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1 | /* |
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2 | * loopy.c: |
3 | * |
4 | * An implementation of the Nikoli game 'Loop the loop'. |
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5 | * (c) Mike Pinna, 2005, 2006 |
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6 | * Substantially rewritten to allowing for more general types of grid. |
7 | * (c) Lambros Lambrou 2008 |
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8 | * |
9 | * vim: set shiftwidth=4 :set textwidth=80: |
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10 | */ |
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11 | |
12 | /* |
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13 | * Possible future solver enhancements: |
14 | * |
15 | * - There's an interesting deductive technique which makes use |
16 | * of topology rather than just graph theory. Each _face_ in |
17 | * the grid is either inside or outside the loop; you can tell |
18 | * that two faces are on the same side of the loop if they're |
19 | * separated by a LINE_NO (or, more generally, by a path |
20 | * crossing no LINE_UNKNOWNs and an even number of LINE_YESes), |
21 | * and on the opposite side of the loop if they're separated by |
22 | * a LINE_YES (or an odd number of LINE_YESes and no |
23 | * LINE_UNKNOWNs). Oh, and any face separated from the outside |
24 | * of the grid by a LINE_YES or a LINE_NO is on the inside or |
25 | * outside respectively. So if you can track this for all |
26 | * faces, you figure out the state of the line between a pair |
27 | * once their relative insideness is known. |
28 | * + The way I envisage this working is simply to keep an edsf |
29 | * of all _faces_, which indicates whether they're on |
30 | * opposite sides of the loop from one another. We also |
31 | * include a special entry in the edsf for the infinite |
32 | * exterior "face". |
33 | * + So, the simple way to do this is to just go through the |
34 | * edges: every time we see an edge in a state other than |
35 | * LINE_UNKNOWN which separates two faces that aren't in the |
36 | * same edsf class, we can rectify that by merging the |
37 | * classes. Then, conversely, an edge in LINE_UNKNOWN state |
38 | * which separates two faces that _are_ in the same edsf |
39 | * class can immediately have its state determined. |
40 | * + But you can go one better, if you're prepared to loop |
41 | * over all _pairs_ of edges. Suppose we have edges A and B, |
42 | * which respectively separate faces A1,A2 and B1,B2. |
43 | * Suppose that A,B are in the same edge-edsf class and that |
44 | * A1,B1 (wlog) are in the same face-edsf class; then we can |
45 | * immediately place A2,B2 into the same face-edsf class (as |
46 | * each other, not as A1 and A2) one way round or the other. |
47 | * And conversely again, if A1,B1 are in the same face-edsf |
48 | * class and so are A2,B2, then we can put A,B into the same |
49 | * face-edsf class. |
50 | * * Of course, this deduction requires a quadratic-time |
51 | * loop over all pairs of edges in the grid, so it should |
52 | * be reserved until there's nothing easier left to be |
53 | * done. |
54 | * |
55 | * - The generalised grid support has made me (SGT) notice a |
56 | * possible extension to the loop-avoidance code. When you have |
57 | * a path of connected edges such that no other edges at all |
58 | * are incident on any vertex in the middle of the path - or, |
59 | * alternatively, such that any such edges are already known to |
60 | * be LINE_NO - then you know those edges are either all |
61 | * LINE_YES or all LINE_NO. Hence you can mentally merge the |
62 | * entire path into a single long curly edge for the purposes |
63 | * of loop avoidance, and look directly at whether or not the |
64 | * extreme endpoints of the path are connected by some other |
65 | * route. I find this coming up fairly often when I play on the |
66 | * octagonal grid setting, so it might be worth implementing in |
67 | * the solver. |
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68 | * |
69 | * - (Just a speed optimisation.) Consider some todo list queue where every |
70 | * time we modify something we mark it for consideration by other bits of |
71 | * the solver, to save iteration over things that have already been done. |
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72 | */ |
73 | |
74 | #include <stdio.h> |
75 | #include <stdlib.h> |
7126ca41 |
76 | #include <stddef.h> |
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77 | #include <string.h> |
78 | #include <assert.h> |
79 | #include <ctype.h> |
80 | #include <math.h> |
81 | |
82 | #include "puzzles.h" |
83 | #include "tree234.h" |
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84 | #include "grid.h" |
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85 | |
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86 | /* Debugging options */ |
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87 | |
88 | /* |
89 | #define DEBUG_CACHES |
90 | #define SHOW_WORKING |
91 | #define DEBUG_DLINES |
92 | */ |
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93 | |
94 | /* ---------------------------------------------------------------------- |
95 | * Struct, enum and function declarations |
96 | */ |
97 | |
98 | enum { |
99 | COL_BACKGROUND, |
100 | COL_FOREGROUND, |
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101 | COL_LINEUNKNOWN, |
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102 | COL_HIGHLIGHT, |
103 | COL_MISTAKE, |
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104 | COL_SATISFIED, |
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105 | COL_FAINT, |
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106 | NCOLOURS |
107 | }; |
108 | |
109 | struct game_state { |
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110 | grid *game_grid; /* ref-counted (internally) */ |
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111 | |
112 | /* Put -1 in a face that doesn't get a clue */ |
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113 | signed char *clues; |
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114 | |
115 | /* Array of line states, to store whether each line is |
116 | * YES, NO or UNKNOWN */ |
117 | char *lines; |
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118 | |
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119 | unsigned char *line_errors; |
120 | |
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121 | int solved; |
122 | int cheated; |
123 | |
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124 | /* Used in game_text_format(), so that it knows what type of |
125 | * grid it's trying to render as ASCII text. */ |
126 | int grid_type; |
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127 | }; |
128 | |
129 | enum solver_status { |
130 | SOLVER_SOLVED, /* This is the only solution the solver could find */ |
131 | SOLVER_MISTAKE, /* This is definitely not a solution */ |
132 | SOLVER_AMBIGUOUS, /* This _might_ be an ambiguous solution */ |
133 | SOLVER_INCOMPLETE /* This may be a partial solution */ |
134 | }; |
135 | |
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136 | /* ------ Solver state ------ */ |
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137 | typedef struct solver_state { |
138 | game_state *state; |
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139 | enum solver_status solver_status; |
140 | /* NB looplen is the number of dots that are joined together at a point, ie a |
141 | * looplen of 1 means there are no lines to a particular dot */ |
142 | int *looplen; |
143 | |
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144 | /* Difficulty level of solver. Used by solver functions that want to |
145 | * vary their behaviour depending on the requested difficulty level. */ |
146 | int diff; |
147 | |
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148 | /* caches */ |
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149 | char *dot_yes_count; |
150 | char *dot_no_count; |
151 | char *face_yes_count; |
152 | char *face_no_count; |
153 | char *dot_solved, *face_solved; |
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154 | int *dotdsf; |
155 | |
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156 | /* Information for Normal level deductions: |
157 | * For each dline, store a bitmask for whether we know: |
158 | * (bit 0) at least one is YES |
159 | * (bit 1) at most one is YES */ |
160 | char *dlines; |
161 | |
162 | /* Hard level information */ |
163 | int *linedsf; |
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164 | } solver_state; |
165 | |
166 | /* |
167 | * Difficulty levels. I do some macro ickery here to ensure that my |
168 | * enum and the various forms of my name list always match up. |
169 | */ |
170 | |
171 | #define DIFFLIST(A) \ |
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172 | A(EASY,Easy,e) \ |
173 | A(NORMAL,Normal,n) \ |
174 | A(TRICKY,Tricky,t) \ |
175 | A(HARD,Hard,h) |
176 | #define ENUM(upper,title,lower) DIFF_ ## upper, |
177 | #define TITLE(upper,title,lower) #title, |
178 | #define ENCODE(upper,title,lower) #lower |
179 | #define CONFIG(upper,title,lower) ":" #title |
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180 | enum { DIFFLIST(ENUM) DIFF_MAX }; |
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181 | static char const *const diffnames[] = { DIFFLIST(TITLE) }; |
182 | static char const diffchars[] = DIFFLIST(ENCODE); |
183 | #define DIFFCONFIG DIFFLIST(CONFIG) |
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184 | |
185 | /* |
186 | * Solver routines, sorted roughly in order of computational cost. |
187 | * The solver will run the faster deductions first, and slower deductions are |
188 | * only invoked when the faster deductions are unable to make progress. |
189 | * Each function is associated with a difficulty level, so that the generated |
190 | * puzzles are solvable by applying only the functions with the chosen |
191 | * difficulty level or lower. |
192 | */ |
193 | #define SOLVERLIST(A) \ |
194 | A(trivial_deductions, DIFF_EASY) \ |
195 | A(dline_deductions, DIFF_NORMAL) \ |
196 | A(linedsf_deductions, DIFF_HARD) \ |
197 | A(loop_deductions, DIFF_EASY) |
198 | #define SOLVER_FN_DECL(fn,diff) static int fn(solver_state *); |
199 | #define SOLVER_FN(fn,diff) &fn, |
200 | #define SOLVER_DIFF(fn,diff) diff, |
201 | SOLVERLIST(SOLVER_FN_DECL) |
202 | static int (*(solver_fns[]))(solver_state *) = { SOLVERLIST(SOLVER_FN) }; |
203 | static int const solver_diffs[] = { SOLVERLIST(SOLVER_DIFF) }; |
204 | const int NUM_SOLVERS = sizeof(solver_diffs)/sizeof(*solver_diffs); |
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205 | |
206 | struct game_params { |
207 | int w, h; |
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208 | int diff; |
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209 | int type; |
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210 | }; |
211 | |
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212 | /* line_drawstate is the same as line_state, but with the extra ERROR |
213 | * possibility. The drawing code copies line_state to line_drawstate, |
214 | * except in the case that the line is an error. */ |
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215 | enum line_state { LINE_YES, LINE_UNKNOWN, LINE_NO }; |
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216 | enum line_drawstate { DS_LINE_YES, DS_LINE_UNKNOWN, |
217 | DS_LINE_NO, DS_LINE_ERROR }; |
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218 | |
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219 | #define OPP(line_state) \ |
220 | (2 - line_state) |
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221 | |
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222 | |
223 | struct game_drawstate { |
224 | int started; |
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225 | int tilesize; |
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226 | int flashing; |
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227 | int *textx, *texty; |
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228 | char *lines; |
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229 | char *clue_error; |
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230 | char *clue_satisfied; |
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231 | }; |
232 | |
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233 | static char *validate_desc(game_params *params, char *desc); |
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234 | static int dot_order(const game_state* state, int i, char line_type); |
235 | static int face_order(const game_state* state, int i, char line_type); |
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236 | static solver_state *solve_game_rec(const solver_state *sstate); |
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237 | |
238 | #ifdef DEBUG_CACHES |
239 | static void check_caches(const solver_state* sstate); |
240 | #else |
241 | #define check_caches(s) |
242 | #endif |
243 | |
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244 | /* ------- List of grid generators ------- */ |
245 | #define GRIDLIST(A) \ |
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246 | A(Squares,GRID_SQUARE,3,3) \ |
247 | A(Triangular,GRID_TRIANGULAR,3,3) \ |
248 | A(Honeycomb,GRID_HONEYCOMB,3,3) \ |
249 | A(Snub-Square,GRID_SNUBSQUARE,3,3) \ |
250 | A(Cairo,GRID_CAIRO,3,4) \ |
251 | A(Great-Hexagonal,GRID_GREATHEXAGONAL,3,3) \ |
252 | A(Octagonal,GRID_OCTAGONAL,3,3) \ |
253 | A(Kites,GRID_KITE,3,3) \ |
254 | A(Floret,GRID_FLORET,1,2) \ |
255 | A(Dodecagonal,GRID_DODECAGONAL,2,2) \ |
256 | A(Great-Dodecagonal,GRID_GREATDODECAGONAL,2,2) \ |
257 | A(Penrose (kite/dart),GRID_PENROSE_P2,3,3) \ |
258 | A(Penrose (rhombs),GRID_PENROSE_P3,3,3) |
259 | |
260 | #define GRID_NAME(title,type,amin,omin) #title, |
261 | #define GRID_CONFIG(title,type,amin,omin) ":" #title |
262 | #define GRID_TYPE(title,type,amin,omin) type, |
263 | #define GRID_SIZES(title,type,amin,omin) \ |
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264 | {amin, omin, \ |
265 | "Width and height for this grid type must both be at least " #amin, \ |
266 | "At least one of width and height for this grid type must be at least " #omin,}, |
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267 | static char const *const gridnames[] = { GRIDLIST(GRID_NAME) }; |
268 | #define GRID_CONFIGS GRIDLIST(GRID_CONFIG) |
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269 | static grid_type grid_types[] = { GRIDLIST(GRID_TYPE) }; |
270 | #define NUM_GRID_TYPES (sizeof(grid_types) / sizeof(grid_types[0])) |
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271 | static const struct { |
272 | int amin, omin; |
273 | char *aerr, *oerr; |
274 | } grid_size_limits[] = { GRIDLIST(GRID_SIZES) }; |
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275 | |
276 | /* Generates a (dynamically allocated) new grid, according to the |
277 | * type and size requested in params. Does nothing if the grid is already |
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278 | * generated. */ |
279 | static grid *loopy_generate_grid(game_params *params, char *grid_desc) |
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280 | { |
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281 | return grid_new(grid_types[params->type], params->w, params->h, grid_desc); |
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282 | } |
283 | |
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284 | /* ---------------------------------------------------------------------- |
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285 | * Preprocessor magic |
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286 | */ |
287 | |
288 | /* General constants */ |
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289 | #define PREFERRED_TILE_SIZE 32 |
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290 | #define BORDER(tilesize) ((tilesize) / 2) |
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291 | #define FLASH_TIME 0.5F |
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292 | |
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293 | #define BIT_SET(field, bit) ((field) & (1<<(bit))) |
294 | |
295 | #define SET_BIT(field, bit) (BIT_SET(field, bit) ? FALSE : \ |
296 | ((field) |= (1<<(bit)), TRUE)) |
297 | |
298 | #define CLEAR_BIT(field, bit) (BIT_SET(field, bit) ? \ |
299 | ((field) &= ~(1<<(bit)), TRUE) : FALSE) |
300 | |
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301 | #define CLUE2CHAR(c) \ |
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302 | ((c < 0) ? ' ' : c < 10 ? c + '0' : c - 10 + 'A') |
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303 | |
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304 | /* ---------------------------------------------------------------------- |
305 | * General struct manipulation and other straightforward code |
306 | */ |
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307 | |
308 | static game_state *dup_game(game_state *state) |
309 | { |
310 | game_state *ret = snew(game_state); |
311 | |
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312 | ret->game_grid = state->game_grid; |
313 | ret->game_grid->refcount++; |
314 | |
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315 | ret->solved = state->solved; |
316 | ret->cheated = state->cheated; |
317 | |
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318 | ret->clues = snewn(state->game_grid->num_faces, signed char); |
319 | memcpy(ret->clues, state->clues, state->game_grid->num_faces); |
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320 | |
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321 | ret->lines = snewn(state->game_grid->num_edges, char); |
322 | memcpy(ret->lines, state->lines, state->game_grid->num_edges); |
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323 | |
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324 | ret->line_errors = snewn(state->game_grid->num_edges, unsigned char); |
325 | memcpy(ret->line_errors, state->line_errors, state->game_grid->num_edges); |
326 | |
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327 | ret->grid_type = state->grid_type; |
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328 | return ret; |
329 | } |
330 | |
331 | static void free_game(game_state *state) |
332 | { |
333 | if (state) { |
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334 | grid_free(state->game_grid); |
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335 | sfree(state->clues); |
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336 | sfree(state->lines); |
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337 | sfree(state->line_errors); |
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338 | sfree(state); |
339 | } |
340 | } |
341 | |
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342 | static solver_state *new_solver_state(game_state *state, int diff) { |
343 | int i; |
344 | int num_dots = state->game_grid->num_dots; |
345 | int num_faces = state->game_grid->num_faces; |
346 | int num_edges = state->game_grid->num_edges; |
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347 | solver_state *ret = snew(solver_state); |
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348 | |
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349 | ret->state = dup_game(state); |
350 | |
351 | ret->solver_status = SOLVER_INCOMPLETE; |
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352 | ret->diff = diff; |
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353 | |
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354 | ret->dotdsf = snew_dsf(num_dots); |
355 | ret->looplen = snewn(num_dots, int); |
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356 | |
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357 | for (i = 0; i < num_dots; i++) { |
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358 | ret->looplen[i] = 1; |
359 | } |
360 | |
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361 | ret->dot_solved = snewn(num_dots, char); |
362 | ret->face_solved = snewn(num_faces, char); |
363 | memset(ret->dot_solved, FALSE, num_dots); |
364 | memset(ret->face_solved, FALSE, num_faces); |
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365 | |
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366 | ret->dot_yes_count = snewn(num_dots, char); |
367 | memset(ret->dot_yes_count, 0, num_dots); |
368 | ret->dot_no_count = snewn(num_dots, char); |
369 | memset(ret->dot_no_count, 0, num_dots); |
370 | ret->face_yes_count = snewn(num_faces, char); |
371 | memset(ret->face_yes_count, 0, num_faces); |
372 | ret->face_no_count = snewn(num_faces, char); |
373 | memset(ret->face_no_count, 0, num_faces); |
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374 | |
375 | if (diff < DIFF_NORMAL) { |
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376 | ret->dlines = NULL; |
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377 | } else { |
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378 | ret->dlines = snewn(2*num_edges, char); |
379 | memset(ret->dlines, 0, 2*num_edges); |
121aae4b |
380 | } |
381 | |
382 | if (diff < DIFF_HARD) { |
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383 | ret->linedsf = NULL; |
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384 | } else { |
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385 | ret->linedsf = snew_dsf(state->game_grid->num_edges); |
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386 | } |
387 | |
388 | return ret; |
389 | } |
390 | |
391 | static void free_solver_state(solver_state *sstate) { |
392 | if (sstate) { |
393 | free_game(sstate->state); |
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394 | sfree(sstate->dotdsf); |
395 | sfree(sstate->looplen); |
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396 | sfree(sstate->dot_solved); |
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397 | sfree(sstate->face_solved); |
398 | sfree(sstate->dot_yes_count); |
399 | sfree(sstate->dot_no_count); |
400 | sfree(sstate->face_yes_count); |
401 | sfree(sstate->face_no_count); |
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402 | |
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403 | /* OK, because sfree(NULL) is a no-op */ |
404 | sfree(sstate->dlines); |
405 | sfree(sstate->linedsf); |
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406 | |
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407 | sfree(sstate); |
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408 | } |
409 | } |
410 | |
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411 | static solver_state *dup_solver_state(const solver_state *sstate) { |
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412 | game_state *state = sstate->state; |
413 | int num_dots = state->game_grid->num_dots; |
414 | int num_faces = state->game_grid->num_faces; |
415 | int num_edges = state->game_grid->num_edges; |
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416 | solver_state *ret = snew(solver_state); |
417 | |
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418 | ret->state = state = dup_game(sstate->state); |
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419 | |
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420 | ret->solver_status = sstate->solver_status; |
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421 | ret->diff = sstate->diff; |
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422 | |
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423 | ret->dotdsf = snewn(num_dots, int); |
424 | ret->looplen = snewn(num_dots, int); |
425 | memcpy(ret->dotdsf, sstate->dotdsf, |
426 | num_dots * sizeof(int)); |
427 | memcpy(ret->looplen, sstate->looplen, |
428 | num_dots * sizeof(int)); |
429 | |
430 | ret->dot_solved = snewn(num_dots, char); |
431 | ret->face_solved = snewn(num_faces, char); |
432 | memcpy(ret->dot_solved, sstate->dot_solved, num_dots); |
433 | memcpy(ret->face_solved, sstate->face_solved, num_faces); |
434 | |
435 | ret->dot_yes_count = snewn(num_dots, char); |
436 | memcpy(ret->dot_yes_count, sstate->dot_yes_count, num_dots); |
437 | ret->dot_no_count = snewn(num_dots, char); |
438 | memcpy(ret->dot_no_count, sstate->dot_no_count, num_dots); |
439 | |
440 | ret->face_yes_count = snewn(num_faces, char); |
441 | memcpy(ret->face_yes_count, sstate->face_yes_count, num_faces); |
442 | ret->face_no_count = snewn(num_faces, char); |
443 | memcpy(ret->face_no_count, sstate->face_no_count, num_faces); |
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444 | |
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445 | if (sstate->dlines) { |
446 | ret->dlines = snewn(2*num_edges, char); |
447 | memcpy(ret->dlines, sstate->dlines, |
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448 | 2*num_edges); |
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449 | } else { |
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450 | ret->dlines = NULL; |
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451 | } |
452 | |
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453 | if (sstate->linedsf) { |
454 | ret->linedsf = snewn(num_edges, int); |
455 | memcpy(ret->linedsf, sstate->linedsf, |
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456 | num_edges * sizeof(int)); |
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457 | } else { |
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458 | ret->linedsf = NULL; |
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459 | } |
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460 | |
461 | return ret; |
462 | } |
463 | |
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464 | static game_params *default_params(void) |
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465 | { |
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466 | game_params *ret = snew(game_params); |
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467 | |
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468 | #ifdef SLOW_SYSTEM |
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469 | ret->h = 7; |
470 | ret->w = 7; |
121aae4b |
471 | #else |
472 | ret->h = 10; |
473 | ret->w = 10; |
474 | #endif |
475 | ret->diff = DIFF_EASY; |
7c95608a |
476 | ret->type = 0; |
477 | |
121aae4b |
478 | return ret; |
6193da8d |
479 | } |
480 | |
121aae4b |
481 | static game_params *dup_params(game_params *params) |
6193da8d |
482 | { |
121aae4b |
483 | game_params *ret = snew(game_params); |
7c95608a |
484 | |
121aae4b |
485 | *ret = *params; /* structure copy */ |
486 | return ret; |
487 | } |
6193da8d |
488 | |
121aae4b |
489 | static const game_params presets[] = { |
b1535c90 |
490 | #ifdef SMALL_SCREEN |
cebf0b0d |
491 | { 7, 7, DIFF_EASY, 0 }, |
492 | { 7, 7, DIFF_NORMAL, 0 }, |
493 | { 7, 7, DIFF_HARD, 0 }, |
494 | { 7, 7, DIFF_HARD, 1 }, |
495 | { 7, 7, DIFF_HARD, 2 }, |
496 | { 5, 5, DIFF_HARD, 3 }, |
497 | { 7, 7, DIFF_HARD, 4 }, |
498 | { 5, 4, DIFF_HARD, 5 }, |
499 | { 5, 5, DIFF_HARD, 6 }, |
500 | { 5, 5, DIFF_HARD, 7 }, |
501 | { 3, 3, DIFF_HARD, 8 }, |
502 | { 3, 3, DIFF_HARD, 9 }, |
503 | { 3, 3, DIFF_HARD, 10 }, |
504 | { 6, 6, DIFF_HARD, 11 }, |
505 | { 6, 6, DIFF_HARD, 12 }, |
b1535c90 |
506 | #else |
cebf0b0d |
507 | { 7, 7, DIFF_EASY, 0 }, |
508 | { 10, 10, DIFF_EASY, 0 }, |
509 | { 7, 7, DIFF_NORMAL, 0 }, |
510 | { 10, 10, DIFF_NORMAL, 0 }, |
511 | { 7, 7, DIFF_HARD, 0 }, |
512 | { 10, 10, DIFF_HARD, 0 }, |
513 | { 10, 10, DIFF_HARD, 1 }, |
514 | { 12, 10, DIFF_HARD, 2 }, |
515 | { 7, 7, DIFF_HARD, 3 }, |
516 | { 9, 9, DIFF_HARD, 4 }, |
517 | { 5, 4, DIFF_HARD, 5 }, |
518 | { 7, 7, DIFF_HARD, 6 }, |
519 | { 5, 5, DIFF_HARD, 7 }, |
520 | { 5, 5, DIFF_HARD, 8 }, |
521 | { 5, 4, DIFF_HARD, 9 }, |
522 | { 5, 4, DIFF_HARD, 10 }, |
523 | { 10, 10, DIFF_HARD, 11 }, |
524 | { 10, 10, DIFF_HARD, 12 } |
b1535c90 |
525 | #endif |
121aae4b |
526 | }; |
6193da8d |
527 | |
121aae4b |
528 | static int game_fetch_preset(int i, char **name, game_params **params) |
6193da8d |
529 | { |
1a739e2f |
530 | game_params *tmppar; |
121aae4b |
531 | char buf[80]; |
6193da8d |
532 | |
121aae4b |
533 | if (i < 0 || i >= lenof(presets)) |
534 | return FALSE; |
6193da8d |
535 | |
1a739e2f |
536 | tmppar = snew(game_params); |
537 | *tmppar = presets[i]; |
538 | *params = tmppar; |
7c95608a |
539 | sprintf(buf, "%dx%d %s - %s", tmppar->h, tmppar->w, |
540 | gridnames[tmppar->type], diffnames[tmppar->diff]); |
121aae4b |
541 | *name = dupstr(buf); |
542 | |
543 | return TRUE; |
6193da8d |
544 | } |
545 | |
546 | static void free_params(game_params *params) |
547 | { |
548 | sfree(params); |
549 | } |
550 | |
551 | static void decode_params(game_params *params, char const *string) |
552 | { |
553 | params->h = params->w = atoi(string); |
c0eb17ce |
554 | params->diff = DIFF_EASY; |
6193da8d |
555 | while (*string && isdigit((unsigned char)*string)) string++; |
556 | if (*string == 'x') { |
557 | string++; |
558 | params->h = atoi(string); |
121aae4b |
559 | while (*string && isdigit((unsigned char)*string)) string++; |
6193da8d |
560 | } |
7c95608a |
561 | if (*string == 't') { |
6193da8d |
562 | string++; |
7c95608a |
563 | params->type = atoi(string); |
121aae4b |
564 | while (*string && isdigit((unsigned char)*string)) string++; |
6193da8d |
565 | } |
c0eb17ce |
566 | if (*string == 'd') { |
567 | int i; |
c0eb17ce |
568 | string++; |
121aae4b |
569 | for (i = 0; i < DIFF_MAX; i++) |
570 | if (*string == diffchars[i]) |
571 | params->diff = i; |
572 | if (*string) string++; |
c0eb17ce |
573 | } |
6193da8d |
574 | } |
575 | |
576 | static char *encode_params(game_params *params, int full) |
577 | { |
578 | char str[80]; |
7c95608a |
579 | sprintf(str, "%dx%dt%d", params->w, params->h, params->type); |
6193da8d |
580 | if (full) |
7c95608a |
581 | sprintf(str + strlen(str), "d%c", diffchars[params->diff]); |
6193da8d |
582 | return dupstr(str); |
583 | } |
584 | |
585 | static config_item *game_configure(game_params *params) |
586 | { |
587 | config_item *ret; |
588 | char buf[80]; |
589 | |
7c95608a |
590 | ret = snewn(5, config_item); |
6193da8d |
591 | |
592 | ret[0].name = "Width"; |
593 | ret[0].type = C_STRING; |
594 | sprintf(buf, "%d", params->w); |
595 | ret[0].sval = dupstr(buf); |
596 | ret[0].ival = 0; |
597 | |
598 | ret[1].name = "Height"; |
599 | ret[1].type = C_STRING; |
600 | sprintf(buf, "%d", params->h); |
601 | ret[1].sval = dupstr(buf); |
602 | ret[1].ival = 0; |
603 | |
7c95608a |
604 | ret[2].name = "Grid type"; |
c0eb17ce |
605 | ret[2].type = C_CHOICES; |
7c95608a |
606 | ret[2].sval = GRID_CONFIGS; |
607 | ret[2].ival = params->type; |
6193da8d |
608 | |
7c95608a |
609 | ret[3].name = "Difficulty"; |
610 | ret[3].type = C_CHOICES; |
611 | ret[3].sval = DIFFCONFIG; |
612 | ret[3].ival = params->diff; |
613 | |
614 | ret[4].name = NULL; |
615 | ret[4].type = C_END; |
616 | ret[4].sval = NULL; |
617 | ret[4].ival = 0; |
6193da8d |
618 | |
619 | return ret; |
620 | } |
621 | |
622 | static game_params *custom_params(config_item *cfg) |
623 | { |
624 | game_params *ret = snew(game_params); |
625 | |
626 | ret->w = atoi(cfg[0].sval); |
627 | ret->h = atoi(cfg[1].sval); |
7c95608a |
628 | ret->type = cfg[2].ival; |
629 | ret->diff = cfg[3].ival; |
6193da8d |
630 | |
631 | return ret; |
632 | } |
633 | |
634 | static char *validate_params(game_params *params, int full) |
635 | { |
7c95608a |
636 | if (params->type < 0 || params->type >= NUM_GRID_TYPES) |
637 | return "Illegal grid type"; |
e3c9e042 |
638 | if (params->w < grid_size_limits[params->type].amin || |
639 | params->h < grid_size_limits[params->type].amin) |
640 | return grid_size_limits[params->type].aerr; |
641 | if (params->w < grid_size_limits[params->type].omin && |
642 | params->h < grid_size_limits[params->type].omin) |
643 | return grid_size_limits[params->type].oerr; |
c0eb17ce |
644 | |
645 | /* |
646 | * This shouldn't be able to happen at all, since decode_params |
647 | * and custom_params will never generate anything that isn't |
648 | * within range. |
649 | */ |
1a739e2f |
650 | assert(params->diff < DIFF_MAX); |
c0eb17ce |
651 | |
6193da8d |
652 | return NULL; |
653 | } |
654 | |
121aae4b |
655 | /* Returns a newly allocated string describing the current puzzle */ |
656 | static char *state_to_text(const game_state *state) |
6193da8d |
657 | { |
7c95608a |
658 | grid *g = state->game_grid; |
121aae4b |
659 | char *retval; |
7c95608a |
660 | int num_faces = g->num_faces; |
661 | char *description = snewn(num_faces + 1, char); |
121aae4b |
662 | char *dp = description; |
663 | int empty_count = 0; |
7c95608a |
664 | int i; |
6193da8d |
665 | |
7c95608a |
666 | for (i = 0; i < num_faces; i++) { |
667 | if (state->clues[i] < 0) { |
121aae4b |
668 | if (empty_count > 25) { |
669 | dp += sprintf(dp, "%c", (int)(empty_count + 'a' - 1)); |
670 | empty_count = 0; |
671 | } |
672 | empty_count++; |
673 | } else { |
674 | if (empty_count) { |
675 | dp += sprintf(dp, "%c", (int)(empty_count + 'a' - 1)); |
676 | empty_count = 0; |
677 | } |
7c95608a |
678 | dp += sprintf(dp, "%c", (int)CLUE2CHAR(state->clues[i])); |
121aae4b |
679 | } |
680 | } |
6193da8d |
681 | |
121aae4b |
682 | if (empty_count) |
1a739e2f |
683 | dp += sprintf(dp, "%c", (int)(empty_count + 'a' - 1)); |
121aae4b |
684 | |
685 | retval = dupstr(description); |
686 | sfree(description); |
687 | |
688 | return retval; |
6193da8d |
689 | } |
690 | |
cebf0b0d |
691 | #define GRID_DESC_SEP '_' |
692 | |
693 | /* Splits up a (optional) grid_desc from the game desc. Returns the |
694 | * grid_desc (which needs freeing) and updates the desc pointer to |
695 | * start of real desc, or returns NULL if no desc. */ |
696 | static char *extract_grid_desc(char **desc) |
697 | { |
698 | char *sep = strchr(*desc, GRID_DESC_SEP), *gd; |
699 | int gd_len; |
700 | |
701 | if (!sep) return NULL; |
702 | |
703 | gd_len = sep - (*desc); |
704 | gd = snewn(gd_len+1, char); |
705 | memcpy(gd, *desc, gd_len); |
706 | gd[gd_len] = '\0'; |
707 | |
708 | *desc = sep+1; |
709 | |
710 | return gd; |
711 | } |
712 | |
121aae4b |
713 | /* We require that the params pass the test in validate_params and that the |
714 | * description fills the entire game area */ |
715 | static char *validate_desc(game_params *params, char *desc) |
6193da8d |
716 | { |
121aae4b |
717 | int count = 0; |
7c95608a |
718 | grid *g; |
cebf0b0d |
719 | char *grid_desc, *ret; |
720 | |
721 | /* It's pretty inefficient to do this just for validation. All we need to |
722 | * know is the precise number of faces. */ |
723 | grid_desc = extract_grid_desc(&desc); |
724 | ret = grid_validate_desc(grid_types[params->type], params->w, params->h, grid_desc); |
725 | if (ret) return ret; |
726 | |
727 | g = loopy_generate_grid(params, grid_desc); |
728 | if (grid_desc) sfree(grid_desc); |
6193da8d |
729 | |
121aae4b |
730 | for (; *desc; ++desc) { |
918a098a |
731 | if ((*desc >= '0' && *desc <= '9') || (*desc >= 'A' && *desc <= 'Z')) { |
121aae4b |
732 | count++; |
733 | continue; |
734 | } |
735 | if (*desc >= 'a') { |
736 | count += *desc - 'a' + 1; |
737 | continue; |
738 | } |
739 | return "Unknown character in description"; |
6193da8d |
740 | } |
741 | |
7c95608a |
742 | if (count < g->num_faces) |
121aae4b |
743 | return "Description too short for board size"; |
7c95608a |
744 | if (count > g->num_faces) |
121aae4b |
745 | return "Description too long for board size"; |
6193da8d |
746 | |
cebf0b0d |
747 | grid_free(g); |
748 | |
121aae4b |
749 | return NULL; |
6193da8d |
750 | } |
751 | |
121aae4b |
752 | /* Sums the lengths of the numbers in range [0,n) */ |
753 | /* See equivalent function in solo.c for justification of this. */ |
754 | static int len_0_to_n(int n) |
6193da8d |
755 | { |
121aae4b |
756 | int len = 1; /* Counting 0 as a bit of a special case */ |
757 | int i; |
758 | |
759 | for (i = 1; i < n; i *= 10) { |
760 | len += max(n - i, 0); |
6193da8d |
761 | } |
121aae4b |
762 | |
763 | return len; |
6193da8d |
764 | } |
765 | |
121aae4b |
766 | static char *encode_solve_move(const game_state *state) |
767 | { |
7c95608a |
768 | int len; |
121aae4b |
769 | char *ret, *p; |
7c95608a |
770 | int i; |
771 | int num_edges = state->game_grid->num_edges; |
772 | |
121aae4b |
773 | /* This is going to return a string representing the moves needed to set |
774 | * every line in a grid to be the same as the ones in 'state'. The exact |
775 | * length of this string is predictable. */ |
6193da8d |
776 | |
121aae4b |
777 | len = 1; /* Count the 'S' prefix */ |
7c95608a |
778 | /* Numbers in all lines */ |
779 | len += len_0_to_n(num_edges); |
780 | /* For each line we also have a letter */ |
781 | len += num_edges; |
6193da8d |
782 | |
121aae4b |
783 | ret = snewn(len + 1, char); |
784 | p = ret; |
6193da8d |
785 | |
121aae4b |
786 | p += sprintf(p, "S"); |
6193da8d |
787 | |
7c95608a |
788 | for (i = 0; i < num_edges; i++) { |
789 | switch (state->lines[i]) { |
790 | case LINE_YES: |
791 | p += sprintf(p, "%dy", i); |
792 | break; |
793 | case LINE_NO: |
794 | p += sprintf(p, "%dn", i); |
795 | break; |
6193da8d |
796 | } |
6193da8d |
797 | } |
121aae4b |
798 | |
799 | /* No point in doing sums like that if they're going to be wrong */ |
800 | assert(strlen(ret) <= (size_t)len); |
801 | return ret; |
6193da8d |
802 | } |
803 | |
121aae4b |
804 | static game_ui *new_ui(game_state *state) |
6193da8d |
805 | { |
121aae4b |
806 | return NULL; |
807 | } |
6193da8d |
808 | |
121aae4b |
809 | static void free_ui(game_ui *ui) |
810 | { |
811 | } |
6193da8d |
812 | |
121aae4b |
813 | static char *encode_ui(game_ui *ui) |
814 | { |
815 | return NULL; |
816 | } |
6193da8d |
817 | |
121aae4b |
818 | static void decode_ui(game_ui *ui, char *encoding) |
819 | { |
820 | } |
6193da8d |
821 | |
121aae4b |
822 | static void game_changed_state(game_ui *ui, game_state *oldstate, |
823 | game_state *newstate) |
824 | { |
825 | } |
6193da8d |
826 | |
121aae4b |
827 | static void game_compute_size(game_params *params, int tilesize, |
828 | int *x, int *y) |
829 | { |
1515b973 |
830 | int grid_width, grid_height, rendered_width, rendered_height; |
cebf0b0d |
831 | int g_tilesize; |
832 | |
833 | grid_compute_size(grid_types[params->type], params->w, params->h, |
834 | &g_tilesize, &grid_width, &grid_height); |
1515b973 |
835 | |
7c95608a |
836 | /* multiply first to minimise rounding error on integer division */ |
cebf0b0d |
837 | rendered_width = grid_width * tilesize / g_tilesize; |
838 | rendered_height = grid_height * tilesize / g_tilesize; |
7c95608a |
839 | *x = rendered_width + 2 * BORDER(tilesize) + 1; |
840 | *y = rendered_height + 2 * BORDER(tilesize) + 1; |
121aae4b |
841 | } |
6193da8d |
842 | |
121aae4b |
843 | static void game_set_size(drawing *dr, game_drawstate *ds, |
7c95608a |
844 | game_params *params, int tilesize) |
121aae4b |
845 | { |
846 | ds->tilesize = tilesize; |
121aae4b |
847 | } |
6193da8d |
848 | |
121aae4b |
849 | static float *game_colours(frontend *fe, int *ncolours) |
850 | { |
851 | float *ret = snewn(4 * NCOLOURS, float); |
6193da8d |
852 | |
121aae4b |
853 | frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]); |
854 | |
855 | ret[COL_FOREGROUND * 3 + 0] = 0.0F; |
856 | ret[COL_FOREGROUND * 3 + 1] = 0.0F; |
857 | ret[COL_FOREGROUND * 3 + 2] = 0.0F; |
858 | |
32c231bb |
859 | /* |
860 | * We want COL_LINEUNKNOWN to be a yellow which is a bit darker |
861 | * than the background. (I previously set it to 0.8,0.8,0, but |
862 | * found that this went badly with the 0.8,0.8,0.8 favoured as a |
863 | * background by the Java frontend.) |
864 | */ |
865 | ret[COL_LINEUNKNOWN * 3 + 0] = ret[COL_BACKGROUND * 3 + 0] * 0.9F; |
866 | ret[COL_LINEUNKNOWN * 3 + 1] = ret[COL_BACKGROUND * 3 + 1] * 0.9F; |
7c95608a |
867 | ret[COL_LINEUNKNOWN * 3 + 2] = 0.0F; |
868 | |
121aae4b |
869 | ret[COL_HIGHLIGHT * 3 + 0] = 1.0F; |
870 | ret[COL_HIGHLIGHT * 3 + 1] = 1.0F; |
871 | ret[COL_HIGHLIGHT * 3 + 2] = 1.0F; |
872 | |
873 | ret[COL_MISTAKE * 3 + 0] = 1.0F; |
874 | ret[COL_MISTAKE * 3 + 1] = 0.0F; |
875 | ret[COL_MISTAKE * 3 + 2] = 0.0F; |
876 | |
7c95608a |
877 | ret[COL_SATISFIED * 3 + 0] = 0.0F; |
878 | ret[COL_SATISFIED * 3 + 1] = 0.0F; |
879 | ret[COL_SATISFIED * 3 + 2] = 0.0F; |
880 | |
ec909c7a |
881 | /* We want the faint lines to be a bit darker than the background. |
882 | * Except if the background is pretty dark already; then it ought to be a |
883 | * bit lighter. Oy vey. |
884 | */ |
885 | ret[COL_FAINT * 3 + 0] = ret[COL_BACKGROUND * 3 + 0] * 0.9F; |
886 | ret[COL_FAINT * 3 + 1] = ret[COL_BACKGROUND * 3 + 1] * 0.9F; |
887 | ret[COL_FAINT * 3 + 2] = ret[COL_BACKGROUND * 3 + 2] * 0.9F; |
888 | |
121aae4b |
889 | *ncolours = NCOLOURS; |
890 | return ret; |
891 | } |
892 | |
893 | static game_drawstate *game_new_drawstate(drawing *dr, game_state *state) |
894 | { |
895 | struct game_drawstate *ds = snew(struct game_drawstate); |
7c95608a |
896 | int num_faces = state->game_grid->num_faces; |
897 | int num_edges = state->game_grid->num_edges; |
e0936bbd |
898 | int i; |
121aae4b |
899 | |
7c95608a |
900 | ds->tilesize = 0; |
121aae4b |
901 | ds->started = 0; |
7c95608a |
902 | ds->lines = snewn(num_edges, char); |
903 | ds->clue_error = snewn(num_faces, char); |
904 | ds->clue_satisfied = snewn(num_faces, char); |
e0936bbd |
905 | ds->textx = snewn(num_faces, int); |
906 | ds->texty = snewn(num_faces, int); |
121aae4b |
907 | ds->flashing = 0; |
908 | |
7c95608a |
909 | memset(ds->lines, LINE_UNKNOWN, num_edges); |
910 | memset(ds->clue_error, 0, num_faces); |
911 | memset(ds->clue_satisfied, 0, num_faces); |
e0936bbd |
912 | for (i = 0; i < num_faces; i++) |
913 | ds->textx[i] = ds->texty[i] = -1; |
121aae4b |
914 | |
915 | return ds; |
916 | } |
917 | |
918 | static void game_free_drawstate(drawing *dr, game_drawstate *ds) |
919 | { |
a6bd4b9c |
920 | sfree(ds->textx); |
921 | sfree(ds->texty); |
121aae4b |
922 | sfree(ds->clue_error); |
7c95608a |
923 | sfree(ds->clue_satisfied); |
924 | sfree(ds->lines); |
121aae4b |
925 | sfree(ds); |
926 | } |
927 | |
928 | static int game_timing_state(game_state *state, game_ui *ui) |
929 | { |
930 | return TRUE; |
931 | } |
932 | |
933 | static float game_anim_length(game_state *oldstate, game_state *newstate, |
934 | int dir, game_ui *ui) |
935 | { |
936 | return 0.0F; |
937 | } |
938 | |
7c95608a |
939 | static int game_can_format_as_text_now(game_params *params) |
940 | { |
941 | if (params->type != 0) |
942 | return FALSE; |
943 | return TRUE; |
944 | } |
945 | |
121aae4b |
946 | static char *game_text_format(game_state *state) |
947 | { |
7c95608a |
948 | int w, h, W, H; |
949 | int x, y, i; |
950 | int cell_size; |
951 | char *ret; |
952 | grid *g = state->game_grid; |
953 | grid_face *f; |
954 | |
955 | assert(state->grid_type == 0); |
956 | |
957 | /* Work out the basic size unit */ |
958 | f = g->faces; /* first face */ |
959 | assert(f->order == 4); |
960 | /* The dots are ordered clockwise, so the two opposite |
961 | * corners are guaranteed to span the square */ |
962 | cell_size = abs(f->dots[0]->x - f->dots[2]->x); |
963 | |
964 | w = (g->highest_x - g->lowest_x) / cell_size; |
965 | h = (g->highest_y - g->lowest_y) / cell_size; |
966 | |
967 | /* Create a blank "canvas" to "draw" on */ |
968 | W = 2 * w + 2; |
969 | H = 2 * h + 1; |
970 | ret = snewn(W * H + 1, char); |
971 | for (y = 0; y < H; y++) { |
972 | for (x = 0; x < W-1; x++) { |
973 | ret[y*W + x] = ' '; |
121aae4b |
974 | } |
7c95608a |
975 | ret[y*W + W-1] = '\n'; |
976 | } |
977 | ret[H*W] = '\0'; |
978 | |
979 | /* Fill in edge info */ |
980 | for (i = 0; i < g->num_edges; i++) { |
981 | grid_edge *e = g->edges + i; |
982 | /* Cell coordinates, from (0,0) to (w-1,h-1) */ |
983 | int x1 = (e->dot1->x - g->lowest_x) / cell_size; |
984 | int x2 = (e->dot2->x - g->lowest_x) / cell_size; |
985 | int y1 = (e->dot1->y - g->lowest_y) / cell_size; |
986 | int y2 = (e->dot2->y - g->lowest_y) / cell_size; |
987 | /* Midpoint, in canvas coordinates (canvas coordinates are just twice |
988 | * cell coordinates) */ |
989 | x = x1 + x2; |
990 | y = y1 + y2; |
991 | switch (state->lines[i]) { |
992 | case LINE_YES: |
993 | ret[y*W + x] = (y1 == y2) ? '-' : '|'; |
994 | break; |
995 | case LINE_NO: |
996 | ret[y*W + x] = 'x'; |
997 | break; |
998 | case LINE_UNKNOWN: |
999 | break; /* already a space */ |
1000 | default: |
1001 | assert(!"Illegal line state"); |
121aae4b |
1002 | } |
121aae4b |
1003 | } |
7c95608a |
1004 | |
1005 | /* Fill in clues */ |
1006 | for (i = 0; i < g->num_faces; i++) { |
1515b973 |
1007 | int x1, x2, y1, y2; |
1008 | |
7c95608a |
1009 | f = g->faces + i; |
1010 | assert(f->order == 4); |
1011 | /* Cell coordinates, from (0,0) to (w-1,h-1) */ |
1515b973 |
1012 | x1 = (f->dots[0]->x - g->lowest_x) / cell_size; |
1013 | x2 = (f->dots[2]->x - g->lowest_x) / cell_size; |
1014 | y1 = (f->dots[0]->y - g->lowest_y) / cell_size; |
1015 | y2 = (f->dots[2]->y - g->lowest_y) / cell_size; |
7c95608a |
1016 | /* Midpoint, in canvas coordinates */ |
1017 | x = x1 + x2; |
1018 | y = y1 + y2; |
1019 | ret[y*W + x] = CLUE2CHAR(state->clues[i]); |
121aae4b |
1020 | } |
121aae4b |
1021 | return ret; |
1022 | } |
1023 | |
1024 | /* ---------------------------------------------------------------------- |
1025 | * Debug code |
1026 | */ |
1027 | |
1028 | #ifdef DEBUG_CACHES |
1029 | static void check_caches(const solver_state* sstate) |
1030 | { |
7c95608a |
1031 | int i; |
121aae4b |
1032 | const game_state *state = sstate->state; |
7c95608a |
1033 | const grid *g = state->game_grid; |
121aae4b |
1034 | |
7c95608a |
1035 | for (i = 0; i < g->num_dots; i++) { |
1036 | assert(dot_order(state, i, LINE_YES) == sstate->dot_yes_count[i]); |
1037 | assert(dot_order(state, i, LINE_NO) == sstate->dot_no_count[i]); |
121aae4b |
1038 | } |
1039 | |
7c95608a |
1040 | for (i = 0; i < g->num_faces; i++) { |
1041 | assert(face_order(state, i, LINE_YES) == sstate->face_yes_count[i]); |
1042 | assert(face_order(state, i, LINE_NO) == sstate->face_no_count[i]); |
121aae4b |
1043 | } |
1044 | } |
1045 | |
1046 | #if 0 |
1047 | #define check_caches(s) \ |
1048 | do { \ |
1049 | fprintf(stderr, "check_caches at line %d\n", __LINE__); \ |
1050 | check_caches(s); \ |
1051 | } while (0) |
1052 | #endif |
1053 | #endif /* DEBUG_CACHES */ |
1054 | |
1055 | /* ---------------------------------------------------------------------- |
1056 | * Solver utility functions |
1057 | */ |
1058 | |
7c95608a |
1059 | /* Sets the line (with index i) to the new state 'line_new', and updates |
1060 | * the cached counts of any affected faces and dots. |
1061 | * Returns TRUE if this actually changed the line's state. */ |
1062 | static int solver_set_line(solver_state *sstate, int i, |
1063 | enum line_state line_new |
121aae4b |
1064 | #ifdef SHOW_WORKING |
7c95608a |
1065 | , const char *reason |
121aae4b |
1066 | #endif |
7c95608a |
1067 | ) |
121aae4b |
1068 | { |
1069 | game_state *state = sstate->state; |
7c95608a |
1070 | grid *g; |
1071 | grid_edge *e; |
121aae4b |
1072 | |
1073 | assert(line_new != LINE_UNKNOWN); |
1074 | |
1075 | check_caches(sstate); |
1076 | |
7c95608a |
1077 | if (state->lines[i] == line_new) { |
1078 | return FALSE; /* nothing changed */ |
121aae4b |
1079 | } |
7c95608a |
1080 | state->lines[i] = line_new; |
121aae4b |
1081 | |
1082 | #ifdef SHOW_WORKING |
7c95608a |
1083 | fprintf(stderr, "solver: set line [%d] to %s (%s)\n", |
1084 | i, line_new == LINE_YES ? "YES" : "NO", |
121aae4b |
1085 | reason); |
1086 | #endif |
1087 | |
7c95608a |
1088 | g = state->game_grid; |
1089 | e = g->edges + i; |
1090 | |
1091 | /* Update the cache for both dots and both faces affected by this. */ |
121aae4b |
1092 | if (line_new == LINE_YES) { |
7c95608a |
1093 | sstate->dot_yes_count[e->dot1 - g->dots]++; |
1094 | sstate->dot_yes_count[e->dot2 - g->dots]++; |
1095 | if (e->face1) { |
1096 | sstate->face_yes_count[e->face1 - g->faces]++; |
1097 | } |
1098 | if (e->face2) { |
1099 | sstate->face_yes_count[e->face2 - g->faces]++; |
1100 | } |
121aae4b |
1101 | } else { |
7c95608a |
1102 | sstate->dot_no_count[e->dot1 - g->dots]++; |
1103 | sstate->dot_no_count[e->dot2 - g->dots]++; |
1104 | if (e->face1) { |
1105 | sstate->face_no_count[e->face1 - g->faces]++; |
1106 | } |
1107 | if (e->face2) { |
1108 | sstate->face_no_count[e->face2 - g->faces]++; |
1109 | } |
1110 | } |
1111 | |
121aae4b |
1112 | check_caches(sstate); |
7c95608a |
1113 | return TRUE; |
121aae4b |
1114 | } |
1115 | |
1116 | #ifdef SHOW_WORKING |
7c95608a |
1117 | #define solver_set_line(a, b, c) \ |
1118 | solver_set_line(a, b, c, __FUNCTION__) |
121aae4b |
1119 | #endif |
1120 | |
1121 | /* |
1122 | * Merge two dots due to the existence of an edge between them. |
1123 | * Updates the dsf tracking equivalence classes, and keeps track of |
1124 | * the length of path each dot is currently a part of. |
1125 | * Returns TRUE if the dots were already linked, ie if they are part of a |
1126 | * closed loop, and false otherwise. |
1127 | */ |
7c95608a |
1128 | static int merge_dots(solver_state *sstate, int edge_index) |
121aae4b |
1129 | { |
1130 | int i, j, len; |
7c95608a |
1131 | grid *g = sstate->state->game_grid; |
1132 | grid_edge *e = g->edges + edge_index; |
121aae4b |
1133 | |
7c95608a |
1134 | i = e->dot1 - g->dots; |
1135 | j = e->dot2 - g->dots; |
121aae4b |
1136 | |
1137 | i = dsf_canonify(sstate->dotdsf, i); |
1138 | j = dsf_canonify(sstate->dotdsf, j); |
1139 | |
1140 | if (i == j) { |
1141 | return TRUE; |
1142 | } else { |
1143 | len = sstate->looplen[i] + sstate->looplen[j]; |
1144 | dsf_merge(sstate->dotdsf, i, j); |
1145 | i = dsf_canonify(sstate->dotdsf, i); |
1146 | sstate->looplen[i] = len; |
1147 | return FALSE; |
1148 | } |
1149 | } |
1150 | |
121aae4b |
1151 | /* Merge two lines because the solver has deduced that they must be either |
1152 | * identical or opposite. Returns TRUE if this is new information, otherwise |
1153 | * FALSE. */ |
7c95608a |
1154 | static int merge_lines(solver_state *sstate, int i, int j, int inverse |
121aae4b |
1155 | #ifdef SHOW_WORKING |
1156 | , const char *reason |
1157 | #endif |
7c95608a |
1158 | ) |
121aae4b |
1159 | { |
7c95608a |
1160 | int inv_tmp; |
121aae4b |
1161 | |
7c95608a |
1162 | assert(i < sstate->state->game_grid->num_edges); |
1163 | assert(j < sstate->state->game_grid->num_edges); |
121aae4b |
1164 | |
315e47b9 |
1165 | i = edsf_canonify(sstate->linedsf, i, &inv_tmp); |
121aae4b |
1166 | inverse ^= inv_tmp; |
315e47b9 |
1167 | j = edsf_canonify(sstate->linedsf, j, &inv_tmp); |
121aae4b |
1168 | inverse ^= inv_tmp; |
1169 | |
315e47b9 |
1170 | edsf_merge(sstate->linedsf, i, j, inverse); |
121aae4b |
1171 | |
1172 | #ifdef SHOW_WORKING |
1173 | if (i != j) { |
7c95608a |
1174 | fprintf(stderr, "%s [%d] [%d] %s(%s)\n", |
1175 | __FUNCTION__, i, j, |
121aae4b |
1176 | inverse ? "inverse " : "", reason); |
1177 | } |
1178 | #endif |
1179 | return (i != j); |
1180 | } |
1181 | |
1182 | #ifdef SHOW_WORKING |
7c95608a |
1183 | #define merge_lines(a, b, c, d) \ |
1184 | merge_lines(a, b, c, d, __FUNCTION__) |
121aae4b |
1185 | #endif |
1186 | |
1187 | /* Count the number of lines of a particular type currently going into the |
7c95608a |
1188 | * given dot. */ |
1189 | static int dot_order(const game_state* state, int dot, char line_type) |
121aae4b |
1190 | { |
1191 | int n = 0; |
7c95608a |
1192 | grid *g = state->game_grid; |
1193 | grid_dot *d = g->dots + dot; |
1194 | int i; |
121aae4b |
1195 | |
7c95608a |
1196 | for (i = 0; i < d->order; i++) { |
1197 | grid_edge *e = d->edges[i]; |
1198 | if (state->lines[e - g->edges] == line_type) |
121aae4b |
1199 | ++n; |
1200 | } |
121aae4b |
1201 | return n; |
1202 | } |
1203 | |
1204 | /* Count the number of lines of a particular type currently surrounding the |
7c95608a |
1205 | * given face */ |
1206 | static int face_order(const game_state* state, int face, char line_type) |
121aae4b |
1207 | { |
1208 | int n = 0; |
7c95608a |
1209 | grid *g = state->game_grid; |
1210 | grid_face *f = g->faces + face; |
1211 | int i; |
121aae4b |
1212 | |
7c95608a |
1213 | for (i = 0; i < f->order; i++) { |
1214 | grid_edge *e = f->edges[i]; |
1215 | if (state->lines[e - g->edges] == line_type) |
1216 | ++n; |
1217 | } |
121aae4b |
1218 | return n; |
1219 | } |
1220 | |
7c95608a |
1221 | /* Set all lines bordering a dot of type old_type to type new_type |
121aae4b |
1222 | * Return value tells caller whether this function actually did anything */ |
7c95608a |
1223 | static int dot_setall(solver_state *sstate, int dot, |
1224 | char old_type, char new_type) |
121aae4b |
1225 | { |
1226 | int retval = FALSE, r; |
1227 | game_state *state = sstate->state; |
7c95608a |
1228 | grid *g; |
1229 | grid_dot *d; |
1230 | int i; |
1231 | |
121aae4b |
1232 | if (old_type == new_type) |
1233 | return FALSE; |
1234 | |
7c95608a |
1235 | g = state->game_grid; |
1236 | d = g->dots + dot; |
121aae4b |
1237 | |
7c95608a |
1238 | for (i = 0; i < d->order; i++) { |
1239 | int line_index = d->edges[i] - g->edges; |
1240 | if (state->lines[line_index] == old_type) { |
1241 | r = solver_set_line(sstate, line_index, new_type); |
1242 | assert(r == TRUE); |
1243 | retval = TRUE; |
1244 | } |
121aae4b |
1245 | } |
121aae4b |
1246 | return retval; |
1247 | } |
1248 | |
7c95608a |
1249 | /* Set all lines bordering a face of type old_type to type new_type */ |
1250 | static int face_setall(solver_state *sstate, int face, |
1251 | char old_type, char new_type) |
121aae4b |
1252 | { |
7c95608a |
1253 | int retval = FALSE, r; |
121aae4b |
1254 | game_state *state = sstate->state; |
7c95608a |
1255 | grid *g; |
1256 | grid_face *f; |
1257 | int i; |
121aae4b |
1258 | |
7c95608a |
1259 | if (old_type == new_type) |
1260 | return FALSE; |
1261 | |
1262 | g = state->game_grid; |
1263 | f = g->faces + face; |
121aae4b |
1264 | |
7c95608a |
1265 | for (i = 0; i < f->order; i++) { |
1266 | int line_index = f->edges[i] - g->edges; |
1267 | if (state->lines[line_index] == old_type) { |
1268 | r = solver_set_line(sstate, line_index, new_type); |
1269 | assert(r == TRUE); |
1270 | retval = TRUE; |
1271 | } |
1272 | } |
1273 | return retval; |
121aae4b |
1274 | } |
1275 | |
1276 | /* ---------------------------------------------------------------------- |
1277 | * Loop generation and clue removal |
1278 | */ |
1279 | |
7126ca41 |
1280 | /* We're going to store lists of current candidate faces for colouring black |
1281 | * or white. |
7c95608a |
1282 | * Each face gets a 'score', which tells us how adding that face right |
7126ca41 |
1283 | * now would affect the curliness of the solution loop. We're trying to |
7c95608a |
1284 | * maximise that quantity so will bias our random selection of faces to |
7126ca41 |
1285 | * colour those with high scores */ |
1286 | struct face_score { |
1287 | int white_score; |
1288 | int black_score; |
121aae4b |
1289 | unsigned long random; |
7126ca41 |
1290 | /* No need to store a grid_face* here. The 'face_scores' array will |
1291 | * be a list of 'face_score' objects, one for each face of the grid, so |
1292 | * the position (index) within the 'face_scores' array will determine |
1293 | * which face corresponds to a particular face_score. |
1294 | * Having a single 'face_scores' array for all faces simplifies memory |
1295 | * management, and probably improves performance, because we don't have to |
1296 | * malloc/free each individual face_score, and we don't have to maintain |
1297 | * a mapping from grid_face* pointers to face_score* pointers. |
1298 | */ |
121aae4b |
1299 | }; |
1300 | |
7126ca41 |
1301 | static int generic_sort_cmpfn(void *v1, void *v2, size_t offset) |
121aae4b |
1302 | { |
7126ca41 |
1303 | struct face_score *f1 = v1; |
1304 | struct face_score *f2 = v2; |
121aae4b |
1305 | int r; |
1306 | |
7126ca41 |
1307 | r = *(int *)((char *)f2 + offset) - *(int *)((char *)f1 + offset); |
121aae4b |
1308 | if (r) { |
1309 | return r; |
1310 | } |
1311 | |
7c95608a |
1312 | if (f1->random < f2->random) |
121aae4b |
1313 | return -1; |
7c95608a |
1314 | else if (f1->random > f2->random) |
121aae4b |
1315 | return 1; |
1316 | |
1317 | /* |
7c95608a |
1318 | * It's _just_ possible that two faces might have been given |
121aae4b |
1319 | * the same random value. In that situation, fall back to |
7126ca41 |
1320 | * comparing based on the positions within the face_scores list. |
7c95608a |
1321 | * This introduces a tiny directional bias, but not a significant one. |
121aae4b |
1322 | */ |
7126ca41 |
1323 | return f1 - f2; |
1324 | } |
1325 | |
1326 | static int white_sort_cmpfn(void *v1, void *v2) |
1327 | { |
1328 | return generic_sort_cmpfn(v1, v2, offsetof(struct face_score,white_score)); |
1329 | } |
1330 | |
1331 | static int black_sort_cmpfn(void *v1, void *v2) |
1332 | { |
1333 | return generic_sort_cmpfn(v1, v2, offsetof(struct face_score,black_score)); |
121aae4b |
1334 | } |
1335 | |
7126ca41 |
1336 | enum face_colour { FACE_WHITE, FACE_GREY, FACE_BLACK }; |
7c95608a |
1337 | |
1338 | /* face should be of type grid_face* here. */ |
7126ca41 |
1339 | #define FACE_COLOUR(face) \ |
1340 | ( (face) == NULL ? FACE_BLACK : \ |
7c95608a |
1341 | board[(face) - g->faces] ) |
1342 | |
1343 | /* 'board' is an array of these enums, indicating which faces are |
7126ca41 |
1344 | * currently black/white/grey. 'colour' is FACE_WHITE or FACE_BLACK. |
1345 | * Returns whether it's legal to colour the given face with this colour. */ |
1346 | static int can_colour_face(grid *g, char* board, int face_index, |
1347 | enum face_colour colour) |
7c95608a |
1348 | { |
1349 | int i, j; |
1350 | grid_face *test_face = g->faces + face_index; |
1351 | grid_face *starting_face, *current_face; |
24575af2 |
1352 | grid_dot *starting_dot; |
7c95608a |
1353 | int transitions; |
7126ca41 |
1354 | int current_state, s; /* booleans: equal or not-equal to 'colour' */ |
1355 | int found_same_coloured_neighbour = FALSE; |
1356 | assert(board[face_index] != colour); |
7c95608a |
1357 | |
7126ca41 |
1358 | /* Can only consider a face for colouring if it's adjacent to a face |
1359 | * with the same colour. */ |
7c95608a |
1360 | for (i = 0; i < test_face->order; i++) { |
1361 | grid_edge *e = test_face->edges[i]; |
1362 | grid_face *f = (e->face1 == test_face) ? e->face2 : e->face1; |
7126ca41 |
1363 | if (FACE_COLOUR(f) == colour) { |
1364 | found_same_coloured_neighbour = TRUE; |
7c95608a |
1365 | break; |
1366 | } |
1367 | } |
7126ca41 |
1368 | if (!found_same_coloured_neighbour) |
7c95608a |
1369 | return FALSE; |
1370 | |
7126ca41 |
1371 | /* Need to avoid creating a loop of faces of this colour around some |
1372 | * differently-coloured faces. |
1373 | * Also need to avoid meeting a same-coloured face at a corner, with |
1374 | * other-coloured faces in between. Here's a simple test that (I believe) |
1375 | * takes care of both these conditions: |
7c95608a |
1376 | * |
1377 | * Take the circular path formed by this face's edges, and inflate it |
1378 | * slightly outwards. Imagine walking around this path and consider |
1379 | * the faces that you visit in sequence. This will include all faces |
1380 | * touching the given face, either along an edge or just at a corner. |
7126ca41 |
1381 | * Count the number of 'colour'/not-'colour' transitions you encounter, as |
1382 | * you walk along the complete loop. This will obviously turn out to be |
1383 | * an even number. |
1384 | * If 0, we're either in the middle of an "island" of this colour (should |
1385 | * be impossible as we're not supposed to create black or white loops), |
1386 | * or we're about to start a new island - also not allowed. |
1387 | * If 4 or greater, there are too many separate coloured regions touching |
1388 | * this face, and colouring it would create a loop or a corner-violation. |
7c95608a |
1389 | * The only allowed case is when the count is exactly 2. */ |
1390 | |
1391 | /* i points to a dot around the test face. |
1392 | * j points to a face around the i^th dot. |
1393 | * The current face will always be: |
1394 | * test_face->dots[i]->faces[j] |
1395 | * We assume dots go clockwise around the test face, |
1396 | * and faces go clockwise around dots. */ |
24575af2 |
1397 | |
1398 | /* |
1399 | * The end condition is slightly fiddly. In sufficiently strange |
1400 | * degenerate grids, our test face may be adjacent to the same |
1401 | * other face multiple times (typically if it's the exterior |
1402 | * face). Consider this, in particular: |
1403 | * |
1404 | * +--+ |
1405 | * | | |
1406 | * +--+--+ |
1407 | * | | | |
1408 | * +--+--+ |
1409 | * |
1410 | * The bottom left face there is adjacent to the exterior face |
1411 | * twice, so we can't just terminate our iteration when we reach |
1412 | * the same _face_ we started at. Furthermore, we can't |
1413 | * condition on having the same (i,j) pair either, because |
1414 | * several (i,j) pairs identify the bottom left contiguity with |
1415 | * the exterior face! We canonicalise the (i,j) pair by taking |
1416 | * one step around before we set the termination tracking. |
1417 | */ |
1418 | |
7c95608a |
1419 | i = j = 0; |
24575af2 |
1420 | current_face = test_face->dots[0]->faces[0]; |
1421 | if (current_face == test_face) { |
7c95608a |
1422 | j = 1; |
24575af2 |
1423 | current_face = test_face->dots[0]->faces[1]; |
7c95608a |
1424 | } |
7c95608a |
1425 | transitions = 0; |
7126ca41 |
1426 | current_state = (FACE_COLOUR(current_face) == colour); |
24575af2 |
1427 | starting_dot = NULL; |
1428 | starting_face = NULL; |
1429 | while (TRUE) { |
7c95608a |
1430 | /* Advance to next face. |
1431 | * Need to loop here because it might take several goes to |
1432 | * find it. */ |
1433 | while (TRUE) { |
1434 | j++; |
1435 | if (j == test_face->dots[i]->order) |
1436 | j = 0; |
1437 | |
1438 | if (test_face->dots[i]->faces[j] == test_face) { |
1439 | /* Advance to next dot round test_face, then |
1440 | * find current_face around new dot |
1441 | * and advance to the next face clockwise */ |
1442 | i++; |
1443 | if (i == test_face->order) |
1444 | i = 0; |
1445 | for (j = 0; j < test_face->dots[i]->order; j++) { |
1446 | if (test_face->dots[i]->faces[j] == current_face) |
1447 | break; |
1448 | } |
1449 | /* Must actually find current_face around new dot, |
1450 | * or else something's wrong with the grid. */ |
1451 | assert(j != test_face->dots[i]->order); |
1452 | /* Found, so advance to next face and try again */ |
1453 | } else { |
1454 | break; |
1455 | } |
1456 | } |
1457 | /* (i,j) are now advanced to next face */ |
1458 | current_face = test_face->dots[i]->faces[j]; |
7126ca41 |
1459 | s = (FACE_COLOUR(current_face) == colour); |
24575af2 |
1460 | if (!starting_dot) { |
1461 | starting_dot = test_face->dots[i]; |
1462 | starting_face = current_face; |
1463 | current_state = s; |
1464 | } else { |
1465 | if (s != current_state) { |
1466 | ++transitions; |
1467 | current_state = s; |
1468 | if (transitions > 2) |
1469 | break; |
1470 | } |
1471 | if (test_face->dots[i] == starting_dot && |
1472 | current_face == starting_face) |
1473 | break; |
7c95608a |
1474 | } |
24575af2 |
1475 | } |
121aae4b |
1476 | |
7c95608a |
1477 | return (transitions == 2) ? TRUE : FALSE; |
1478 | } |
121aae4b |
1479 | |
7126ca41 |
1480 | /* Count the number of neighbours of 'face', having colour 'colour' */ |
1481 | static int face_num_neighbours(grid *g, char *board, grid_face *face, |
1482 | enum face_colour colour) |
7c95608a |
1483 | { |
7126ca41 |
1484 | int colour_count = 0; |
7c95608a |
1485 | int i; |
1486 | grid_face *f; |
1487 | grid_edge *e; |
1488 | for (i = 0; i < face->order; i++) { |
1489 | e = face->edges[i]; |
1490 | f = (e->face1 == face) ? e->face2 : e->face1; |
7126ca41 |
1491 | if (FACE_COLOUR(f) == colour) |
1492 | ++colour_count; |
7c95608a |
1493 | } |
7126ca41 |
1494 | return colour_count; |
7c95608a |
1495 | } |
121aae4b |
1496 | |
7126ca41 |
1497 | /* The 'score' of a face reflects its current desirability for selection |
1498 | * as the next face to colour white or black. We want to encourage moving |
1499 | * into grey areas and increasing loopiness, so we give scores according to |
1500 | * how many of the face's neighbours are currently coloured the same as the |
1501 | * proposed colour. */ |
1502 | static int face_score(grid *g, char *board, grid_face *face, |
1503 | enum face_colour colour) |
1504 | { |
1505 | /* Simple formula: score = 0 - num. same-coloured neighbours, |
1506 | * so a higher score means fewer same-coloured neighbours. */ |
1507 | return -face_num_neighbours(g, board, face, colour); |
1508 | } |
1509 | |
1510 | /* Generate a new complete set of clues for the given game_state. |
1511 | * The method is to generate a WHITE/BLACK colouring of all the faces, |
1512 | * such that the WHITE faces will define the inside of the path, and the |
1513 | * BLACK faces define the outside. |
1514 | * To do this, we initially colour all faces GREY. The infinite space outside |
1515 | * the grid is coloured BLACK, and we choose a random face to colour WHITE. |
1516 | * Then we gradually grow the BLACK and the WHITE regions, eliminating GREY |
1517 | * faces, until the grid is filled with BLACK/WHITE. As we grow the regions, |
1518 | * we avoid creating loops of a single colour, to preserve the topological |
1519 | * shape of the WHITE and BLACK regions. |
1520 | * We also try to make the boundary as loopy and twisty as possible, to avoid |
1521 | * generating paths that are uninteresting. |
1522 | * The algorithm works by choosing a BLACK/WHITE colour, then choosing a GREY |
1523 | * face that can be coloured with that colour (without violating the |
1524 | * topological shape of that region). It's not obvious, but I think this |
1525 | * algorithm is guaranteed to terminate without leaving any GREY faces behind. |
1526 | * Indeed, if there are any GREY faces at all, both the WHITE and BLACK |
1527 | * regions can be grown. |
1528 | * This is checked using assert()ions, and I haven't seen any failures yet. |
1529 | * |
1530 | * Hand-wavy proof: imagine what can go wrong... |
1531 | * |
1532 | * Could the white faces get completely cut off by the black faces, and still |
1533 | * leave some grey faces remaining? |
1534 | * No, because then the black faces would form a loop around both the white |
1535 | * faces and the grey faces, which is disallowed because we continually |
1536 | * maintain the correct topological shape of the black region. |
1537 | * Similarly, the black faces can never get cut off by the white faces. That |
1538 | * means both the WHITE and BLACK regions always have some room to grow into |
1539 | * the GREY regions. |
1540 | * Could it be that we can't colour some GREY face, because there are too many |
1541 | * WHITE/BLACK transitions as we walk round the face? (see the |
1542 | * can_colour_face() function for details) |
1543 | * No. Imagine otherwise, and we see WHITE/BLACK/WHITE/BLACK as we walk |
1544 | * around the face. The two WHITE faces would be connected by a WHITE path, |
1545 | * and the BLACK faces would be connected by a BLACK path. These paths would |
1546 | * have to cross, which is impossible. |
1547 | * Another thing that could go wrong: perhaps we can't find any GREY face to |
1548 | * colour WHITE, because it would create a loop-violation or a corner-violation |
1549 | * with the other WHITE faces? |
1550 | * This is a little bit tricky to prove impossible. Imagine you have such a |
1551 | * GREY face (that is, if you coloured it WHITE, you would create a WHITE loop |
1552 | * or corner violation). |
1553 | * That would cut all the non-white area into two blobs. One of those blobs |
1554 | * must be free of BLACK faces (because the BLACK stuff is a connected blob). |
1555 | * So we have a connected GREY area, completely surrounded by WHITE |
1556 | * (including the GREY face we've tentatively coloured WHITE). |
1557 | * A well-known result in graph theory says that you can always find a GREY |
1558 | * face whose removal leaves the remaining GREY area connected. And it says |
1559 | * there are at least two such faces, so we can always choose the one that |
1560 | * isn't the "tentative" GREY face. Colouring that face WHITE leaves |
1561 | * everything nice and connected, including that "tentative" GREY face which |
1562 | * acts as a gateway to the rest of the non-WHITE grid. |
1563 | */ |
121aae4b |
1564 | static void add_full_clues(game_state *state, random_state *rs) |
1565 | { |
7c95608a |
1566 | signed char *clues = state->clues; |
121aae4b |
1567 | char *board; |
7c95608a |
1568 | grid *g = state->game_grid; |
7126ca41 |
1569 | int i, j; |
7c95608a |
1570 | int num_faces = g->num_faces; |
7126ca41 |
1571 | struct face_score *face_scores; /* Array of face_score objects */ |
1572 | struct face_score *fs; /* Points somewhere in the above list */ |
1573 | struct grid_face *cur_face; |
1574 | tree234 *lightable_faces_sorted; |
1575 | tree234 *darkable_faces_sorted; |
1576 | int *face_list; |
1577 | int do_random_pass; |
7c95608a |
1578 | |
1579 | board = snewn(num_faces, char); |
121aae4b |
1580 | |
1581 | /* Make a board */ |
7126ca41 |
1582 | memset(board, FACE_GREY, num_faces); |
1583 | |
1584 | /* Create and initialise the list of face_scores */ |
1585 | face_scores = snewn(num_faces, struct face_score); |
1586 | for (i = 0; i < num_faces; i++) { |
1587 | face_scores[i].random = random_bits(rs, 31); |
8719c2e7 |
1588 | face_scores[i].black_score = face_scores[i].white_score = 0; |
7126ca41 |
1589 | } |
1590 | |
1591 | /* Colour a random, finite face white. The infinite face is implicitly |
1592 | * coloured black. Together, they will seed the random growth process |
1593 | * for the black and white areas. */ |
1594 | i = random_upto(rs, num_faces); |
1595 | board[i] = FACE_WHITE; |
7c95608a |
1596 | |
1597 | /* We need a way of favouring faces that will increase our loopiness. |
1598 | * We do this by maintaining a list of all candidate faces sorted by |
1599 | * their score and choose randomly from that with appropriate skew. |
1600 | * In order to avoid consistently biasing towards particular faces, we |
121aae4b |
1601 | * need the sort order _within_ each group of scores to be completely |
1602 | * random. But it would be abusing the hospitality of the tree234 data |
1603 | * structure if our comparison function were nondeterministic :-). So with |
7c95608a |
1604 | * each face we associate a random number that does not change during a |
121aae4b |
1605 | * particular run of the generator, and use that as a secondary sort key. |
7c95608a |
1606 | * Yes, this means we will be biased towards particular random faces in |
121aae4b |
1607 | * any one run but that doesn't actually matter. */ |
7c95608a |
1608 | |
7126ca41 |
1609 | lightable_faces_sorted = newtree234(white_sort_cmpfn); |
1610 | darkable_faces_sorted = newtree234(black_sort_cmpfn); |
121aae4b |
1611 | |
7126ca41 |
1612 | /* Initialise the lists of lightable and darkable faces. This is |
1613 | * slightly different from the code inside the while-loop, because we need |
1614 | * to check every face of the board (the grid structure does not keep a |
1615 | * list of the infinite face's neighbours). */ |
1616 | for (i = 0; i < num_faces; i++) { |
1617 | grid_face *f = g->faces + i; |
1618 | struct face_score *fs = face_scores + i; |
1619 | if (board[i] != FACE_GREY) continue; |
1620 | /* We need the full colourability check here, it's not enough simply |
1621 | * to check neighbourhood. On some grids, a neighbour of the infinite |
1622 | * face is not necessarily darkable. */ |
1623 | if (can_colour_face(g, board, i, FACE_BLACK)) { |
1624 | fs->black_score = face_score(g, board, f, FACE_BLACK); |
1625 | add234(darkable_faces_sorted, fs); |
1626 | } |
1627 | if (can_colour_face(g, board, i, FACE_WHITE)) { |
1628 | fs->white_score = face_score(g, board, f, FACE_WHITE); |
1629 | add234(lightable_faces_sorted, fs); |
1630 | } |
1631 | } |
7c95608a |
1632 | |
7126ca41 |
1633 | /* Colour faces one at a time until no more faces are colourable. */ |
121aae4b |
1634 | while (TRUE) |
1635 | { |
7126ca41 |
1636 | enum face_colour colour; |
1637 | struct face_score *fs_white, *fs_black; |
1638 | int c_lightable = count234(lightable_faces_sorted); |
1639 | int c_darkable = count234(darkable_faces_sorted); |
24575af2 |
1640 | if (c_lightable == 0 && c_darkable == 0) { |
1641 | /* No more faces we can use at all. */ |
7126ca41 |
1642 | break; |
1643 | } |
24575af2 |
1644 | assert(c_lightable != 0 && c_darkable != 0); |
121aae4b |
1645 | |
7126ca41 |
1646 | fs_white = (struct face_score *)index234(lightable_faces_sorted, 0); |
1647 | fs_black = (struct face_score *)index234(darkable_faces_sorted, 0); |
121aae4b |
1648 | |
7126ca41 |
1649 | /* Choose a colour, and colour the best available face |
1650 | * with that colour. */ |
1651 | colour = random_upto(rs, 2) ? FACE_WHITE : FACE_BLACK; |
121aae4b |
1652 | |
7126ca41 |
1653 | if (colour == FACE_WHITE) |
1654 | fs = fs_white; |
1655 | else |
1656 | fs = fs_black; |
1657 | assert(fs); |
1658 | i = fs - face_scores; |
1659 | assert(board[i] == FACE_GREY); |
1660 | board[i] = colour; |
1661 | |
1662 | /* Remove this newly-coloured face from the lists. These lists should |
1663 | * only contain grey faces. */ |
1664 | del234(lightable_faces_sorted, fs); |
1665 | del234(darkable_faces_sorted, fs); |
1666 | |
1667 | /* Remember which face we've just coloured */ |
1668 | cur_face = g->faces + i; |
1669 | |
1670 | /* The face we've just coloured potentially affects the colourability |
1671 | * and the scores of any neighbouring faces (touching at a corner or |
1672 | * edge). So the search needs to be conducted around all faces |
1673 | * touching the one we've just lit. Iterate over its corners, then |
1674 | * over each corner's faces. For each such face, we remove it from |
1675 | * the lists, recalculate any scores, then add it back to the lists |
1676 | * (depending on whether it is lightable, darkable or both). */ |
1677 | for (i = 0; i < cur_face->order; i++) { |
1678 | grid_dot *d = cur_face->dots[i]; |
7c95608a |
1679 | for (j = 0; j < d->order; j++) { |
7126ca41 |
1680 | grid_face *f = d->faces[j]; |
1681 | int fi; /* face index of f */ |
1682 | |
1683 | if (f == NULL) |
121aae4b |
1684 | continue; |
7126ca41 |
1685 | if (f == cur_face) |
7c95608a |
1686 | continue; |
7126ca41 |
1687 | |
1688 | /* If the face is already coloured, it won't be on our |
1689 | * lightable/darkable lists anyway, so we can skip it without |
1690 | * bothering with the removal step. */ |
1691 | if (FACE_COLOUR(f) != FACE_GREY) continue; |
1692 | |
1693 | /* Find the face index and face_score* corresponding to f */ |
1694 | fi = f - g->faces; |
1695 | fs = face_scores + fi; |
1696 | |
1697 | /* Remove from lightable list if it's in there. We do this, |
1698 | * even if it is still lightable, because the score might |
1699 | * be different, and we need to remove-then-add to maintain |
1700 | * correct sort order. */ |
1701 | del234(lightable_faces_sorted, fs); |
1702 | if (can_colour_face(g, board, fi, FACE_WHITE)) { |
1703 | fs->white_score = face_score(g, board, f, FACE_WHITE); |
1704 | add234(lightable_faces_sorted, fs); |
121aae4b |
1705 | } |
7126ca41 |
1706 | /* Do the same for darkable list. */ |
1707 | del234(darkable_faces_sorted, fs); |
1708 | if (can_colour_face(g, board, fi, FACE_BLACK)) { |
1709 | fs->black_score = face_score(g, board, f, FACE_BLACK); |
1710 | add234(darkable_faces_sorted, fs); |
121aae4b |
1711 | } |
1712 | } |
1713 | } |
121aae4b |
1714 | } |
1715 | |
1716 | /* Clean up */ |
7c95608a |
1717 | freetree234(lightable_faces_sorted); |
7126ca41 |
1718 | freetree234(darkable_faces_sorted); |
1719 | sfree(face_scores); |
1720 | |
1721 | /* The next step requires a shuffled list of all faces */ |
1722 | face_list = snewn(num_faces, int); |
1723 | for (i = 0; i < num_faces; ++i) { |
1724 | face_list[i] = i; |
1725 | } |
1726 | shuffle(face_list, num_faces, sizeof(int), rs); |
1727 | |
1728 | /* The above loop-generation algorithm can often leave large clumps |
1729 | * of faces of one colour. In extreme cases, the resulting path can be |
1730 | * degenerate and not very satisfying to solve. |
1731 | * This next step alleviates this problem: |
1732 | * Go through the shuffled list, and flip the colour of any face we can |
1733 | * legally flip, and which is adjacent to only one face of the opposite |
1734 | * colour - this tends to grow 'tendrils' into any clumps. |
1735 | * Repeat until we can find no more faces to flip. This will |
1736 | * eventually terminate, because each flip increases the loop's |
1737 | * perimeter, which cannot increase for ever. |
1738 | * The resulting path will have maximal loopiness (in the sense that it |
1739 | * cannot be improved "locally". Unfortunately, this allows a player to |
1740 | * make some illicit deductions. To combat this (and make the path more |
1741 | * interesting), we do one final pass making random flips. */ |
1742 | |
1743 | /* Set to TRUE for final pass */ |
1744 | do_random_pass = FALSE; |
1745 | |
1746 | while (TRUE) { |
1747 | /* Remember whether a flip occurred during this pass */ |
1748 | int flipped = FALSE; |
1749 | |
1750 | for (i = 0; i < num_faces; ++i) { |
1751 | int j = face_list[i]; |
1752 | enum face_colour opp = |
1753 | (board[j] == FACE_WHITE) ? FACE_BLACK : FACE_WHITE; |
1754 | if (can_colour_face(g, board, j, opp)) { |
1755 | grid_face *face = g->faces +j; |
1756 | if (do_random_pass) { |
1757 | /* final random pass */ |
1758 | if (!random_upto(rs, 10)) |
1759 | board[j] = opp; |
1760 | } else { |
1761 | /* normal pass - flip when neighbour count is 1 */ |
1762 | if (face_num_neighbours(g, board, face, opp) == 1) { |
1763 | board[j] = opp; |
1764 | flipped = TRUE; |
1765 | } |
1766 | } |
1767 | } |
1768 | } |
1769 | |
1770 | if (do_random_pass) break; |
1771 | if (!flipped) do_random_pass = TRUE; |
1772 | } |
1773 | |
1774 | sfree(face_list); |
7c95608a |
1775 | |
1776 | /* Fill out all the clues by initialising to 0, then iterating over |
1777 | * all edges and incrementing each clue as we find edges that border |
7126ca41 |
1778 | * between BLACK/WHITE faces. While we're at it, we verify that the |
1779 | * algorithm does work, and there aren't any GREY faces still there. */ |
7c95608a |
1780 | memset(clues, 0, num_faces); |
1781 | for (i = 0; i < g->num_edges; i++) { |
1782 | grid_edge *e = g->edges + i; |
1783 | grid_face *f1 = e->face1; |
1784 | grid_face *f2 = e->face2; |
7126ca41 |
1785 | enum face_colour c1 = FACE_COLOUR(f1); |
1786 | enum face_colour c2 = FACE_COLOUR(f2); |
1787 | assert(c1 != FACE_GREY); |
1788 | assert(c2 != FACE_GREY); |
1789 | if (c1 != c2) { |
7c95608a |
1790 | if (f1) clues[f1 - g->faces]++; |
1791 | if (f2) clues[f2 - g->faces]++; |
1792 | } |
121aae4b |
1793 | } |
1794 | |
1795 | sfree(board); |
1796 | } |
1797 | |
7c95608a |
1798 | |
1a739e2f |
1799 | static int game_has_unique_soln(const game_state *state, int diff) |
121aae4b |
1800 | { |
1801 | int ret; |
1802 | solver_state *sstate_new; |
1803 | solver_state *sstate = new_solver_state((game_state *)state, diff); |
7c95608a |
1804 | |
315e47b9 |
1805 | sstate_new = solve_game_rec(sstate); |
121aae4b |
1806 | |
1807 | assert(sstate_new->solver_status != SOLVER_MISTAKE); |
1808 | ret = (sstate_new->solver_status == SOLVER_SOLVED); |
1809 | |
1810 | free_solver_state(sstate_new); |
1811 | free_solver_state(sstate); |
1812 | |
1813 | return ret; |
1814 | } |
1815 | |
7c95608a |
1816 | |
121aae4b |
1817 | /* Remove clues one at a time at random. */ |
7c95608a |
1818 | static game_state *remove_clues(game_state *state, random_state *rs, |
1a739e2f |
1819 | int diff) |
121aae4b |
1820 | { |
7c95608a |
1821 | int *face_list; |
1822 | int num_faces = state->game_grid->num_faces; |
121aae4b |
1823 | game_state *ret = dup_game(state), *saved_ret; |
1824 | int n; |
121aae4b |
1825 | |
1826 | /* We need to remove some clues. We'll do this by forming a list of all |
1827 | * available clues, shuffling it, then going along one at a |
1828 | * time clearing each clue in turn for which doing so doesn't render the |
1829 | * board unsolvable. */ |
7c95608a |
1830 | face_list = snewn(num_faces, int); |
1831 | for (n = 0; n < num_faces; ++n) { |
1832 | face_list[n] = n; |
121aae4b |
1833 | } |
1834 | |
7c95608a |
1835 | shuffle(face_list, num_faces, sizeof(int), rs); |
121aae4b |
1836 | |
7c95608a |
1837 | for (n = 0; n < num_faces; ++n) { |
1838 | saved_ret = dup_game(ret); |
1839 | ret->clues[face_list[n]] = -1; |
121aae4b |
1840 | |
1841 | if (game_has_unique_soln(ret, diff)) { |
1842 | free_game(saved_ret); |
1843 | } else { |
1844 | free_game(ret); |
1845 | ret = saved_ret; |
1846 | } |
1847 | } |
7c95608a |
1848 | sfree(face_list); |
121aae4b |
1849 | |
1850 | return ret; |
1851 | } |
1852 | |
7c95608a |
1853 | |
121aae4b |
1854 | static char *new_game_desc(game_params *params, random_state *rs, |
1855 | char **aux, int interactive) |
1856 | { |
1857 | /* solution and description both use run-length encoding in obvious ways */ |
cebf0b0d |
1858 | char *retval, *game_desc, *grid_desc; |
7c95608a |
1859 | grid *g; |
1860 | game_state *state = snew(game_state); |
1861 | game_state *state_new; |
cebf0b0d |
1862 | |
1863 | grid_desc = grid_new_desc(grid_types[params->type], params->w, params->h, rs); |
1864 | state->game_grid = g = loopy_generate_grid(params, grid_desc); |
1865 | |
7c95608a |
1866 | state->clues = snewn(g->num_faces, signed char); |
1867 | state->lines = snewn(g->num_edges, char); |
b6bf0adc |
1868 | state->line_errors = snewn(g->num_edges, unsigned char); |
121aae4b |
1869 | |
7c95608a |
1870 | state->grid_type = params->type; |
121aae4b |
1871 | |
7c95608a |
1872 | newboard_please: |
121aae4b |
1873 | |
7c95608a |
1874 | memset(state->lines, LINE_UNKNOWN, g->num_edges); |
b6bf0adc |
1875 | memset(state->line_errors, 0, g->num_edges); |
121aae4b |
1876 | |
1877 | state->solved = state->cheated = FALSE; |
121aae4b |
1878 | |
1879 | /* Get a new random solvable board with all its clues filled in. Yes, this |
1880 | * can loop for ever if the params are suitably unfavourable, but |
1881 | * preventing games smaller than 4x4 seems to stop this happening */ |
121aae4b |
1882 | do { |
1883 | add_full_clues(state, rs); |
1884 | } while (!game_has_unique_soln(state, params->diff)); |
1885 | |
1886 | state_new = remove_clues(state, rs, params->diff); |
1887 | free_game(state); |
1888 | state = state_new; |
1889 | |
7c95608a |
1890 | |
121aae4b |
1891 | if (params->diff > 0 && game_has_unique_soln(state, params->diff-1)) { |
1a739e2f |
1892 | #ifdef SHOW_WORKING |
121aae4b |
1893 | fprintf(stderr, "Rejecting board, it is too easy\n"); |
1a739e2f |
1894 | #endif |
121aae4b |
1895 | goto newboard_please; |
1896 | } |
1897 | |
cebf0b0d |
1898 | game_desc = state_to_text(state); |
121aae4b |
1899 | |
1900 | free_game(state); |
7c95608a |
1901 | |
cebf0b0d |
1902 | if (grid_desc) { |
1903 | retval = snewn(strlen(grid_desc) + 1 + strlen(game_desc) + 1, char); |
1904 | sprintf(retval, "%s%c%s", grid_desc, GRID_DESC_SEP, game_desc); |
1905 | sfree(grid_desc); |
1906 | sfree(game_desc); |
1907 | } else { |
1908 | retval = game_desc; |
1909 | } |
1910 | |
121aae4b |
1911 | assert(!validate_desc(params, retval)); |
1912 | |
1913 | return retval; |
1914 | } |
1915 | |
1916 | static game_state *new_game(midend *me, game_params *params, char *desc) |
1917 | { |
7c95608a |
1918 | int i; |
121aae4b |
1919 | game_state *state = snew(game_state); |
1920 | int empties_to_make = 0; |
918a098a |
1921 | int n,n2; |
cebf0b0d |
1922 | const char *dp; |
1923 | char *grid_desc; |
7c95608a |
1924 | grid *g; |
1515b973 |
1925 | int num_faces, num_edges; |
1926 | |
cebf0b0d |
1927 | grid_desc = extract_grid_desc(&desc); |
1928 | state->game_grid = g = loopy_generate_grid(params, grid_desc); |
1929 | if (grid_desc) sfree(grid_desc); |
1930 | |
1931 | dp = desc; |
1932 | |
1515b973 |
1933 | num_faces = g->num_faces; |
1934 | num_edges = g->num_edges; |
121aae4b |
1935 | |
7c95608a |
1936 | state->clues = snewn(num_faces, signed char); |
1937 | state->lines = snewn(num_edges, char); |
b6bf0adc |
1938 | state->line_errors = snewn(num_edges, unsigned char); |
121aae4b |
1939 | |
1940 | state->solved = state->cheated = FALSE; |
1941 | |
7c95608a |
1942 | state->grid_type = params->type; |
1943 | |
1944 | for (i = 0; i < num_faces; i++) { |
121aae4b |
1945 | if (empties_to_make) { |
1946 | empties_to_make--; |
7c95608a |
1947 | state->clues[i] = -1; |
121aae4b |
1948 | continue; |
1949 | } |
1950 | |
1951 | assert(*dp); |
1952 | n = *dp - '0'; |
918a098a |
1953 | n2 = *dp - 'A' + 10; |
121aae4b |
1954 | if (n >= 0 && n < 10) { |
7c95608a |
1955 | state->clues[i] = n; |
918a098a |
1956 | } else if (n2 >= 10 && n2 < 36) { |
1957 | state->clues[i] = n2; |
121aae4b |
1958 | } else { |
1959 | n = *dp - 'a' + 1; |
1960 | assert(n > 0); |
7c95608a |
1961 | state->clues[i] = -1; |
121aae4b |
1962 | empties_to_make = n - 1; |
1963 | } |
1964 | ++dp; |
1965 | } |
1966 | |
7c95608a |
1967 | memset(state->lines, LINE_UNKNOWN, num_edges); |
b6bf0adc |
1968 | memset(state->line_errors, 0, num_edges); |
121aae4b |
1969 | return state; |
1970 | } |
1971 | |
b6bf0adc |
1972 | /* Calculates the line_errors data, and checks if the current state is a |
1973 | * solution */ |
1974 | static int check_completion(game_state *state) |
1975 | { |
1976 | grid *g = state->game_grid; |
1977 | int *dsf; |
1978 | int num_faces = g->num_faces; |
1979 | int i; |
1980 | int infinite_area, finite_area; |
1981 | int loops_found = 0; |
1982 | int found_edge_not_in_loop = FALSE; |
1983 | |
1984 | memset(state->line_errors, 0, g->num_edges); |
1985 | |
1986 | /* LL implementation of SGT's idea: |
1987 | * A loop will partition the grid into an inside and an outside. |
1988 | * If there is more than one loop, the grid will be partitioned into |
1989 | * even more distinct regions. We can therefore track equivalence of |
1990 | * faces, by saying that two faces are equivalent when there is a non-YES |
1991 | * edge between them. |
1992 | * We could keep track of the number of connected components, by counting |
1993 | * the number of dsf-merges that aren't no-ops. |
1994 | * But we're only interested in 3 separate cases: |
1995 | * no loops, one loop, more than one loop. |
1996 | * |
1997 | * No loops: all faces are equivalent to the infinite face. |
1998 | * One loop: only two equivalence classes - finite and infinite. |
1999 | * >= 2 loops: there are 2 distinct finite regions. |
2000 | * |
2001 | * So we simply make two passes through all the edges. |
2002 | * In the first pass, we dsf-merge the two faces bordering each non-YES |
2003 | * edge. |
2004 | * In the second pass, we look for YES-edges bordering: |
2005 | * a) two non-equivalent faces. |
2006 | * b) two non-equivalent faces, and one of them is part of a different |
2007 | * finite area from the first finite area we've seen. |
2008 | * |
2009 | * An occurrence of a) means there is at least one loop. |
2010 | * An occurrence of b) means there is more than one loop. |
2011 | * Edges satisfying a) are marked as errors. |
2012 | * |
2013 | * While we're at it, we set a flag if we find a YES edge that is not |
2014 | * part of a loop. |
2015 | * This information will help decide, if there's a single loop, whether it |
2016 | * is a candidate for being a solution (that is, all YES edges are part of |
2017 | * this loop). |
2018 | * |
2019 | * If there is a candidate loop, we then go through all clues and check |
2020 | * they are all satisfied. If so, we have found a solution and we can |
2021 | * unmark all line_errors. |
2022 | */ |
2023 | |
2024 | /* Infinite face is at the end - its index is num_faces. |
2025 | * This macro is just to make this obvious! */ |
2026 | #define INF_FACE num_faces |
2027 | dsf = snewn(num_faces + 1, int); |
2028 | dsf_init(dsf, num_faces + 1); |
2029 | |
2030 | /* First pass */ |
2031 | for (i = 0; i < g->num_edges; i++) { |
2032 | grid_edge *e = g->edges + i; |
2033 | int f1 = e->face1 ? e->face1 - g->faces : INF_FACE; |
2034 | int f2 = e->face2 ? e->face2 - g->faces : INF_FACE; |
2035 | if (state->lines[i] != LINE_YES) |
2036 | dsf_merge(dsf, f1, f2); |
2037 | } |
2038 | |
2039 | /* Second pass */ |
2040 | infinite_area = dsf_canonify(dsf, INF_FACE); |
2041 | finite_area = -1; |
2042 | for (i = 0; i < g->num_edges; i++) { |
2043 | grid_edge *e = g->edges + i; |
2044 | int f1 = e->face1 ? e->face1 - g->faces : INF_FACE; |
2045 | int can1 = dsf_canonify(dsf, f1); |
2046 | int f2 = e->face2 ? e->face2 - g->faces : INF_FACE; |
2047 | int can2 = dsf_canonify(dsf, f2); |
2048 | if (state->lines[i] != LINE_YES) continue; |
2049 | |
2050 | if (can1 == can2) { |
2051 | /* Faces are equivalent, so this edge not part of a loop */ |
2052 | found_edge_not_in_loop = TRUE; |
2053 | continue; |
2054 | } |
2055 | state->line_errors[i] = TRUE; |
2056 | if (loops_found == 0) loops_found = 1; |
2057 | |
2058 | /* Don't bother with further checks if we've already found 2 loops */ |
2059 | if (loops_found == 2) continue; |
2060 | |
2061 | if (finite_area == -1) { |
2062 | /* Found our first finite area */ |
2063 | if (can1 != infinite_area) |
2064 | finite_area = can1; |
2065 | else |
2066 | finite_area = can2; |
2067 | } |
2068 | |
2069 | /* Have we found a second area? */ |
2070 | if (finite_area != -1) { |
2071 | if (can1 != infinite_area && can1 != finite_area) { |
2072 | loops_found = 2; |
2073 | continue; |
2074 | } |
2075 | if (can2 != infinite_area && can2 != finite_area) { |
2076 | loops_found = 2; |
2077 | } |
2078 | } |
2079 | } |
2080 | |
2081 | /* |
2082 | printf("loops_found = %d\n", loops_found); |
2083 | printf("found_edge_not_in_loop = %s\n", |
2084 | found_edge_not_in_loop ? "TRUE" : "FALSE"); |
2085 | */ |
2086 | |
2087 | sfree(dsf); /* No longer need the dsf */ |
2088 | |
2089 | /* Have we found a candidate loop? */ |
2090 | if (loops_found == 1 && !found_edge_not_in_loop) { |
2091 | /* Yes, so check all clues are satisfied */ |
2092 | int found_clue_violation = FALSE; |
2093 | for (i = 0; i < num_faces; i++) { |
2094 | int c = state->clues[i]; |
2095 | if (c >= 0) { |
2096 | if (face_order(state, i, LINE_YES) != c) { |
2097 | found_clue_violation = TRUE; |
2098 | break; |
2099 | } |
2100 | } |
2101 | } |
2102 | |
2103 | if (!found_clue_violation) { |
2104 | /* The loop is good */ |
2105 | memset(state->line_errors, 0, g->num_edges); |
2106 | return TRUE; /* No need to bother checking for dot violations */ |
2107 | } |
2108 | } |
2109 | |
2110 | /* Check for dot violations */ |
2111 | for (i = 0; i < g->num_dots; i++) { |
2112 | int yes = dot_order(state, i, LINE_YES); |
2113 | int unknown = dot_order(state, i, LINE_UNKNOWN); |
2114 | if ((yes == 1 && unknown == 0) || (yes >= 3)) { |
2115 | /* violation, so mark all YES edges as errors */ |
2116 | grid_dot *d = g->dots + i; |
2117 | int j; |
2118 | for (j = 0; j < d->order; j++) { |
2119 | int e = d->edges[j] - g->edges; |
2120 | if (state->lines[e] == LINE_YES) |
2121 | state->line_errors[e] = TRUE; |
2122 | } |
2123 | } |
2124 | } |
2125 | return FALSE; |
2126 | } |
121aae4b |
2127 | |
2128 | /* ---------------------------------------------------------------------- |
2129 | * Solver logic |
2130 | * |
2131 | * Our solver modes operate as follows. Each mode also uses the modes above it. |
2132 | * |
2133 | * Easy Mode |
2134 | * Just implement the rules of the game. |
2135 | * |
315e47b9 |
2136 | * Normal and Tricky Modes |
7c95608a |
2137 | * For each (adjacent) pair of lines through each dot we store a bit for |
2138 | * whether at least one of them is on and whether at most one is on. (If we |
2139 | * know both or neither is on that's already stored more directly.) |
121aae4b |
2140 | * |
2141 | * Advanced Mode |
2142 | * Use edsf data structure to make equivalence classes of lines that are |
2143 | * known identical to or opposite to one another. |
2144 | */ |
2145 | |
121aae4b |
2146 | |
7c95608a |
2147 | /* DLines: |
2148 | * For general grids, we consider "dlines" to be pairs of lines joined |
2149 | * at a dot. The lines must be adjacent around the dot, so we can think of |
2150 | * a dline as being a dot+face combination. Or, a dot+edge combination where |
2151 | * the second edge is taken to be the next clockwise edge from the dot. |
2152 | * Original loopy code didn't have this extra restriction of the lines being |
2153 | * adjacent. From my tests with square grids, this extra restriction seems to |
2154 | * take little, if anything, away from the quality of the puzzles. |
2155 | * A dline can be uniquely identified by an edge/dot combination, given that |
2156 | * a dline-pair always goes clockwise around its common dot. The edge/dot |
2157 | * combination can be represented by an edge/bool combination - if bool is |
2158 | * TRUE, use edge->dot1 else use edge->dot2. So the total number of dlines is |
2159 | * exactly twice the number of edges in the grid - although the dlines |
2160 | * spanning the infinite face are not all that useful to the solver. |
2161 | * Note that, by convention, a dline goes clockwise around its common dot, |
2162 | * which means the dline goes anti-clockwise around its common face. |
2163 | */ |
121aae4b |
2164 | |
7c95608a |
2165 | /* Helper functions for obtaining an index into an array of dlines, given |
2166 | * various information. We assume the grid layout conventions about how |
2167 | * the various lists are interleaved - see grid_make_consistent() for |
2168 | * details. */ |
121aae4b |
2169 | |
7c95608a |
2170 | /* i points to the first edge of the dline pair, reading clockwise around |
2171 | * the dot. */ |
2172 | static int dline_index_from_dot(grid *g, grid_dot *d, int i) |
121aae4b |
2173 | { |
7c95608a |
2174 | grid_edge *e = d->edges[i]; |
121aae4b |
2175 | int ret; |
7c95608a |
2176 | #ifdef DEBUG_DLINES |
2177 | grid_edge *e2; |
2178 | int i2 = i+1; |
2179 | if (i2 == d->order) i2 = 0; |
2180 | e2 = d->edges[i2]; |
2181 | #endif |
2182 | ret = 2 * (e - g->edges) + ((e->dot1 == d) ? 1 : 0); |
2183 | #ifdef DEBUG_DLINES |
2184 | printf("dline_index_from_dot: d=%d,i=%d, edges [%d,%d] - %d\n", |
2185 | (int)(d - g->dots), i, (int)(e - g->edges), |
2186 | (int)(e2 - g->edges), ret); |
121aae4b |
2187 | #endif |
2188 | return ret; |
2189 | } |
7c95608a |
2190 | /* i points to the second edge of the dline pair, reading clockwise around |
2191 | * the face. That is, the edges of the dline, starting at edge{i}, read |
2192 | * anti-clockwise around the face. By layout conventions, the common dot |
2193 | * of the dline will be f->dots[i] */ |
2194 | static int dline_index_from_face(grid *g, grid_face *f, int i) |
121aae4b |
2195 | { |
7c95608a |
2196 | grid_edge *e = f->edges[i]; |
2197 | grid_dot *d = f->dots[i]; |
121aae4b |
2198 | int ret; |
7c95608a |
2199 | #ifdef DEBUG_DLINES |
2200 | grid_edge *e2; |
2201 | int i2 = i - 1; |
2202 | if (i2 < 0) i2 += f->order; |
2203 | e2 = f->edges[i2]; |
2204 | #endif |
2205 | ret = 2 * (e - g->edges) + ((e->dot1 == d) ? 1 : 0); |
2206 | #ifdef DEBUG_DLINES |
2207 | printf("dline_index_from_face: f=%d,i=%d, edges [%d,%d] - %d\n", |
2208 | (int)(f - g->faces), i, (int)(e - g->edges), |
2209 | (int)(e2 - g->edges), ret); |
121aae4b |
2210 | #endif |
2211 | return ret; |
2212 | } |
7c95608a |
2213 | static int is_atleastone(const char *dline_array, int index) |
121aae4b |
2214 | { |
7c95608a |
2215 | return BIT_SET(dline_array[index], 0); |
121aae4b |
2216 | } |
7c95608a |
2217 | static int set_atleastone(char *dline_array, int index) |
121aae4b |
2218 | { |
7c95608a |
2219 | return SET_BIT(dline_array[index], 0); |
121aae4b |
2220 | } |
7c95608a |
2221 | static int is_atmostone(const char *dline_array, int index) |
121aae4b |
2222 | { |
7c95608a |
2223 | return BIT_SET(dline_array[index], 1); |
2224 | } |
2225 | static int set_atmostone(char *dline_array, int index) |
2226 | { |
2227 | return SET_BIT(dline_array[index], 1); |
121aae4b |
2228 | } |
121aae4b |
2229 | |
2230 | static void array_setall(char *array, char from, char to, int len) |
2231 | { |
2232 | char *p = array, *p_old = p; |
2233 | int len_remaining = len; |
2234 | |
2235 | while ((p = memchr(p, from, len_remaining))) { |
2236 | *p = to; |
2237 | len_remaining -= p - p_old; |
2238 | p_old = p; |
2239 | } |
2240 | } |
6193da8d |
2241 | |
7c95608a |
2242 | /* Helper, called when doing dline dot deductions, in the case where we |
2243 | * have 4 UNKNOWNs, and two of them (adjacent) have *exactly* one YES between |
2244 | * them (because of dline atmostone/atleastone). |
2245 | * On entry, edge points to the first of these two UNKNOWNs. This function |
2246 | * will find the opposite UNKNOWNS (if they are adjacent to one another) |
2247 | * and set their corresponding dline to atleastone. (Setting atmostone |
2248 | * already happens in earlier dline deductions) */ |
2249 | static int dline_set_opp_atleastone(solver_state *sstate, |
2250 | grid_dot *d, int edge) |
121aae4b |
2251 | { |
7c95608a |
2252 | game_state *state = sstate->state; |
2253 | grid *g = state->game_grid; |
2254 | int N = d->order; |
2255 | int opp, opp2; |
2256 | for (opp = 0; opp < N; opp++) { |
2257 | int opp_dline_index; |
2258 | if (opp == edge || opp == edge+1 || opp == edge-1) |
2259 | continue; |
2260 | if (opp == 0 && edge == N-1) |
2261 | continue; |
2262 | if (opp == N-1 && edge == 0) |
2263 | continue; |
2264 | opp2 = opp + 1; |
2265 | if (opp2 == N) opp2 = 0; |
2266 | /* Check if opp, opp2 point to LINE_UNKNOWNs */ |
2267 | if (state->lines[d->edges[opp] - g->edges] != LINE_UNKNOWN) |
2268 | continue; |
2269 | if (state->lines[d->edges[opp2] - g->edges] != LINE_UNKNOWN) |
2270 | continue; |
2271 | /* Found opposite UNKNOWNS and they're next to each other */ |
2272 | opp_dline_index = dline_index_from_dot(g, d, opp); |
315e47b9 |
2273 | return set_atleastone(sstate->dlines, opp_dline_index); |
121aae4b |
2274 | } |
7c95608a |
2275 | return FALSE; |
121aae4b |
2276 | } |
6193da8d |
2277 | |
121aae4b |
2278 | |
7c95608a |
2279 | /* Set pairs of lines around this face which are known to be identical, to |
121aae4b |
2280 | * the given line_state */ |
7c95608a |
2281 | static int face_setall_identical(solver_state *sstate, int face_index, |
2282 | enum line_state line_new) |
121aae4b |
2283 | { |
2284 | /* can[dir] contains the canonical line associated with the line in |
2285 | * direction dir from the square in question. Similarly inv[dir] is |
2286 | * whether or not the line in question is inverse to its canonical |
2287 | * element. */ |
121aae4b |
2288 | int retval = FALSE; |
7c95608a |
2289 | game_state *state = sstate->state; |
2290 | grid *g = state->game_grid; |
2291 | grid_face *f = g->faces + face_index; |
2292 | int N = f->order; |
2293 | int i, j; |
2294 | int can1, can2, inv1, inv2; |
6193da8d |
2295 | |
7c95608a |
2296 | for (i = 0; i < N; i++) { |
2297 | int line1_index = f->edges[i] - g->edges; |
2298 | if (state->lines[line1_index] != LINE_UNKNOWN) |
2299 | continue; |
2300 | for (j = i + 1; j < N; j++) { |
2301 | int line2_index = f->edges[j] - g->edges; |
2302 | if (state->lines[line2_index] != LINE_UNKNOWN) |
121aae4b |
2303 | continue; |
6193da8d |
2304 | |
7c95608a |
2305 | /* Found two UNKNOWNS */ |
315e47b9 |
2306 | can1 = edsf_canonify(sstate->linedsf, line1_index, &inv1); |
2307 | can2 = edsf_canonify(sstate->linedsf, line2_index, &inv2); |
7c95608a |
2308 | if (can1 == can2 && inv1 == inv2) { |
2309 | solver_set_line(sstate, line1_index, line_new); |
2310 | solver_set_line(sstate, line2_index, line_new); |
6193da8d |
2311 | } |
2312 | } |
6193da8d |
2313 | } |
121aae4b |
2314 | return retval; |
2315 | } |
2316 | |
7c95608a |
2317 | /* Given a dot or face, and a count of LINE_UNKNOWNs, find them and |
2318 | * return the edge indices into e. */ |
2319 | static void find_unknowns(game_state *state, |
2320 | grid_edge **edge_list, /* Edge list to search (from a face or a dot) */ |
2321 | int expected_count, /* Number of UNKNOWNs (comes from solver's cache) */ |
2322 | int *e /* Returned edge indices */) |
2323 | { |
2324 | int c = 0; |
2325 | grid *g = state->game_grid; |
2326 | while (c < expected_count) { |
2327 | int line_index = *edge_list - g->edges; |
2328 | if (state->lines[line_index] == LINE_UNKNOWN) { |
2329 | e[c] = line_index; |
2330 | c++; |
6193da8d |
2331 | } |
7c95608a |
2332 | ++edge_list; |
6193da8d |
2333 | } |
6193da8d |
2334 | } |
2335 | |
7c95608a |
2336 | /* If we have a list of edges, and we know whether the number of YESs should |
2337 | * be odd or even, and there are only a few UNKNOWNs, we can do some simple |
2338 | * linedsf deductions. This can be used for both face and dot deductions. |
2339 | * Returns the difficulty level of the next solver that should be used, |
2340 | * or DIFF_MAX if no progress was made. */ |
2341 | static int parity_deductions(solver_state *sstate, |
2342 | grid_edge **edge_list, /* Edge list (from a face or a dot) */ |
2343 | int total_parity, /* Expected number of YESs modulo 2 (either 0 or 1) */ |
2344 | int unknown_count) |
6193da8d |
2345 | { |
121aae4b |
2346 | game_state *state = sstate->state; |
7c95608a |
2347 | int diff = DIFF_MAX; |
315e47b9 |
2348 | int *linedsf = sstate->linedsf; |
7c95608a |
2349 | |
2350 | if (unknown_count == 2) { |
2351 | /* Lines are known alike/opposite, depending on inv. */ |
2352 | int e[2]; |
2353 | find_unknowns(state, edge_list, 2, e); |
2354 | if (merge_lines(sstate, e[0], e[1], total_parity)) |
2355 | diff = min(diff, DIFF_HARD); |
2356 | } else if (unknown_count == 3) { |
2357 | int e[3]; |
2358 | int can[3]; /* canonical edges */ |
2359 | int inv[3]; /* whether can[x] is inverse to e[x] */ |
2360 | find_unknowns(state, edge_list, 3, e); |
2361 | can[0] = edsf_canonify(linedsf, e[0], inv); |
2362 | can[1] = edsf_canonify(linedsf, e[1], inv+1); |
2363 | can[2] = edsf_canonify(linedsf, e[2], inv+2); |
2364 | if (can[0] == can[1]) { |
2365 | if (solver_set_line(sstate, e[2], (total_parity^inv[0]^inv[1]) ? |
2366 | LINE_YES : LINE_NO)) |
2367 | diff = min(diff, DIFF_EASY); |
2368 | } |
2369 | if (can[0] == can[2]) { |
2370 | if (solver_set_line(sstate, e[1], (total_parity^inv[0]^inv[2]) ? |
2371 | LINE_YES : LINE_NO)) |
2372 | diff = min(diff, DIFF_EASY); |
2373 | } |
2374 | if (can[1] == can[2]) { |
2375 | if (solver_set_line(sstate, e[0], (total_parity^inv[1]^inv[2]) ? |
2376 | LINE_YES : LINE_NO)) |
2377 | diff = min(diff, DIFF_EASY); |
2378 | } |
2379 | } else if (unknown_count == 4) { |
2380 | int e[4]; |
2381 | int can[4]; /* canonical edges */ |
2382 | int inv[4]; /* whether can[x] is inverse to e[x] */ |
2383 | find_unknowns(state, edge_list, 4, e); |
2384 | can[0] = edsf_canonify(linedsf, e[0], inv); |
2385 | can[1] = edsf_canonify(linedsf, e[1], inv+1); |
2386 | can[2] = edsf_canonify(linedsf, e[2], inv+2); |
2387 | can[3] = edsf_canonify(linedsf, e[3], inv+3); |
2388 | if (can[0] == can[1]) { |
2389 | if (merge_lines(sstate, e[2], e[3], total_parity^inv[0]^inv[1])) |
2390 | diff = min(diff, DIFF_HARD); |
2391 | } else if (can[0] == can[2]) { |
2392 | if (merge_lines(sstate, e[1], e[3], total_parity^inv[0]^inv[2])) |
2393 | diff = min(diff, DIFF_HARD); |
2394 | } else if (can[0] == can[3]) { |
2395 | if (merge_lines(sstate, e[1], e[2], total_parity^inv[0]^inv[3])) |
2396 | diff = min(diff, DIFF_HARD); |
2397 | } else if (can[1] == can[2]) { |
2398 | if (merge_lines(sstate, e[0], e[3], total_parity^inv[1]^inv[2])) |
2399 | diff = min(diff, DIFF_HARD); |
2400 | } else if (can[1] == can[3]) { |
2401 | if (merge_lines(sstate, e[0], e[2], total_parity^inv[1]^inv[3])) |
2402 | diff = min(diff, DIFF_HARD); |
2403 | } else if (can[2] == can[3]) { |
2404 | if (merge_lines(sstate, e[0], e[1], total_parity^inv[2]^inv[3])) |
2405 | diff = min(diff, DIFF_HARD); |
6193da8d |
2406 | } |
2407 | } |
7c95608a |
2408 | return diff; |
6193da8d |
2409 | } |
2410 | |
7c95608a |
2411 | |
121aae4b |
2412 | /* |
7c95608a |
2413 | * These are the main solver functions. |
121aae4b |
2414 | * |
2415 | * Their return values are diff values corresponding to the lowest mode solver |
2416 | * that would notice the work that they have done. For example if the normal |
2417 | * mode solver adds actual lines or crosses, it will return DIFF_EASY as the |
2418 | * easy mode solver might be able to make progress using that. It doesn't make |
2419 | * sense for one of them to return a diff value higher than that of the |
7c95608a |
2420 | * function itself. |
121aae4b |
2421 | * |
2422 | * Each function returns the lowest value it can, as early as possible, in |
2423 | * order to try and pass as much work as possible back to the lower level |
2424 | * solvers which progress more quickly. |
2425 | */ |
6193da8d |
2426 | |
121aae4b |
2427 | /* PROPOSED NEW DESIGN: |
2428 | * We have a work queue consisting of 'events' notifying us that something has |
2429 | * happened that a particular solver mode might be interested in. For example |
2430 | * the hard mode solver might do something that helps the normal mode solver at |
2431 | * dot [x,y] in which case it will enqueue an event recording this fact. Then |
2432 | * we pull events off the work queue, and hand each in turn to the solver that |
2433 | * is interested in them. If a solver reports that it failed we pass the same |
2434 | * event on to progressively more advanced solvers and the loop detector. Once |
2435 | * we've exhausted an event, or it has helped us progress, we drop it and |
2436 | * continue to the next one. The events are sorted first in order of solver |
2437 | * complexity (easy first) then order of insertion (oldest first). |
2438 | * Once we run out of events we loop over each permitted solver in turn |
2439 | * (easiest first) until either a deduction is made (and an event therefore |
2440 | * emerges) or no further deductions can be made (in which case we've failed). |
2441 | * |
7c95608a |
2442 | * QUESTIONS: |
121aae4b |
2443 | * * How do we 'loop over' a solver when both dots and squares are concerned. |
2444 | * Answer: first all squares then all dots. |
2445 | */ |
2446 | |
315e47b9 |
2447 | static int trivial_deductions(solver_state *sstate) |
6193da8d |
2448 | { |
7c95608a |
2449 | int i, current_yes, current_no; |
2450 | game_state *state = sstate->state; |
2451 | grid *g = state->game_grid; |
1a739e2f |
2452 | int diff = DIFF_MAX; |
6193da8d |
2453 | |
7c95608a |
2454 | /* Per-face deductions */ |
2455 | for (i = 0; i < g->num_faces; i++) { |
2456 | grid_face *f = g->faces + i; |
2457 | |
2458 | if (sstate->face_solved[i]) |
121aae4b |
2459 | continue; |
6193da8d |
2460 | |
7c95608a |
2461 | current_yes = sstate->face_yes_count[i]; |
2462 | current_no = sstate->face_no_count[i]; |
c0eb17ce |
2463 | |
7c95608a |
2464 | if (current_yes + current_no == f->order) { |
2465 | sstate->face_solved[i] = TRUE; |
121aae4b |
2466 | continue; |
2467 | } |
6193da8d |
2468 | |
7c95608a |
2469 | if (state->clues[i] < 0) |
121aae4b |
2470 | continue; |
6193da8d |
2471 | |
dba1fdaf |
2472 | /* |
2473 | * This code checks whether the numeric clue on a face is so |
2474 | * large as to permit all its remaining LINE_UNKNOWNs to be |
2475 | * filled in as LINE_YES, or alternatively so small as to |
2476 | * permit them all to be filled in as LINE_NO. |
2477 | */ |
2478 | |
7c95608a |
2479 | if (state->clues[i] < current_yes) { |
121aae4b |
2480 | sstate->solver_status = SOLVER_MISTAKE; |
2481 | return DIFF_EASY; |
2482 | } |
7c95608a |
2483 | if (state->clues[i] == current_yes) { |
2484 | if (face_setall(sstate, i, LINE_UNKNOWN, LINE_NO)) |
121aae4b |
2485 | diff = min(diff, DIFF_EASY); |
7c95608a |
2486 | sstate->face_solved[i] = TRUE; |
121aae4b |
2487 | continue; |
2488 | } |
c0eb17ce |
2489 | |
7c95608a |
2490 | if (f->order - state->clues[i] < current_no) { |
121aae4b |
2491 | sstate->solver_status = SOLVER_MISTAKE; |
2492 | return DIFF_EASY; |
2493 | } |
7c95608a |
2494 | if (f->order - state->clues[i] == current_no) { |
2495 | if (face_setall(sstate, i, LINE_UNKNOWN, LINE_YES)) |
121aae4b |
2496 | diff = min(diff, DIFF_EASY); |
7c95608a |
2497 | sstate->face_solved[i] = TRUE; |
121aae4b |
2498 | continue; |
2499 | } |
dba1fdaf |
2500 | |
2501 | if (f->order - state->clues[i] == current_no + 1 && |
2502 | f->order - current_yes - current_no > 2) { |
2503 | /* |
2504 | * One small refinement to the above: we also look for any |
2505 | * adjacent pair of LINE_UNKNOWNs around the face with |
2506 | * some LINE_YES incident on it from elsewhere. If we find |
2507 | * one, then we know that pair of LINE_UNKNOWNs can't |
2508 | * _both_ be LINE_YES, and hence that pushes us one line |
2509 | * closer to being able to determine all the rest. |
2510 | */ |
2511 | int j, k, e1, e2, e, d; |
2512 | |
2513 | for (j = 0; j < f->order; j++) { |
2514 | e1 = f->edges[j] - g->edges; |
2515 | e2 = f->edges[j+1 < f->order ? j+1 : 0] - g->edges; |
2516 | |
2517 | if (g->edges[e1].dot1 == g->edges[e2].dot1 || |
2518 | g->edges[e1].dot1 == g->edges[e2].dot2) { |
2519 | d = g->edges[e1].dot1 - g->dots; |
2520 | } else { |
2521 | assert(g->edges[e1].dot2 == g->edges[e2].dot1 || |
2522 | g->edges[e1].dot2 == g->edges[e2].dot2); |
2523 | d = g->edges[e1].dot2 - g->dots; |
2524 | } |
2525 | |
2526 | if (state->lines[e1] == LINE_UNKNOWN && |
2527 | state->lines[e2] == LINE_UNKNOWN) { |
2528 | for (k = 0; k < g->dots[d].order; k++) { |
2529 | int e = g->dots[d].edges[k] - g->edges; |
2530 | if (state->lines[e] == LINE_YES) |
2531 | goto found; /* multi-level break */ |
2532 | } |
2533 | } |
2534 | } |
2535 | continue; |
2536 | |
2537 | found: |
2538 | /* |
2539 | * If we get here, we've found such a pair of edges, and |
2540 | * they're e1 and e2. |
2541 | */ |
2542 | for (j = 0; j < f->order; j++) { |
2543 | e = f->edges[j] - g->edges; |
2544 | if (state->lines[e] == LINE_UNKNOWN && e != e1 && e != e2) { |
2545 | int r = solver_set_line(sstate, e, LINE_YES); |
2546 | assert(r); |
2547 | diff = min(diff, DIFF_EASY); |
2548 | } |
2549 | } |
2550 | } |
121aae4b |
2551 | } |
6193da8d |
2552 | |
121aae4b |
2553 | check_caches(sstate); |
6193da8d |
2554 | |
121aae4b |
2555 | /* Per-dot deductions */ |
7c95608a |
2556 | for (i = 0; i < g->num_dots; i++) { |
2557 | grid_dot *d = g->dots + i; |
2558 | int yes, no, unknown; |
2559 | |
2560 | if (sstate->dot_solved[i]) |
121aae4b |
2561 | continue; |
c0eb17ce |
2562 | |
7c95608a |
2563 | yes = sstate->dot_yes_count[i]; |
2564 | no = sstate->dot_no_count[i]; |
2565 | unknown = d->order - yes - no; |
2566 | |
2567 | if (yes == 0) { |
2568 | if (unknown == 0) { |
2569 | sstate->dot_solved[i] = TRUE; |
2570 | } else if (unknown == 1) { |
2571 | dot_setall(sstate, i, LINE_UNKNOWN, LINE_NO); |
121aae4b |
2572 | diff = min(diff, DIFF_EASY); |
7c95608a |
2573 | sstate->dot_solved[i] = TRUE; |
2574 | } |
2575 | } else if (yes == 1) { |
2576 | if (unknown == 0) { |
121aae4b |
2577 | sstate->solver_status = SOLVER_MISTAKE; |
2578 | return DIFF_EASY; |
7c95608a |
2579 | } else if (unknown == 1) { |
2580 | dot_setall(sstate, i, LINE_UNKNOWN, LINE_YES); |
2581 | diff = min(diff, DIFF_EASY); |
2582 | } |
2583 | } else if (yes == 2) { |
2584 | if (unknown > 0) { |
2585 | dot_setall(sstate, i, LINE_UNKNOWN, LINE_NO); |
2586 | diff = min(diff, DIFF_EASY); |
2587 | } |
2588 | sstate->dot_solved[i] = TRUE; |
2589 | } else { |
2590 | sstate->solver_status = SOLVER_MISTAKE; |
2591 | return DIFF_EASY; |
6193da8d |
2592 | } |
2593 | } |
6193da8d |
2594 | |
121aae4b |
2595 | check_caches(sstate); |
6193da8d |
2596 | |
121aae4b |
2597 | return diff; |
6193da8d |
2598 | } |
2599 | |
315e47b9 |
2600 | static int dline_deductions(solver_state *sstate) |
6193da8d |
2601 | { |
121aae4b |
2602 | game_state *state = sstate->state; |
7c95608a |
2603 | grid *g = state->game_grid; |
315e47b9 |
2604 | char *dlines = sstate->dlines; |
7c95608a |
2605 | int i; |
1a739e2f |
2606 | int diff = DIFF_MAX; |
6193da8d |
2607 | |
7c95608a |
2608 | /* ------ Face deductions ------ */ |
2609 | |
2610 | /* Given a set of dline atmostone/atleastone constraints, need to figure |
2611 | * out if we can deduce any further info. For more general faces than |
2612 | * squares, this turns out to be a tricky problem. |
2613 | * The approach taken here is to define (per face) NxN matrices: |
2614 | * "maxs" and "mins". |
2615 | * The entries maxs(j,k) and mins(j,k) define the upper and lower limits |
2616 | * for the possible number of edges that are YES between positions j and k |
2617 | * going clockwise around the face. Can think of j and k as marking dots |
2618 | * around the face (recall the labelling scheme: edge0 joins dot0 to dot1, |
2619 | * edge1 joins dot1 to dot2 etc). |
2620 | * Trivially, mins(j,j) = maxs(j,j) = 0, and we don't even bother storing |
2621 | * these. mins(j,j+1) and maxs(j,j+1) are determined by whether edge{j} |
2622 | * is YES, NO or UNKNOWN. mins(j,j+2) and maxs(j,j+2) are related to |
2623 | * the dline atmostone/atleastone status for edges j and j+1. |
2624 | * |
2625 | * Then we calculate the remaining entries recursively. We definitely |
2626 | * know that |
2627 | * mins(j,k) >= { mins(j,u) + mins(u,k) } for any u between j and k. |
2628 | * This is because any valid placement of YESs between j and k must give |
2629 | * a valid placement between j and u, and also between u and k. |
2630 | * I believe it's sufficient to use just the two values of u: |
2631 | * j+1 and j+2. Seems to work well in practice - the bounds we compute |
2632 | * are rigorous, even if they might not be best-possible. |
2633 | * |
2634 | * Once we have maxs and mins calculated, we can make inferences about |
2635 | * each dline{j,j+1} by looking at the possible complementary edge-counts |
2636 | * mins(j+2,j) and maxs(j+2,j) and comparing these with the face clue. |
2637 | * As well as dlines, we can make similar inferences about single edges. |
2638 | * For example, consider a pentagon with clue 3, and we know at most one |
2639 | * of (edge0, edge1) is YES, and at most one of (edge2, edge3) is YES. |
2640 | * We could then deduce edge4 is YES, because maxs(0,4) would be 2, so |
2641 | * that final edge would have to be YES to make the count up to 3. |
2642 | */ |
121aae4b |
2643 | |
7c95608a |
2644 | /* Much quicker to allocate arrays on the stack than the heap, so |
2645 | * define the largest possible face size, and base our array allocations |
2646 | * on that. We check this with an assertion, in case someone decides to |
2647 | * make a grid which has larger faces than this. Note, this algorithm |
2648 | * could get quite expensive if there are many large faces. */ |
918a098a |
2649 | #define MAX_FACE_SIZE 12 |
7c95608a |
2650 | |
2651 | for (i = 0; i < g->num_faces; i++) { |
2652 | int maxs[MAX_FACE_SIZE][MAX_FACE_SIZE]; |
2653 | int mins[MAX_FACE_SIZE][MAX_FACE_SIZE]; |
2654 | grid_face *f = g->faces + i; |
2655 | int N = f->order; |
2656 | int j,m; |
2657 | int clue = state->clues[i]; |
2658 | assert(N <= MAX_FACE_SIZE); |
2659 | if (sstate->face_solved[i]) |
6193da8d |
2660 | continue; |
7c95608a |
2661 | if (clue < 0) continue; |
2662 | |
2663 | /* Calculate the (j,j+1) entries */ |
2664 | for (j = 0; j < N; j++) { |
2665 | int edge_index = f->edges[j] - g->edges; |
2666 | int dline_index; |
2667 | enum line_state line1 = state->lines[edge_index]; |
2668 | enum line_state line2; |
2669 | int tmp; |
2670 | int k = j + 1; |
2671 | if (k >= N) k = 0; |
2672 | maxs[j][k] = (line1 == LINE_NO) ? 0 : 1; |
2673 | mins[j][k] = (line1 == LINE_YES) ? 1 : 0; |
2674 | /* Calculate the (j,j+2) entries */ |
2675 | dline_index = dline_index_from_face(g, f, k); |
2676 | edge_index = f->edges[k] - g->edges; |
2677 | line2 = state->lines[edge_index]; |
2678 | k++; |
2679 | if (k >= N) k = 0; |
2680 | |
2681 | /* max */ |
2682 | tmp = 2; |
2683 | if (line1 == LINE_NO) tmp--; |
2684 | if (line2 == LINE_NO) tmp--; |
2685 | if (tmp == 2 && is_atmostone(dlines, dline_index)) |
2686 | tmp = 1; |
2687 | maxs[j][k] = tmp; |
2688 | |
2689 | /* min */ |
2690 | tmp = 0; |
2691 | if (line1 == LINE_YES) tmp++; |
2692 | if (line2 == LINE_YES) tmp++; |
2693 | if (tmp == 0 && is_atleastone(dlines, dline_index)) |
2694 | tmp = 1; |
2695 | mins[j][k] = tmp; |
2696 | } |
121aae4b |
2697 | |
7c95608a |
2698 | /* Calculate the (j,j+m) entries for m between 3 and N-1 */ |
2699 | for (m = 3; m < N; m++) { |
2700 | for (j = 0; j < N; j++) { |
2701 | int k = j + m; |
2702 | int u = j + 1; |
2703 | int v = j + 2; |
2704 | int tmp; |
2705 | if (k >= N) k -= N; |
2706 | if (u >= N) u -= N; |
2707 | if (v >= N) v -= N; |
2708 | maxs[j][k] = maxs[j][u] + maxs[u][k]; |
2709 | mins[j][k] = mins[j][u] + mins[u][k]; |
2710 | tmp = maxs[j][v] + maxs[v][k]; |
2711 | maxs[j][k] = min(maxs[j][k], tmp); |
2712 | tmp = mins[j][v] + mins[v][k]; |
2713 | mins[j][k] = max(mins[j][k], tmp); |
2714 | } |
2715 | } |
121aae4b |
2716 | |
7c95608a |
2717 | /* See if we can make any deductions */ |
2718 | for (j = 0; j < N; j++) { |
2719 | int k; |
2720 | grid_edge *e = f->edges[j]; |
2721 | int line_index = e - g->edges; |
2722 | int dline_index; |
121aae4b |
2723 | |
7c95608a |
2724 | if (state->lines[line_index] != LINE_UNKNOWN) |
2725 | continue; |
2726 | k = j + 1; |
2727 | if (k >= N) k = 0; |
121aae4b |
2728 | |
7c95608a |
2729 | /* minimum YESs in the complement of this edge */ |
2730 | if (mins[k][j] > clue) { |
2731 | sstate->solver_status = SOLVER_MISTAKE; |
2732 | return DIFF_EASY; |
2733 | } |
2734 | if (mins[k][j] == clue) { |
2735 | /* setting this edge to YES would make at least |
2736 | * (clue+1) edges - contradiction */ |
2737 | solver_set_line(sstate, line_index, LINE_NO); |
2738 | diff = min(diff, DIFF_EASY); |
2739 | } |
2740 | if (maxs[k][j] < clue - 1) { |
2741 | sstate->solver_status = SOLVER_MISTAKE; |
2742 | return DIFF_EASY; |
2743 | } |
2744 | if (maxs[k][j] == clue - 1) { |
2745 | /* Only way to satisfy the clue is to set edge{j} as YES */ |
2746 | solver_set_line(sstate, line_index, LINE_YES); |
2747 | diff = min(diff, DIFF_EASY); |
2748 | } |
2749 | |
315e47b9 |
2750 | /* More advanced deduction that allows propagation along diagonal |
2751 | * chains of faces connected by dots, for example, 3-2-...-2-3 |
2752 | * in square grids. */ |
2753 | if (sstate->diff >= DIFF_TRICKY) { |
2754 | /* Now see if we can make dline deduction for edges{j,j+1} */ |
2755 | e = f->edges[k]; |
2756 | if (state->lines[e - g->edges] != LINE_UNKNOWN) |
2757 | /* Only worth doing this for an UNKNOWN,UNKNOWN pair. |
2758 | * Dlines where one of the edges is known, are handled in the |
2759 | * dot-deductions */ |
2760 | continue; |
2761 | |
2762 | dline_index = dline_index_from_face(g, f, k); |
2763 | k++; |
2764 | if (k >= N) k = 0; |
2765 | |
2766 | /* minimum YESs in the complement of this dline */ |
2767 | if (mins[k][j] > clue - 2) { |
2768 | /* Adding 2 YESs would break the clue */ |
2769 | if (set_atmostone(dlines, dline_index)) |
2770 | diff = min(diff, DIFF_NORMAL); |
2771 | } |
2772 | /* maximum YESs in the complement of this dline */ |
2773 | if (maxs[k][j] < clue) { |
2774 | /* Adding 2 NOs would mean not enough YESs */ |
2775 | if (set_atleastone(dlines, dline_index)) |
2776 | diff = min(diff, DIFF_NORMAL); |
2777 | } |
7c95608a |
2778 | } |
6193da8d |
2779 | } |
6193da8d |
2780 | } |
2781 | |
121aae4b |
2782 | if (diff < DIFF_NORMAL) |
2783 | return diff; |
6193da8d |
2784 | |
7c95608a |
2785 | /* ------ Dot deductions ------ */ |
6193da8d |
2786 | |
7c95608a |
2787 | for (i = 0; i < g->num_dots; i++) { |
2788 | grid_dot *d = g->dots + i; |
2789 | int N = d->order; |
2790 | int yes, no, unknown; |
2791 | int j; |
2792 | if (sstate->dot_solved[i]) |
2793 | continue; |
2794 | yes = sstate->dot_yes_count[i]; |
2795 | no = sstate->dot_no_count[i]; |
2796 | unknown = N - yes - no; |
2797 | |
2798 | for (j = 0; j < N; j++) { |
2799 | int k; |
2800 | int dline_index; |
2801 | int line1_index, line2_index; |
2802 | enum line_state line1, line2; |
2803 | k = j + 1; |
2804 | if (k >= N) k = 0; |
2805 | dline_index = dline_index_from_dot(g, d, j); |
2806 | line1_index = d->edges[j] - g->edges; |
2807 | line2_index = d->edges[k] - g->edges; |
2808 | line1 = state->lines[line1_index]; |
2809 | line2 = state->lines[line2_index]; |
2810 | |
2811 | /* Infer dline state from line state */ |
2812 | if (line1 == LINE_NO || line2 == LINE_NO) { |
2813 | if (set_atmostone(dlines, dline_index)) |
2814 | diff = min(diff, DIFF_NORMAL); |
2815 | } |
2816 | if (line1 == LINE_YES || line2 == LINE_YES) { |
2817 | if (set_atleastone(dlines, dline_index)) |
2818 | diff = min(diff, DIFF_NORMAL); |
2819 | } |
2820 | /* Infer line state from dline state */ |
2821 | if (is_atmostone(dlines, dline_index)) { |
2822 | if (line1 == LINE_YES && line2 == LINE_UNKNOWN) { |
2823 | solver_set_line(sstate, line2_index, LINE_NO); |
2824 | diff = min(diff, DIFF_EASY); |
2825 | } |
2826 | if (line2 == LINE_YES && line1 == LINE_UNKNOWN) { |
2827 | solver_set_line(sstate, line1_index, LINE_NO); |
2828 | diff = min(diff, DIFF_EASY); |
2829 | } |
2830 | } |
2831 | if (is_atleastone(dlines, dline_index)) { |
2832 | if (line1 == LINE_NO && line2 == LINE_UNKNOWN) { |
2833 | solver_set_line(sstate, line2_index, LINE_YES); |
2834 | diff = min(diff, DIFF_EASY); |
2835 | } |
2836 | if (line2 == LINE_NO && line1 == LINE_UNKNOWN) { |
2837 | solver_set_line(sstate, line1_index, LINE_YES); |
2838 | diff = min(diff, DIFF_EASY); |
2839 | } |
2840 | } |
2841 | /* Deductions that depend on the numbers of lines. |
2842 | * Only bother if both lines are UNKNOWN, otherwise the |
2843 | * easy-mode solver (or deductions above) would have taken |
2844 | * care of it. */ |
2845 | if (line1 != LINE_UNKNOWN || line2 != LINE_UNKNOWN) |
2846 | continue; |
6193da8d |
2847 | |
7c95608a |
2848 | if (yes == 0 && unknown == 2) { |
2849 | /* Both these unknowns must be identical. If we know |
2850 | * atmostone or atleastone, we can make progress. */ |
2851 | if (is_atmostone(dlines, dline_index)) { |
2852 | solver_set_line(sstate, line1_index, LINE_NO); |
2853 | solver_set_line(sstate, line2_index, LINE_NO); |
2854 | diff = min(diff, DIFF_EASY); |
2855 | } |
2856 | if (is_atleastone(dlines, dline_index)) { |
2857 | solver_set_line(sstate, line1_index, LINE_YES); |
2858 | solver_set_line(sstate, line2_index, LINE_YES); |
2859 | diff = min(diff, DIFF_EASY); |
2860 | } |
2861 | } |
2862 | if (yes == 1) { |
2863 | if (set_atmostone(dlines, dline_index)) |
2864 | diff = min(diff, DIFF_NORMAL); |
2865 | if (unknown == 2) { |
2866 | if (set_atleastone(dlines, dline_index)) |
2867 | diff = min(diff, DIFF_NORMAL); |
2868 | } |
121aae4b |
2869 | } |
6193da8d |
2870 | |
315e47b9 |
2871 | /* More advanced deduction that allows propagation along diagonal |
2872 | * chains of faces connected by dots, for example: 3-2-...-2-3 |
2873 | * in square grids. */ |
2874 | if (sstate->diff >= DIFF_TRICKY) { |
2875 | /* If we have atleastone set for this dline, infer |
2876 | * atmostone for each "opposite" dline (that is, each |
2877 | * dline without edges in common with this one). |
2878 | * Again, this test is only worth doing if both these |
2879 | * lines are UNKNOWN. For if one of these lines were YES, |
2880 | * the (yes == 1) test above would kick in instead. */ |
2881 | if (is_atleastone(dlines, dline_index)) { |
2882 | int opp; |
2883 | for (opp = 0; opp < N; opp++) { |
2884 | int opp_dline_index; |
2885 | if (opp == j || opp == j+1 || opp == j-1) |
2886 | continue; |
2887 | if (j == 0 && opp == N-1) |
2888 | continue; |
2889 | if (j == N-1 && opp == 0) |
2890 | continue; |
2891 | opp_dline_index = dline_index_from_dot(g, d, opp); |
2892 | if (set_atmostone(dlines, opp_dline_index)) |
2893 | diff = min(diff, DIFF_NORMAL); |
2894 | } |
2895 | if (yes == 0 && is_atmostone(dlines, dline_index)) { |
2896 | /* This dline has *exactly* one YES and there are no |
2897 | * other YESs. This allows more deductions. */ |
2898 | if (unknown == 3) { |
2899 | /* Third unknown must be YES */ |
2900 | for (opp = 0; opp < N; opp++) { |
2901 | int opp_index; |
2902 | if (opp == j || opp == k) |
2903 | continue; |
2904 | opp_index = d->edges[opp] - g->edges; |
2905 | if (state->lines[opp_index] == LINE_UNKNOWN) { |
2906 | solver_set_line(sstate, opp_index, |
2907 | LINE_YES); |
2908 | diff = min(diff, DIFF_EASY); |
2909 | } |
121aae4b |
2910 | } |
315e47b9 |
2911 | } else if (unknown == 4) { |
2912 | /* Exactly one of opposite UNKNOWNS is YES. We've |
2913 | * already set atmostone, so set atleastone as |
2914 | * well. |
2915 | */ |
2916 | if (dline_set_opp_atleastone(sstate, d, j)) |
2917 | diff = min(diff, DIFF_NORMAL); |
121aae4b |
2918 | } |
2919 | } |
121aae4b |
2920 | } |
6193da8d |
2921 | } |
6193da8d |
2922 | } |
121aae4b |
2923 | } |
121aae4b |
2924 | return diff; |
6193da8d |
2925 | } |
2926 | |
315e47b9 |
2927 | static int linedsf_deductions(solver_state *sstate) |
6193da8d |
2928 | { |
121aae4b |
2929 | game_state *state = sstate->state; |
7c95608a |
2930 | grid *g = state->game_grid; |
315e47b9 |
2931 | char *dlines = sstate->dlines; |
7c95608a |
2932 | int i; |
1a739e2f |
2933 | int diff = DIFF_MAX; |
7c95608a |
2934 | int diff_tmp; |
121aae4b |
2935 | |
7c95608a |
2936 | /* ------ Face deductions ------ */ |
6193da8d |
2937 | |
7c95608a |
2938 | /* A fully-general linedsf deduction seems overly complicated |
2939 | * (I suspect the problem is NP-complete, though in practice it might just |
2940 | * be doable because faces are limited in size). |
2941 | * For simplicity, we only consider *pairs* of LINE_UNKNOWNS that are |
2942 | * known to be identical. If setting them both to YES (or NO) would break |
2943 | * the clue, set them to NO (or YES). */ |
121aae4b |
2944 | |
7c95608a |
2945 | for (i = 0; i < g->num_faces; i++) { |
2946 | int N, yes, no, unknown; |
2947 | int clue; |
6193da8d |
2948 | |
7c95608a |
2949 | if (sstate->face_solved[i]) |
121aae4b |
2950 | continue; |
7c95608a |
2951 | clue = state->clues[i]; |
2952 | if (clue < 0) |
121aae4b |
2953 | continue; |
6193da8d |
2954 | |
7c95608a |
2955 | N = g->faces[i].order; |
2956 | yes = sstate->face_yes_count[i]; |
2957 | if (yes + 1 == clue) { |
2958 | if (face_setall_identical(sstate, i, LINE_NO)) |
2959 | diff = min(diff, DIFF_EASY); |
121aae4b |
2960 | } |
7c95608a |
2961 | no = sstate->face_no_count[i]; |
2962 | if (no + 1 == N - clue) { |
2963 | if (face_setall_identical(sstate, i, LINE_YES)) |
2964 | diff = min(diff, DIFF_EASY); |
6193da8d |
2965 | } |
6193da8d |
2966 | |
7c95608a |
2967 | /* Reload YES count, it might have changed */ |
2968 | yes = sstate->face_yes_count[i]; |
2969 | unknown = N - no - yes; |
2970 | |
2971 | /* Deductions with small number of LINE_UNKNOWNs, based on overall |
2972 | * parity of lines. */ |
2973 | diff_tmp = parity_deductions(sstate, g->faces[i].edges, |
2974 | (clue - yes) % 2, unknown); |
2975 | diff = min(diff, diff_tmp); |
2976 | } |
2977 | |
2978 | /* ------ Dot deductions ------ */ |
2979 | for (i = 0; i < g->num_dots; i++) { |
2980 | grid_dot *d = g->dots + i; |
2981 | int N = d->order; |
2982 | int j; |
2983 | int yes, no, unknown; |
2984 | /* Go through dlines, and do any dline<->linedsf deductions wherever |
2985 | * we find two UNKNOWNS. */ |
2986 | for (j = 0; j < N; j++) { |
2987 | int dline_index = dline_index_from_dot(g, d, j); |
2988 | int line1_index; |
2989 | int line2_index; |
2990 | int can1, can2, inv1, inv2; |
2991 | int j2; |
2992 | line1_index = d->edges[j] - g->edges; |
2993 | if (state->lines[line1_index] != LINE_UNKNOWN) |
121aae4b |
2994 | continue; |
7c95608a |
2995 | j2 = j + 1; |
2996 | if (j2 == N) j2 = 0; |
2997 | line2_index = d->edges[j2] - g->edges; |
2998 | if (state->lines[line2_index] != LINE_UNKNOWN) |
121aae4b |
2999 | continue; |
7c95608a |
3000 | /* Infer dline flags from linedsf */ |
315e47b9 |
3001 | can1 = edsf_canonify(sstate->linedsf, line1_index, &inv1); |
3002 | can2 = edsf_canonify(sstate->linedsf, line2_index, &inv2); |
7c95608a |
3003 | if (can1 == can2 && inv1 != inv2) { |
3004 | /* These are opposites, so set dline atmostone/atleastone */ |
3005 | if (set_atmostone(dlines, dline_index)) |
3006 | diff = min(diff, DIFF_NORMAL); |
3007 | if (set_atleastone(dlines, dline_index)) |
3008 | diff = min(diff, DIFF_NORMAL); |
121aae4b |
3009 | continue; |
7c95608a |
3010 | } |
3011 | /* Infer linedsf from dline flags */ |
3012 | if (is_atmostone(dlines, dline_index) |
3013 | && is_atleastone(dlines, dline_index)) { |
3014 | if (merge_lines(sstate, line1_index, line2_index, 1)) |
121aae4b |
3015 | diff = min(diff, DIFF_HARD); |
121aae4b |
3016 | } |
3017 | } |
7c95608a |
3018 | |
3019 | /* Deductions with small number of LINE_UNKNOWNs, based on overall |
3020 | * parity of lines. */ |
3021 | yes = sstate->dot_yes_count[i]; |
3022 | no = sstate->dot_no_count[i]; |
3023 | unknown = N - yes - no; |
3024 | diff_tmp = parity_deductions(sstate, d->edges, |
3025 | yes % 2, unknown); |
3026 | diff = min(diff, diff_tmp); |
121aae4b |
3027 | } |
6193da8d |
3028 | |
7c95608a |
3029 | /* ------ Edge dsf deductions ------ */ |
3030 | |
3031 | /* If the state of a line is known, deduce the state of its canonical line |
3032 | * too, and vice versa. */ |
3033 | for (i = 0; i < g->num_edges; i++) { |
3034 | int can, inv; |
3035 | enum line_state s; |
315e47b9 |
3036 | can = edsf_canonify(sstate->linedsf, i, &inv); |
7c95608a |
3037 | if (can == i) |
3038 | continue; |
3039 | s = sstate->state->lines[can]; |
3040 | if (s != LINE_UNKNOWN) { |
3041 | if (solver_set_line(sstate, i, inv ? OPP(s) : s)) |
3042 | diff = min(diff, DIFF_EASY); |
3043 | } else { |
3044 | s = sstate->state->lines[i]; |
3045 | if (s != LINE_UNKNOWN) { |
3046 | if (solver_set_line(sstate, can, inv ? OPP(s) : s)) |
121aae4b |
3047 | diff = min(diff, DIFF_EASY); |
3048 | } |
3049 | } |
3050 | } |
6193da8d |
3051 | |
121aae4b |
3052 | return diff; |
3053 | } |
6193da8d |
3054 | |
121aae4b |
3055 | static int loop_deductions(solver_state *sstate) |
3056 | { |
3057 | int edgecount = 0, clues = 0, satclues = 0, sm1clues = 0; |
3058 | game_state *state = sstate->state; |
7c95608a |
3059 | grid *g = state->game_grid; |
3060 | int shortest_chainlen = g->num_dots; |
121aae4b |
3061 | int loop_found = FALSE; |
121aae4b |
3062 | int dots_connected; |
3063 | int progress = FALSE; |
7c95608a |
3064 | int i; |
6193da8d |
3065 | |
121aae4b |
3066 | /* |
3067 | * Go through the grid and update for all the new edges. |
3068 | * Since merge_dots() is idempotent, the simplest way to |
3069 | * do this is just to update for _all_ the edges. |
7c95608a |
3070 | * Also, while we're here, we count the edges. |
121aae4b |
3071 | */ |
7c95608a |
3072 | for (i = 0; i < g->num_edges; i++) { |
3073 | if (state->lines[i] == LINE_YES) { |
3074 | loop_found |= merge_dots(sstate, i); |
121aae4b |
3075 | edgecount++; |
3076 | } |
7c95608a |
3077 | } |
6193da8d |
3078 | |
7c95608a |
3079 | /* |
3080 | * Count the clues, count the satisfied clues, and count the |
3081 | * satisfied-minus-one clues. |
3082 | */ |
3083 | for (i = 0; i < g->num_faces; i++) { |
3084 | int c = state->clues[i]; |
3085 | if (c >= 0) { |
3086 | int o = sstate->face_yes_count[i]; |
121aae4b |
3087 | if (o == c) |
3088 | satclues++; |
3089 | else if (o == c-1) |
3090 | sm1clues++; |
3091 | clues++; |
3092 | } |
3093 | } |
6193da8d |
3094 | |
7c95608a |
3095 | for (i = 0; i < g->num_dots; ++i) { |
3096 | dots_connected = |
121aae4b |
3097 | sstate->looplen[dsf_canonify(sstate->dotdsf, i)]; |
3098 | if (dots_connected > 1) |
3099 | shortest_chainlen = min(shortest_chainlen, dots_connected); |
6193da8d |
3100 | } |
6193da8d |
3101 | |
121aae4b |
3102 | assert(sstate->solver_status == SOLVER_INCOMPLETE); |
6c42c563 |
3103 | |
121aae4b |
3104 | if (satclues == clues && shortest_chainlen == edgecount) { |
3105 | sstate->solver_status = SOLVER_SOLVED; |
3106 | /* This discovery clearly counts as progress, even if we haven't |
3107 | * just added any lines or anything */ |
7c95608a |
3108 | progress = TRUE; |
121aae4b |
3109 | goto finished_loop_deductionsing; |
3110 | } |
6193da8d |
3111 | |
121aae4b |
3112 | /* |
3113 | * Now go through looking for LINE_UNKNOWN edges which |
3114 | * connect two dots that are already in the same |
3115 | * equivalence class. If we find one, test to see if the |
3116 | * loop it would create is a solution. |
3117 | */ |
7c95608a |
3118 | for (i = 0; i < g->num_edges; i++) { |
3119 | grid_edge *e = g->edges + i; |
3120 | int d1 = e->dot1 - g->dots; |
3121 | int d2 = e->dot2 - g->dots; |
3122 | int eqclass, val; |
3123 | if (state->lines[i] != LINE_UNKNOWN) |
3124 | continue; |
121aae4b |
3125 | |
7c95608a |
3126 | eqclass = dsf_canonify(sstate->dotdsf, d1); |
3127 | if (eqclass != dsf_canonify(sstate->dotdsf, d2)) |
3128 | continue; |
121aae4b |
3129 | |
7c95608a |
3130 | val = LINE_NO; /* loop is bad until proven otherwise */ |
6193da8d |
3131 | |
7c95608a |
3132 | /* |
3133 | * This edge would form a loop. Next |
3134 | * question: how long would the loop be? |
3135 | * Would it equal the total number of edges |
3136 | * (plus the one we'd be adding if we added |
3137 | * it)? |
3138 | */ |
3139 | if (sstate->looplen[eqclass] == edgecount + 1) { |
3140 | int sm1_nearby; |
121aae4b |
3141 | |
3142 | /* |
7c95608a |
3143 | * This edge would form a loop which |
3144 | * took in all the edges in the entire |
3145 | * grid. So now we need to work out |
3146 | * whether it would be a valid solution |
3147 | * to the puzzle, which means we have to |
3148 | * check if it satisfies all the clues. |
3149 | * This means that every clue must be |
3150 | * either satisfied or satisfied-minus- |
3151 | * 1, and also that the number of |
3152 | * satisfied-minus-1 clues must be at |
3153 | * most two and they must lie on either |
3154 | * side of this edge. |
121aae4b |
3155 | */ |
7c95608a |
3156 | sm1_nearby = 0; |
3157 | if (e->face1) { |
3158 | int f = e->face1 - g->faces; |
3159 | int c = state->clues[f]; |
3160 | if (c >= 0 && sstate->face_yes_count[f] == c - 1) |
121aae4b |
3161 | sm1_nearby++; |
6c42c563 |
3162 | } |
7c95608a |
3163 | if (e->face2) { |
3164 | int f = e->face2 - g->faces; |
3165 | int c = state->clues[f]; |
3166 | if (c >= 0 && sstate->face_yes_count[f] == c - 1) |
3167 | sm1_nearby++; |
6c42c563 |
3168 | } |
7c95608a |
3169 | if (sm1clues == sm1_nearby && |
3170 | sm1clues + satclues == clues) { |
3171 | val = LINE_YES; /* loop is good! */ |
6c42c563 |
3172 | } |
121aae4b |
3173 | } |
7c95608a |
3174 | |
3175 | /* |
3176 | * Right. Now we know that adding this edge |
3177 | * would form a loop, and we know whether |
3178 | * that loop would be a viable solution or |
3179 | * not. |
3180 | * |
3181 | * If adding this edge produces a solution, |
3182 | * then we know we've found _a_ solution but |
3183 | * we don't know that it's _the_ solution - |
3184 | * if it were provably the solution then |
3185 | * we'd have deduced this edge some time ago |
3186 | * without the need to do loop detection. So |
3187 | * in this state we return SOLVER_AMBIGUOUS, |
3188 | * which has the effect that hitting Solve |
3189 | * on a user-provided puzzle will fill in a |
3190 | * solution but using the solver to |
3191 | * construct new puzzles won't consider this |
3192 | * a reasonable deduction for the user to |
3193 | * make. |
3194 | */ |
3195 | progress = solver_set_line(sstate, i, val); |
3196 | assert(progress == TRUE); |
3197 | if (val == LINE_YES) { |
3198 | sstate->solver_status = SOLVER_AMBIGUOUS; |
3199 | goto finished_loop_deductionsing; |
3200 | } |
6193da8d |
3201 | } |
6193da8d |
3202 | |
7c95608a |
3203 | finished_loop_deductionsing: |
121aae4b |
3204 | return progress ? DIFF_EASY : DIFF_MAX; |
c0eb17ce |
3205 | } |
6193da8d |
3206 | |
3207 | /* This will return a dynamically allocated solver_state containing the (more) |
3208 | * solved grid */ |
315e47b9 |
3209 | static solver_state *solve_game_rec(const solver_state *sstate_start) |
121aae4b |
3210 | { |
315e47b9 |
3211 | solver_state *sstate; |
6193da8d |
3212 | |
315e47b9 |
3213 | /* Index of the solver we should call next. */ |
3214 | int i = 0; |
3215 | |
3216 | /* As a speed-optimisation, we avoid re-running solvers that we know |
3217 | * won't make any progress. This happens when a high-difficulty |
3218 | * solver makes a deduction that can only help other high-difficulty |
3219 | * solvers. |
3220 | * For example: if a new 'dline' flag is set by dline_deductions, the |
3221 | * trivial_deductions solver cannot do anything with this information. |
3222 | * If we've already run the trivial_deductions solver (because it's |
3223 | * earlier in the list), there's no point running it again. |
3224 | * |
3225 | * Therefore: if a solver is earlier in the list than "threshold_index", |
3226 | * we don't bother running it if it's difficulty level is less than |
3227 | * "threshold_diff". |
3228 | */ |
3229 | int threshold_diff = 0; |
3230 | int threshold_index = 0; |
3231 | |
121aae4b |
3232 | sstate = dup_solver_state(sstate_start); |
7c95608a |
3233 | |
121aae4b |
3234 | check_caches(sstate); |
6193da8d |
3235 | |
315e47b9 |
3236 | while (i < NUM_SOLVERS) { |
121aae4b |
3237 | if (sstate->solver_status == SOLVER_MISTAKE) |
3238 | return sstate; |
7c95608a |
3239 | if (sstate->solver_status == SOLVER_SOLVED || |
121aae4b |
3240 | sstate->solver_status == SOLVER_AMBIGUOUS) { |
315e47b9 |
3241 | /* solver finished */ |
121aae4b |
3242 | break; |
3243 | } |
99dd160e |
3244 | |
315e47b9 |
3245 | if ((solver_diffs[i] >= threshold_diff || i >= threshold_index) |
3246 | && solver_diffs[i] <= sstate->diff) { |
3247 | /* current_solver is eligible, so use it */ |
3248 | int next_diff = solver_fns[i](sstate); |
3249 | if (next_diff != DIFF_MAX) { |
3250 | /* solver made progress, so use new thresholds and |
3251 | * start again at top of list. */ |
3252 | threshold_diff = next_diff; |
3253 | threshold_index = i; |
3254 | i = 0; |
3255 | continue; |
3256 | } |
3257 | } |
3258 | /* current_solver is ineligible, or failed to make progress, so |
3259 | * go to the next solver in the list */ |
3260 | i++; |
3261 | } |
121aae4b |
3262 | |
3263 | if (sstate->solver_status == SOLVER_SOLVED || |
3264 | sstate->solver_status == SOLVER_AMBIGUOUS) { |
3265 | /* s/LINE_UNKNOWN/LINE_NO/g */ |
7c95608a |
3266 | array_setall(sstate->state->lines, LINE_UNKNOWN, LINE_NO, |
3267 | sstate->state->game_grid->num_edges); |
121aae4b |
3268 | return sstate; |
3269 | } |
6193da8d |
3270 | |
121aae4b |
3271 | return sstate; |
6193da8d |
3272 | } |
3273 | |
6193da8d |
3274 | static char *solve_game(game_state *state, game_state *currstate, |
3275 | char *aux, char **error) |
3276 | { |
3277 | char *soln = NULL; |
3278 | solver_state *sstate, *new_sstate; |
3279 | |
121aae4b |
3280 | sstate = new_solver_state(state, DIFF_MAX); |
315e47b9 |
3281 | new_sstate = solve_game_rec(sstate); |
6193da8d |
3282 | |
3283 | if (new_sstate->solver_status == SOLVER_SOLVED) { |
3284 | soln = encode_solve_move(new_sstate->state); |
3285 | } else if (new_sstate->solver_status == SOLVER_AMBIGUOUS) { |
3286 | soln = encode_solve_move(new_sstate->state); |
3287 | /**error = "Solver found ambiguous solutions"; */ |
3288 | } else { |
3289 | soln = encode_solve_move(new_sstate->state); |
3290 | /**error = "Solver failed"; */ |
3291 | } |
3292 | |
3293 | free_solver_state(new_sstate); |
3294 | free_solver_state(sstate); |
3295 | |
3296 | return soln; |
3297 | } |
3298 | |
121aae4b |
3299 | /* ---------------------------------------------------------------------- |
3300 | * Drawing and mouse-handling |
3301 | */ |
6193da8d |
3302 | |
3303 | static char *interpret_move(game_state *state, game_ui *ui, game_drawstate *ds, |
3304 | int x, int y, int button) |
3305 | { |
7c95608a |
3306 | grid *g = state->game_grid; |
3307 | grid_edge *e; |
3308 | int i; |
6193da8d |
3309 | char *ret, buf[80]; |
3310 | char button_char = ' '; |
3311 | enum line_state old_state; |
3312 | |
3313 | button &= ~MOD_MASK; |
3314 | |
7c95608a |
3315 | /* Convert mouse-click (x,y) to grid coordinates */ |
3316 | x -= BORDER(ds->tilesize); |
3317 | y -= BORDER(ds->tilesize); |
3318 | x = x * g->tilesize / ds->tilesize; |
3319 | y = y * g->tilesize / ds->tilesize; |
3320 | x += g->lowest_x; |
3321 | y += g->lowest_y; |
6193da8d |
3322 | |
7c95608a |
3323 | e = grid_nearest_edge(g, x, y); |
3324 | if (e == NULL) |
6193da8d |
3325 | return NULL; |
3326 | |
7c95608a |
3327 | i = e - g->edges; |
6193da8d |
3328 | |
3329 | /* I think it's only possible to play this game with mouse clicks, sorry */ |
3330 | /* Maybe will add mouse drag support some time */ |
7c95608a |
3331 | old_state = state->lines[i]; |
6193da8d |
3332 | |
3333 | switch (button) { |
7c95608a |
3334 | case LEFT_BUTTON: |
3335 | switch (old_state) { |
3336 | case LINE_UNKNOWN: |
3337 | button_char = 'y'; |
3338 | break; |
3339 | case LINE_YES: |
80e7e37c |
3340 | #ifdef STYLUS_BASED |
3341 | button_char = 'n'; |
3342 | break; |
3343 | #endif |
7c95608a |
3344 | case LINE_NO: |
3345 | button_char = 'u'; |
3346 | break; |
3347 | } |
3348 | break; |
3349 | case MIDDLE_BUTTON: |
3350 | button_char = 'u'; |
3351 | break; |
3352 | case RIGHT_BUTTON: |
3353 | switch (old_state) { |
3354 | case LINE_UNKNOWN: |
3355 | button_char = 'n'; |
3356 | break; |
3357 | case LINE_NO: |
80e7e37c |
3358 | #ifdef STYLUS_BASED |
3359 | button_char = 'y'; |
3360 | break; |
3361 | #endif |
7c95608a |
3362 | case LINE_YES: |
3363 | button_char = 'u'; |
3364 | break; |
3365 | } |
3366 | break; |
3367 | default: |
3368 | return NULL; |
3369 | } |
3370 | |
3371 | |
3372 | sprintf(buf, "%d%c", i, (int)button_char); |
6193da8d |
3373 | ret = dupstr(buf); |
3374 | |
3375 | return ret; |
3376 | } |
3377 | |
3378 | static game_state *execute_move(game_state *state, char *move) |
3379 | { |
7c95608a |
3380 | int i; |
6193da8d |
3381 | game_state *newstate = dup_game(state); |
3382 | |
3383 | if (move[0] == 'S') { |
3384 | move++; |
3385 | newstate->cheated = TRUE; |
3386 | } |
3387 | |
3388 | while (*move) { |
3389 | i = atoi(move); |
8719c2e7 |
3390 | if (i < 0 || i >= newstate->game_grid->num_edges) |
3391 | goto fail; |
6193da8d |
3392 | move += strspn(move, "1234567890"); |
3393 | switch (*(move++)) { |
7c95608a |
3394 | case 'y': |
3395 | newstate->lines[i] = LINE_YES; |
3396 | break; |
3397 | case 'n': |
3398 | newstate->lines[i] = LINE_NO; |
3399 | break; |
3400 | case 'u': |
3401 | newstate->lines[i] = LINE_UNKNOWN; |
3402 | break; |
3403 | default: |
3404 | goto fail; |
6193da8d |
3405 | } |
3406 | } |
3407 | |
3408 | /* |
3409 | * Check for completion. |
3410 | */ |
b6bf0adc |
3411 | if (check_completion(newstate)) |
121aae4b |
3412 | newstate->solved = TRUE; |
6193da8d |
3413 | |
6193da8d |
3414 | return newstate; |
3415 | |
7c95608a |
3416 | fail: |
6193da8d |
3417 | free_game(newstate); |
3418 | return NULL; |
3419 | } |
3420 | |
3421 | /* ---------------------------------------------------------------------- |
3422 | * Drawing routines. |
3423 | */ |
7c95608a |
3424 | |
3425 | /* Convert from grid coordinates to screen coordinates */ |
3426 | static void grid_to_screen(const game_drawstate *ds, const grid *g, |
3427 | int grid_x, int grid_y, int *x, int *y) |
3428 | { |
3429 | *x = grid_x - g->lowest_x; |
3430 | *y = grid_y - g->lowest_y; |
3431 | *x = *x * ds->tilesize / g->tilesize; |
3432 | *y = *y * ds->tilesize / g->tilesize; |
3433 | *x += BORDER(ds->tilesize); |
3434 | *y += BORDER(ds->tilesize); |
3435 | } |
3436 | |
3437 | /* Returns (into x,y) position of centre of face for rendering the text clue. |
3438 | */ |
3439 | static void face_text_pos(const game_drawstate *ds, const grid *g, |
e64991db |
3440 | grid_face *f, int *xret, int *yret) |
7c95608a |
3441 | { |
e0936bbd |
3442 | int faceindex = f - g->faces; |
7c95608a |
3443 | |
e0936bbd |
3444 | /* |
3445 | * Return the cached position for this face, if we've already |
3446 | * worked it out. |
3447 | */ |
3448 | if (ds->textx[faceindex] >= 0) { |
3449 | *xret = ds->textx[faceindex]; |
3450 | *yret = ds->texty[faceindex]; |
3451 | return; |
3452 | } |
7c95608a |
3453 | |
e0936bbd |
3454 | /* |
e64991db |
3455 | * Otherwise, use the incentre computed by grid.c and convert it |
3456 | * to screen coordinates. |
e0936bbd |
3457 | */ |
e64991db |
3458 | grid_find_incentre(f); |
3459 | grid_to_screen(ds, g, f->ix, f->iy, |
e0936bbd |
3460 | &ds->textx[faceindex], &ds->texty[faceindex]); |
3461 | |
3462 | *xret = ds->textx[faceindex]; |
3463 | *yret = ds->texty[faceindex]; |
7c95608a |
3464 | } |
3465 | |
1463f9f1 |
3466 | static void face_text_bbox(game_drawstate *ds, grid *g, grid_face *f, |
3467 | int *x, int *y, int *w, int *h) |
3468 | { |
3469 | int xx, yy; |
3470 | face_text_pos(ds, g, f, &xx, &yy); |
3471 | |
3472 | /* There seems to be a certain amount of trial-and-error involved |
3473 | * in working out the correct bounding-box for the text. */ |
3474 | |
3475 | *x = xx - ds->tilesize/4 - 1; |
3476 | *y = yy - ds->tilesize/4 - 3; |
3477 | *w = ds->tilesize/2 + 2; |
3478 | *h = ds->tilesize/2 + 5; |
3479 | } |
3480 | |
d68b2c10 |
3481 | static void game_redraw_clue(drawing *dr, game_drawstate *ds, |
3482 | game_state *state, int i) |
3483 | { |
3484 | grid *g = state->game_grid; |
3485 | grid_face *f = g->faces + i; |
3486 | int x, y; |
918a098a |
3487 | char c[3]; |
d68b2c10 |
3488 | |
918a098a |
3489 | if (state->clues[i] < 10) { |
3490 | c[0] = CLUE2CHAR(state->clues[i]); |
3491 | c[1] = '\0'; |
3492 | } else { |
3493 | sprintf(c, "%d", state->clues[i]); |
3494 | } |
d68b2c10 |
3495 | |
3496 | face_text_pos(ds, g, f, &x, &y); |
3497 | draw_text(dr, x, y, |
3498 | FONT_VARIABLE, ds->tilesize/2, |
3499 | ALIGN_VCENTRE | ALIGN_HCENTRE, |
3500 | ds->clue_error[i] ? COL_MISTAKE : |
3501 | ds->clue_satisfied[i] ? COL_SATISFIED : COL_FOREGROUND, c); |
3502 | } |
3503 | |
1463f9f1 |
3504 | static void edge_bbox(game_drawstate *ds, grid *g, grid_edge *e, |
3505 | int *x, int *y, int *w, int *h) |
3506 | { |
3507 | int x1 = e->dot1->x; |
3508 | int y1 = e->dot1->y; |
3509 | int x2 = e->dot2->x; |
3510 | int y2 = e->dot2->y; |
3511 | int xmin, xmax, ymin, ymax; |
3512 | |
3513 | grid_to_screen(ds, g, x1, y1, &x1, &y1); |
3514 | grid_to_screen(ds, g, x2, y2, &x2, &y2); |
3515 | /* Allow extra margin for dots, and thickness of lines */ |
3516 | xmin = min(x1, x2) - 2; |
3517 | xmax = max(x1, x2) + 2; |
3518 | ymin = min(y1, y2) - 2; |
3519 | ymax = max(y1, y2) + 2; |
3520 | |
3521 | *x = xmin; |
3522 | *y = ymin; |
3523 | *w = xmax - xmin + 1; |
3524 | *h = ymax - ymin + 1; |
3525 | } |
3526 | |
3527 | static void dot_bbox(game_drawstate *ds, grid *g, grid_dot *d, |
3528 | int *x, int *y, int *w, int *h) |
3529 | { |
3530 | int x1, y1; |
3531 | |
3532 | grid_to_screen(ds, g, d->x, d->y, &x1, &y1); |
3533 | |
3534 | *x = x1 - 2; |
3535 | *y = y1 - 2; |
3536 | *w = 5; |
3537 | *h = 5; |
3538 | } |
3539 | |
b0a2ee96 |
3540 | static const int loopy_line_redraw_phases[] = { |
3541 | COL_FAINT, COL_LINEUNKNOWN, COL_FOREGROUND, COL_HIGHLIGHT, COL_MISTAKE |
3542 | }; |
3543 | #define NPHASES lenof(loopy_line_redraw_phases) |
3544 | |
d68b2c10 |
3545 | static void game_redraw_line(drawing *dr, game_drawstate *ds, |
b0a2ee96 |
3546 | game_state *state, int i, int phase) |
d68b2c10 |
3547 | { |
3548 | grid *g = state->game_grid; |
3549 | grid_edge *e = g->edges + i; |
3550 | int x1, x2, y1, y2; |
d68b2c10 |
3551 | int line_colour; |
3552 | |
3553 | if (state->line_errors[i]) |
3554 | line_colour = COL_MISTAKE; |
3555 | else if (state->lines[i] == LINE_UNKNOWN) |
3556 | line_colour = COL_LINEUNKNOWN; |
3557 | else if (state->lines[i] == LINE_NO) |
3558 | line_colour = COL_FAINT; |
3559 | else if (ds->flashing) |
3560 | line_colour = COL_HIGHLIGHT; |
3561 | else |
3562 | line_colour = COL_FOREGROUND; |
b0a2ee96 |
3563 | if (line_colour != loopy_line_redraw_phases[phase]) |
3564 | return; |
d68b2c10 |
3565 | |
3566 | /* Convert from grid to screen coordinates */ |
3567 | grid_to_screen(ds, g, e->dot1->x, e->dot1->y, &x1, &y1); |
3568 | grid_to_screen(ds, g, e->dot2->x, e->dot2->y, &x2, &y2); |
3569 | |
d68b2c10 |
3570 | if (line_colour == COL_FAINT) { |
3571 | static int draw_faint_lines = -1; |
3572 | if (draw_faint_lines < 0) { |
3573 | char *env = getenv("LOOPY_FAINT_LINES"); |
3574 | draw_faint_lines = (!env || (env[0] == 'y' || |
3575 | env[0] == 'Y')); |
3576 | } |
3577 | if (draw_faint_lines) |
3578 | draw_line(dr, x1, y1, x2, y2, line_colour); |
3579 | } else { |
3580 | draw_thick_line(dr, 3.0, |
3581 | x1 + 0.5, y1 + 0.5, |
3582 | x2 + 0.5, y2 + 0.5, |
3583 | line_colour); |
3584 | } |
3585 | } |
3586 | |
3587 | static void game_redraw_dot(drawing *dr, game_drawstate *ds, |
3588 | game_state *state, int i) |
3589 | { |
3590 | grid *g = state->game_grid; |
3591 | grid_dot *d = g->dots + i; |
3592 | int x, y; |
3593 | |
3594 | grid_to_screen(ds, g, d->x, d->y, &x, &y); |
3595 | draw_circle(dr, x, y, 2, COL_FOREGROUND, COL_FOREGROUND); |
3596 | } |
3597 | |
1463f9f1 |
3598 | static int boxes_intersect(int x0, int y0, int w0, int h0, |
3599 | int x1, int y1, int w1, int h1) |
3600 | { |
3601 | /* |
3602 | * Two intervals intersect iff neither is wholly on one side of |
3603 | * the other. Two boxes intersect iff their horizontal and |
3604 | * vertical intervals both intersect. |
3605 | */ |
3606 | return (x0 < x1+w1 && x1 < x0+w0 && y0 < y1+h1 && y1 < y0+h0); |
3607 | } |
3608 | |
3609 | static void game_redraw_in_rect(drawing *dr, game_drawstate *ds, |
3610 | game_state *state, int x, int y, int w, int h) |
3611 | { |
3612 | grid *g = state->game_grid; |
3613 | int i, phase; |
3614 | int bx, by, bw, bh; |
3615 | |
3616 | clip(dr, x, y, w, h); |
3617 | draw_rect(dr, x, y, w, h, COL_BACKGROUND); |
3618 | |
3619 | for (i = 0; i < g->num_faces; i++) { |
75a52b16 |
3620 | if (state->clues[i] >= 0) { |
3621 | face_text_bbox(ds, g, &g->faces[i], &bx, &by, &bw, &bh); |
3622 | if (boxes_intersect(x, y, w, h, bx, by, bw, bh)) |
3623 | game_redraw_clue(dr, ds, state, i); |
3624 | } |
1463f9f1 |
3625 | } |
3626 | for (phase = 0; phase < NPHASES; phase++) { |
3627 | for (i = 0; i < g->num_edges; i++) { |
3628 | edge_bbox(ds, g, &g->edges[i], &bx, &by, &bw, &bh); |
3629 | if (boxes_intersect(x, y, w, h, bx, by, bw, bh)) |
3630 | game_redraw_line(dr, ds, state, i, phase); |
3631 | } |
3632 | } |
3633 | for (i = 0; i < g->num_dots; i++) { |
3634 | dot_bbox(ds, g, &g->dots[i], &bx, &by, &bw, &bh); |
3635 | if (boxes_intersect(x, y, w, h, bx, by, bw, bh)) |
3636 | game_redraw_dot(dr, ds, state, i); |
3637 | } |
3638 | |
3639 | unclip(dr); |
3640 | draw_update(dr, x, y, w, h); |
3641 | } |
3642 | |
6193da8d |
3643 | static void game_redraw(drawing *dr, game_drawstate *ds, game_state *oldstate, |
3644 | game_state *state, int dir, game_ui *ui, |
3645 | float animtime, float flashtime) |
3646 | { |
d68b2c10 |
3647 | #define REDRAW_OBJECTS_LIMIT 16 /* Somewhat arbitrary tradeoff */ |
3648 | |
7c95608a |
3649 | grid *g = state->game_grid; |
3650 | int border = BORDER(ds->tilesize); |
1463f9f1 |
3651 | int i; |
d68b2c10 |
3652 | int flash_changed; |
3653 | int redraw_everything = FALSE; |
3654 | |
3655 | int edges[REDRAW_OBJECTS_LIMIT], nedges = 0; |
3656 | int faces[REDRAW_OBJECTS_LIMIT], nfaces = 0; |
3657 | |
3658 | /* Redrawing is somewhat involved. |
3659 | * |
3660 | * An update can theoretically affect an arbitrary number of edges |
3661 | * (consider, for example, completing or breaking a cycle which doesn't |
3662 | * satisfy all the clues -- we'll switch many edges between error and |
3663 | * normal states). On the other hand, redrawing the whole grid takes a |
3664 | * while, making the game feel sluggish, and many updates are actually |
3665 | * quite well localized. |
3666 | * |
3667 | * This redraw algorithm attempts to cope with both situations gracefully |
3668 | * and correctly. For localized changes, we set a clip rectangle, fill |
3669 | * it with background, and then redraw (a plausible but conservative |
3670 | * guess at) the objects which intersect the rectangle; if several |
3671 | * objects need redrawing, we'll do them individually. However, if lots |
3672 | * of objects are affected, we'll just redraw everything. |
3673 | * |
3674 | * The reason for all of this is that it's just not safe to do the redraw |
3675 | * piecemeal. If you try to draw an antialiased diagonal line over |
3676 | * itself, you get a slightly thicker antialiased diagonal line, which |
3677 | * looks rather ugly after a while. |
3678 | * |
3679 | * So, we take two passes over the grid. The first attempts to work out |
3680 | * what needs doing, and the second actually does it. |
3681 | */ |
3682 | |
3683 | if (!ds->started) |
3684 | redraw_everything = TRUE; |
3685 | else { |
3686 | |
3687 | /* First, trundle through the faces. */ |
3688 | for (i = 0; i < g->num_faces; i++) { |
3689 | grid_face *f = g->faces + i; |
3690 | int sides = f->order; |
3691 | int clue_mistake; |
3692 | int clue_satisfied; |
3693 | int n = state->clues[i]; |
3694 | if (n < 0) |
3695 | continue; |
3696 | |
3697 | clue_mistake = (face_order(state, i, LINE_YES) > n || |
3698 | face_order(state, i, LINE_NO ) > (sides-n)); |
3699 | clue_satisfied = (face_order(state, i, LINE_YES) == n && |
3700 | face_order(state, i, LINE_NO ) == (sides-n)); |
3701 | |
3702 | if (clue_mistake != ds->clue_error[i] || |
3703 | clue_satisfied != ds->clue_satisfied[i]) { |
3704 | ds->clue_error[i] = clue_mistake; |
3705 | ds->clue_satisfied[i] = clue_satisfied; |
3706 | if (nfaces == REDRAW_OBJECTS_LIMIT) |
3707 | redraw_everything = TRUE; |
3708 | else |
3709 | faces[nfaces++] = i; |
3710 | } |
3711 | } |
3712 | |
3713 | /* Work out what the flash state needs to be. */ |
3714 | if (flashtime > 0 && |
3715 | (flashtime <= FLASH_TIME/3 || |
3716 | flashtime >= FLASH_TIME*2/3)) { |
3717 | flash_changed = !ds->flashing; |
3718 | ds->flashing = TRUE; |
3719 | } else { |
3720 | flash_changed = ds->flashing; |
3721 | ds->flashing = FALSE; |
3722 | } |
3723 | |
3724 | /* Now, trundle through the edges. */ |
3725 | for (i = 0; i < g->num_edges; i++) { |
3726 | char new_ds = |
3727 | state->line_errors[i] ? DS_LINE_ERROR : state->lines[i]; |
3728 | if (new_ds != ds->lines[i] || |
3729 | (flash_changed && state->lines[i] == LINE_YES)) { |
3730 | ds->lines[i] = new_ds; |
3731 | if (nedges == REDRAW_OBJECTS_LIMIT) |
3732 | redraw_everything = TRUE; |
3733 | else |
3734 | edges[nedges++] = i; |
3735 | } |
3736 | } |
3737 | } |
3738 | |
3739 | /* Pass one is now done. Now we do the actual drawing. */ |
3740 | if (redraw_everything) { |
7c95608a |
3741 | int grid_width = g->highest_x - g->lowest_x; |
3742 | int grid_height = g->highest_y - g->lowest_y; |
3743 | int w = grid_width * ds->tilesize / g->tilesize; |
3744 | int h = grid_height * ds->tilesize / g->tilesize; |
6193da8d |
3745 | |
1463f9f1 |
3746 | game_redraw_in_rect(dr, ds, state, |
3747 | 0, 0, w + 2*border + 1, h + 2*border + 1); |
d68b2c10 |
3748 | } else { |
c0eb17ce |
3749 | |
d68b2c10 |
3750 | /* Right. Now we roll up our sleeves. */ |
3751 | |
3752 | for (i = 0; i < nfaces; i++) { |
3753 | grid_face *f = g->faces + faces[i]; |
d68b2c10 |
3754 | int x, y, w, h; |
1463f9f1 |
3755 | |
3756 | face_text_bbox(ds, g, f, &x, &y, &w, &h); |
3757 | game_redraw_in_rect(dr, ds, state, x, y, w, h); |
d68b2c10 |
3758 | } |
c0eb17ce |
3759 | |
d68b2c10 |
3760 | for (i = 0; i < nedges; i++) { |
1463f9f1 |
3761 | grid_edge *e = g->edges + edges[i]; |
3762 | int x, y, w, h; |
6193da8d |
3763 | |
1463f9f1 |
3764 | edge_bbox(ds, g, e, &x, &y, &w, &h); |
3765 | game_redraw_in_rect(dr, ds, state, x, y, w, h); |
d68b2c10 |
3766 | } |
6193da8d |
3767 | } |
d68b2c10 |
3768 | |
7c95608a |
3769 | ds->started = TRUE; |
6193da8d |
3770 | } |
3771 | |
6193da8d |
3772 | static float game_flash_length(game_state *oldstate, game_state *newstate, |
3773 | int dir, game_ui *ui) |
3774 | { |
3775 | if (!oldstate->solved && newstate->solved && |
3776 | !oldstate->cheated && !newstate->cheated) { |
3777 | return FLASH_TIME; |
3778 | } |
3779 | |
3780 | return 0.0F; |
3781 | } |
3782 | |
4496362f |
3783 | static int game_is_solved(game_state *state) |
3784 | { |
3785 | return state->solved; |
3786 | } |
3787 | |
6193da8d |
3788 | static void game_print_size(game_params *params, float *x, float *y) |
3789 | { |
3790 | int pw, ph; |
3791 | |
3792 | /* |
7c95608a |
3793 | * I'll use 7mm "squares" by default. |
6193da8d |
3794 | */ |
3795 | game_compute_size(params, 700, &pw, &ph); |
3796 | *x = pw / 100.0F; |
3797 | *y = ph / 100.0F; |
3798 | } |
3799 | |
3800 | static void game_print(drawing *dr, game_state *state, int tilesize) |
3801 | { |
6193da8d |
3802 | int ink = print_mono_colour(dr, 0); |
7c95608a |
3803 | int i; |
6193da8d |
3804 | game_drawstate ads, *ds = &ads; |
7c95608a |
3805 | grid *g = state->game_grid; |
4413ef0f |
3806 | |
092e9395 |
3807 | ds->tilesize = tilesize; |
6193da8d |
3808 | |
7c95608a |
3809 | for (i = 0; i < g->num_dots; i++) { |
3810 | int x, y; |
3811 | grid_to_screen(ds, g, g->dots[i].x, g->dots[i].y, &x, &y); |
3812 | draw_circle(dr, x, y, ds->tilesize / 15, ink, ink); |
121aae4b |
3813 | } |
6193da8d |
3814 | |
3815 | /* |
3816 | * Clues. |
3817 | */ |
7c95608a |
3818 | for (i = 0; i < g->num_faces; i++) { |
3819 | grid_face *f = g->faces + i; |
3820 | int clue = state->clues[i]; |
3821 | if (clue >= 0) { |
121aae4b |
3822 | char c[2]; |
7c95608a |
3823 | int x, y; |
3824 | c[0] = CLUE2CHAR(clue); |
121aae4b |
3825 | c[1] = '\0'; |
7c95608a |
3826 | face_text_pos(ds, g, f, &x, &y); |
3827 | draw_text(dr, x, y, |
3828 | FONT_VARIABLE, ds->tilesize / 2, |
121aae4b |
3829 | ALIGN_VCENTRE | ALIGN_HCENTRE, ink, c); |
3830 | } |
3831 | } |
6193da8d |
3832 | |
3833 | /* |
7c95608a |
3834 | * Lines. |
6193da8d |
3835 | */ |
7c95608a |
3836 | for (i = 0; i < g->num_edges; i++) { |
3837 | int thickness = (state->lines[i] == LINE_YES) ? 30 : 150; |
3838 | grid_edge *e = g->edges + i; |
3839 | int x1, y1, x2, y2; |
3840 | grid_to_screen(ds, g, e->dot1->x, e->dot1->y, &x1, &y1); |
3841 | grid_to_screen(ds, g, e->dot2->x, e->dot2->y, &x2, &y2); |
3842 | if (state->lines[i] == LINE_YES) |
3843 | { |
3844 | /* (dx, dy) points from (x1, y1) to (x2, y2). |
3845 | * The line is then "fattened" in a perpendicular |
3846 | * direction to create a thin rectangle. */ |
3847 | double d = sqrt(SQ((double)x1 - x2) + SQ((double)y1 - y2)); |
3848 | double dx = (x2 - x1) / d; |
3849 | double dy = (y2 - y1) / d; |
1515b973 |
3850 | int points[8]; |
3851 | |
7c95608a |
3852 | dx = (dx * ds->tilesize) / thickness; |
3853 | dy = (dy * ds->tilesize) / thickness; |
b1535c90 |
3854 | points[0] = x1 + (int)dy; |
3855 | points[1] = y1 - (int)dx; |
3856 | points[2] = x1 - (int)dy; |
3857 | points[3] = y1 + (int)dx; |
3858 | points[4] = x2 - (int)dy; |
3859 | points[5] = y2 + (int)dx; |
3860 | points[6] = x2 + (int)dy; |
3861 | points[7] = y2 - (int)dx; |
7c95608a |
3862 | draw_polygon(dr, points, 4, ink, ink); |
3863 | } |
3864 | else |
3865 | { |
3866 | /* Draw a dotted line */ |
3867 | int divisions = 6; |
3868 | int j; |
3869 | for (j = 1; j < divisions; j++) { |
3870 | /* Weighted average */ |
3871 | int x = (x1 * (divisions -j) + x2 * j) / divisions; |
3872 | int y = (y1 * (divisions -j) + y2 * j) / divisions; |
3873 | draw_circle(dr, x, y, ds->tilesize / thickness, ink, ink); |
3874 | } |
3875 | } |
121aae4b |
3876 | } |
6193da8d |
3877 | } |
3878 | |
3879 | #ifdef COMBINED |
3880 | #define thegame loopy |
3881 | #endif |
3882 | |
3883 | const struct game thegame = { |
750037d7 |
3884 | "Loopy", "games.loopy", "loopy", |
6193da8d |
3885 | default_params, |
3886 | game_fetch_preset, |
3887 | decode_params, |
3888 | encode_params, |
3889 | free_params, |
3890 | dup_params, |
3891 | TRUE, game_configure, custom_params, |
3892 | validate_params, |
3893 | new_game_desc, |
3894 | validate_desc, |
3895 | new_game, |
3896 | dup_game, |
3897 | free_game, |
3898 | 1, solve_game, |
fa3abef5 |
3899 | TRUE, game_can_format_as_text_now, game_text_format, |
6193da8d |
3900 | new_ui, |
3901 | free_ui, |
3902 | encode_ui, |
3903 | decode_ui, |
3904 | game_changed_state, |
3905 | interpret_move, |
3906 | execute_move, |
3907 | PREFERRED_TILE_SIZE, game_compute_size, game_set_size, |
3908 | game_colours, |
3909 | game_new_drawstate, |
3910 | game_free_drawstate, |
3911 | game_redraw, |
3912 | game_anim_length, |
3913 | game_flash_length, |
4496362f |
3914 | game_is_solved, |
6193da8d |
3915 | TRUE, FALSE, game_print_size, game_print, |
121aae4b |
3916 | FALSE /* wants_statusbar */, |
6193da8d |
3917 | FALSE, game_timing_state, |
121aae4b |
3918 | 0, /* mouse_priorities */ |
6193da8d |
3919 | }; |
5ca89681 |
3920 | |
3921 | #ifdef STANDALONE_SOLVER |
3922 | |
3923 | /* |
3924 | * Half-hearted standalone solver. It can't output the solution to |
3925 | * anything but a square puzzle, and it can't log the deductions |
3926 | * it makes either. But it can solve square puzzles, and more |
3927 | * importantly it can use its solver to grade the difficulty of |
3928 | * any puzzle you give it. |
3929 | */ |
3930 | |
3931 | #include <stdarg.h> |
3932 | |
3933 | int main(int argc, char **argv) |
3934 | { |
3935 | game_params *p; |
3936 | game_state *s; |
3937 | char *id = NULL, *desc, *err; |
3938 | int grade = FALSE; |
3939 | int ret, diff; |
3940 | #if 0 /* verbose solver not supported here (yet) */ |
3941 | int really_verbose = FALSE; |
3942 | #endif |
3943 | |
3944 | while (--argc > 0) { |
3945 | char *p = *++argv; |
3946 | #if 0 /* verbose solver not supported here (yet) */ |
3947 | if (!strcmp(p, "-v")) { |
3948 | really_verbose = TRUE; |
3949 | } else |
3950 | #endif |
3951 | if (!strcmp(p, "-g")) { |
3952 | grade = TRUE; |
3953 | } else if (*p == '-') { |
3954 | fprintf(stderr, "%s: unrecognised option `%s'\n", argv[0], p); |
3955 | return 1; |
3956 | } else { |
3957 | id = p; |
3958 | } |
3959 | } |
3960 | |
3961 | if (!id) { |
3962 | fprintf(stderr, "usage: %s [-g | -v] <game_id>\n", argv[0]); |
3963 | return 1; |
3964 | } |
3965 | |
3966 | desc = strchr(id, ':'); |
3967 | if (!desc) { |
3968 | fprintf(stderr, "%s: game id expects a colon in it\n", argv[0]); |
3969 | return 1; |
3970 | } |
3971 | *desc++ = '\0'; |
3972 | |
3973 | p = default_params(); |
3974 | decode_params(p, id); |
3975 | err = validate_desc(p, desc); |
3976 | if (err) { |
3977 | fprintf(stderr, "%s: %s\n", argv[0], err); |
3978 | return 1; |
3979 | } |
3980 | s = new_game(NULL, p, desc); |
3981 | |
3982 | /* |
3983 | * When solving an Easy puzzle, we don't want to bother the |
3984 | * user with Hard-level deductions. For this reason, we grade |
3985 | * the puzzle internally before doing anything else. |
3986 | */ |
3987 | ret = -1; /* placate optimiser */ |
3988 | for (diff = 0; diff < DIFF_MAX; diff++) { |
3989 | solver_state *sstate_new; |
3990 | solver_state *sstate = new_solver_state((game_state *)s, diff); |
3991 | |
315e47b9 |
3992 | sstate_new = solve_game_rec(sstate); |
5ca89681 |
3993 | |
3994 | if (sstate_new->solver_status == SOLVER_MISTAKE) |
3995 | ret = 0; |
3996 | else if (sstate_new->solver_status == SOLVER_SOLVED) |
3997 | ret = 1; |
3998 | else |
3999 | ret = 2; |
4000 | |
4001 | free_solver_state(sstate_new); |
4002 | free_solver_state(sstate); |
4003 | |
4004 | if (ret < 2) |
4005 | break; |
4006 | } |
4007 | |
4008 | if (diff == DIFF_MAX) { |
4009 | if (grade) |
4010 | printf("Difficulty rating: harder than Hard, or ambiguous\n"); |
4011 | else |
4012 | printf("Unable to find a unique solution\n"); |
4013 | } else { |
4014 | if (grade) { |
4015 | if (ret == 0) |
4016 | printf("Difficulty rating: impossible (no solution exists)\n"); |
4017 | else if (ret == 1) |
4018 | printf("Difficulty rating: %s\n", diffnames[diff]); |
4019 | } else { |
4020 | solver_state *sstate_new; |
4021 | solver_state *sstate = new_solver_state((game_state *)s, diff); |
4022 | |
4023 | /* If we supported a verbose solver, we'd set verbosity here */ |
4024 | |
315e47b9 |
4025 | sstate_new = solve_game_rec(sstate); |
5ca89681 |
4026 | |
4027 | if (sstate_new->solver_status == SOLVER_MISTAKE) |
4028 | printf("Puzzle is inconsistent\n"); |
4029 | else { |
4030 | assert(sstate_new->solver_status == SOLVER_SOLVED); |
4031 | if (s->grid_type == 0) { |
4032 | fputs(game_text_format(sstate_new->state), stdout); |
4033 | } else { |
4034 | printf("Unable to output non-square grids\n"); |
4035 | } |
4036 | } |
4037 | |
4038 | free_solver_state(sstate_new); |
4039 | free_solver_state(sstate); |
4040 | } |
4041 | } |
4042 | |
4043 | return 0; |
4044 | } |
4045 | |
4046 | #endif |
cebf0b0d |
4047 | |
4048 | /* vim: set shiftwidth=4 tabstop=8: */ |