15 #define MATMUL(xr,yr,m,x,y) do { \
16 float rx, ry, xx = (x), yy = (y), *mat = (m); \
17 rx = mat[0] * xx + mat[2] * yy; \
18 ry = mat[1] * xx + mat[3] * yy; \
19 (xr) = rx; (yr) = ry; \
22 /* Direction and other bitfields */
30 /* Rotations: Anticlockwise, Clockwise, Flip, general rotate */
31 #define A(x) ( (((x) & 0x07) << 1) | (((x) & 0x08) >> 3) )
32 #define C(x) ( (((x) & 0x0E) >> 1) | (((x) & 0x01) << 3) )
33 #define F(x) ( (((x) & 0x0C) >> 2) | (((x) & 0x03) << 2) )
34 #define ROT(x, n) ( ((n)&3) == 0 ? (x) : \
35 ((n)&3) == 1 ? A(x) : \
36 ((n)&3) == 2 ? F(x) : C(x) )
38 /* X and Y displacements */
39 #define X(x) ( (x) == R ? +1 : (x) == L ? -1 : 0 )
40 #define Y(x) ( (x) == D ? +1 : (x) == U ? -1 : 0 )
43 #define COUNT(x) ( (((x) & 0x08) >> 3) + (((x) & 0x04) >> 2) + \
44 (((x) & 0x02) >> 1) + ((x) & 0x01) )
46 #define PREFERRED_TILE_SIZE 32
47 #define TILE_SIZE (ds->tilesize)
50 #define WINDOW_OFFSET 4
52 #define WINDOW_OFFSET 16
55 #define ROTATE_TIME 0.13F
56 #define FLASH_FRAME 0.07F
58 /* Transform physical coords to game coords using game_drawstate ds */
59 #define GX(x) (((x) + ds->org_x) % ds->width)
60 #define GY(y) (((y) + ds->org_y) % ds->height)
61 /* ...and game coords to physical coords */
62 #define RX(x) (((x) + ds->width - ds->org_x) % ds->width)
63 #define RY(y) (((y) + ds->height - ds->org_y) % ds->height)
81 float barrier_probability
;
85 int width
, height
, wrapping
, completed
;
86 int last_rotate_x
, last_rotate_y
, last_rotate_dir
;
89 unsigned char *barriers
;
92 #define OFFSETWH(x2,y2,x1,y1,dir,width,height) \
93 ( (x2) = ((x1) + width + X((dir))) % width, \
94 (y2) = ((y1) + height + Y((dir))) % height)
96 #define OFFSET(x2,y2,x1,y1,dir,state) \
97 OFFSETWH(x2,y2,x1,y1,dir,(state)->width,(state)->height)
99 #define index(state, a, x, y) ( a[(y) * (state)->width + (x)] )
100 #define tile(state, x, y) index(state, (state)->tiles, x, y)
101 #define barrier(state, x, y) index(state, (state)->barriers, x, y)
107 static int xyd_cmp(const void *av
, const void *bv
) {
108 const struct xyd
*a
= (const struct xyd
*)av
;
109 const struct xyd
*b
= (const struct xyd
*)bv
;
118 if (a
->direction
< b
->direction
)
120 if (a
->direction
> b
->direction
)
125 static int xyd_cmp_nc(void *av
, void *bv
) { return xyd_cmp(av
, bv
); }
127 static struct xyd
*new_xyd(int x
, int y
, int direction
)
129 struct xyd
*xyd
= snew(struct xyd
);
132 xyd
->direction
= direction
;
136 /* ----------------------------------------------------------------------
137 * Manage game parameters.
139 static game_params
*default_params(void)
141 game_params
*ret
= snew(game_params
);
145 ret
->wrapping
= FALSE
;
147 ret
->barrier_probability
= 0.0;
152 static const struct game_params net_presets
[] = {
153 {5, 5, FALSE
, TRUE
, 0.0},
154 {7, 7, FALSE
, TRUE
, 0.0},
155 {9, 9, FALSE
, TRUE
, 0.0},
156 {11, 11, FALSE
, TRUE
, 0.0},
158 {13, 11, FALSE
, TRUE
, 0.0},
160 {5, 5, TRUE
, TRUE
, 0.0},
161 {7, 7, TRUE
, TRUE
, 0.0},
162 {9, 9, TRUE
, TRUE
, 0.0},
163 {11, 11, TRUE
, TRUE
, 0.0},
165 {13, 11, TRUE
, TRUE
, 0.0},
169 static int game_fetch_preset(int i
, char **name
, game_params
**params
)
174 if (i
< 0 || i
>= lenof(net_presets
))
177 ret
= snew(game_params
);
178 *ret
= net_presets
[i
];
180 sprintf(str
, "%dx%d%s", ret
->width
, ret
->height
,
181 ret
->wrapping ?
" wrapping" : "");
188 static void free_params(game_params
*params
)
193 static game_params
*dup_params(game_params
*params
)
195 game_params
*ret
= snew(game_params
);
196 *ret
= *params
; /* structure copy */
200 static void decode_params(game_params
*ret
, char const *string
)
202 char const *p
= string
;
204 ret
->width
= atoi(p
);
205 while (*p
&& isdigit((unsigned char)*p
)) p
++;
208 ret
->height
= atoi(p
);
209 while (*p
&& isdigit((unsigned char)*p
)) p
++;
211 ret
->height
= ret
->width
;
217 ret
->wrapping
= TRUE
;
218 } else if (*p
== 'b') {
220 ret
->barrier_probability
= atof(p
);
221 while (*p
&& (*p
== '.' || isdigit((unsigned char)*p
))) p
++;
222 } else if (*p
== 'a') {
226 p
++; /* skip any other gunk */
230 static char *encode_params(game_params
*params
, int full
)
235 len
= sprintf(ret
, "%dx%d", params
->width
, params
->height
);
236 if (params
->wrapping
)
238 if (full
&& params
->barrier_probability
)
239 len
+= sprintf(ret
+len
, "b%g", params
->barrier_probability
);
240 if (full
&& !params
->unique
)
242 assert(len
< lenof(ret
));
248 static config_item
*game_configure(game_params
*params
)
253 ret
= snewn(6, config_item
);
255 ret
[0].name
= "Width";
256 ret
[0].type
= C_STRING
;
257 sprintf(buf
, "%d", params
->width
);
258 ret
[0].sval
= dupstr(buf
);
261 ret
[1].name
= "Height";
262 ret
[1].type
= C_STRING
;
263 sprintf(buf
, "%d", params
->height
);
264 ret
[1].sval
= dupstr(buf
);
267 ret
[2].name
= "Walls wrap around";
268 ret
[2].type
= C_BOOLEAN
;
270 ret
[2].ival
= params
->wrapping
;
272 ret
[3].name
= "Barrier probability";
273 ret
[3].type
= C_STRING
;
274 sprintf(buf
, "%g", params
->barrier_probability
);
275 ret
[3].sval
= dupstr(buf
);
278 ret
[4].name
= "Ensure unique solution";
279 ret
[4].type
= C_BOOLEAN
;
281 ret
[4].ival
= params
->unique
;
291 static game_params
*custom_params(config_item
*cfg
)
293 game_params
*ret
= snew(game_params
);
295 ret
->width
= atoi(cfg
[0].sval
);
296 ret
->height
= atoi(cfg
[1].sval
);
297 ret
->wrapping
= cfg
[2].ival
;
298 ret
->barrier_probability
= (float)atof(cfg
[3].sval
);
299 ret
->unique
= cfg
[4].ival
;
304 static char *validate_params(game_params
*params
, int full
)
306 if (params
->width
<= 0 || params
->height
<= 0)
307 return "Width and height must both be greater than zero";
308 if (params
->width
<= 1 && params
->height
<= 1)
309 return "At least one of width and height must be greater than one";
310 if (params
->barrier_probability
< 0)
311 return "Barrier probability may not be negative";
312 if (params
->barrier_probability
> 1)
313 return "Barrier probability may not be greater than 1";
316 * Specifying either grid dimension as 2 in a wrapping puzzle
317 * makes it actually impossible to ensure a unique puzzle
322 * Without loss of generality, let us assume the puzzle _width_
323 * is 2, so we can conveniently discuss rows without having to
324 * say `rows/columns' all the time. (The height may be 2 as
325 * well, but that doesn't matter.)
327 * In each row, there are two edges between tiles: the inner
328 * edge (running down the centre of the grid) and the outer
329 * edge (the identified left and right edges of the grid).
331 * Lemma: In any valid 2xn puzzle there must be at least one
332 * row in which _exactly one_ of the inner edge and outer edge
335 * Proof: No row can have _both_ inner and outer edges
336 * connected, because this would yield a loop. So the only
337 * other way to falsify the lemma is for every row to have
338 * _neither_ the inner nor outer edge connected. But this
339 * means there is no connection at all between the left and
340 * right columns of the puzzle, so there are two disjoint
341 * subgraphs, which is also disallowed. []
343 * Given such a row, it is always possible to make the
344 * disconnected edge connected and the connected edge
345 * disconnected without changing the state of any other edge.
346 * (This is easily seen by case analysis on the various tiles:
347 * left-pointing and right-pointing endpoints can be exchanged,
348 * likewise T-pieces, and a corner piece can select its
349 * horizontal connectivity independently of its vertical.) This
350 * yields a distinct valid solution.
352 * Thus, for _every_ row in which exactly one of the inner and
353 * outer edge is connected, there are two valid states for that
354 * row, and hence the total number of solutions of the puzzle
355 * is at least 2^(number of such rows), and in particular is at
356 * least 2 since there must be at least one such row. []
358 if (full
&& params
->unique
&& params
->wrapping
&&
359 (params
->width
== 2 || params
->height
== 2))
360 return "No wrapping puzzle with a width or height of 2 can have"
361 " a unique solution";
366 /* ----------------------------------------------------------------------
367 * Solver used to assure solution uniqueness during generation.
371 * Test cases I used while debugging all this were
373 * ./net --generate 1 13x11w#12300
374 * which expands under the non-unique grid generation rules to
375 * 13x11w:5eaade1bd222664436d5e2965c12656b1129dd825219e3274d558d5eb2dab5da18898e571d5a2987be79746bd95726c597447d6da96188c513add829da7681da954db113d3cd244
376 * and has two ambiguous areas.
378 * An even better one is
379 * 13x11w#507896411361192
381 * 13x11w:b7125b1aec598eb31bd58d82572bc11494e5dee4e8db2bdd29b88d41a16bdd996d2996ddec8c83741a1e8674e78328ba71737b8894a9271b1cd1399453d1952e43951d9b712822e
382 * and has an ambiguous area _and_ a situation where loop avoidance
383 * is a necessary deductive technique.
386 * 48x25w#820543338195187
388 * 48x25w:255989d14cdd185deaa753a93821a12edc1ab97943ac127e2685d7b8b3c48861b2192416139212b316eddd35de43714ebc7628d753db32e596284d9ec52c5a7dc1b4c811a655117d16dc28921b2b4161352cab1d89d18bc836b8b891d55ea4622a1251861b5bc9a8aa3e5bcd745c95229ca6c3b5e21d5832d397e917325793d7eb442dc351b2db2a52ba8e1651642275842d8871d5534aabc6d5b741aaa2d48ed2a7dbbb3151ddb49d5b9a7ed1ab98ee75d613d656dbba347bc514c84556b43a9bc65a3256ead792488b862a9d2a8a39b4255a4949ed7dbd79443292521265896b4399c95ede89d7c8c797a6a57791a849adea489359a158aa12e5dacce862b8333b7ebea7d344d1a3c53198864b73a9dedde7b663abb1b539e1e8853b1b7edb14a2a17ebaae4dbe63598a2e7e9a2dbdad415bc1d8cb88cbab5a8c82925732cd282e641ea3bd7d2c6e776de9117a26be86deb7c82c89524b122cb9397cd1acd2284e744ea62b9279bae85479ababe315c3ac29c431333395b24e6a1e3c43a2da42d4dce84aadd5b154aea555eaddcbd6e527d228c19388d9b424d94214555a7edbdeebe569d4a56dc51a86bd9963e377bb74752bd5eaa5761ba545e297b62a1bda46ab4aee423ad6c661311783cc18786d4289236563cb4a75ec67d481c14814994464cd1b87396dee63e5ab6e952cc584baa1d4c47cb557ec84dbb63d487c8728118673a166846dd3a4ebc23d6cb9c5827d96b4556e91899db32b517eda815ae271a8911bd745447121dc8d321557bc2a435ebec1bbac35b1a291669451174e6aa2218a4a9c5a6ca31ebc45d84e3a82c121e9ced7d55e9a
389 * which has a spot (far right) where slightly more complex loop
390 * avoidance is required.
394 unsigned char *marked
;
400 static struct todo
*todo_new(int maxsize
)
402 struct todo
*todo
= snew(struct todo
);
403 todo
->marked
= snewn(maxsize
, unsigned char);
404 memset(todo
->marked
, 0, maxsize
);
405 todo
->buflen
= maxsize
+ 1;
406 todo
->buffer
= snewn(todo
->buflen
, int);
407 todo
->head
= todo
->tail
= 0;
411 static void todo_free(struct todo
*todo
)
418 static void todo_add(struct todo
*todo
, int index
)
420 if (todo
->marked
[index
])
421 return; /* already on the list */
422 todo
->marked
[index
] = TRUE
;
423 todo
->buffer
[todo
->tail
++] = index
;
424 if (todo
->tail
== todo
->buflen
)
428 static int todo_get(struct todo
*todo
) {
431 if (todo
->head
== todo
->tail
)
432 return -1; /* list is empty */
433 ret
= todo
->buffer
[todo
->head
++];
434 if (todo
->head
== todo
->buflen
)
436 todo
->marked
[ret
] = FALSE
;
441 static int net_solver(int w
, int h
, unsigned char *tiles
,
442 unsigned char *barriers
, int wrapping
)
444 unsigned char *tilestate
;
445 unsigned char *edgestate
;
454 * Set up the solver's data structures.
458 * tilestate stores the possible orientations of each tile.
459 * There are up to four of these, so we'll index the array in
460 * fours. tilestate[(y * w + x) * 4] and its three successive
461 * members give the possible orientations, clearing to 255 from
462 * the end as things are ruled out.
464 * In this loop we also count up the area of the grid (which is
465 * not _necessarily_ equal to w*h, because there might be one
466 * or more blank squares present. This will never happen in a
467 * grid generated _by_ this program, but it's worth keeping the
468 * solver as general as possible.)
470 tilestate
= snewn(w
* h
* 4, unsigned char);
472 for (i
= 0; i
< w
*h
; i
++) {
473 tilestate
[i
* 4] = tiles
[i
] & 0xF;
474 for (j
= 1; j
< 4; j
++) {
475 if (tilestate
[i
* 4 + j
- 1] == 255 ||
476 A(tilestate
[i
* 4 + j
- 1]) == tilestate
[i
* 4])
477 tilestate
[i
* 4 + j
] = 255;
479 tilestate
[i
* 4 + j
] = A(tilestate
[i
* 4 + j
- 1]);
486 * edgestate stores the known state of each edge. It is 0 for
487 * unknown, 1 for open (connected) and 2 for closed (not
490 * In principle we need only worry about each edge once each,
491 * but in fact it's easier to track each edge twice so that we
492 * can reference it from either side conveniently. Also I'm
493 * going to allocate _five_ bytes per tile, rather than the
494 * obvious four, so that I can index edgestate[(y*w+x) * 5 + d]
495 * where d is 1,2,4,8 and they never overlap.
497 edgestate
= snewn((w
* h
- 1) * 5 + 9, unsigned char);
498 memset(edgestate
, 0, (w
* h
- 1) * 5 + 9);
501 * deadends tracks which edges have dead ends on them. It is
502 * indexed by tile and direction: deadends[(y*w+x) * 5 + d]
503 * tells you whether heading out of tile (x,y) in direction d
504 * can reach a limited amount of the grid. Values are area+1
505 * (no dead end known) or less than that (can reach _at most_
506 * this many other tiles by heading this way out of this tile).
508 deadends
= snewn((w
* h
- 1) * 5 + 9, int);
509 for (i
= 0; i
< (w
* h
- 1) * 5 + 9; i
++)
510 deadends
[i
] = area
+1;
513 * equivalence tracks which sets of tiles are known to be
514 * connected to one another, so we can avoid creating loops by
515 * linking together tiles which are already linked through
518 * This is a disjoint set forest structure: equivalence[i]
519 * contains the index of another member of the equivalence
520 * class containing i, or contains i itself for precisely one
521 * member in each such class. To find a representative member
522 * of the equivalence class containing i, you keep replacing i
523 * with equivalence[i] until it stops changing; then you go
524 * _back_ along the same path and point everything on it
525 * directly at the representative member so as to speed up
526 * future searches. Then you test equivalence between tiles by
527 * finding the representative of each tile and seeing if
528 * they're the same; and you create new equivalence (merge
529 * classes) by finding the representative of each tile and
530 * setting equivalence[one]=the_other.
532 equivalence
= snew_dsf(w
* h
);
535 * On a non-wrapping grid, we instantly know that all the edges
536 * round the edge are closed.
539 for (i
= 0; i
< w
; i
++) {
540 edgestate
[i
* 5 + 2] = edgestate
[((h
-1) * w
+ i
) * 5 + 8] = 2;
542 for (i
= 0; i
< h
; i
++) {
543 edgestate
[(i
* w
+ w
-1) * 5 + 1] = edgestate
[(i
* w
) * 5 + 4] = 2;
548 * If we have barriers available, we can mark those edges as
552 for (y
= 0; y
< h
; y
++) for (x
= 0; x
< w
; x
++) {
554 for (d
= 1; d
<= 8; d
+= d
) {
555 if (barriers
[y
*w
+x
] & d
) {
558 * In principle the barrier list should already
559 * contain each barrier from each side, but
560 * let's not take chances with our internal
563 OFFSETWH(x2
, y2
, x
, y
, d
, w
, h
);
564 edgestate
[(y
*w
+x
) * 5 + d
] = 2;
565 edgestate
[(y2
*w
+x2
) * 5 + F(d
)] = 2;
572 * Since most deductions made by this solver are local (the
573 * exception is loop avoidance, where joining two tiles
574 * together on one side of the grid can theoretically permit a
575 * fresh deduction on the other), we can address the scaling
576 * problem inherent in iterating repeatedly over the entire
577 * grid by instead working with a to-do list.
579 todo
= todo_new(w
* h
);
582 * Main deductive loop.
584 done_something
= TRUE
; /* prevent instant termination! */
589 * Take a tile index off the todo list and process it.
591 index
= todo_get(todo
);
594 * If we have run out of immediate things to do, we
595 * have no choice but to scan the whole grid for
596 * longer-range things we've missed. Hence, I now add
597 * every square on the grid back on to the to-do list.
598 * I also set `done_something' to FALSE at this point;
599 * if we later come back here and find it still FALSE,
600 * we will know we've scanned the entire grid without
601 * finding anything new to do, and we can terminate.
605 for (i
= 0; i
< w
*h
; i
++)
607 done_something
= FALSE
;
609 index
= todo_get(todo
);
615 int d
, ourclass
= dsf_canonify(equivalence
, y
*w
+x
);
618 deadendmax
[1] = deadendmax
[2] = deadendmax
[4] = deadendmax
[8] = 0;
620 for (i
= j
= 0; i
< 4 && tilestate
[(y
*w
+x
) * 4 + i
] != 255; i
++) {
622 int nnondeadends
, nondeadends
[4], deadendtotal
;
623 int nequiv
, equiv
[5];
624 int val
= tilestate
[(y
*w
+x
) * 4 + i
];
627 nnondeadends
= deadendtotal
= 0;
630 for (d
= 1; d
<= 8; d
+= d
) {
632 * Immediately rule out this orientation if it
633 * conflicts with any known edge.
635 if ((edgestate
[(y
*w
+x
) * 5 + d
] == 1 && !(val
& d
)) ||
636 (edgestate
[(y
*w
+x
) * 5 + d
] == 2 && (val
& d
)))
641 * Count up the dead-end statistics.
643 if (deadends
[(y
*w
+x
) * 5 + d
] <= area
) {
644 deadendtotal
+= deadends
[(y
*w
+x
) * 5 + d
];
646 nondeadends
[nnondeadends
++] = d
;
650 * Ensure we aren't linking to any tiles,
651 * through edges not already known to be
652 * open, which create a loop.
654 if (edgestate
[(y
*w
+x
) * 5 + d
] == 0) {
657 OFFSETWH(x2
, y2
, x
, y
, d
, w
, h
);
658 c
= dsf_canonify(equivalence
, y2
*w
+x2
);
659 for (k
= 0; k
< nequiv
; k
++)
670 if (nnondeadends
== 0) {
672 * If this orientation links together dead-ends
673 * with a total area of less than the entire
674 * grid, it is invalid.
676 * (We add 1 to deadendtotal because of the
677 * tile itself, of course; one tile linking
678 * dead ends of size 2 and 3 forms a subnetwork
679 * with a total area of 6, not 5.)
681 if (deadendtotal
> 0 && deadendtotal
+1 < area
)
683 } else if (nnondeadends
== 1) {
685 * If this orientation links together one or
686 * more dead-ends with precisely one
687 * non-dead-end, then we may have to mark that
688 * non-dead-end as a dead end going the other
689 * way. However, it depends on whether all
690 * other orientations share the same property.
693 if (deadendmax
[nondeadends
[0]] < deadendtotal
)
694 deadendmax
[nondeadends
[0]] = deadendtotal
;
697 * If this orientation links together two or
698 * more non-dead-ends, then we can rule out the
699 * possibility of putting in new dead-end
700 * markings in those directions.
703 for (k
= 0; k
< nnondeadends
; k
++)
704 deadendmax
[nondeadends
[k
]] = area
+1;
708 tilestate
[(y
*w
+x
) * 4 + j
++] = val
;
709 #ifdef SOLVER_DIAGNOSTICS
711 printf("ruling out orientation %x at %d,%d\n", val
, x
, y
);
715 assert(j
> 0); /* we can't lose _all_ possibilities! */
718 done_something
= TRUE
;
721 * We have ruled out at least one tile orientation.
722 * Make sure the rest are blanked.
725 tilestate
[(y
*w
+x
) * 4 + j
++] = 255;
729 * Now go through the tile orientations again and see
730 * if we've deduced anything new about any edges.
736 for (i
= 0; i
< 4 && tilestate
[(y
*w
+x
) * 4 + i
] != 255; i
++) {
737 a
&= tilestate
[(y
*w
+x
) * 4 + i
];
738 o
|= tilestate
[(y
*w
+x
) * 4 + i
];
740 for (d
= 1; d
<= 8; d
+= d
)
741 if (edgestate
[(y
*w
+x
) * 5 + d
] == 0) {
743 OFFSETWH(x2
, y2
, x
, y
, d
, w
, h
);
746 /* This edge is open in all orientations. */
747 #ifdef SOLVER_DIAGNOSTICS
748 printf("marking edge %d,%d:%d open\n", x
, y
, d
);
750 edgestate
[(y
*w
+x
) * 5 + d
] = 1;
751 edgestate
[(y2
*w
+x2
) * 5 + d2
] = 1;
752 dsf_merge(equivalence
, y
*w
+x
, y2
*w
+x2
);
753 done_something
= TRUE
;
754 todo_add(todo
, y2
*w
+x2
);
755 } else if (!(o
& d
)) {
756 /* This edge is closed in all orientations. */
757 #ifdef SOLVER_DIAGNOSTICS
758 printf("marking edge %d,%d:%d closed\n", x
, y
, d
);
760 edgestate
[(y
*w
+x
) * 5 + d
] = 2;
761 edgestate
[(y2
*w
+x2
) * 5 + d2
] = 2;
762 done_something
= TRUE
;
763 todo_add(todo
, y2
*w
+x2
);
770 * Now check the dead-end markers and see if any of
771 * them has lowered from the real ones.
773 for (d
= 1; d
<= 8; d
+= d
) {
775 OFFSETWH(x2
, y2
, x
, y
, d
, w
, h
);
777 if (deadendmax
[d
] > 0 &&
778 deadends
[(y2
*w
+x2
) * 5 + d2
] > deadendmax
[d
]) {
779 #ifdef SOLVER_DIAGNOSTICS
780 printf("setting dead end value %d,%d:%d to %d\n",
781 x2
, y2
, d2
, deadendmax
[d
]);
783 deadends
[(y2
*w
+x2
) * 5 + d2
] = deadendmax
[d
];
784 done_something
= TRUE
;
785 todo_add(todo
, y2
*w
+x2
);
793 * Mark all completely determined tiles as locked.
796 for (i
= 0; i
< w
*h
; i
++) {
797 if (tilestate
[i
* 4 + 1] == 255) {
798 assert(tilestate
[i
* 4 + 0] != 255);
799 tiles
[i
] = tilestate
[i
* 4] | LOCKED
;
807 * Free up working space.
818 /* ----------------------------------------------------------------------
819 * Randomly select a new game description.
823 * Function to randomly perturb an ambiguous section in a grid, to
824 * attempt to ensure unique solvability.
826 static void perturb(int w
, int h
, unsigned char *tiles
, int wrapping
,
827 random_state
*rs
, int startx
, int starty
, int startd
)
829 struct xyd
*perimeter
, *perim2
, *loop
[2], looppos
[2];
830 int nperim
, perimsize
, nloop
[2], loopsize
[2];
834 * We know that the tile at (startx,starty) is part of an
835 * ambiguous section, and we also know that its neighbour in
836 * direction startd is fully specified. We begin by tracing all
837 * the way round the ambiguous area.
839 nperim
= perimsize
= 0;
844 #ifdef PERTURB_DIAGNOSTICS
845 printf("perturb %d,%d:%d\n", x
, y
, d
);
850 if (nperim
>= perimsize
) {
851 perimsize
= perimsize
* 3 / 2 + 32;
852 perimeter
= sresize(perimeter
, perimsize
, struct xyd
);
854 perimeter
[nperim
].x
= x
;
855 perimeter
[nperim
].y
= y
;
856 perimeter
[nperim
].direction
= d
;
858 #ifdef PERTURB_DIAGNOSTICS
859 printf("perimeter: %d,%d:%d\n", x
, y
, d
);
863 * First, see if we can simply turn left from where we are
864 * and find another locked square.
867 OFFSETWH(x2
, y2
, x
, y
, d2
, w
, h
);
868 if ((!wrapping
&& (abs(x2
-x
) > 1 || abs(y2
-y
) > 1)) ||
869 (tiles
[y2
*w
+x2
] & LOCKED
)) {
873 * Failing that, step left into the new square and look
878 OFFSETWH(x2
, y2
, x
, y
, d
, w
, h
);
879 if ((wrapping
|| (abs(x2
-x
) <= 1 && abs(y2
-y
) <= 1)) &&
880 !(tiles
[y2
*w
+x2
] & LOCKED
)) {
882 * And failing _that_, we're going to have to step
883 * forward into _that_ square and look right at the
884 * same locked square as we started with.
892 } while (x
!= startx
|| y
!= starty
|| d
!= startd
);
895 * Our technique for perturbing this ambiguous area is to
896 * search round its edge for a join we can make: that is, an
897 * edge on the perimeter which is (a) not currently connected,
898 * and (b) connecting it would not yield a full cross on either
899 * side. Then we make that join, search round the network to
900 * find the loop thus constructed, and sever the loop at a
901 * randomly selected other point.
903 perim2
= snewn(nperim
, struct xyd
);
904 memcpy(perim2
, perimeter
, nperim
* sizeof(struct xyd
));
905 /* Shuffle the perimeter, so as to search it without directional bias. */
906 shuffle(perim2
, nperim
, sizeof(*perim2
), rs
);
907 for (i
= 0; i
< nperim
; i
++) {
912 d
= perim2
[i
].direction
;
914 OFFSETWH(x2
, y2
, x
, y
, d
, w
, h
);
915 if (!wrapping
&& (abs(x2
-x
) > 1 || abs(y2
-y
) > 1))
916 continue; /* can't link across non-wrapping border */
917 if (tiles
[y
*w
+x
] & d
)
918 continue; /* already linked in this direction! */
919 if (((tiles
[y
*w
+x
] | d
) & 15) == 15)
920 continue; /* can't turn this tile into a cross */
921 if (((tiles
[y2
*w
+x2
] | F(d
)) & 15) == 15)
922 continue; /* can't turn other tile into a cross */
925 * We've found the point at which we're going to make a new
928 #ifdef PERTURB_DIAGNOSTICS
929 printf("linking %d,%d:%d\n", x
, y
, d
);
932 tiles
[y2
*w
+x2
] |= F(d
);
939 return; /* nothing we can do! */
942 * Now we've constructed a new link, we need to find the entire
943 * loop of which it is a part.
945 * In principle, this involves doing a complete search round
946 * the network. However, I anticipate that in the vast majority
947 * of cases the loop will be quite small, so what I'm going to
948 * do is make _two_ searches round the network in parallel, one
949 * keeping its metaphorical hand on the left-hand wall while
950 * the other keeps its hand on the right. As soon as one of
951 * them gets back to its starting point, I abandon the other.
953 for (i
= 0; i
< 2; i
++) {
954 loopsize
[i
] = nloop
[i
] = 0;
958 looppos
[i
].direction
= d
;
961 for (i
= 0; i
< 2; i
++) {
966 d
= looppos
[i
].direction
;
968 OFFSETWH(x2
, y2
, x
, y
, d
, w
, h
);
971 * Add this path segment to the loop, unless it exactly
972 * reverses the previous one on the loop in which case
973 * we take it away again.
975 #ifdef PERTURB_DIAGNOSTICS
976 printf("looppos[%d] = %d,%d:%d\n", i
, x
, y
, d
);
979 loop
[i
][nloop
[i
]-1].x
== x2
&&
980 loop
[i
][nloop
[i
]-1].y
== y2
&&
981 loop
[i
][nloop
[i
]-1].direction
== F(d
)) {
982 #ifdef PERTURB_DIAGNOSTICS
983 printf("removing path segment %d,%d:%d from loop[%d]\n",
988 if (nloop
[i
] >= loopsize
[i
]) {
989 loopsize
[i
] = loopsize
[i
] * 3 / 2 + 32;
990 loop
[i
] = sresize(loop
[i
], loopsize
[i
], struct xyd
);
992 #ifdef PERTURB_DIAGNOSTICS
993 printf("adding path segment %d,%d:%d to loop[%d]\n",
996 loop
[i
][nloop
[i
]++] = looppos
[i
];
999 #ifdef PERTURB_DIAGNOSTICS
1000 printf("tile at new location is %x\n", tiles
[y2
*w
+x2
] & 0xF);
1003 for (j
= 0; j
< 4; j
++) {
1008 #ifdef PERTURB_DIAGNOSTICS
1009 printf("trying dir %d\n", d
);
1011 if (tiles
[y2
*w
+x2
] & d
) {
1014 looppos
[i
].direction
= d
;
1020 assert(nloop
[i
] > 0);
1022 if (looppos
[i
].x
== loop
[i
][0].x
&&
1023 looppos
[i
].y
== loop
[i
][0].y
&&
1024 looppos
[i
].direction
== loop
[i
][0].direction
) {
1025 #ifdef PERTURB_DIAGNOSTICS
1026 printf("loop %d finished tracking\n", i
);
1030 * Having found our loop, we now sever it at a
1031 * randomly chosen point - absolutely any will do -
1032 * which is not the one we joined it at to begin
1033 * with. Conveniently, the one we joined it at is
1034 * loop[i][0], so we just avoid that one.
1036 j
= random_upto(rs
, nloop
[i
]-1) + 1;
1039 d
= loop
[i
][j
].direction
;
1040 OFFSETWH(x2
, y2
, x
, y
, d
, w
, h
);
1042 tiles
[y2
*w
+x2
] &= ~F(d
);
1054 * Finally, we must mark the entire disputed section as locked,
1055 * to prevent the perturb function being called on it multiple
1058 * To do this, we _sort_ the perimeter of the area. The
1059 * existing xyd_cmp function will arrange things into columns
1060 * for us, in such a way that each column has the edges in
1061 * vertical order. Then we can work down each column and fill
1062 * in all the squares between an up edge and a down edge.
1064 qsort(perimeter
, nperim
, sizeof(struct xyd
), xyd_cmp
);
1066 for (i
= 0; i
<= nperim
; i
++) {
1067 if (i
== nperim
|| perimeter
[i
].x
> x
) {
1069 * Fill in everything from the last Up edge to the
1070 * bottom of the grid, if necessary.
1074 #ifdef PERTURB_DIAGNOSTICS
1075 printf("resolved: locking tile %d,%d\n", x
, y
);
1077 tiles
[y
* w
+ x
] |= LOCKED
;
1090 if (perimeter
[i
].direction
== U
) {
1093 } else if (perimeter
[i
].direction
== D
) {
1095 * Fill in everything from the last Up edge to here.
1097 assert(x
== perimeter
[i
].x
&& y
<= perimeter
[i
].y
);
1098 while (y
<= perimeter
[i
].y
) {
1099 #ifdef PERTURB_DIAGNOSTICS
1100 printf("resolved: locking tile %d,%d\n", x
, y
);
1102 tiles
[y
* w
+ x
] |= LOCKED
;
1112 static char *new_game_desc(game_params
*params
, random_state
*rs
,
1113 char **aux
, int interactive
)
1115 tree234
*possibilities
, *barriertree
;
1116 int w
, h
, x
, y
, cx
, cy
, nbarriers
;
1117 unsigned char *tiles
, *barriers
;
1126 tiles
= snewn(w
* h
, unsigned char);
1127 barriers
= snewn(w
* h
, unsigned char);
1131 memset(tiles
, 0, w
* h
);
1132 memset(barriers
, 0, w
* h
);
1135 * Construct the unshuffled grid.
1137 * To do this, we simply start at the centre point, repeatedly
1138 * choose a random possibility out of the available ways to
1139 * extend a used square into an unused one, and do it. After
1140 * extending the third line out of a square, we remove the
1141 * fourth from the possibilities list to avoid any full-cross
1142 * squares (which would make the game too easy because they
1143 * only have one orientation).
1145 * The slightly worrying thing is the avoidance of full-cross
1146 * squares. Can this cause our unsophisticated construction
1147 * algorithm to paint itself into a corner, by getting into a
1148 * situation where there are some unreached squares and the
1149 * only way to reach any of them is to extend a T-piece into a
1152 * Answer: no it can't, and here's a proof.
1154 * Any contiguous group of such unreachable squares must be
1155 * surrounded on _all_ sides by T-pieces pointing away from the
1156 * group. (If not, then there is a square which can be extended
1157 * into one of the `unreachable' ones, and so it wasn't
1158 * unreachable after all.) In particular, this implies that
1159 * each contiguous group of unreachable squares must be
1160 * rectangular in shape (any deviation from that yields a
1161 * non-T-piece next to an `unreachable' square).
1163 * So we have a rectangle of unreachable squares, with T-pieces
1164 * forming a solid border around the rectangle. The corners of
1165 * that border must be connected (since every tile connects all
1166 * the lines arriving in it), and therefore the border must
1167 * form a closed loop around the rectangle.
1169 * But this can't have happened in the first place, since we
1170 * _know_ we've avoided creating closed loops! Hence, no such
1171 * situation can ever arise, and the naive grid construction
1172 * algorithm will guaranteeably result in a complete grid
1173 * containing no unreached squares, no full crosses _and_ no
1176 possibilities
= newtree234(xyd_cmp_nc
);
1179 add234(possibilities
, new_xyd(cx
, cy
, R
));
1181 add234(possibilities
, new_xyd(cx
, cy
, U
));
1183 add234(possibilities
, new_xyd(cx
, cy
, L
));
1185 add234(possibilities
, new_xyd(cx
, cy
, D
));
1187 while (count234(possibilities
) > 0) {
1190 int x1
, y1
, d1
, x2
, y2
, d2
, d
;
1193 * Extract a randomly chosen possibility from the list.
1195 i
= random_upto(rs
, count234(possibilities
));
1196 xyd
= delpos234(possibilities
, i
);
1199 d1
= xyd
->direction
;
1202 OFFSET(x2
, y2
, x1
, y1
, d1
, params
);
1204 #ifdef GENERATION_DIAGNOSTICS
1205 printf("picked (%d,%d,%c) <-> (%d,%d,%c)\n",
1206 x1
, y1
, "0RU3L567D9abcdef"[d1
], x2
, y2
, "0RU3L567D9abcdef"[d2
]);
1210 * Make the connection. (We should be moving to an as yet
1213 index(params
, tiles
, x1
, y1
) |= d1
;
1214 assert(index(params
, tiles
, x2
, y2
) == 0);
1215 index(params
, tiles
, x2
, y2
) |= d2
;
1218 * If we have created a T-piece, remove its last
1221 if (COUNT(index(params
, tiles
, x1
, y1
)) == 3) {
1222 struct xyd xyd1
, *xydp
;
1226 xyd1
.direction
= 0x0F ^ index(params
, tiles
, x1
, y1
);
1228 xydp
= find234(possibilities
, &xyd1
, NULL
);
1231 #ifdef GENERATION_DIAGNOSTICS
1232 printf("T-piece; removing (%d,%d,%c)\n",
1233 xydp
->x
, xydp
->y
, "0RU3L567D9abcdef"[xydp
->direction
]);
1235 del234(possibilities
, xydp
);
1241 * Remove all other possibilities that were pointing at the
1242 * tile we've just moved into.
1244 for (d
= 1; d
< 0x10; d
<<= 1) {
1246 struct xyd xyd1
, *xydp
;
1248 OFFSET(x3
, y3
, x2
, y2
, d
, params
);
1253 xyd1
.direction
= d3
;
1255 xydp
= find234(possibilities
, &xyd1
, NULL
);
1258 #ifdef GENERATION_DIAGNOSTICS
1259 printf("Loop avoidance; removing (%d,%d,%c)\n",
1260 xydp
->x
, xydp
->y
, "0RU3L567D9abcdef"[xydp
->direction
]);
1262 del234(possibilities
, xydp
);
1268 * Add new possibilities to the list for moving _out_ of
1269 * the tile we have just moved into.
1271 for (d
= 1; d
< 0x10; d
<<= 1) {
1275 continue; /* we've got this one already */
1277 if (!params
->wrapping
) {
1278 if (d
== U
&& y2
== 0)
1280 if (d
== D
&& y2
== h
-1)
1282 if (d
== L
&& x2
== 0)
1284 if (d
== R
&& x2
== w
-1)
1288 OFFSET(x3
, y3
, x2
, y2
, d
, params
);
1290 if (index(params
, tiles
, x3
, y3
))
1291 continue; /* this would create a loop */
1293 #ifdef GENERATION_DIAGNOSTICS
1294 printf("New frontier; adding (%d,%d,%c)\n",
1295 x2
, y2
, "0RU3L567D9abcdef"[d
]);
1297 add234(possibilities
, new_xyd(x2
, y2
, d
));
1300 /* Having done that, we should have no possibilities remaining. */
1301 assert(count234(possibilities
) == 0);
1302 freetree234(possibilities
);
1304 if (params
->unique
) {
1308 * Run the solver to check unique solubility.
1310 while (!net_solver(w
, h
, tiles
, NULL
, params
->wrapping
)) {
1314 * We expect (in most cases) that most of the grid will
1315 * be uniquely specified already, and the remaining
1316 * ambiguous sections will be small and separate. So
1317 * our strategy is to find each individual such
1318 * section, and perform a perturbation on the network
1321 for (y
= 0; y
< h
; y
++) for (x
= 0; x
< w
; x
++) {
1322 if (x
+1 < w
&& ((tiles
[y
*w
+x
] ^ tiles
[y
*w
+x
+1]) & LOCKED
)) {
1324 if (tiles
[y
*w
+x
] & LOCKED
)
1325 perturb(w
, h
, tiles
, params
->wrapping
, rs
, x
+1, y
, L
);
1327 perturb(w
, h
, tiles
, params
->wrapping
, rs
, x
, y
, R
);
1329 if (y
+1 < h
&& ((tiles
[y
*w
+x
] ^ tiles
[(y
+1)*w
+x
]) & LOCKED
)) {
1331 if (tiles
[y
*w
+x
] & LOCKED
)
1332 perturb(w
, h
, tiles
, params
->wrapping
, rs
, x
, y
+1, U
);
1334 perturb(w
, h
, tiles
, params
->wrapping
, rs
, x
, y
, D
);
1339 * Now n counts the number of ambiguous sections we
1340 * have fiddled with. If we haven't managed to decrease
1341 * it from the last time we ran the solver, give up and
1342 * regenerate the entire grid.
1344 if (prevn
!= -1 && prevn
<= n
)
1345 goto begin_generation
; /* (sorry) */
1351 * The solver will have left a lot of LOCKED bits lying
1352 * around in the tiles array. Remove them.
1354 for (x
= 0; x
< w
*h
; x
++)
1355 tiles
[x
] &= ~LOCKED
;
1359 * Now compute a list of the possible barrier locations.
1361 barriertree
= newtree234(xyd_cmp_nc
);
1362 for (y
= 0; y
< h
; y
++) {
1363 for (x
= 0; x
< w
; x
++) {
1365 if (!(index(params
, tiles
, x
, y
) & R
) &&
1366 (params
->wrapping
|| x
< w
-1))
1367 add234(barriertree
, new_xyd(x
, y
, R
));
1368 if (!(index(params
, tiles
, x
, y
) & D
) &&
1369 (params
->wrapping
|| y
< h
-1))
1370 add234(barriertree
, new_xyd(x
, y
, D
));
1375 * Save the unshuffled grid in aux.
1381 solution
= snewn(w
* h
+ 1, char);
1382 for (i
= 0; i
< w
* h
; i
++)
1383 solution
[i
] = "0123456789abcdef"[tiles
[i
] & 0xF];
1384 solution
[w
*h
] = '\0';
1390 * Now shuffle the grid.
1392 for (y
= 0; y
< h
; y
++) {
1393 for (x
= 0; x
< w
; x
++) {
1394 int orig
= index(params
, tiles
, x
, y
);
1395 int rot
= random_upto(rs
, 4);
1396 index(params
, tiles
, x
, y
) = ROT(orig
, rot
);
1401 * And now choose barrier locations. (We carefully do this
1402 * _after_ shuffling, so that changing the barrier rate in the
1403 * params while keeping the random seed the same will give the
1404 * same shuffled grid and _only_ change the barrier locations.
1405 * Also the way we choose barrier locations, by repeatedly
1406 * choosing one possibility from the list until we have enough,
1407 * is designed to ensure that raising the barrier rate while
1408 * keeping the seed the same will provide a superset of the
1409 * previous barrier set - i.e. if you ask for 10 barriers, and
1410 * then decide that's still too hard and ask for 20, you'll get
1411 * the original 10 plus 10 more, rather than getting 20 new
1412 * ones and the chance of remembering your first 10.)
1414 nbarriers
= (int)(params
->barrier_probability
* count234(barriertree
));
1415 assert(nbarriers
>= 0 && nbarriers
<= count234(barriertree
));
1417 while (nbarriers
> 0) {
1420 int x1
, y1
, d1
, x2
, y2
, d2
;
1423 * Extract a randomly chosen barrier from the list.
1425 i
= random_upto(rs
, count234(barriertree
));
1426 xyd
= delpos234(barriertree
, i
);
1428 assert(xyd
!= NULL
);
1432 d1
= xyd
->direction
;
1435 OFFSET(x2
, y2
, x1
, y1
, d1
, params
);
1438 index(params
, barriers
, x1
, y1
) |= d1
;
1439 index(params
, barriers
, x2
, y2
) |= d2
;
1445 * Clean up the rest of the barrier list.
1450 while ( (xyd
= delpos234(barriertree
, 0)) != NULL
)
1453 freetree234(barriertree
);
1457 * Finally, encode the grid into a string game description.
1459 * My syntax is extremely simple: each square is encoded as a
1460 * hex digit in which bit 0 means a connection on the right,
1461 * bit 1 means up, bit 2 left and bit 3 down. (i.e. the same
1462 * encoding as used internally). Each digit is followed by
1463 * optional barrier indicators: `v' means a vertical barrier to
1464 * the right of it, and `h' means a horizontal barrier below
1467 desc
= snewn(w
* h
* 3 + 1, char);
1469 for (y
= 0; y
< h
; y
++) {
1470 for (x
= 0; x
< w
; x
++) {
1471 *p
++ = "0123456789abcdef"[index(params
, tiles
, x
, y
)];
1472 if ((params
->wrapping
|| x
< w
-1) &&
1473 (index(params
, barriers
, x
, y
) & R
))
1475 if ((params
->wrapping
|| y
< h
-1) &&
1476 (index(params
, barriers
, x
, y
) & D
))
1480 assert(p
- desc
<= w
*h
*3);
1489 static char *validate_desc(game_params
*params
, char *desc
)
1491 int w
= params
->width
, h
= params
->height
;
1494 for (i
= 0; i
< w
*h
; i
++) {
1495 if (*desc
>= '0' && *desc
<= '9')
1497 else if (*desc
>= 'a' && *desc
<= 'f')
1499 else if (*desc
>= 'A' && *desc
<= 'F')
1502 return "Game description shorter than expected";
1504 return "Game description contained unexpected character";
1506 while (*desc
== 'h' || *desc
== 'v')
1510 return "Game description longer than expected";
1515 /* ----------------------------------------------------------------------
1516 * Construct an initial game state, given a description and parameters.
1519 static game_state
*new_game(midend
*me
, game_params
*params
, char *desc
)
1524 assert(params
->width
> 0 && params
->height
> 0);
1525 assert(params
->width
> 1 || params
->height
> 1);
1528 * Create a blank game state.
1530 state
= snew(game_state
);
1531 w
= state
->width
= params
->width
;
1532 h
= state
->height
= params
->height
;
1533 state
->wrapping
= params
->wrapping
;
1534 state
->last_rotate_dir
= state
->last_rotate_x
= state
->last_rotate_y
= 0;
1535 state
->completed
= state
->used_solve
= FALSE
;
1536 state
->tiles
= snewn(state
->width
* state
->height
, unsigned char);
1537 memset(state
->tiles
, 0, state
->width
* state
->height
);
1538 state
->barriers
= snewn(state
->width
* state
->height
, unsigned char);
1539 memset(state
->barriers
, 0, state
->width
* state
->height
);
1542 * Parse the game description into the grid.
1544 for (y
= 0; y
< h
; y
++) {
1545 for (x
= 0; x
< w
; x
++) {
1546 if (*desc
>= '0' && *desc
<= '9')
1547 tile(state
, x
, y
) = *desc
- '0';
1548 else if (*desc
>= 'a' && *desc
<= 'f')
1549 tile(state
, x
, y
) = *desc
- 'a' + 10;
1550 else if (*desc
>= 'A' && *desc
<= 'F')
1551 tile(state
, x
, y
) = *desc
- 'A' + 10;
1554 while (*desc
== 'h' || *desc
== 'v') {
1561 OFFSET(x2
, y2
, x
, y
, d1
, state
);
1564 barrier(state
, x
, y
) |= d1
;
1565 barrier(state
, x2
, y2
) |= d2
;
1573 * Set up border barriers if this is a non-wrapping game.
1575 if (!state
->wrapping
) {
1576 for (x
= 0; x
< state
->width
; x
++) {
1577 barrier(state
, x
, 0) |= U
;
1578 barrier(state
, x
, state
->height
-1) |= D
;
1580 for (y
= 0; y
< state
->height
; y
++) {
1581 barrier(state
, 0, y
) |= L
;
1582 barrier(state
, state
->width
-1, y
) |= R
;
1586 * We check whether this is de-facto a non-wrapping game
1587 * despite the parameters, in case we were passed the
1588 * description of a non-wrapping game. This is so that we
1589 * can change some aspects of the UI behaviour.
1591 state
->wrapping
= FALSE
;
1592 for (x
= 0; x
< state
->width
; x
++)
1593 if (!(barrier(state
, x
, 0) & U
) ||
1594 !(barrier(state
, x
, state
->height
-1) & D
))
1595 state
->wrapping
= TRUE
;
1596 for (y
= 0; y
< state
->width
; y
++)
1597 if (!(barrier(state
, 0, y
) & L
) ||
1598 !(barrier(state
, state
->width
-1, y
) & R
))
1599 state
->wrapping
= TRUE
;
1605 static game_state
*dup_game(game_state
*state
)
1609 ret
= snew(game_state
);
1610 ret
->width
= state
->width
;
1611 ret
->height
= state
->height
;
1612 ret
->wrapping
= state
->wrapping
;
1613 ret
->completed
= state
->completed
;
1614 ret
->used_solve
= state
->used_solve
;
1615 ret
->last_rotate_dir
= state
->last_rotate_dir
;
1616 ret
->last_rotate_x
= state
->last_rotate_x
;
1617 ret
->last_rotate_y
= state
->last_rotate_y
;
1618 ret
->tiles
= snewn(state
->width
* state
->height
, unsigned char);
1619 memcpy(ret
->tiles
, state
->tiles
, state
->width
* state
->height
);
1620 ret
->barriers
= snewn(state
->width
* state
->height
, unsigned char);
1621 memcpy(ret
->barriers
, state
->barriers
, state
->width
* state
->height
);
1626 static void free_game(game_state
*state
)
1628 sfree(state
->tiles
);
1629 sfree(state
->barriers
);
1633 static char *solve_game(game_state
*state
, game_state
*currstate
,
1634 char *aux
, char **error
)
1636 unsigned char *tiles
;
1638 int retlen
, retsize
;
1641 tiles
= snewn(state
->width
* state
->height
, unsigned char);
1645 * Run the internal solver on the provided grid. This might
1646 * not yield a complete solution.
1648 memcpy(tiles
, state
->tiles
, state
->width
* state
->height
);
1649 net_solver(state
->width
, state
->height
, tiles
,
1650 state
->barriers
, state
->wrapping
);
1652 for (i
= 0; i
< state
->width
* state
->height
; i
++) {
1655 if (c
>= '0' && c
<= '9')
1657 else if (c
>= 'a' && c
<= 'f')
1658 tiles
[i
] = c
- 'a' + 10;
1659 else if (c
>= 'A' && c
<= 'F')
1660 tiles
[i
] = c
- 'A' + 10;
1667 * Now construct a string which can be passed to execute_move()
1668 * to transform the current grid into the solved one.
1671 ret
= snewn(retsize
, char);
1673 ret
[retlen
++] = 'S';
1675 for (i
= 0; i
< state
->width
* state
->height
; i
++) {
1676 int from
= currstate
->tiles
[i
], to
= tiles
[i
];
1677 int ft
= from
& (R
|L
|U
|D
), tt
= to
& (R
|L
|U
|D
);
1678 int x
= i
% state
->width
, y
= i
/ state
->width
;
1680 char buf
[80], *p
= buf
;
1683 continue; /* nothing needs doing at all */
1686 * To transform this tile into the desired tile: first
1687 * unlock the tile if it's locked, then rotate it if
1688 * necessary, then lock it if necessary.
1691 p
+= sprintf(p
, ";L%d,%d", x
, y
);
1695 else if (tt
== C(ft
))
1697 else if (tt
== F(ft
))
1704 p
+= sprintf(p
, ";%c%d,%d", chr
, x
, y
);
1707 p
+= sprintf(p
, ";L%d,%d", x
, y
);
1710 if (retlen
+ (p
- buf
) >= retsize
) {
1711 retsize
= retlen
+ (p
- buf
) + 512;
1712 ret
= sresize(ret
, retsize
, char);
1714 memcpy(ret
+retlen
, buf
, p
- buf
);
1719 assert(retlen
< retsize
);
1721 ret
= sresize(ret
, retlen
+1, char);
1728 static char *game_text_format(game_state
*state
)
1733 /* ----------------------------------------------------------------------
1738 * Compute which squares are reachable from the centre square, as a
1739 * quick visual aid to determining how close the game is to
1740 * completion. This is also a simple way to tell if the game _is_
1741 * completed - just call this function and see whether every square
1744 static unsigned char *compute_active(game_state
*state
, int cx
, int cy
)
1746 unsigned char *active
;
1750 active
= snewn(state
->width
* state
->height
, unsigned char);
1751 memset(active
, 0, state
->width
* state
->height
);
1754 * We only store (x,y) pairs in todo, but it's easier to reuse
1755 * xyd_cmp and just store direction 0 every time.
1757 todo
= newtree234(xyd_cmp_nc
);
1758 index(state
, active
, cx
, cy
) = ACTIVE
;
1759 add234(todo
, new_xyd(cx
, cy
, 0));
1761 while ( (xyd
= delpos234(todo
, 0)) != NULL
) {
1762 int x1
, y1
, d1
, x2
, y2
, d2
;
1768 for (d1
= 1; d1
< 0x10; d1
<<= 1) {
1769 OFFSET(x2
, y2
, x1
, y1
, d1
, state
);
1773 * If the next tile in this direction is connected to
1774 * us, and there isn't a barrier in the way, and it
1775 * isn't already marked active, then mark it active and
1776 * add it to the to-examine list.
1778 if ((tile(state
, x1
, y1
) & d1
) &&
1779 (tile(state
, x2
, y2
) & d2
) &&
1780 !(barrier(state
, x1
, y1
) & d1
) &&
1781 !index(state
, active
, x2
, y2
)) {
1782 index(state
, active
, x2
, y2
) = ACTIVE
;
1783 add234(todo
, new_xyd(x2
, y2
, 0));
1787 /* Now we expect the todo list to have shrunk to zero size. */
1788 assert(count234(todo
) == 0);
1795 int org_x
, org_y
; /* origin */
1796 int cx
, cy
; /* source tile (game coordinates) */
1799 random_state
*rs
; /* used for jumbling */
1802 static game_ui
*new_ui(game_state
*state
)
1806 game_ui
*ui
= snew(game_ui
);
1807 ui
->org_x
= ui
->org_y
= 0;
1808 ui
->cur_x
= ui
->cx
= state
->width
/ 2;
1809 ui
->cur_y
= ui
->cy
= state
->height
/ 2;
1810 ui
->cur_visible
= FALSE
;
1811 get_random_seed(&seed
, &seedsize
);
1812 ui
->rs
= random_new(seed
, seedsize
);
1818 static void free_ui(game_ui
*ui
)
1820 random_free(ui
->rs
);
1824 static char *encode_ui(game_ui
*ui
)
1828 * We preserve the origin and centre-point coordinates over a
1831 sprintf(buf
, "O%d,%d;C%d,%d", ui
->org_x
, ui
->org_y
, ui
->cx
, ui
->cy
);
1835 static void decode_ui(game_ui
*ui
, char *encoding
)
1837 sscanf(encoding
, "O%d,%d;C%d,%d",
1838 &ui
->org_x
, &ui
->org_y
, &ui
->cx
, &ui
->cy
);
1841 static void game_changed_state(game_ui
*ui
, game_state
*oldstate
,
1842 game_state
*newstate
)
1846 struct game_drawstate
{
1851 unsigned char *visible
;
1854 /* ----------------------------------------------------------------------
1857 static char *interpret_move(game_state
*state
, game_ui
*ui
,
1858 game_drawstate
*ds
, int x
, int y
, int button
)
1861 int tx
= -1, ty
= -1, dir
= 0;
1862 int shift
= button
& MOD_SHFT
, ctrl
= button
& MOD_CTRL
;
1864 NONE
, ROTATE_LEFT
, ROTATE_180
, ROTATE_RIGHT
, TOGGLE_LOCK
, JUMBLE
,
1865 MOVE_ORIGIN
, MOVE_SOURCE
, MOVE_ORIGIN_AND_SOURCE
, MOVE_CURSOR
1868 button
&= ~MOD_MASK
;
1872 if (button
== LEFT_BUTTON
||
1873 button
== MIDDLE_BUTTON
||
1874 button
== RIGHT_BUTTON
) {
1876 if (ui
->cur_visible
) {
1877 ui
->cur_visible
= FALSE
;
1882 * The button must have been clicked on a valid tile.
1884 x
-= WINDOW_OFFSET
+ TILE_BORDER
;
1885 y
-= WINDOW_OFFSET
+ TILE_BORDER
;
1890 if (tx
>= state
->width
|| ty
>= state
->height
)
1892 /* Transform from physical to game coords */
1893 tx
= (tx
+ ui
->org_x
) % state
->width
;
1894 ty
= (ty
+ ui
->org_y
) % state
->height
;
1895 if (x
% TILE_SIZE
>= TILE_SIZE
- TILE_BORDER
||
1896 y
% TILE_SIZE
>= TILE_SIZE
- TILE_BORDER
)
1899 action
= button
== LEFT_BUTTON ? ROTATE_LEFT
:
1900 button
== RIGHT_BUTTON ? ROTATE_RIGHT
: TOGGLE_LOCK
;
1901 } else if (button
== CURSOR_UP
|| button
== CURSOR_DOWN
||
1902 button
== CURSOR_RIGHT
|| button
== CURSOR_LEFT
) {
1904 case CURSOR_UP
: dir
= U
; break;
1905 case CURSOR_DOWN
: dir
= D
; break;
1906 case CURSOR_LEFT
: dir
= L
; break;
1907 case CURSOR_RIGHT
: dir
= R
; break;
1908 default: return nullret
;
1910 if (shift
&& ctrl
) action
= MOVE_ORIGIN_AND_SOURCE
;
1911 else if (shift
) action
= MOVE_ORIGIN
;
1912 else if (ctrl
) action
= MOVE_SOURCE
;
1913 else action
= MOVE_CURSOR
;
1914 } else if (button
== 'a' || button
== 's' || button
== 'd' ||
1915 button
== 'A' || button
== 'S' || button
== 'D' ||
1916 button
== 'f' || button
== 'F' ||
1917 button
== CURSOR_SELECT
) {
1920 if (button
== 'a' || button
== 'A' || button
== CURSOR_SELECT
)
1921 action
= ROTATE_LEFT
;
1922 else if (button
== 's' || button
== 'S')
1923 action
= TOGGLE_LOCK
;
1924 else if (button
== 'd' || button
== 'D')
1925 action
= ROTATE_RIGHT
;
1926 else if (button
== 'f' || button
== 'F')
1927 action
= ROTATE_180
;
1928 ui
->cur_visible
= TRUE
;
1929 } else if (button
== 'j' || button
== 'J') {
1930 /* XXX should we have some mouse control for this? */
1936 * The middle button locks or unlocks a tile. (A locked tile
1937 * cannot be turned, and is visually marked as being locked.
1938 * This is a convenience for the player, so that once they are
1939 * sure which way round a tile goes, they can lock it and thus
1940 * avoid forgetting later on that they'd already done that one;
1941 * and the locking also prevents them turning the tile by
1942 * accident. If they change their mind, another middle click
1945 if (action
== TOGGLE_LOCK
) {
1947 sprintf(buf
, "L%d,%d", tx
, ty
);
1949 } else if (action
== ROTATE_LEFT
|| action
== ROTATE_RIGHT
||
1950 action
== ROTATE_180
) {
1954 * The left and right buttons have no effect if clicked on a
1957 if (tile(state
, tx
, ty
) & LOCKED
)
1961 * Otherwise, turn the tile one way or the other. Left button
1962 * turns anticlockwise; right button turns clockwise.
1964 sprintf(buf
, "%c%d,%d", (int)(action
== ROTATE_LEFT ?
'A' :
1965 action
== ROTATE_RIGHT ?
'C' : 'F'), tx
, ty
);
1967 } else if (action
== JUMBLE
) {
1969 * Jumble all unlocked tiles to random orientations.
1976 * Maximum string length assumes no int can be converted to
1977 * decimal and take more than 11 digits!
1979 maxlen
= state
->width
* state
->height
* 25 + 3;
1981 ret
= snewn(maxlen
, char);
1985 for (jy
= 0; jy
< state
->height
; jy
++) {
1986 for (jx
= 0; jx
< state
->width
; jx
++) {
1987 if (!(tile(state
, jx
, jy
) & LOCKED
)) {
1988 int rot
= random_upto(ui
->rs
, 4);
1990 p
+= sprintf(p
, ";%c%d,%d", "AFC"[rot
-1], jx
, jy
);
1996 assert(p
- ret
< maxlen
);
1997 ret
= sresize(ret
, p
- ret
, char);
2000 } else if (action
== MOVE_ORIGIN
|| action
== MOVE_SOURCE
||
2001 action
== MOVE_ORIGIN_AND_SOURCE
|| action
== MOVE_CURSOR
) {
2003 if (action
== MOVE_ORIGIN
|| action
== MOVE_ORIGIN_AND_SOURCE
) {
2004 if (state
->wrapping
) {
2005 OFFSET(ui
->org_x
, ui
->org_y
, ui
->org_x
, ui
->org_y
, dir
, state
);
2006 } else return nullret
; /* disallowed for non-wrapping grids */
2008 if (action
== MOVE_SOURCE
|| action
== MOVE_ORIGIN_AND_SOURCE
) {
2009 OFFSET(ui
->cx
, ui
->cy
, ui
->cx
, ui
->cy
, dir
, state
);
2011 if (action
== MOVE_CURSOR
) {
2012 OFFSET(ui
->cur_x
, ui
->cur_y
, ui
->cur_x
, ui
->cur_y
, dir
, state
);
2013 ui
->cur_visible
= TRUE
;
2021 static game_state
*execute_move(game_state
*from
, char *move
)
2024 int tx
, ty
, n
, noanim
, orig
;
2026 ret
= dup_game(from
);
2028 if (move
[0] == 'J' || move
[0] == 'S') {
2030 ret
->used_solve
= TRUE
;
2039 ret
->last_rotate_dir
= 0; /* suppress animation */
2040 ret
->last_rotate_x
= ret
->last_rotate_y
= 0;
2043 if ((move
[0] == 'A' || move
[0] == 'C' ||
2044 move
[0] == 'F' || move
[0] == 'L') &&
2045 sscanf(move
+1, "%d,%d%n", &tx
, &ty
, &n
) >= 2 &&
2046 tx
>= 0 && tx
< from
->width
&& ty
>= 0 && ty
< from
->height
) {
2047 orig
= tile(ret
, tx
, ty
);
2048 if (move
[0] == 'A') {
2049 tile(ret
, tx
, ty
) = A(orig
);
2051 ret
->last_rotate_dir
= +1;
2052 } else if (move
[0] == 'F') {
2053 tile(ret
, tx
, ty
) = F(orig
);
2055 ret
->last_rotate_dir
= +2; /* + for sake of argument */
2056 } else if (move
[0] == 'C') {
2057 tile(ret
, tx
, ty
) = C(orig
);
2059 ret
->last_rotate_dir
= -1;
2061 assert(move
[0] == 'L');
2062 tile(ret
, tx
, ty
) ^= LOCKED
;
2066 if (*move
== ';') move
++;
2073 ret
->last_rotate_x
= tx
;
2074 ret
->last_rotate_y
= ty
;
2078 * Check whether the game has been completed.
2080 * For this purpose it doesn't matter where the source square
2081 * is, because we can start from anywhere and correctly
2082 * determine whether the game is completed.
2085 unsigned char *active
= compute_active(ret
, 0, 0);
2087 int complete
= TRUE
;
2089 for (x1
= 0; x1
< ret
->width
; x1
++)
2090 for (y1
= 0; y1
< ret
->height
; y1
++)
2091 if ((tile(ret
, x1
, y1
) & 0xF) && !index(ret
, active
, x1
, y1
)) {
2093 goto break_label
; /* break out of two loops at once */
2100 ret
->completed
= TRUE
;
2107 /* ----------------------------------------------------------------------
2108 * Routines for drawing the game position on the screen.
2111 static game_drawstate
*game_new_drawstate(drawing
*dr
, game_state
*state
)
2113 game_drawstate
*ds
= snew(game_drawstate
);
2115 ds
->started
= FALSE
;
2116 ds
->width
= state
->width
;
2117 ds
->height
= state
->height
;
2118 ds
->org_x
= ds
->org_y
= -1;
2119 ds
->visible
= snewn(state
->width
* state
->height
, unsigned char);
2120 ds
->tilesize
= 0; /* undecided yet */
2121 memset(ds
->visible
, 0xFF, state
->width
* state
->height
);
2126 static void game_free_drawstate(drawing
*dr
, game_drawstate
*ds
)
2132 static void game_compute_size(game_params
*params
, int tilesize
,
2135 *x
= WINDOW_OFFSET
* 2 + tilesize
* params
->width
+ TILE_BORDER
;
2136 *y
= WINDOW_OFFSET
* 2 + tilesize
* params
->height
+ TILE_BORDER
;
2139 static void game_set_size(drawing
*dr
, game_drawstate
*ds
,
2140 game_params
*params
, int tilesize
)
2142 ds
->tilesize
= tilesize
;
2145 static float *game_colours(frontend
*fe
, int *ncolours
)
2149 ret
= snewn(NCOLOURS
* 3, float);
2150 *ncolours
= NCOLOURS
;
2153 * Basic background colour is whatever the front end thinks is
2154 * a sensible default.
2156 frontend_default_colour(fe
, &ret
[COL_BACKGROUND
* 3]);
2161 ret
[COL_WIRE
* 3 + 0] = 0.0F
;
2162 ret
[COL_WIRE
* 3 + 1] = 0.0F
;
2163 ret
[COL_WIRE
* 3 + 2] = 0.0F
;
2166 * Powered wires and powered endpoints are cyan.
2168 ret
[COL_POWERED
* 3 + 0] = 0.0F
;
2169 ret
[COL_POWERED
* 3 + 1] = 1.0F
;
2170 ret
[COL_POWERED
* 3 + 2] = 1.0F
;
2175 ret
[COL_BARRIER
* 3 + 0] = 1.0F
;
2176 ret
[COL_BARRIER
* 3 + 1] = 0.0F
;
2177 ret
[COL_BARRIER
* 3 + 2] = 0.0F
;
2180 * Unpowered endpoints are blue.
2182 ret
[COL_ENDPOINT
* 3 + 0] = 0.0F
;
2183 ret
[COL_ENDPOINT
* 3 + 1] = 0.0F
;
2184 ret
[COL_ENDPOINT
* 3 + 2] = 1.0F
;
2187 * Tile borders are a darker grey than the background.
2189 ret
[COL_BORDER
* 3 + 0] = 0.5F
* ret
[COL_BACKGROUND
* 3 + 0];
2190 ret
[COL_BORDER
* 3 + 1] = 0.5F
* ret
[COL_BACKGROUND
* 3 + 1];
2191 ret
[COL_BORDER
* 3 + 2] = 0.5F
* ret
[COL_BACKGROUND
* 3 + 2];
2194 * Locked tiles are a grey in between those two.
2196 ret
[COL_LOCKED
* 3 + 0] = 0.75F
* ret
[COL_BACKGROUND
* 3 + 0];
2197 ret
[COL_LOCKED
* 3 + 1] = 0.75F
* ret
[COL_BACKGROUND
* 3 + 1];
2198 ret
[COL_LOCKED
* 3 + 2] = 0.75F
* ret
[COL_BACKGROUND
* 3 + 2];
2203 static void draw_thick_line(drawing
*dr
, int x1
, int y1
, int x2
, int y2
,
2206 draw_line(dr
, x1
-1, y1
, x2
-1, y2
, COL_WIRE
);
2207 draw_line(dr
, x1
+1, y1
, x2
+1, y2
, COL_WIRE
);
2208 draw_line(dr
, x1
, y1
-1, x2
, y2
-1, COL_WIRE
);
2209 draw_line(dr
, x1
, y1
+1, x2
, y2
+1, COL_WIRE
);
2210 draw_line(dr
, x1
, y1
, x2
, y2
, colour
);
2213 static void draw_rect_coords(drawing
*dr
, int x1
, int y1
, int x2
, int y2
,
2216 int mx
= (x1
< x2 ? x1
: x2
);
2217 int my
= (y1
< y2 ? y1
: y2
);
2218 int dx
= (x2
+ x1
- 2*mx
+ 1);
2219 int dy
= (y2
+ y1
- 2*my
+ 1);
2221 draw_rect(dr
, mx
, my
, dx
, dy
, colour
);
2225 * draw_barrier_corner() and draw_barrier() are passed physical coords
2227 static void draw_barrier_corner(drawing
*dr
, game_drawstate
*ds
,
2228 int x
, int y
, int dx
, int dy
, int phase
)
2230 int bx
= WINDOW_OFFSET
+ TILE_SIZE
* x
;
2231 int by
= WINDOW_OFFSET
+ TILE_SIZE
* y
;
2234 x1
= (dx
> 0 ? TILE_SIZE
+TILE_BORDER
-1 : 0);
2235 y1
= (dy
> 0 ? TILE_SIZE
+TILE_BORDER
-1 : 0);
2238 draw_rect_coords(dr
, bx
+x1
+dx
, by
+y1
,
2239 bx
+x1
-TILE_BORDER
*dx
, by
+y1
-(TILE_BORDER
-1)*dy
,
2241 draw_rect_coords(dr
, bx
+x1
, by
+y1
+dy
,
2242 bx
+x1
-(TILE_BORDER
-1)*dx
, by
+y1
-TILE_BORDER
*dy
,
2245 draw_rect_coords(dr
, bx
+x1
, by
+y1
,
2246 bx
+x1
-(TILE_BORDER
-1)*dx
, by
+y1
-(TILE_BORDER
-1)*dy
,
2251 static void draw_barrier(drawing
*dr
, game_drawstate
*ds
,
2252 int x
, int y
, int dir
, int phase
)
2254 int bx
= WINDOW_OFFSET
+ TILE_SIZE
* x
;
2255 int by
= WINDOW_OFFSET
+ TILE_SIZE
* y
;
2258 x1
= (X(dir
) > 0 ? TILE_SIZE
: X(dir
) == 0 ? TILE_BORDER
: 0);
2259 y1
= (Y(dir
) > 0 ? TILE_SIZE
: Y(dir
) == 0 ? TILE_BORDER
: 0);
2260 w
= (X(dir
) ? TILE_BORDER
: TILE_SIZE
- TILE_BORDER
);
2261 h
= (Y(dir
) ? TILE_BORDER
: TILE_SIZE
- TILE_BORDER
);
2264 draw_rect(dr
, bx
+x1
-X(dir
), by
+y1
-Y(dir
), w
, h
, COL_WIRE
);
2266 draw_rect(dr
, bx
+x1
, by
+y1
, w
, h
, COL_BARRIER
);
2271 * draw_tile() is passed physical coordinates
2273 static void draw_tile(drawing
*dr
, game_state
*state
, game_drawstate
*ds
,
2274 int x
, int y
, int tile
, int src
, float angle
, int cursor
)
2276 int bx
= WINDOW_OFFSET
+ TILE_SIZE
* x
;
2277 int by
= WINDOW_OFFSET
+ TILE_SIZE
* y
;
2279 float cx
, cy
, ex
, ey
, tx
, ty
;
2280 int dir
, col
, phase
;
2283 * When we draw a single tile, we must draw everything up to
2284 * and including the borders around the tile. This means that
2285 * if the neighbouring tiles have connections to those borders,
2286 * we must draw those connections on the borders themselves.
2289 clip(dr
, bx
, by
, TILE_SIZE
+TILE_BORDER
, TILE_SIZE
+TILE_BORDER
);
2292 * So. First blank the tile out completely: draw a big
2293 * rectangle in border colour, and a smaller rectangle in
2294 * background colour to fill it in.
2296 draw_rect(dr
, bx
, by
, TILE_SIZE
+TILE_BORDER
, TILE_SIZE
+TILE_BORDER
,
2298 draw_rect(dr
, bx
+TILE_BORDER
, by
+TILE_BORDER
,
2299 TILE_SIZE
-TILE_BORDER
, TILE_SIZE
-TILE_BORDER
,
2300 tile
& LOCKED ? COL_LOCKED
: COL_BACKGROUND
);
2303 * Draw an inset outline rectangle as a cursor, in whichever of
2304 * COL_LOCKED and COL_BACKGROUND we aren't currently drawing
2308 draw_line(dr
, bx
+TILE_SIZE
/8, by
+TILE_SIZE
/8,
2309 bx
+TILE_SIZE
/8, by
+TILE_SIZE
-TILE_SIZE
/8,
2310 tile
& LOCKED ? COL_BACKGROUND
: COL_LOCKED
);
2311 draw_line(dr
, bx
+TILE_SIZE
/8, by
+TILE_SIZE
/8,
2312 bx
+TILE_SIZE
-TILE_SIZE
/8, by
+TILE_SIZE
/8,
2313 tile
& LOCKED ? COL_BACKGROUND
: COL_LOCKED
);
2314 draw_line(dr
, bx
+TILE_SIZE
-TILE_SIZE
/8, by
+TILE_SIZE
/8,
2315 bx
+TILE_SIZE
-TILE_SIZE
/8, by
+TILE_SIZE
-TILE_SIZE
/8,
2316 tile
& LOCKED ? COL_BACKGROUND
: COL_LOCKED
);
2317 draw_line(dr
, bx
+TILE_SIZE
/8, by
+TILE_SIZE
-TILE_SIZE
/8,
2318 bx
+TILE_SIZE
-TILE_SIZE
/8, by
+TILE_SIZE
-TILE_SIZE
/8,
2319 tile
& LOCKED ? COL_BACKGROUND
: COL_LOCKED
);
2323 * Set up the rotation matrix.
2325 matrix
[0] = (float)cos(angle
* PI
/ 180.0);
2326 matrix
[1] = (float)-sin(angle
* PI
/ 180.0);
2327 matrix
[2] = (float)sin(angle
* PI
/ 180.0);
2328 matrix
[3] = (float)cos(angle
* PI
/ 180.0);
2333 cx
= cy
= TILE_BORDER
+ (TILE_SIZE
-TILE_BORDER
) / 2.0F
- 0.5F
;
2334 col
= (tile
& ACTIVE ? COL_POWERED
: COL_WIRE
);
2335 for (dir
= 1; dir
< 0x10; dir
<<= 1) {
2337 ex
= (TILE_SIZE
- TILE_BORDER
- 1.0F
) / 2.0F
* X(dir
);
2338 ey
= (TILE_SIZE
- TILE_BORDER
- 1.0F
) / 2.0F
* Y(dir
);
2339 MATMUL(tx
, ty
, matrix
, ex
, ey
);
2340 draw_thick_line(dr
, bx
+(int)cx
, by
+(int)cy
,
2341 bx
+(int)(cx
+tx
), by
+(int)(cy
+ty
),
2345 for (dir
= 1; dir
< 0x10; dir
<<= 1) {
2347 ex
= (TILE_SIZE
- TILE_BORDER
- 1.0F
) / 2.0F
* X(dir
);
2348 ey
= (TILE_SIZE
- TILE_BORDER
- 1.0F
) / 2.0F
* Y(dir
);
2349 MATMUL(tx
, ty
, matrix
, ex
, ey
);
2350 draw_line(dr
, bx
+(int)cx
, by
+(int)cy
,
2351 bx
+(int)(cx
+tx
), by
+(int)(cy
+ty
), col
);
2356 * Draw the box in the middle. We do this in blue if the tile
2357 * is an unpowered endpoint, in cyan if the tile is a powered
2358 * endpoint, in black if the tile is the centrepiece, and
2359 * otherwise not at all.
2364 else if (COUNT(tile
) == 1) {
2365 col
= (tile
& ACTIVE ? COL_POWERED
: COL_ENDPOINT
);
2370 points
[0] = +1; points
[1] = +1;
2371 points
[2] = +1; points
[3] = -1;
2372 points
[4] = -1; points
[5] = -1;
2373 points
[6] = -1; points
[7] = +1;
2375 for (i
= 0; i
< 8; i
+= 2) {
2376 ex
= (TILE_SIZE
* 0.24F
) * points
[i
];
2377 ey
= (TILE_SIZE
* 0.24F
) * points
[i
+1];
2378 MATMUL(tx
, ty
, matrix
, ex
, ey
);
2379 points
[i
] = bx
+(int)(cx
+tx
);
2380 points
[i
+1] = by
+(int)(cy
+ty
);
2383 draw_polygon(dr
, points
, 4, col
, COL_WIRE
);
2387 * Draw the points on the border if other tiles are connected
2390 for (dir
= 1; dir
< 0x10; dir
<<= 1) {
2391 int dx
, dy
, px
, py
, lx
, ly
, vx
, vy
, ox
, oy
;
2399 if (ox
< 0 || ox
>= state
->width
|| oy
< 0 || oy
>= state
->height
)
2402 if (!(tile(state
, GX(ox
), GY(oy
)) & F(dir
)))
2405 px
= bx
+ (int)(dx
>0 ? TILE_SIZE
+ TILE_BORDER
- 1 : dx
<0 ?
0 : cx
);
2406 py
= by
+ (int)(dy
>0 ? TILE_SIZE
+ TILE_BORDER
- 1 : dy
<0 ?
0 : cy
);
2407 lx
= dx
* (TILE_BORDER
-1);
2408 ly
= dy
* (TILE_BORDER
-1);
2412 if (angle
== 0.0 && (tile
& dir
)) {
2414 * If we are fully connected to the other tile, we must
2415 * draw right across the tile border. (We can use our
2416 * own ACTIVE state to determine what colour to do this
2417 * in: if we are fully connected to the other tile then
2418 * the two ACTIVE states will be the same.)
2420 draw_rect_coords(dr
, px
-vx
, py
-vy
, px
+lx
+vx
, py
+ly
+vy
, COL_WIRE
);
2421 draw_rect_coords(dr
, px
, py
, px
+lx
, py
+ly
,
2422 (tile
& ACTIVE
) ? COL_POWERED
: COL_WIRE
);
2425 * The other tile extends into our border, but isn't
2426 * actually connected to us. Just draw a single black
2429 draw_rect_coords(dr
, px
, py
, px
, py
, COL_WIRE
);
2434 * Draw barrier corners, and then barriers.
2436 for (phase
= 0; phase
< 2; phase
++) {
2437 for (dir
= 1; dir
< 0x10; dir
<<= 1) {
2438 int x1
, y1
, corner
= FALSE
;
2440 * If at least one barrier terminates at the corner
2441 * between dir and A(dir), draw a barrier corner.
2443 if (barrier(state
, GX(x
), GY(y
)) & (dir
| A(dir
))) {
2447 * Only count barriers terminating at this corner
2448 * if they're physically next to the corner. (That
2449 * is, if they've wrapped round from the far side
2450 * of the screen, they don't count.)
2454 if (x1
>= 0 && x1
< state
->width
&&
2455 y1
>= 0 && y1
< state
->height
&&
2456 (barrier(state
, GX(x1
), GY(y1
)) & A(dir
))) {
2461 if (x1
>= 0 && x1
< state
->width
&&
2462 y1
>= 0 && y1
< state
->height
&&
2463 (barrier(state
, GX(x1
), GY(y1
)) & dir
))
2470 * At least one barrier terminates here. Draw a
2473 draw_barrier_corner(dr
, ds
, x
, y
,
2474 X(dir
)+X(A(dir
)), Y(dir
)+Y(A(dir
)),
2479 for (dir
= 1; dir
< 0x10; dir
<<= 1)
2480 if (barrier(state
, GX(x
), GY(y
)) & dir
)
2481 draw_barrier(dr
, ds
, x
, y
, dir
, phase
);
2486 draw_update(dr
, bx
, by
, TILE_SIZE
+TILE_BORDER
, TILE_SIZE
+TILE_BORDER
);
2489 static void game_redraw(drawing
*dr
, game_drawstate
*ds
, game_state
*oldstate
,
2490 game_state
*state
, int dir
, game_ui
*ui
, float t
, float ft
)
2492 int x
, y
, tx
, ty
, frame
, last_rotate_dir
, moved_origin
= FALSE
;
2493 unsigned char *active
;
2497 * Clear the screen, and draw the exterior barrier lines, if
2498 * this is our first call or if the origin has changed.
2500 if (!ds
->started
|| ui
->org_x
!= ds
->org_x
|| ui
->org_y
!= ds
->org_y
) {
2506 WINDOW_OFFSET
* 2 + TILE_SIZE
* state
->width
+ TILE_BORDER
,
2507 WINDOW_OFFSET
* 2 + TILE_SIZE
* state
->height
+ TILE_BORDER
,
2510 ds
->org_x
= ui
->org_x
;
2511 ds
->org_y
= ui
->org_y
;
2512 moved_origin
= TRUE
;
2514 draw_update(dr
, 0, 0,
2515 WINDOW_OFFSET
*2 + TILE_SIZE
*state
->width
+ TILE_BORDER
,
2516 WINDOW_OFFSET
*2 + TILE_SIZE
*state
->height
+ TILE_BORDER
);
2518 for (phase
= 0; phase
< 2; phase
++) {
2520 for (x
= 0; x
< ds
->width
; x
++) {
2521 if (x
+1 < ds
->width
) {
2522 if (barrier(state
, GX(x
), GY(0)) & R
)
2523 draw_barrier_corner(dr
, ds
, x
, -1, +1, +1, phase
);
2524 if (barrier(state
, GX(x
), GY(ds
->height
-1)) & R
)
2525 draw_barrier_corner(dr
, ds
, x
, ds
->height
, +1, -1, phase
);
2527 if (barrier(state
, GX(x
), GY(0)) & U
) {
2528 draw_barrier_corner(dr
, ds
, x
, -1, -1, +1, phase
);
2529 draw_barrier_corner(dr
, ds
, x
, -1, +1, +1, phase
);
2530 draw_barrier(dr
, ds
, x
, -1, D
, phase
);
2532 if (barrier(state
, GX(x
), GY(ds
->height
-1)) & D
) {
2533 draw_barrier_corner(dr
, ds
, x
, ds
->height
, -1, -1, phase
);
2534 draw_barrier_corner(dr
, ds
, x
, ds
->height
, +1, -1, phase
);
2535 draw_barrier(dr
, ds
, x
, ds
->height
, U
, phase
);
2539 for (y
= 0; y
< ds
->height
; y
++) {
2540 if (y
+1 < ds
->height
) {
2541 if (barrier(state
, GX(0), GY(y
)) & D
)
2542 draw_barrier_corner(dr
, ds
, -1, y
, +1, +1, phase
);
2543 if (barrier(state
, GX(ds
->width
-1), GY(y
)) & D
)
2544 draw_barrier_corner(dr
, ds
, ds
->width
, y
, -1, +1, phase
);
2546 if (barrier(state
, GX(0), GY(y
)) & L
) {
2547 draw_barrier_corner(dr
, ds
, -1, y
, +1, -1, phase
);
2548 draw_barrier_corner(dr
, ds
, -1, y
, +1, +1, phase
);
2549 draw_barrier(dr
, ds
, -1, y
, R
, phase
);
2551 if (barrier(state
, GX(ds
->width
-1), GY(y
)) & R
) {
2552 draw_barrier_corner(dr
, ds
, ds
->width
, y
, -1, -1, phase
);
2553 draw_barrier_corner(dr
, ds
, ds
->width
, y
, -1, +1, phase
);
2554 draw_barrier(dr
, ds
, ds
->width
, y
, L
, phase
);
2561 last_rotate_dir
= dir
==-1 ? oldstate
->last_rotate_dir
:
2562 state
->last_rotate_dir
;
2563 if (oldstate
&& (t
< ROTATE_TIME
) && last_rotate_dir
) {
2565 * We're animating a single tile rotation. Find the turning
2568 tx
= (dir
==-1 ? oldstate
->last_rotate_x
: state
->last_rotate_x
);
2569 ty
= (dir
==-1 ? oldstate
->last_rotate_y
: state
->last_rotate_y
);
2570 angle
= last_rotate_dir
* dir
* 90.0F
* (t
/ ROTATE_TIME
);
2577 * We're animating a completion flash. Find which frame
2580 frame
= (int)(ft
/ FLASH_FRAME
);
2584 * Draw any tile which differs from the way it was last drawn.
2586 active
= compute_active(state
, ui
->cx
, ui
->cy
);
2588 for (x
= 0; x
< ds
->width
; x
++)
2589 for (y
= 0; y
< ds
->height
; y
++) {
2590 unsigned char c
= tile(state
, GX(x
), GY(y
)) |
2591 index(state
, active
, GX(x
), GY(y
));
2592 int is_src
= GX(x
) == ui
->cx
&& GY(y
) == ui
->cy
;
2593 int is_anim
= GX(x
) == tx
&& GY(y
) == ty
;
2594 int is_cursor
= ui
->cur_visible
&&
2595 GX(x
) == ui
->cur_x
&& GY(y
) == ui
->cur_y
;
2598 * In a completion flash, we adjust the LOCKED bit
2599 * depending on our distance from the centre point and
2603 int rcx
= RX(ui
->cx
), rcy
= RY(ui
->cy
);
2604 int xdist
, ydist
, dist
;
2605 xdist
= (x
< rcx ? rcx
- x
: x
- rcx
);
2606 ydist
= (y
< rcy ? rcy
- y
: y
- rcy
);
2607 dist
= (xdist
> ydist ? xdist
: ydist
);
2609 if (frame
>= dist
&& frame
< dist
+4) {
2610 int lock
= (frame
- dist
) & 1;
2611 lock
= lock ? LOCKED
: 0;
2612 c
= (c
&~ LOCKED
) | lock
;
2617 index(state
, ds
->visible
, x
, y
) != c
||
2618 index(state
, ds
->visible
, x
, y
) == 0xFF ||
2619 is_src
|| is_anim
|| is_cursor
) {
2620 draw_tile(dr
, state
, ds
, x
, y
, c
,
2621 is_src
, (is_anim ? angle
: 0.0F
), is_cursor
);
2622 if (is_src
|| is_anim
|| is_cursor
)
2623 index(state
, ds
->visible
, x
, y
) = 0xFF;
2625 index(state
, ds
->visible
, x
, y
) = c
;
2630 * Update the status bar.
2633 char statusbuf
[256];
2636 n
= state
->width
* state
->height
;
2637 for (i
= a
= n2
= 0; i
< n
; i
++) {
2640 if (state
->tiles
[i
] & 0xF)
2644 sprintf(statusbuf
, "%sActive: %d/%d",
2645 (state
->used_solve ?
"Auto-solved. " :
2646 state
->completed ?
"COMPLETED! " : ""), a
, n2
);
2648 status_bar(dr
, statusbuf
);
2654 static float game_anim_length(game_state
*oldstate
,
2655 game_state
*newstate
, int dir
, game_ui
*ui
)
2657 int last_rotate_dir
;
2660 * Don't animate if last_rotate_dir is zero.
2662 last_rotate_dir
= dir
==-1 ? oldstate
->last_rotate_dir
:
2663 newstate
->last_rotate_dir
;
2664 if (last_rotate_dir
)
2670 static float game_flash_length(game_state
*oldstate
,
2671 game_state
*newstate
, int dir
, game_ui
*ui
)
2674 * If the game has just been completed, we display a completion
2677 if (!oldstate
->completed
&& newstate
->completed
&&
2678 !oldstate
->used_solve
&& !newstate
->used_solve
) {
2680 if (size
< newstate
->width
)
2681 size
= newstate
->width
;
2682 if (size
< newstate
->height
)
2683 size
= newstate
->height
;
2684 return FLASH_FRAME
* (size
+4);
2690 static int game_timing_state(game_state
*state
, game_ui
*ui
)
2695 static void game_print_size(game_params
*params
, float *x
, float *y
)
2700 * I'll use 8mm squares by default.
2702 game_compute_size(params
, 800, &pw
, &ph
);
2707 static void draw_diagram(drawing
*dr
, game_drawstate
*ds
, int x
, int y
,
2708 int topleft
, int v
, int drawlines
, int ink
)
2710 int tx
, ty
, cx
, cy
, r
, br
, k
, thick
;
2712 tx
= WINDOW_OFFSET
+ TILE_SIZE
* x
;
2713 ty
= WINDOW_OFFSET
+ TILE_SIZE
* y
;
2716 * Find our centre point.
2719 cx
= tx
+ (v
& L ? TILE_SIZE
/ 4 : TILE_SIZE
/ 6);
2720 cy
= ty
+ (v
& U ? TILE_SIZE
/ 4 : TILE_SIZE
/ 6);
2722 br
= TILE_SIZE
/ 32;
2724 cx
= tx
+ TILE_SIZE
/ 2;
2725 cy
= ty
+ TILE_SIZE
/ 2;
2732 * Draw the square block if we have an endpoint.
2734 if (v
== 1 || v
== 2 || v
== 4 || v
== 8)
2735 draw_rect(dr
, cx
- br
, cy
- br
, br
*2, br
*2, ink
);
2738 * Draw each radial line.
2741 for (k
= 1; k
< 16; k
*= 2)
2743 int x1
= min(cx
, cx
+ (r
-thick
) * X(k
));
2744 int x2
= max(cx
, cx
+ (r
-thick
) * X(k
));
2745 int y1
= min(cy
, cy
+ (r
-thick
) * Y(k
));
2746 int y2
= max(cy
, cy
+ (r
-thick
) * Y(k
));
2747 draw_rect(dr
, x1
- thick
, y1
- thick
,
2748 (x2
- x1
) + 2*thick
, (y2
- y1
) + 2*thick
, ink
);
2753 static void game_print(drawing
*dr
, game_state
*state
, int tilesize
)
2755 int w
= state
->width
, h
= state
->height
;
2756 int ink
= print_mono_colour(dr
, 0);
2759 /* Ick: fake up `ds->tilesize' for macro expansion purposes */
2760 game_drawstate ads
, *ds
= &ads
;
2761 game_set_size(dr
, ds
, NULL
, tilesize
);
2766 print_line_width(dr
, TILE_SIZE
/ (state
->wrapping ?
128 : 12));
2767 draw_rect_outline(dr
, WINDOW_OFFSET
, WINDOW_OFFSET
,
2768 TILE_SIZE
* w
, TILE_SIZE
* h
, ink
);
2773 print_line_width(dr
, TILE_SIZE
/ 128);
2774 for (x
= 1; x
< w
; x
++)
2775 draw_line(dr
, WINDOW_OFFSET
+ TILE_SIZE
* x
, WINDOW_OFFSET
,
2776 WINDOW_OFFSET
+ TILE_SIZE
* x
, WINDOW_OFFSET
+ TILE_SIZE
* h
,
2778 for (y
= 1; y
< h
; y
++)
2779 draw_line(dr
, WINDOW_OFFSET
, WINDOW_OFFSET
+ TILE_SIZE
* y
,
2780 WINDOW_OFFSET
+ TILE_SIZE
* w
, WINDOW_OFFSET
+ TILE_SIZE
* y
,
2786 for (y
= 0; y
<= h
; y
++)
2787 for (x
= 0; x
<= w
; x
++) {
2788 int b
= barrier(state
, x
% w
, y
% h
);
2789 if (x
< w
&& (b
& U
))
2790 draw_rect(dr
, WINDOW_OFFSET
+ TILE_SIZE
* x
- TILE_SIZE
/24,
2791 WINDOW_OFFSET
+ TILE_SIZE
* y
- TILE_SIZE
/24,
2792 TILE_SIZE
+ TILE_SIZE
/24 * 2, TILE_SIZE
/24 * 2, ink
);
2793 if (y
< h
&& (b
& L
))
2794 draw_rect(dr
, WINDOW_OFFSET
+ TILE_SIZE
* x
- TILE_SIZE
/24,
2795 WINDOW_OFFSET
+ TILE_SIZE
* y
- TILE_SIZE
/24,
2796 TILE_SIZE
/24 * 2, TILE_SIZE
+ TILE_SIZE
/24 * 2, ink
);
2802 for (y
= 0; y
< h
; y
++)
2803 for (x
= 0; x
< w
; x
++) {
2804 int vx
, v
= tile(state
, x
, y
);
2805 int locked
= v
& LOCKED
;
2810 * Rotate into a standard orientation for the top left
2814 while (vx
!= 0 && vx
!= 15 && vx
!= 1 && vx
!= 9 && vx
!= 13 &&
2819 * Draw the top left corner diagram.
2821 draw_diagram(dr
, ds
, x
, y
, TRUE
, vx
, TRUE
, ink
);
2824 * Draw the real solution diagram, if we're doing so.
2826 draw_diagram(dr
, ds
, x
, y
, FALSE
, v
, locked
, ink
);
2834 const struct game thegame
= {
2835 "Net", "games.net", "net",
2842 TRUE
, game_configure
, custom_params
,
2850 FALSE
, game_text_format
,
2858 PREFERRED_TILE_SIZE
, game_compute_size
, game_set_size
,
2861 game_free_drawstate
,
2865 TRUE
, FALSE
, game_print_size
, game_print
,
2866 TRUE
, /* wants_statusbar */
2867 FALSE
, game_timing_state
,