
1959 char *aux, char **error)
1962 solver_state *sstate, *new_sstate;
1964 sstate = new_solver_state(state);
1965 new_sstate = solve_game_rec(sstate);
1967 if (new_sstate->solver_status == SOLVER_SOLVED) {
1968 soln = encode_solve_move(new_sstate->state);
1969 } else if (new_sstate->solver_status == SOLVER_AMBIGUOUS) {
1970 soln = encode_solve_move(new_sstate->state);
1971 /**error = "Solver found ambiguous solutions"; */
1973 soln = encode_solve_move(new_sstate->state);
1974 /**error = "Solver failed"; */
1977 free_solver_state(new_sstate);
1978 free_solver_state(sstate);
1983 static char *game_text_format(game_state *state)
1989 len = (2 * state->w + 2) * (2 * state->h + 1);
1990 rp = ret = snewn(len + 1, char);
1993 switch (ABOVE_SQUARE(state, i, j)) { \
1995 rp += sprintf(rp, " -"); \
1998 rp += sprintf(rp, " x"); \
2000 case LINE_UNKNOWN: \
2001 rp += sprintf(rp, " "); \
2004 assert(!"Illegal line state for HL");\
2008 switch (LEFTOF_SQUARE(state, i, j)) {\
2010 rp += sprintf(rp, "|"); \
2013 rp += sprintf(rp, "x"); \
2015 case LINE_UNKNOWN: \
2016 rp += sprintf(rp, " "); \
2019 assert(!"Illegal line state for VL");\
2022 for (j = 0; j < state->h; ++j) {
2023 for (i = 0; i < state->w; ++i) {
2026 rp += sprintf(rp, " \n");
2027 for (i = 0; i < state->w; ++i) {
2029 rp += sprintf(rp, "%c", (int)(CLUE_AT(state, i, j)));
2032 rp += sprintf(rp, "\n");
2034 for (i = 0; i < state->w; ++i) {
2037 rp += sprintf(rp, " \n");
2039 assert(strlen(ret) == len);
2043 static game_ui *new_ui(game_state *state)
2048 static void free_ui(game_ui *ui)
2052 static char *encode_ui(game_ui *ui)
2057 static void decode_ui(game_ui *ui, char *encoding)
2061 static void game_changed_state(game_ui *ui, game_state *oldstate,
2062 game_state *newstate)
2066 struct game_drawstate {
2073 static char *interpret_move(game_state *state, game_ui *ui, game_drawstate *ds,
2074 int x, int y, int button)
2079 char button_char = ' ';
2080 enum line_state old_state;
2082 button &= ~MOD_MASK;
2084 /* Around each line is a diamond-shaped region where points within that
2085 * region are closer to this line than any other. We assume any click
2086 * within a line's diamond was meant for that line. It would all be a lot
2087 * simpler if the / and % operators respected modulo arithmetic properly
2088 * for negative numbers. */
2093 /* Get the coordinates of the square the click was in */
2094 i = (x + TILE_SIZE) / TILE_SIZE - 1;
2095 j = (y + TILE_SIZE) / TILE_SIZE - 1;
2097 /* Get the precise position inside square [i,j] */
2098 p = (x + TILE_SIZE) % TILE_SIZE;
2099 q = (y + TILE_SIZE) % TILE_SIZE;
2101 /* After this bit of magic [i,j] will correspond to the point either above
2102 * or to the left of the line selected */
2104 if (TILE_SIZE - p > q) {
2107 hl_selected = FALSE;
2111 if (TILE_SIZE - q > p) {
2112 hl_selected = FALSE;
2123 if (i >= state->w || j >= state->h + 1)
2126 if (i >= state->w + 1 || j >= state->h)
2130 /* I think it's only possible to play this game with mouse clicks, sorry */
2131 /* Maybe will add mouse drag support some time */
2133 old_state = RIGHTOF_DOT(state, i, j);
2135 old_state = BELOW_DOT(state, i, j);
2139 switch (old_state) {
2153 switch (old_state) {
2168 sprintf(buf, "%d,%d%c%c", i, j, (int)(hl_selected ? 'h' : 'v'), (int)button_char);
2174 static game_state *execute_move(game_state *state, char *move)
2177 game_state *newstate = dup_game(state);
2179 if (move[0] == 'S') {
2181 newstate->cheated = TRUE;
2186 move = strchr(move, ',');
2190 move += strspn(move, "1234567890");
2191 switch (*(move++)) {
2193 if (i >= newstate->w || j > newstate->h)
2195 switch (*(move++)) {
2197 LV_RIGHTOF_DOT(newstate, i, j) = LINE_YES;
2200 LV_RIGHTOF_DOT(newstate, i, j) = LINE_NO;
2203 LV_RIGHTOF_DOT(newstate, i, j) = LINE_UNKNOWN;
2210 if (i > newstate->w || j >= newstate->h)
2212 switch (*(move++)) {
2214 LV_BELOW_DOT(newstate, i, j) = LINE_YES;
2217 LV_BELOW_DOT(newstate, i, j) = LINE_NO;
2220 LV_BELOW_DOT(newstate, i, j) = LINE_UNKNOWN;
2232 * Check for completion.
2234 i = 0; /* placate optimiser */
2235 for (j = 0; j <= newstate->h; j++) {
2236 for (i = 0; i < newstate->w; i++)
2237 if (LV_RIGHTOF_DOT(newstate, i, j) == LINE_YES)
2239 if (i < newstate->w)
2242 if (j <= newstate->h) {
2248 * We've found a horizontal edge at (i,j). Follow it round
2249 * to see if it's part of a loop.
2253 int order = dot_order(newstate, x, y, LINE_YES);
2255 goto completion_check_done;
2257 if (LEFTOF_DOT(newstate, x, y) == LINE_YES && prevdir != 'L') {
2260 } else if (RIGHTOF_DOT(newstate, x, y) == LINE_YES &&
2264 } else if (ABOVE_DOT(newstate, x, y) == LINE_YES &&
2268 } else if (BELOW_DOT(newstate, x, y) == LINE_YES &&
2273 assert(!"Can't happen"); /* dot_order guarantees success */
2278 if (x == i && y == j)
2282 if (x != i || y != j || looplen == 0)
2283 goto completion_check_done;
2286 * We've traced our way round a loop, and we know how many
2287 * line segments were involved. Count _all_ the line
2288 * segments in the grid, to see if the loop includes them
2292 for (j = 0; j <= newstate->h; j++)
2293 for (i = 0; i <= newstate->w; i++)
2294 count += ((RIGHTOF_DOT(newstate, i, j) == LINE_YES) +
2295 (BELOW_DOT(newstate, i, j) == LINE_YES));
2296 assert(count >= looplen);
2297 if (count != looplen)
2298 goto completion_check_done;
2301 * The grid contains one closed loop and nothing else.
2302 * Check that all the clues are satisfied.
2304 for (j = 0; j < newstate->h; ++j) {
2305 for (i = 0; i < newstate->w; ++i) {
2306 int n = CLUE_AT(newstate, i, j);
2308 if (square_order(newstate, i, j, LINE_YES) != n - '0') {
2309 goto completion_check_done;
2318 newstate->solved = TRUE;
2321 completion_check_done:
2325 free_game(newstate);
2329 /* ----------------------------------------------------------------------
2333 #define SIZE(d) ((d) * TILE_SIZE + 2 * BORDER + 1)
2335 static void game_compute_size(game_params *params, int tilesize,
2338 struct { int tilesize; } ads, *ds = &ads;
2339 ads.tilesize = tilesize;
2341 *x = SIZE(params->w);
2342 *y = SIZE(params->h);
2345 static void game_set_size(drawing *dr, game_drawstate *ds,
2346 game_params *params, int tilesize)
2348 ds->tilesize = tilesize;
2351 static float *game_colours(frontend *fe, game_state *state, int *ncolours)
2353 float *ret = snewn(4 * NCOLOURS, float);
2355 frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]);
2357 ret[COL_FOREGROUND * 3 + 0] = 0.0F;
2358 ret[COL_FOREGROUND * 3 + 1] = 0.0F;
2359 ret[COL_FOREGROUND * 3 + 2] = 0.0F;
2361 ret[COL_HIGHLIGHT * 3 + 0] = 1.0F;
2362 ret[COL_HIGHLIGHT * 3 + 1] = 1.0F;
2363 ret[COL_HIGHLIGHT * 3 + 2] = 1.0F;
2365 *ncolours = NCOLOURS;
2369 static game_drawstate *game_new_drawstate(drawing *dr, game_state *state)
2371 struct game_drawstate *ds = snew(struct game_drawstate);
2375 ds->hl = snewn(HL_COUNT(state), char);
2376 ds->vl = snewn(VL_COUNT(state), char);
2379 memset(ds->hl, LINE_UNKNOWN, HL_COUNT(state));
2380 memset(ds->vl, LINE_UNKNOWN, VL_COUNT(state));
2385 static void game_free_drawstate(drawing *dr, game_drawstate *ds)
2392 static void game_redraw(drawing *dr, game_drawstate *ds, game_state *oldstate,
2393 game_state *state, int dir, game_ui *ui,
2394 float animtime, float flashtime)
2397 int w = state->w, h = state->h;
2399 int line_colour, flash_changed;
2403 * The initial contents of the window are not guaranteed and
2404 * can vary with front ends. To be on the safe side, all games
2405 * should start by drawing a big background-colour rectangle
2406 * covering the whole window.
2408 draw_rect(dr, 0, 0, SIZE(state->w), SIZE(state->h), COL_BACKGROUND);
2411 for (j = 0; j < h + 1; ++j) {
2412 for (i = 0; i < w + 1; ++i) {
2414 BORDER + i * TILE_SIZE - LINEWIDTH/2,
2415 BORDER + j * TILE_SIZE - LINEWIDTH/2,
2416 LINEWIDTH, LINEWIDTH, COL_FOREGROUND);
2421 for (j = 0; j < h; ++j) {
2422 for (i = 0; i < w; ++i) {
2423 c[0] = CLUE_AT(state, i, j);
2426 BORDER + i * TILE_SIZE + TILE_SIZE/2,
2427 BORDER + j * TILE_SIZE + TILE_SIZE/2,
2428 FONT_VARIABLE, TILE_SIZE/2,
2429 ALIGN_VCENTRE | ALIGN_HCENTRE, COL_FOREGROUND, c);
2432 draw_update(dr, 0, 0,
2433 state->w * TILE_SIZE + 2*BORDER + 1,
2434 state->h * TILE_SIZE + 2*BORDER + 1);
2438 if (flashtime > 0 &&
2439 (flashtime <= FLASH_TIME/3 ||
2440 flashtime >= FLASH_TIME*2/3)) {
2441 flash_changed = !ds->flashing;
2442 ds->flashing = TRUE;
2443 line_colour = COL_HIGHLIGHT;
2445 flash_changed = ds->flashing;
2446 ds->flashing = FALSE;
2447 line_colour = COL_FOREGROUND;
2450 #define CROSS_SIZE (3 * LINEWIDTH / 2)
2452 #define CLEAR_VL(i, j) do { \
2454 BORDER + i * TILE_SIZE - CROSS_SIZE, \
2455 BORDER + j * TILE_SIZE + LINEWIDTH/2, \
2457 TILE_SIZE - LINEWIDTH, \
2460 BORDER + i * TILE_SIZE - CROSS_SIZE, \
2461 BORDER + j * TILE_SIZE - CROSS_SIZE, \
2463 TILE_SIZE + CROSS_SIZE*2); \
2466 #define CLEAR_HL(i, j) do { \
2468 BORDER + i * TILE_SIZE + LINEWIDTH/2, \
2469 BORDER + j * TILE_SIZE - CROSS_SIZE, \
2470 TILE_SIZE - LINEWIDTH, \
2474 BORDER + i * TILE_SIZE - CROSS_SIZE, \
2475 BORDER + j * TILE_SIZE - CROSS_SIZE, \
2476 TILE_SIZE + CROSS_SIZE*2, \
2480 /* Vertical lines */
2481 for (j = 0; j < h; ++j) {
2482 for (i = 0; i < w + 1; ++i) {
2483 switch (BELOW_DOT(state, i, j)) {
2485 if (ds->vl[i + (w + 1) * j] != BELOW_DOT(state, i, j)) {
2490 if (ds->vl[i + (w + 1) * j] != BELOW_DOT(state, i, j) ||
2494 BORDER + i * TILE_SIZE - LINEWIDTH/2,
2495 BORDER + j * TILE_SIZE + LINEWIDTH/2,
2496 LINEWIDTH, TILE_SIZE - LINEWIDTH,
2501 if (ds->vl[i + (w + 1) * j] != BELOW_DOT(state, i, j)) {
2504 BORDER + i * TILE_SIZE - CROSS_SIZE,
2505 BORDER + j * TILE_SIZE + TILE_SIZE/2 - CROSS_SIZE,
2506 BORDER + i * TILE_SIZE + CROSS_SIZE - 1,
2507 BORDER + j * TILE_SIZE + TILE_SIZE/2 + CROSS_SIZE - 1,
2510 BORDER + i * TILE_SIZE + CROSS_SIZE - 1,
2511 BORDER + j * TILE_SIZE + TILE_SIZE/2 - CROSS_SIZE,
2512 BORDER + i * TILE_SIZE - CROSS_SIZE,
2513 BORDER + j * TILE_SIZE + TILE_SIZE/2 + CROSS_SIZE - 1,
2518 ds->vl[i + (w + 1) * j] = BELOW_DOT(state, i, j);
2522 /* Horizontal lines */
2523 for (j = 0; j < h + 1; ++j) {
2524 for (i = 0; i < w; ++i) {
2525 switch (RIGHTOF_DOT(state, i, j)) {
2527 if (ds->hl[i + w * j] != RIGHTOF_DOT(state, i, j)) {
2532 if (ds->hl[i + w * j] != RIGHTOF_DOT(state, i, j) ||
2536 BORDER + i * TILE_SIZE + LINEWIDTH/2,
2537 BORDER + j * TILE_SIZE - LINEWIDTH/2,
2538 TILE_SIZE - LINEWIDTH, LINEWIDTH,
2543 if (ds->hl[i + w * j] != RIGHTOF_DOT(state, i, j)) {
2546 BORDER + i * TILE_SIZE + TILE_SIZE/2 - CROSS_SIZE,
2547 BORDER + j * TILE_SIZE + CROSS_SIZE - 1,
2548 BORDER + i * TILE_SIZE + TILE_SIZE/2 + CROSS_SIZE - 1,
2549 BORDER + j * TILE_SIZE - CROSS_SIZE,
2552 BORDER + i * TILE_SIZE + TILE_SIZE/2 - CROSS_SIZE,
2553 BORDER + j * TILE_SIZE - CROSS_SIZE,
2554 BORDER + i * TILE_SIZE + TILE_SIZE/2 + CROSS_SIZE - 1,
2555 BORDER + j * TILE_SIZE + CROSS_SIZE - 1,
2560 ds->hl[i + w * j] = RIGHTOF_DOT(state, i, j);
2565 static float game_anim_length(game_state *oldstate, game_state *newstate,
2566 int dir, game_ui *ui)
2571 static float game_flash_length(game_state *oldstate, game_state *newstate,
2572 int dir, game_ui *ui)
2574 if (!oldstate->solved && newstate->solved &&
2575 !oldstate->cheated && !newstate->cheated) {
2582 static int game_wants_statusbar(void)
2587 static int game_timing_state(game_state *state, game_ui *ui)
2592 static void game_print_size(game_params *params, float *x, float *y)
2597 * I'll use 7mm squares by default.
2599 game_compute_size(params, 700, &pw, &ph);
2604 static void game_print(drawing *dr, game_state *state, int tilesize)
2606 int w = state->w, h = state->h;
2607 int ink = print_mono_colour(dr, 0);
2609 game_drawstate ads, *ds = &ads;
2610 ds->tilesize = tilesize;
2613 * Dots. I'll deliberately make the dots a bit wider than the
2614 * lines, so you can still see them. (And also because it's
2615 * annoyingly tricky to make them _exactly_ the same size...)
2617 for (y = 0; y <= h; y++)
2618 for (x = 0; x <= w; x++)
2619 draw_circle(dr, BORDER + x * TILE_SIZE, BORDER + y * TILE_SIZE,
2620 LINEWIDTH, ink, ink);
2625 for (y = 0; y < h; y++)
2626 for (x = 0; x < w; x++)
2627 if (CLUE_AT(state, x, y) != ' ') {
2630 c[0] = CLUE_AT(state, x, y);
2633 BORDER + x * TILE_SIZE + TILE_SIZE/2,
2634 BORDER + y * TILE_SIZE + TILE_SIZE/2,
2635 FONT_VARIABLE, TILE_SIZE/2,
2636 ALIGN_VCENTRE | ALIGN_HCENTRE, ink, c);
2640 * Lines. (At the moment, I'm not bothering with crosses.)
2642 for (y = 0; y <= h; y++)
2643 for (x = 0; x < w; x++)
2644 if (RIGHTOF_DOT(state, x, y) == LINE_YES)
2645 draw_rect(dr, BORDER + x * TILE_SIZE,
2646 BORDER + y * TILE_SIZE - LINEWIDTH/2,
2647 TILE_SIZE, (LINEWIDTH/2) * 2 + 1, ink);
2648 for (y = 0; y < h; y++)
2649 for (x = 0; x <= w; x++)
2650 if (BELOW_DOT(state, x, y) == LINE_YES)
2651 draw_rect(dr, BORDER + x * TILE_SIZE - LINEWIDTH/2,
2652 BORDER + y * TILE_SIZE,
2653 (LINEWIDTH/2) * 2 + 1, TILE_SIZE, ink);
2657 #define thegame loopy
2660 const struct game thegame = {
2661 "Loopy", "games.loopy",
2668 TRUE, game_configure, custom_params,
2676 TRUE, game_text_format,
2684 PREFERRED_TILE_SIZE, game_compute_size, game_set_size,
2687 game_free_drawstate,
2691 TRUE, FALSE, game_print_size, game_print,
2692 game_wants_statusbar,
2693 FALSE, game_timing_state,
2694 0, /* mouse_priorities */