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(origcolouring);
1377 sfree(subcolouring);
1380 #ifdef SOLVER_DIAGNOSTICS
1381 if (verbose && sc->depth == 0) {
1382 printf("%*s%s found\n",
1384 ret == 0 ? "no solutions" :
1385 ret == 1 ? "one solution" : "multiple solutions");
1392 /* ----------------------------------------------------------------------
1393 * Game generation main function.
1396 static char *new_game_desc(game_params *params, random_state *rs,
1397 char **aux, int interactive)
1399 struct solver_scratch *sc = NULL;
1400 int *map, *graph, ngraph, *colouring, *colouring2, *regions;
1401 int i, j, w, h, n, solveret, cfreq[FOUR];
1404 #ifdef GENERATION_DIAGNOSTICS
1408 int retlen, retsize;
1417 map = snewn(wh, int);
1418 graph = snewn(n*n, int);
1419 colouring = snewn(n, int);
1420 colouring2 = snewn(n, int);
1421 regions = snewn(n, int);
1424 * This is the minimum difficulty below which we'll completely
1425 * reject a map design. Normally we set this to one below the
1426 * requested difficulty, ensuring that we have the right
1427 * result. However, for particularly dense maps or maps with
1428 * particularly few regions it might not be possible to get the
1429 * desired difficulty, so we will eventually drop this down to
1430 * -1 to indicate that any old map will do.
1432 mindiff = params->diff;
1440 genmap(w, h, n, map, rs);
1442 #ifdef GENERATION_DIAGNOSTICS
1443 for (y = 0; y < h; y++) {
1444 for (x = 0; x < w; x++) {
1449 putchar('a' + v-36);
1451 putchar('A' + v-10);
1460 * Convert the map into a graph.
1462 ngraph = gengraph(w, h, n, map, graph);
1464 #ifdef GENERATION_DIAGNOSTICS
1465 for (i = 0; i < ngraph; i++)
1466 printf("%d-%d\n", graph[i]/n, graph[i]%n);
1472 fourcolour(graph, n, ngraph, colouring, rs);
1474 #ifdef GENERATION_DIAGNOSTICS
1475 for (i = 0; i < n; i++)
1476 printf("%d: %d\n", i, colouring[i]);
1478 for (y = 0; y < h; y++) {
1479 for (x = 0; x < w; x++) {
1480 int v = colouring[map[y*w+x]];
1482 putchar('a' + v-36);
1484 putchar('A' + v-10);
1493 * Encode the solution as an aux string.
1495 if (*aux) /* in case we've come round again */
1497 retlen = retsize = 0;
1499 for (i = 0; i < n; i++) {
1502 if (colouring[i] < 0)
1505 len = sprintf(buf, "%s%d:%d", i ? ";" : "S;", colouring[i], i);
1506 if (retlen + len >= retsize) {
1507 retsize = retlen + len + 256;
1508 ret = sresize(ret, retsize, char);
1510 strcpy(ret + retlen, buf);
1516 * Remove the region colours one by one, keeping
1517 * solubility. Also ensure that there always remains at
1518 * least one region of every colour, so that the user can
1519 * drag from somewhere.
1521 for (i = 0; i < FOUR; i++)
1523 for (i = 0; i < n; i++) {
1525 cfreq[colouring[i]]++;
1527 for (i = 0; i < FOUR; i++)
1531 shuffle(regions, n, sizeof(*regions), rs);
1533 if (sc) free_scratch(sc);
1534 sc = new_scratch(graph, n, ngraph);
1536 for (i = 0; i < n; i++) {
1539 if (cfreq[colouring[j]] == 1)
1540 continue; /* can't remove last region of colour */
1542 memcpy(colouring2, colouring, n*sizeof(int));
1544 solveret = map_solver(sc, graph, n, ngraph, colouring2,
1546 assert(solveret >= 0); /* mustn't be impossible! */
1547 if (solveret == 1) {
1548 cfreq[colouring[j]]--;
1553 #ifdef GENERATION_DIAGNOSTICS
1554 for (i = 0; i < n; i++)
1555 if (colouring[i] >= 0) {
1559 putchar('a' + i-36);
1561 putchar('A' + i-10);
1564 printf(": %d\n", colouring[i]);
1569 * Finally, check that the puzzle is _at least_ as hard as
1570 * required, and indeed that it isn't already solved.
1571 * (Calling map_solver with negative difficulty ensures the
1572 * latter - if a solver which _does nothing_ can solve it,
1575 memcpy(colouring2, colouring, n*sizeof(int));
1576 if (map_solver(sc, graph, n, ngraph, colouring2,
1577 mindiff - 1) == 1) {
1579 * Drop minimum difficulty if necessary.
1581 if (mindiff > 0 && (n < 9 || n > 2*wh/3)) {
1583 mindiff = 0; /* give up and go for Easy */
1592 * Encode as a game ID. We do this by:
1594 * - first going along the horizontal edges row by row, and
1595 * then the vertical edges column by column
1596 * - encoding the lengths of runs of edges and runs of
1598 * - the decoder will reconstitute the region boundaries from
1599 * this and automatically number them the same way we did
1600 * - then we encode the initial region colours in a Slant-like
1601 * fashion (digits 0-3 interspersed with letters giving
1602 * lengths of runs of empty spaces).
1604 retlen = retsize = 0;
1611 * Start with a notional non-edge, so that there'll be an
1612 * explicit `a' to distinguish the case where we start with
1618 for (i = 0; i < w*(h-1) + (w-1)*h; i++) {
1619 int x, y, dx, dy, v;
1622 /* Horizontal edge. */
1628 /* Vertical edge. */
1629 x = (i - w*(h-1)) / h;
1630 y = (i - w*(h-1)) % h;
1635 if (retlen + 10 >= retsize) {
1636 retsize = retlen + 256;
1637 ret = sresize(ret, retsize, char);
1640 v = (map[y*w+x] != map[(y+dy)*w+(x+dx)]);
1643 ret[retlen++] = 'a'-1 + run;
1648 * 'z' is a special case in this encoding. Rather
1649 * than meaning a run of 26 and a state switch, it
1650 * means a run of 25 and _no_ state switch, because
1651 * otherwise there'd be no way to encode runs of
1655 ret[retlen++] = 'z';
1662 ret[retlen++] = 'a'-1 + run;
1663 ret[retlen++] = ',';
1666 for (i = 0; i < n; i++) {
1667 if (retlen + 10 >= retsize) {
1668 retsize = retlen + 256;
1669 ret = sresize(ret, retsize, char);
1672 if (colouring[i] < 0) {
1674 * In _this_ encoding, 'z' is a run of 26, since
1675 * there's no implicit state switch after each run.
1676 * Confusingly different, but more compact.
1679 ret[retlen++] = 'z';
1685 ret[retlen++] = 'a'-1 + run;
1686 ret[retlen++] = '0' + colouring[i];
1691 ret[retlen++] = 'a'-1 + run;
1694 assert(retlen < retsize);
1707 static char *parse_edge_list(game_params *params, char **desc, int *map)
1709 int w = params->w, h = params->h, wh = w*h, n = params->n;
1710 int i, k, pos, state;
1713 dsf_init(map+wh, wh);
1719 * Parse the game description to get the list of edges, and
1720 * build up a disjoint set forest as we go (by identifying
1721 * pairs of squares whenever the edge list shows a non-edge).
1723 while (*p && *p != ',') {
1724 if (*p < 'a' || *p > 'z')
1725 return "Unexpected character in edge list";
1736 } else if (pos < w*(h-1)) {
1737 /* Horizontal edge. */
1742 } else if (pos < 2*wh-w-h) {
1743 /* Vertical edge. */
1744 x = (pos - w*(h-1)) / h;
1745 y = (pos - w*(h-1)) % h;
1749 return "Too much data in edge list";
1751 dsf_merge(map+wh, y*w+x, (y+dy)*w+(x+dx));
1759 assert(pos <= 2*wh-w-h);
1761 return "Too little data in edge list";
1764 * Now go through again and allocate region numbers.
1767 for (i = 0; i < wh; i++)
1769 for (i = 0; i < wh; i++) {
1770 k = dsf_canonify(map+wh, i);
1776 return "Edge list defines the wrong number of regions";
1783 static char *validate_desc(game_params *params, char *desc)
1785 int w = params->w, h = params->h, wh = w*h, n = params->n;
1790 map = snewn(2*wh, int);
1791 ret = parse_edge_list(params, &desc, map);
1797 return "Expected comma before clue list";
1798 desc++; /* eat comma */
1802 if (*desc >= '0' && *desc < '0'+FOUR)
1804 else if (*desc >= 'a' && *desc <= 'z')
1805 area += *desc - 'a' + 1;
1807 return "Unexpected character in clue list";
1811 return "Too little data in clue list";
1813 return "Too much data in clue list";
1818 static game_state *new_game(midend *me, game_params *params, char *desc)
1820 int w = params->w, h = params->h, wh = w*h, n = params->n;
1823 game_state *state = snew(game_state);
1826 state->colouring = snewn(n, int);
1827 for (i = 0; i < n; i++)
1828 state->colouring[i] = -1;
1829 state->pencil = snewn(n, int);
1830 for (i = 0; i < n; i++)
1831 state->pencil[i] = 0;
1833 state->completed = state->cheated = FALSE;
1835 state->map = snew(struct map);
1836 state->map->refcount = 1;
1837 state->map->map = snewn(wh*4, int);
1838 state->map->graph = snewn(n*n, int);
1840 state->map->immutable = snewn(n, int);
1841 for (i = 0; i < n; i++)
1842 state->map->immutable[i] = FALSE;
1848 ret = parse_edge_list(params, &p, state->map->map);
1853 * Set up the other three quadrants in `map'.
1855 for (i = wh; i < 4*wh; i++)
1856 state->map->map[i] = state->map->map[i % wh];
1862 * Now process the clue list.
1866 if (*p >= '0' && *p < '0'+FOUR) {
1867 state->colouring[pos] = *p - '0';
1868 state->map->immutable[pos] = TRUE;
1871 assert(*p >= 'a' && *p <= 'z');
1872 pos += *p - 'a' + 1;
1878 state->map->ngraph = gengraph(w, h, n, state->map->map, state->map->graph);
1881 * Attempt to smooth out some of the more jagged region
1882 * outlines by the judicious use of diagonally divided squares.
1885 random_state *rs = random_new(desc, strlen(desc));
1886 int *squares = snewn(wh, int);
1889 for (i = 0; i < wh; i++)
1891 shuffle(squares, wh, sizeof(*squares), rs);
1894 done_something = FALSE;
1895 for (i = 0; i < wh; i++) {
1896 int y = squares[i] / w, x = squares[i] % w;
1897 int c = state->map->map[y*w+x];
1900 if (x == 0 || x == w-1 || y == 0 || y == h-1)
1903 if (state->map->map[TE * wh + y*w+x] !=
1904 state->map->map[BE * wh + y*w+x])
1907 tc = state->map->map[BE * wh + (y-1)*w+x];
1908 bc = state->map->map[TE * wh + (y+1)*w+x];
1909 lc = state->map->map[RE * wh + y*w+(x-1)];
1910 rc = state->map->map[LE * wh + y*w+(x+1)];
1913 * If this square is adjacent on two sides to one
1914 * region and on the other two sides to the other
1915 * region, and is itself one of the two regions, we can
1916 * adjust it so that it's a diagonal.
1918 if (tc != bc && (tc == c || bc == c)) {
1919 if ((lc == tc && rc == bc) ||
1920 (lc == bc && rc == tc)) {
1921 state->map->map[TE * wh + y*w+x] = tc;
1922 state->map->map[BE * wh + y*w+x] = bc;
1923 state->map->map[LE * wh + y*w+x] = lc;
1924 state->map->map[RE * wh + y*w+x] = rc;
1925 done_something = TRUE;
1929 } while (done_something);
1935 * Analyse the map to find a canonical line segment
1936 * corresponding to each edge, and a canonical point
1937 * corresponding to each region. The former are where we'll
1938 * eventually put error markers; the latter are where we'll put
1939 * per-region flags such as numbers (when in diagnostic mode).
1942 int *bestx, *besty, *an, pass;
1943 float *ax, *ay, *best;
1945 ax = snewn(state->map->ngraph + n, float);
1946 ay = snewn(state->map->ngraph + n, float);
1947 an = snewn(state->map->ngraph + n, int);
1948 bestx = snewn(state->map->ngraph + n, int);
1949 besty = snewn(state->map->ngraph + n, int);
1950 best = snewn(state->map->ngraph + n, float);
1952 for (i = 0; i < state->map->ngraph + n; i++) {
1953 bestx[i] = besty[i] = -1;
1954 best[i] = (float)(2*(w+h)+1);
1955 ax[i] = ay[i] = 0.0F;
1960 * We make two passes over the map, finding all the line
1961 * segments separating regions and all the suitable points
1962 * within regions. In the first pass, we compute the
1963 * _average_ x and y coordinate of all the points in a
1964 * given class; in the second pass, for each such average
1965 * point, we find the candidate closest to it and call that
1968 * Line segments are considered to have coordinates in
1969 * their centre. Thus, at least one coordinate for any line
1970 * segment is always something-and-a-half; so we store our
1971 * coordinates as twice their normal value.
1973 for (pass = 0; pass < 2; pass++) {
1976 for (y = 0; y < h; y++)
1977 for (x = 0; x < w; x++) {
1978 int ex[4], ey[4], ea[4], eb[4], en = 0;
1981 * Look for an edge to the right of this
1982 * square, an edge below it, and an edge in the
1983 * middle of it. Also look to see if the point
1984 * at the bottom right of this square is on an
1985 * edge (and isn't a place where more than two
1990 ea[en] = state->map->map[RE * wh + y*w+x];
1991 eb[en] = state->map->map[LE * wh + y*w+(x+1)];
1998 ea[en] = state->map->map[BE * wh + y*w+x];
1999 eb[en] = state->map->map[TE * wh + (y+1)*w+x];
2005 ea[en] = state->map->map[TE * wh + y*w+x];
2006 eb[en] = state->map->map[BE * wh + y*w+x];
2011 if (x+1 < w && y+1 < h) {
2012 /* bottom right corner */
2013 int oct[8], othercol, nchanges;
2014 oct[0] = state->map->map[RE * wh + y*w+x];
2015 oct[1] = state->map->map[LE * wh + y*w+(x+1)];
2016 oct[2] = state->map->map[BE * wh + y*w+(x+1)];
2017 oct[3] = state->map->map[TE * wh + (y+1)*w+(x+1)];
2018 oct[4] = state->map->map[LE * wh + (y+1)*w+(x+1)];
2019 oct[5] = state->map->map[RE * wh + (y+1)*w+x];
2020 oct[6] = state->map->map[TE * wh + (y+1)*w+x];
2021 oct[7] = state->map->map[BE * wh + y*w+x];
2025 for (i = 0; i < 8; i++) {
2026 if (oct[i] != oct[0]) {
2029 else if (othercol != oct[i])
2030 break; /* three colours at this point */
2032 if (oct[i] != oct[(i+1) & 7])
2037 * Now if there are exactly two regions at
2038 * this point (not one, and not three or
2039 * more), and only two changes around the
2040 * loop, then this is a valid place to put
2043 if (i == 8 && othercol >= 0 && nchanges == 2) {
2052 * If there's exactly _one_ region at this
2053 * point, on the other hand, it's a valid
2054 * place to put a region centre.
2057 ea[en] = eb[en] = oct[0];
2065 * Now process the points we've found, one by
2068 for (i = 0; i < en; i++) {
2069 int emin = min(ea[i], eb[i]);
2070 int emax = max(ea[i], eb[i]);
2076 graph_edge_index(state->map->graph, n,
2077 state->map->ngraph, emin,
2081 gindex = state->map->ngraph + emin;
2084 assert(gindex >= 0);
2088 * In pass 0, accumulate the values
2089 * we'll use to compute the average
2092 ax[gindex] += ex[i];
2093 ay[gindex] += ey[i];
2097 * In pass 1, work out whether this
2098 * point is closer to the average than
2099 * the last one we've seen.
2103 assert(an[gindex] > 0);
2104 dx = ex[i] - ax[gindex];
2105 dy = ey[i] - ay[gindex];
2106 d = (float)sqrt(dx*dx + dy*dy);
2107 if (d < best[gindex]) {
2109 bestx[gindex] = ex[i];
2110 besty[gindex] = ey[i];
2117 for (i = 0; i < state->map->ngraph + n; i++)
2125 state->map->edgex = snewn(state->map->ngraph, int);
2126 state->map->edgey = snewn(state->map->ngraph, int);
2127 memcpy(state->map->edgex, bestx, state->map->ngraph * sizeof(int));
2128 memcpy(state->map->edgey, besty, state->map->ngraph * sizeof(int));
2130 state->map->regionx = snewn(n, int);
2131 state->map->regiony = snewn(n, int);
2132 memcpy(state->map->regionx, bestx + state->map->ngraph, n*sizeof(int));
2133 memcpy(state->map->regiony, besty + state->map->ngraph, n*sizeof(int));
2135 for (i = 0; i < state->map->ngraph; i++)
2136 if (state->map->edgex[i] < 0) {
2137 /* Find the other representation of this edge. */
2138 int e = state->map->graph[i];
2139 int iprime = graph_edge_index(state->map->graph, n,
2140 state->map->ngraph, e%n, e/n);
2141 assert(state->map->edgex[iprime] >= 0);
2142 state->map->edgex[i] = state->map->edgex[iprime];
2143 state->map->edgey[i] = state->map->edgey[iprime];
2157 static game_state *dup_game(game_state *state)
2159 game_state *ret = snew(game_state);
2162 ret->colouring = snewn(state->p.n, int);
2163 memcpy(ret->colouring, state->colouring, state->p.n * sizeof(int));
2164 ret->pencil = snewn(state->p.n, int);
2165 memcpy(ret->pencil, state->pencil, state->p.n * sizeof(int));
2166 ret->map = state->map;
2167 ret->map->refcount++;
2168 ret->completed = state->completed;
2169 ret->cheated = state->cheated;
2174 static void free_game(game_state *state)
2176 if (--state->map->refcount <= 0) {
2177 sfree(state->map->map);
2178 sfree(state->map->graph);
2179 sfree(state->map->immutable);
2180 sfree(state->map->edgex);
2181 sfree(state->map->edgey);
2182 sfree(state->map->regionx);
2183 sfree(state->map->regiony);
2186 sfree(state->pencil);
2187 sfree(state->colouring);
2191 static char *solve_game(game_state *state, game_state *currstate,
2192 char *aux, char **error)
2199 struct solver_scratch *sc;
2203 int retlen, retsize;
2205 colouring = snewn(state->map->n, int);
2206 memcpy(colouring, state->colouring, state->map->n * sizeof(int));
2208 sc = new_scratch(state->map->graph, state->map->n, state->map->ngraph);
2209 sret = map_solver(sc, state->map->graph, state->map->n,
2210 state->map->ngraph, colouring, DIFFCOUNT-1);
2216 *error = "Puzzle is inconsistent";
2218 *error = "Unable to find a unique solution for this puzzle";
2223 ret = snewn(retsize, char);
2227 for (i = 0; i < state->map->n; i++) {
2230 assert(colouring[i] >= 0);
2231 if (colouring[i] == currstate->colouring[i])
2233 assert(!state->map->immutable[i]);
2235 len = sprintf(buf, ";%d:%d", colouring[i], i);
2236 if (retlen + len >= retsize) {
2237 retsize = retlen + len + 256;
2238 ret = sresize(ret, retsize, char);
2240 strcpy(ret + retlen, buf);
2251 static int game_can_format_as_text_now(game_params *params)
2256 static char *game_text_format(game_state *state)
2265 * - -2 means no drag currently active.
2266 * - >=0 means we're dragging a solid colour.
2267 * - -1 means we're dragging a blank space, and drag_pencil
2268 * might or might not add some pencil-mark stipples to that.
2275 int cur_x, cur_y, cur_visible, cur_moved, cur_lastmove;
2278 static game_ui *new_ui(game_state *state)
2280 game_ui *ui = snew(game_ui);
2281 ui->dragx = ui->dragy = -1;
2282 ui->drag_colour = -2;
2283 ui->drag_pencil = 0;
2284 ui->show_numbers = FALSE;
2285 ui->cur_x = ui->cur_y = ui->cur_visible = ui->cur_moved = 0;
2286 ui->cur_lastmove = 0;
2290 static void free_ui(game_ui *ui)
2295 static char *encode_ui(game_ui *ui)
2300 static void decode_ui(game_ui *ui, char *encoding)
2304 static void game_changed_state(game_ui *ui, game_state *oldstate,
2305 game_state *newstate)
2309 struct game_drawstate {
2311 unsigned long *drawn, *todraw;
2313 int dragx, dragy, drag_visible;
2317 /* Flags in `drawn'. */
2318 #define ERR_BASE 0x00800000L
2319 #define ERR_MASK 0xFF800000L
2320 #define PENCIL_T_BASE 0x00080000L
2321 #define PENCIL_T_MASK 0x00780000L
2322 #define PENCIL_B_BASE 0x00008000L
2323 #define PENCIL_B_MASK 0x00078000L
2324 #define PENCIL_MASK 0x007F8000L
2325 #define SHOW_NUMBERS 0x00004000L
2327 #define TILESIZE (ds->tilesize)
2328 #define BORDER (TILESIZE)
2329 #define COORD(x) ( (x) * TILESIZE + BORDER )
2330 #define FROMCOORD(x) ( ((x) - BORDER + TILESIZE) / TILESIZE - 1 )
2333 * EPSILON_FOO are epsilons added to absolute cursor position by
2334 * cursor movement, such that in pathological cases (e.g. a very
2335 * small diamond-shaped area) it's relatively easy to select the
2336 * region you wanted.
2339 #define EPSILON_X(button) (((button) == CURSOR_RIGHT) ? +1 : \
2340 ((button) == CURSOR_LEFT) ? -1 : 0)
2341 #define EPSILON_Y(button) (((button) == CURSOR_DOWN) ? +1 : \
2342 ((button) == CURSOR_UP) ? -1 : 0)
2345 static int region_from_coords(game_state *state, game_drawstate *ds,
2348 int w = state->p.w, h = state->p.h, wh = w*h /*, n = state->p.n */;
2349 int tx = FROMCOORD(x), ty = FROMCOORD(y);
2350 int dx = x - COORD(tx), dy = y - COORD(ty);
2353 if (tx < 0 || tx >= w || ty < 0 || ty >= h)
2354 return -1; /* border */
2356 quadrant = 2 * (dx > dy) + (TILESIZE - dx > dy);
2357 quadrant = (quadrant == 0 ? BE :
2358 quadrant == 1 ? LE :
2359 quadrant == 2 ? RE : TE);
2361 return state->map->map[quadrant * wh + ty*w+tx];
2364 static char *interpret_move(game_state *state, game_ui *ui, game_drawstate *ds,
2365 int x, int y, int button)
2367 char *bufp, buf[256];
2371 * Enable or disable numeric labels on regions.
2373 if (button == 'l' || button == 'L') {
2374 ui->show_numbers = !ui->show_numbers;
2378 if (IS_CURSOR_MOVE(button)) {
2379 move_cursor(button, &ui->cur_x, &ui->cur_y, state->p.w, state->p.h, 0);
2380 ui->cur_visible = 1;
2382 ui->cur_lastmove = button;
2383 ui->dragx = COORD(ui->cur_x) + TILESIZE/2 + EPSILON_X(button);
2384 ui->dragy = COORD(ui->cur_y) + TILESIZE/2 + EPSILON_Y(button);
2387 if (IS_CURSOR_SELECT(button)) {
2388 if (!ui->cur_visible) {
2389 ui->dragx = COORD(ui->cur_x) + TILESIZE/2 + EPSILON_X(ui->cur_lastmove);
2390 ui->dragy = COORD(ui->cur_y) + TILESIZE/2 + EPSILON_Y(ui->cur_lastmove);
2391 ui->cur_visible = 1;
2394 if (ui->drag_colour == -2) { /* not currently cursor-dragging, start. */
2395 int r = region_from_coords(state, ds, ui->dragx, ui->dragy);
2397 ui->drag_colour = state->colouring[r];
2398 ui->drag_pencil = (ui->drag_colour >= 0) ? 0 : state->pencil[r];
2400 ui->drag_colour = -1;
2401 ui->drag_pencil = 0;
2405 } else { /* currently cursor-dragging; drop the colour in the new region. */
2406 x = COORD(ui->cur_x) + TILESIZE/2 + EPSILON_X(ui->cur_lastmove);
2407 y = COORD(ui->cur_y) + TILESIZE/2 + EPSILON_Y(ui->cur_lastmove);
2408 alt_button = (button == CURSOR_SELECT2) ? 1 : 0;
2409 /* Double-select removes current colour. */
2410 if (!ui->cur_moved) ui->drag_colour = -1;
2415 if (button == LEFT_BUTTON || button == RIGHT_BUTTON) {
2416 int r = region_from_coords(state, ds, x, y);
2419 ui->drag_colour = state->colouring[r];
2420 ui->drag_pencil = state->pencil[r];
2421 if (ui->drag_colour >= 0)
2422 ui->drag_pencil = 0; /* should be already, but double-check */
2424 ui->drag_colour = -1;
2425 ui->drag_pencil = 0;
2429 ui->cur_visible = 0;
2433 if ((button == LEFT_DRAG || button == RIGHT_DRAG) &&
2434 ui->drag_colour > -2) {
2440 if ((button == LEFT_RELEASE || button == RIGHT_RELEASE) &&
2441 ui->drag_colour > -2) {
2442 alt_button = (button == RIGHT_RELEASE) ? 1 : 0;
2450 int r = region_from_coords(state, ds, x, y);
2451 int c = ui->drag_colour;
2452 int p = ui->drag_pencil;
2456 * Cancel the drag, whatever happens.
2458 ui->drag_colour = -2;
2461 return ""; /* drag into border; do nothing else */
2463 if (state->map->immutable[r])
2464 return ""; /* can't change this region */
2466 if (state->colouring[r] == c && state->pencil[r] == p)
2467 return ""; /* don't _need_ to change this region */
2470 if (state->colouring[r] >= 0) {
2471 /* Can't pencil on a coloured region */
2473 } else if (c >= 0) {
2474 /* Right-dragging from colour to blank toggles one pencil */
2475 p = state->pencil[r] ^ (1 << c);
2478 /* Otherwise, right-dragging from blank to blank is equivalent
2479 * to left-dragging. */
2483 oldp = state->pencil[r];
2484 if (c != state->colouring[r]) {
2485 bufp += sprintf(bufp, ";%c:%d", (int)(c < 0 ? 'C' : '0' + c), r);
2491 for (i = 0; i < FOUR; i++)
2492 if ((oldp ^ p) & (1 << i))
2493 bufp += sprintf(bufp, ";p%c:%d", (int)('0' + i), r);
2496 return dupstr(buf+1); /* ignore first semicolon */
2500 static game_state *execute_move(game_state *state, char *move)
2503 game_state *ret = dup_game(state);
2514 if ((c == 'C' || (c >= '0' && c < '0'+FOUR)) &&
2515 sscanf(move+1, ":%d%n", &k, &adv) == 1 &&
2516 k >= 0 && k < state->p.n) {
2519 if (ret->colouring[k] >= 0) {
2526 ret->pencil[k] ^= 1 << (c - '0');
2528 ret->colouring[k] = (c == 'C' ? -1 : c - '0');
2531 } else if (*move == 'S') {
2533 ret->cheated = TRUE;
2539 if (*move && *move != ';') {
2548 * Check for completion.
2550 if (!ret->completed) {
2553 for (i = 0; i < n; i++)
2554 if (ret->colouring[i] < 0) {
2560 for (i = 0; i < ret->map->ngraph; i++) {
2561 int j = ret->map->graph[i] / n;
2562 int k = ret->map->graph[i] % n;
2563 if (ret->colouring[j] == ret->colouring[k]) {
2571 ret->completed = TRUE;
2577 /* ----------------------------------------------------------------------
2581 static void game_compute_size(game_params *params, int tilesize,
2584 /* Ick: fake up `ds->tilesize' for macro expansion purposes */
2585 struct { int tilesize; } ads, *ds = &ads;
2586 ads.tilesize = tilesize;
2588 *x = params->w * TILESIZE + 2 * BORDER + 1;
2589 *y = params->h * TILESIZE + 2 * BORDER + 1;
2592 static void game_set_size(drawing *dr, game_drawstate *ds,
2593 game_params *params, int tilesize)
2595 ds->tilesize = tilesize;
2597 assert(!ds->bl); /* set_size is never called twice */
2598 ds->bl = blitter_new(dr, TILESIZE+3, TILESIZE+3);
2601 const float map_colours[FOUR][3] = {
2602 #ifdef VIVID_COLOURS
2603 /* Use more vivid colours (e.g. on the Pocket PC) */
2604 {0.75F, 0.25F, 0.25F},
2607 {0.85F, 0.85F, 0.1F},
2612 {0.55F, 0.45F, 0.35F},
2615 const int map_hatching[FOUR] = {
2616 HATCH_VERT, HATCH_SLASH, HATCH_HORIZ, HATCH_BACKSLASH
2619 static float *game_colours(frontend *fe, int *ncolours)
2621 float *ret = snewn(3 * NCOLOURS, float);
2623 frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]);
2625 ret[COL_GRID * 3 + 0] = 0.0F;
2626 ret[COL_GRID * 3 + 1] = 0.0F;
2627 ret[COL_GRID * 3 + 2] = 0.0F;
2629 memcpy(ret + COL_0 * 3, map_colours[0], 3 * sizeof(float));
2630 memcpy(ret + COL_1 * 3, map_colours[1], 3 * sizeof(float));
2631 memcpy(ret + COL_2 * 3, map_colours[2], 3 * sizeof(float));
2632 memcpy(ret + COL_3 * 3, map_colours[3], 3 * sizeof(float));
2634 ret[COL_ERROR * 3 + 0] = 1.0F;
2635 ret[COL_ERROR * 3 + 1] = 0.0F;
2636 ret[COL_ERROR * 3 + 2] = 0.0F;
2638 ret[COL_ERRTEXT * 3 + 0] = 1.0F;
2639 ret[COL_ERRTEXT * 3 + 1] = 1.0F;
2640 ret[COL_ERRTEXT * 3 + 2] = 1.0F;
2642 *ncolours = NCOLOURS;
2646 static game_drawstate *game_new_drawstate(drawing *dr, game_state *state)
2648 struct game_drawstate *ds = snew(struct game_drawstate);
2652 ds->drawn = snewn(state->p.w * state->p.h, unsigned long);
2653 for (i = 0; i < state->p.w * state->p.h; i++)
2654 ds->drawn[i] = 0xFFFFL;
2655 ds->todraw = snewn(state->p.w * state->p.h, unsigned long);
2656 ds->started = FALSE;
2658 ds->drag_visible = FALSE;
2659 ds->dragx = ds->dragy = -1;
2664 static void game_free_drawstate(drawing *dr, game_drawstate *ds)
2669 blitter_free(dr, ds->bl);
2673 static void draw_error(drawing *dr, game_drawstate *ds, int x, int y)
2681 coords[0] = x - TILESIZE*2/5;
2684 coords[3] = y - TILESIZE*2/5;
2685 coords[4] = x + TILESIZE*2/5;
2688 coords[7] = y + TILESIZE*2/5;
2689 draw_polygon(dr, coords, 4, COL_ERROR, COL_GRID);
2692 * Draw an exclamation mark in the diamond. This turns out to
2693 * look unpleasantly off-centre if done via draw_text, so I do
2694 * it by hand on the basis that exclamation marks aren't that
2695 * difficult to draw...
2698 yext = TILESIZE*2/5 - (xext*2+2);
2699 draw_rect(dr, x-xext, y-yext, xext*2+1, yext*2+1 - (xext*3),
2701 draw_rect(dr, x-xext, y+yext-xext*2+1, xext*2+1, xext*2, COL_ERRTEXT);
2704 static void draw_square(drawing *dr, game_drawstate *ds,
2705 game_params *params, struct map *map,
2706 int x, int y, unsigned long v)
2708 int w = params->w, h = params->h, wh = w*h;
2709 int tv, bv, xo, yo, i, j, oldj;
2710 unsigned long errs, pencil, show_numbers;
2712 errs = v & ERR_MASK;
2714 pencil = v & PENCIL_MASK;
2716 show_numbers = v & SHOW_NUMBERS;
2721 clip(dr, COORD(x), COORD(y), TILESIZE, TILESIZE);
2724 * Draw the region colour.
2726 draw_rect(dr, COORD(x), COORD(y), TILESIZE, TILESIZE,
2727 (tv == FOUR ? COL_BACKGROUND : COL_0 + tv));
2729 * Draw the second region colour, if this is a diagonally
2732 if (map->map[TE * wh + y*w+x] != map->map[BE * wh + y*w+x]) {
2734 coords[0] = COORD(x)-1;
2735 coords[1] = COORD(y+1)+1;
2736 if (map->map[LE * wh + y*w+x] == map->map[TE * wh + y*w+x])
2737 coords[2] = COORD(x+1)+1;
2739 coords[2] = COORD(x)-1;
2740 coords[3] = COORD(y)-1;
2741 coords[4] = COORD(x+1)+1;
2742 coords[5] = COORD(y+1)+1;
2743 draw_polygon(dr, coords, 3,
2744 (bv == FOUR ? COL_BACKGROUND : COL_0 + bv), COL_GRID);
2748 * Draw `pencil marks'. Currently we arrange these in a square
2749 * formation, which means we may be in trouble if the value of
2750 * FOUR changes later...
2753 for (yo = 0; yo < 4; yo++)
2754 for (xo = 0; xo < 4; xo++) {
2755 int te = map->map[TE * wh + y*w+x];
2758 e = (yo < xo && yo < 3-xo ? TE :
2759 yo > xo && yo > 3-xo ? BE :
2761 ee = map->map[e * wh + y*w+x];
2763 if (xo != (yo * 2 + 1) % 5)
2767 if (!(pencil & ((ee == te ? PENCIL_T_BASE : PENCIL_B_BASE) << c)))
2771 (map->map[TE * wh + y*w+x] != map->map[LE * wh + y*w+x]))
2772 continue; /* avoid TL-BR diagonal line */
2774 (map->map[TE * wh + y*w+x] != map->map[RE * wh + y*w+x]))
2775 continue; /* avoid BL-TR diagonal line */
2777 draw_circle(dr, COORD(x) + (xo+1)*TILESIZE/5,
2778 COORD(y) + (yo+1)*TILESIZE/5,
2779 TILESIZE/7, COL_0 + c, COL_0 + c);
2783 * Draw the grid lines, if required.
2785 if (x <= 0 || map->map[RE*wh+y*w+(x-1)] != map->map[LE*wh+y*w+x])
2786 draw_rect(dr, COORD(x), COORD(y), 1, TILESIZE, COL_GRID);
2787 if (y <= 0 || map->map[BE*wh+(y-1)*w+x] != map->map[TE*wh+y*w+x])
2788 draw_rect(dr, COORD(x), COORD(y), TILESIZE, 1, COL_GRID);
2789 if (x <= 0 || y <= 0 ||
2790 map->map[RE*wh+(y-1)*w+(x-1)] != map->map[TE*wh+y*w+x] ||
2791 map->map[BE*wh+(y-1)*w+(x-1)] != map->map[LE*wh+y*w+x])
2792 draw_rect(dr, COORD(x), COORD(y), 1, 1, COL_GRID);
2795 * Draw error markers.
2797 for (yo = 0; yo < 3; yo++)
2798 for (xo = 0; xo < 3; xo++)
2799 if (errs & (ERR_BASE << (yo*3+xo)))
2801 (COORD(x)*2+TILESIZE*xo)/2,
2802 (COORD(y)*2+TILESIZE*yo)/2);
2805 * Draw region numbers, if desired.
2809 for (i = 0; i < 2; i++) {
2810 j = map->map[(i?BE:TE)*wh+y*w+x];
2815 xo = map->regionx[j] - 2*x;
2816 yo = map->regiony[j] - 2*y;
2817 if (xo >= 0 && xo <= 2 && yo >= 0 && yo <= 2) {
2819 sprintf(buf, "%d", j);
2820 draw_text(dr, (COORD(x)*2+TILESIZE*xo)/2,
2821 (COORD(y)*2+TILESIZE*yo)/2,
2822 FONT_VARIABLE, 3*TILESIZE/5,
2823 ALIGN_HCENTRE|ALIGN_VCENTRE,
2831 draw_update(dr, COORD(x), COORD(y), TILESIZE, TILESIZE);
2834 static void game_redraw(drawing *dr, game_drawstate *ds, game_state *oldstate,
2835 game_state *state, int dir, game_ui *ui,
2836 float animtime, float flashtime)
2838 int w = state->p.w, h = state->p.h, wh = w*h, n = state->p.n;
2842 if (ds->drag_visible) {
2843 blitter_load(dr, ds->bl, ds->dragx, ds->dragy);
2844 draw_update(dr, ds->dragx, ds->dragy, TILESIZE + 3, TILESIZE + 3);
2845 ds->drag_visible = FALSE;
2849 * The initial contents of the window are not guaranteed and
2850 * can vary with front ends. To be on the safe side, all games
2851 * should start by drawing a big background-colour rectangle
2852 * covering the whole window.
2857 game_compute_size(&state->p, TILESIZE, &ww, &wh);
2858 draw_rect(dr, 0, 0, ww, wh, COL_BACKGROUND);
2859 draw_rect(dr, COORD(0), COORD(0), w*TILESIZE+1, h*TILESIZE+1,
2862 draw_update(dr, 0, 0, ww, wh);
2867 if (flash_type == 1)
2868 flash = (int)(flashtime * FOUR / flash_length);
2870 flash = 1 + (int)(flashtime * THREE / flash_length);
2875 * Set up the `todraw' array.
2877 for (y = 0; y < h; y++)
2878 for (x = 0; x < w; x++) {
2879 int tv = state->colouring[state->map->map[TE * wh + y*w+x]];
2880 int bv = state->colouring[state->map->map[BE * wh + y*w+x]];
2889 if (flash_type == 1) {
2894 } else if (flash_type == 2) {
2899 tv = (tv + flash) % FOUR;
2901 bv = (bv + flash) % FOUR;
2910 for (i = 0; i < FOUR; i++) {
2911 if (state->colouring[state->map->map[TE * wh + y*w+x]] < 0 &&
2912 (state->pencil[state->map->map[TE * wh + y*w+x]] & (1<<i)))
2913 v |= PENCIL_T_BASE << i;
2914 if (state->colouring[state->map->map[BE * wh + y*w+x]] < 0 &&
2915 (state->pencil[state->map->map[BE * wh + y*w+x]] & (1<<i)))
2916 v |= PENCIL_B_BASE << i;
2919 if (ui->show_numbers)
2922 ds->todraw[y*w+x] = v;
2926 * Add error markers to the `todraw' array.
2928 for (i = 0; i < state->map->ngraph; i++) {
2929 int v1 = state->map->graph[i] / n;
2930 int v2 = state->map->graph[i] % n;
2933 if (state->colouring[v1] < 0 || state->colouring[v2] < 0)
2935 if (state->colouring[v1] != state->colouring[v2])
2938 x = state->map->edgex[i];
2939 y = state->map->edgey[i];
2944 ds->todraw[y*w+x] |= ERR_BASE << (yo*3+xo);
2947 ds->todraw[y*w+(x-1)] |= ERR_BASE << (yo*3+2);
2951 ds->todraw[(y-1)*w+x] |= ERR_BASE << (2*3+xo);
2953 if (xo == 0 && yo == 0) {
2954 assert(x > 0 && y > 0);
2955 ds->todraw[(y-1)*w+(x-1)] |= ERR_BASE << (2*3+2);
2960 * Now actually draw everything.
2962 for (y = 0; y < h; y++)
2963 for (x = 0; x < w; x++) {
2964 unsigned long v = ds->todraw[y*w+x];
2965 if (ds->drawn[y*w+x] != v) {
2966 draw_square(dr, ds, &state->p, state->map, x, y, v);
2967 ds->drawn[y*w+x] = v;
2972 * Draw the dragged colour blob if any.
2974 if ((ui->drag_colour > -2) || ui->cur_visible) {
2976 if (ui->drag_colour >= 0)
2977 bg = COL_0 + ui->drag_colour;
2978 else if (ui->drag_colour == -1) {
2979 bg = COL_BACKGROUND;
2981 int r = region_from_coords(state, ds, ui->dragx, ui->dragy);
2982 int c = (r < 0) ? -1 : state->colouring[r];
2983 assert(ui->cur_visible);
2985 bg = (c < 0) ? COL_BACKGROUND : COL_0 + c;
2989 ds->dragx = ui->dragx - TILESIZE/2 - 2;
2990 ds->dragy = ui->dragy - TILESIZE/2 - 2;
2991 blitter_save(dr, ds->bl, ds->dragx, ds->dragy);
2992 draw_circle(dr, ui->dragx, ui->dragy,
2993 iscur ? TILESIZE/4 : TILESIZE/2, bg, COL_GRID);
2994 for (i = 0; i < FOUR; i++)
2995 if (ui->drag_pencil & (1 << i))
2996 draw_circle(dr, ui->dragx + ((i*4+2)%10-3) * TILESIZE/10,
2997 ui->dragy + (i*2-3) * TILESIZE/10,
2998 TILESIZE/8, COL_0 + i, COL_0 + i);
2999 draw_update(dr, ds->dragx, ds->dragy, TILESIZE + 3, TILESIZE + 3);
3000 ds->drag_visible = TRUE;
3004 static float game_anim_length(game_state *oldstate, game_state *newstate,
3005 int dir, game_ui *ui)
3010 static float game_flash_length(game_state *oldstate, game_state *newstate,
3011 int dir, game_ui *ui)
3013 if (!oldstate->completed && newstate->completed &&
3014 !oldstate->cheated && !newstate->cheated) {
3015 if (flash_type < 0) {
3016 char *env = getenv("MAP_ALTERNATIVE_FLASH");
3018 flash_type = atoi(env);
3021 flash_length = (flash_type == 1 ? 0.50F : 0.30F);
3023 return flash_length;
3028 static int game_timing_state(game_state *state, game_ui *ui)
3033 static void game_print_size(game_params *params, float *x, float *y)
3038 * I'll use 4mm squares by default, I think. Simplest way to
3039 * compute this size is to compute the pixel puzzle size at a
3040 * given tile size and then scale.
3042 game_compute_size(params, 400, &pw, &ph);
3047 static void game_print(drawing *dr, game_state *state, int tilesize)
3049 int w = state->p.w, h = state->p.h, wh = w*h, n = state->p.n;
3050 int ink, c[FOUR], i;
3052 int *coords, ncoords, coordsize;
3054 /* Ick: fake up `ds->tilesize' for macro expansion purposes */
3055 struct { int tilesize; } ads, *ds = &ads;
3056 /* We can't call game_set_size() here because we don't want a blitter */
3057 ads.tilesize = tilesize;
3059 ink = print_mono_colour(dr, 0);
3060 for (i = 0; i < FOUR; i++)
3061 c[i] = print_rgb_hatched_colour(dr, map_colours[i][0],
3062 map_colours[i][1], map_colours[i][2],
3068 print_line_width(dr, TILESIZE / 16);
3071 * Draw a single filled polygon around each region.
3073 for (r = 0; r < n; r++) {
3074 int octants[8], lastdir, d1, d2, ox, oy;
3077 * Start by finding a point on the region boundary. Any
3078 * point will do. To do this, we'll search for a square
3079 * containing the region and then decide which corner of it
3083 for (y = 0; y < h; y++) {
3084 for (x = 0; x < w; x++) {
3085 if (state->map->map[wh*0+y*w+x] == r ||
3086 state->map->map[wh*1+y*w+x] == r ||
3087 state->map->map[wh*2+y*w+x] == r ||
3088 state->map->map[wh*3+y*w+x] == r)
3094 assert(y < h && x < w); /* we must have found one somewhere */
3096 * This is the first square in lexicographic order which
3097 * contains part of this region. Therefore, one of the top
3098 * two corners of the square must be what we're after. The
3099 * only case in which it isn't the top left one is if the
3100 * square is diagonally divided and the region is in the
3101 * bottom right half.
3103 if (state->map->map[wh*TE+y*w+x] != r &&
3104 state->map->map[wh*LE+y*w+x] != r)
3105 x++; /* could just as well have done y++ */
3108 * Now we have a point on the region boundary. Trace around
3109 * the region until we come back to this point,
3110 * accumulating coordinates for a polygon draw operation as
3120 * There are eight possible directions we could head in
3121 * from here. We identify them by octant numbers, and
3122 * we also use octant numbers to identify the spaces
3135 octants[0] = x<w && y>0 ? state->map->map[wh*LE+(y-1)*w+x] : -1;
3136 octants[1] = x<w && y>0 ? state->map->map[wh*BE+(y-1)*w+x] : -1;
3137 octants[2] = x<w && y<h ? state->map->map[wh*TE+y*w+x] : -1;
3138 octants[3] = x<w && y<h ? state->map->map[wh*LE+y*w+x] : -1;
3139 octants[4] = x>0 && y<h ? state->map->map[wh*RE+y*w+(x-1)] : -1;
3140 octants[5] = x>0 && y<h ? state->map->map[wh*TE+y*w+(x-1)] : -1;
3141 octants[6] = x>0 && y>0 ? state->map->map[wh*BE+(y-1)*w+(x-1)] :-1;
3142 octants[7] = x>0 && y>0 ? state->map->map[wh*RE+(y-1)*w+(x-1)] :-1;
3145 for (i = 0; i < 8; i++)
3146 if ((octants[i] == r) ^ (octants[(i+1)%8] == r)) {
3154 assert(d1 != -1 && d2 != -1);
3159 * Now we're heading in direction d1. Save the current
3162 if (ncoords + 2 > coordsize) {
3164 coords = sresize(coords, coordsize, int);
3166 coords[ncoords++] = COORD(x);
3167 coords[ncoords++] = COORD(y);
3170 * Compute the new coordinates.
3172 x += (d1 % 4 == 3 ? 0 : d1 < 4 ? +1 : -1);
3173 y += (d1 % 4 == 1 ? 0 : d1 > 1 && d1 < 5 ? +1 : -1);
3174 assert(x >= 0 && x <= w && y >= 0 && y <= h);
3177 } while (x != ox || y != oy);
3179 draw_polygon(dr, coords, ncoords/2,
3180 state->colouring[r] >= 0 ?
3181 c[state->colouring[r]] : -1, ink);
3190 const struct game thegame = {
3191 "Map", "games.map", "map",
3198 TRUE, game_configure, custom_params,
3206 FALSE, game_can_format_as_text_now, game_text_format,
3214 20, game_compute_size, game_set_size,
3217 game_free_drawstate,
3221 TRUE, TRUE, game_print_size, game_print,
3222 FALSE, /* wants_statusbar */
3223 FALSE, game_timing_state,
3227 #ifdef STANDALONE_SOLVER
3229 int main(int argc, char **argv)
3233 char *id = NULL, *desc, *err;
3235 int ret, diff, really_verbose = FALSE;
3236 struct solver_scratch *sc;
3239 while (--argc > 0) {
3241 if (!strcmp(p, "-v")) {
3242 really_verbose = TRUE;
3243 } else if (!strcmp(p, "-g")) {
3245 } else if (*p == '-') {
3246 fprintf(stderr, "%s: unrecognised option `%s'\n", argv[0], p);
3254 fprintf(stderr, "usage: %s [-g | -v] <game_id>\n", argv[0]);
3258 desc = strchr(id, ':');
3260 fprintf(stderr, "%s: game id expects a colon in it\n", argv[0]);
3265 p = default_params();
3266 decode_params(p, id);
3267 err = validate_desc(p, desc);
3269 fprintf(stderr, "%s: %s\n", argv[0], err);
3272 s = new_game(NULL, p, desc);
3274 sc = new_scratch(s->map->graph, s->map->n, s->map->ngraph);
3277 * When solving an Easy puzzle, we don't want to bother the
3278 * user with Hard-level deductions. For this reason, we grade
3279 * the puzzle internally before doing anything else.
3281 ret = -1; /* placate optimiser */
3282 for (diff = 0; diff < DIFFCOUNT; diff++) {
3283 for (i = 0; i < s->map->n; i++)
3284 if (!s->map->immutable[i])
3285 s->colouring[i] = -1;
3286 ret = map_solver(sc, s->map->graph, s->map->n, s->map->ngraph,
3287 s->colouring, diff);
3292 if (diff == DIFFCOUNT) {
3294 printf("Difficulty rating: harder than Hard, or ambiguous\n");
3296 printf("Unable to find a unique solution\n");
3300 printf("Difficulty rating: impossible (no solution exists)\n");
3302 printf("Difficulty rating: %s\n", map_diffnames[diff]);
3304 verbose = really_verbose;
3305 for (i = 0; i < s->map->n; i++)
3306 if (!s->map->immutable[i])
3307 s->colouring[i] = -1;
3308 ret = map_solver(sc, s->map->graph, s->map->n, s->map->ngraph,
3309 s->colouring, diff);
3311 printf("Puzzle is inconsistent\n");
3315 for (i = 0; i < s->map->n; i++) {
3316 printf("%5d <- %c%c", i, colnames[s->colouring[i]],
3317 (col < 6 && i+1 < s->map->n ? ' ' : '\n'));
3330 /* vim: set shiftwidth=4 tabstop=8: */