X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?a=blobdiff_plain;f=loopy.c;h=92b27ab51690f10aa89983b8af934fa591dc1449;hb=db313b3948d27244dd7c34c2609c66d6204d8931;hp=6d88e5dbcd4350d332dd1c6bc895f79df90e0af9;hpb=5d503a52db029434cd354e04a0c6adbd2081fefa;p=sgt-puzzles.git diff --git a/loopy.c b/loopy.c index 6d88e5d..92b27ab 100644 --- a/loopy.c +++ b/loopy.c @@ -82,6 +82,7 @@ #include "puzzles.h" #include "tree234.h" #include "grid.h" +#include "loopgen.h" /* Debugging options */ @@ -107,7 +108,7 @@ enum { }; struct game_state { - grid *game_grid; + grid *game_grid; /* ref-counted (internally) */ /* Put -1 in a face that doesn't get a clue */ signed char *clues; @@ -117,6 +118,7 @@ struct game_state { char *lines; unsigned char *line_errors; + int exactly_one_loop; int solved; int cheated; @@ -201,16 +203,12 @@ static char const diffchars[] = DIFFLIST(ENCODE); SOLVERLIST(SOLVER_FN_DECL) static int (*(solver_fns[]))(solver_state *) = { SOLVERLIST(SOLVER_FN) }; static int const solver_diffs[] = { SOLVERLIST(SOLVER_DIFF) }; -const int NUM_SOLVERS = sizeof(solver_diffs)/sizeof(*solver_diffs); +static const int NUM_SOLVERS = sizeof(solver_diffs)/sizeof(*solver_diffs); struct game_params { int w, h; int diff; int type; - - /* Grid generation is expensive, so keep a (ref-counted) reference to the - * grid for these parameters, and only generate when required. */ - grid *game_grid; }; /* line_drawstate is the same as line_state, but with the extra ERROR @@ -234,7 +232,7 @@ struct game_drawstate { char *clue_satisfied; }; -static char *validate_desc(game_params *params, char *desc); +static char *validate_desc(const game_params *params, const char *desc); static int dot_order(const game_state* state, int i, char line_type); static int face_order(const game_state* state, int i, char line_type); static solver_state *solve_game_rec(const solver_state *sstate); @@ -245,31 +243,56 @@ static void check_caches(const solver_state* sstate); #define check_caches(s) #endif -/* ------- List of grid generators ------- */ -#define GRIDLIST(A) \ - A(Squares,grid_new_square,3,3) \ - A(Triangular,grid_new_triangular,3,3) \ - A(Honeycomb,grid_new_honeycomb,3,3) \ - A(Snub-Square,grid_new_snubsquare,3,3) \ - A(Cairo,grid_new_cairo,3,4) \ - A(Great-Hexagonal,grid_new_greathexagonal,3,3) \ - A(Octagonal,grid_new_octagonal,3,3) \ - A(Kites,grid_new_kites,3,3) \ - A(Floret,grid_new_floret,1,2) \ - A(Dodecagonal,grid_new_dodecagonal,2,2) \ - A(Great-Dodecagonal,grid_new_greatdodecagonal,2,2) - -#define GRID_NAME(title,fn,amin,omin) #title, -#define GRID_CONFIG(title,fn,amin,omin) ":" #title -#define GRID_FN(title,fn,amin,omin) &fn, -#define GRID_SIZES(title,fn,amin,omin) \ +/* + * Grid type config options available in Loopy. + * + * Annoyingly, we have to use an enum here which doesn't match up + * exactly to the grid-type enum in grid.h. Values in params->types + * are given by names such as LOOPY_GRID_SQUARE, which shouldn't be + * confused with GRID_SQUARE which is the value you pass to grid_new() + * and friends. So beware! + * + * (This is partly for historical reasons - Loopy's version of the + * enum is encoded in game parameter strings, so we keep it for + * backwards compatibility. But also, we need to store additional data + * here alongside each enum value, such as names for the presets menu, + * which isn't stored in grid.h; so we have to have our own list macro + * here anyway, and C doesn't make it easy to enforce that that lines + * up exactly with grid.h.) + * + * Do not add values to this list _except_ at the end, or old game ids + * will stop working! + */ +#define GRIDLIST(A) \ + A("Squares",SQUARE,3,3) \ + A("Triangular",TRIANGULAR,3,3) \ + A("Honeycomb",HONEYCOMB,3,3) \ + A("Snub-Square",SNUBSQUARE,3,3) \ + A("Cairo",CAIRO,3,4) \ + A("Great-Hexagonal",GREATHEXAGONAL,3,3) \ + A("Octagonal",OCTAGONAL,3,3) \ + A("Kites",KITE,3,3) \ + A("Floret",FLORET,1,2) \ + A("Dodecagonal",DODECAGONAL,2,2) \ + A("Great-Dodecagonal",GREATDODECAGONAL,2,2) \ + A("Penrose (kite/dart)",PENROSE_P2,3,3) \ + A("Penrose (rhombs)",PENROSE_P3,3,3) \ + A("Great-Great-Dodecagonal",GREATGREATDODECAGONAL,2,2) \ + /* end of list */ + +#define GRID_NAME(title,type,amin,omin) title, +#define GRID_CONFIG(title,type,amin,omin) ":" title +#define GRID_LOOPYTYPE(title,type,amin,omin) LOOPY_GRID_ ## type, +#define GRID_GRIDTYPE(title,type,amin,omin) GRID_ ## type, +#define GRID_SIZES(title,type,amin,omin) \ {amin, omin, \ "Width and height for this grid type must both be at least " #amin, \ "At least one of width and height for this grid type must be at least " #omin,}, +enum { GRIDLIST(GRID_LOOPYTYPE) LOOPY_GRID_DUMMY_TERMINATOR }; static char const *const gridnames[] = { GRIDLIST(GRID_NAME) }; #define GRID_CONFIGS GRIDLIST(GRID_CONFIG) -static grid * (*(grid_fns[]))(int w, int h) = { GRIDLIST(GRID_FN) }; -#define NUM_GRID_TYPES (sizeof(grid_fns) / sizeof(grid_fns[0])) +static grid_type grid_types[] = { GRIDLIST(GRID_GRIDTYPE) }; +#define NUM_GRID_TYPES (sizeof(grid_types) / sizeof(grid_types[0])) static const struct { int amin, omin; char *aerr, *oerr; @@ -277,13 +300,11 @@ static const struct { /* Generates a (dynamically allocated) new grid, according to the * type and size requested in params. Does nothing if the grid is already - * generated. The allocated grid is owned by the params object, and will be - * freed in free_params(). */ -static void params_generate_grid(game_params *params) + * generated. */ +static grid *loopy_generate_grid(const game_params *params, + const char *grid_desc) { - if (!params->game_grid) { - params->game_grid = grid_fns[params->type](params->w, params->h); - } + return grid_new(grid_types[params->type], params->w, params->h, grid_desc); } /* ---------------------------------------------------------------------- @@ -310,7 +331,7 @@ static void params_generate_grid(game_params *params) * General struct manipulation and other straightforward code */ -static game_state *dup_game(game_state *state) +static game_state *dup_game(const game_state *state) { game_state *ret = snew(game_state); @@ -328,6 +349,7 @@ static game_state *dup_game(game_state *state) ret->line_errors = snewn(state->game_grid->num_edges, unsigned char); memcpy(ret->line_errors, state->line_errors, state->game_grid->num_edges); + ret->exactly_one_loop = state->exactly_one_loop; ret->grid_type = state->grid_type; return ret; @@ -344,7 +366,7 @@ static void free_game(game_state *state) } } -static solver_state *new_solver_state(game_state *state, int diff) { +static solver_state *new_solver_state(const game_state *state, int diff) { int i; int num_dots = state->game_grid->num_dots; int num_faces = state->game_grid->num_faces; @@ -480,89 +502,102 @@ static game_params *default_params(void) ret->diff = DIFF_EASY; ret->type = 0; - ret->game_grid = NULL; - return ret; } -static game_params *dup_params(game_params *params) +static game_params *dup_params(const game_params *params) { game_params *ret = snew(game_params); *ret = *params; /* structure copy */ - if (ret->game_grid) { - ret->game_grid->refcount++; - } return ret; } -static const game_params presets[] = { +static const game_params loopy_presets_top[] = { #ifdef SMALL_SCREEN - { 7, 7, DIFF_EASY, 0, NULL }, - { 7, 7, DIFF_NORMAL, 0, NULL }, - { 7, 7, DIFF_HARD, 0, NULL }, - { 7, 7, DIFF_HARD, 1, NULL }, - { 7, 7, DIFF_HARD, 2, NULL }, - { 5, 5, DIFF_HARD, 3, NULL }, - { 7, 7, DIFF_HARD, 4, NULL }, - { 5, 4, DIFF_HARD, 5, NULL }, - { 5, 5, DIFF_HARD, 6, NULL }, - { 5, 5, DIFF_HARD, 7, NULL }, - { 3, 3, DIFF_HARD, 8, NULL }, - { 3, 3, DIFF_HARD, 9, NULL }, - { 3, 3, DIFF_HARD, 10, NULL }, + { 7, 7, DIFF_EASY, LOOPY_GRID_SQUARE }, + { 7, 7, DIFF_NORMAL, LOOPY_GRID_SQUARE }, + { 7, 7, DIFF_HARD, LOOPY_GRID_SQUARE }, + { 7, 7, DIFF_HARD, LOOPY_GRID_TRIANGULAR }, + { 5, 5, DIFF_HARD, LOOPY_GRID_SNUBSQUARE }, + { 7, 7, DIFF_HARD, LOOPY_GRID_CAIRO }, + { 5, 5, DIFF_HARD, LOOPY_GRID_KITE }, + { 6, 6, DIFF_HARD, LOOPY_GRID_PENROSE_P2 }, + { 6, 6, DIFF_HARD, LOOPY_GRID_PENROSE_P3 }, #else - { 7, 7, DIFF_EASY, 0, NULL }, - { 10, 10, DIFF_EASY, 0, NULL }, - { 7, 7, DIFF_NORMAL, 0, NULL }, - { 10, 10, DIFF_NORMAL, 0, NULL }, - { 7, 7, DIFF_HARD, 0, NULL }, - { 10, 10, DIFF_HARD, 0, NULL }, - { 10, 10, DIFF_HARD, 1, NULL }, - { 12, 10, DIFF_HARD, 2, NULL }, - { 7, 7, DIFF_HARD, 3, NULL }, - { 9, 9, DIFF_HARD, 4, NULL }, - { 5, 4, DIFF_HARD, 5, NULL }, - { 7, 7, DIFF_HARD, 6, NULL }, - { 5, 5, DIFF_HARD, 7, NULL }, - { 5, 5, DIFF_HARD, 8, NULL }, - { 5, 4, DIFF_HARD, 9, NULL }, - { 5, 4, DIFF_HARD, 10, NULL }, + { 7, 7, DIFF_EASY, LOOPY_GRID_SQUARE }, + { 10, 10, DIFF_EASY, LOOPY_GRID_SQUARE }, + { 7, 7, DIFF_NORMAL, LOOPY_GRID_SQUARE }, + { 10, 10, DIFF_NORMAL, LOOPY_GRID_SQUARE }, + { 7, 7, DIFF_HARD, LOOPY_GRID_SQUARE }, + { 10, 10, DIFF_HARD, LOOPY_GRID_SQUARE }, + { 12, 10, DIFF_HARD, LOOPY_GRID_TRIANGULAR }, + { 7, 7, DIFF_HARD, LOOPY_GRID_SNUBSQUARE }, + { 9, 9, DIFF_HARD, LOOPY_GRID_CAIRO }, + { 5, 5, DIFF_HARD, LOOPY_GRID_KITE }, + { 10, 10, DIFF_HARD, LOOPY_GRID_PENROSE_P2 }, + { 10, 10, DIFF_HARD, LOOPY_GRID_PENROSE_P3 }, #endif }; -static int game_fetch_preset(int i, char **name, game_params **params) +static const game_params loopy_presets_more[] = { +#ifdef SMALL_SCREEN + { 7, 7, DIFF_HARD, LOOPY_GRID_HONEYCOMB }, + { 5, 4, DIFF_HARD, LOOPY_GRID_GREATHEXAGONAL }, + { 5, 5, DIFF_HARD, LOOPY_GRID_OCTAGONAL }, + { 3, 3, DIFF_HARD, LOOPY_GRID_FLORET }, + { 3, 3, DIFF_HARD, LOOPY_GRID_DODECAGONAL }, + { 3, 3, DIFF_HARD, LOOPY_GRID_GREATDODECAGONAL }, + { 3, 2, DIFF_HARD, LOOPY_GRID_GREATGREATDODECAGONAL }, +#else + { 10, 10, DIFF_HARD, LOOPY_GRID_HONEYCOMB }, + { 5, 4, DIFF_HARD, LOOPY_GRID_GREATHEXAGONAL }, + { 7, 7, DIFF_HARD, LOOPY_GRID_OCTAGONAL }, + { 5, 5, DIFF_HARD, LOOPY_GRID_FLORET }, + { 5, 4, DIFF_HARD, LOOPY_GRID_DODECAGONAL }, + { 5, 4, DIFF_HARD, LOOPY_GRID_GREATDODECAGONAL }, + { 5, 3, DIFF_HARD, LOOPY_GRID_GREATGREATDODECAGONAL }, +#endif +}; + +static void preset_menu_add_preset_with_title(struct preset_menu *menu, + const game_params *params) { - game_params *tmppar; char buf[80]; + game_params *dup_params; - if (i < 0 || i >= lenof(presets)) - return FALSE; + sprintf(buf, "%dx%d %s - %s", params->h, params->w, + gridnames[params->type], diffnames[params->diff]); - tmppar = snew(game_params); - *tmppar = presets[i]; - *params = tmppar; - sprintf(buf, "%dx%d %s - %s", tmppar->h, tmppar->w, - gridnames[tmppar->type], diffnames[tmppar->diff]); - *name = dupstr(buf); + dup_params = snew(game_params); + *dup_params = *params; - return TRUE; + preset_menu_add_preset(menu, dupstr(buf), dup_params); +} + +static struct preset_menu *game_preset_menu(void) +{ + struct preset_menu *top, *more; + int i; + + top = preset_menu_new(); + for (i = 0; i < lenof(loopy_presets_top); i++) + preset_menu_add_preset_with_title(top, &loopy_presets_top[i]); + + more = preset_menu_add_submenu(top, dupstr("More...")); + for (i = 0; i < lenof(loopy_presets_more); i++) + preset_menu_add_preset_with_title(more, &loopy_presets_more[i]); + + return top; } static void free_params(game_params *params) { - if (params->game_grid) { - grid_free(params->game_grid); - } sfree(params); } static void decode_params(game_params *params, char const *string) { - if (params->game_grid) { - grid_free(params->game_grid); - params->game_grid = NULL; - } params->h = params->w = atoi(string); params->diff = DIFF_EASY; while (*string && isdigit((unsigned char)*string)) string++; @@ -586,7 +621,7 @@ static void decode_params(game_params *params, char const *string) } } -static char *encode_params(game_params *params, int full) +static char *encode_params(const game_params *params, int full) { char str[80]; sprintf(str, "%dx%dt%d", params->w, params->h, params->type); @@ -595,7 +630,7 @@ static char *encode_params(game_params *params, int full) return dupstr(str); } -static config_item *game_configure(game_params *params) +static config_item *game_configure(const game_params *params) { config_item *ret; char buf[80]; @@ -632,7 +667,7 @@ static config_item *game_configure(game_params *params) return ret; } -static game_params *custom_params(config_item *cfg) +static game_params *custom_params(const config_item *cfg) { game_params *ret = snew(game_params); @@ -641,11 +676,10 @@ static game_params *custom_params(config_item *cfg) ret->type = cfg[2].ival; ret->diff = cfg[3].ival; - ret->game_grid = NULL; return ret; } -static char *validate_params(game_params *params, int full) +static char *validate_params(const game_params *params, int full) { if (params->type < 0 || params->type >= NUM_GRID_TYPES) return "Illegal grid type"; @@ -702,14 +736,44 @@ static char *state_to_text(const game_state *state) return retval; } +#define GRID_DESC_SEP '_' + +/* Splits up a (optional) grid_desc from the game desc. Returns the + * grid_desc (which needs freeing) and updates the desc pointer to + * start of real desc, or returns NULL if no desc. */ +static char *extract_grid_desc(const char **desc) +{ + char *sep = strchr(*desc, GRID_DESC_SEP), *gd; + int gd_len; + + if (!sep) return NULL; + + gd_len = sep - (*desc); + gd = snewn(gd_len+1, char); + memcpy(gd, *desc, gd_len); + gd[gd_len] = '\0'; + + *desc = sep+1; + + return gd; +} + /* We require that the params pass the test in validate_params and that the * description fills the entire game area */ -static char *validate_desc(game_params *params, char *desc) +static char *validate_desc(const game_params *params, const char *desc) { int count = 0; grid *g; - params_generate_grid(params); - g = params->game_grid; + char *grid_desc, *ret; + + /* It's pretty inefficient to do this just for validation. All we need to + * know is the precise number of faces. */ + grid_desc = extract_grid_desc(&desc); + ret = grid_validate_desc(grid_types[params->type], params->w, params->h, grid_desc); + if (ret) return ret; + + g = loopy_generate_grid(params, grid_desc); + if (grid_desc) sfree(grid_desc); for (; *desc; ++desc) { if ((*desc >= '0' && *desc <= '9') || (*desc >= 'A' && *desc <= 'Z')) { @@ -728,6 +792,8 @@ static char *validate_desc(game_params *params, char *desc) if (count > g->num_faces) return "Description too long for board size"; + grid_free(g); + return NULL; } @@ -783,7 +849,7 @@ static char *encode_solve_move(const game_state *state) return ret; } -static game_ui *new_ui(game_state *state) +static game_ui *new_ui(const game_state *state) { return NULL; } @@ -792,46 +858,45 @@ static void free_ui(game_ui *ui) { } -static char *encode_ui(game_ui *ui) +static char *encode_ui(const game_ui *ui) { return NULL; } -static void decode_ui(game_ui *ui, char *encoding) +static void decode_ui(game_ui *ui, const char *encoding) { } -static void game_changed_state(game_ui *ui, game_state *oldstate, - game_state *newstate) +static void game_changed_state(game_ui *ui, const game_state *oldstate, + const game_state *newstate) { } -static void game_compute_size(game_params *params, int tilesize, +static void game_compute_size(const game_params *params, int tilesize, int *x, int *y) { - grid *g; int grid_width, grid_height, rendered_width, rendered_height; + int g_tilesize; + + grid_compute_size(grid_types[params->type], params->w, params->h, + &g_tilesize, &grid_width, &grid_height); - params_generate_grid(params); - g = params->game_grid; - grid_width = g->highest_x - g->lowest_x; - grid_height = g->highest_y - g->lowest_y; /* multiply first to minimise rounding error on integer division */ - rendered_width = grid_width * tilesize / g->tilesize; - rendered_height = grid_height * tilesize / g->tilesize; + rendered_width = grid_width * tilesize / g_tilesize; + rendered_height = grid_height * tilesize / g_tilesize; *x = rendered_width + 2 * BORDER(tilesize) + 1; *y = rendered_height + 2 * BORDER(tilesize) + 1; } static void game_set_size(drawing *dr, game_drawstate *ds, - game_params *params, int tilesize) + const game_params *params, int tilesize) { ds->tilesize = tilesize; } static float *game_colours(frontend *fe, int *ncolours) { - float *ret = snewn(4 * NCOLOURS, float); + float *ret = snewn(3 * NCOLOURS, float); frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]); @@ -873,7 +938,7 @@ static float *game_colours(frontend *fe, int *ncolours) return ret; } -static game_drawstate *game_new_drawstate(drawing *dr, game_state *state) +static game_drawstate *game_new_drawstate(drawing *dr, const game_state *state) { struct game_drawstate *ds = snew(struct game_drawstate); int num_faces = state->game_grid->num_faces; @@ -900,31 +965,33 @@ static game_drawstate *game_new_drawstate(drawing *dr, game_state *state) static void game_free_drawstate(drawing *dr, game_drawstate *ds) { + sfree(ds->textx); + sfree(ds->texty); sfree(ds->clue_error); sfree(ds->clue_satisfied); sfree(ds->lines); sfree(ds); } -static int game_timing_state(game_state *state, game_ui *ui) +static int game_timing_state(const game_state *state, game_ui *ui) { return TRUE; } -static float game_anim_length(game_state *oldstate, game_state *newstate, - int dir, game_ui *ui) +static float game_anim_length(const game_state *oldstate, + const game_state *newstate, int dir, game_ui *ui) { return 0.0F; } -static int game_can_format_as_text_now(game_params *params) +static int game_can_format_as_text_now(const game_params *params) { if (params->type != 0) return FALSE; return TRUE; } -static char *game_text_format(game_state *state) +static char *game_text_format(const game_state *state) { int w, h, W, H; int x, y, i; @@ -1258,507 +1325,20 @@ static int face_setall(solver_state *sstate, int face, * Loop generation and clue removal */ -/* We're going to store lists of current candidate faces for colouring black - * or white. - * Each face gets a 'score', which tells us how adding that face right - * now would affect the curliness of the solution loop. We're trying to - * maximise that quantity so will bias our random selection of faces to - * colour those with high scores */ -struct face_score { - int white_score; - int black_score; - unsigned long random; - /* No need to store a grid_face* here. The 'face_scores' array will - * be a list of 'face_score' objects, one for each face of the grid, so - * the position (index) within the 'face_scores' array will determine - * which face corresponds to a particular face_score. - * Having a single 'face_scores' array for all faces simplifies memory - * management, and probably improves performance, because we don't have to - * malloc/free each individual face_score, and we don't have to maintain - * a mapping from grid_face* pointers to face_score* pointers. - */ -}; - -static int generic_sort_cmpfn(void *v1, void *v2, size_t offset) -{ - struct face_score *f1 = v1; - struct face_score *f2 = v2; - int r; - - r = *(int *)((char *)f2 + offset) - *(int *)((char *)f1 + offset); - if (r) { - return r; - } - - if (f1->random < f2->random) - return -1; - else if (f1->random > f2->random) - return 1; - - /* - * It's _just_ possible that two faces might have been given - * the same random value. In that situation, fall back to - * comparing based on the positions within the face_scores list. - * This introduces a tiny directional bias, but not a significant one. - */ - return f1 - f2; -} - -static int white_sort_cmpfn(void *v1, void *v2) -{ - return generic_sort_cmpfn(v1, v2, offsetof(struct face_score,white_score)); -} - -static int black_sort_cmpfn(void *v1, void *v2) -{ - return generic_sort_cmpfn(v1, v2, offsetof(struct face_score,black_score)); -} - -enum face_colour { FACE_WHITE, FACE_GREY, FACE_BLACK }; - -/* face should be of type grid_face* here. */ -#define FACE_COLOUR(face) \ - ( (face) == NULL ? FACE_BLACK : \ - board[(face) - g->faces] ) - -/* 'board' is an array of these enums, indicating which faces are - * currently black/white/grey. 'colour' is FACE_WHITE or FACE_BLACK. - * Returns whether it's legal to colour the given face with this colour. */ -static int can_colour_face(grid *g, char* board, int face_index, - enum face_colour colour) -{ - int i, j; - grid_face *test_face = g->faces + face_index; - grid_face *starting_face, *current_face; - grid_dot *starting_dot; - int transitions; - int current_state, s; /* booleans: equal or not-equal to 'colour' */ - int found_same_coloured_neighbour = FALSE; - assert(board[face_index] != colour); - - /* Can only consider a face for colouring if it's adjacent to a face - * with the same colour. */ - for (i = 0; i < test_face->order; i++) { - grid_edge *e = test_face->edges[i]; - grid_face *f = (e->face1 == test_face) ? e->face2 : e->face1; - if (FACE_COLOUR(f) == colour) { - found_same_coloured_neighbour = TRUE; - break; - } - } - if (!found_same_coloured_neighbour) - return FALSE; - - /* Need to avoid creating a loop of faces of this colour around some - * differently-coloured faces. - * Also need to avoid meeting a same-coloured face at a corner, with - * other-coloured faces in between. Here's a simple test that (I believe) - * takes care of both these conditions: - * - * Take the circular path formed by this face's edges, and inflate it - * slightly outwards. Imagine walking around this path and consider - * the faces that you visit in sequence. This will include all faces - * touching the given face, either along an edge or just at a corner. - * Count the number of 'colour'/not-'colour' transitions you encounter, as - * you walk along the complete loop. This will obviously turn out to be - * an even number. - * If 0, we're either in the middle of an "island" of this colour (should - * be impossible as we're not supposed to create black or white loops), - * or we're about to start a new island - also not allowed. - * If 4 or greater, there are too many separate coloured regions touching - * this face, and colouring it would create a loop or a corner-violation. - * The only allowed case is when the count is exactly 2. */ - - /* i points to a dot around the test face. - * j points to a face around the i^th dot. - * The current face will always be: - * test_face->dots[i]->faces[j] - * We assume dots go clockwise around the test face, - * and faces go clockwise around dots. */ - - /* - * The end condition is slightly fiddly. In sufficiently strange - * degenerate grids, our test face may be adjacent to the same - * other face multiple times (typically if it's the exterior - * face). Consider this, in particular: - * - * +--+ - * | | - * +--+--+ - * | | | - * +--+--+ - * - * The bottom left face there is adjacent to the exterior face - * twice, so we can't just terminate our iteration when we reach - * the same _face_ we started at. Furthermore, we can't - * condition on having the same (i,j) pair either, because - * several (i,j) pairs identify the bottom left contiguity with - * the exterior face! We canonicalise the (i,j) pair by taking - * one step around before we set the termination tracking. - */ - - i = j = 0; - current_face = test_face->dots[0]->faces[0]; - if (current_face == test_face) { - j = 1; - current_face = test_face->dots[0]->faces[1]; - } - transitions = 0; - current_state = (FACE_COLOUR(current_face) == colour); - starting_dot = NULL; - starting_face = NULL; - while (TRUE) { - /* Advance to next face. - * Need to loop here because it might take several goes to - * find it. */ - while (TRUE) { - j++; - if (j == test_face->dots[i]->order) - j = 0; - - if (test_face->dots[i]->faces[j] == test_face) { - /* Advance to next dot round test_face, then - * find current_face around new dot - * and advance to the next face clockwise */ - i++; - if (i == test_face->order) - i = 0; - for (j = 0; j < test_face->dots[i]->order; j++) { - if (test_face->dots[i]->faces[j] == current_face) - break; - } - /* Must actually find current_face around new dot, - * or else something's wrong with the grid. */ - assert(j != test_face->dots[i]->order); - /* Found, so advance to next face and try again */ - } else { - break; - } - } - /* (i,j) are now advanced to next face */ - current_face = test_face->dots[i]->faces[j]; - s = (FACE_COLOUR(current_face) == colour); - if (!starting_dot) { - starting_dot = test_face->dots[i]; - starting_face = current_face; - current_state = s; - } else { - if (s != current_state) { - ++transitions; - current_state = s; - if (transitions > 2) - break; - } - if (test_face->dots[i] == starting_dot && - current_face == starting_face) - break; - } - } - - return (transitions == 2) ? TRUE : FALSE; -} - -/* Count the number of neighbours of 'face', having colour 'colour' */ -static int face_num_neighbours(grid *g, char *board, grid_face *face, - enum face_colour colour) -{ - int colour_count = 0; - int i; - grid_face *f; - grid_edge *e; - for (i = 0; i < face->order; i++) { - e = face->edges[i]; - f = (e->face1 == face) ? e->face2 : e->face1; - if (FACE_COLOUR(f) == colour) - ++colour_count; - } - return colour_count; -} - -/* The 'score' of a face reflects its current desirability for selection - * as the next face to colour white or black. We want to encourage moving - * into grey areas and increasing loopiness, so we give scores according to - * how many of the face's neighbours are currently coloured the same as the - * proposed colour. */ -static int face_score(grid *g, char *board, grid_face *face, - enum face_colour colour) -{ - /* Simple formula: score = 0 - num. same-coloured neighbours, - * so a higher score means fewer same-coloured neighbours. */ - return -face_num_neighbours(g, board, face, colour); -} - -/* Generate a new complete set of clues for the given game_state. - * The method is to generate a WHITE/BLACK colouring of all the faces, - * such that the WHITE faces will define the inside of the path, and the - * BLACK faces define the outside. - * To do this, we initially colour all faces GREY. The infinite space outside - * the grid is coloured BLACK, and we choose a random face to colour WHITE. - * Then we gradually grow the BLACK and the WHITE regions, eliminating GREY - * faces, until the grid is filled with BLACK/WHITE. As we grow the regions, - * we avoid creating loops of a single colour, to preserve the topological - * shape of the WHITE and BLACK regions. - * We also try to make the boundary as loopy and twisty as possible, to avoid - * generating paths that are uninteresting. - * The algorithm works by choosing a BLACK/WHITE colour, then choosing a GREY - * face that can be coloured with that colour (without violating the - * topological shape of that region). It's not obvious, but I think this - * algorithm is guaranteed to terminate without leaving any GREY faces behind. - * Indeed, if there are any GREY faces at all, both the WHITE and BLACK - * regions can be grown. - * This is checked using assert()ions, and I haven't seen any failures yet. - * - * Hand-wavy proof: imagine what can go wrong... - * - * Could the white faces get completely cut off by the black faces, and still - * leave some grey faces remaining? - * No, because then the black faces would form a loop around both the white - * faces and the grey faces, which is disallowed because we continually - * maintain the correct topological shape of the black region. - * Similarly, the black faces can never get cut off by the white faces. That - * means both the WHITE and BLACK regions always have some room to grow into - * the GREY regions. - * Could it be that we can't colour some GREY face, because there are too many - * WHITE/BLACK transitions as we walk round the face? (see the - * can_colour_face() function for details) - * No. Imagine otherwise, and we see WHITE/BLACK/WHITE/BLACK as we walk - * around the face. The two WHITE faces would be connected by a WHITE path, - * and the BLACK faces would be connected by a BLACK path. These paths would - * have to cross, which is impossible. - * Another thing that could go wrong: perhaps we can't find any GREY face to - * colour WHITE, because it would create a loop-violation or a corner-violation - * with the other WHITE faces? - * This is a little bit tricky to prove impossible. Imagine you have such a - * GREY face (that is, if you coloured it WHITE, you would create a WHITE loop - * or corner violation). - * That would cut all the non-white area into two blobs. One of those blobs - * must be free of BLACK faces (because the BLACK stuff is a connected blob). - * So we have a connected GREY area, completely surrounded by WHITE - * (including the GREY face we've tentatively coloured WHITE). - * A well-known result in graph theory says that you can always find a GREY - * face whose removal leaves the remaining GREY area connected. And it says - * there are at least two such faces, so we can always choose the one that - * isn't the "tentative" GREY face. Colouring that face WHITE leaves - * everything nice and connected, including that "tentative" GREY face which - * acts as a gateway to the rest of the non-WHITE grid. - */ static void add_full_clues(game_state *state, random_state *rs) { signed char *clues = state->clues; - char *board; grid *g = state->game_grid; - int i, j; - int num_faces = g->num_faces; - struct face_score *face_scores; /* Array of face_score objects */ - struct face_score *fs; /* Points somewhere in the above list */ - struct grid_face *cur_face; - tree234 *lightable_faces_sorted; - tree234 *darkable_faces_sorted; - int *face_list; - int do_random_pass; - - board = snewn(num_faces, char); - - /* Make a board */ - memset(board, FACE_GREY, num_faces); - - /* Create and initialise the list of face_scores */ - face_scores = snewn(num_faces, struct face_score); - for (i = 0; i < num_faces; i++) { - face_scores[i].random = random_bits(rs, 31); - face_scores[i].black_score = face_scores[i].white_score = 0; - } - - /* Colour a random, finite face white. The infinite face is implicitly - * coloured black. Together, they will seed the random growth process - * for the black and white areas. */ - i = random_upto(rs, num_faces); - board[i] = FACE_WHITE; - - /* We need a way of favouring faces that will increase our loopiness. - * We do this by maintaining a list of all candidate faces sorted by - * their score and choose randomly from that with appropriate skew. - * In order to avoid consistently biasing towards particular faces, we - * need the sort order _within_ each group of scores to be completely - * random. But it would be abusing the hospitality of the tree234 data - * structure if our comparison function were nondeterministic :-). So with - * each face we associate a random number that does not change during a - * particular run of the generator, and use that as a secondary sort key. - * Yes, this means we will be biased towards particular random faces in - * any one run but that doesn't actually matter. */ - - lightable_faces_sorted = newtree234(white_sort_cmpfn); - darkable_faces_sorted = newtree234(black_sort_cmpfn); - - /* Initialise the lists of lightable and darkable faces. This is - * slightly different from the code inside the while-loop, because we need - * to check every face of the board (the grid structure does not keep a - * list of the infinite face's neighbours). */ - for (i = 0; i < num_faces; i++) { - grid_face *f = g->faces + i; - struct face_score *fs = face_scores + i; - if (board[i] != FACE_GREY) continue; - /* We need the full colourability check here, it's not enough simply - * to check neighbourhood. On some grids, a neighbour of the infinite - * face is not necessarily darkable. */ - if (can_colour_face(g, board, i, FACE_BLACK)) { - fs->black_score = face_score(g, board, f, FACE_BLACK); - add234(darkable_faces_sorted, fs); - } - if (can_colour_face(g, board, i, FACE_WHITE)) { - fs->white_score = face_score(g, board, f, FACE_WHITE); - add234(lightable_faces_sorted, fs); - } - } - - /* Colour faces one at a time until no more faces are colourable. */ - while (TRUE) - { - enum face_colour colour; - struct face_score *fs_white, *fs_black; - int c_lightable = count234(lightable_faces_sorted); - int c_darkable = count234(darkable_faces_sorted); - if (c_lightable == 0 && c_darkable == 0) { - /* No more faces we can use at all. */ - break; - } - assert(c_lightable != 0 && c_darkable != 0); - - fs_white = (struct face_score *)index234(lightable_faces_sorted, 0); - fs_black = (struct face_score *)index234(darkable_faces_sorted, 0); - - /* Choose a colour, and colour the best available face - * with that colour. */ - colour = random_upto(rs, 2) ? FACE_WHITE : FACE_BLACK; - - if (colour == FACE_WHITE) - fs = fs_white; - else - fs = fs_black; - assert(fs); - i = fs - face_scores; - assert(board[i] == FACE_GREY); - board[i] = colour; - - /* Remove this newly-coloured face from the lists. These lists should - * only contain grey faces. */ - del234(lightable_faces_sorted, fs); - del234(darkable_faces_sorted, fs); - - /* Remember which face we've just coloured */ - cur_face = g->faces + i; - - /* The face we've just coloured potentially affects the colourability - * and the scores of any neighbouring faces (touching at a corner or - * edge). So the search needs to be conducted around all faces - * touching the one we've just lit. Iterate over its corners, then - * over each corner's faces. For each such face, we remove it from - * the lists, recalculate any scores, then add it back to the lists - * (depending on whether it is lightable, darkable or both). */ - for (i = 0; i < cur_face->order; i++) { - grid_dot *d = cur_face->dots[i]; - for (j = 0; j < d->order; j++) { - grid_face *f = d->faces[j]; - int fi; /* face index of f */ - - if (f == NULL) - continue; - if (f == cur_face) - continue; - - /* If the face is already coloured, it won't be on our - * lightable/darkable lists anyway, so we can skip it without - * bothering with the removal step. */ - if (FACE_COLOUR(f) != FACE_GREY) continue; - - /* Find the face index and face_score* corresponding to f */ - fi = f - g->faces; - fs = face_scores + fi; - - /* Remove from lightable list if it's in there. We do this, - * even if it is still lightable, because the score might - * be different, and we need to remove-then-add to maintain - * correct sort order. */ - del234(lightable_faces_sorted, fs); - if (can_colour_face(g, board, fi, FACE_WHITE)) { - fs->white_score = face_score(g, board, f, FACE_WHITE); - add234(lightable_faces_sorted, fs); - } - /* Do the same for darkable list. */ - del234(darkable_faces_sorted, fs); - if (can_colour_face(g, board, fi, FACE_BLACK)) { - fs->black_score = face_score(g, board, f, FACE_BLACK); - add234(darkable_faces_sorted, fs); - } - } - } - } - - /* Clean up */ - freetree234(lightable_faces_sorted); - freetree234(darkable_faces_sorted); - sfree(face_scores); - - /* The next step requires a shuffled list of all faces */ - face_list = snewn(num_faces, int); - for (i = 0; i < num_faces; ++i) { - face_list[i] = i; - } - shuffle(face_list, num_faces, sizeof(int), rs); - - /* The above loop-generation algorithm can often leave large clumps - * of faces of one colour. In extreme cases, the resulting path can be - * degenerate and not very satisfying to solve. - * This next step alleviates this problem: - * Go through the shuffled list, and flip the colour of any face we can - * legally flip, and which is adjacent to only one face of the opposite - * colour - this tends to grow 'tendrils' into any clumps. - * Repeat until we can find no more faces to flip. This will - * eventually terminate, because each flip increases the loop's - * perimeter, which cannot increase for ever. - * The resulting path will have maximal loopiness (in the sense that it - * cannot be improved "locally". Unfortunately, this allows a player to - * make some illicit deductions. To combat this (and make the path more - * interesting), we do one final pass making random flips. */ - - /* Set to TRUE for final pass */ - do_random_pass = FALSE; - - while (TRUE) { - /* Remember whether a flip occurred during this pass */ - int flipped = FALSE; - - for (i = 0; i < num_faces; ++i) { - int j = face_list[i]; - enum face_colour opp = - (board[j] == FACE_WHITE) ? FACE_BLACK : FACE_WHITE; - if (can_colour_face(g, board, j, opp)) { - grid_face *face = g->faces +j; - if (do_random_pass) { - /* final random pass */ - if (!random_upto(rs, 10)) - board[j] = opp; - } else { - /* normal pass - flip when neighbour count is 1 */ - if (face_num_neighbours(g, board, face, opp) == 1) { - board[j] = opp; - flipped = TRUE; - } - } - } - } - - if (do_random_pass) break; - if (!flipped) do_random_pass = TRUE; - } + char *board = snewn(g->num_faces, char); + int i; - sfree(face_list); + generate_loop(g, board, rs, NULL, NULL); /* Fill out all the clues by initialising to 0, then iterating over * all edges and incrementing each clue as we find edges that border * between BLACK/WHITE faces. While we're at it, we verify that the * algorithm does work, and there aren't any GREY faces still there. */ - memset(clues, 0, num_faces); + memset(clues, 0, g->num_faces); for (i = 0; i < g->num_edges; i++) { grid_edge *e = g->edges + i; grid_face *f1 = e->face1; @@ -1772,7 +1352,6 @@ static void add_full_clues(game_state *state, random_state *rs) if (f2) clues[f2 - g->faces]++; } } - sfree(board); } @@ -1832,20 +1411,22 @@ static game_state *remove_clues(game_state *state, random_state *rs, } -static char *new_game_desc(game_params *params, random_state *rs, +static char *new_game_desc(const game_params *params, random_state *rs, char **aux, int interactive) { /* solution and description both use run-length encoding in obvious ways */ - char *retval; + char *retval, *game_desc, *grid_desc; grid *g; game_state *state = snew(game_state); game_state *state_new; - params_generate_grid(params); - state->game_grid = g = params->game_grid; - g->refcount++; + + grid_desc = grid_new_desc(grid_types[params->type], params->w, params->h, rs); + state->game_grid = g = loopy_generate_grid(params, grid_desc); + state->clues = snewn(g->num_faces, signed char); state->lines = snewn(g->num_edges, char); state->line_errors = snewn(g->num_edges, unsigned char); + state->exactly_one_loop = FALSE; state->grid_type = params->type; @@ -1875,34 +1456,49 @@ static char *new_game_desc(game_params *params, random_state *rs, goto newboard_please; } - retval = state_to_text(state); + game_desc = state_to_text(state); free_game(state); + if (grid_desc) { + retval = snewn(strlen(grid_desc) + 1 + strlen(game_desc) + 1, char); + sprintf(retval, "%s%c%s", grid_desc, (int)GRID_DESC_SEP, game_desc); + sfree(grid_desc); + sfree(game_desc); + } else { + retval = game_desc; + } + assert(!validate_desc(params, retval)); return retval; } -static game_state *new_game(midend *me, game_params *params, char *desc) +static game_state *new_game(midend *me, const game_params *params, + const char *desc) { int i; game_state *state = snew(game_state); int empties_to_make = 0; int n,n2; - const char *dp = desc; + const char *dp; + char *grid_desc; grid *g; int num_faces, num_edges; - params_generate_grid(params); - state->game_grid = g = params->game_grid; - g->refcount++; + grid_desc = extract_grid_desc(&desc); + state->game_grid = g = loopy_generate_grid(params, grid_desc); + if (grid_desc) sfree(grid_desc); + + dp = desc; + num_faces = g->num_faces; num_edges = g->num_edges; state->clues = snewn(num_faces, signed char); state->lines = snewn(num_edges, char); state->line_errors = snewn(num_edges, unsigned char); + state->exactly_one_loop = FALSE; state->solved = state->cheated = FALSE; @@ -1941,141 +1537,119 @@ static game_state *new_game(midend *me, game_params *params, char *desc) static int check_completion(game_state *state) { grid *g = state->game_grid; - int *dsf; - int num_faces = g->num_faces; - int i; - int infinite_area, finite_area; - int loops_found = 0; - int found_edge_not_in_loop = FALSE; + int i, ret; + int *dsf, *component_state; + int nsilly, nloop, npath, largest_comp, largest_size, total_pathsize; + enum { COMP_NONE, COMP_LOOP, COMP_PATH, COMP_SILLY, COMP_EMPTY }; memset(state->line_errors, 0, g->num_edges); - /* LL implementation of SGT's idea: - * A loop will partition the grid into an inside and an outside. - * If there is more than one loop, the grid will be partitioned into - * even more distinct regions. We can therefore track equivalence of - * faces, by saying that two faces are equivalent when there is a non-YES - * edge between them. - * We could keep track of the number of connected components, by counting - * the number of dsf-merges that aren't no-ops. - * But we're only interested in 3 separate cases: - * no loops, one loop, more than one loop. + /* + * Find loops in the grid, and determine whether the puzzle is + * solved. + * + * Loopy is a bit more complicated than most puzzles that care + * about loop detection. In most of them, loops are simply + * _forbidden_; so the obviously right way to do + * error-highlighting during play is to light up a graph edge red + * iff it is part of a loop, which is exactly what the centralised + * findloop.c makes easy. + * + * But Loopy is unusual in that you're _supposed_ to be making a + * loop - and yet _some_ loops are not the right loop. So we need + * to be more discriminating, by identifying loops one by one and + * then thinking about which ones to highlight, and so findloop.c + * isn't quite the right tool for the job in this case. + * + * Worse still, consider situations in which the grid contains a + * loop and also some non-loop edges: there are some cases like + * this in which the user's intuitive expectation would be to + * highlight the loop (if you're only about half way through the + * puzzle and have accidentally made a little loop in some corner + * of the grid), and others in which they'd be more likely to + * expect you to highlight the non-loop edges (if you've just + * closed off a whole loop that you thought was the entire + * solution, but forgot some disconnected edges in a corner + * somewhere). So while it's easy enough to check whether the + * solution is _right_, highlighting the wrong parts is a tricky + * problem for this puzzle! + * + * I'd quite like, in some situations, to identify the largest + * loop among the player's YES edges, and then light up everything + * other than that. But finding the longest cycle in a graph is an + * NP-complete problem (because, in particular, it must return a + * Hamilton cycle if one exists). + * + * However, I think we can make the problem tractable by + * exercising the Puzzles principle that it isn't absolutely + * necessary to highlight _all_ errors: the key point is that by + * the time the user has filled in the whole grid, they should + * either have seen a completion flash, or have _some_ error + * highlight showing them why the solution isn't right. So in + * principle it would be *just about* good enough to highlight + * just one error in the whole grid, if there was really no better + * way. But we'd like to highlight as many errors as possible. + * + * In this case, I think the simple approach is to make use of the + * fact that no vertex may have degree > 2, and that's really + * simple to detect. So the plan goes like this: + * + * - Form the dsf of connected components of the graph vertices. * - * No loops: all faces are equivalent to the infinite face. - * One loop: only two equivalence classes - finite and infinite. - * >= 2 loops: there are 2 distinct finite regions. + * - Highlight an error at any vertex with degree > 2. (It so + * happens that we do this by lighting up all the edges + * incident to that vertex, but that's an output detail.) * - * So we simply make two passes through all the edges. - * In the first pass, we dsf-merge the two faces bordering each non-YES - * edge. - * In the second pass, we look for YES-edges bordering: - * a) two non-equivalent faces. - * b) two non-equivalent faces, and one of them is part of a different - * finite area from the first finite area we've seen. + * - Any component that contains such a vertex is now excluded + * from further consideration, because it already has a + * highlight. * - * An occurrence of a) means there is at least one loop. - * An occurrence of b) means there is more than one loop. - * Edges satisfying a) are marked as errors. + * - The remaining components have no vertex with degree > 2, and + * hence they all consist of either a simple loop, or a simple + * path with two endpoints. * - * While we're at it, we set a flag if we find a YES edge that is not - * part of a loop. - * This information will help decide, if there's a single loop, whether it - * is a candidate for being a solution (that is, all YES edges are part of - * this loop). + * - For these purposes, group together all the paths and imagine + * them to be a single component (because in most normal + * situations the player will gradually build up the solution + * _not_ all in one connected segment, but as lots of separate + * little path pieces that gradually connect to each other). * - * If there is a candidate loop, we then go through all clues and check - * they are all satisfied. If so, we have found a solution and we can - * unmark all line_errors. + * - After doing that, if there is exactly one (sensible) + * component - be it a collection of paths or a loop - then + * highlight no further edge errors. (The former case is normal + * during play, and the latter is a potentially solved puzzle.) + * + * - Otherwise, find the largest of the sensible components, + * leave that one unhighlighted, and light the rest up in red. */ - - /* Infinite face is at the end - its index is num_faces. - * This macro is just to make this obvious! */ - #define INF_FACE num_faces - dsf = snewn(num_faces + 1, int); - dsf_init(dsf, num_faces + 1); - - /* First pass */ - for (i = 0; i < g->num_edges; i++) { - grid_edge *e = g->edges + i; - int f1 = e->face1 ? e->face1 - g->faces : INF_FACE; - int f2 = e->face2 ? e->face2 - g->faces : INF_FACE; - if (state->lines[i] != LINE_YES) - dsf_merge(dsf, f1, f2); - } - - /* Second pass */ - infinite_area = dsf_canonify(dsf, INF_FACE); - finite_area = -1; - for (i = 0; i < g->num_edges; i++) { - grid_edge *e = g->edges + i; - int f1 = e->face1 ? e->face1 - g->faces : INF_FACE; - int can1 = dsf_canonify(dsf, f1); - int f2 = e->face2 ? e->face2 - g->faces : INF_FACE; - int can2 = dsf_canonify(dsf, f2); - if (state->lines[i] != LINE_YES) continue; - - if (can1 == can2) { - /* Faces are equivalent, so this edge not part of a loop */ - found_edge_not_in_loop = TRUE; - continue; - } - state->line_errors[i] = TRUE; - if (loops_found == 0) loops_found = 1; - - /* Don't bother with further checks if we've already found 2 loops */ - if (loops_found == 2) continue; - if (finite_area == -1) { - /* Found our first finite area */ - if (can1 != infinite_area) - finite_area = can1; - else - finite_area = can2; - } + dsf = snew_dsf(g->num_dots); - /* Have we found a second area? */ - if (finite_area != -1) { - if (can1 != infinite_area && can1 != finite_area) { - loops_found = 2; - continue; - } - if (can2 != infinite_area && can2 != finite_area) { - loops_found = 2; - } + /* Build the dsf. */ + for (i = 0; i < g->num_edges; i++) { + if (state->lines[i] == LINE_YES) { + grid_edge *e = g->edges + i; + int d1 = e->dot1 - g->dots, d2 = e->dot2 - g->dots; + dsf_merge(dsf, d1, d2); } } -/* - printf("loops_found = %d\n", loops_found); - printf("found_edge_not_in_loop = %s\n", - found_edge_not_in_loop ? "TRUE" : "FALSE"); -*/ - - sfree(dsf); /* No longer need the dsf */ - - /* Have we found a candidate loop? */ - if (loops_found == 1 && !found_edge_not_in_loop) { - /* Yes, so check all clues are satisfied */ - int found_clue_violation = FALSE; - for (i = 0; i < num_faces; i++) { - int c = state->clues[i]; - if (c >= 0) { - if (face_order(state, i, LINE_YES) != c) { - found_clue_violation = TRUE; - break; - } - } - } - - if (!found_clue_violation) { - /* The loop is good */ - memset(state->line_errors, 0, g->num_edges); - return TRUE; /* No need to bother checking for dot violations */ - } + /* Initialise a state variable for each connected component. */ + component_state = snewn(g->num_dots, int); + for (i = 0; i < g->num_dots; i++) { + if (dsf_canonify(dsf, i) == i) + component_state[i] = COMP_LOOP; + else + component_state[i] = COMP_NONE; } - /* Check for dot violations */ + /* Check for dots with degree > 3. Here we also spot dots of + * degree 1 in which the user has marked all the non-edges as + * LINE_NO, because those are also clear vertex-level errors, so + * we give them the same treatment of excluding their connected + * component from the subsequent loop analysis. */ for (i = 0; i < g->num_dots; i++) { + int comp = dsf_canonify(dsf, i); int yes = dot_order(state, i, LINE_YES); int unknown = dot_order(state, i, LINE_UNKNOWN); if ((yes == 1 && unknown == 0) || (yes >= 3)) { @@ -2087,9 +1661,108 @@ static int check_completion(game_state *state) if (state->lines[e] == LINE_YES) state->line_errors[e] = TRUE; } + /* And mark this component as not worthy of further + * consideration. */ + component_state[comp] = COMP_SILLY; + + } else if (yes == 0) { + /* A completely isolated dot must also be excluded it from + * the subsequent loop highlighting pass, but we tag it + * with a different enum value to avoid it counting + * towards the components that inhibit returning a win + * status. */ + component_state[comp] = COMP_EMPTY; + } else if (yes == 1) { + /* A dot with degree 1 that didn't fall into the 'clearly + * erroneous' case above indicates that this connected + * component will be a path rather than a loop - unless + * something worse elsewhere in the component has + * classified it as silly. */ + if (component_state[comp] != COMP_SILLY) + component_state[comp] = COMP_PATH; + } + } + + /* Count up the components. Also, find the largest sensible + * component. (Tie-breaking condition is derived from the order of + * vertices in the grid data structure, which is fairly arbitrary + * but at least stays stable throughout the game.) */ + nsilly = nloop = npath = 0; + total_pathsize = 0; + largest_comp = largest_size = -1; + for (i = 0; i < g->num_dots; i++) { + if (component_state[i] == COMP_SILLY) { + nsilly++; + } else if (component_state[i] == COMP_PATH) { + total_pathsize += dsf_size(dsf, i); + npath = 1; + } else if (component_state[i] == COMP_LOOP) { + int this_size; + + nloop++; + + if ((this_size = dsf_size(dsf, i)) > largest_size) { + largest_comp = i; + largest_size = this_size; + } } } - return FALSE; + if (largest_size < total_pathsize) { + largest_comp = -1; /* means the paths */ + largest_size = total_pathsize; + } + + if (nloop > 0 && nloop + npath > 1) { + /* + * If there are at least two sensible components including at + * least one loop, highlight all edges in every sensible + * component that is not the largest one. + */ + for (i = 0; i < g->num_edges; i++) { + if (state->lines[i] == LINE_YES) { + grid_edge *e = g->edges + i; + int d1 = e->dot1 - g->dots; /* either endpoint is good enough */ + int comp = dsf_canonify(dsf, d1); + if ((component_state[comp] == COMP_PATH && + -1 != largest_comp) || + (component_state[comp] == COMP_LOOP && + comp != largest_comp)) + state->line_errors[i] = TRUE; + } + } + } + + if (nloop == 1 && npath == 0 && nsilly == 0) { + /* + * If there is exactly one component and it is a loop, then + * the puzzle is potentially complete, so check the clues. + */ + ret = TRUE; + + for (i = 0; i < g->num_faces; i++) { + int c = state->clues[i]; + if (c >= 0 && face_order(state, i, LINE_YES) != c) { + ret = FALSE; + break; + } + } + + /* + * Also, whether or not the puzzle is actually complete, set + * the flag that says this game_state has exactly one loop and + * nothing else, which will be used to vary the semantics of + * clue highlighting at display time. + */ + state->exactly_one_loop = TRUE; + } else { + ret = FALSE; + state->exactly_one_loop = FALSE; + } + + sfree(component_state); + sfree(dsf); + + return ret; } /* ---------------------------------------------------------------------- @@ -3238,8 +2911,8 @@ static solver_state *solve_game_rec(const solver_state *sstate_start) return sstate; } -static char *solve_game(game_state *state, game_state *currstate, - char *aux, char **error) +static char *solve_game(const game_state *state, const game_state *currstate, + const char *aux, char **error) { char *soln = NULL; solver_state *sstate, *new_sstate; @@ -3267,13 +2940,15 @@ static char *solve_game(game_state *state, game_state *currstate, * Drawing and mouse-handling */ -static char *interpret_move(game_state *state, game_ui *ui, game_drawstate *ds, +static char *interpret_move(const game_state *state, game_ui *ui, + const game_drawstate *ds, int x, int y, int button) { grid *g = state->game_grid; grid_edge *e; int i; - char *ret, buf[80]; + char *movebuf; + int movelen, movesize; char button_char = ' '; enum line_state old_state; @@ -3335,14 +3010,86 @@ static char *interpret_move(game_state *state, game_ui *ui, game_drawstate *ds, return NULL; } + movelen = 0; + movesize = 80; + movebuf = snewn(movesize, char); + movelen = sprintf(movebuf, "%d%c", i, (int)button_char); + { + static enum { OFF, FIXED, ADAPTIVE, DUNNO } autofollow = DUNNO; + if (autofollow == DUNNO) { + const char *env = getenv("LOOPY_AUTOFOLLOW"); + if (env && !strcmp(env, "off")) + autofollow = OFF; + else if (env && !strcmp(env, "fixed")) + autofollow = FIXED; + else if (env && !strcmp(env, "adaptive")) + autofollow = ADAPTIVE; + else + autofollow = OFF; + } + + if (autofollow != OFF) { + int dotid; + for (dotid = 0; dotid < 2; dotid++) { + grid_dot *dot = (dotid == 0 ? e->dot1 : e->dot2); + grid_edge *e_this = e; + + while (1) { + int j, n_found; + grid_edge *e_next = NULL; + + for (j = n_found = 0; j < dot->order; j++) { + grid_edge *e_candidate = dot->edges[j]; + int i_candidate = e_candidate - g->edges; + if (e_candidate != e_this && + (autofollow == FIXED || + state->lines[i] == LINE_NO || + state->lines[i_candidate] != LINE_NO)) { + e_next = e_candidate; + n_found++; + } + } - sprintf(buf, "%d%c", i, (int)button_char); - ret = dupstr(buf); + if (n_found != 1 || + state->lines[e_next - g->edges] != state->lines[i]) + break; - return ret; + if (e_next == e) { + /* + * Special case: we might have come all the + * way round a loop and found our way back to + * the same edge we started from. In that + * situation, we must terminate not only this + * while loop, but the 'for' outside it that + * was tracing in both directions from the + * starting edge, because if we let it trace + * in the second direction then we'll only + * find ourself traversing the same loop in + * the other order and generate an encoded + * move string that mentions the same set of + * edges twice. + */ + goto autofollow_done; + } + + dot = (e_next->dot1 != dot ? e_next->dot1 : e_next->dot2); + if (movelen > movesize - 40) { + movesize = movesize * 5 / 4 + 128; + movebuf = sresize(movebuf, movesize, char); + } + e_this = e_next; + movelen += sprintf(movebuf+movelen, "%d%c", + (int)(e_this - g->edges), button_char); + } + } + autofollow_done:; + } + } + + return sresize(movebuf, movelen+1, char); } -static game_state *execute_move(game_state *state, char *move) +static game_state *execute_move(const game_state *state, const char *move) { int i; game_state *newstate = dup_game(state); @@ -3404,10 +3151,8 @@ static void grid_to_screen(const game_drawstate *ds, const grid *g, /* Returns (into x,y) position of centre of face for rendering the text clue. */ static void face_text_pos(const game_drawstate *ds, const grid *g, - const grid_face *f, int *xret, int *yret) + grid_face *f, int *xret, int *yret) { - int x, y, x0, y0, x1, y1, xbest, ybest, i, shift; - long bestdist; int faceindex = f - g->faces; /* @@ -3421,154 +3166,11 @@ static void face_text_pos(const game_drawstate *ds, const grid *g, } /* - * Otherwise, try to find the point in the polygon with the - * maximum distance to any edge or corner. - * - * Start by working out the face's bounding box, in grid - * coordinates. + * Otherwise, use the incentre computed by grid.c and convert it + * to screen coordinates. */ - x0 = x1 = f->dots[0]->x; - y0 = y1 = f->dots[0]->y; - for (i = 1; i < f->order; i++) { - if (x0 > f->dots[i]->x) x0 = f->dots[i]->x; - if (x1 < f->dots[i]->x) x1 = f->dots[i]->x; - if (y0 > f->dots[i]->y) y0 = f->dots[i]->y; - if (y1 < f->dots[i]->y) y1 = f->dots[i]->y; - } - - /* - * If the grid is at excessive resolution, decide on a scaling - * factor to bring it within reasonable bounds so we don't have to - * think too hard or suffer integer overflow. - */ - shift = 0; - while (x1 - x0 > 128 || y1 - y0 > 128) { - shift++; - x0 >>= 1; - x1 >>= 1; - y0 >>= 1; - y1 >>= 1; - } - - /* - * Now iterate over every point in that bounding box. - */ - xbest = ybest = -1; - bestdist = -1; - for (y = y0; y <= y1; y++) { - for (x = x0; x <= x1; x++) { - /* - * First, disqualify the point if it's not inside the - * polygon, which we work out by counting the edges to the - * right of the point. (For tiebreaking purposes when - * edges start or end on our y-coordinate or go right - * through it, we consider our point to be offset by a - * small _positive_ epsilon in both the x- and - * y-direction.) - */ - int in = 0; - for (i = 0; i < f->order; i++) { - int xs = f->edges[i]->dot1->x >> shift; - int xe = f->edges[i]->dot2->x >> shift; - int ys = f->edges[i]->dot1->y >> shift; - int ye = f->edges[i]->dot2->y >> shift; - if ((y >= ys && y < ye) || (y >= ye && y < ys)) { - /* - * The line goes past our y-position. Now we need - * to know if its x-coordinate when it does so is - * to our right. - * - * The x-coordinate in question is mathematically - * (y - ys) * (xe - xs) / (ye - ys), and we want - * to know whether (x - xs) >= that. Of course we - * avoid the division, so we can work in integers; - * to do this we must multiply both sides of the - * inequality by ye - ys, which means we must - * first check that's not negative. - */ - int num = xe - xs, denom = ye - ys; - if (denom < 0) { - num = -num; - denom = -denom; - } - if ((x - xs) * denom >= (y - ys) * num) - in ^= 1; - } - } - - if (in) { - long mindist = LONG_MAX; - - /* - * This point is inside the polygon, so now we check - * its minimum distance to every edge and corner. - * First the corners ... - */ - for (i = 0; i < f->order; i++) { - int xp = f->dots[i]->x >> shift; - int yp = f->dots[i]->y >> shift; - int dx = x - xp, dy = y - yp; - long dist = (long)dx*dx + (long)dy*dy; - if (mindist > dist) - mindist = dist; - } - - /* - * ... and now also check the perpendicular distance - * to every edge, if the perpendicular lies between - * the edge's endpoints. - */ - for (i = 0; i < f->order; i++) { - int xs = f->edges[i]->dot1->x >> shift; - int xe = f->edges[i]->dot2->x >> shift; - int ys = f->edges[i]->dot1->y >> shift; - int ye = f->edges[i]->dot2->y >> shift; - - /* - * If s and e are our endpoints, and p our - * candidate circle centre, the foot of a - * perpendicular from p to the line se lies - * between s and e if and only if (p-s).(e-s) lies - * strictly between 0 and (e-s).(e-s). - */ - int edx = xe - xs, edy = ye - ys; - int pdx = x - xs, pdy = y - ys; - long pde = (long)pdx * edx + (long)pdy * edy; - long ede = (long)edx * edx + (long)edy * edy; - if (0 < pde && pde < ede) { - /* - * Yes, the nearest point on this edge is - * closer than either endpoint, so we must - * take it into account by measuring the - * perpendicular distance to the edge and - * checking its square against mindist. - */ - - long pdre = (long)pdx * edy - (long)pdy * edx; - long sqlen = pdre * pdre / ede; - - if (mindist > sqlen) - mindist = sqlen; - } - } - - /* - * Right. Now we know the biggest circle around this - * point, so we can check it against bestdist. - */ - if (bestdist < mindist) { - bestdist = mindist; - xbest = x; - ybest = y; - } - } - } - } - - assert(bestdist >= 0); - - /* convert to screen coordinates */ - grid_to_screen(ds, g, xbest << shift, ybest << shift, + grid_find_incentre(f); + grid_to_screen(ds, g, f->ix, f->iy, &ds->textx[faceindex], &ds->texty[faceindex]); *xret = ds->textx[faceindex]; @@ -3591,19 +3193,14 @@ static void face_text_bbox(game_drawstate *ds, grid *g, grid_face *f, } static void game_redraw_clue(drawing *dr, game_drawstate *ds, - game_state *state, int i) + const game_state *state, int i) { grid *g = state->game_grid; grid_face *f = g->faces + i; int x, y; - char c[3]; + char c[20]; - if (state->clues[i] < 10) { - c[0] = CLUE2CHAR(state->clues[i]); - c[1] = '\0'; - } else { - sprintf(c, "%d", state->clues[i]); - } + sprintf(c, "%d", state->clues[i]); face_text_pos(ds, g, f, &x, &y); draw_text(dr, x, y, @@ -3655,12 +3252,11 @@ static const int loopy_line_redraw_phases[] = { #define NPHASES lenof(loopy_line_redraw_phases) static void game_redraw_line(drawing *dr, game_drawstate *ds, - game_state *state, int i, int phase) + const game_state *state, int i, int phase) { grid *g = state->game_grid; grid_edge *e = g->edges + i; int x1, x2, y1, y2; - int xmin, ymin, xmax, ymax; int line_colour; if (state->line_errors[i]) @@ -3680,11 +3276,6 @@ static void game_redraw_line(drawing *dr, game_drawstate *ds, grid_to_screen(ds, g, e->dot1->x, e->dot1->y, &x1, &y1); grid_to_screen(ds, g, e->dot2->x, e->dot2->y, &x2, &y2); - xmin = min(x1, x2); - xmax = max(x1, x2); - ymin = min(y1, y2); - ymax = max(y1, y2); - if (line_colour == COL_FAINT) { static int draw_faint_lines = -1; if (draw_faint_lines < 0) { @@ -3703,7 +3294,7 @@ static void game_redraw_line(drawing *dr, game_drawstate *ds, } static void game_redraw_dot(drawing *dr, game_drawstate *ds, - game_state *state, int i) + const game_state *state, int i) { grid *g = state->game_grid; grid_dot *d = g->dots + i; @@ -3725,7 +3316,8 @@ static int boxes_intersect(int x0, int y0, int w0, int h0, } static void game_redraw_in_rect(drawing *dr, game_drawstate *ds, - game_state *state, int x, int y, int w, int h) + const game_state *state, + int x, int y, int w, int h) { grid *g = state->game_grid; int i, phase; @@ -3735,9 +3327,11 @@ static void game_redraw_in_rect(drawing *dr, game_drawstate *ds, draw_rect(dr, x, y, w, h, COL_BACKGROUND); for (i = 0; i < g->num_faces; i++) { - face_text_bbox(ds, g, &g->faces[i], &bx, &by, &bw, &bh); - if (boxes_intersect(x, y, w, h, bx, by, bw, bh)) - game_redraw_clue(dr, ds, state, i); + if (state->clues[i] >= 0) { + face_text_bbox(ds, g, &g->faces[i], &bx, &by, &bw, &bh); + if (boxes_intersect(x, y, w, h, bx, by, bw, bh)) + game_redraw_clue(dr, ds, state, i); + } } for (phase = 0; phase < NPHASES; phase++) { for (i = 0; i < g->num_edges; i++) { @@ -3756,8 +3350,9 @@ static void game_redraw_in_rect(drawing *dr, game_drawstate *ds, draw_update(dr, x, y, w, h); } -static void game_redraw(drawing *dr, game_drawstate *ds, game_state *oldstate, - game_state *state, int dir, game_ui *ui, +static void game_redraw(drawing *dr, game_drawstate *ds, + const game_state *oldstate, const game_state *state, + int dir, const game_ui *ui, float animtime, float flashtime) { #define REDRAW_OBJECTS_LIMIT 16 /* Somewhat arbitrary tradeoff */ @@ -3796,60 +3391,100 @@ static void game_redraw(drawing *dr, game_drawstate *ds, game_state *oldstate, * what needs doing, and the second actually does it. */ - if (!ds->started) + if (!ds->started) { redraw_everything = TRUE; - else { - - /* First, trundle through the faces. */ - for (i = 0; i < g->num_faces; i++) { - grid_face *f = g->faces + i; - int sides = f->order; - int clue_mistake; - int clue_satisfied; - int n = state->clues[i]; - if (n < 0) - continue; - - clue_mistake = (face_order(state, i, LINE_YES) > n || - face_order(state, i, LINE_NO ) > (sides-n)); - clue_satisfied = (face_order(state, i, LINE_YES) == n && - face_order(state, i, LINE_NO ) == (sides-n)); - - if (clue_mistake != ds->clue_error[i] || - clue_satisfied != ds->clue_satisfied[i]) { - ds->clue_error[i] = clue_mistake; - ds->clue_satisfied[i] = clue_satisfied; - if (nfaces == REDRAW_OBJECTS_LIMIT) - redraw_everything = TRUE; - else - faces[nfaces++] = i; - } - } + /* + * But we must still go through the upcoming loops, so that we + * set up stuff in ds correctly for the initial redraw. + */ + } - /* Work out what the flash state needs to be. */ - if (flashtime > 0 && - (flashtime <= FLASH_TIME/3 || - flashtime >= FLASH_TIME*2/3)) { - flash_changed = !ds->flashing; - ds->flashing = TRUE; - } else { - flash_changed = ds->flashing; - ds->flashing = FALSE; - } + /* First, trundle through the faces. */ + for (i = 0; i < g->num_faces; i++) { + grid_face *f = g->faces + i; + int sides = f->order; + int yes_order, no_order; + int clue_mistake; + int clue_satisfied; + int n = state->clues[i]; + if (n < 0) + continue; - /* Now, trundle through the edges. */ - for (i = 0; i < g->num_edges; i++) { - char new_ds = - state->line_errors[i] ? DS_LINE_ERROR : state->lines[i]; - if (new_ds != ds->lines[i] || - (flash_changed && state->lines[i] == LINE_YES)) { - ds->lines[i] = new_ds; - if (nedges == REDRAW_OBJECTS_LIMIT) - redraw_everything = TRUE; - else - edges[nedges++] = i; - } - } + yes_order = face_order(state, i, LINE_YES); + if (state->exactly_one_loop) { + /* + * Special case: if the set of LINE_YES edges in the grid + * consists of exactly one loop and nothing else, then we + * switch to treating LINE_UNKNOWN the same as LINE_NO for + * purposes of clue checking. + * + * This is because some people like to play Loopy without + * using the right-click, i.e. never setting anything to + * LINE_NO. Without this special case, if a person playing + * in that style fills in what they think is a correct + * solution loop but in fact it has an underfilled clue, + * then we will display no victory flash and also no error + * highlight explaining why not. With this special case, + * we light up underfilled clues at the instant the loop + * is closed. (Of course, *overfilled* clues are fine + * either way.) + * + * (It might still be considered unfortunate that we can't + * warn this style of player any earlier, if they make a + * mistake very near the beginning which doesn't show up + * until they close the last edge of the loop. One other + * thing we _could_ do here is to treat any LINE_UNKNOWN + * as LINE_NO if either of its endpoints has yes-degree 2, + * reflecting the fact that setting that line to YES would + * be an obvious error. But I don't think even that could + * catch _all_ clue errors in a timely manner; I think + * there are some that won't be displayed until the loop + * is filled in, even so, and there's no way to avoid that + * with complete reliability except to switch to being a + * player who sets things to LINE_NO.) + */ + no_order = sides - yes_order; + } else { + no_order = face_order(state, i, LINE_NO); + } + + clue_mistake = (yes_order > n || no_order > (sides-n)); + clue_satisfied = (yes_order == n && no_order == (sides-n)); + + if (clue_mistake != ds->clue_error[i] || + clue_satisfied != ds->clue_satisfied[i]) { + ds->clue_error[i] = clue_mistake; + ds->clue_satisfied[i] = clue_satisfied; + if (nfaces == REDRAW_OBJECTS_LIMIT) + redraw_everything = TRUE; + else + faces[nfaces++] = i; + } + } + + /* Work out what the flash state needs to be. */ + if (flashtime > 0 && + (flashtime <= FLASH_TIME/3 || + flashtime >= FLASH_TIME*2/3)) { + flash_changed = !ds->flashing; + ds->flashing = TRUE; + } else { + flash_changed = ds->flashing; + ds->flashing = FALSE; + } + + /* Now, trundle through the edges. */ + for (i = 0; i < g->num_edges; i++) { + char new_ds = + state->line_errors[i] ? DS_LINE_ERROR : state->lines[i]; + if (new_ds != ds->lines[i] || + (flash_changed && state->lines[i] == LINE_YES)) { + ds->lines[i] = new_ds; + if (nedges == REDRAW_OBJECTS_LIMIT) + redraw_everything = TRUE; + else + edges[nedges++] = i; + } } /* Pass one is now done. Now we do the actual drawing. */ @@ -3885,8 +3520,8 @@ static void game_redraw(drawing *dr, game_drawstate *ds, game_state *oldstate, ds->started = TRUE; } -static float game_flash_length(game_state *oldstate, game_state *newstate, - int dir, game_ui *ui) +static float game_flash_length(const game_state *oldstate, + const game_state *newstate, int dir, game_ui *ui) { if (!oldstate->solved && newstate->solved && !oldstate->cheated && !newstate->cheated) { @@ -3896,12 +3531,12 @@ static float game_flash_length(game_state *oldstate, game_state *newstate, return 0.0F; } -static int game_is_solved(game_state *state) +static int game_status(const game_state *state) { - return state->solved; + return state->solved ? +1 : 0; } -static void game_print_size(game_params *params, float *x, float *y) +static void game_print_size(const game_params *params, float *x, float *y) { int pw, ph; @@ -3913,7 +3548,7 @@ static void game_print_size(game_params *params, float *x, float *y) *y = ph / 100.0F; } -static void game_print(drawing *dr, game_state *state, int tilesize) +static void game_print(drawing *dr, const game_state *state, int tilesize) { int ink = print_mono_colour(dr, 0); int i; @@ -3921,6 +3556,10 @@ static void game_print(drawing *dr, game_state *state, int tilesize) grid *g = state->game_grid; ds->tilesize = tilesize; + ds->textx = snewn(g->num_faces, int); + ds->texty = snewn(g->num_faces, int); + for (i = 0; i < g->num_faces; i++) + ds->textx[i] = ds->texty[i] = -1; for (i = 0; i < g->num_dots; i++) { int x, y; @@ -3935,10 +3574,9 @@ static void game_print(drawing *dr, game_state *state, int tilesize) grid_face *f = g->faces + i; int clue = state->clues[i]; if (clue >= 0) { - char c[2]; + char c[20]; int x, y; - c[0] = CLUE2CHAR(clue); - c[1] = '\0'; + sprintf(c, "%d", state->clues[i]); face_text_pos(ds, g, f, &x, &y); draw_text(dr, x, y, FONT_VARIABLE, ds->tilesize / 2, @@ -3990,6 +3628,9 @@ static void game_print(drawing *dr, game_state *state, int tilesize) } } } + + sfree(ds->textx); + sfree(ds->texty); } #ifdef COMBINED @@ -3999,7 +3640,7 @@ static void game_print(drawing *dr, game_state *state, int tilesize) const struct game thegame = { "Loopy", "games.loopy", "loopy", default_params, - game_fetch_preset, + NULL, game_preset_menu, decode_params, encode_params, free_params, @@ -4027,7 +3668,7 @@ const struct game thegame = { game_redraw, game_anim_length, game_flash_length, - game_is_solved, + game_status, TRUE, FALSE, game_print_size, game_print, FALSE /* wants_statusbar */, FALSE, game_timing_state, @@ -4160,3 +3801,5 @@ int main(int argc, char **argv) } #endif + +/* vim: set shiftwidth=4 tabstop=8: */