2 * map.c: Game involving four-colouring a map.
9 * - better four-colouring algorithm?
22 * In standalone solver mode, `verbose' is a variable which can be
23 * set by command-line option; in debugging mode it's simply always
26 #if defined STANDALONE_SOLVER
27 #define SOLVER_DIAGNOSTICS
29 #elif defined SOLVER_DIAGNOSTICS
34 * I don't seriously anticipate wanting to change the number of
35 * colours used in this game, but it doesn't cost much to use a
36 * #define just in case :-)
39 #define THREE (FOUR-1)
44 * Ghastly run-time configuration option, just for Gareth (again).
46 static int flash_type
= -1;
47 static float flash_length
;
50 * Difficulty levels. I do some macro ickery here to ensure that my
51 * enum and the various forms of my name list always match up.
57 A(RECURSE,Unreasonable,u)
58 #define ENUM(upper,title,lower) DIFF_ ## upper,
59 #define TITLE(upper,title,lower) #title,
60 #define ENCODE(upper,title,lower) #lower
61 #define CONFIG(upper,title,lower) ":" #title
62 enum { DIFFLIST(ENUM
) DIFFCOUNT
};
63 static char const *const map_diffnames
[] = { DIFFLIST(TITLE
) };
64 static char const map_diffchars
[] = DIFFLIST(ENCODE
);
65 #define DIFFCONFIG DIFFLIST(CONFIG)
67 enum { TE
, BE
, LE
, RE
}; /* top/bottom/left/right edges */
72 COL_0
, COL_1
, COL_2
, COL_3
,
73 COL_ERROR
, COL_ERRTEXT
,
88 int *edgex
, *edgey
; /* position of a point on each edge */
89 int *regionx
, *regiony
; /* position of a point in each region */
95 int *colouring
, *pencil
;
96 int completed
, cheated
;
99 static game_params
*default_params(void)
101 game_params
*ret
= snew(game_params
);
103 #ifdef PORTRAIT_SCREEN
111 ret
->diff
= DIFF_NORMAL
;
116 static const struct game_params map_presets
[] = {
117 #ifdef PORTRAIT_SCREEN
118 {16, 18, 30, DIFF_EASY
},
119 {16, 18, 30, DIFF_NORMAL
},
120 {16, 18, 30, DIFF_HARD
},
121 {16, 18, 30, DIFF_RECURSE
},
122 {25, 30, 75, DIFF_NORMAL
},
123 {25, 30, 75, DIFF_HARD
},
125 {20, 15, 30, DIFF_EASY
},
126 {20, 15, 30, DIFF_NORMAL
},
127 {20, 15, 30, DIFF_HARD
},
128 {20, 15, 30, DIFF_RECURSE
},
129 {30, 25, 75, DIFF_NORMAL
},
130 {30, 25, 75, DIFF_HARD
},
134 static int game_fetch_preset(int i
, char **name
, game_params
**params
)
139 if (i
< 0 || i
>= lenof(map_presets
))
142 ret
= snew(game_params
);
143 *ret
= map_presets
[i
];
145 sprintf(str
, "%dx%d, %d regions, %s", ret
->w
, ret
->h
, ret
->n
,
146 map_diffnames
[ret
->diff
]);
153 static void free_params(game_params
*params
)
158 static game_params
*dup_params(game_params
*params
)
160 game_params
*ret
= snew(game_params
);
161 *ret
= *params
; /* structure copy */
165 static void decode_params(game_params
*params
, char const *string
)
167 char const *p
= string
;
170 while (*p
&& isdigit((unsigned char)*p
)) p
++;
174 while (*p
&& isdigit((unsigned char)*p
)) p
++;
176 params
->h
= params
->w
;
181 while (*p
&& (*p
== '.' || isdigit((unsigned char)*p
))) p
++;
183 params
->n
= params
->w
* params
->h
/ 8;
188 for (i
= 0; i
< DIFFCOUNT
; i
++)
189 if (*p
== map_diffchars
[i
])
195 static char *encode_params(game_params
*params
, int full
)
199 sprintf(ret
, "%dx%dn%d", params
->w
, params
->h
, params
->n
);
201 sprintf(ret
+ strlen(ret
), "d%c", map_diffchars
[params
->diff
]);
206 static config_item
*game_configure(game_params
*params
)
211 ret
= snewn(5, config_item
);
213 ret
[0].name
= "Width";
214 ret
[0].type
= C_STRING
;
215 sprintf(buf
, "%d", params
->w
);
216 ret
[0].sval
= dupstr(buf
);
219 ret
[1].name
= "Height";
220 ret
[1].type
= C_STRING
;
221 sprintf(buf
, "%d", params
->h
);
222 ret
[1].sval
= dupstr(buf
);
225 ret
[2].name
= "Regions";
226 ret
[2].type
= C_STRING
;
227 sprintf(buf
, "%d", params
->n
);
228 ret
[2].sval
= dupstr(buf
);
231 ret
[3].name
= "Difficulty";
232 ret
[3].type
= C_CHOICES
;
233 ret
[3].sval
= DIFFCONFIG
;
234 ret
[3].ival
= params
->diff
;
244 static game_params
*custom_params(config_item
*cfg
)
246 game_params
*ret
= snew(game_params
);
248 ret
->w
= atoi(cfg
[0].sval
);
249 ret
->h
= atoi(cfg
[1].sval
);
250 ret
->n
= atoi(cfg
[2].sval
);
251 ret
->diff
= cfg
[3].ival
;
256 static char *validate_params(game_params
*params
, int full
)
258 if (params
->w
< 2 || params
->h
< 2)
259 return "Width and height must be at least two";
261 return "Must have at least five regions";
262 if (params
->n
> params
->w
* params
->h
)
263 return "Too many regions to fit in grid";
267 /* ----------------------------------------------------------------------
268 * Cumulative frequency table functions.
272 * Initialise a cumulative frequency table. (Hardly worth writing
273 * this function; all it does is to initialise everything in the
276 static void cf_init(int *table
, int n
)
280 for (i
= 0; i
< n
; i
++)
285 * Increment the count of symbol `sym' by `count'.
287 static void cf_add(int *table
, int n
, int sym
, int count
)
304 * Cumulative frequency lookup: return the total count of symbols
305 * with value less than `sym'.
307 static int cf_clookup(int *table
, int n
, int sym
)
309 int bit
, index
, limit
, count
;
314 assert(0 < sym
&& sym
<= n
);
316 count
= table
[0]; /* start with the whole table size */
326 * Find the least number with its lowest set bit in this
327 * position which is greater than or equal to sym.
329 index
= ((sym
+ bit
- 1) &~ (bit
* 2 - 1)) + bit
;
332 count
-= table
[index
];
343 * Single frequency lookup: return the count of symbol `sym'.
345 static int cf_slookup(int *table
, int n
, int sym
)
349 assert(0 <= sym
&& sym
< n
);
353 for (bit
= 1; sym
+bit
< n
&& !(sym
& bit
); bit
<<= 1)
354 count
-= table
[sym
+bit
];
360 * Return the largest symbol index such that the cumulative
361 * frequency up to that symbol is less than _or equal to_ count.
363 static int cf_whichsym(int *table
, int n
, int count
) {
366 assert(count
>= 0 && count
< table
[0]);
377 if (count
>= top
- table
[sym
+bit
])
380 top
-= table
[sym
+bit
];
389 /* ----------------------------------------------------------------------
392 * FIXME: this isn't entirely optimal at present, because it
393 * inherently prioritises growing the largest region since there
394 * are more squares adjacent to it. This acts as a destabilising
395 * influence leading to a few large regions and mostly small ones.
396 * It might be better to do it some other way.
399 #define WEIGHT_INCREASED 2 /* for increased perimeter */
400 #define WEIGHT_DECREASED 4 /* for decreased perimeter */
401 #define WEIGHT_UNCHANGED 3 /* for unchanged perimeter */
404 * Look at a square and decide which colours can be extended into
407 * If called with index < 0, it adds together one of
408 * WEIGHT_INCREASED, WEIGHT_DECREASED or WEIGHT_UNCHANGED for each
409 * colour that has a valid extension (according to the effect that
410 * it would have on the perimeter of the region being extended) and
411 * returns the overall total.
413 * If called with index >= 0, it returns one of the possible
414 * colours depending on the value of index, in such a way that the
415 * number of possible inputs which would give rise to a given
416 * return value correspond to the weight of that value.
418 static int extend_options(int w
, int h
, int n
, int *map
,
419 int x
, int y
, int index
)
425 if (map
[y
*w
+x
] >= 0) {
427 return 0; /* can't do this square at all */
431 * Fetch the eight neighbours of this square, in order around
434 for (dy
= -1; dy
<= +1; dy
++)
435 for (dx
= -1; dx
<= +1; dx
++) {
436 int index
= (dy
< 0 ?
6-dx
: dy
> 0 ?
2+dx
: 2*(1+dx
));
437 if (x
+dx
>= 0 && x
+dx
< w
&& y
+dy
>= 0 && y
+dy
< h
)
438 col
[index
] = map
[(y
+dy
)*w
+(x
+dx
)];
444 * Iterate over each colour that might be feasible.
446 * FIXME: this routine currently has O(n) running time. We
447 * could turn it into O(FOUR) by only bothering to iterate over
448 * the colours mentioned in the four neighbouring squares.
451 for (c
= 0; c
< n
; c
++) {
452 int count
, neighbours
, runs
;
455 * One of the even indices of col (representing the
456 * orthogonal neighbours of this square) must be equal to
457 * c, or else this square is not adjacent to region c and
458 * obviously cannot become an extension of it at this time.
461 for (i
= 0; i
< 8; i
+= 2)
468 * Now we know this square is adjacent to region c. The
469 * next question is, would extending it cause the region to
470 * become non-simply-connected? If so, we mustn't do it.
472 * We determine this by looking around col to see if we can
473 * find more than one separate run of colour c.
476 for (i
= 0; i
< 8; i
++)
477 if (col
[i
] == c
&& col
[(i
+1) & 7] != c
)
485 * This square is a possibility. Determine its effect on
486 * the region's perimeter (computed from the number of
487 * orthogonal neighbours - 1 means a perimeter increase, 3
488 * a decrease, 2 no change; 4 is impossible because the
489 * region would already not be simply connected) and we're
492 assert(neighbours
> 0 && neighbours
< 4);
493 count
= (neighbours
== 1 ? WEIGHT_INCREASED
:
494 neighbours
== 2 ? WEIGHT_UNCHANGED
: WEIGHT_DECREASED
);
497 if (index
>= 0 && index
< count
)
508 static void genmap(int w
, int h
, int n
, int *map
, random_state
*rs
)
515 tmp
= snewn(wh
, int);
518 * Clear the map, and set up `tmp' as a list of grid indices.
520 for (i
= 0; i
< wh
; i
++) {
526 * Place the region seeds by selecting n members from `tmp'.
529 for (i
= 0; i
< n
; i
++) {
530 int j
= random_upto(rs
, k
);
536 * Re-initialise `tmp' as a cumulative frequency table. This
537 * will store the number of possible region colours we can
538 * extend into each square.
543 * Go through the grid and set up the initial cumulative
546 for (y
= 0; y
< h
; y
++)
547 for (x
= 0; x
< w
; x
++)
548 cf_add(tmp
, wh
, y
*w
+x
,
549 extend_options(w
, h
, n
, map
, x
, y
, -1));
552 * Now repeatedly choose a square we can extend a region into,
556 int k
= random_upto(rs
, tmp
[0]);
561 sq
= cf_whichsym(tmp
, wh
, k
);
562 k
-= cf_clookup(tmp
, wh
, sq
);
565 colour
= extend_options(w
, h
, n
, map
, x
, y
, k
);
570 * Re-scan the nine cells around the one we've just
573 for (yy
= max(y
-1, 0); yy
< min(y
+2, h
); yy
++)
574 for (xx
= max(x
-1, 0); xx
< min(x
+2, w
); xx
++) {
575 cf_add(tmp
, wh
, yy
*w
+xx
,
576 -cf_slookup(tmp
, wh
, yy
*w
+xx
) +
577 extend_options(w
, h
, n
, map
, xx
, yy
, -1));
582 * Finally, go through and normalise the region labels into
583 * order, meaning that indistinguishable maps are actually
586 for (i
= 0; i
< n
; i
++)
589 for (i
= 0; i
< wh
; i
++) {
593 map
[i
] = tmp
[map
[i
]];
599 /* ----------------------------------------------------------------------
600 * Functions to handle graphs.
604 * Having got a map in a square grid, convert it into a graph
607 static int gengraph(int w
, int h
, int n
, int *map
, int *graph
)
612 * Start by setting the graph up as an adjacency matrix. We'll
613 * turn it into a list later.
615 for (i
= 0; i
< n
*n
; i
++)
619 * Iterate over the map looking for all adjacencies.
621 for (y
= 0; y
< h
; y
++)
622 for (x
= 0; x
< w
; x
++) {
625 if (x
+1 < w
&& (vx
= map
[y
*w
+(x
+1)]) != v
)
626 graph
[v
*n
+vx
] = graph
[vx
*n
+v
] = 1;
627 if (y
+1 < h
&& (vy
= map
[(y
+1)*w
+x
]) != v
)
628 graph
[v
*n
+vy
] = graph
[vy
*n
+v
] = 1;
632 * Turn the matrix into a list.
634 for (i
= j
= 0; i
< n
*n
; i
++)
641 static int graph_edge_index(int *graph
, int n
, int ngraph
, int i
, int j
)
648 while (top
- bot
> 1) {
649 mid
= (top
+ bot
) / 2;
652 else if (graph
[mid
] < v
)
660 #define graph_adjacent(graph, n, ngraph, i, j) \
661 (graph_edge_index((graph), (n), (ngraph), (i), (j)) >= 0)
663 static int graph_vertex_start(int *graph
, int n
, int ngraph
, int i
)
670 while (top
- bot
> 1) {
671 mid
= (top
+ bot
) / 2;
680 /* ----------------------------------------------------------------------
681 * Generate a four-colouring of a graph.
683 * FIXME: it would be nice if we could convert this recursion into
684 * pseudo-recursion using some sort of explicit stack array, for
685 * the sake of the Palm port and its limited stack.
688 static int fourcolour_recurse(int *graph
, int n
, int ngraph
,
689 int *colouring
, int *scratch
, random_state
*rs
)
691 int nfree
, nvert
, start
, i
, j
, k
, c
, ci
;
695 * Find the smallest number of free colours in any uncoloured
696 * vertex, and count the number of such vertices.
699 nfree
= FIVE
; /* start off bigger than FOUR! */
701 for (i
= 0; i
< n
; i
++)
702 if (colouring
[i
] < 0 && scratch
[i
*FIVE
+FOUR
] <= nfree
) {
703 if (nfree
> scratch
[i
*FIVE
+FOUR
]) {
704 nfree
= scratch
[i
*FIVE
+FOUR
];
711 * If there aren't any uncoloured vertices at all, we're done.
714 return TRUE
; /* we've got a colouring! */
717 * Pick a random vertex in that set.
719 j
= random_upto(rs
, nvert
);
720 for (i
= 0; i
< n
; i
++)
721 if (colouring
[i
] < 0 && scratch
[i
*FIVE
+FOUR
] == nfree
)
725 start
= graph_vertex_start(graph
, n
, ngraph
, i
);
728 * Loop over the possible colours for i, and recurse for each
732 for (c
= 0; c
< FOUR
; c
++)
733 if (scratch
[i
*FIVE
+c
] == 0)
735 shuffle(cs
, ci
, sizeof(*cs
), rs
);
741 * Fill in this colour.
746 * Update the scratch space to reflect a new neighbour
747 * of this colour for each neighbour of vertex i.
749 for (j
= start
; j
< ngraph
&& graph
[j
] < n
*(i
+1); j
++) {
751 if (scratch
[k
*FIVE
+c
] == 0)
752 scratch
[k
*FIVE
+FOUR
]--;
759 if (fourcolour_recurse(graph
, n
, ngraph
, colouring
, scratch
, rs
))
760 return TRUE
; /* got one! */
763 * If that didn't work, clean up and try again with a
766 for (j
= start
; j
< ngraph
&& graph
[j
] < n
*(i
+1); j
++) {
769 if (scratch
[k
*FIVE
+c
] == 0)
770 scratch
[k
*FIVE
+FOUR
]++;
776 * If we reach here, we were unable to find a colouring at all.
777 * (This doesn't necessarily mean the Four Colour Theorem is
778 * violated; it might just mean we've gone down a dead end and
779 * need to back up and look somewhere else. It's only an FCT
780 * violation if we get all the way back up to the top level and
786 static void fourcolour(int *graph
, int n
, int ngraph
, int *colouring
,
793 * For each vertex and each colour, we store the number of
794 * neighbours that have that colour. Also, we store the number
795 * of free colours for the vertex.
797 scratch
= snewn(n
* FIVE
, int);
798 for (i
= 0; i
< n
* FIVE
; i
++)
799 scratch
[i
] = (i
% FIVE
== FOUR ? FOUR
: 0);
802 * Clear the colouring to start with.
804 for (i
= 0; i
< n
; i
++)
807 i
= fourcolour_recurse(graph
, n
, ngraph
, colouring
, scratch
, rs
);
808 assert(i
); /* by the Four Colour Theorem :-) */
813 /* ----------------------------------------------------------------------
814 * Non-recursive solver.
817 struct solver_scratch
{
818 unsigned char *possible
; /* bitmap of colours for each region */
826 #ifdef SOLVER_DIAGNOSTICS
833 static struct solver_scratch
*new_scratch(int *graph
, int n
, int ngraph
)
835 struct solver_scratch
*sc
;
837 sc
= snew(struct solver_scratch
);
841 sc
->possible
= snewn(n
, unsigned char);
843 sc
->bfsqueue
= snewn(n
, int);
844 sc
->bfscolour
= snewn(n
, int);
845 #ifdef SOLVER_DIAGNOSTICS
846 sc
->bfsprev
= snewn(n
, int);
852 static void free_scratch(struct solver_scratch
*sc
)
856 sfree(sc
->bfscolour
);
857 #ifdef SOLVER_DIAGNOSTICS
864 * Count the bits in a word. Only needs to cope with FOUR bits.
866 static int bitcount(int word
)
868 assert(FOUR
<= 4); /* or this needs changing */
869 word
= ((word
& 0xA) >> 1) + (word
& 0x5);
870 word
= ((word
& 0xC) >> 2) + (word
& 0x3);
874 #ifdef SOLVER_DIAGNOSTICS
875 static const char colnames
[FOUR
] = { 'R', 'Y', 'G', 'B' };
878 static int place_colour(struct solver_scratch
*sc
,
879 int *colouring
, int index
, int colour
880 #ifdef SOLVER_DIAGNOSTICS
885 int *graph
= sc
->graph
, n
= sc
->n
, ngraph
= sc
->ngraph
;
888 if (!(sc
->possible
[index
] & (1 << colour
))) {
889 #ifdef SOLVER_DIAGNOSTICS
891 printf("%*scannot place %c in region %d\n", 2*sc
->depth
, "",
892 colnames
[colour
], index
);
894 return FALSE
; /* can't do it */
897 sc
->possible
[index
] = 1 << colour
;
898 colouring
[index
] = colour
;
900 #ifdef SOLVER_DIAGNOSTICS
902 printf("%*s%s %c in region %d\n", 2*sc
->depth
, "",
903 verb
, colnames
[colour
], index
);
907 * Rule out this colour from all the region's neighbours.
909 for (j
= graph_vertex_start(graph
, n
, ngraph
, index
);
910 j
< ngraph
&& graph
[j
] < n
*(index
+1); j
++) {
911 k
= graph
[j
] - index
*n
;
912 #ifdef SOLVER_DIAGNOSTICS
913 if (verbose
&& (sc
->possible
[k
] & (1 << colour
)))
914 printf("%*s ruling out %c in region %d\n", 2*sc
->depth
, "",
915 colnames
[colour
], k
);
917 sc
->possible
[k
] &= ~(1 << colour
);
923 #ifdef SOLVER_DIAGNOSTICS
924 static char *colourset(char *buf
, int set
)
930 for (i
= 0; i
< FOUR
; i
++)
931 if (set
& (1 << i
)) {
932 p
+= sprintf(p
, "%s%c", sep
, colnames
[i
]);
941 * Returns 0 for impossible, 1 for success, 2 for failure to
942 * converge (i.e. puzzle is either ambiguous or just too
945 static int map_solver(struct solver_scratch
*sc
,
946 int *graph
, int n
, int ngraph
, int *colouring
,
951 if (sc
->depth
== 0) {
953 * Initialise scratch space.
955 for (i
= 0; i
< n
; i
++)
956 sc
->possible
[i
] = (1 << FOUR
) - 1;
961 for (i
= 0; i
< n
; i
++)
962 if (colouring
[i
] >= 0) {
963 if (!place_colour(sc
, colouring
, i
, colouring
[i
]
964 #ifdef SOLVER_DIAGNOSTICS
968 #ifdef SOLVER_DIAGNOSTICS
970 printf("%*sinitial clue set is inconsistent\n",
973 return 0; /* the clues aren't even consistent! */
979 * Now repeatedly loop until we find nothing further to do.
982 int done_something
= FALSE
;
984 if (difficulty
< DIFF_EASY
)
985 break; /* can't do anything at all! */
988 * Simplest possible deduction: find a region with only one
991 for (i
= 0; i
< n
; i
++) if (colouring
[i
] < 0) {
992 int p
= sc
->possible
[i
];
995 #ifdef SOLVER_DIAGNOSTICS
997 printf("%*sregion %d has no possible colours left\n",
1000 return 0; /* puzzle is inconsistent */
1003 if ((p
& (p
-1)) == 0) { /* p is a power of two */
1005 for (c
= 0; c
< FOUR
; c
++)
1009 ret
= place_colour(sc
, colouring
, i
, c
1010 #ifdef SOLVER_DIAGNOSTICS
1015 * place_colour() can only fail if colour c was not
1016 * even a _possibility_ for region i, and we're
1017 * pretty sure it was because we checked before
1018 * calling place_colour(). So we can safely assert
1019 * here rather than having to return a nice
1020 * friendly error code.
1023 done_something
= TRUE
;
1030 if (difficulty
< DIFF_NORMAL
)
1031 break; /* can't do anything harder */
1034 * Failing that, go up one level. Look for pairs of regions
1035 * which (a) both have the same pair of possible colours,
1036 * (b) are adjacent to one another, (c) are adjacent to the
1037 * same region, and (d) that region still thinks it has one
1038 * or both of those possible colours.
1040 * Simplest way to do this is by going through the graph
1041 * edge by edge, so that we start with property (b) and
1042 * then look for (a) and finally (c) and (d).
1044 for (i
= 0; i
< ngraph
; i
++) {
1045 int j1
= graph
[i
] / n
, j2
= graph
[i
] % n
;
1047 #ifdef SOLVER_DIAGNOSTICS
1048 int started
= FALSE
;
1052 continue; /* done it already, other way round */
1054 if (colouring
[j1
] >= 0 || colouring
[j2
] >= 0)
1055 continue; /* they're not undecided */
1057 if (sc
->possible
[j1
] != sc
->possible
[j2
])
1058 continue; /* they don't have the same possibles */
1060 v
= sc
->possible
[j1
];
1062 * See if v contains exactly two set bits.
1064 v2
= v
& -v
; /* find lowest set bit */
1065 v2
= v
& ~v2
; /* clear it */
1066 if (v2
== 0 || (v2
& (v2
-1)) != 0) /* not power of 2 */
1070 * We've found regions j1 and j2 satisfying properties
1071 * (a) and (b): they have two possible colours between
1072 * them, and since they're adjacent to one another they
1073 * must use _both_ those colours between them.
1074 * Therefore, if they are both adjacent to any other
1075 * region then that region cannot be either colour.
1077 * Go through the neighbours of j1 and see if any are
1080 for (j
= graph_vertex_start(graph
, n
, ngraph
, j1
);
1081 j
< ngraph
&& graph
[j
] < n
*(j1
+1); j
++) {
1082 k
= graph
[j
] - j1
*n
;
1083 if (graph_adjacent(graph
, n
, ngraph
, k
, j2
) &&
1084 (sc
->possible
[k
] & v
)) {
1085 #ifdef SOLVER_DIAGNOSTICS
1089 printf("%*sadjacent regions %d,%d share colours"
1090 " %s\n", 2*sc
->depth
, "", j1
, j2
,
1093 printf("%*s ruling out %s in region %d\n",2*sc
->depth
,
1094 "", colourset(buf
, sc
->possible
[k
] & v
), k
);
1097 sc
->possible
[k
] &= ~v
;
1098 done_something
= TRUE
;
1106 if (difficulty
< DIFF_HARD
)
1107 break; /* can't do anything harder */
1110 * Right; now we get creative. Now we're going to look for
1111 * `forcing chains'. A forcing chain is a path through the
1112 * graph with the following properties:
1114 * (a) Each vertex on the path has precisely two possible
1117 * (b) Each pair of vertices which are adjacent on the
1118 * path share at least one possible colour in common.
1120 * (c) Each vertex in the middle of the path shares _both_
1121 * of its colours with at least one of its neighbours
1122 * (not the same one with both neighbours).
1124 * These together imply that at least one of the possible
1125 * colour choices at one end of the path forces _all_ the
1126 * rest of the colours along the path. In order to make
1127 * real use of this, we need further properties:
1129 * (c) Ruling out some colour C from the vertex at one end
1130 * of the path forces the vertex at the other end to
1133 * (d) The two end vertices are mutually adjacent to some
1136 * (e) That third vertex currently has C as a possibility.
1138 * If we can find all of that lot, we can deduce that at
1139 * least one of the two ends of the forcing chain has
1140 * colour C, and that therefore the mutually adjacent third
1143 * To find forcing chains, we're going to start a bfs at
1144 * each suitable vertex of the graph, once for each of its
1145 * two possible colours.
1147 for (i
= 0; i
< n
; i
++) {
1150 if (colouring
[i
] >= 0 || bitcount(sc
->possible
[i
]) != 2)
1153 for (c
= 0; c
< FOUR
; c
++)
1154 if (sc
->possible
[i
] & (1 << c
)) {
1155 int j
, k
, gi
, origc
, currc
, head
, tail
;
1157 * Try a bfs from this vertex, ruling out
1160 * Within this loop, we work in colour bitmaps
1161 * rather than actual colours, because
1162 * converting back and forth is a needless
1163 * computational expense.
1168 for (j
= 0; j
< n
; j
++) {
1169 sc
->bfscolour
[j
] = -1;
1170 #ifdef SOLVER_DIAGNOSTICS
1171 sc
->bfsprev
[j
] = -1;
1175 sc
->bfsqueue
[tail
++] = i
;
1176 sc
->bfscolour
[i
] = sc
->possible
[i
] &~ origc
;
1178 while (head
< tail
) {
1179 j
= sc
->bfsqueue
[head
++];
1180 currc
= sc
->bfscolour
[j
];
1183 * Try neighbours of j.
1185 for (gi
= graph_vertex_start(graph
, n
, ngraph
, j
);
1186 gi
< ngraph
&& graph
[gi
] < n
*(j
+1); gi
++) {
1187 k
= graph
[gi
] - j
*n
;
1190 * To continue with the bfs in vertex
1191 * k, we need k to be
1192 * (a) not already visited
1193 * (b) have two possible colours
1194 * (c) those colours include currc.
1197 if (sc
->bfscolour
[k
] < 0 &&
1199 bitcount(sc
->possible
[k
]) == 2 &&
1200 (sc
->possible
[k
] & currc
)) {
1201 sc
->bfsqueue
[tail
++] = k
;
1203 sc
->possible
[k
] &~ currc
;
1204 #ifdef SOLVER_DIAGNOSTICS
1210 * One other possibility is that k
1211 * might be the region in which we can
1212 * make a real deduction: if it's
1213 * adjacent to i, contains currc as a
1214 * possibility, and currc is equal to
1215 * the original colour we ruled out.
1217 if (currc
== origc
&&
1218 graph_adjacent(graph
, n
, ngraph
, k
, i
) &&
1219 (sc
->possible
[k
] & currc
)) {
1220 #ifdef SOLVER_DIAGNOSTICS
1222 char buf
[80], *sep
= "";
1225 printf("%*sforcing chain, colour %s, ",
1227 colourset(buf
, origc
));
1228 for (r
= j
; r
!= -1; r
= sc
->bfsprev
[r
]) {
1229 printf("%s%d", sep
, r
);
1232 printf("\n%*s ruling out %s in region"
1233 " %d\n", 2*sc
->depth
, "",
1234 colourset(buf
, origc
), k
);
1237 sc
->possible
[k
] &= ~origc
;
1238 done_something
= TRUE
;
1247 if (!done_something
)
1252 * See if we've got a complete solution, and return if so.
1254 for (i
= 0; i
< n
; i
++)
1255 if (colouring
[i
] < 0)
1258 #ifdef SOLVER_DIAGNOSTICS
1260 printf("%*sone solution found\n", 2*sc
->depth
, "");
1262 return 1; /* success! */
1266 * If recursion is not permissible, we now give up.
1268 if (difficulty
< DIFF_RECURSE
) {
1269 #ifdef SOLVER_DIAGNOSTICS
1271 printf("%*sunable to proceed further without recursion\n",
1274 return 2; /* unable to complete */
1278 * Now we've got to do something recursive. So first hunt for a
1279 * currently-most-constrained region.
1283 struct solver_scratch
*rsc
;
1284 int *subcolouring
, *origcolouring
;
1286 int we_already_got_one
;
1291 for (i
= 0; i
< n
; i
++) if (colouring
[i
] < 0) {
1292 int p
= sc
->possible
[i
];
1293 enum { compile_time_assertion
= 1 / (FOUR
<= 4) };
1296 /* Count the set bits. */
1297 c
= (p
& 5) + ((p
>> 1) & 5);
1298 c
= (c
& 3) + ((c
>> 2) & 3);
1299 assert(c
> 1); /* or colouring[i] would be >= 0 */
1307 assert(best
>= 0); /* or we'd be solved already */
1309 #ifdef SOLVER_DIAGNOSTICS
1311 printf("%*srecursing on region %d\n", 2*sc
->depth
, "", best
);
1315 * Now iterate over the possible colours for this region.
1317 rsc
= new_scratch(graph
, n
, ngraph
);
1318 rsc
->depth
= sc
->depth
+ 1;
1319 origcolouring
= snewn(n
, int);
1320 memcpy(origcolouring
, colouring
, n
* sizeof(int));
1321 subcolouring
= snewn(n
, int);
1322 we_already_got_one
= FALSE
;
1325 for (i
= 0; i
< FOUR
; i
++) {
1326 if (!(sc
->possible
[best
] & (1 << i
)))
1329 memcpy(rsc
->possible
, sc
->possible
, n
);
1330 memcpy(subcolouring
, origcolouring
, n
* sizeof(int));
1332 place_colour(rsc
, subcolouring
, best
, i
1333 #ifdef SOLVER_DIAGNOSTICS
1338 subret
= map_solver(rsc
, graph
, n
, ngraph
,
1339 subcolouring
, difficulty
);
1341 #ifdef SOLVER_DIAGNOSTICS
1343 printf("%*sretracting %c in region %d; found %s\n",
1344 2*sc
->depth
, "", colnames
[i
], best
,
1345 subret
== 0 ?
"no solutions" :
1346 subret
== 1 ?
"one solution" : "multiple solutions");
1351 * If this possibility turned up more than one valid
1352 * solution, or if it turned up one and we already had
1353 * one, we're definitely ambiguous.
1355 if (subret
== 2 || (subret
== 1 && we_already_got_one
)) {
1361 * If this possibility turned up one valid solution and
1362 * it's the first we've seen, copy it into the output.
1365 memcpy(colouring
, subcolouring
, n
* sizeof(int));
1366 we_already_got_one
= TRUE
;
1371 * Otherwise, this guess led to a contradiction, so we
1376 sfree(subcolouring
);
1379 #ifdef SOLVER_DIAGNOSTICS
1380 if (verbose
&& sc
->depth
== 0) {
1381 printf("%*s%s found\n",
1383 ret
== 0 ?
"no solutions" :
1384 ret
== 1 ?
"one solution" : "multiple solutions");
1391 /* ----------------------------------------------------------------------
1392 * Game generation main function.
1395 static char *new_game_desc(game_params
*params
, random_state
*rs
,
1396 char **aux
, int interactive
)
1398 struct solver_scratch
*sc
= NULL
;
1399 int *map
, *graph
, ngraph
, *colouring
, *colouring2
, *regions
;
1400 int i
, j
, w
, h
, n
, solveret
, cfreq
[FOUR
];
1403 #ifdef GENERATION_DIAGNOSTICS
1407 int retlen
, retsize
;
1416 map
= snewn(wh
, int);
1417 graph
= snewn(n
*n
, int);
1418 colouring
= snewn(n
, int);
1419 colouring2
= snewn(n
, int);
1420 regions
= snewn(n
, int);
1423 * This is the minimum difficulty below which we'll completely
1424 * reject a map design. Normally we set this to one below the
1425 * requested difficulty, ensuring that we have the right
1426 * result. However, for particularly dense maps or maps with
1427 * particularly few regions it might not be possible to get the
1428 * desired difficulty, so we will eventually drop this down to
1429 * -1 to indicate that any old map will do.
1431 mindiff
= params
->diff
;
1439 genmap(w
, h
, n
, map
, rs
);
1441 #ifdef GENERATION_DIAGNOSTICS
1442 for (y
= 0; y
< h
; y
++) {
1443 for (x
= 0; x
< w
; x
++) {
1448 putchar('a' + v
-36);
1450 putchar('A' + v
-10);
1459 * Convert the map into a graph.
1461 ngraph
= gengraph(w
, h
, n
, map
, graph
);
1463 #ifdef GENERATION_DIAGNOSTICS
1464 for (i
= 0; i
< ngraph
; i
++)
1465 printf("%d-%d\n", graph
[i
]/n
, graph
[i
]%n
);
1471 fourcolour(graph
, n
, ngraph
, colouring
, rs
);
1473 #ifdef GENERATION_DIAGNOSTICS
1474 for (i
= 0; i
< n
; i
++)
1475 printf("%d: %d\n", i
, colouring
[i
]);
1477 for (y
= 0; y
< h
; y
++) {
1478 for (x
= 0; x
< w
; x
++) {
1479 int v
= colouring
[map
[y
*w
+x
]];
1481 putchar('a' + v
-36);
1483 putchar('A' + v
-10);
1492 * Encode the solution as an aux string.
1494 if (*aux
) /* in case we've come round again */
1496 retlen
= retsize
= 0;
1498 for (i
= 0; i
< n
; i
++) {
1501 if (colouring
[i
] < 0)
1504 len
= sprintf(buf
, "%s%d:%d", i ?
";" : "S;", colouring
[i
], i
);
1505 if (retlen
+ len
>= retsize
) {
1506 retsize
= retlen
+ len
+ 256;
1507 ret
= sresize(ret
, retsize
, char);
1509 strcpy(ret
+ retlen
, buf
);
1515 * Remove the region colours one by one, keeping
1516 * solubility. Also ensure that there always remains at
1517 * least one region of every colour, so that the user can
1518 * drag from somewhere.
1520 for (i
= 0; i
< FOUR
; i
++)
1522 for (i
= 0; i
< n
; i
++) {
1524 cfreq
[colouring
[i
]]++;
1526 for (i
= 0; i
< FOUR
; i
++)
1530 shuffle(regions
, n
, sizeof(*regions
), rs
);
1532 if (sc
) free_scratch(sc
);
1533 sc
= new_scratch(graph
, n
, ngraph
);
1535 for (i
= 0; i
< n
; i
++) {
1538 if (cfreq
[colouring
[j
]] == 1)
1539 continue; /* can't remove last region of colour */
1541 memcpy(colouring2
, colouring
, n
*sizeof(int));
1543 solveret
= map_solver(sc
, graph
, n
, ngraph
, colouring2
,
1545 assert(solveret
>= 0); /* mustn't be impossible! */
1546 if (solveret
== 1) {
1547 cfreq
[colouring
[j
]]--;
1552 #ifdef GENERATION_DIAGNOSTICS
1553 for (i
= 0; i
< n
; i
++)
1554 if (colouring
[i
] >= 0) {
1558 putchar('a' + i
-36);
1560 putchar('A' + i
-10);
1563 printf(": %d\n", colouring
[i
]);
1568 * Finally, check that the puzzle is _at least_ as hard as
1569 * required, and indeed that it isn't already solved.
1570 * (Calling map_solver with negative difficulty ensures the
1571 * latter - if a solver which _does nothing_ can solve it,
1574 memcpy(colouring2
, colouring
, n
*sizeof(int));
1575 if (map_solver(sc
, graph
, n
, ngraph
, colouring2
,
1576 mindiff
- 1) == 1) {
1578 * Drop minimum difficulty if necessary.
1580 if (mindiff
> 0 && (n
< 9 || n
> 2*wh
/3)) {
1582 mindiff
= 0; /* give up and go for Easy */
1591 * Encode as a game ID. We do this by:
1593 * - first going along the horizontal edges row by row, and
1594 * then the vertical edges column by column
1595 * - encoding the lengths of runs of edges and runs of
1597 * - the decoder will reconstitute the region boundaries from
1598 * this and automatically number them the same way we did
1599 * - then we encode the initial region colours in a Slant-like
1600 * fashion (digits 0-3 interspersed with letters giving
1601 * lengths of runs of empty spaces).
1603 retlen
= retsize
= 0;
1610 * Start with a notional non-edge, so that there'll be an
1611 * explicit `a' to distinguish the case where we start with
1617 for (i
= 0; i
< w
*(h
-1) + (w
-1)*h
; i
++) {
1618 int x
, y
, dx
, dy
, v
;
1621 /* Horizontal edge. */
1627 /* Vertical edge. */
1628 x
= (i
- w
*(h
-1)) / h
;
1629 y
= (i
- w
*(h
-1)) % h
;
1634 if (retlen
+ 10 >= retsize
) {
1635 retsize
= retlen
+ 256;
1636 ret
= sresize(ret
, retsize
, char);
1639 v
= (map
[y
*w
+x
] != map
[(y
+dy
)*w
+(x
+dx
)]);
1642 ret
[retlen
++] = 'a'-1 + run
;
1647 * 'z' is a special case in this encoding. Rather
1648 * than meaning a run of 26 and a state switch, it
1649 * means a run of 25 and _no_ state switch, because
1650 * otherwise there'd be no way to encode runs of
1654 ret
[retlen
++] = 'z';
1661 ret
[retlen
++] = 'a'-1 + run
;
1662 ret
[retlen
++] = ',';
1665 for (i
= 0; i
< n
; i
++) {
1666 if (retlen
+ 10 >= retsize
) {
1667 retsize
= retlen
+ 256;
1668 ret
= sresize(ret
, retsize
, char);
1671 if (colouring
[i
] < 0) {
1673 * In _this_ encoding, 'z' is a run of 26, since
1674 * there's no implicit state switch after each run.
1675 * Confusingly different, but more compact.
1678 ret
[retlen
++] = 'z';
1684 ret
[retlen
++] = 'a'-1 + run
;
1685 ret
[retlen
++] = '0' + colouring
[i
];
1690 ret
[retlen
++] = 'a'-1 + run
;
1693 assert(retlen
< retsize
);
1706 static char *parse_edge_list(game_params
*params
, char **desc
, int *map
)
1708 int w
= params
->w
, h
= params
->h
, wh
= w
*h
, n
= params
->n
;
1709 int i
, k
, pos
, state
;
1712 dsf_init(map
+wh
, wh
);
1718 * Parse the game description to get the list of edges, and
1719 * build up a disjoint set forest as we go (by identifying
1720 * pairs of squares whenever the edge list shows a non-edge).
1722 while (*p
&& *p
!= ',') {
1723 if (*p
< 'a' || *p
> 'z')
1724 return "Unexpected character in edge list";
1735 } else if (pos
< w
*(h
-1)) {
1736 /* Horizontal edge. */
1741 } else if (pos
< 2*wh
-w
-h
) {
1742 /* Vertical edge. */
1743 x
= (pos
- w
*(h
-1)) / h
;
1744 y
= (pos
- w
*(h
-1)) % h
;
1748 return "Too much data in edge list";
1750 dsf_merge(map
+wh
, y
*w
+x
, (y
+dy
)*w
+(x
+dx
));
1758 assert(pos
<= 2*wh
-w
-h
);
1760 return "Too little data in edge list";
1763 * Now go through again and allocate region numbers.
1766 for (i
= 0; i
< wh
; i
++)
1768 for (i
= 0; i
< wh
; i
++) {
1769 k
= dsf_canonify(map
+wh
, i
);
1775 return "Edge list defines the wrong number of regions";
1782 static char *validate_desc(game_params
*params
, char *desc
)
1784 int w
= params
->w
, h
= params
->h
, wh
= w
*h
, n
= params
->n
;
1789 map
= snewn(2*wh
, int);
1790 ret
= parse_edge_list(params
, &desc
, map
);
1796 return "Expected comma before clue list";
1797 desc
++; /* eat comma */
1801 if (*desc
>= '0' && *desc
< '0'+FOUR
)
1803 else if (*desc
>= 'a' && *desc
<= 'z')
1804 area
+= *desc
- 'a' + 1;
1806 return "Unexpected character in clue list";
1810 return "Too little data in clue list";
1812 return "Too much data in clue list";
1817 static game_state
*new_game(midend
*me
, game_params
*params
, char *desc
)
1819 int w
= params
->w
, h
= params
->h
, wh
= w
*h
, n
= params
->n
;
1822 game_state
*state
= snew(game_state
);
1825 state
->colouring
= snewn(n
, int);
1826 for (i
= 0; i
< n
; i
++)
1827 state
->colouring
[i
] = -1;
1828 state
->pencil
= snewn(n
, int);
1829 for (i
= 0; i
< n
; i
++)
1830 state
->pencil
[i
] = 0;
1832 state
->completed
= state
->cheated
= FALSE
;
1834 state
->map
= snew(struct map
);
1835 state
->map
->refcount
= 1;
1836 state
->map
->map
= snewn(wh
*4, int);
1837 state
->map
->graph
= snewn(n
*n
, int);
1839 state
->map
->immutable
= snewn(n
, int);
1840 for (i
= 0; i
< n
; i
++)
1841 state
->map
->immutable
[i
] = FALSE
;
1847 ret
= parse_edge_list(params
, &p
, state
->map
->map
);
1852 * Set up the other three quadrants in `map'.
1854 for (i
= wh
; i
< 4*wh
; i
++)
1855 state
->map
->map
[i
] = state
->map
->map
[i
% wh
];
1861 * Now process the clue list.
1865 if (*p
>= '0' && *p
< '0'+FOUR
) {
1866 state
->colouring
[pos
] = *p
- '0';
1867 state
->map
->immutable
[pos
] = TRUE
;
1870 assert(*p
>= 'a' && *p
<= 'z');
1871 pos
+= *p
- 'a' + 1;
1877 state
->map
->ngraph
= gengraph(w
, h
, n
, state
->map
->map
, state
->map
->graph
);
1880 * Attempt to smooth out some of the more jagged region
1881 * outlines by the judicious use of diagonally divided squares.
1884 random_state
*rs
= random_new(desc
, strlen(desc
));
1885 int *squares
= snewn(wh
, int);
1888 for (i
= 0; i
< wh
; i
++)
1890 shuffle(squares
, wh
, sizeof(*squares
), rs
);
1893 done_something
= FALSE
;
1894 for (i
= 0; i
< wh
; i
++) {
1895 int y
= squares
[i
] / w
, x
= squares
[i
] % w
;
1896 int c
= state
->map
->map
[y
*w
+x
];
1899 if (x
== 0 || x
== w
-1 || y
== 0 || y
== h
-1)
1902 if (state
->map
->map
[TE
* wh
+ y
*w
+x
] !=
1903 state
->map
->map
[BE
* wh
+ y
*w
+x
])
1906 tc
= state
->map
->map
[BE
* wh
+ (y
-1)*w
+x
];
1907 bc
= state
->map
->map
[TE
* wh
+ (y
+1)*w
+x
];
1908 lc
= state
->map
->map
[RE
* wh
+ y
*w
+(x
-1)];
1909 rc
= state
->map
->map
[LE
* wh
+ y
*w
+(x
+1)];
1912 * If this square is adjacent on two sides to one
1913 * region and on the other two sides to the other
1914 * region, and is itself one of the two regions, we can
1915 * adjust it so that it's a diagonal.
1917 if (tc
!= bc
&& (tc
== c
|| bc
== c
)) {
1918 if ((lc
== tc
&& rc
== bc
) ||
1919 (lc
== bc
&& rc
== tc
)) {
1920 state
->map
->map
[TE
* wh
+ y
*w
+x
] = tc
;
1921 state
->map
->map
[BE
* wh
+ y
*w
+x
] = bc
;
1922 state
->map
->map
[LE
* wh
+ y
*w
+x
] = lc
;
1923 state
->map
->map
[RE
* wh
+ y
*w
+x
] = rc
;
1924 done_something
= TRUE
;
1928 } while (done_something
);
1934 * Analyse the map to find a canonical line segment
1935 * corresponding to each edge, and a canonical point
1936 * corresponding to each region. The former are where we'll
1937 * eventually put error markers; the latter are where we'll put
1938 * per-region flags such as numbers (when in diagnostic mode).
1941 int *bestx
, *besty
, *an
, pass
;
1942 float *ax
, *ay
, *best
;
1944 ax
= snewn(state
->map
->ngraph
+ n
, float);
1945 ay
= snewn(state
->map
->ngraph
+ n
, float);
1946 an
= snewn(state
->map
->ngraph
+ n
, int);
1947 bestx
= snewn(state
->map
->ngraph
+ n
, int);
1948 besty
= snewn(state
->map
->ngraph
+ n
, int);
1949 best
= snewn(state
->map
->ngraph
+ n
, float);
1951 for (i
= 0; i
< state
->map
->ngraph
+ n
; i
++) {
1952 bestx
[i
] = besty
[i
] = -1;
1953 best
[i
] = 2*(w
+h
)+1;
1954 ax
[i
] = ay
[i
] = 0.0F
;
1959 * We make two passes over the map, finding all the line
1960 * segments separating regions and all the suitable points
1961 * within regions. In the first pass, we compute the
1962 * _average_ x and y coordinate of all the points in a
1963 * given class; in the second pass, for each such average
1964 * point, we find the candidate closest to it and call that
1967 * Line segments are considered to have coordinates in
1968 * their centre. Thus, at least one coordinate for any line
1969 * segment is always something-and-a-half; so we store our
1970 * coordinates as twice their normal value.
1972 for (pass
= 0; pass
< 2; pass
++) {
1975 for (y
= 0; y
< h
; y
++)
1976 for (x
= 0; x
< w
; x
++) {
1977 int ex
[4], ey
[4], ea
[4], eb
[4], en
= 0;
1980 * Look for an edge to the right of this
1981 * square, an edge below it, and an edge in the
1982 * middle of it. Also look to see if the point
1983 * at the bottom right of this square is on an
1984 * edge (and isn't a place where more than two
1989 ea
[en
] = state
->map
->map
[RE
* wh
+ y
*w
+x
];
1990 eb
[en
] = state
->map
->map
[LE
* wh
+ y
*w
+(x
+1)];
1997 ea
[en
] = state
->map
->map
[BE
* wh
+ y
*w
+x
];
1998 eb
[en
] = state
->map
->map
[TE
* wh
+ (y
+1)*w
+x
];
2004 ea
[en
] = state
->map
->map
[TE
* wh
+ y
*w
+x
];
2005 eb
[en
] = state
->map
->map
[BE
* wh
+ y
*w
+x
];
2010 if (x
+1 < w
&& y
+1 < h
) {
2011 /* bottom right corner */
2012 int oct
[8], othercol
, nchanges
;
2013 oct
[0] = state
->map
->map
[RE
* wh
+ y
*w
+x
];
2014 oct
[1] = state
->map
->map
[LE
* wh
+ y
*w
+(x
+1)];
2015 oct
[2] = state
->map
->map
[BE
* wh
+ y
*w
+(x
+1)];
2016 oct
[3] = state
->map
->map
[TE
* wh
+ (y
+1)*w
+(x
+1)];
2017 oct
[4] = state
->map
->map
[LE
* wh
+ (y
+1)*w
+(x
+1)];
2018 oct
[5] = state
->map
->map
[RE
* wh
+ (y
+1)*w
+x
];
2019 oct
[6] = state
->map
->map
[TE
* wh
+ (y
+1)*w
+x
];
2020 oct
[7] = state
->map
->map
[BE
* wh
+ y
*w
+x
];
2024 for (i
= 0; i
< 8; i
++) {
2025 if (oct
[i
] != oct
[0]) {
2028 else if (othercol
!= oct
[i
])
2029 break; /* three colours at this point */
2031 if (oct
[i
] != oct
[(i
+1) & 7])
2036 * Now if there are exactly two regions at
2037 * this point (not one, and not three or
2038 * more), and only two changes around the
2039 * loop, then this is a valid place to put
2042 if (i
== 8 && othercol
>= 0 && nchanges
== 2) {
2051 * If there's exactly _one_ region at this
2052 * point, on the other hand, it's a valid
2053 * place to put a region centre.
2056 ea
[en
] = eb
[en
] = oct
[0];
2064 * Now process the points we've found, one by
2067 for (i
= 0; i
< en
; i
++) {
2068 int emin
= min(ea
[i
], eb
[i
]);
2069 int emax
= max(ea
[i
], eb
[i
]);
2075 graph_edge_index(state
->map
->graph
, n
,
2076 state
->map
->ngraph
, emin
,
2080 gindex
= state
->map
->ngraph
+ emin
;
2083 assert(gindex
>= 0);
2087 * In pass 0, accumulate the values
2088 * we'll use to compute the average
2091 ax
[gindex
] += ex
[i
];
2092 ay
[gindex
] += ey
[i
];
2096 * In pass 1, work out whether this
2097 * point is closer to the average than
2098 * the last one we've seen.
2102 assert(an
[gindex
] > 0);
2103 dx
= ex
[i
] - ax
[gindex
];
2104 dy
= ey
[i
] - ay
[gindex
];
2105 d
= sqrt(dx
*dx
+ dy
*dy
);
2106 if (d
< best
[gindex
]) {
2108 bestx
[gindex
] = ex
[i
];
2109 besty
[gindex
] = ey
[i
];
2116 for (i
= 0; i
< state
->map
->ngraph
+ n
; i
++)
2124 state
->map
->edgex
= snewn(state
->map
->ngraph
, int);
2125 state
->map
->edgey
= snewn(state
->map
->ngraph
, int);
2126 memcpy(state
->map
->edgex
, bestx
, state
->map
->ngraph
* sizeof(int));
2127 memcpy(state
->map
->edgey
, besty
, state
->map
->ngraph
* sizeof(int));
2129 state
->map
->regionx
= snewn(n
, int);
2130 state
->map
->regiony
= snewn(n
, int);
2131 memcpy(state
->map
->regionx
, bestx
+ state
->map
->ngraph
, n
*sizeof(int));
2132 memcpy(state
->map
->regiony
, besty
+ state
->map
->ngraph
, n
*sizeof(int));
2134 for (i
= 0; i
< state
->map
->ngraph
; i
++)
2135 if (state
->map
->edgex
[i
] < 0) {
2136 /* Find the other representation of this edge. */
2137 int e
= state
->map
->graph
[i
];
2138 int iprime
= graph_edge_index(state
->map
->graph
, n
,
2139 state
->map
->ngraph
, e
%n
, e
/n
);
2140 assert(state
->map
->edgex
[iprime
] >= 0);
2141 state
->map
->edgex
[i
] = state
->map
->edgex
[iprime
];
2142 state
->map
->edgey
[i
] = state
->map
->edgey
[iprime
];
2156 static game_state
*dup_game(game_state
*state
)
2158 game_state
*ret
= snew(game_state
);
2161 ret
->colouring
= snewn(state
->p
.n
, int);
2162 memcpy(ret
->colouring
, state
->colouring
, state
->p
.n
* sizeof(int));
2163 ret
->pencil
= snewn(state
->p
.n
, int);
2164 memcpy(ret
->pencil
, state
->pencil
, state
->p
.n
* sizeof(int));
2165 ret
->map
= state
->map
;
2166 ret
->map
->refcount
++;
2167 ret
->completed
= state
->completed
;
2168 ret
->cheated
= state
->cheated
;
2173 static void free_game(game_state
*state
)
2175 if (--state
->map
->refcount
<= 0) {
2176 sfree(state
->map
->map
);
2177 sfree(state
->map
->graph
);
2178 sfree(state
->map
->immutable
);
2179 sfree(state
->map
->edgex
);
2180 sfree(state
->map
->edgey
);
2181 sfree(state
->map
->regionx
);
2182 sfree(state
->map
->regiony
);
2185 sfree(state
->pencil
);
2186 sfree(state
->colouring
);
2190 static char *solve_game(game_state
*state
, game_state
*currstate
,
2191 char *aux
, char **error
)
2198 struct solver_scratch
*sc
;
2202 int retlen
, retsize
;
2204 colouring
= snewn(state
->map
->n
, int);
2205 memcpy(colouring
, state
->colouring
, state
->map
->n
* sizeof(int));
2207 sc
= new_scratch(state
->map
->graph
, state
->map
->n
, state
->map
->ngraph
);
2208 sret
= map_solver(sc
, state
->map
->graph
, state
->map
->n
,
2209 state
->map
->ngraph
, colouring
, DIFFCOUNT
-1);
2215 *error
= "Puzzle is inconsistent";
2217 *error
= "Unable to find a unique solution for this puzzle";
2222 ret
= snewn(retsize
, char);
2226 for (i
= 0; i
< state
->map
->n
; i
++) {
2229 assert(colouring
[i
] >= 0);
2230 if (colouring
[i
] == currstate
->colouring
[i
])
2232 assert(!state
->map
->immutable
[i
]);
2234 len
= sprintf(buf
, ";%d:%d", colouring
[i
], i
);
2235 if (retlen
+ len
>= retsize
) {
2236 retsize
= retlen
+ len
+ 256;
2237 ret
= sresize(ret
, retsize
, char);
2239 strcpy(ret
+ retlen
, buf
);
2250 static int game_can_format_as_text_now(game_params
*params
)
2255 static char *game_text_format(game_state
*state
)
2264 * - -2 means no drag currently active.
2265 * - >=0 means we're dragging a solid colour.
2266 * - -1 means we're dragging a blank space, and drag_pencil
2267 * might or might not add some pencil-mark stipples to that.
2275 static game_ui
*new_ui(game_state
*state
)
2277 game_ui
*ui
= snew(game_ui
);
2278 ui
->dragx
= ui
->dragy
= -1;
2279 ui
->drag_colour
= -2;
2280 ui
->show_numbers
= FALSE
;
2284 static void free_ui(game_ui
*ui
)
2289 static char *encode_ui(game_ui
*ui
)
2294 static void decode_ui(game_ui
*ui
, char *encoding
)
2298 static void game_changed_state(game_ui
*ui
, game_state
*oldstate
,
2299 game_state
*newstate
)
2303 struct game_drawstate
{
2305 unsigned long *drawn
, *todraw
;
2307 int dragx
, dragy
, drag_visible
;
2311 /* Flags in `drawn'. */
2312 #define ERR_BASE 0x00800000L
2313 #define ERR_MASK 0xFF800000L
2314 #define PENCIL_T_BASE 0x00080000L
2315 #define PENCIL_T_MASK 0x00780000L
2316 #define PENCIL_B_BASE 0x00008000L
2317 #define PENCIL_B_MASK 0x00078000L
2318 #define PENCIL_MASK 0x007F8000L
2319 #define SHOW_NUMBERS 0x00004000L
2321 #define TILESIZE (ds->tilesize)
2322 #define BORDER (TILESIZE)
2323 #define COORD(x) ( (x) * TILESIZE + BORDER )
2324 #define FROMCOORD(x) ( ((x) - BORDER + TILESIZE) / TILESIZE - 1 )
2326 static int region_from_coords(game_state
*state
, game_drawstate
*ds
,
2329 int w
= state
->p
.w
, h
= state
->p
.h
, wh
= w
*h
/*, n = state->p.n */;
2330 int tx
= FROMCOORD(x
), ty
= FROMCOORD(y
);
2331 int dx
= x
- COORD(tx
), dy
= y
- COORD(ty
);
2334 if (tx
< 0 || tx
>= w
|| ty
< 0 || ty
>= h
)
2335 return -1; /* border */
2337 quadrant
= 2 * (dx
> dy
) + (TILESIZE
- dx
> dy
);
2338 quadrant
= (quadrant
== 0 ? BE
:
2339 quadrant
== 1 ? LE
:
2340 quadrant
== 2 ? RE
: TE
);
2342 return state
->map
->map
[quadrant
* wh
+ ty
*w
+tx
];
2345 static char *interpret_move(game_state
*state
, game_ui
*ui
, game_drawstate
*ds
,
2346 int x
, int y
, int button
)
2348 char *bufp
, buf
[256];
2351 * Enable or disable numeric labels on regions.
2353 if (button
== 'l' || button
== 'L') {
2354 ui
->show_numbers
= !ui
->show_numbers
;
2358 if (button
== LEFT_BUTTON
|| button
== RIGHT_BUTTON
) {
2359 int r
= region_from_coords(state
, ds
, x
, y
);
2362 ui
->drag_colour
= state
->colouring
[r
];
2363 ui
->drag_pencil
= state
->pencil
[r
];
2364 if (ui
->drag_colour
>= 0)
2365 ui
->drag_pencil
= 0; /* should be already, but double-check */
2367 ui
->drag_colour
= -1;
2368 ui
->drag_pencil
= 0;
2375 if ((button
== LEFT_DRAG
|| button
== RIGHT_DRAG
) &&
2376 ui
->drag_colour
> -2) {
2382 if ((button
== LEFT_RELEASE
|| button
== RIGHT_RELEASE
) &&
2383 ui
->drag_colour
> -2) {
2384 int r
= region_from_coords(state
, ds
, x
, y
);
2385 int c
= ui
->drag_colour
;
2386 int p
= ui
->drag_pencil
;
2390 * Cancel the drag, whatever happens.
2392 ui
->drag_colour
= -2;
2393 ui
->dragx
= ui
->dragy
= -1;
2396 return ""; /* drag into border; do nothing else */
2398 if (state
->map
->immutable
[r
])
2399 return ""; /* can't change this region */
2401 if (state
->colouring
[r
] == c
&& state
->pencil
[r
] == p
)
2402 return ""; /* don't _need_ to change this region */
2404 if (button
== RIGHT_RELEASE
) {
2405 if (state
->colouring
[r
] >= 0) {
2406 /* Can't pencil on a coloured region */
2408 } else if (c
>= 0) {
2409 /* Right-dragging from colour to blank toggles one pencil */
2410 p
= state
->pencil
[r
] ^ (1 << c
);
2413 /* Otherwise, right-dragging from blank to blank is equivalent
2414 * to left-dragging. */
2418 oldp
= state
->pencil
[r
];
2419 if (c
!= state
->colouring
[r
]) {
2420 bufp
+= sprintf(bufp
, ";%c:%d", (int)(c
< 0 ?
'C' : '0' + c
), r
);
2426 for (i
= 0; i
< FOUR
; i
++)
2427 if ((oldp
^ p
) & (1 << i
))
2428 bufp
+= sprintf(bufp
, ";p%c:%d", (int)('0' + i
), r
);
2431 return dupstr(buf
+1); /* ignore first semicolon */
2437 static game_state
*execute_move(game_state
*state
, char *move
)
2440 game_state
*ret
= dup_game(state
);
2451 if ((c
== 'C' || (c
>= '0' && c
< '0'+FOUR
)) &&
2452 sscanf(move
+1, ":%d%n", &k
, &adv
) == 1 &&
2453 k
>= 0 && k
< state
->p
.n
) {
2456 if (ret
->colouring
[k
] >= 0) {
2463 ret
->pencil
[k
] ^= 1 << (c
- '0');
2465 ret
->colouring
[k
] = (c
== 'C' ?
-1 : c
- '0');
2468 } else if (*move
== 'S') {
2470 ret
->cheated
= TRUE
;
2476 if (*move
&& *move
!= ';') {
2485 * Check for completion.
2487 if (!ret
->completed
) {
2490 for (i
= 0; i
< n
; i
++)
2491 if (ret
->colouring
[i
] < 0) {
2497 for (i
= 0; i
< ret
->map
->ngraph
; i
++) {
2498 int j
= ret
->map
->graph
[i
] / n
;
2499 int k
= ret
->map
->graph
[i
] % n
;
2500 if (ret
->colouring
[j
] == ret
->colouring
[k
]) {
2508 ret
->completed
= TRUE
;
2514 /* ----------------------------------------------------------------------
2518 static void game_compute_size(game_params
*params
, int tilesize
,
2521 /* Ick: fake up `ds->tilesize' for macro expansion purposes */
2522 struct { int tilesize
; } ads
, *ds
= &ads
;
2523 ads
.tilesize
= tilesize
;
2525 *x
= params
->w
* TILESIZE
+ 2 * BORDER
+ 1;
2526 *y
= params
->h
* TILESIZE
+ 2 * BORDER
+ 1;
2529 static void game_set_size(drawing
*dr
, game_drawstate
*ds
,
2530 game_params
*params
, int tilesize
)
2532 ds
->tilesize
= tilesize
;
2534 assert(!ds
->bl
); /* set_size is never called twice */
2535 ds
->bl
= blitter_new(dr
, TILESIZE
+3, TILESIZE
+3);
2538 const float map_colours
[FOUR
][3] = {
2539 #ifdef VIVID_COLOURS
2540 /* Use more vivid colours (e.g. on the Pocket PC) */
2541 {0.75F
, 0.25F
, 0.25F
},
2544 {0.85F
, 0.85F
, 0.1F
},
2549 {0.55F
, 0.45F
, 0.35F
},
2552 const int map_hatching
[FOUR
] = {
2553 HATCH_VERT
, HATCH_SLASH
, HATCH_HORIZ
, HATCH_BACKSLASH
2556 static float *game_colours(frontend
*fe
, int *ncolours
)
2558 float *ret
= snewn(3 * NCOLOURS
, float);
2560 frontend_default_colour(fe
, &ret
[COL_BACKGROUND
* 3]);
2562 ret
[COL_GRID
* 3 + 0] = 0.0F
;
2563 ret
[COL_GRID
* 3 + 1] = 0.0F
;
2564 ret
[COL_GRID
* 3 + 2] = 0.0F
;
2566 memcpy(ret
+ COL_0
* 3, map_colours
[0], 3 * sizeof(float));
2567 memcpy(ret
+ COL_1
* 3, map_colours
[1], 3 * sizeof(float));
2568 memcpy(ret
+ COL_2
* 3, map_colours
[2], 3 * sizeof(float));
2569 memcpy(ret
+ COL_3
* 3, map_colours
[3], 3 * sizeof(float));
2571 ret
[COL_ERROR
* 3 + 0] = 1.0F
;
2572 ret
[COL_ERROR
* 3 + 1] = 0.0F
;
2573 ret
[COL_ERROR
* 3 + 2] = 0.0F
;
2575 ret
[COL_ERRTEXT
* 3 + 0] = 1.0F
;
2576 ret
[COL_ERRTEXT
* 3 + 1] = 1.0F
;
2577 ret
[COL_ERRTEXT
* 3 + 2] = 1.0F
;
2579 *ncolours
= NCOLOURS
;
2583 static game_drawstate
*game_new_drawstate(drawing
*dr
, game_state
*state
)
2585 struct game_drawstate
*ds
= snew(struct game_drawstate
);
2589 ds
->drawn
= snewn(state
->p
.w
* state
->p
.h
, unsigned long);
2590 for (i
= 0; i
< state
->p
.w
* state
->p
.h
; i
++)
2591 ds
->drawn
[i
] = 0xFFFFL
;
2592 ds
->todraw
= snewn(state
->p
.w
* state
->p
.h
, unsigned long);
2593 ds
->started
= FALSE
;
2595 ds
->drag_visible
= FALSE
;
2596 ds
->dragx
= ds
->dragy
= -1;
2601 static void game_free_drawstate(drawing
*dr
, game_drawstate
*ds
)
2606 blitter_free(dr
, ds
->bl
);
2610 static void draw_error(drawing
*dr
, game_drawstate
*ds
, int x
, int y
)
2618 coords
[0] = x
- TILESIZE
*2/5;
2621 coords
[3] = y
- TILESIZE
*2/5;
2622 coords
[4] = x
+ TILESIZE
*2/5;
2625 coords
[7] = y
+ TILESIZE
*2/5;
2626 draw_polygon(dr
, coords
, 4, COL_ERROR
, COL_GRID
);
2629 * Draw an exclamation mark in the diamond. This turns out to
2630 * look unpleasantly off-centre if done via draw_text, so I do
2631 * it by hand on the basis that exclamation marks aren't that
2632 * difficult to draw...
2635 yext
= TILESIZE
*2/5 - (xext
*2+2);
2636 draw_rect(dr
, x
-xext
, y
-yext
, xext
*2+1, yext
*2+1 - (xext
*3),
2638 draw_rect(dr
, x
-xext
, y
+yext
-xext
*2+1, xext
*2+1, xext
*2, COL_ERRTEXT
);
2641 static void draw_square(drawing
*dr
, game_drawstate
*ds
,
2642 game_params
*params
, struct map
*map
,
2643 int x
, int y
, unsigned long v
)
2645 int w
= params
->w
, h
= params
->h
, wh
= w
*h
;
2646 int tv
, bv
, xo
, yo
, i
, j
, oldj
;
2647 unsigned long errs
, pencil
, show_numbers
;
2649 errs
= v
& ERR_MASK
;
2651 pencil
= v
& PENCIL_MASK
;
2653 show_numbers
= v
& SHOW_NUMBERS
;
2658 clip(dr
, COORD(x
), COORD(y
), TILESIZE
, TILESIZE
);
2661 * Draw the region colour.
2663 draw_rect(dr
, COORD(x
), COORD(y
), TILESIZE
, TILESIZE
,
2664 (tv
== FOUR ? COL_BACKGROUND
: COL_0
+ tv
));
2666 * Draw the second region colour, if this is a diagonally
2669 if (map
->map
[TE
* wh
+ y
*w
+x
] != map
->map
[BE
* wh
+ y
*w
+x
]) {
2671 coords
[0] = COORD(x
)-1;
2672 coords
[1] = COORD(y
+1)+1;
2673 if (map
->map
[LE
* wh
+ y
*w
+x
] == map
->map
[TE
* wh
+ y
*w
+x
])
2674 coords
[2] = COORD(x
+1)+1;
2676 coords
[2] = COORD(x
)-1;
2677 coords
[3] = COORD(y
)-1;
2678 coords
[4] = COORD(x
+1)+1;
2679 coords
[5] = COORD(y
+1)+1;
2680 draw_polygon(dr
, coords
, 3,
2681 (bv
== FOUR ? COL_BACKGROUND
: COL_0
+ bv
), COL_GRID
);
2685 * Draw `pencil marks'. Currently we arrange these in a square
2686 * formation, which means we may be in trouble if the value of
2687 * FOUR changes later...
2690 for (yo
= 0; yo
< 4; yo
++)
2691 for (xo
= 0; xo
< 4; xo
++) {
2692 int te
= map
->map
[TE
* wh
+ y
*w
+x
];
2695 e
= (yo
< xo
&& yo
< 3-xo ? TE
:
2696 yo
> xo
&& yo
> 3-xo ? BE
:
2698 ee
= map
->map
[e
* wh
+ y
*w
+x
];
2700 if (xo
!= (yo
* 2 + 1) % 5)
2704 if (!(pencil
& ((ee
== te ? PENCIL_T_BASE
: PENCIL_B_BASE
) << c
)))
2708 (map
->map
[TE
* wh
+ y
*w
+x
] != map
->map
[LE
* wh
+ y
*w
+x
]))
2709 continue; /* avoid TL-BR diagonal line */
2711 (map
->map
[TE
* wh
+ y
*w
+x
] != map
->map
[RE
* wh
+ y
*w
+x
]))
2712 continue; /* avoid BL-TR diagonal line */
2714 draw_circle(dr
, COORD(x
) + (xo
+1)*TILESIZE
/5,
2715 COORD(y
) + (yo
+1)*TILESIZE
/5,
2716 TILESIZE
/7, COL_0
+ c
, COL_0
+ c
);
2720 * Draw the grid lines, if required.
2722 if (x
<= 0 || map
->map
[RE
*wh
+y
*w
+(x
-1)] != map
->map
[LE
*wh
+y
*w
+x
])
2723 draw_rect(dr
, COORD(x
), COORD(y
), 1, TILESIZE
, COL_GRID
);
2724 if (y
<= 0 || map
->map
[BE
*wh
+(y
-1)*w
+x
] != map
->map
[TE
*wh
+y
*w
+x
])
2725 draw_rect(dr
, COORD(x
), COORD(y
), TILESIZE
, 1, COL_GRID
);
2726 if (x
<= 0 || y
<= 0 ||
2727 map
->map
[RE
*wh
+(y
-1)*w
+(x
-1)] != map
->map
[TE
*wh
+y
*w
+x
] ||
2728 map
->map
[BE
*wh
+(y
-1)*w
+(x
-1)] != map
->map
[LE
*wh
+y
*w
+x
])
2729 draw_rect(dr
, COORD(x
), COORD(y
), 1, 1, COL_GRID
);
2732 * Draw error markers.
2734 for (yo
= 0; yo
< 3; yo
++)
2735 for (xo
= 0; xo
< 3; xo
++)
2736 if (errs
& (ERR_BASE
<< (yo
*3+xo
)))
2738 (COORD(x
)*2+TILESIZE
*xo
)/2,
2739 (COORD(y
)*2+TILESIZE
*yo
)/2);
2742 * Draw region numbers, if desired.
2746 for (i
= 0; i
< 2; i
++) {
2747 j
= map
->map
[(i?BE
:TE
)*wh
+y
*w
+x
];
2752 xo
= map
->regionx
[j
] - 2*x
;
2753 yo
= map
->regiony
[j
] - 2*y
;
2754 if (xo
>= 0 && xo
<= 2 && yo
>= 0 && yo
<= 2) {
2756 sprintf(buf
, "%d", j
);
2757 draw_text(dr
, (COORD(x
)*2+TILESIZE
*xo
)/2,
2758 (COORD(y
)*2+TILESIZE
*yo
)/2,
2759 FONT_VARIABLE
, 3*TILESIZE
/5,
2760 ALIGN_HCENTRE
|ALIGN_VCENTRE
,
2768 draw_update(dr
, COORD(x
), COORD(y
), TILESIZE
, TILESIZE
);
2771 static void game_redraw(drawing
*dr
, game_drawstate
*ds
, game_state
*oldstate
,
2772 game_state
*state
, int dir
, game_ui
*ui
,
2773 float animtime
, float flashtime
)
2775 int w
= state
->p
.w
, h
= state
->p
.h
, wh
= w
*h
, n
= state
->p
.n
;
2779 if (ds
->drag_visible
) {
2780 blitter_load(dr
, ds
->bl
, ds
->dragx
, ds
->dragy
);
2781 draw_update(dr
, ds
->dragx
, ds
->dragy
, TILESIZE
+ 3, TILESIZE
+ 3);
2782 ds
->drag_visible
= FALSE
;
2786 * The initial contents of the window are not guaranteed and
2787 * can vary with front ends. To be on the safe side, all games
2788 * should start by drawing a big background-colour rectangle
2789 * covering the whole window.
2794 game_compute_size(&state
->p
, TILESIZE
, &ww
, &wh
);
2795 draw_rect(dr
, 0, 0, ww
, wh
, COL_BACKGROUND
);
2796 draw_rect(dr
, COORD(0), COORD(0), w
*TILESIZE
+1, h
*TILESIZE
+1,
2799 draw_update(dr
, 0, 0, ww
, wh
);
2804 if (flash_type
== 1)
2805 flash
= (int)(flashtime
* FOUR
/ flash_length
);
2807 flash
= 1 + (int)(flashtime
* THREE
/ flash_length
);
2812 * Set up the `todraw' array.
2814 for (y
= 0; y
< h
; y
++)
2815 for (x
= 0; x
< w
; x
++) {
2816 int tv
= state
->colouring
[state
->map
->map
[TE
* wh
+ y
*w
+x
]];
2817 int bv
= state
->colouring
[state
->map
->map
[BE
* wh
+ y
*w
+x
]];
2826 if (flash_type
== 1) {
2831 } else if (flash_type
== 2) {
2836 tv
= (tv
+ flash
) % FOUR
;
2838 bv
= (bv
+ flash
) % FOUR
;
2847 for (i
= 0; i
< FOUR
; i
++) {
2848 if (state
->colouring
[state
->map
->map
[TE
* wh
+ y
*w
+x
]] < 0 &&
2849 (state
->pencil
[state
->map
->map
[TE
* wh
+ y
*w
+x
]] & (1<<i
)))
2850 v
|= PENCIL_T_BASE
<< i
;
2851 if (state
->colouring
[state
->map
->map
[BE
* wh
+ y
*w
+x
]] < 0 &&
2852 (state
->pencil
[state
->map
->map
[BE
* wh
+ y
*w
+x
]] & (1<<i
)))
2853 v
|= PENCIL_B_BASE
<< i
;
2856 if (ui
->show_numbers
)
2859 ds
->todraw
[y
*w
+x
] = v
;
2863 * Add error markers to the `todraw' array.
2865 for (i
= 0; i
< state
->map
->ngraph
; i
++) {
2866 int v1
= state
->map
->graph
[i
] / n
;
2867 int v2
= state
->map
->graph
[i
] % n
;
2870 if (state
->colouring
[v1
] < 0 || state
->colouring
[v2
] < 0)
2872 if (state
->colouring
[v1
] != state
->colouring
[v2
])
2875 x
= state
->map
->edgex
[i
];
2876 y
= state
->map
->edgey
[i
];
2881 ds
->todraw
[y
*w
+x
] |= ERR_BASE
<< (yo
*3+xo
);
2884 ds
->todraw
[y
*w
+(x
-1)] |= ERR_BASE
<< (yo
*3+2);
2888 ds
->todraw
[(y
-1)*w
+x
] |= ERR_BASE
<< (2*3+xo
);
2890 if (xo
== 0 && yo
== 0) {
2891 assert(x
> 0 && y
> 0);
2892 ds
->todraw
[(y
-1)*w
+(x
-1)] |= ERR_BASE
<< (2*3+2);
2897 * Now actually draw everything.
2899 for (y
= 0; y
< h
; y
++)
2900 for (x
= 0; x
< w
; x
++) {
2901 unsigned long v
= ds
->todraw
[y
*w
+x
];
2902 if (ds
->drawn
[y
*w
+x
] != v
) {
2903 draw_square(dr
, ds
, &state
->p
, state
->map
, x
, y
, v
);
2904 ds
->drawn
[y
*w
+x
] = v
;
2909 * Draw the dragged colour blob if any.
2911 if (ui
->drag_colour
> -2) {
2912 ds
->dragx
= ui
->dragx
- TILESIZE
/2 - 2;
2913 ds
->dragy
= ui
->dragy
- TILESIZE
/2 - 2;
2914 blitter_save(dr
, ds
->bl
, ds
->dragx
, ds
->dragy
);
2915 draw_circle(dr
, ui
->dragx
, ui
->dragy
, TILESIZE
/2,
2916 (ui
->drag_colour
< 0 ? COL_BACKGROUND
:
2917 COL_0
+ ui
->drag_colour
), COL_GRID
);
2918 for (i
= 0; i
< FOUR
; i
++)
2919 if (ui
->drag_pencil
& (1 << i
))
2920 draw_circle(dr
, ui
->dragx
+ ((i
*4+2)%10-3) * TILESIZE
/10,
2921 ui
->dragy
+ (i
*2-3) * TILESIZE
/10,
2922 TILESIZE
/8, COL_0
+ i
, COL_0
+ i
);
2923 draw_update(dr
, ds
->dragx
, ds
->dragy
, TILESIZE
+ 3, TILESIZE
+ 3);
2924 ds
->drag_visible
= TRUE
;
2928 static float game_anim_length(game_state
*oldstate
, game_state
*newstate
,
2929 int dir
, game_ui
*ui
)
2934 static float game_flash_length(game_state
*oldstate
, game_state
*newstate
,
2935 int dir
, game_ui
*ui
)
2937 if (!oldstate
->completed
&& newstate
->completed
&&
2938 !oldstate
->cheated
&& !newstate
->cheated
) {
2939 if (flash_type
< 0) {
2940 char *env
= getenv("MAP_ALTERNATIVE_FLASH");
2942 flash_type
= atoi(env
);
2945 flash_length
= (flash_type
== 1 ?
0.50 : 0.30);
2947 return flash_length
;
2952 static int game_timing_state(game_state
*state
, game_ui
*ui
)
2957 static void game_print_size(game_params
*params
, float *x
, float *y
)
2962 * I'll use 4mm squares by default, I think. Simplest way to
2963 * compute this size is to compute the pixel puzzle size at a
2964 * given tile size and then scale.
2966 game_compute_size(params
, 400, &pw
, &ph
);
2971 static void game_print(drawing
*dr
, game_state
*state
, int tilesize
)
2973 int w
= state
->p
.w
, h
= state
->p
.h
, wh
= w
*h
, n
= state
->p
.n
;
2974 int ink
, c
[FOUR
], i
;
2976 int *coords
, ncoords
, coordsize
;
2978 /* Ick: fake up `ds->tilesize' for macro expansion purposes */
2979 struct { int tilesize
; } ads
, *ds
= &ads
;
2980 /* We can't call game_set_size() here because we don't want a blitter */
2981 ads
.tilesize
= tilesize
;
2983 ink
= print_mono_colour(dr
, 0);
2984 for (i
= 0; i
< FOUR
; i
++)
2985 c
[i
] = print_rgb_hatched_colour(dr
, map_colours
[i
][0],
2986 map_colours
[i
][1], map_colours
[i
][2],
2992 print_line_width(dr
, TILESIZE
/ 16);
2995 * Draw a single filled polygon around each region.
2997 for (r
= 0; r
< n
; r
++) {
2998 int octants
[8], lastdir
, d1
, d2
, ox
, oy
;
3001 * Start by finding a point on the region boundary. Any
3002 * point will do. To do this, we'll search for a square
3003 * containing the region and then decide which corner of it
3007 for (y
= 0; y
< h
; y
++) {
3008 for (x
= 0; x
< w
; x
++) {
3009 if (state
->map
->map
[wh
*0+y
*w
+x
] == r
||
3010 state
->map
->map
[wh
*1+y
*w
+x
] == r
||
3011 state
->map
->map
[wh
*2+y
*w
+x
] == r
||
3012 state
->map
->map
[wh
*3+y
*w
+x
] == r
)
3018 assert(y
< h
&& x
< w
); /* we must have found one somewhere */
3020 * This is the first square in lexicographic order which
3021 * contains part of this region. Therefore, one of the top
3022 * two corners of the square must be what we're after. The
3023 * only case in which it isn't the top left one is if the
3024 * square is diagonally divided and the region is in the
3025 * bottom right half.
3027 if (state
->map
->map
[wh
*TE
+y
*w
+x
] != r
&&
3028 state
->map
->map
[wh
*LE
+y
*w
+x
] != r
)
3029 x
++; /* could just as well have done y++ */
3032 * Now we have a point on the region boundary. Trace around
3033 * the region until we come back to this point,
3034 * accumulating coordinates for a polygon draw operation as
3044 * There are eight possible directions we could head in
3045 * from here. We identify them by octant numbers, and
3046 * we also use octant numbers to identify the spaces
3059 octants
[0] = x
<w
&& y
>0 ? state
->map
->map
[wh
*LE
+(y
-1)*w
+x
] : -1;
3060 octants
[1] = x
<w
&& y
>0 ? state
->map
->map
[wh
*BE
+(y
-1)*w
+x
] : -1;
3061 octants
[2] = x
<w
&& y
<h ? state
->map
->map
[wh
*TE
+y
*w
+x
] : -1;
3062 octants
[3] = x
<w
&& y
<h ? state
->map
->map
[wh
*LE
+y
*w
+x
] : -1;
3063 octants
[4] = x
>0 && y
<h ? state
->map
->map
[wh
*RE
+y
*w
+(x
-1)] : -1;
3064 octants
[5] = x
>0 && y
<h ? state
->map
->map
[wh
*TE
+y
*w
+(x
-1)] : -1;
3065 octants
[6] = x
>0 && y
>0 ? state
->map
->map
[wh
*BE
+(y
-1)*w
+(x
-1)] :-1;
3066 octants
[7] = x
>0 && y
>0 ? state
->map
->map
[wh
*RE
+(y
-1)*w
+(x
-1)] :-1;
3069 for (i
= 0; i
< 8; i
++)
3070 if ((octants
[i
] == r
) ^ (octants
[(i
+1)%8] == r
)) {
3078 assert(d1
!= -1 && d2
!= -1);
3083 * Now we're heading in direction d1. Save the current
3086 if (ncoords
+ 2 > coordsize
) {
3088 coords
= sresize(coords
, coordsize
, int);
3090 coords
[ncoords
++] = COORD(x
);
3091 coords
[ncoords
++] = COORD(y
);
3094 * Compute the new coordinates.
3096 x
+= (d1
% 4 == 3 ?
0 : d1
< 4 ?
+1 : -1);
3097 y
+= (d1
% 4 == 1 ?
0 : d1
> 1 && d1
< 5 ?
+1 : -1);
3098 assert(x
>= 0 && x
<= w
&& y
>= 0 && y
<= h
);
3101 } while (x
!= ox
|| y
!= oy
);
3103 draw_polygon(dr
, coords
, ncoords
/2,
3104 state
->colouring
[r
] >= 0 ?
3105 c
[state
->colouring
[r
]] : -1, ink
);
3114 const struct game thegame
= {
3115 "Map", "games.map", "map",
3122 TRUE
, game_configure
, custom_params
,
3130 FALSE
, game_can_format_as_text_now
, game_text_format
,
3138 20, game_compute_size
, game_set_size
,
3141 game_free_drawstate
,
3145 TRUE
, TRUE
, game_print_size
, game_print
,
3146 FALSE
, /* wants_statusbar */
3147 FALSE
, game_timing_state
,
3151 #ifdef STANDALONE_SOLVER
3153 int main(int argc
, char **argv
)
3157 char *id
= NULL
, *desc
, *err
;
3159 int ret
, diff
, really_verbose
= FALSE
;
3160 struct solver_scratch
*sc
;
3163 while (--argc
> 0) {
3165 if (!strcmp(p
, "-v")) {
3166 really_verbose
= TRUE
;
3167 } else if (!strcmp(p
, "-g")) {
3169 } else if (*p
== '-') {
3170 fprintf(stderr
, "%s: unrecognised option `%s'\n", argv
[0], p
);
3178 fprintf(stderr
, "usage: %s [-g | -v] <game_id>\n", argv
[0]);
3182 desc
= strchr(id
, ':');
3184 fprintf(stderr
, "%s: game id expects a colon in it\n", argv
[0]);
3189 p
= default_params();
3190 decode_params(p
, id
);
3191 err
= validate_desc(p
, desc
);
3193 fprintf(stderr
, "%s: %s\n", argv
[0], err
);
3196 s
= new_game(NULL
, p
, desc
);
3198 sc
= new_scratch(s
->map
->graph
, s
->map
->n
, s
->map
->ngraph
);
3201 * When solving an Easy puzzle, we don't want to bother the
3202 * user with Hard-level deductions. For this reason, we grade
3203 * the puzzle internally before doing anything else.
3205 ret
= -1; /* placate optimiser */
3206 for (diff
= 0; diff
< DIFFCOUNT
; diff
++) {
3207 for (i
= 0; i
< s
->map
->n
; i
++)
3208 if (!s
->map
->immutable
[i
])
3209 s
->colouring
[i
] = -1;
3210 ret
= map_solver(sc
, s
->map
->graph
, s
->map
->n
, s
->map
->ngraph
,
3211 s
->colouring
, diff
);
3216 if (diff
== DIFFCOUNT
) {
3218 printf("Difficulty rating: harder than Hard, or ambiguous\n");
3220 printf("Unable to find a unique solution\n");
3224 printf("Difficulty rating: impossible (no solution exists)\n");
3226 printf("Difficulty rating: %s\n", map_diffnames
[diff
]);
3228 verbose
= really_verbose
;
3229 for (i
= 0; i
< s
->map
->n
; i
++)
3230 if (!s
->map
->immutable
[i
])
3231 s
->colouring
[i
] = -1;
3232 ret
= map_solver(sc
, s
->map
->graph
, s
->map
->n
, s
->map
->ngraph
,
3233 s
->colouring
, diff
);
3235 printf("Puzzle is inconsistent\n");
3239 for (i
= 0; i
< s
->map
->n
; i
++) {
3240 printf("%5d <- %c%c", i
, colnames
[s
->colouring
[i
]],
3241 (col
< 6 && i
+1 < s
->map
->n ?
' ' : '\n'));