-
Notifications
You must be signed in to change notification settings - Fork 0
/
netslide.c
1893 lines (1630 loc) · 55.3 KB
/
netslide.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*
* netslide.c: cross between Net and Sixteen, courtesy of Richard
* Boulton.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <ctype.h>
#include <math.h>
#include "puzzles.h"
#include "tree234.h"
#define MATMUL(xr,yr,m,x,y) do { \
float rx, ry, xx = (x), yy = (y), *mat = (m); \
rx = mat[0] * xx + mat[2] * yy; \
ry = mat[1] * xx + mat[3] * yy; \
(xr) = rx; (yr) = ry; \
} while (0)
/* Direction and other bitfields */
#define R 0x01
#define U 0x02
#define L 0x04
#define D 0x08
#define FLASHING 0x10
#define ACTIVE 0x20
/* Corner flags go in the barriers array */
#define RU 0x10
#define UL 0x20
#define LD 0x40
#define DR 0x80
/* Get tile at given coordinate */
#define T(state, x, y) ( (y) * (state)->width + (x) )
/* Rotations: Anticlockwise, Clockwise, Flip, general rotate */
#define A(x) ( (((x) & 0x07) << 1) | (((x) & 0x08) >> 3) )
#define C(x) ( (((x) & 0x0E) >> 1) | (((x) & 0x01) << 3) )
#define F(x) ( (((x) & 0x0C) >> 2) | (((x) & 0x03) << 2) )
#define ROT(x, n) ( ((n)&3) == 0 ? (x) : \
((n)&3) == 1 ? A(x) : \
((n)&3) == 2 ? F(x) : C(x) )
/* X and Y displacements */
#define X(x) ( (x) == R ? +1 : (x) == L ? -1 : 0 )
#define Y(x) ( (x) == D ? +1 : (x) == U ? -1 : 0 )
/* Bit count */
#define COUNT(x) ( (((x) & 0x08) >> 3) + (((x) & 0x04) >> 2) + \
(((x) & 0x02) >> 1) + ((x) & 0x01) )
#define PREFERRED_TILE_SIZE 48
#define TILE_SIZE (ds->tilesize)
#define BORDER TILE_SIZE
#define TILE_BORDER 1
#define WINDOW_OFFSET 0
#define ANIM_TIME 0.13F
#define FLASH_FRAME 0.07F
enum {
COL_BACKGROUND,
COL_FLASHING,
COL_BORDER,
COL_WIRE,
COL_ENDPOINT,
COL_POWERED,
COL_BARRIER,
COL_LOWLIGHT,
COL_TEXT,
NCOLOURS
};
struct game_params {
int width;
int height;
int wrapping;
float barrier_probability;
int movetarget;
};
struct game_state {
int width, height, cx, cy, wrapping, completed;
int used_solve;
int move_count, movetarget;
/* position (row or col number, starting at 0) of last move. */
int last_move_row, last_move_col;
/* direction of last move: +1 or -1 */
int last_move_dir;
unsigned char *tiles;
unsigned char *barriers;
};
#define OFFSET(x2,y2,x1,y1,dir,state) \
( (x2) = ((x1) + (state)->width + X((dir))) % (state)->width, \
(y2) = ((y1) + (state)->height + Y((dir))) % (state)->height)
#define index(state, a, x, y) ( a[(y) * (state)->width + (x)] )
#define tile(state, x, y) index(state, (state)->tiles, x, y)
#define barrier(state, x, y) index(state, (state)->barriers, x, y)
struct xyd {
int x, y, direction;
};
static int xyd_cmp(void *av, void *bv) {
struct xyd *a = (struct xyd *)av;
struct xyd *b = (struct xyd *)bv;
if (a->x < b->x)
return -1;
if (a->x > b->x)
return +1;
if (a->y < b->y)
return -1;
if (a->y > b->y)
return +1;
if (a->direction < b->direction)
return -1;
if (a->direction > b->direction)
return +1;
return 0;
}
static struct xyd *new_xyd(int x, int y, int direction)
{
struct xyd *xyd = snew(struct xyd);
xyd->x = x;
xyd->y = y;
xyd->direction = direction;
return xyd;
}
static void slide_col(game_state *state, int dir, int col);
static void slide_col_int(int w, int h, unsigned char *tiles, int dir, int col);
static void slide_row(game_state *state, int dir, int row);
static void slide_row_int(int w, int h, unsigned char *tiles, int dir, int row);
/* ----------------------------------------------------------------------
* Manage game parameters.
*/
static game_params *default_params(void)
{
game_params *ret = snew(game_params);
ret->width = 3;
ret->height = 3;
ret->wrapping = FALSE;
ret->barrier_probability = 1.0;
ret->movetarget = 0;
return ret;
}
static const struct { int x, y, wrap, bprob; const char* desc; }
netslide_presets[] = {
{3, 3, FALSE, 1, " easy"},
{3, 3, FALSE, 0, " medium"},
{3, 3, TRUE, 0, " hard"},
{4, 4, FALSE, 1, " easy"},
{4, 4, FALSE, 0, " medium"},
{4, 4, TRUE, 0, " hard"},
{5, 5, FALSE, 1, " easy"},
{5, 5, FALSE, 0, " medium"},
{5, 5, TRUE, 0, " hard"},
};
static int game_fetch_preset(int i, char **name, game_params **params)
{
game_params *ret;
char str[80];
if (i < 0 || i >= lenof(netslide_presets))
return FALSE;
ret = snew(game_params);
ret->width = netslide_presets[i].x;
ret->height = netslide_presets[i].y;
ret->wrapping = netslide_presets[i].wrap;
ret->barrier_probability = (float)netslide_presets[i].bprob;
ret->movetarget = 0;
sprintf(str, "%dx%d%s", ret->width, ret->height, netslide_presets[i].desc);
*name = dupstr(str);
*params = ret;
return TRUE;
}
static void free_params(game_params *params)
{
sfree(params);
}
static game_params *dup_params(const game_params *params)
{
game_params *ret = snew(game_params);
*ret = *params; /* structure copy */
return ret;
}
static void decode_params(game_params *ret, char const *string)
{
char const *p = string;
ret->wrapping = FALSE;
ret->barrier_probability = 0.0;
ret->movetarget = 0;
ret->width = atoi(p);
while (*p && isdigit((unsigned char)*p)) p++;
if (*p == 'x') {
p++;
ret->height = atoi(p);
while (*p && isdigit((unsigned char)*p)) p++;
if ( (ret->wrapping = (*p == 'w')) != 0 )
p++;
if (*p == 'b') {
ret->barrier_probability = (float)atof(++p);
while (*p && (isdigit((unsigned char)*p) || *p == '.')) p++;
}
if (*p == 'm') {
ret->movetarget = atoi(++p);
}
} else {
ret->height = ret->width;
}
}
static char *encode_params(const game_params *params, int full)
{
char ret[400];
int len;
len = sprintf(ret, "%dx%d", params->width, params->height);
if (params->wrapping)
ret[len++] = 'w';
if (full && params->barrier_probability)
len += sprintf(ret+len, "b%g", params->barrier_probability);
/* Shuffle limit is part of the limited parameters, because we have to
* provide the target move count. */
if (params->movetarget)
len += sprintf(ret+len, "m%d", params->movetarget);
assert(len < lenof(ret));
ret[len] = '\0';
return dupstr(ret);
}
static config_item *game_configure(const game_params *params)
{
config_item *ret;
char buf[80];
ret = snewn(6, config_item);
ret[0].name = "Width";
ret[0].type = C_STRING;
sprintf(buf, "%d", params->width);
ret[0].sval = dupstr(buf);
ret[0].ival = 0;
ret[1].name = "Height";
ret[1].type = C_STRING;
sprintf(buf, "%d", params->height);
ret[1].sval = dupstr(buf);
ret[1].ival = 0;
ret[2].name = "Walls wrap around";
ret[2].type = C_BOOLEAN;
ret[2].sval = NULL;
ret[2].ival = params->wrapping;
ret[3].name = "Barrier probability";
ret[3].type = C_STRING;
sprintf(buf, "%g", params->barrier_probability);
ret[3].sval = dupstr(buf);
ret[3].ival = 0;
ret[4].name = "Number of shuffling moves";
ret[4].type = C_STRING;
sprintf(buf, "%d", params->movetarget);
ret[4].sval = dupstr(buf);
ret[4].ival = 0;
ret[5].name = NULL;
ret[5].type = C_END;
ret[5].sval = NULL;
ret[5].ival = 0;
return ret;
}
static game_params *custom_params(const config_item *cfg)
{
game_params *ret = snew(game_params);
ret->width = atoi(cfg[0].sval);
ret->height = atoi(cfg[1].sval);
ret->wrapping = cfg[2].ival;
ret->barrier_probability = (float)atof(cfg[3].sval);
ret->movetarget = atoi(cfg[4].sval);
return ret;
}
static char *validate_params(const game_params *params, int full)
{
if (params->width <= 1 || params->height <= 1)
return "Width and height must both be greater than one";
if (params->barrier_probability < 0)
return "Barrier probability may not be negative";
if (params->barrier_probability > 1)
return "Barrier probability may not be greater than 1";
return NULL;
}
/* ----------------------------------------------------------------------
* Randomly select a new game description.
*/
static char *new_game_desc(const game_params *params, random_state *rs,
char **aux, int interactive)
{
tree234 *possibilities, *barriertree;
int w, h, x, y, cx, cy, nbarriers;
unsigned char *tiles, *barriers;
char *desc, *p;
w = params->width;
h = params->height;
tiles = snewn(w * h, unsigned char);
memset(tiles, 0, w * h);
barriers = snewn(w * h, unsigned char);
memset(barriers, 0, w * h);
cx = w / 2;
cy = h / 2;
/*
* Construct the unshuffled grid.
*
* To do this, we simply start at the centre point, repeatedly
* choose a random possibility out of the available ways to
* extend a used square into an unused one, and do it. After
* extending the third line out of a square, we remove the
* fourth from the possibilities list to avoid any full-cross
* squares (which would make the game too easy because they
* only have one orientation).
*
* The slightly worrying thing is the avoidance of full-cross
* squares. Can this cause our unsophisticated construction
* algorithm to paint itself into a corner, by getting into a
* situation where there are some unreached squares and the
* only way to reach any of them is to extend a T-piece into a
* full cross?
*
* Answer: no it can't, and here's a proof.
*
* Any contiguous group of such unreachable squares must be
* surrounded on _all_ sides by T-pieces pointing away from the
* group. (If not, then there is a square which can be extended
* into one of the `unreachable' ones, and so it wasn't
* unreachable after all.) In particular, this implies that
* each contiguous group of unreachable squares must be
* rectangular in shape (any deviation from that yields a
* non-T-piece next to an `unreachable' square).
*
* So we have a rectangle of unreachable squares, with T-pieces
* forming a solid border around the rectangle. The corners of
* that border must be connected (since every tile connects all
* the lines arriving in it), and therefore the border must
* form a closed loop around the rectangle.
*
* But this can't have happened in the first place, since we
* _know_ we've avoided creating closed loops! Hence, no such
* situation can ever arise, and the naive grid construction
* algorithm will guaranteeably result in a complete grid
* containing no unreached squares, no full crosses _and_ no
* closed loops. []
*/
possibilities = newtree234(xyd_cmp);
if (cx+1 < w)
add234(possibilities, new_xyd(cx, cy, R));
if (cy-1 >= 0)
add234(possibilities, new_xyd(cx, cy, U));
if (cx-1 >= 0)
add234(possibilities, new_xyd(cx, cy, L));
if (cy+1 < h)
add234(possibilities, new_xyd(cx, cy, D));
while (count234(possibilities) > 0) {
int i;
struct xyd *xyd;
int x1, y1, d1, x2, y2, d2, d;
/*
* Extract a randomly chosen possibility from the list.
*/
i = random_upto(rs, count234(possibilities));
xyd = delpos234(possibilities, i);
x1 = xyd->x;
y1 = xyd->y;
d1 = xyd->direction;
sfree(xyd);
OFFSET(x2, y2, x1, y1, d1, params);
d2 = F(d1);
#ifdef GENERATION_DIAGNOSTICS
printf("picked (%d,%d,%c) <-> (%d,%d,%c)\n",
x1, y1, "0RU3L567D9abcdef"[d1], x2, y2, "0RU3L567D9abcdef"[d2]);
#endif
/*
* Make the connection. (We should be moving to an as yet
* unused tile.)
*/
index(params, tiles, x1, y1) |= d1;
assert(index(params, tiles, x2, y2) == 0);
index(params, tiles, x2, y2) |= d2;
/*
* If we have created a T-piece, remove its last
* possibility.
*/
if (COUNT(index(params, tiles, x1, y1)) == 3) {
struct xyd xyd1, *xydp;
xyd1.x = x1;
xyd1.y = y1;
xyd1.direction = 0x0F ^ index(params, tiles, x1, y1);
xydp = find234(possibilities, &xyd1, NULL);
if (xydp) {
#ifdef GENERATION_DIAGNOSTICS
printf("T-piece; removing (%d,%d,%c)\n",
xydp->x, xydp->y, "0RU3L567D9abcdef"[xydp->direction]);
#endif
del234(possibilities, xydp);
sfree(xydp);
}
}
/*
* Remove all other possibilities that were pointing at the
* tile we've just moved into.
*/
for (d = 1; d < 0x10; d <<= 1) {
int x3, y3, d3;
struct xyd xyd1, *xydp;
OFFSET(x3, y3, x2, y2, d, params);
d3 = F(d);
xyd1.x = x3;
xyd1.y = y3;
xyd1.direction = d3;
xydp = find234(possibilities, &xyd1, NULL);
if (xydp) {
#ifdef GENERATION_DIAGNOSTICS
printf("Loop avoidance; removing (%d,%d,%c)\n",
xydp->x, xydp->y, "0RU3L567D9abcdef"[xydp->direction]);
#endif
del234(possibilities, xydp);
sfree(xydp);
}
}
/*
* Add new possibilities to the list for moving _out_ of
* the tile we have just moved into.
*/
for (d = 1; d < 0x10; d <<= 1) {
int x3, y3;
if (d == d2)
continue; /* we've got this one already */
if (!params->wrapping) {
if (d == U && y2 == 0)
continue;
if (d == D && y2 == h-1)
continue;
if (d == L && x2 == 0)
continue;
if (d == R && x2 == w-1)
continue;
}
OFFSET(x3, y3, x2, y2, d, params);
if (index(params, tiles, x3, y3))
continue; /* this would create a loop */
#ifdef GENERATION_DIAGNOSTICS
printf("New frontier; adding (%d,%d,%c)\n",
x2, y2, "0RU3L567D9abcdef"[d]);
#endif
add234(possibilities, new_xyd(x2, y2, d));
}
}
/* Having done that, we should have no possibilities remaining. */
assert(count234(possibilities) == 0);
freetree234(possibilities);
/*
* Now compute a list of the possible barrier locations.
*/
barriertree = newtree234(xyd_cmp);
for (y = 0; y < h; y++) {
for (x = 0; x < w; x++) {
if (!(index(params, tiles, x, y) & R) &&
(params->wrapping || x < w-1))
add234(barriertree, new_xyd(x, y, R));
if (!(index(params, tiles, x, y) & D) &&
(params->wrapping || y < h-1))
add234(barriertree, new_xyd(x, y, D));
}
}
/*
* Save the unshuffled grid in aux.
*/
{
char *solution;
int i;
/*
* String format is exactly the same as a solve move, so we
* can just dupstr this in solve_game().
*/
solution = snewn(w * h + 2, char);
solution[0] = 'S';
for (i = 0; i < w * h; i++)
solution[i+1] = "0123456789abcdef"[tiles[i] & 0xF];
solution[w*h+1] = '\0';
*aux = solution;
}
/*
* Now shuffle the grid.
* FIXME - this simply does a set of random moves to shuffle the pieces,
* although we make a token effort to avoid boring cases by avoiding moves
* that directly undo the previous one, or that repeat so often as to
* turn into fewer moves.
*
* A better way would be to number all the pieces, generate a placement
* for all the numbers as for "sixteen", observing parity constraints if
* neccessary, and then place the pieces according to their numbering.
* BUT - I'm not sure if this will work, since we disallow movement of
* the middle row and column.
*/
{
int i;
int cols = w - 1;
int rows = h - 1;
int moves = params->movetarget;
int prevdir = -1, prevrowcol = -1, nrepeats = 0;
if (!moves) moves = cols * rows * 2;
for (i = 0; i < moves; /* incremented conditionally */) {
/* Choose a direction: 0,1,2,3 = up, right, down, left. */
int dir = random_upto(rs, 4);
int rowcol;
if (dir % 2 == 0) {
int col = random_upto(rs, cols);
if (col >= cx) col += 1; /* avoid centre */
if (col == prevrowcol) {
if (dir == 2-prevdir)
continue; /* undoes last move */
else if (dir == prevdir && (nrepeats+1)*2 > h)
continue; /* makes fewer moves */
}
slide_col_int(w, h, tiles, 1 - dir, col);
rowcol = col;
} else {
int row = random_upto(rs, rows);
if (row >= cy) row += 1; /* avoid centre */
if (row == prevrowcol) {
if (dir == 4-prevdir)
continue; /* undoes last move */
else if (dir == prevdir && (nrepeats+1)*2 > w)
continue; /* makes fewer moves */
}
slide_row_int(w, h, tiles, 2 - dir, row);
rowcol = row;
}
if (dir == prevdir && rowcol == prevrowcol)
nrepeats++;
else
nrepeats = 1;
prevdir = dir;
prevrowcol = rowcol;
i++; /* if we got here, the move was accepted */
}
}
/*
* And now choose barrier locations. (We carefully do this
* _after_ shuffling, so that changing the barrier rate in the
* params while keeping the random seed the same will give the
* same shuffled grid and _only_ change the barrier locations.
* Also the way we choose barrier locations, by repeatedly
* choosing one possibility from the list until we have enough,
* is designed to ensure that raising the barrier rate while
* keeping the seed the same will provide a superset of the
* previous barrier set - i.e. if you ask for 10 barriers, and
* then decide that's still too hard and ask for 20, you'll get
* the original 10 plus 10 more, rather than getting 20 new
* ones and the chance of remembering your first 10.)
*/
nbarriers = (int)(params->barrier_probability * count234(barriertree));
assert(nbarriers >= 0 && nbarriers <= count234(barriertree));
while (nbarriers > 0) {
int i;
struct xyd *xyd;
int x1, y1, d1, x2, y2, d2;
/*
* Extract a randomly chosen barrier from the list.
*/
i = random_upto(rs, count234(barriertree));
xyd = delpos234(barriertree, i);
assert(xyd != NULL);
x1 = xyd->x;
y1 = xyd->y;
d1 = xyd->direction;
sfree(xyd);
OFFSET(x2, y2, x1, y1, d1, params);
d2 = F(d1);
index(params, barriers, x1, y1) |= d1;
index(params, barriers, x2, y2) |= d2;
nbarriers--;
}
/*
* Clean up the rest of the barrier list.
*/
{
struct xyd *xyd;
while ( (xyd = delpos234(barriertree, 0)) != NULL)
sfree(xyd);
freetree234(barriertree);
}
/*
* Finally, encode the grid into a string game description.
*
* My syntax is extremely simple: each square is encoded as a
* hex digit in which bit 0 means a connection on the right,
* bit 1 means up, bit 2 left and bit 3 down. (i.e. the same
* encoding as used internally). Each digit is followed by
* optional barrier indicators: `v' means a vertical barrier to
* the right of it, and `h' means a horizontal barrier below
* it.
*/
desc = snewn(w * h * 3 + 1, char);
p = desc;
for (y = 0; y < h; y++) {
for (x = 0; x < w; x++) {
*p++ = "0123456789abcdef"[index(params, tiles, x, y)];
if ((params->wrapping || x < w-1) &&
(index(params, barriers, x, y) & R))
*p++ = 'v';
if ((params->wrapping || y < h-1) &&
(index(params, barriers, x, y) & D))
*p++ = 'h';
}
}
assert(p - desc <= w*h*3);
*p = '\0';
sfree(tiles);
sfree(barriers);
return desc;
}
static char *validate_desc(const game_params *params, const char *desc)
{
int w = params->width, h = params->height;
int i;
for (i = 0; i < w*h; i++) {
if (*desc >= '0' && *desc <= '9')
/* OK */;
else if (*desc >= 'a' && *desc <= 'f')
/* OK */;
else if (*desc >= 'A' && *desc <= 'F')
/* OK */;
else if (!*desc)
return "Game description shorter than expected";
else
return "Game description contained unexpected character";
desc++;
while (*desc == 'h' || *desc == 'v')
desc++;
}
if (*desc)
return "Game description longer than expected";
return NULL;
}
/* ----------------------------------------------------------------------
* Construct an initial game state, given a description and parameters.
*/
static game_state *new_game(midend *me, const game_params *params,
const char *desc)
{
game_state *state;
int w, h, x, y;
assert(params->width > 0 && params->height > 0);
assert(params->width > 1 || params->height > 1);
/*
* Create a blank game state.
*/
state = snew(game_state);
w = state->width = params->width;
h = state->height = params->height;
state->cx = state->width / 2;
state->cy = state->height / 2;
state->wrapping = params->wrapping;
state->movetarget = params->movetarget;
state->completed = 0;
state->used_solve = FALSE;
state->move_count = 0;
state->last_move_row = -1;
state->last_move_col = -1;
state->last_move_dir = 0;
state->tiles = snewn(state->width * state->height, unsigned char);
memset(state->tiles, 0, state->width * state->height);
state->barriers = snewn(state->width * state->height, unsigned char);
memset(state->barriers, 0, state->width * state->height);
/*
* Parse the game description into the grid.
*/
for (y = 0; y < h; y++) {
for (x = 0; x < w; x++) {
if (*desc >= '0' && *desc <= '9')
tile(state, x, y) = *desc - '0';
else if (*desc >= 'a' && *desc <= 'f')
tile(state, x, y) = *desc - 'a' + 10;
else if (*desc >= 'A' && *desc <= 'F')
tile(state, x, y) = *desc - 'A' + 10;
if (*desc)
desc++;
while (*desc == 'h' || *desc == 'v') {
int x2, y2, d1, d2;
if (*desc == 'v')
d1 = R;
else
d1 = D;
OFFSET(x2, y2, x, y, d1, state);
d2 = F(d1);
barrier(state, x, y) |= d1;
barrier(state, x2, y2) |= d2;
desc++;
}
}
}
/*
* Set up border barriers if this is a non-wrapping game.
*/
if (!state->wrapping) {
for (x = 0; x < state->width; x++) {
barrier(state, x, 0) |= U;
barrier(state, x, state->height-1) |= D;
}
for (y = 0; y < state->height; y++) {
barrier(state, 0, y) |= L;
barrier(state, state->width-1, y) |= R;
}
}
/*
* Set up the barrier corner flags, for drawing barriers
* prettily when they meet.
*/
for (y = 0; y < state->height; y++) {
for (x = 0; x < state->width; x++) {
int dir;
for (dir = 1; dir < 0x10; dir <<= 1) {
int dir2 = A(dir);
int x1, y1, x2, y2, x3, y3;
int corner = FALSE;
if (!(barrier(state, x, y) & dir))
continue;
if (barrier(state, x, y) & dir2)
corner = TRUE;
x1 = x + X(dir), y1 = y + Y(dir);
if (x1 >= 0 && x1 < state->width &&
y1 >= 0 && y1 < state->height &&
(barrier(state, x1, y1) & dir2))
corner = TRUE;
x2 = x + X(dir2), y2 = y + Y(dir2);
if (x2 >= 0 && x2 < state->width &&
y2 >= 0 && y2 < state->height &&
(barrier(state, x2, y2) & dir))
corner = TRUE;
if (corner) {
barrier(state, x, y) |= (dir << 4);
if (x1 >= 0 && x1 < state->width &&
y1 >= 0 && y1 < state->height)
barrier(state, x1, y1) |= (A(dir) << 4);
if (x2 >= 0 && x2 < state->width &&
y2 >= 0 && y2 < state->height)
barrier(state, x2, y2) |= (C(dir) << 4);
x3 = x + X(dir) + X(dir2), y3 = y + Y(dir) + Y(dir2);
if (x3 >= 0 && x3 < state->width &&
y3 >= 0 && y3 < state->height)
barrier(state, x3, y3) |= (F(dir) << 4);
}
}
}
}
return state;
}
static game_state *dup_game(const game_state *state)
{
game_state *ret;
ret = snew(game_state);
ret->width = state->width;
ret->height = state->height;
ret->cx = state->cx;
ret->cy = state->cy;
ret->wrapping = state->wrapping;
ret->movetarget = state->movetarget;
ret->completed = state->completed;
ret->used_solve = state->used_solve;
ret->move_count = state->move_count;
ret->last_move_row = state->last_move_row;
ret->last_move_col = state->last_move_col;
ret->last_move_dir = state->last_move_dir;
ret->tiles = snewn(state->width * state->height, unsigned char);
memcpy(ret->tiles, state->tiles, state->width * state->height);
ret->barriers = snewn(state->width * state->height, unsigned char);
memcpy(ret->barriers, state->barriers, state->width * state->height);
return ret;
}
static void free_game(game_state *state)
{
sfree(state->tiles);
sfree(state->barriers);
sfree(state);
}
static char *solve_game(const game_state *state, const game_state *currstate,
const char *aux, char **error)
{
if (!aux) {
*error = "Solution not known for this puzzle";
return NULL;
}
return dupstr(aux);
}
static int game_can_format_as_text_now(const game_params *params)
{
return TRUE;
}
static char *game_text_format(const game_state *state)
{
return NULL;
}
/* ----------------------------------------------------------------------
* Utility routine.
*/
/*
* Compute which squares are reachable from the centre square, as a
* quick visual aid to determining how close the game is to
* completion. This is also a simple way to tell if the game _is_
* completed - just call this function and see whether every square
* is marked active.
*
* squares in the moving_row and moving_col are always inactive - this
* is so that "current" doesn't appear to jump across moving lines.
*/
static unsigned char *compute_active(const game_state *state,
int moving_row, int moving_col)
{
unsigned char *active;
tree234 *todo;
struct xyd *xyd;
active = snewn(state->width * state->height, unsigned char);
memset(active, 0, state->width * state->height);
/*
* We only store (x,y) pairs in todo, but it's easier to reuse
* xyd_cmp and just store direction 0 every time.
*/
todo = newtree234(xyd_cmp);
index(state, active, state->cx, state->cy) = ACTIVE;
add234(todo, new_xyd(state->cx, state->cy, 0));
while ( (xyd = delpos234(todo, 0)) != NULL) {
int x1, y1, d1, x2, y2, d2;
x1 = xyd->x;
y1 = xyd->y;
sfree(xyd);
for (d1 = 1; d1 < 0x10; d1 <<= 1) {
OFFSET(x2, y2, x1, y1, d1, state);
d2 = F(d1);
/*
* If the next tile in this direction is connected to
* us, and there isn't a barrier in the way, and it
* isn't already marked active, then mark it active and
* add it to the to-examine list.
*/
if ((x2 != moving_col && y2 != moving_row) &&
(tile(state, x1, y1) & d1) &&
(tile(state, x2, y2) & d2) &&
!(barrier(state, x1, y1) & d1) &&
!index(state, active, x2, y2)) {
index(state, active, x2, y2) = ACTIVE;
add234(todo, new_xyd(x2, y2, 0));
}
}
}
/* Now we expect the todo list to have shrunk to zero size. */
assert(count234(todo) == 0);
freetree234(todo);
return active;
}
struct game_ui {
int cur_x, cur_y;
int cur_visible;
};
static game_ui *new_ui(const game_state *state)
{
game_ui *ui = snew(game_ui);
ui->cur_x = 0;
ui->cur_y = -1;
ui->cur_visible = FALSE;
return ui;
}
static void free_ui(game_ui *ui)
{
sfree(ui);
}
static char *encode_ui(const game_ui *ui)
{
return NULL;
}
static void decode_ui(game_ui *ui, const char *encoding)