/*
- * loopy.c: An implementation of the Nikoli game 'Loop the loop'.
+ * loopy.c:
+ *
+ * An implementation of the Nikoli game 'Loop the loop'.
* (c) Mike Pinna, 2005, 2006
+ * Substantially rewritten to allowing for more general types of grid.
+ * (c) Lambros Lambrou 2008
*
* vim: set shiftwidth=4 :set textwidth=80:
- */
+ */
/*
- * TODO:
- *
- * - Setting very high recursion depth seems to cause memory munching: are we
- * recursing before checking completion, by any chance?
- *
- * - There's an interesting deductive technique which makes use of topology
- * rather than just graph theory. Each _square_ in the grid is either inside
- * or outside the loop; you can tell that two squares are on the same side
- * of the loop if they're separated by an x (or, more generally, by a path
- * crossing no LINE_UNKNOWNs and an even number of LINE_YESes), and on the
- * opposite side of the loop if they're separated by a line (or an odd
- * number of LINE_YESes and no LINE_UNKNOWNs). Oh, and any square separated
- * from the outside of the grid by a LINE_YES or a LINE_NO is on the inside
- * or outside respectively. So if you can track this for all squares, you
- * figure out the state of the line between a pair once their relative
- * insideness is known.
+ * Possible future solver enhancements:
+ *
+ * - There's an interesting deductive technique which makes use
+ * of topology rather than just graph theory. Each _face_ in
+ * the grid is either inside or outside the loop; you can tell
+ * that two faces are on the same side of the loop if they're
+ * separated by a LINE_NO (or, more generally, by a path
+ * crossing no LINE_UNKNOWNs and an even number of LINE_YESes),
+ * and on the opposite side of the loop if they're separated by
+ * a LINE_YES (or an odd number of LINE_YESes and no
+ * LINE_UNKNOWNs). Oh, and any face separated from the outside
+ * of the grid by a LINE_YES or a LINE_NO is on the inside or
+ * outside respectively. So if you can track this for all
+ * faces, you figure out the state of the line between a pair
+ * once their relative insideness is known.
+ * + The way I envisage this working is simply to keep an edsf
+ * of all _faces_, which indicates whether they're on
+ * opposite sides of the loop from one another. We also
+ * include a special entry in the edsf for the infinite
+ * exterior "face".
+ * + So, the simple way to do this is to just go through the
+ * edges: every time we see an edge in a state other than
+ * LINE_UNKNOWN which separates two faces that aren't in the
+ * same edsf class, we can rectify that by merging the
+ * classes. Then, conversely, an edge in LINE_UNKNOWN state
+ * which separates two faces that _are_ in the same edsf
+ * class can immediately have its state determined.
+ * + But you can go one better, if you're prepared to loop
+ * over all _pairs_ of edges. Suppose we have edges A and B,
+ * which respectively separate faces A1,A2 and B1,B2.
+ * Suppose that A,B are in the same edge-edsf class and that
+ * A1,B1 (wlog) are in the same face-edsf class; then we can
+ * immediately place A2,B2 into the same face-edsf class (as
+ * each other, not as A1 and A2) one way round or the other.
+ * And conversely again, if A1,B1 are in the same face-edsf
+ * class and so are A2,B2, then we can put A,B into the same
+ * face-edsf class.
+ * * Of course, this deduction requires a quadratic-time
+ * loop over all pairs of edges in the grid, so it should
+ * be reserved until there's nothing easier left to be
+ * done.
+ *
+ * - The generalised grid support has made me (SGT) notice a
+ * possible extension to the loop-avoidance code. When you have
+ * a path of connected edges such that no other edges at all
+ * are incident on any vertex in the middle of the path - or,
+ * alternatively, such that any such edges are already known to
+ * be LINE_NO - then you know those edges are either all
+ * LINE_YES or all LINE_NO. Hence you can mentally merge the
+ * entire path into a single long curly edge for the purposes
+ * of loop avoidance, and look directly at whether or not the
+ * extreme endpoints of the path are connected by some other
+ * route. I find this coming up fairly often when I play on the
+ * octagonal grid setting, so it might be worth implementing in
+ * the solver.
*
* - (Just a speed optimisation.) Consider some todo list queue where every
* time we modify something we mark it for consideration by other bits of
#include <stdio.h>
#include <stdlib.h>
+#include <stddef.h>
#include <string.h>
#include <assert.h>
#include <ctype.h>
#include "puzzles.h"
#include "tree234.h"
+#include "grid.h"
+#include "loopgen.h"
/* Debugging options */
-/*#define DEBUG_CACHES*/
-/*#define SHOW_WORKING*/
+
+/*
+#define DEBUG_CACHES
+#define SHOW_WORKING
+#define DEBUG_DLINES
+*/
/* ----------------------------------------------------------------------
* Struct, enum and function declarations
enum {
COL_BACKGROUND,
COL_FOREGROUND,
+ COL_LINEUNKNOWN,
COL_HIGHLIGHT,
COL_MISTAKE,
+ COL_SATISFIED,
+ COL_FAINT,
NCOLOURS
};
struct game_state {
- int w, h;
-
- /* Put -1 in a square that doesn't get a clue */
- char *clues;
-
- /* Arrays of line states, stored left-to-right, top-to-bottom */
- char *hl, *vl;
+ grid *game_grid; /* ref-counted (internally) */
+
+ /* Put -1 in a face that doesn't get a clue */
+ signed char *clues;
+
+ /* Array of line states, to store whether each line is
+ * YES, NO or UNKNOWN */
+ char *lines;
+
+ unsigned char *line_errors;
+ int exactly_one_loop;
int solved;
int cheated;
- int recursion_depth;
+ /* Used in game_text_format(), so that it knows what type of
+ * grid it's trying to render as ASCII text. */
+ int grid_type;
};
enum solver_status {
SOLVER_INCOMPLETE /* This may be a partial solution */
};
-typedef struct normal {
- char *dot_atleastone;
- char *dot_atmostone;
-} normal_mode_state;
-
-typedef struct hard {
- int *linedsf;
-} hard_mode_state;
-
+/* ------ Solver state ------ */
typedef struct solver_state {
game_state *state;
- int recursion_remaining;
enum solver_status solver_status;
/* NB looplen is the number of dots that are joined together at a point, ie a
* looplen of 1 means there are no lines to a particular dot */
int *looplen;
+ /* Difficulty level of solver. Used by solver functions that want to
+ * vary their behaviour depending on the requested difficulty level. */
+ int diff;
+
/* caches */
- char *dot_yescount;
- char *dot_nocount;
- char *square_yescount;
- char *square_nocount;
- char *dot_solved, *square_solved;
+ char *dot_yes_count;
+ char *dot_no_count;
+ char *face_yes_count;
+ char *face_no_count;
+ char *dot_solved, *face_solved;
int *dotdsf;
- normal_mode_state *normal;
- hard_mode_state *hard;
+ /* Information for Normal level deductions:
+ * For each dline, store a bitmask for whether we know:
+ * (bit 0) at least one is YES
+ * (bit 1) at most one is YES */
+ char *dlines;
+
+ /* Hard level information */
+ int *linedsf;
} solver_state;
/*
*/
#define DIFFLIST(A) \
- A(EASY,Easy,e,easy_mode_deductions) \
- A(NORMAL,Normal,n,normal_mode_deductions) \
- A(HARD,Hard,h,hard_mode_deductions)
-#define ENUM(upper,title,lower,fn) DIFF_ ## upper,
-#define TITLE(upper,title,lower,fn) #title,
-#define ENCODE(upper,title,lower,fn) #lower
-#define CONFIG(upper,title,lower,fn) ":" #title
-#define SOLVER_FN_DECL(upper,title,lower,fn) static int fn(solver_state *);
-#define SOLVER_FN(upper,title,lower,fn) &fn,
+ A(EASY,Easy,e) \
+ A(NORMAL,Normal,n) \
+ A(TRICKY,Tricky,t) \
+ A(HARD,Hard,h)
+#define ENUM(upper,title,lower) DIFF_ ## upper,
+#define TITLE(upper,title,lower) #title,
+#define ENCODE(upper,title,lower) #lower
+#define CONFIG(upper,title,lower) ":" #title
enum { DIFFLIST(ENUM) DIFF_MAX };
static char const *const diffnames[] = { DIFFLIST(TITLE) };
static char const diffchars[] = DIFFLIST(ENCODE);
#define DIFFCONFIG DIFFLIST(CONFIG)
-DIFFLIST(SOLVER_FN_DECL);
-static int (*(solver_fns[]))(solver_state *) = { DIFFLIST(SOLVER_FN) };
+
+/*
+ * Solver routines, sorted roughly in order of computational cost.
+ * The solver will run the faster deductions first, and slower deductions are
+ * only invoked when the faster deductions are unable to make progress.
+ * Each function is associated with a difficulty level, so that the generated
+ * puzzles are solvable by applying only the functions with the chosen
+ * difficulty level or lower.
+ */
+#define SOLVERLIST(A) \
+ A(trivial_deductions, DIFF_EASY) \
+ A(dline_deductions, DIFF_NORMAL) \
+ A(linedsf_deductions, DIFF_HARD) \
+ A(loop_deductions, DIFF_EASY)
+#define SOLVER_FN_DECL(fn,diff) static int fn(solver_state *);
+#define SOLVER_FN(fn,diff) &fn,
+#define SOLVER_DIFF(fn,diff) diff,
+SOLVERLIST(SOLVER_FN_DECL)
+static int (*(solver_fns[]))(solver_state *) = { SOLVERLIST(SOLVER_FN) };
+static int const solver_diffs[] = { SOLVERLIST(SOLVER_DIFF) };
+static const int NUM_SOLVERS = sizeof(solver_diffs)/sizeof(*solver_diffs);
struct game_params {
int w, h;
int diff;
- int rec;
+ int type;
};
+/* line_drawstate is the same as line_state, but with the extra ERROR
+ * possibility. The drawing code copies line_state to line_drawstate,
+ * except in the case that the line is an error. */
enum line_state { LINE_YES, LINE_UNKNOWN, LINE_NO };
+enum line_drawstate { DS_LINE_YES, DS_LINE_UNKNOWN,
+ DS_LINE_NO, DS_LINE_ERROR };
-#define OPP(state) \
- (2 - state)
+#define OPP(line_state) \
+ (2 - line_state)
-enum direction { UP, LEFT, RIGHT, DOWN };
-
-#define OPP_DIR(dir) \
- (3 - dir)
struct game_drawstate {
int started;
- int tilesize, linewidth;
+ int tilesize;
int flashing;
- char *hl, *vl;
+ int *textx, *texty;
+ char *lines;
char *clue_error;
+ char *clue_satisfied;
};
-static char *game_text_format(game_state *state);
-static char *state_to_text(const game_state *state);
-static char *validate_desc(game_params *params, char *desc);
-static int get_line_status_from_point(const game_state *state,
- int x, int y, enum direction d);
-static int dot_order(const game_state* state, int i, int j, char line_type);
-static int square_order(const game_state* state, int i, int j, char line_type);
-static solver_state *solve_game_rec(const solver_state *sstate,
- int diff);
+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);
#ifdef DEBUG_CACHES
static void check_caches(const solver_state* sstate);
#define check_caches(s)
#endif
+/* ------- List of grid generators ------- */
+#define GRIDLIST(A) \
+ A(Squares,GRID_SQUARE,3,3) \
+ A(Triangular,GRID_TRIANGULAR,3,3) \
+ A(Honeycomb,GRID_HONEYCOMB,3,3) \
+ A(Snub-Square,GRID_SNUBSQUARE,3,3) \
+ A(Cairo,GRID_CAIRO,3,4) \
+ A(Great-Hexagonal,GRID_GREATHEXAGONAL,3,3) \
+ A(Octagonal,GRID_OCTAGONAL,3,3) \
+ A(Kites,GRID_KITE,3,3) \
+ A(Floret,GRID_FLORET,1,2) \
+ A(Dodecagonal,GRID_DODECAGONAL,2,2) \
+ A(Great-Dodecagonal,GRID_GREATDODECAGONAL,2,2) \
+ A(Penrose (kite/dart),GRID_PENROSE_P2,3,3) \
+ A(Penrose (rhombs),GRID_PENROSE_P3,3,3)
+
+#define GRID_NAME(title,type,amin,omin) #title,
+#define GRID_CONFIG(title,type,amin,omin) ":" #title
+#define GRID_TYPE(title,type,amin,omin) 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,},
+static char const *const gridnames[] = { GRIDLIST(GRID_NAME) };
+#define GRID_CONFIGS GRIDLIST(GRID_CONFIG)
+static grid_type grid_types[] = { GRIDLIST(GRID_TYPE) };
+#define NUM_GRID_TYPES (sizeof(grid_types) / sizeof(grid_types[0]))
+static const struct {
+ int amin, omin;
+ char *aerr, *oerr;
+} grid_size_limits[] = { GRIDLIST(GRID_SIZES) };
+
+/* Generates a (dynamically allocated) new grid, according to the
+ * type and size requested in params. Does nothing if the grid is already
+ * generated. */
+static grid *loopy_generate_grid(const game_params *params,
+ const char *grid_desc)
+{
+ return grid_new(grid_types[params->type], params->w, params->h, grid_desc);
+}
+
/* ----------------------------------------------------------------------
- * Preprocessor magic
+ * Preprocessor magic
*/
/* General constants */
#define PREFERRED_TILE_SIZE 32
-#define TILE_SIZE (ds->tilesize)
-#define LINEWIDTH (ds->linewidth)
-#define BORDER (TILE_SIZE / 2)
+#define BORDER(tilesize) ((tilesize) / 2)
#define FLASH_TIME 0.5F
-/* Counts of various things that we're interested in */
-#define HL_COUNT(state) ((state)->w * ((state)->h + 1))
-#define VL_COUNT(state) (((state)->w + 1) * (state)->h)
-#define LINE_COUNT(state) (HL_COUNT(state) + VL_COUNT(state))
-#define DOT_COUNT(state) (((state)->w + 1) * ((state)->h + 1))
-#define SQUARE_COUNT(state) ((state)->w * (state)->h)
-
-/* For indexing into arrays */
-#define DOT_INDEX(state, x, y) ((x) + ((state)->w + 1) * (y))
-#define SQUARE_INDEX(state, x, y) ((x) + ((state)->w) * (y))
-#define HL_INDEX(state, x, y) SQUARE_INDEX(state, x, y)
-#define VL_INDEX(state, x, y) DOT_INDEX(state, x, y)
-
-/* Useful utility functions */
-#define LEGAL_DOT(state, i, j) ((i) >= 0 && (j) >= 0 && \
- (i) <= (state)->w && (j) <= (state)->h)
-#define LEGAL_SQUARE(state, i, j) ((i) >= 0 && (j) >= 0 && \
- (i) < (state)->w && (j) < (state)->h)
-
-#define CLUE_AT(state, i, j) (LEGAL_SQUARE(state, i, j) ? \
- LV_CLUE_AT(state, i, j) : -1)
-
-#define LV_CLUE_AT(state, i, j) ((state)->clues[SQUARE_INDEX(state, i, j)])
-
#define BIT_SET(field, bit) ((field) & (1<<(bit)))
#define SET_BIT(field, bit) (BIT_SET(field, bit) ? FALSE : \
#define CLEAR_BIT(field, bit) (BIT_SET(field, bit) ? \
((field) &= ~(1<<(bit)), TRUE) : FALSE)
-#define DIR2STR(d) \
- ((d == UP) ? "up" : \
- (d == DOWN) ? "down" : \
- (d == LEFT) ? "left" : \
- (d == RIGHT) ? "right" : "oops")
-
#define CLUE2CHAR(c) \
- ((c < 0) ? ' ' : c + '0')
-
-/* Lines that have particular relationships with given dots or squares */
-#define ABOVE_SQUARE(state, i, j) ((state)->hl[(i) + (state)->w * (j)])
-#define BELOW_SQUARE(state, i, j) ABOVE_SQUARE(state, i, (j)+1)
-#define LEFTOF_SQUARE(state, i, j) ((state)->vl[(i) + ((state)->w + 1) * (j)])
-#define RIGHTOF_SQUARE(state, i, j) LEFTOF_SQUARE(state, (i)+1, j)
-
-/*
- * These macros return rvalues only, but can cope with being passed
- * out-of-range coordinates.
- */
-/* XXX replace these with functions so we can create an array of function
- * pointers for nicer iteration over them. This could probably be done with
- * loads of other things for eliminating many nasty hacks. */
-#define ABOVE_DOT(state, i, j) ((!LEGAL_DOT(state, i, j) || j <= 0) ? \
- LINE_NO : LV_ABOVE_DOT(state, i, j))
-#define BELOW_DOT(state, i, j) ((!LEGAL_DOT(state, i, j) || j >= (state)->h) ? \
- LINE_NO : LV_BELOW_DOT(state, i, j))
-
-#define LEFTOF_DOT(state, i, j) ((!LEGAL_DOT(state, i, j) || i <= 0) ? \
- LINE_NO : LV_LEFTOF_DOT(state, i, j))
-#define RIGHTOF_DOT(state, i, j) ((!LEGAL_DOT(state, i, j) || i >= (state)->w)? \
- LINE_NO : LV_RIGHTOF_DOT(state, i, j))
-
-/*
- * These macros expect to be passed valid coordinates, and return
- * lvalues.
- */
-#define LV_BELOW_DOT(state, i, j) ((state)->vl[VL_INDEX(state, i, j)])
-#define LV_ABOVE_DOT(state, i, j) LV_BELOW_DOT(state, i, (j)-1)
-
-#define LV_RIGHTOF_DOT(state, i, j) ((state)->hl[HL_INDEX(state, i, j)])
-#define LV_LEFTOF_DOT(state, i, j) LV_RIGHTOF_DOT(state, (i)-1, j)
-
-/* Counts of interesting things */
-#define DOT_YES_COUNT(sstate, i, j) \
- ((sstate)->dot_yescount[DOT_INDEX((sstate)->state, i, j)])
-
-#define DOT_NO_COUNT(sstate, i, j) \
- ((sstate)->dot_nocount[DOT_INDEX((sstate)->state, i, j)])
-
-#define SQUARE_YES_COUNT(sstate, i, j) \
- ((sstate)->square_yescount[SQUARE_INDEX((sstate)->state, i, j)])
-
-#define SQUARE_NO_COUNT(sstate, i, j) \
- ((sstate)->square_nocount[SQUARE_INDEX((sstate)->state, i, j)])
-
-/* Iterators. NB these iterate over height more slowly than over width so that
- * the elements come out in 'reading' order */
-/* XXX considering adding a 'current' element to each of these which gets the
- * address of the current dot, say. But expecting we'd need more than that
- * most of the time. */
-#define FORALL(i, j, w, h) \
- for ((j) = 0; (j) < (h); ++(j)) \
- for ((i) = 0; (i) < (w); ++(i))
-
-#define FORALL_DOTS(state, i, j) \
- FORALL(i, j, (state)->w + 1, (state)->h + 1)
-
-#define FORALL_SQUARES(state, i, j) \
- FORALL(i, j, (state)->w, (state)->h)
-
-#define FORALL_HL(state, i, j) \
- FORALL(i, j, (state)->w, (state)->h+1)
-
-#define FORALL_VL(state, i, j) \
- FORALL(i, j, (state)->w+1, (state)->h)
+ ((c < 0) ? ' ' : c < 10 ? c + '0' : c - 10 + 'A')
/* ----------------------------------------------------------------------
* 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);
- ret->h = state->h;
- ret->w = state->w;
+ ret->game_grid = state->game_grid;
+ ret->game_grid->refcount++;
+
ret->solved = state->solved;
ret->cheated = state->cheated;
- ret->clues = snewn(SQUARE_COUNT(state), char);
- memcpy(ret->clues, state->clues, SQUARE_COUNT(state));
-
- ret->hl = snewn(HL_COUNT(state), char);
- memcpy(ret->hl, state->hl, HL_COUNT(state));
+ ret->clues = snewn(state->game_grid->num_faces, signed char);
+ memcpy(ret->clues, state->clues, state->game_grid->num_faces);
- ret->vl = snewn(VL_COUNT(state), char);
- memcpy(ret->vl, state->vl, VL_COUNT(state));
+ ret->lines = snewn(state->game_grid->num_edges, char);
+ memcpy(ret->lines, state->lines, state->game_grid->num_edges);
- ret->recursion_depth = state->recursion_depth;
+ 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;
}
static void free_game(game_state *state)
{
if (state) {
+ grid_free(state->game_grid);
sfree(state->clues);
- sfree(state->hl);
- sfree(state->vl);
+ sfree(state->lines);
+ sfree(state->line_errors);
sfree(state);
}
}
static solver_state *new_solver_state(const game_state *state, int diff) {
- int i, j;
+ int i;
+ int num_dots = state->game_grid->num_dots;
+ int num_faces = state->game_grid->num_faces;
+ int num_edges = state->game_grid->num_edges;
solver_state *ret = snew(solver_state);
- ret->state = dup_game((game_state *)state);
-
- ret->recursion_remaining = state->recursion_depth;
- ret->solver_status = SOLVER_INCOMPLETE;
+ ret->state = dup_game(state);
+
+ ret->solver_status = SOLVER_INCOMPLETE;
+ ret->diff = diff;
- ret->dotdsf = snew_dsf(DOT_COUNT(state));
- ret->looplen = snewn(DOT_COUNT(state), int);
+ ret->dotdsf = snew_dsf(num_dots);
+ ret->looplen = snewn(num_dots, int);
- for (i = 0; i < DOT_COUNT(state); i++) {
+ for (i = 0; i < num_dots; i++) {
ret->looplen[i] = 1;
}
- ret->dot_solved = snewn(DOT_COUNT(state), char);
- ret->square_solved = snewn(SQUARE_COUNT(state), char);
- memset(ret->dot_solved, FALSE, DOT_COUNT(state));
- memset(ret->square_solved, FALSE, SQUARE_COUNT(state));
-
- ret->dot_yescount = snewn(DOT_COUNT(state), char);
- memset(ret->dot_yescount, 0, DOT_COUNT(state));
- ret->dot_nocount = snewn(DOT_COUNT(state), char);
- memset(ret->dot_nocount, 0, DOT_COUNT(state));
- ret->square_yescount = snewn(SQUARE_COUNT(state), char);
- memset(ret->square_yescount, 0, SQUARE_COUNT(state));
- ret->square_nocount = snewn(SQUARE_COUNT(state), char);
- memset(ret->square_nocount, 0, SQUARE_COUNT(state));
-
- /* dot_nocount needs special initialisation as we define lines coming off
- * dots on edges as fixed at NO */
+ ret->dot_solved = snewn(num_dots, char);
+ ret->face_solved = snewn(num_faces, char);
+ memset(ret->dot_solved, FALSE, num_dots);
+ memset(ret->face_solved, FALSE, num_faces);
- FORALL_DOTS(state, i, j) {
- if (i == 0 || i == state->w)
- ++ret->dot_nocount[DOT_INDEX(state, i, j)];
- if (j == 0 || j == state->h)
- ++ret->dot_nocount[DOT_INDEX(state, i, j)];
- }
+ ret->dot_yes_count = snewn(num_dots, char);
+ memset(ret->dot_yes_count, 0, num_dots);
+ ret->dot_no_count = snewn(num_dots, char);
+ memset(ret->dot_no_count, 0, num_dots);
+ ret->face_yes_count = snewn(num_faces, char);
+ memset(ret->face_yes_count, 0, num_faces);
+ ret->face_no_count = snewn(num_faces, char);
+ memset(ret->face_no_count, 0, num_faces);
if (diff < DIFF_NORMAL) {
- ret->normal = NULL;
+ ret->dlines = NULL;
} else {
- ret->normal = snew(normal_mode_state);
-
- ret->normal->dot_atmostone = snewn(DOT_COUNT(state), char);
- memset(ret->normal->dot_atmostone, 0, DOT_COUNT(state));
- ret->normal->dot_atleastone = snewn(DOT_COUNT(state), char);
- memset(ret->normal->dot_atleastone, 0, DOT_COUNT(state));
+ ret->dlines = snewn(2*num_edges, char);
+ memset(ret->dlines, 0, 2*num_edges);
}
if (diff < DIFF_HARD) {
- ret->hard = NULL;
+ ret->linedsf = NULL;
} else {
- ret->hard = snew(hard_mode_state);
- ret->hard->linedsf = snew_dsf(LINE_COUNT(state));
+ ret->linedsf = snew_dsf(state->game_grid->num_edges);
}
return ret;
sfree(sstate->dotdsf);
sfree(sstate->looplen);
sfree(sstate->dot_solved);
- sfree(sstate->square_solved);
- sfree(sstate->dot_yescount);
- sfree(sstate->dot_nocount);
- sfree(sstate->square_yescount);
- sfree(sstate->square_nocount);
-
- if (sstate->normal) {
- sfree(sstate->normal->dot_atleastone);
- sfree(sstate->normal->dot_atmostone);
- sfree(sstate->normal);
- }
+ sfree(sstate->face_solved);
+ sfree(sstate->dot_yes_count);
+ sfree(sstate->dot_no_count);
+ sfree(sstate->face_yes_count);
+ sfree(sstate->face_no_count);
- if (sstate->hard) {
- sfree(sstate->hard->linedsf);
- sfree(sstate->hard);
- }
+ /* OK, because sfree(NULL) is a no-op */
+ sfree(sstate->dlines);
+ sfree(sstate->linedsf);
sfree(sstate);
}
}
static solver_state *dup_solver_state(const solver_state *sstate) {
- game_state *state;
-
+ game_state *state = sstate->state;
+ int num_dots = state->game_grid->num_dots;
+ int num_faces = state->game_grid->num_faces;
+ int num_edges = state->game_grid->num_edges;
solver_state *ret = snew(solver_state);
ret->state = state = dup_game(sstate->state);
- ret->recursion_remaining = sstate->recursion_remaining;
ret->solver_status = sstate->solver_status;
-
- ret->dotdsf = snewn(DOT_COUNT(state), int);
- ret->looplen = snewn(DOT_COUNT(state), int);
- memcpy(ret->dotdsf, sstate->dotdsf,
- DOT_COUNT(state) * sizeof(int));
- memcpy(ret->looplen, sstate->looplen,
- DOT_COUNT(state) * sizeof(int));
-
- ret->dot_solved = snewn(DOT_COUNT(state), char);
- ret->square_solved = snewn(SQUARE_COUNT(state), char);
- memcpy(ret->dot_solved, sstate->dot_solved,
- DOT_COUNT(state));
- memcpy(ret->square_solved, sstate->square_solved,
- SQUARE_COUNT(state));
-
- ret->dot_yescount = snewn(DOT_COUNT(state), char);
- memcpy(ret->dot_yescount, sstate->dot_yescount,
- DOT_COUNT(state));
- ret->dot_nocount = snewn(DOT_COUNT(state), char);
- memcpy(ret->dot_nocount, sstate->dot_nocount,
- DOT_COUNT(state));
-
- ret->square_yescount = snewn(SQUARE_COUNT(state), char);
- memcpy(ret->square_yescount, sstate->square_yescount,
- SQUARE_COUNT(state));
- ret->square_nocount = snewn(SQUARE_COUNT(state), char);
- memcpy(ret->square_nocount, sstate->square_nocount,
- SQUARE_COUNT(state));
-
- if (sstate->normal) {
- ret->normal = snew(normal_mode_state);
- ret->normal->dot_atmostone = snewn(DOT_COUNT(state), char);
- memcpy(ret->normal->dot_atmostone, sstate->normal->dot_atmostone,
- DOT_COUNT(state));
-
- ret->normal->dot_atleastone = snewn(DOT_COUNT(state), char);
- memcpy(ret->normal->dot_atleastone, sstate->normal->dot_atleastone,
- DOT_COUNT(state));
+ ret->diff = sstate->diff;
+
+ ret->dotdsf = snewn(num_dots, int);
+ ret->looplen = snewn(num_dots, int);
+ memcpy(ret->dotdsf, sstate->dotdsf,
+ num_dots * sizeof(int));
+ memcpy(ret->looplen, sstate->looplen,
+ num_dots * sizeof(int));
+
+ ret->dot_solved = snewn(num_dots, char);
+ ret->face_solved = snewn(num_faces, char);
+ memcpy(ret->dot_solved, sstate->dot_solved, num_dots);
+ memcpy(ret->face_solved, sstate->face_solved, num_faces);
+
+ ret->dot_yes_count = snewn(num_dots, char);
+ memcpy(ret->dot_yes_count, sstate->dot_yes_count, num_dots);
+ ret->dot_no_count = snewn(num_dots, char);
+ memcpy(ret->dot_no_count, sstate->dot_no_count, num_dots);
+
+ ret->face_yes_count = snewn(num_faces, char);
+ memcpy(ret->face_yes_count, sstate->face_yes_count, num_faces);
+ ret->face_no_count = snewn(num_faces, char);
+ memcpy(ret->face_no_count, sstate->face_no_count, num_faces);
+
+ if (sstate->dlines) {
+ ret->dlines = snewn(2*num_edges, char);
+ memcpy(ret->dlines, sstate->dlines,
+ 2*num_edges);
} else {
- ret->normal = NULL;
+ ret->dlines = NULL;
}
- if (sstate->hard) {
- ret->hard = snew(hard_mode_state);
- ret->hard->linedsf = snewn(LINE_COUNT(state), int);
- memcpy(ret->hard->linedsf, sstate->hard->linedsf,
- LINE_COUNT(state) * sizeof(int));
+ if (sstate->linedsf) {
+ ret->linedsf = snewn(num_edges, int);
+ memcpy(ret->linedsf, sstate->linedsf,
+ num_edges * sizeof(int));
} else {
- ret->hard = NULL;
+ ret->linedsf = NULL;
}
return ret;
game_params *ret = snew(game_params);
#ifdef SLOW_SYSTEM
- ret->h = 4;
- ret->w = 4;
+ ret->h = 7;
+ ret->w = 7;
#else
ret->h = 10;
ret->w = 10;
#endif
ret->diff = DIFF_EASY;
- ret->rec = 0;
+ ret->type = 0;
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 */
return ret;
}
static const game_params presets[] = {
- { 4, 4, DIFF_EASY, 0 },
- { 4, 4, DIFF_NORMAL, 0 },
- { 4, 4, DIFF_HARD, 0 },
+#ifdef SMALL_SCREEN
+ { 7, 7, DIFF_EASY, 0 },
+ { 7, 7, DIFF_NORMAL, 0 },
+ { 7, 7, DIFF_HARD, 0 },
+ { 7, 7, DIFF_HARD, 1 },
+ { 7, 7, DIFF_HARD, 2 },
+ { 5, 5, DIFF_HARD, 3 },
+ { 7, 7, DIFF_HARD, 4 },
+ { 5, 4, DIFF_HARD, 5 },
+ { 5, 5, DIFF_HARD, 6 },
+ { 5, 5, DIFF_HARD, 7 },
+ { 3, 3, DIFF_HARD, 8 },
+ { 3, 3, DIFF_HARD, 9 },
+ { 3, 3, DIFF_HARD, 10 },
+ { 6, 6, DIFF_HARD, 11 },
+ { 6, 6, DIFF_HARD, 12 },
+#else
{ 7, 7, DIFF_EASY, 0 },
+ { 10, 10, DIFF_EASY, 0 },
{ 7, 7, DIFF_NORMAL, 0 },
+ { 10, 10, DIFF_NORMAL, 0 },
{ 7, 7, DIFF_HARD, 0 },
- { 10, 10, DIFF_EASY, 0 },
- { 10, 10, DIFF_NORMAL, 0 },
- { 10, 10, DIFF_HARD, 0 },
-#ifndef SLOW_SYSTEM
- { 15, 15, DIFF_EASY, 0 },
- { 15, 15, DIFF_NORMAL, 0 },
- { 15, 15, DIFF_HARD, 0 },
- { 30, 20, DIFF_EASY, 0 },
- { 30, 20, DIFF_NORMAL, 0 },
- { 30, 20, DIFF_HARD, 0 }
+ { 10, 10, DIFF_HARD, 0 },
+ { 10, 10, DIFF_HARD, 1 },
+ { 12, 10, DIFF_HARD, 2 },
+ { 7, 7, DIFF_HARD, 3 },
+ { 9, 9, DIFF_HARD, 4 },
+ { 5, 4, DIFF_HARD, 5 },
+ { 7, 7, DIFF_HARD, 6 },
+ { 5, 5, DIFF_HARD, 7 },
+ { 5, 5, DIFF_HARD, 8 },
+ { 5, 4, DIFF_HARD, 9 },
+ { 5, 4, DIFF_HARD, 10 },
+ { 10, 10, DIFF_HARD, 11 },
+ { 10, 10, DIFF_HARD, 12 }
#endif
};
tmppar = snew(game_params);
*tmppar = presets[i];
*params = tmppar;
- sprintf(buf, "%dx%d %s", tmppar->h, tmppar->w, diffnames[tmppar->diff]);
+ sprintf(buf, "%dx%d %s - %s", tmppar->h, tmppar->w,
+ gridnames[tmppar->type], diffnames[tmppar->diff]);
*name = dupstr(buf);
return TRUE;
static void decode_params(game_params *params, char const *string)
{
params->h = params->w = atoi(string);
- params->rec = 0;
params->diff = DIFF_EASY;
while (*string && isdigit((unsigned char)*string)) string++;
if (*string == 'x') {
params->h = atoi(string);
while (*string && isdigit((unsigned char)*string)) string++;
}
- if (*string == 'r') {
+ if (*string == 't') {
string++;
- params->rec = atoi(string);
+ params->type = atoi(string);
while (*string && isdigit((unsigned char)*string)) string++;
}
if (*string == 'd') {
}
}
-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%d", params->w, params->h);
+ sprintf(str, "%dx%dt%d", params->w, params->h, params->type);
if (full)
- sprintf(str + strlen(str), "r%dd%c", params->rec, diffchars[params->diff]);
+ sprintf(str + strlen(str), "d%c", diffchars[params->diff]);
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];
- ret = snewn(4, config_item);
+ ret = snewn(5, config_item);
ret[0].name = "Width";
ret[0].type = C_STRING;
ret[1].sval = dupstr(buf);
ret[1].ival = 0;
- ret[2].name = "Difficulty";
+ ret[2].name = "Grid type";
ret[2].type = C_CHOICES;
- ret[2].sval = DIFFCONFIG;
- ret[2].ival = params->diff;
+ ret[2].sval = GRID_CONFIGS;
+ ret[2].ival = params->type;
+
+ ret[3].name = "Difficulty";
+ ret[3].type = C_CHOICES;
+ ret[3].sval = DIFFCONFIG;
+ ret[3].ival = params->diff;
- ret[3].name = NULL;
- ret[3].type = C_END;
- ret[3].sval = NULL;
- ret[3].ival = 0;
+ ret[4].name = NULL;
+ ret[4].type = C_END;
+ ret[4].sval = NULL;
+ ret[4].ival = 0;
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);
ret->w = atoi(cfg[0].sval);
ret->h = atoi(cfg[1].sval);
- ret->rec = 0;
- ret->diff = cfg[2].ival;
+ ret->type = cfg[2].ival;
+ ret->diff = cfg[3].ival;
return ret;
}
-static char *validate_params(game_params *params, int full)
+static char *validate_params(const game_params *params, int full)
{
- if (params->w < 4 || params->h < 4)
- return "Width and height must both be at least 4";
- if (params->rec < 0)
- return "Recursion depth can't be negative";
+ if (params->type < 0 || params->type >= NUM_GRID_TYPES)
+ return "Illegal grid type";
+ if (params->w < grid_size_limits[params->type].amin ||
+ params->h < grid_size_limits[params->type].amin)
+ return grid_size_limits[params->type].aerr;
+ if (params->w < grid_size_limits[params->type].omin &&
+ params->h < grid_size_limits[params->type].omin)
+ return grid_size_limits[params->type].oerr;
/*
* This shouldn't be able to happen at all, since decode_params
/* Returns a newly allocated string describing the current puzzle */
static char *state_to_text(const game_state *state)
{
+ grid *g = state->game_grid;
char *retval;
- char *description = snewn(SQUARE_COUNT(state) + 1, char);
+ int num_faces = g->num_faces;
+ char *description = snewn(num_faces + 1, char);
char *dp = description;
int empty_count = 0;
- int i, j;
+ int i;
- FORALL_SQUARES(state, i, j) {
- if (CLUE_AT(state, i, j) < 0) {
+ for (i = 0; i < num_faces; i++) {
+ if (state->clues[i] < 0) {
if (empty_count > 25) {
dp += sprintf(dp, "%c", (int)(empty_count + 'a' - 1));
empty_count = 0;
dp += sprintf(dp, "%c", (int)(empty_count + 'a' - 1));
empty_count = 0;
}
- dp += sprintf(dp, "%c", (int)CLUE2CHAR(CLUE_AT(state, i, j)));
+ dp += sprintf(dp, "%c", (int)CLUE2CHAR(state->clues[i]));
}
}
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;
+ 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') {
+ if ((*desc >= '0' && *desc <= '9') || (*desc >= 'A' && *desc <= 'Z')) {
count++;
continue;
}
return "Unknown character in description";
}
- if (count < SQUARE_COUNT(params))
+ if (count < g->num_faces)
return "Description too short for board size";
- if (count > SQUARE_COUNT(params))
+ if (count > g->num_faces)
return "Description too long for board size";
+ grid_free(g);
+
return NULL;
}
static char *encode_solve_move(const game_state *state)
{
- int len, i, j;
+ int len;
char *ret, *p;
+ int i;
+ int num_edges = state->game_grid->num_edges;
+
/* This is going to return a string representing the moves needed to set
* every line in a grid to be the same as the ones in 'state'. The exact
* length of this string is predictable. */
len = 1; /* Count the 'S' prefix */
- /* Numbers in horizontal lines */
- /* Horizontal lines, x position */
- len += len_0_to_n(state->w) * (state->h + 1);
- /* Horizontal lines, y position */
- len += len_0_to_n(state->h + 1) * (state->w);
- /* Vertical lines, y position */
- len += len_0_to_n(state->h) * (state->w + 1);
- /* Vertical lines, x position */
- len += len_0_to_n(state->w + 1) * (state->h);
- /* For each line we also have two letters and a comma */
- len += 3 * (LINE_COUNT(state));
+ /* Numbers in all lines */
+ len += len_0_to_n(num_edges);
+ /* For each line we also have a letter */
+ len += num_edges;
ret = snewn(len + 1, char);
p = ret;
p += sprintf(p, "S");
- FORALL_HL(state, i, j) {
- switch (RIGHTOF_DOT(state, i, j)) {
- case LINE_YES:
- p += sprintf(p, "%d,%dhy", i, j);
- break;
- case LINE_NO:
- p += sprintf(p, "%d,%dhn", i, j);
- break;
- }
- }
-
- FORALL_VL(state, i, j) {
- switch (BELOW_DOT(state, i, j)) {
- case LINE_YES:
- p += sprintf(p, "%d,%dvy", i, j);
- break;
- case LINE_NO:
- p += sprintf(p, "%d,%dvn", i, j);
- break;
+ for (i = 0; i < num_edges; i++) {
+ switch (state->lines[i]) {
+ case LINE_YES:
+ p += sprintf(p, "%dy", i);
+ break;
+ case LINE_NO:
+ p += sprintf(p, "%dn", i);
+ break;
}
}
return ret;
}
-static game_ui *new_ui(game_state *state)
+static game_ui *new_ui(const game_state *state)
{
return NULL;
}
{
}
-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)
{
}
-#define SIZE(d) ((d) * TILE_SIZE + 2 * BORDER + 1)
-
-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)
{
- struct { int tilesize; } ads, *ds = &ads;
- ads.tilesize = tilesize;
+ int grid_width, grid_height, rendered_width, rendered_height;
+ int g_tilesize;
- *x = SIZE(params->w);
- *y = SIZE(params->h);
+ grid_compute_size(grid_types[params->type], params->w, params->h,
+ &g_tilesize, &grid_width, &grid_height);
+
+ /* multiply first to minimise rounding error on integer division */
+ 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;
- ds->linewidth = max(1,tilesize/16);
}
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]);
ret[COL_FOREGROUND * 3 + 1] = 0.0F;
ret[COL_FOREGROUND * 3 + 2] = 0.0F;
+ /*
+ * We want COL_LINEUNKNOWN to be a yellow which is a bit darker
+ * than the background. (I previously set it to 0.8,0.8,0, but
+ * found that this went badly with the 0.8,0.8,0.8 favoured as a
+ * background by the Java frontend.)
+ */
+ ret[COL_LINEUNKNOWN * 3 + 0] = ret[COL_BACKGROUND * 3 + 0] * 0.9F;
+ ret[COL_LINEUNKNOWN * 3 + 1] = ret[COL_BACKGROUND * 3 + 1] * 0.9F;
+ ret[COL_LINEUNKNOWN * 3 + 2] = 0.0F;
+
ret[COL_HIGHLIGHT * 3 + 0] = 1.0F;
ret[COL_HIGHLIGHT * 3 + 1] = 1.0F;
ret[COL_HIGHLIGHT * 3 + 2] = 1.0F;
ret[COL_MISTAKE * 3 + 1] = 0.0F;
ret[COL_MISTAKE * 3 + 2] = 0.0F;
+ ret[COL_SATISFIED * 3 + 0] = 0.0F;
+ ret[COL_SATISFIED * 3 + 1] = 0.0F;
+ ret[COL_SATISFIED * 3 + 2] = 0.0F;
+
+ /* We want the faint lines to be a bit darker than the background.
+ * Except if the background is pretty dark already; then it ought to be a
+ * bit lighter. Oy vey.
+ */
+ ret[COL_FAINT * 3 + 0] = ret[COL_BACKGROUND * 3 + 0] * 0.9F;
+ ret[COL_FAINT * 3 + 1] = ret[COL_BACKGROUND * 3 + 1] * 0.9F;
+ ret[COL_FAINT * 3 + 2] = ret[COL_BACKGROUND * 3 + 2] * 0.9F;
+
*ncolours = 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;
+ int num_edges = state->game_grid->num_edges;
+ int i;
- ds->tilesize = ds->linewidth = 0;
+ ds->tilesize = 0;
ds->started = 0;
- ds->hl = snewn(HL_COUNT(state), char);
- ds->vl = snewn(VL_COUNT(state), char);
- ds->clue_error = snewn(SQUARE_COUNT(state), char);
+ ds->lines = snewn(num_edges, char);
+ ds->clue_error = snewn(num_faces, char);
+ ds->clue_satisfied = snewn(num_faces, char);
+ ds->textx = snewn(num_faces, int);
+ ds->texty = snewn(num_faces, int);
ds->flashing = 0;
- memset(ds->hl, LINE_UNKNOWN, HL_COUNT(state));
- memset(ds->vl, LINE_UNKNOWN, VL_COUNT(state));
- memset(ds->clue_error, 0, SQUARE_COUNT(state));
+ memset(ds->lines, LINE_UNKNOWN, num_edges);
+ memset(ds->clue_error, 0, num_faces);
+ memset(ds->clue_satisfied, 0, num_faces);
+ for (i = 0; i < num_faces; i++)
+ ds->textx[i] = ds->texty[i] = -1;
return ds;
}
static void game_free_drawstate(drawing *dr, game_drawstate *ds)
{
+ sfree(ds->textx);
+ sfree(ds->texty);
sfree(ds->clue_error);
- sfree(ds->hl);
- sfree(ds->vl);
+ 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 char *game_text_format(game_state *state)
+static int game_can_format_as_text_now(const game_params *params)
{
- int i, j;
- int len;
- char *ret, *rp;
+ if (params->type != 0)
+ return FALSE;
+ return TRUE;
+}
- len = (2 * state->w + 2) * (2 * state->h + 1);
- rp = ret = snewn(len + 1, char);
-
-#define DRAW_HL \
- switch (ABOVE_SQUARE(state, i, j)) { \
- case LINE_YES: \
- rp += sprintf(rp, " -"); \
- break; \
- case LINE_NO: \
- rp += sprintf(rp, " x"); \
- break; \
- case LINE_UNKNOWN: \
- rp += sprintf(rp, " "); \
- break; \
- default: \
- assert(!"Illegal line state for HL"); \
- }
-
-#define DRAW_VL \
- switch (LEFTOF_SQUARE(state, i, j)) { \
- case LINE_YES: \
- rp += sprintf(rp, "|"); \
- break; \
- case LINE_NO: \
- rp += sprintf(rp, "x"); \
- break; \
- case LINE_UNKNOWN: \
- rp += sprintf(rp, " "); \
- break; \
- default: \
- assert(!"Illegal line state for VL"); \
- }
-
- for (j = 0; j < state->h; ++j) {
- for (i = 0; i < state->w; ++i) {
- DRAW_HL;
+static char *game_text_format(const game_state *state)
+{
+ int w, h, W, H;
+ int x, y, i;
+ int cell_size;
+ char *ret;
+ grid *g = state->game_grid;
+ grid_face *f;
+
+ assert(state->grid_type == 0);
+
+ /* Work out the basic size unit */
+ f = g->faces; /* first face */
+ assert(f->order == 4);
+ /* The dots are ordered clockwise, so the two opposite
+ * corners are guaranteed to span the square */
+ cell_size = abs(f->dots[0]->x - f->dots[2]->x);
+
+ w = (g->highest_x - g->lowest_x) / cell_size;
+ h = (g->highest_y - g->lowest_y) / cell_size;
+
+ /* Create a blank "canvas" to "draw" on */
+ W = 2 * w + 2;
+ H = 2 * h + 1;
+ ret = snewn(W * H + 1, char);
+ for (y = 0; y < H; y++) {
+ for (x = 0; x < W-1; x++) {
+ ret[y*W + x] = ' ';
}
- rp += sprintf(rp, " \n");
- for (i = 0; i < state->w; ++i) {
- DRAW_VL;
- rp += sprintf(rp, "%c", (int)CLUE2CHAR(CLUE_AT(state, i, j)));
+ ret[y*W + W-1] = '\n';
+ }
+ ret[H*W] = '\0';
+
+ /* Fill in edge info */
+ for (i = 0; i < g->num_edges; i++) {
+ grid_edge *e = g->edges + i;
+ /* Cell coordinates, from (0,0) to (w-1,h-1) */
+ int x1 = (e->dot1->x - g->lowest_x) / cell_size;
+ int x2 = (e->dot2->x - g->lowest_x) / cell_size;
+ int y1 = (e->dot1->y - g->lowest_y) / cell_size;
+ int y2 = (e->dot2->y - g->lowest_y) / cell_size;
+ /* Midpoint, in canvas coordinates (canvas coordinates are just twice
+ * cell coordinates) */
+ x = x1 + x2;
+ y = y1 + y2;
+ switch (state->lines[i]) {
+ case LINE_YES:
+ ret[y*W + x] = (y1 == y2) ? '-' : '|';
+ break;
+ case LINE_NO:
+ ret[y*W + x] = 'x';
+ break;
+ case LINE_UNKNOWN:
+ break; /* already a space */
+ default:
+ assert(!"Illegal line state");
}
- DRAW_VL;
- rp += sprintf(rp, "\n");
}
- for (i = 0; i < state->w; ++i) {
- DRAW_HL;
+
+ /* Fill in clues */
+ for (i = 0; i < g->num_faces; i++) {
+ int x1, x2, y1, y2;
+
+ f = g->faces + i;
+ assert(f->order == 4);
+ /* Cell coordinates, from (0,0) to (w-1,h-1) */
+ x1 = (f->dots[0]->x - g->lowest_x) / cell_size;
+ x2 = (f->dots[2]->x - g->lowest_x) / cell_size;
+ y1 = (f->dots[0]->y - g->lowest_y) / cell_size;
+ y2 = (f->dots[2]->y - g->lowest_y) / cell_size;
+ /* Midpoint, in canvas coordinates */
+ x = x1 + x2;
+ y = y1 + y2;
+ ret[y*W + x] = CLUE2CHAR(state->clues[i]);
}
- rp += sprintf(rp, " \n");
-
- assert(strlen(ret) == len);
return ret;
}
#ifdef DEBUG_CACHES
static void check_caches(const solver_state* sstate)
{
- int i, j;
+ int i;
const game_state *state = sstate->state;
+ const grid *g = state->game_grid;
- FORALL_DOTS(state, i, j) {
-#if 0
- fprintf(stderr, "dot [%d,%d] y: %d %d n: %d %d\n", i, j,
- dot_order(state, i, j, LINE_YES),
- sstate->dot_yescount[i + (state->w + 1) * j],
- dot_order(state, i, j, LINE_NO),
- sstate->dot_nocount[i + (state->w + 1) * j]);
-#endif
-
- assert(dot_order(state, i, j, LINE_YES) ==
- DOT_YES_COUNT(sstate, i, j));
- assert(dot_order(state, i, j, LINE_NO) ==
- DOT_NO_COUNT(sstate, i, j));
+ for (i = 0; i < g->num_dots; i++) {
+ assert(dot_order(state, i, LINE_YES) == sstate->dot_yes_count[i]);
+ assert(dot_order(state, i, LINE_NO) == sstate->dot_no_count[i]);
}
- FORALL_SQUARES(state, i, j) {
-#if 0
- fprintf(stderr, "square [%d,%d] y: %d %d n: %d %d\n", i, j,
- square_order(state, i, j, LINE_YES),
- sstate->square_yescount[i + state->w * j],
- square_order(state, i, j, LINE_NO),
- sstate->square_nocount[i + state->w * j]);
-#endif
-
- assert(square_order(state, i, j, LINE_YES) ==
- SQUARE_YES_COUNT(sstate, i, j));
- assert(square_order(state, i, j, LINE_NO) ==
- SQUARE_NO_COUNT(sstate, i, j));
+ for (i = 0; i < g->num_faces; i++) {
+ assert(face_order(state, i, LINE_YES) == sstate->face_yes_count[i]);
+ assert(face_order(state, i, LINE_NO) == sstate->face_no_count[i]);
}
}
* Solver utility functions
*/
-static int set_line_bydot(solver_state *sstate, int x, int y, enum direction d,
- enum line_state line_new
+/* Sets the line (with index i) to the new state 'line_new', and updates
+ * the cached counts of any affected faces and dots.
+ * Returns TRUE if this actually changed the line's state. */
+static int solver_set_line(solver_state *sstate, int i,
+ enum line_state line_new
#ifdef SHOW_WORKING
- , const char *reason
+ , const char *reason
#endif
- )
+ )
{
game_state *state = sstate->state;
-
- /* This line borders at most two squares in our board. We figure out the
- * x and y positions of those squares so we can record that their yes or no
- * counts have been changed */
- int sq1_x=-1, sq1_y=-1, sq2_x=-1, sq2_y=-1;
- int otherdot_x=-1, otherdot_y=-1;
-
- int progress = FALSE;
-
-#if 0
- fprintf(stderr, "set_line_bydot [%d,%d], %s, %d\n",
- x, y, DIR2STR(d), line_new);
-#endif
+ grid *g;
+ grid_edge *e;
assert(line_new != LINE_UNKNOWN);
check_caches(sstate);
- switch (d) {
- case LEFT:
- assert(x > 0);
-
- if (LEFTOF_DOT(state, x, y) != line_new) {
- LV_LEFTOF_DOT(state, x, y) = line_new;
-
- otherdot_x = x-1;
- otherdot_y = y;
-
- sq1_x = x-1;
- sq1_y = y-1;
- sq2_x = x-1;
- sq2_y = y;
-
- progress = TRUE;
- }
- break;
- case RIGHT:
- assert(x < state->w);
- if (RIGHTOF_DOT(state, x, y) != line_new) {
- LV_RIGHTOF_DOT(state, x, y) = line_new;
-
- otherdot_x = x+1;
- otherdot_y = y;
-
- sq1_x = x;
- sq1_y = y-1;
- sq2_x = x;
- sq2_y = y;
-
- progress = TRUE;
- }
- break;
- case UP:
- assert(y > 0);
- if (ABOVE_DOT(state, x, y) != line_new) {
- LV_ABOVE_DOT(state, x, y) = line_new;
-
- otherdot_x = x;
- otherdot_y = y-1;
-
- sq1_x = x-1;
- sq1_y = y-1;
- sq2_x = x;
- sq2_y = y-1;
-
- progress = TRUE;
- }
- break;
- case DOWN:
- assert(y < state->h);
- if (BELOW_DOT(state, x, y) != line_new) {
- LV_BELOW_DOT(state, x, y) = line_new;
-
- otherdot_x = x;
- otherdot_y = y+1;
-
- sq1_x = x-1;
- sq1_y = y;
- sq2_x = x;
- sq2_y = y;
-
- progress = TRUE;
- }
- break;
+ if (state->lines[i] == line_new) {
+ return FALSE; /* nothing changed */
}
-
- if (!progress)
- return progress;
+ state->lines[i] = line_new;
#ifdef SHOW_WORKING
- fprintf(stderr, "set line [%d,%d] -> [%d,%d] to %s (%s)\n",
- x, y, otherdot_x, otherdot_y, line_new == LINE_YES ? "YES" : "NO",
+ fprintf(stderr, "solver: set line [%d] to %s (%s)\n",
+ i, line_new == LINE_YES ? "YES" : "NO",
reason);
#endif
- /* Above we updated the cache for the dot that the line in question reaches
- * from the dot we've been told about. Here we update that for the dot
- * named in our arguments. */
+ g = state->game_grid;
+ e = g->edges + i;
+
+ /* Update the cache for both dots and both faces affected by this. */
if (line_new == LINE_YES) {
- if (sq1_x >= 0 && sq1_y >= 0)
- ++SQUARE_YES_COUNT(sstate, sq1_x, sq1_y);
- if (sq2_x < state->w && sq2_y < state->h)
- ++SQUARE_YES_COUNT(sstate, sq2_x, sq2_y);
- ++DOT_YES_COUNT(sstate, x, y);
- ++DOT_YES_COUNT(sstate, otherdot_x, otherdot_y);
+ sstate->dot_yes_count[e->dot1 - g->dots]++;
+ sstate->dot_yes_count[e->dot2 - g->dots]++;
+ if (e->face1) {
+ sstate->face_yes_count[e->face1 - g->faces]++;
+ }
+ if (e->face2) {
+ sstate->face_yes_count[e->face2 - g->faces]++;
+ }
} else {
- if (sq1_x >= 0 && sq1_y >= 0)
- ++SQUARE_NO_COUNT(sstate, sq1_x, sq1_y);
- if (sq2_x < state->w && sq2_y < state->h)
- ++SQUARE_NO_COUNT(sstate, sq2_x, sq2_y);
- ++DOT_NO_COUNT(sstate, x, y);
- ++DOT_NO_COUNT(sstate, otherdot_x, otherdot_y);
+ sstate->dot_no_count[e->dot1 - g->dots]++;
+ sstate->dot_no_count[e->dot2 - g->dots]++;
+ if (e->face1) {
+ sstate->face_no_count[e->face1 - g->faces]++;
+ }
+ if (e->face2) {
+ sstate->face_no_count[e->face2 - g->faces]++;
+ }
}
-
+
check_caches(sstate);
- return progress;
+ return TRUE;
}
#ifdef SHOW_WORKING
-#define set_line_bydot(a, b, c, d, e) \
- set_line_bydot(a, b, c, d, e, __FUNCTION__)
+#define solver_set_line(a, b, c) \
+ solver_set_line(a, b, c, __FUNCTION__)
#endif
/*
* Returns TRUE if the dots were already linked, ie if they are part of a
* closed loop, and false otherwise.
*/
-static int merge_dots(solver_state *sstate, int x1, int y1, int x2, int y2)
+static int merge_dots(solver_state *sstate, int edge_index)
{
int i, j, len;
+ grid *g = sstate->state->game_grid;
+ grid_edge *e = g->edges + edge_index;
- i = y1 * (sstate->state->w + 1) + x1;
- j = y2 * (sstate->state->w + 1) + x2;
+ i = e->dot1 - g->dots;
+ j = e->dot2 - g->dots;
i = dsf_canonify(sstate->dotdsf, i);
j = dsf_canonify(sstate->dotdsf, j);
}
}
-/* Seriously, these should be functions */
-
-#define LINEDSF_INDEX(state, x, y, d) \
- ((d == UP) ? ((y-1) * (state->w + 1) + x) : \
- (d == DOWN) ? ((y) * (state->w + 1) + x) : \
- (d == LEFT) ? ((y) * (state->w) + x-1 + VL_COUNT(state)) : \
- (d == RIGHT) ? ((y) * (state->w) + x + VL_COUNT(state)) : \
- (assert(!"bad direction value"), 0))
-
-static void linedsf_deindex(const game_state *state, int i,
- int *px, int *py, enum direction *pd)
-{
- int i_mod;
- if (i < VL_COUNT(state)) {
- *(pd) = DOWN;
- *(px) = (i) % (state->w+1);
- *(py) = (i) / (state->w+1);
- } else {
- i_mod = i - VL_COUNT(state);
- *(pd) = RIGHT;
- *(px) = (i_mod) % (state->w);
- *(py) = (i_mod) / (state->w);
- }
-}
-
/* Merge two lines because the solver has deduced that they must be either
* identical or opposite. Returns TRUE if this is new information, otherwise
* FALSE. */
-static int merge_lines(solver_state *sstate,
- int x1, int y1, enum direction d1,
- int x2, int y2, enum direction d2,
- int inverse
+static int merge_lines(solver_state *sstate, int i, int j, int inverse
#ifdef SHOW_WORKING
, const char *reason
#endif
- )
+ )
{
- int i, j, inv_tmp;
+ int inv_tmp;
- i = LINEDSF_INDEX(sstate->state, x1, y1, d1);
- j = LINEDSF_INDEX(sstate->state, x2, y2, d2);
+ assert(i < sstate->state->game_grid->num_edges);
+ assert(j < sstate->state->game_grid->num_edges);
- assert(i < LINE_COUNT(sstate->state));
- assert(j < LINE_COUNT(sstate->state));
-
- i = edsf_canonify(sstate->hard->linedsf, i, &inv_tmp);
+ i = edsf_canonify(sstate->linedsf, i, &inv_tmp);
inverse ^= inv_tmp;
- j = edsf_canonify(sstate->hard->linedsf, j, &inv_tmp);
+ j = edsf_canonify(sstate->linedsf, j, &inv_tmp);
inverse ^= inv_tmp;
- edsf_merge(sstate->hard->linedsf, i, j, inverse);
+ edsf_merge(sstate->linedsf, i, j, inverse);
#ifdef SHOW_WORKING
if (i != j) {
- fprintf(stderr, "%s [%d,%d,%s] [%d,%d,%s] %s(%s)\n",
- __FUNCTION__,
- x1, y1, DIR2STR(d1),
- x2, y2, DIR2STR(d2),
+ fprintf(stderr, "%s [%d] [%d] %s(%s)\n",
+ __FUNCTION__, i, j,
inverse ? "inverse " : "", reason);
}
#endif
}
#ifdef SHOW_WORKING
-#define merge_lines(a, b, c, d, e, f, g, h) \
- merge_lines(a, b, c, d, e, f, g, h, __FUNCTION__)
-#endif
-
-/* Return 0 if the given lines are not in the same equivalence class, 1 if they
- * are known identical, or 2 if they are known opposite */
-#if 0
-static int lines_related(solver_state *sstate,
- int x1, int y1, enum direction d1,
- int x2, int y2, enum direction d2)
-{
- int i, j, inv1, inv2;
-
- i = LINEDSF_INDEX(sstate->state, x1, y1, d1);
- j = LINEDSF_INDEX(sstate->state, x2, y2, d2);
-
- i = edsf_canonify(sstate->hard->linedsf, i, &inv1);
- j = edsf_canonify(sstate->hard->linedsf, j, &inv2);
-
- if (i == j)
- return (inv1 == inv2) ? 1 : 2;
- else
- return 0;
-}
+#define merge_lines(a, b, c, d) \
+ merge_lines(a, b, c, d, __FUNCTION__)
#endif
/* Count the number of lines of a particular type currently going into the
- * given dot. Lines going off the edge of the board are assumed fixed no. */
-static int dot_order(const game_state* state, int i, int j, char line_type)
+ * given dot. */
+static int dot_order(const game_state* state, int dot, char line_type)
{
int n = 0;
+ grid *g = state->game_grid;
+ grid_dot *d = g->dots + dot;
+ int i;
- if (i > 0) {
- if (line_type == LV_LEFTOF_DOT(state, i, j))
- ++n;
- } else {
- if (line_type == LINE_NO)
- ++n;
- }
- if (i < state->w) {
- if (line_type == LV_RIGHTOF_DOT(state, i, j))
- ++n;
- } else {
- if (line_type == LINE_NO)
- ++n;
- }
- if (j > 0) {
- if (line_type == LV_ABOVE_DOT(state, i, j))
- ++n;
- } else {
- if (line_type == LINE_NO)
- ++n;
- }
- if (j < state->h) {
- if (line_type == LV_BELOW_DOT(state, i, j))
- ++n;
- } else {
- if (line_type == LINE_NO)
+ for (i = 0; i < d->order; i++) {
+ grid_edge *e = d->edges[i];
+ if (state->lines[e - g->edges] == line_type)
++n;
}
-
return n;
}
/* Count the number of lines of a particular type currently surrounding the
- * given square */
-static int square_order(const game_state* state, int i, int j, char line_type)
+ * given face */
+static int face_order(const game_state* state, int face, char line_type)
{
int n = 0;
+ grid *g = state->game_grid;
+ grid_face *f = g->faces + face;
+ int i;
- if (ABOVE_SQUARE(state, i, j) == line_type)
- ++n;
- if (BELOW_SQUARE(state, i, j) == line_type)
- ++n;
- if (LEFTOF_SQUARE(state, i, j) == line_type)
- ++n;
- if (RIGHTOF_SQUARE(state, i, j) == line_type)
- ++n;
-
+ for (i = 0; i < f->order; i++) {
+ grid_edge *e = f->edges[i];
+ if (state->lines[e - g->edges] == line_type)
+ ++n;
+ }
return n;
}
-/* Set all lines bordering a dot of type old_type to type new_type
+/* Set all lines bordering a dot of type old_type to type new_type
* Return value tells caller whether this function actually did anything */
-static int dot_setall(solver_state *sstate, int i, int j,
- char old_type, char new_type)
+static int dot_setall(solver_state *sstate, int dot,
+ char old_type, char new_type)
{
int retval = FALSE, r;
game_state *state = sstate->state;
-
+ grid *g;
+ grid_dot *d;
+ int i;
+
if (old_type == new_type)
return FALSE;
- if (i > 0 && LEFTOF_DOT(state, i, j) == old_type) {
- r = set_line_bydot(sstate, i, j, LEFT, new_type);
- assert(r == TRUE);
- retval = TRUE;
- }
-
- if (i < state->w && RIGHTOF_DOT(state, i, j) == old_type) {
- r = set_line_bydot(sstate, i, j, RIGHT, new_type);
- assert(r == TRUE);
- retval = TRUE;
- }
-
- if (j > 0 && ABOVE_DOT(state, i, j) == old_type) {
- r = set_line_bydot(sstate, i, j, UP, new_type);
- assert(r == TRUE);
- retval = TRUE;
- }
+ g = state->game_grid;
+ d = g->dots + dot;
- if (j < state->h && BELOW_DOT(state, i, j) == old_type) {
- r = set_line_bydot(sstate, i, j, DOWN, new_type);
- assert(r == TRUE);
- retval = TRUE;
+ for (i = 0; i < d->order; i++) {
+ int line_index = d->edges[i] - g->edges;
+ if (state->lines[line_index] == old_type) {
+ r = solver_set_line(sstate, line_index, new_type);
+ assert(r == TRUE);
+ retval = TRUE;
+ }
}
-
return retval;
}
-/* Set all lines bordering a square of type old_type to type new_type */
-static int square_setall(solver_state *sstate, int i, int j,
- char old_type, char new_type)
+/* Set all lines bordering a face of type old_type to type new_type */
+static int face_setall(solver_state *sstate, int face,
+ char old_type, char new_type)
{
- int r = FALSE;
+ int retval = FALSE, r;
game_state *state = sstate->state;
+ grid *g;
+ grid_face *f;
+ int i;
-#if 0
- fprintf(stderr, "square_setall [%d,%d] from %d to %d\n", i, j,
- old_type, new_type);
-#endif
- if (ABOVE_SQUARE(state, i, j) == old_type) {
- r = set_line_bydot(sstate, i, j, RIGHT, new_type);
- assert(r == TRUE);
- }
- if (BELOW_SQUARE(state, i, j) == old_type) {
- r = set_line_bydot(sstate, i, j+1, RIGHT, new_type);
- assert(r == TRUE);
- }
- if (LEFTOF_SQUARE(state, i, j) == old_type) {
- r = set_line_bydot(sstate, i, j, DOWN, new_type);
- assert(r == TRUE);
- }
- if (RIGHTOF_SQUARE(state, i, j) == old_type) {
- r = set_line_bydot(sstate, i+1, j, DOWN, new_type);
- assert(r == TRUE);
- }
+ if (old_type == new_type)
+ return FALSE;
- return r;
+ g = state->game_grid;
+ f = g->faces + face;
+
+ for (i = 0; i < f->order; i++) {
+ int line_index = f->edges[i] - g->edges;
+ if (state->lines[line_index] == old_type) {
+ r = solver_set_line(sstate, line_index, new_type);
+ assert(r == TRUE);
+ retval = TRUE;
+ }
+ }
+ return retval;
}
/* ----------------------------------------------------------------------
* Loop generation and clue removal
*/
-/* We're going to store a list of current candidate squares for lighting.
- * Each square gets a 'score', which tells us how adding that square right
- * now would affect the length of the solution loop. We're trying to
- * maximise that quantity so will bias our random selection of squares to
- * light towards those with high scores */
-struct square {
- int score;
- unsigned long random;
- int x, y;
-};
-
-static int get_square_cmpfn(void *v1, void *v2)
+static void add_full_clues(game_state *state, random_state *rs)
{
- struct square *s1 = v1;
- struct square *s2 = v2;
- int r;
-
- r = s1->x - s2->x;
- if (r)
- return r;
-
- r = s1->y - s2->y;
- if (r)
- return r;
+ signed char *clues = state->clues;
+ grid *g = state->game_grid;
+ char *board = snewn(g->num_faces, char);
+ int i;
- return 0;
+ 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, g->num_faces);
+ for (i = 0; i < g->num_edges; i++) {
+ grid_edge *e = g->edges + i;
+ grid_face *f1 = e->face1;
+ grid_face *f2 = e->face2;
+ enum face_colour c1 = FACE_COLOUR(f1);
+ enum face_colour c2 = FACE_COLOUR(f2);
+ assert(c1 != FACE_GREY);
+ assert(c2 != FACE_GREY);
+ if (c1 != c2) {
+ if (f1) clues[f1 - g->faces]++;
+ if (f2) clues[f2 - g->faces]++;
+ }
+ }
+ sfree(board);
}
-static int square_sort_cmpfn(void *v1, void *v2)
-{
- struct square *s1 = v1;
- struct square *s2 = v2;
- int r;
- r = s2->score - s1->score;
- if (r) {
- return r;
- }
+static int game_has_unique_soln(const game_state *state, int diff)
+{
+ int ret;
+ solver_state *sstate_new;
+ solver_state *sstate = new_solver_state((game_state *)state, diff);
- if (s1->random < s2->random)
- return -1;
- else if (s1->random > s2->random)
- return 1;
+ sstate_new = solve_game_rec(sstate);
- /*
- * It's _just_ possible that two squares might have been given
- * the same random value. In that situation, fall back to
- * comparing based on the coordinates. This introduces a tiny
- * directional bias, but not a significant one.
- */
- return get_square_cmpfn(v1, v2);
-}
+ assert(sstate_new->solver_status != SOLVER_MISTAKE);
+ ret = (sstate_new->solver_status == SOLVER_SOLVED);
-enum { SQUARE_LIT, SQUARE_UNLIT };
+ free_solver_state(sstate_new);
+ free_solver_state(sstate);
-#define SQUARE_STATE(i, j) \
- ( LEGAL_SQUARE(state, i, j) ? \
- LV_SQUARE_STATE(i,j) : \
- SQUARE_UNLIT )
+ return ret;
+}
-#define LV_SQUARE_STATE(i, j) board[SQUARE_INDEX(state, i, j)]
-/* Generate a new complete set of clues for the given game_state (respecting
- * the dimensions provided by said game_state) */
-static void add_full_clues(game_state *state, random_state *rs)
+/* Remove clues one at a time at random. */
+static game_state *remove_clues(game_state *state, random_state *rs,
+ int diff)
{
- char *clues;
- char *board;
- int i, j, a, b, c;
- int board_area = SQUARE_COUNT(state);
- int t;
-
- struct square *square, *tmpsquare, *sq;
- struct square square_pos;
-
- /* These will contain exactly the same information, sorted into different
- * orders */
- tree234 *lightable_squares_sorted, *lightable_squares_gettable;
-
-#define SQUARE_REACHABLE(i,j) \
- (t = (SQUARE_STATE(i-1, j) == SQUARE_LIT || \
- SQUARE_STATE(i+1, j) == SQUARE_LIT || \
- SQUARE_STATE(i, j-1) == SQUARE_LIT || \
- SQUARE_STATE(i, j+1) == SQUARE_LIT), \
- t)
-
- /* One situation in which we may not light a square is if that'll leave one
- * square above/below and one left/right of us unlit, separated by a lit
- * square diagnonal from us */
-#define SQUARE_DIAGONAL_VIOLATION(i, j, h, v) \
- (t = (SQUARE_STATE((i)+(h), (j)) == SQUARE_UNLIT && \
- SQUARE_STATE((i), (j)+(v)) == SQUARE_UNLIT && \
- SQUARE_STATE((i)+(h), (j)+(v)) == SQUARE_LIT), \
- t)
-
- /* We also may not light a square if it will form a loop of lit squares
- * around some unlit squares, as then the game soln won't have a single
- * loop */
-#define SQUARE_LOOP_VIOLATION(i, j, lit1, lit2) \
- (SQUARE_STATE((i)+1, (j)) == lit1 && \
- SQUARE_STATE((i)-1, (j)) == lit1 && \
- SQUARE_STATE((i), (j)+1) == lit2 && \
- SQUARE_STATE((i), (j)-1) == lit2)
-
-#define CAN_LIGHT_SQUARE(i, j) \
- (SQUARE_REACHABLE(i, j) && \
- !SQUARE_DIAGONAL_VIOLATION(i, j, -1, -1) && \
- !SQUARE_DIAGONAL_VIOLATION(i, j, +1, -1) && \
- !SQUARE_DIAGONAL_VIOLATION(i, j, -1, +1) && \
- !SQUARE_DIAGONAL_VIOLATION(i, j, +1, +1) && \
- !SQUARE_LOOP_VIOLATION(i, j, SQUARE_LIT, SQUARE_UNLIT) && \
- !SQUARE_LOOP_VIOLATION(i, j, SQUARE_UNLIT, SQUARE_LIT))
-
-#define IS_LIGHTING_CANDIDATE(i, j) \
- (SQUARE_STATE(i, j) == SQUARE_UNLIT && \
- CAN_LIGHT_SQUARE(i,j))
-
- /* The 'score' of a square reflects its current desirability for selection
- * as the next square to light. We want to encourage moving into uncharted
- * areas so we give scores according to how many of the square's neighbours
- * are currently unlit. */
-
- /* UNLIT SCORE
- * 3 2
- * 2 0
- * 1 -2
- */
-#define SQUARE_SCORE(i,j) \
- (2*((SQUARE_STATE(i-1, j) == SQUARE_UNLIT) + \
- (SQUARE_STATE(i+1, j) == SQUARE_UNLIT) + \
- (SQUARE_STATE(i, j-1) == SQUARE_UNLIT) + \
- (SQUARE_STATE(i, j+1) == SQUARE_UNLIT)) - 4)
-
- /* When a square gets lit, this defines how far away from that square we
- * need to go recomputing scores */
-#define SCORE_DISTANCE 1
-
- board = snewn(board_area, char);
- clues = state->clues;
-
- /* Make a board */
- memset(board, SQUARE_UNLIT, board_area);
-
- /* Seed the board with a single lit square near the middle */
- i = state->w / 2;
- j = state->h / 2;
- if (state->w & 1 && random_bits(rs, 1))
- ++i;
- if (state->h & 1 && random_bits(rs, 1))
- ++j;
-
- LV_SQUARE_STATE(i, j) = SQUARE_LIT;
-
- /* We need a way of favouring squares that will increase our loopiness.
- * We do this by maintaining a list of all candidate squares sorted by
- * their score and choose randomly from that with appropriate skew.
- * In order to avoid consistently biasing towards particular squares, 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 square 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 squares in
- * any one run but that doesn't actually matter. */
-
- lightable_squares_sorted = newtree234(square_sort_cmpfn);
- lightable_squares_gettable = newtree234(get_square_cmpfn);
-#define ADD_SQUARE(s) \
- do { \
- sq = add234(lightable_squares_sorted, s); \
- assert(sq == s); \
- sq = add234(lightable_squares_gettable, s); \
- assert(sq == s); \
- } while (0)
-
-#define REMOVE_SQUARE(s) \
- do { \
- sq = del234(lightable_squares_sorted, s); \
- assert(sq); \
- sq = del234(lightable_squares_gettable, s); \
- assert(sq); \
- } while (0)
-
-#define HANDLE_DIR(a, b) \
- square = snew(struct square); \
- square->x = (i)+(a); \
- square->y = (j)+(b); \
- square->score = 2; \
- square->random = random_bits(rs, 31); \
- ADD_SQUARE(square);
- HANDLE_DIR(-1, 0);
- HANDLE_DIR( 1, 0);
- HANDLE_DIR( 0,-1);
- HANDLE_DIR( 0, 1);
-#undef HANDLE_DIR
-
- /* Light squares one at a time until the board is interesting enough */
- while (TRUE)
- {
- /* We have count234(lightable_squares) possibilities, and in
- * lightable_squares_sorted they are sorted with the most desirable
- * first. */
- c = count234(lightable_squares_sorted);
- if (c == 0)
- break;
- assert(c == count234(lightable_squares_gettable));
-
- /* Check that the best square available is any good */
- square = (struct square *)index234(lightable_squares_sorted, 0);
- assert(square);
-
- /*
- * We never want to _decrease_ the loop's perimeter. Making
- * moves that leave the perimeter the same is occasionally
- * useful: if it were _never_ done then the user would be
- * able to deduce illicitly that any degree-zero vertex was
- * on the outside of the loop. So we do it sometimes but
- * not always.
- */
- if (square->score < 0 || (square->score == 0 &&
- random_upto(rs, 2) == 0)) {
- break;
- }
-
- assert(square->score == SQUARE_SCORE(square->x, square->y));
- assert(SQUARE_STATE(square->x, square->y) == SQUARE_UNLIT);
- assert(square->x >= 0 && square->x < state->w);
- assert(square->y >= 0 && square->y < state->h);
-
- /* Update data structures */
- LV_SQUARE_STATE(square->x, square->y) = SQUARE_LIT;
- REMOVE_SQUARE(square);
-
- /* We might have changed the score of any squares up to 2 units away in
- * any direction */
- for (b = -SCORE_DISTANCE; b <= SCORE_DISTANCE; b++) {
- for (a = -SCORE_DISTANCE; a <= SCORE_DISTANCE; a++) {
- if (!a && !b)
- continue;
- square_pos.x = square->x + a;
- square_pos.y = square->y + b;
- if (square_pos.x < 0 || square_pos.x >= state->w ||
- square_pos.y < 0 || square_pos.y >= state->h) {
- continue;
- }
- tmpsquare = find234(lightable_squares_gettable, &square_pos,
- NULL);
- if (tmpsquare) {
- assert(tmpsquare->x == square_pos.x);
- assert(tmpsquare->y == square_pos.y);
- assert(SQUARE_STATE(tmpsquare->x, tmpsquare->y) ==
- SQUARE_UNLIT);
- REMOVE_SQUARE(tmpsquare);
- } else {
- tmpsquare = snew(struct square);
- tmpsquare->x = square_pos.x;
- tmpsquare->y = square_pos.y;
- tmpsquare->random = random_bits(rs, 31);
- }
- tmpsquare->score = SQUARE_SCORE(tmpsquare->x, tmpsquare->y);
-
- if (IS_LIGHTING_CANDIDATE(tmpsquare->x, tmpsquare->y)) {
- ADD_SQUARE(tmpsquare);
- } else {
- sfree(tmpsquare);
- }
- }
- }
- sfree(square);
- }
-
- /* Clean up */
- while ((square = delpos234(lightable_squares_gettable, 0)) != NULL)
- sfree(square);
- freetree234(lightable_squares_gettable);
- freetree234(lightable_squares_sorted);
-
- /* Copy out all the clues */
- FORALL_SQUARES(state, i, j) {
- c = SQUARE_STATE(i, j);
- LV_CLUE_AT(state, i, j) = 0;
- if (SQUARE_STATE(i-1, j) != c) ++LV_CLUE_AT(state, i, j);
- if (SQUARE_STATE(i+1, j) != c) ++LV_CLUE_AT(state, i, j);
- if (SQUARE_STATE(i, j-1) != c) ++LV_CLUE_AT(state, i, j);
- if (SQUARE_STATE(i, j+1) != c) ++LV_CLUE_AT(state, i, j);
- }
-
- sfree(board);
-}
-
-static int game_has_unique_soln(const game_state *state, int diff)
-{
- int ret;
- solver_state *sstate_new;
- solver_state *sstate = new_solver_state((game_state *)state, diff);
-
- sstate_new = solve_game_rec(sstate, diff);
-
- assert(sstate_new->solver_status != SOLVER_MISTAKE);
- ret = (sstate_new->solver_status == SOLVER_SOLVED);
-
- free_solver_state(sstate_new);
- free_solver_state(sstate);
-
- return ret;
-}
-
-/* Remove clues one at a time at random. */
-static game_state *remove_clues(game_state *state, random_state *rs,
- int diff)
-{
- int *square_list, squares;
- game_state *ret = dup_game(state), *saved_ret;
- int n;
-#ifdef SHOW_WORKING
- char *desc;
-#endif
+ int *face_list;
+ int num_faces = state->game_grid->num_faces;
+ game_state *ret = dup_game(state), *saved_ret;
+ int n;
/* We need to remove some clues. We'll do this by forming a list of all
* available clues, shuffling it, then going along one at a
* time clearing each clue in turn for which doing so doesn't render the
* board unsolvable. */
- squares = state->w * state->h;
- square_list = snewn(squares, int);
- for (n = 0; n < squares; ++n) {
- square_list[n] = n;
+ face_list = snewn(num_faces, int);
+ for (n = 0; n < num_faces; ++n) {
+ face_list[n] = n;
}
- shuffle(square_list, squares, sizeof(int), rs);
-
- for (n = 0; n < squares; ++n) {
- saved_ret = dup_game(ret);
- LV_CLUE_AT(ret, square_list[n] % state->w,
- square_list[n] / state->w) = -1;
+ shuffle(face_list, num_faces, sizeof(int), rs);
-#ifdef SHOW_WORKING
- desc = state_to_text(ret);
- fprintf(stderr, "%dx%d:%s\n", state->w, state->h, desc);
- sfree(desc);
-#endif
+ for (n = 0; n < num_faces; ++n) {
+ saved_ret = dup_game(ret);
+ ret->clues[face_list[n]] = -1;
if (game_has_unique_soln(ret, diff)) {
free_game(saved_ret);
ret = saved_ret;
}
}
- sfree(square_list);
+ sfree(face_list);
return ret;
}
-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;
- game_state *state = snew(game_state), *state_new;
+ char *retval, *game_desc, *grid_desc;
+ grid *g;
+ game_state *state = snew(game_state);
+ game_state *state_new;
- state->h = params->h;
- state->w = params->w;
+ 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(SQUARE_COUNT(params), char);
- state->hl = snewn(HL_COUNT(params), char);
- state->vl = snewn(VL_COUNT(params), char);
+ 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;
-newboard_please:
- memset(state->hl, LINE_UNKNOWN, HL_COUNT(params));
- memset(state->vl, LINE_UNKNOWN, VL_COUNT(params));
+ state->grid_type = params->type;
+
+ newboard_please:
+
+ memset(state->lines, LINE_UNKNOWN, g->num_edges);
+ memset(state->line_errors, 0, g->num_edges);
state->solved = state->cheated = FALSE;
- state->recursion_depth = params->rec;
/* Get a new random solvable board with all its clues filled in. Yes, this
* can loop for ever if the params are suitably unfavourable, but
* preventing games smaller than 4x4 seems to stop this happening */
-
do {
add_full_clues(state, rs);
} while (!game_has_unique_soln(state, params->diff));
free_game(state);
state = state_new;
+
if (params->diff > 0 && game_has_unique_soln(state, params->diff-1)) {
#ifdef SHOW_WORKING
fprintf(stderr, "Rejecting board, it is too easy\n");
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,j;
+ int i;
game_state *state = snew(game_state);
int empties_to_make = 0;
- int n;
- const char *dp = desc;
+ int n,n2;
+ const char *dp;
+ char *grid_desc;
+ grid *g;
+ int num_faces, num_edges;
- state->recursion_depth = 0; /* XXX pending removal, probably */
-
- state->h = params->h;
- state->w = params->w;
+ grid_desc = extract_grid_desc(&desc);
+ state->game_grid = g = loopy_generate_grid(params, grid_desc);
+ if (grid_desc) sfree(grid_desc);
- state->clues = snewn(SQUARE_COUNT(params), char);
- state->hl = snewn(HL_COUNT(params), char);
- state->vl = snewn(VL_COUNT(params), char);
+ 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;
- FORALL_SQUARES(params, i, j) {
+ state->grid_type = params->type;
+
+ for (i = 0; i < num_faces; i++) {
if (empties_to_make) {
empties_to_make--;
- LV_CLUE_AT(state, i, j) = -1;
+ state->clues[i] = -1;
continue;
}
assert(*dp);
n = *dp - '0';
+ n2 = *dp - 'A' + 10;
if (n >= 0 && n < 10) {
- LV_CLUE_AT(state, i, j) = n;
+ state->clues[i] = n;
+ } else if (n2 >= 10 && n2 < 36) {
+ state->clues[i] = n2;
} else {
n = *dp - 'a' + 1;
assert(n > 0);
- LV_CLUE_AT(state, i, j) = -1;
+ state->clues[i] = -1;
empties_to_make = n - 1;
}
++dp;
}
- memset(state->hl, LINE_UNKNOWN, HL_COUNT(params));
- memset(state->vl, LINE_UNKNOWN, VL_COUNT(params));
-
+ memset(state->lines, LINE_UNKNOWN, num_edges);
+ memset(state->line_errors, 0, num_edges);
return state;
}
-enum { LOOP_NONE=0, LOOP_SOLN, LOOP_NOT_SOLN };
+/* Calculates the line_errors data, and checks if the current state is a
+ * solution */
+static int check_completion(game_state *state)
+{
+ grid *g = state->game_grid;
+ 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);
+
+ /*
+ * 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.
+ *
+ * - 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.)
+ *
+ * - Any component that contains such a vertex is now excluded
+ * from further consideration, because it already has a
+ * highlight.
+ *
+ * - 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.
+ *
+ * - 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).
+ *
+ * - 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.
+ */
+
+ dsf = snew_dsf(g->num_dots);
+
+ /* 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);
+ }
+ }
+
+ /* 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 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)) {
+ /* violation, so mark all YES edges as errors */
+ grid_dot *d = g->dots + i;
+ int j;
+ for (j = 0; j < d->order; j++) {
+ int e = d->edges[j] - g->edges;
+ 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;
+ }
+ }
+ }
+ 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;
+}
/* ----------------------------------------------------------------------
* Solver logic
* Easy Mode
* Just implement the rules of the game.
*
- * Normal Mode
- * For each pair of lines through each dot we store a bit for whether
- * at least one of them is on and whether at most one is on. (If we know
- * both or neither is on that's already stored more directly.) That's six
- * bits per dot. Bit number n represents the lines shown in dline_desc.
+ * Normal and Tricky Modes
+ * For each (adjacent) pair of lines through each dot we store a bit for
+ * whether at least one of them is on and whether at most one is on. (If we
+ * know both or neither is on that's already stored more directly.)
*
* Advanced Mode
* Use edsf data structure to make equivalence classes of lines that are
* known identical to or opposite to one another.
*/
-/* The order the following are defined in is very important, see below.
- * The last two fields may seem non-obvious: they specify that when talking
- * about a square the dx and dy offsets should be added to the square coords to
- * get to the right dot. Where dx and dy are -1 this means that the dline
- * doesn't make sense for a square. */
-/* XXX can this be done with a struct instead? */
-#define DLINES \
- DLINE(DLINE_UD, UP, DOWN, -1, -1) \
- DLINE(DLINE_LR, LEFT, RIGHT, -1, -1) \
- DLINE(DLINE_UR, UP, RIGHT, 0, 1) \
- DLINE(DLINE_DL, DOWN, LEFT, 1, 0) \
- DLINE(DLINE_UL, UP, LEFT, 1, 1) \
- DLINE(DLINE_DR, DOWN, RIGHT, 0, 0)
-
-#define OPP_DLINE(dline_desc) ((dline_desc) ^ 1)
-
-enum dline_desc {
-#define DLINE(desc, dir1, dir2, dx, dy) \
- desc,
- DLINES
-#undef DLINE
-};
-
-struct dline {
- enum dline_desc desc;
- enum direction dir1, dir2;
- int dx, dy;
-};
-
-const static struct dline dlines[] = {
-#define DLINE(desc, dir1, dir2, dx, dy) \
- { desc, dir1, dir2, dx, dy },
- DLINES
-#undef DLINE
-};
-
-#define FORALL_DOT_DLINES(dl_iter) \
- for (dl_iter = 0; dl_iter < lenof(dlines); ++dl_iter)
-
-#define FORALL_SQUARE_DLINES(dl_iter) \
- for (dl_iter = 2; dl_iter < lenof(dlines); ++dl_iter)
-
-#define DL2STR(d) \
- ((d==DLINE_UD) ? "DLINE_UD": \
- (d==DLINE_LR) ? "DLINE_LR": \
- (d==DLINE_UR) ? "DLINE_UR": \
- (d==DLINE_DL) ? "DLINE_DL": \
- (d==DLINE_UL) ? "DLINE_UL": \
- (d==DLINE_DR) ? "DLINE_DR": \
- "oops")
-
-#define CHECK_DLINE_SENSIBLE(d) assert(dlines[(d)].dx != -1 && dlines[(d)].dy != -1)
-
-/* This will fail an assertion if the directions handed to it are the same, as
- * no dline corresponds to that */
-static enum dline_desc dline_desc_from_dirs(enum direction dir1,
- enum direction dir2)
-{
- int i;
- assert (dir1 != dir2);
-
- for (i = 0; i < lenof(dlines); ++i) {
- if ((dir1 == dlines[i].dir1 && dir2 == dlines[i].dir2) ||
- (dir1 == dlines[i].dir2 && dir2 == dlines[i].dir1)) {
- return dlines[i].desc;
- }
- }
+/* DLines:
+ * For general grids, we consider "dlines" to be pairs of lines joined
+ * at a dot. The lines must be adjacent around the dot, so we can think of
+ * a dline as being a dot+face combination. Or, a dot+edge combination where
+ * the second edge is taken to be the next clockwise edge from the dot.
+ * Original loopy code didn't have this extra restriction of the lines being
+ * adjacent. From my tests with square grids, this extra restriction seems to
+ * take little, if anything, away from the quality of the puzzles.
+ * A dline can be uniquely identified by an edge/dot combination, given that
+ * a dline-pair always goes clockwise around its common dot. The edge/dot
+ * combination can be represented by an edge/bool combination - if bool is
+ * TRUE, use edge->dot1 else use edge->dot2. So the total number of dlines is
+ * exactly twice the number of edges in the grid - although the dlines
+ * spanning the infinite face are not all that useful to the solver.
+ * Note that, by convention, a dline goes clockwise around its common dot,
+ * which means the dline goes anti-clockwise around its common face.
+ */
- assert(!"dline not found");
- return DLINE_UD; /* placate compiler */
-}
+/* Helper functions for obtaining an index into an array of dlines, given
+ * various information. We assume the grid layout conventions about how
+ * the various lists are interleaved - see grid_make_consistent() for
+ * details. */
-/* The following functions allow you to get or set info about the selected
- * dline corresponding to the dot or square at [i,j]. You'll get an assertion
- * failure if you talk about a dline that doesn't exist, ie if you ask about
- * non-touching lines around a square. */
-static int get_dot_dline(const game_state *state, const char *dline_array,
- int i, int j, enum dline_desc desc)
-{
-/* fprintf(stderr, "get_dot_dline %p [%d,%d] %s\n", dline_array, i, j, DL2STR(desc)); */
- return BIT_SET(dline_array[i + (state->w + 1) * j], desc);
-}
-
-static int set_dot_dline(game_state *state, char *dline_array,
- int i, int j, enum dline_desc desc
-#ifdef SHOW_WORKING
- , const char *reason
-#endif
- )
+/* i points to the first edge of the dline pair, reading clockwise around
+ * the dot. */
+static int dline_index_from_dot(grid *g, grid_dot *d, int i)
{
+ grid_edge *e = d->edges[i];
int ret;
- ret = SET_BIT(dline_array[i + (state->w + 1) * j], desc);
-
-#ifdef SHOW_WORKING
- if (ret)
- fprintf(stderr, "set_dot_dline %p [%d,%d] %s (%s)\n", dline_array, i, j, DL2STR(desc), reason);
+#ifdef DEBUG_DLINES
+ grid_edge *e2;
+ int i2 = i+1;
+ if (i2 == d->order) i2 = 0;
+ e2 = d->edges[i2];
+#endif
+ ret = 2 * (e - g->edges) + ((e->dot1 == d) ? 1 : 0);
+#ifdef DEBUG_DLINES
+ printf("dline_index_from_dot: d=%d,i=%d, edges [%d,%d] - %d\n",
+ (int)(d - g->dots), i, (int)(e - g->edges),
+ (int)(e2 - g->edges), ret);
#endif
return ret;
}
-
-static int get_square_dline(game_state *state, char *dline_array,
- int i, int j, enum dline_desc desc)
-{
- CHECK_DLINE_SENSIBLE(desc);
-/* fprintf(stderr, "get_square_dline %p [%d,%d] %s\n", dline_array, i, j, DL2STR(desc)); */
- return BIT_SET(dline_array[(i+dlines[desc].dx) + (state->w + 1) * (j+dlines[desc].dy)],
- desc);
-}
-
-static int set_square_dline(game_state *state, char *dline_array,
- int i, int j, enum dline_desc desc
-#ifdef SHOW_WORKING
- , const char *reason
-#endif
- )
+/* i points to the second edge of the dline pair, reading clockwise around
+ * the face. That is, the edges of the dline, starting at edge{i}, read
+ * anti-clockwise around the face. By layout conventions, the common dot
+ * of the dline will be f->dots[i] */
+static int dline_index_from_face(grid *g, grid_face *f, int i)
{
+ grid_edge *e = f->edges[i];
+ grid_dot *d = f->dots[i];
int ret;
- CHECK_DLINE_SENSIBLE(desc);
- ret = SET_BIT(dline_array[(i+dlines[desc].dx) + (state->w + 1) * (j+dlines[desc].dy)], desc);
-#ifdef SHOW_WORKING
- if (ret)
- fprintf(stderr, "set_square_dline %p [%d,%d] %s (%s)\n", dline_array, i, j, DL2STR(desc), reason);
+#ifdef DEBUG_DLINES
+ grid_edge *e2;
+ int i2 = i - 1;
+ if (i2 < 0) i2 += f->order;
+ e2 = f->edges[i2];
+#endif
+ ret = 2 * (e - g->edges) + ((e->dot1 == d) ? 1 : 0);
+#ifdef DEBUG_DLINES
+ printf("dline_index_from_face: f=%d,i=%d, edges [%d,%d] - %d\n",
+ (int)(f - g->faces), i, (int)(e - g->edges),
+ (int)(e2 - g->edges), ret);
#endif
return ret;
}
-
-#ifdef SHOW_WORKING
-#define set_dot_dline(a, b, c, d, e) \
- set_dot_dline(a, b, c, d, e, __FUNCTION__)
-#define set_square_dline(a, b, c, d, e) \
- set_square_dline(a, b, c, d, e, __FUNCTION__)
-#endif
-
-static int set_dot_opp_dline(game_state *state, char *dline_array,
- int i, int j, enum dline_desc desc)
+static int is_atleastone(const char *dline_array, int index)
{
- return set_dot_dline(state, dline_array, i, j, OPP_DLINE(desc));
+ return BIT_SET(dline_array[index], 0);
}
-
-static int set_square_opp_dline(game_state *state, char *dline_array,
- int i, int j, enum dline_desc desc)
+static int set_atleastone(char *dline_array, int index)
{
- return set_square_dline(state, dline_array, i, j, OPP_DLINE(desc));
+ return SET_BIT(dline_array[index], 0);
}
-
-/* Find out if both the lines in the given dline are UNKNOWN */
-static int dline_both_unknown(const game_state *state, int i, int j,
- enum dline_desc desc)
+static int is_atmostone(const char *dline_array, int index)
{
- return
- (get_line_status_from_point(state, i, j, dlines[desc].dir1) == LINE_UNKNOWN) &&
- (get_line_status_from_point(state, i, j, dlines[desc].dir2) == LINE_UNKNOWN);
+ return BIT_SET(dline_array[index], 1);
+}
+static int set_atmostone(char *dline_array, int index)
+{
+ return SET_BIT(dline_array[index], 1);
}
-
-#define SQUARE_DLINES \
- HANDLE_DLINE(DLINE_UL, RIGHTOF_SQUARE, BELOW_SQUARE, 1, 1); \
- HANDLE_DLINE(DLINE_UR, LEFTOF_SQUARE, BELOW_SQUARE, 0, 1); \
- HANDLE_DLINE(DLINE_DL, RIGHTOF_SQUARE, ABOVE_SQUARE, 1, 0); \
- HANDLE_DLINE(DLINE_DR, LEFTOF_SQUARE, ABOVE_SQUARE, 0, 0);
-
-#define DOT_DLINES \
- HANDLE_DLINE(DLINE_UD, ABOVE_DOT, BELOW_DOT); \
- HANDLE_DLINE(DLINE_LR, LEFTOF_DOT, RIGHTOF_DOT); \
- HANDLE_DLINE(DLINE_UL, ABOVE_DOT, LEFTOF_DOT); \
- HANDLE_DLINE(DLINE_UR, ABOVE_DOT, RIGHTOF_DOT); \
- HANDLE_DLINE(DLINE_DL, BELOW_DOT, LEFTOF_DOT); \
- HANDLE_DLINE(DLINE_DR, BELOW_DOT, RIGHTOF_DOT);
static void array_setall(char *array, char from, char to, int len)
{
}
}
-
-
-static int get_line_status_from_point(const game_state *state,
- int x, int y, enum direction d)
+/* Helper, called when doing dline dot deductions, in the case where we
+ * have 4 UNKNOWNs, and two of them (adjacent) have *exactly* one YES between
+ * them (because of dline atmostone/atleastone).
+ * On entry, edge points to the first of these two UNKNOWNs. This function
+ * will find the opposite UNKNOWNS (if they are adjacent to one another)
+ * and set their corresponding dline to atleastone. (Setting atmostone
+ * already happens in earlier dline deductions) */
+static int dline_set_opp_atleastone(solver_state *sstate,
+ grid_dot *d, int edge)
{
- switch (d) {
- case LEFT:
- return LEFTOF_DOT(state, x, y);
- case RIGHT:
- return RIGHTOF_DOT(state, x, y);
- case UP:
- return ABOVE_DOT(state, x, y);
- case DOWN:
- return BELOW_DOT(state, x, y);
+ game_state *state = sstate->state;
+ grid *g = state->game_grid;
+ int N = d->order;
+ int opp, opp2;
+ for (opp = 0; opp < N; opp++) {
+ int opp_dline_index;
+ if (opp == edge || opp == edge+1 || opp == edge-1)
+ continue;
+ if (opp == 0 && edge == N-1)
+ continue;
+ if (opp == N-1 && edge == 0)
+ continue;
+ opp2 = opp + 1;
+ if (opp2 == N) opp2 = 0;
+ /* Check if opp, opp2 point to LINE_UNKNOWNs */
+ if (state->lines[d->edges[opp] - g->edges] != LINE_UNKNOWN)
+ continue;
+ if (state->lines[d->edges[opp2] - g->edges] != LINE_UNKNOWN)
+ continue;
+ /* Found opposite UNKNOWNS and they're next to each other */
+ opp_dline_index = dline_index_from_dot(g, d, opp);
+ return set_atleastone(sstate->dlines, opp_dline_index);
}
-
- return 0;
+ return FALSE;
}
-/* First and second args are coord offset from top left of square to one end
- * of line in question, third and fourth args are the direction from the first
- * end of the line to the second. Fifth arg is the direction of the line from
- * the coord offset position.
- * How confusing.
- */
-#define SQUARE_LINES \
- SQUARE_LINE( 0, 0, RIGHT, RIGHTOF_DOT, UP); \
- SQUARE_LINE( 0, +1, RIGHT, RIGHTOF_DOT, DOWN); \
- SQUARE_LINE( 0, 0, DOWN, BELOW_DOT, LEFT); \
- SQUARE_LINE(+1, 0, DOWN, BELOW_DOT, RIGHT);
-/* Set pairs of lines around this square which are known to be identical to
+/* Set pairs of lines around this face which are known to be identical, to
* the given line_state */
-static int square_setall_identical(solver_state *sstate, int x, int y,
- enum line_state line_new)
+static int face_setall_identical(solver_state *sstate, int face_index,
+ enum line_state line_new)
{
/* can[dir] contains the canonical line associated with the line in
* direction dir from the square in question. Similarly inv[dir] is
* whether or not the line in question is inverse to its canonical
* element. */
- int can[4], inv[4], i, j;
int retval = FALSE;
+ game_state *state = sstate->state;
+ grid *g = state->game_grid;
+ grid_face *f = g->faces + face_index;
+ int N = f->order;
+ int i, j;
+ int can1, can2, inv1, inv2;
- i = 0;
-
-#if 0
- fprintf(stderr, "Setting all identical unknown lines around square "
- "[%d,%d] to %d:\n", x, y, line_new);
-#endif
-
-#define SQUARE_LINE(dx, dy, linedir, dir_dot, sqdir) \
- can[sqdir] = \
- edsf_canonify(sstate->hard->linedsf, \
- LINEDSF_INDEX(sstate->state, x+(dx), y+(dy), linedir), \
- &inv[sqdir]);
-
- SQUARE_LINES;
-
-#undef SQUARE_LINE
-
- for (j = 0; j < 4; ++j) {
- for (i = 0; i < 4; ++i) {
- if (i == j)
+ for (i = 0; i < N; i++) {
+ int line1_index = f->edges[i] - g->edges;
+ if (state->lines[line1_index] != LINE_UNKNOWN)
+ continue;
+ for (j = i + 1; j < N; j++) {
+ int line2_index = f->edges[j] - g->edges;
+ if (state->lines[line2_index] != LINE_UNKNOWN)
continue;
- if (can[i] == can[j] && inv[i] == inv[j]) {
-
- /* Lines in directions i and j are identical.
- * Only do j now, we'll do i when the loop causes us to
- * consider {i,j} in the opposite order. */
-#define SQUARE_LINE(dx, dy, dir, c, sqdir) \
- if (j == sqdir) { \
- retval = set_line_bydot(sstate, x+(dx), y+(dy), dir, line_new); \
- if (retval) { \
- break; \
- } \
- }
-
- SQUARE_LINES;
-
-#undef SQUARE_LINE
+ /* Found two UNKNOWNS */
+ can1 = edsf_canonify(sstate->linedsf, line1_index, &inv1);
+ can2 = edsf_canonify(sstate->linedsf, line2_index, &inv2);
+ if (can1 == can2 && inv1 == inv2) {
+ solver_set_line(sstate, line1_index, line_new);
+ solver_set_line(sstate, line2_index, line_new);
}
}
}
-
return retval;
}
-#if 0
-/* Set all identical lines passing through the current dot to the chosen line
- * state. (implicitly this only looks at UNKNOWN lines) */
-static int dot_setall_identical(solver_state *sstate, int x, int y,
- enum line_state line_new)
-{
- /* The implementation of this is a little naughty but I can't see how to do
- * it elegantly any other way */
- int can[4], inv[4], i, j;
- enum direction d;
- int retval = FALSE;
-
- for (d = 0; d < 4; ++d) {
- can[d] = edsf_canonify(sstate->hard->linedsf,
- LINEDSF_INDEX(sstate->state, x, y, d),
- inv+d);
- }
-
- for (j = 0; j < 4; ++j) {
-next_j:
- for (i = 0; i < j; ++i) {
- if (can[i] == can[j] && inv[i] == inv[j]) {
- /* Lines in directions i and j are identical */
- if (get_line_status_from_point(sstate->state, x, y, j) ==
- LINE_UNKNOWN) {
- set_line_bydot(sstate->state, x, y, j,
- line_new);
- retval = TRUE;
- goto next_j;
- }
- }
-
+/* Given a dot or face, and a count of LINE_UNKNOWNs, find them and
+ * return the edge indices into e. */
+static void find_unknowns(game_state *state,
+ grid_edge **edge_list, /* Edge list to search (from a face or a dot) */
+ int expected_count, /* Number of UNKNOWNs (comes from solver's cache) */
+ int *e /* Returned edge indices */)
+{
+ int c = 0;
+ grid *g = state->game_grid;
+ while (c < expected_count) {
+ int line_index = *edge_list - g->edges;
+ if (state->lines[line_index] == LINE_UNKNOWN) {
+ e[c] = line_index;
+ c++;
}
+ ++edge_list;
}
-
- return retval;
-}
-#endif
-
-static int square_setboth_in_dline(solver_state *sstate, enum dline_desc dd,
- int i, int j, enum line_state line_new)
-{
- int retval = FALSE;
- const struct dline dll = dlines[dd], *dl = &dll;
-
-#if 0
- fprintf(stderr, "square_setboth_in_dline %s [%d,%d] to %d\n",
- DL2STR(dd), i, j, line_new);
-#endif
-
- CHECK_DLINE_SENSIBLE(dd);
-
- retval |=
- set_line_bydot(sstate, i+dl->dx, j+dl->dy, dl->dir1, line_new);
- retval |=
- set_line_bydot(sstate, i+dl->dx, j+dl->dy, dl->dir2, line_new);
-
- return retval;
-}
-
-/* Call this function to register that the two unknown lines going into the dot
- * [x,y] are identical or opposite (depending on the value of 'inverse'). This
- * function will cause an assertion failure if anything other than exactly two
- * lines into the dot are unknown.
- * As usual returns TRUE if any progress was made, otherwise FALSE. */
-static int dot_relate_2_unknowns(solver_state *sstate, int x, int y, int inverse)
-{
- enum direction d1=DOWN, d2=DOWN; /* Just to keep compiler quiet */
- int dirs_set = 0;
-
-#define TRY_DIR(d) \
- if (get_line_status_from_point(sstate->state, x, y, d) == \
- LINE_UNKNOWN) { \
- if (dirs_set == 0) \
- d1 = d; \
- else { \
- assert(dirs_set == 1); \
- d2 = d; \
- } \
- dirs_set++; \
- } while (0)
-
- TRY_DIR(UP);
- TRY_DIR(DOWN);
- TRY_DIR(LEFT);
- TRY_DIR(RIGHT);
-#undef TRY_DIR
-
- assert(dirs_set == 2);
- assert(d1 != d2);
-
-#if 0
- fprintf(stderr, "Lines in direction %s and %s from dot [%d,%d] are %s\n",
- DIR2STR(d1), DIR2STR(d2), x, y, inverse?"opposite":"the same");
-#endif
-
- return merge_lines(sstate, x, y, d1, x, y, d2, inverse);
-}
-
-/* Very similar to dot_relate_2_unknowns. */
-static int square_relate_2_unknowns(solver_state *sstate, int x, int y, int inverse)
-{
- enum direction d1=DOWN, d2=DOWN;
- int x1=-1, y1=-1, x2=-1, y2=-1;
- int dirs_set = 0;
-
-#if 0
- fprintf(stderr, "2 unknowns around square [%d,%d] are %s\n",
- x, y, inverse?"opposite":"the same");
-#endif
-
-#define TRY_DIR(i, j, d, dir_sq) \
- do { \
- if (dir_sq(sstate->state, x, y) == LINE_UNKNOWN) { \
- if (dirs_set == 0) { \
- d1 = d; x1 = i; y1 = j; \
- } else { \
- assert(dirs_set == 1); \
- d2 = d; x2 = i; y2 = j; \
- } \
- dirs_set++; \
- } \
- } while (0)
-
- TRY_DIR(x, y, RIGHT, ABOVE_SQUARE);
- TRY_DIR(x, y, DOWN, LEFTOF_SQUARE);
- TRY_DIR(x+1, y, DOWN, RIGHTOF_SQUARE);
- TRY_DIR(x, y+1, RIGHT, BELOW_SQUARE);
-#undef TRY_DIR
-
- assert(dirs_set == 2);
-
-#if 0
- fprintf(stderr, "Line in direction %s from dot [%d,%d] and line in direction %s from dot [%2d,%2d] are %s\n",
- DIR2STR(d1), x1, y1, DIR2STR(d2), x2, y2, inverse?"opposite":"the same");
-#endif
-
- return merge_lines(sstate, x1, y1, d1, x2, y2, d2, inverse);
}
-/* Figure out if any dlines can be 'collapsed' (and do so if they can). This
- * can happen if one of the lines is known and due to the dline status this
- * tells us state of the other, or if there's an interaction with the linedsf
- * (ie if atmostone is set for a dline and the lines are known identical they
- * must both be LINE_NO, etc). XXX at the moment only the former is
- * implemented, and indeed the latter should be implemented in the hard mode
- * solver only.
- */
-static int dot_collapse_dlines(solver_state *sstate, int i, int j)
+/* If we have a list of edges, and we know whether the number of YESs should
+ * be odd or even, and there are only a few UNKNOWNs, we can do some simple
+ * linedsf deductions. This can be used for both face and dot deductions.
+ * Returns the difficulty level of the next solver that should be used,
+ * or DIFF_MAX if no progress was made. */
+static int parity_deductions(solver_state *sstate,
+ grid_edge **edge_list, /* Edge list (from a face or a dot) */
+ int total_parity, /* Expected number of YESs modulo 2 (either 0 or 1) */
+ int unknown_count)
{
- int progress = FALSE;
- enum direction dir1, dir2;
- int dir1st;
- int dlset;
game_state *state = sstate->state;
- enum dline_desc dd;
-
- for (dir1 = 0; dir1 < 4; dir1++) {
- dir1st = get_line_status_from_point(state, i, j, dir1);
- if (dir1st == LINE_UNKNOWN)
- continue;
- /* dir2 iterates over the whole range rather than starting at dir1+1
- * because test below is asymmetric */
- for (dir2 = 0; dir2 < 4; dir2++) {
- if (dir1 == dir2)
- continue;
-
- if ((i == 0 && (dir1 == LEFT || dir2 == LEFT)) ||
- (j == 0 && (dir1 == UP || dir2 == UP)) ||
- (i == state->w && (dir1 == RIGHT || dir2 == RIGHT)) ||
- (j == state->h && (dir1 == DOWN || dir2 == DOWN))) {
- continue;
- }
-
-#if 0
- fprintf(stderr, "dot_collapse_dlines [%d,%d], %s %s\n", i, j,
- DIR2STR(dir1), DIR2STR(dir2));
-#endif
-
- if (get_line_status_from_point(state, i, j, dir2) ==
- LINE_UNKNOWN) {
- dd = dline_desc_from_dirs(dir1, dir2);
-
- dlset = get_dot_dline(state, sstate->normal->dot_atmostone, i, j, dd);
- if (dlset && dir1st == LINE_YES) {
-/* fprintf(stderr, "setting %s to NO\n", DIR2STR(dir2)); */
- progress |=
- set_line_bydot(sstate, i, j, dir2, LINE_NO);
- }
-
- dlset = get_dot_dline(state, sstate->normal->dot_atleastone, i, j, dd);
- if (dlset && dir1st == LINE_NO) {
-/* fprintf(stderr, "setting %s to YES\n", DIR2STR(dir2)); */
- progress |=
- set_line_bydot(sstate, i, j, dir2, LINE_YES);
- }
- }
+ int diff = DIFF_MAX;
+ int *linedsf = sstate->linedsf;
+
+ if (unknown_count == 2) {
+ /* Lines are known alike/opposite, depending on inv. */
+ int e[2];
+ find_unknowns(state, edge_list, 2, e);
+ if (merge_lines(sstate, e[0], e[1], total_parity))
+ diff = min(diff, DIFF_HARD);
+ } else if (unknown_count == 3) {
+ int e[3];
+ int can[3]; /* canonical edges */
+ int inv[3]; /* whether can[x] is inverse to e[x] */
+ find_unknowns(state, edge_list, 3, e);
+ can[0] = edsf_canonify(linedsf, e[0], inv);
+ can[1] = edsf_canonify(linedsf, e[1], inv+1);
+ can[2] = edsf_canonify(linedsf, e[2], inv+2);
+ if (can[0] == can[1]) {
+ if (solver_set_line(sstate, e[2], (total_parity^inv[0]^inv[1]) ?
+ LINE_YES : LINE_NO))
+ diff = min(diff, DIFF_EASY);
+ }
+ if (can[0] == can[2]) {
+ if (solver_set_line(sstate, e[1], (total_parity^inv[0]^inv[2]) ?
+ LINE_YES : LINE_NO))
+ diff = min(diff, DIFF_EASY);
+ }
+ if (can[1] == can[2]) {
+ if (solver_set_line(sstate, e[0], (total_parity^inv[1]^inv[2]) ?
+ LINE_YES : LINE_NO))
+ diff = min(diff, DIFF_EASY);
+ }
+ } else if (unknown_count == 4) {
+ int e[4];
+ int can[4]; /* canonical edges */
+ int inv[4]; /* whether can[x] is inverse to e[x] */
+ find_unknowns(state, edge_list, 4, e);
+ can[0] = edsf_canonify(linedsf, e[0], inv);
+ can[1] = edsf_canonify(linedsf, e[1], inv+1);
+ can[2] = edsf_canonify(linedsf, e[2], inv+2);
+ can[3] = edsf_canonify(linedsf, e[3], inv+3);
+ if (can[0] == can[1]) {
+ if (merge_lines(sstate, e[2], e[3], total_parity^inv[0]^inv[1]))
+ diff = min(diff, DIFF_HARD);
+ } else if (can[0] == can[2]) {
+ if (merge_lines(sstate, e[1], e[3], total_parity^inv[0]^inv[2]))
+ diff = min(diff, DIFF_HARD);
+ } else if (can[0] == can[3]) {
+ if (merge_lines(sstate, e[1], e[2], total_parity^inv[0]^inv[3]))
+ diff = min(diff, DIFF_HARD);
+ } else if (can[1] == can[2]) {
+ if (merge_lines(sstate, e[0], e[3], total_parity^inv[1]^inv[2]))
+ diff = min(diff, DIFF_HARD);
+ } else if (can[1] == can[3]) {
+ if (merge_lines(sstate, e[0], e[2], total_parity^inv[1]^inv[3]))
+ diff = min(diff, DIFF_HARD);
+ } else if (can[2] == can[3]) {
+ if (merge_lines(sstate, e[0], e[1], total_parity^inv[2]^inv[3]))
+ diff = min(diff, DIFF_HARD);
}
}
-
- return progress;
+ return diff;
}
+
/*
- * These are the main solver functions.
+ * These are the main solver functions.
*
* Their return values are diff values corresponding to the lowest mode solver
* that would notice the work that they have done. For example if the normal
* mode solver adds actual lines or crosses, it will return DIFF_EASY as the
* easy mode solver might be able to make progress using that. It doesn't make
* sense for one of them to return a diff value higher than that of the
- * function itself.
+ * function itself.
*
* Each function returns the lowest value it can, as early as possible, in
* order to try and pass as much work as possible back to the lower level
* (easiest first) until either a deduction is made (and an event therefore
* emerges) or no further deductions can be made (in which case we've failed).
*
- * QUESTIONS:
+ * QUESTIONS:
* * How do we 'loop over' a solver when both dots and squares are concerned.
* Answer: first all squares then all dots.
*/
-static int easy_mode_deductions(solver_state *sstate)
+static int trivial_deductions(solver_state *sstate)
{
- int i, j, h, w, current_yes, current_no;
- game_state *state;
+ int i, current_yes, current_no;
+ game_state *state = sstate->state;
+ grid *g = state->game_grid;
int diff = DIFF_MAX;
- state = sstate->state;
- h = state->h;
- w = state->w;
-
- /* Per-square deductions */
- FORALL_SQUARES(state, i, j) {
- if (sstate->square_solved[SQUARE_INDEX(state, i, j)])
+ /* Per-face deductions */
+ for (i = 0; i < g->num_faces; i++) {
+ grid_face *f = g->faces + i;
+
+ if (sstate->face_solved[i])
continue;
- current_yes = SQUARE_YES_COUNT(sstate, i, j);
- current_no = SQUARE_NO_COUNT(sstate, i, j);
+ current_yes = sstate->face_yes_count[i];
+ current_no = sstate->face_no_count[i];
- if (current_yes + current_no == 4) {
- sstate->square_solved[SQUARE_INDEX(state, i, j)] = TRUE;
-/* diff = min(diff, DIFF_EASY); */
+ if (current_yes + current_no == f->order) {
+ sstate->face_solved[i] = TRUE;
continue;
}
- if (CLUE_AT(state, i, j) < 0)
+ if (state->clues[i] < 0)
continue;
- if (CLUE_AT(state, i, j) < current_yes) {
-#if 0
- fprintf(stderr, "detected error [%d,%d] in %s at line %d\n", i, j, __FUNCTION__, __LINE__);
-#endif
+ /*
+ * This code checks whether the numeric clue on a face is so
+ * large as to permit all its remaining LINE_UNKNOWNs to be
+ * filled in as LINE_YES, or alternatively so small as to
+ * permit them all to be filled in as LINE_NO.
+ */
+
+ if (state->clues[i] < current_yes) {
sstate->solver_status = SOLVER_MISTAKE;
return DIFF_EASY;
}
- if (CLUE_AT(state, i, j) == current_yes) {
- if (square_setall(sstate, i, j, LINE_UNKNOWN, LINE_NO))
+ if (state->clues[i] == current_yes) {
+ if (face_setall(sstate, i, LINE_UNKNOWN, LINE_NO))
diff = min(diff, DIFF_EASY);
- sstate->square_solved[SQUARE_INDEX(state, i, j)] = TRUE;
+ sstate->face_solved[i] = TRUE;
continue;
}
- if (4 - CLUE_AT(state, i, j) < current_no) {
-#if 0
- fprintf(stderr, "detected error [%d,%d] in %s at line %d\n", i, j, __FUNCTION__, __LINE__);
-#endif
+ if (f->order - state->clues[i] < current_no) {
sstate->solver_status = SOLVER_MISTAKE;
return DIFF_EASY;
}
- if (4 - CLUE_AT(state, i, j) == current_no) {
- if (square_setall(sstate, i, j, LINE_UNKNOWN, LINE_YES))
+ if (f->order - state->clues[i] == current_no) {
+ if (face_setall(sstate, i, LINE_UNKNOWN, LINE_YES))
diff = min(diff, DIFF_EASY);
- sstate->square_solved[SQUARE_INDEX(state, i, j)] = TRUE;
+ sstate->face_solved[i] = TRUE;
continue;
}
+
+ if (f->order - state->clues[i] == current_no + 1 &&
+ f->order - current_yes - current_no > 2) {
+ /*
+ * One small refinement to the above: we also look for any
+ * adjacent pair of LINE_UNKNOWNs around the face with
+ * some LINE_YES incident on it from elsewhere. If we find
+ * one, then we know that pair of LINE_UNKNOWNs can't
+ * _both_ be LINE_YES, and hence that pushes us one line
+ * closer to being able to determine all the rest.
+ */
+ int j, k, e1, e2, e, d;
+
+ for (j = 0; j < f->order; j++) {
+ e1 = f->edges[j] - g->edges;
+ e2 = f->edges[j+1 < f->order ? j+1 : 0] - g->edges;
+
+ if (g->edges[e1].dot1 == g->edges[e2].dot1 ||
+ g->edges[e1].dot1 == g->edges[e2].dot2) {
+ d = g->edges[e1].dot1 - g->dots;
+ } else {
+ assert(g->edges[e1].dot2 == g->edges[e2].dot1 ||
+ g->edges[e1].dot2 == g->edges[e2].dot2);
+ d = g->edges[e1].dot2 - g->dots;
+ }
+
+ if (state->lines[e1] == LINE_UNKNOWN &&
+ state->lines[e2] == LINE_UNKNOWN) {
+ for (k = 0; k < g->dots[d].order; k++) {
+ int e = g->dots[d].edges[k] - g->edges;
+ if (state->lines[e] == LINE_YES)
+ goto found; /* multi-level break */
+ }
+ }
+ }
+ continue;
+
+ found:
+ /*
+ * If we get here, we've found such a pair of edges, and
+ * they're e1 and e2.
+ */
+ for (j = 0; j < f->order; j++) {
+ e = f->edges[j] - g->edges;
+ if (state->lines[e] == LINE_UNKNOWN && e != e1 && e != e2) {
+ int r = solver_set_line(sstate, e, LINE_YES);
+ assert(r);
+ diff = min(diff, DIFF_EASY);
+ }
+ }
+ }
}
check_caches(sstate);
/* Per-dot deductions */
- FORALL_DOTS(state, i, j) {
- if (sstate->dot_solved[DOT_INDEX(state, i, j)])
+ for (i = 0; i < g->num_dots; i++) {
+ grid_dot *d = g->dots + i;
+ int yes, no, unknown;
+
+ if (sstate->dot_solved[i])
continue;
- switch (DOT_YES_COUNT(sstate, i, j)) {
- case 0:
- switch (DOT_NO_COUNT(sstate, i, j)) {
- case 3:
-#if 0
- fprintf(stderr, "dot [%d,%d]: 0 yes, 3 no\n", i, j);
-#endif
- dot_setall(sstate, i, j, LINE_UNKNOWN, LINE_NO);
- diff = min(diff, DIFF_EASY);
- /* fall through */
- case 4:
- sstate->dot_solved[DOT_INDEX(state, i, j)] = TRUE;
- break;
- }
- break;
- case 1:
- switch (DOT_NO_COUNT(sstate, i, j)) {
- case 2: /* 1 yes, 2 no */
-#if 0
- fprintf(stderr, "dot [%d,%d]: 1 yes, 2 no\n", i, j);
-#endif
- dot_setall(sstate, i, j, LINE_UNKNOWN, LINE_YES);
- diff = min(diff, DIFF_EASY);
- sstate->dot_solved[DOT_INDEX(state, i, j)] = TRUE;
- break;
- case 3: /* 1 yes, 3 no */
-#if 0
- fprintf(stderr, "detected error [%d,%d] in %s at line %d\n", i, j, __FUNCTION__, __LINE__);
-#endif
- sstate->solver_status = SOLVER_MISTAKE;
- return DIFF_EASY;
- }
- break;
- case 2:
-#if 0
- fprintf(stderr, "dot [%d,%d]: 2 yes\n", i, j);
-#endif
- dot_setall(sstate, i, j, LINE_UNKNOWN, LINE_NO);
+ yes = sstate->dot_yes_count[i];
+ no = sstate->dot_no_count[i];
+ unknown = d->order - yes - no;
+
+ if (yes == 0) {
+ if (unknown == 0) {
+ sstate->dot_solved[i] = TRUE;
+ } else if (unknown == 1) {
+ dot_setall(sstate, i, LINE_UNKNOWN, LINE_NO);
diff = min(diff, DIFF_EASY);
- sstate->dot_solved[DOT_INDEX(state, i, j)] = TRUE;
- break;
- case 3:
- case 4:
-#if 0
- fprintf(stderr, "detected error [%d,%d] in %s at line %d\n", i, j, __FUNCTION__, __LINE__);
-#endif
+ sstate->dot_solved[i] = TRUE;
+ }
+ } else if (yes == 1) {
+ if (unknown == 0) {
sstate->solver_status = SOLVER_MISTAKE;
return DIFF_EASY;
+ } else if (unknown == 1) {
+ dot_setall(sstate, i, LINE_UNKNOWN, LINE_YES);
+ diff = min(diff, DIFF_EASY);
+ }
+ } else if (yes == 2) {
+ if (unknown > 0) {
+ dot_setall(sstate, i, LINE_UNKNOWN, LINE_NO);
+ diff = min(diff, DIFF_EASY);
+ }
+ sstate->dot_solved[i] = TRUE;
+ } else {
+ sstate->solver_status = SOLVER_MISTAKE;
+ return DIFF_EASY;
}
}
return diff;
}
-static int normal_mode_deductions(solver_state *sstate)
+static int dline_deductions(solver_state *sstate)
{
- int i, j;
game_state *state = sstate->state;
- enum dline_desc dd;
+ grid *g = state->game_grid;
+ char *dlines = sstate->dlines;
+ int i;
int diff = DIFF_MAX;
- FORALL_SQUARES(state, i, j) {
- if (sstate->square_solved[SQUARE_INDEX(state, i, j)])
- continue;
+ /* ------ Face deductions ------ */
+
+ /* Given a set of dline atmostone/atleastone constraints, need to figure
+ * out if we can deduce any further info. For more general faces than
+ * squares, this turns out to be a tricky problem.
+ * The approach taken here is to define (per face) NxN matrices:
+ * "maxs" and "mins".
+ * The entries maxs(j,k) and mins(j,k) define the upper and lower limits
+ * for the possible number of edges that are YES between positions j and k
+ * going clockwise around the face. Can think of j and k as marking dots
+ * around the face (recall the labelling scheme: edge0 joins dot0 to dot1,
+ * edge1 joins dot1 to dot2 etc).
+ * Trivially, mins(j,j) = maxs(j,j) = 0, and we don't even bother storing
+ * these. mins(j,j+1) and maxs(j,j+1) are determined by whether edge{j}
+ * is YES, NO or UNKNOWN. mins(j,j+2) and maxs(j,j+2) are related to
+ * the dline atmostone/atleastone status for edges j and j+1.
+ *
+ * Then we calculate the remaining entries recursively. We definitely
+ * know that
+ * mins(j,k) >= { mins(j,u) + mins(u,k) } for any u between j and k.
+ * This is because any valid placement of YESs between j and k must give
+ * a valid placement between j and u, and also between u and k.
+ * I believe it's sufficient to use just the two values of u:
+ * j+1 and j+2. Seems to work well in practice - the bounds we compute
+ * are rigorous, even if they might not be best-possible.
+ *
+ * Once we have maxs and mins calculated, we can make inferences about
+ * each dline{j,j+1} by looking at the possible complementary edge-counts
+ * mins(j+2,j) and maxs(j+2,j) and comparing these with the face clue.
+ * As well as dlines, we can make similar inferences about single edges.
+ * For example, consider a pentagon with clue 3, and we know at most one
+ * of (edge0, edge1) is YES, and at most one of (edge2, edge3) is YES.
+ * We could then deduce edge4 is YES, because maxs(0,4) would be 2, so
+ * that final edge would have to be YES to make the count up to 3.
+ */
- if (CLUE_AT(state, i, j) < 0)
+ /* Much quicker to allocate arrays on the stack than the heap, so
+ * define the largest possible face size, and base our array allocations
+ * on that. We check this with an assertion, in case someone decides to
+ * make a grid which has larger faces than this. Note, this algorithm
+ * could get quite expensive if there are many large faces. */
+#define MAX_FACE_SIZE 12
+
+ for (i = 0; i < g->num_faces; i++) {
+ int maxs[MAX_FACE_SIZE][MAX_FACE_SIZE];
+ int mins[MAX_FACE_SIZE][MAX_FACE_SIZE];
+ grid_face *f = g->faces + i;
+ int N = f->order;
+ int j,m;
+ int clue = state->clues[i];
+ assert(N <= MAX_FACE_SIZE);
+ if (sstate->face_solved[i])
continue;
+ if (clue < 0) continue;
+
+ /* Calculate the (j,j+1) entries */
+ for (j = 0; j < N; j++) {
+ int edge_index = f->edges[j] - g->edges;
+ int dline_index;
+ enum line_state line1 = state->lines[edge_index];
+ enum line_state line2;
+ int tmp;
+ int k = j + 1;
+ if (k >= N) k = 0;
+ maxs[j][k] = (line1 == LINE_NO) ? 0 : 1;
+ mins[j][k] = (line1 == LINE_YES) ? 1 : 0;
+ /* Calculate the (j,j+2) entries */
+ dline_index = dline_index_from_face(g, f, k);
+ edge_index = f->edges[k] - g->edges;
+ line2 = state->lines[edge_index];
+ k++;
+ if (k >= N) k = 0;
+
+ /* max */
+ tmp = 2;
+ if (line1 == LINE_NO) tmp--;
+ if (line2 == LINE_NO) tmp--;
+ if (tmp == 2 && is_atmostone(dlines, dline_index))
+ tmp = 1;
+ maxs[j][k] = tmp;
+
+ /* min */
+ tmp = 0;
+ if (line1 == LINE_YES) tmp++;
+ if (line2 == LINE_YES) tmp++;
+ if (tmp == 0 && is_atleastone(dlines, dline_index))
+ tmp = 1;
+ mins[j][k] = tmp;
+ }
- switch (CLUE_AT(state, i, j)) {
- case 1:
-#if 0
- fprintf(stderr, "clue [%d,%d] is 1, doing dline ops\n",
- i, j);
-#endif
- FORALL_SQUARE_DLINES(dd) {
- /* At most one of any DLINE can be set */
- if (set_square_dline(state,
- sstate->normal->dot_atmostone,
- i, j, dd)) {
- diff = min(diff, DIFF_NORMAL);
- }
+ /* Calculate the (j,j+m) entries for m between 3 and N-1 */
+ for (m = 3; m < N; m++) {
+ for (j = 0; j < N; j++) {
+ int k = j + m;
+ int u = j + 1;
+ int v = j + 2;
+ int tmp;
+ if (k >= N) k -= N;
+ if (u >= N) u -= N;
+ if (v >= N) v -= N;
+ maxs[j][k] = maxs[j][u] + maxs[u][k];
+ mins[j][k] = mins[j][u] + mins[u][k];
+ tmp = maxs[j][v] + maxs[v][k];
+ maxs[j][k] = min(maxs[j][k], tmp);
+ tmp = mins[j][v] + mins[v][k];
+ mins[j][k] = max(mins[j][k], tmp);
+ }
+ }
- if (get_square_dline(state,
- sstate->normal->dot_atleastone,
- i, j, dd)) {
- /* This DLINE provides enough YESes to solve the clue */
- if (square_setboth_in_dline(sstate, OPP_DLINE(dd),
- i, j, LINE_NO)) {
- diff = min(diff, DIFF_EASY);
- }
- }
- }
+ /* See if we can make any deductions */
+ for (j = 0; j < N; j++) {
+ int k;
+ grid_edge *e = f->edges[j];
+ int line_index = e - g->edges;
+ int dline_index;
- break;
- case 2:
- /* If at least one of one DLINE is set, at most one
- * of the opposing one is and vice versa */
-#if 0
- fprintf(stderr, "clue [%d,%d] is 2, doing dline ops\n",
- i, j);
-#endif
- FORALL_SQUARE_DLINES(dd) {
- if (get_square_dline(state,
- sstate->normal->dot_atmostone,
- i, j, dd)) {
- if (set_square_opp_dline(state,
- sstate->normal->dot_atleastone,
- i, j, dd)) {
- diff = min(diff, DIFF_NORMAL);
- }
- }
- if (get_square_dline(state,
- sstate->normal->dot_atleastone,
- i, j, dd)) {
- if (set_square_opp_dline(state,
- sstate->normal->dot_atmostone,
- i, j, dd)) {
- diff = min(diff, DIFF_NORMAL);
- }
- }
+ if (state->lines[line_index] != LINE_UNKNOWN)
+ continue;
+ k = j + 1;
+ if (k >= N) k = 0;
+
+ /* minimum YESs in the complement of this edge */
+ if (mins[k][j] > clue) {
+ sstate->solver_status = SOLVER_MISTAKE;
+ return DIFF_EASY;
+ }
+ if (mins[k][j] == clue) {
+ /* setting this edge to YES would make at least
+ * (clue+1) edges - contradiction */
+ solver_set_line(sstate, line_index, LINE_NO);
+ diff = min(diff, DIFF_EASY);
+ }
+ if (maxs[k][j] < clue - 1) {
+ sstate->solver_status = SOLVER_MISTAKE;
+ return DIFF_EASY;
+ }
+ if (maxs[k][j] == clue - 1) {
+ /* Only way to satisfy the clue is to set edge{j} as YES */
+ solver_set_line(sstate, line_index, LINE_YES);
+ diff = min(diff, DIFF_EASY);
+ }
+
+ /* More advanced deduction that allows propagation along diagonal
+ * chains of faces connected by dots, for example, 3-2-...-2-3
+ * in square grids. */
+ if (sstate->diff >= DIFF_TRICKY) {
+ /* Now see if we can make dline deduction for edges{j,j+1} */
+ e = f->edges[k];
+ if (state->lines[e - g->edges] != LINE_UNKNOWN)
+ /* Only worth doing this for an UNKNOWN,UNKNOWN pair.
+ * Dlines where one of the edges is known, are handled in the
+ * dot-deductions */
+ continue;
+
+ dline_index = dline_index_from_face(g, f, k);
+ k++;
+ if (k >= N) k = 0;
+
+ /* minimum YESs in the complement of this dline */
+ if (mins[k][j] > clue - 2) {
+ /* Adding 2 YESs would break the clue */
+ if (set_atmostone(dlines, dline_index))
+ diff = min(diff, DIFF_NORMAL);
}
- break;
- case 3:
-#if 0
- fprintf(stderr, "clue [%d,%d] is 3, doing dline ops\n",
- i, j);
-#endif
- FORALL_SQUARE_DLINES(dd) {
- /* At least one of any DLINE must be set */
- if (set_square_dline(state,
- sstate->normal->dot_atleastone,
- i, j, dd)) {
+ /* maximum YESs in the complement of this dline */
+ if (maxs[k][j] < clue) {
+ /* Adding 2 NOs would mean not enough YESs */
+ if (set_atleastone(dlines, dline_index))
diff = min(diff, DIFF_NORMAL);
- }
-
- if (get_square_dline(state,
- sstate->normal->dot_atmostone,
- i, j, dd)) {
- /* This DLINE provides enough NOs to solve the clue */
- if (square_setboth_in_dline(sstate, OPP_DLINE(dd),
- i, j, LINE_YES)) {
- diff = min(diff, DIFF_EASY);
- }
- }
}
- break;
+ }
}
}
- check_caches(sstate);
-
if (diff < DIFF_NORMAL)
return diff;
- FORALL_DOTS(state, i, j) {
- if (sstate->dot_solved[DOT_INDEX(state, i, j)])
- continue;
+ /* ------ Dot deductions ------ */
-#if 0
- text = game_text_format(state);
- fprintf(stderr, "-----------------\n%s", text);
- sfree(text);
-#endif
+ for (i = 0; i < g->num_dots; i++) {
+ grid_dot *d = g->dots + i;
+ int N = d->order;
+ int yes, no, unknown;
+ int j;
+ if (sstate->dot_solved[i])
+ continue;
+ yes = sstate->dot_yes_count[i];
+ no = sstate->dot_no_count[i];
+ unknown = N - yes - no;
+
+ for (j = 0; j < N; j++) {
+ int k;
+ int dline_index;
+ int line1_index, line2_index;
+ enum line_state line1, line2;
+ k = j + 1;
+ if (k >= N) k = 0;
+ dline_index = dline_index_from_dot(g, d, j);
+ line1_index = d->edges[j] - g->edges;
+ line2_index = d->edges[k] - g->edges;
+ line1 = state->lines[line1_index];
+ line2 = state->lines[line2_index];
+
+ /* Infer dline state from line state */
+ if (line1 == LINE_NO || line2 == LINE_NO) {
+ if (set_atmostone(dlines, dline_index))
+ diff = min(diff, DIFF_NORMAL);
+ }
+ if (line1 == LINE_YES || line2 == LINE_YES) {
+ if (set_atleastone(dlines, dline_index))
+ diff = min(diff, DIFF_NORMAL);
+ }
+ /* Infer line state from dline state */
+ if (is_atmostone(dlines, dline_index)) {
+ if (line1 == LINE_YES && line2 == LINE_UNKNOWN) {
+ solver_set_line(sstate, line2_index, LINE_NO);
+ diff = min(diff, DIFF_EASY);
+ }
+ if (line2 == LINE_YES && line1 == LINE_UNKNOWN) {
+ solver_set_line(sstate, line1_index, LINE_NO);
+ diff = min(diff, DIFF_EASY);
+ }
+ }
+ if (is_atleastone(dlines, dline_index)) {
+ if (line1 == LINE_NO && line2 == LINE_UNKNOWN) {
+ solver_set_line(sstate, line2_index, LINE_YES);
+ diff = min(diff, DIFF_EASY);
+ }
+ if (line2 == LINE_NO && line1 == LINE_UNKNOWN) {
+ solver_set_line(sstate, line1_index, LINE_YES);
+ diff = min(diff, DIFF_EASY);
+ }
+ }
+ /* Deductions that depend on the numbers of lines.
+ * Only bother if both lines are UNKNOWN, otherwise the
+ * easy-mode solver (or deductions above) would have taken
+ * care of it. */
+ if (line1 != LINE_UNKNOWN || line2 != LINE_UNKNOWN)
+ continue;
- switch (DOT_YES_COUNT(sstate, i, j)) {
- case 0:
- switch (DOT_NO_COUNT(sstate, i, j)) {
- case 1:
- /* Make note that at most one of each unknown DLINE
- * is YES */
- break;
+ if (yes == 0 && unknown == 2) {
+ /* Both these unknowns must be identical. If we know
+ * atmostone or atleastone, we can make progress. */
+ if (is_atmostone(dlines, dline_index)) {
+ solver_set_line(sstate, line1_index, LINE_NO);
+ solver_set_line(sstate, line2_index, LINE_NO);
+ diff = min(diff, DIFF_EASY);
+ }
+ if (is_atleastone(dlines, dline_index)) {
+ solver_set_line(sstate, line1_index, LINE_YES);
+ solver_set_line(sstate, line2_index, LINE_YES);
+ diff = min(diff, DIFF_EASY);
+ }
+ }
+ if (yes == 1) {
+ if (set_atmostone(dlines, dline_index))
+ diff = min(diff, DIFF_NORMAL);
+ if (unknown == 2) {
+ if (set_atleastone(dlines, dline_index))
+ diff = min(diff, DIFF_NORMAL);
+ }
}
- break;
- case 1:
- switch (DOT_NO_COUNT(sstate, i, j)) {
- case 1:
- /* 1 yes, 1 no, so exactly one of unknowns is
- * yes */
-#if 0
- fprintf(stderr, "dot [%d,%d]: 1 yes, 1 no\n", i, j);
-#endif
- FORALL_DOT_DLINES(dd) {
- if (dline_both_unknown(state,
- i, j, dd)) {
- if (set_dot_dline(state,
- sstate->normal->dot_atleastone,
- i, j, dd)) {
- diff = min(diff, DIFF_NORMAL);
- }
- }
+ /* More advanced deduction that allows propagation along diagonal
+ * chains of faces connected by dots, for example: 3-2-...-2-3
+ * in square grids. */
+ if (sstate->diff >= DIFF_TRICKY) {
+ /* If we have atleastone set for this dline, infer
+ * atmostone for each "opposite" dline (that is, each
+ * dline without edges in common with this one).
+ * Again, this test is only worth doing if both these
+ * lines are UNKNOWN. For if one of these lines were YES,
+ * the (yes == 1) test above would kick in instead. */
+ if (is_atleastone(dlines, dline_index)) {
+ int opp;
+ for (opp = 0; opp < N; opp++) {
+ int opp_dline_index;
+ if (opp == j || opp == j+1 || opp == j-1)
+ continue;
+ if (j == 0 && opp == N-1)
+ continue;
+ if (j == N-1 && opp == 0)
+ continue;
+ opp_dline_index = dline_index_from_dot(g, d, opp);
+ if (set_atmostone(dlines, opp_dline_index))
+ diff = min(diff, DIFF_NORMAL);
}
-
- /* fall through */
- case 0:
-#if 0
- fprintf(stderr, "dot [%d,%d]: 1 yes, 0 or 1 no\n", i, j);
-#endif
- /* 1 yes, fewer than 2 no, so at most one of
- * unknowns is yes */
- FORALL_DOT_DLINES(dd) {
- if (dline_both_unknown(state,
- i, j, dd)) {
- if (set_dot_dline(state,
- sstate->normal->dot_atmostone,
- i, j, dd)) {
- diff = min(diff, DIFF_NORMAL);
+ if (yes == 0 && is_atmostone(dlines, dline_index)) {
+ /* This dline has *exactly* one YES and there are no
+ * other YESs. This allows more deductions. */
+ if (unknown == 3) {
+ /* Third unknown must be YES */
+ for (opp = 0; opp < N; opp++) {
+ int opp_index;
+ if (opp == j || opp == k)
+ continue;
+ opp_index = d->edges[opp] - g->edges;
+ if (state->lines[opp_index] == LINE_UNKNOWN) {
+ solver_set_line(sstate, opp_index,
+ LINE_YES);
+ diff = min(diff, DIFF_EASY);
+ }
}
+ } else if (unknown == 4) {
+ /* Exactly one of opposite UNKNOWNS is YES. We've
+ * already set atmostone, so set atleastone as
+ * well.
+ */
+ if (dline_set_opp_atleastone(sstate, d, j))
+ diff = min(diff, DIFF_NORMAL);
}
}
- break;
- }
- break;
- }
-
- /* DLINE deductions that don't depend on the exact number of
- * LINE_YESs or LINE_NOs */
-
- /* If at least one of a dline in a dot is YES, at most one
- * of the opposite dline to that dot must be YES. */
- FORALL_DOT_DLINES(dd) {
- if (get_dot_dline(state,
- sstate->normal->dot_atleastone,
- i, j, dd)) {
- if (set_dot_opp_dline(state,
- sstate->normal->dot_atmostone,
- i, j, dd)) {
- diff = min(diff, DIFF_NORMAL);
}
}
}
-
- if (dot_collapse_dlines(sstate, i, j))
- diff = min(diff, DIFF_EASY);
}
- check_caches(sstate);
-
return diff;
}
-static int hard_mode_deductions(solver_state *sstate)
+static int linedsf_deductions(solver_state *sstate)
{
- int i, j, a, b, s;
game_state *state = sstate->state;
- const int h=state->h, w=state->w;
- enum direction dir1, dir2;
- int can1, can2, inv1, inv2;
+ grid *g = state->game_grid;
+ char *dlines = sstate->dlines;
+ int i;
int diff = DIFF_MAX;
- enum dline_desc dd;
+ int diff_tmp;
- FORALL_SQUARES(state, i, j) {
- if (sstate->square_solved[SQUARE_INDEX(state, i, j)])
- continue;
+ /* ------ Face deductions ------ */
- switch (CLUE_AT(state, i, j)) {
- case -1:
- continue;
+ /* A fully-general linedsf deduction seems overly complicated
+ * (I suspect the problem is NP-complete, though in practice it might just
+ * be doable because faces are limited in size).
+ * For simplicity, we only consider *pairs* of LINE_UNKNOWNS that are
+ * known to be identical. If setting them both to YES (or NO) would break
+ * the clue, set them to NO (or YES). */
- case 1:
- if (square_setall_identical(sstate, i, j, LINE_NO))
- diff = min(diff, DIFF_EASY);
- break;
- case 3:
- if (square_setall_identical(sstate, i, j, LINE_YES))
- diff = min(diff, DIFF_EASY);
- break;
- }
+ for (i = 0; i < g->num_faces; i++) {
+ int N, yes, no, unknown;
+ int clue;
- if (SQUARE_YES_COUNT(sstate, i, j) +
- SQUARE_NO_COUNT(sstate, i, j) == 2) {
- /* There are exactly two unknown lines bordering this
- * square. */
- if (SQUARE_YES_COUNT(sstate, i, j) + 1 ==
- CLUE_AT(state, i, j)) {
- /* They must be different */
- if (square_relate_2_unknowns(sstate, i, j, TRUE))
- diff = min(diff, DIFF_HARD);
- }
- }
- }
-
- check_caches(sstate);
-
- FORALL_DOTS(state, i, j) {
- if (DOT_YES_COUNT(sstate, i, j) == 1 &&
- DOT_NO_COUNT(sstate, i, j) == 1) {
- if (dot_relate_2_unknowns(sstate, i, j, TRUE))
- diff = min(diff, DIFF_HARD);
+ if (sstate->face_solved[i])
continue;
- }
-
- if (DOT_YES_COUNT(sstate, i, j) == 0 &&
- DOT_NO_COUNT(sstate, i, j) == 2) {
- if (dot_relate_2_unknowns(sstate, i, j, FALSE))
- diff = min(diff, DIFF_HARD);
+ clue = state->clues[i];
+ if (clue < 0)
continue;
- }
- }
-
- /* If two lines into a dot are related, the other two lines into that dot
- * are related in the same way. */
-
- /* iter over points that aren't on edges */
- for (i = 1; i < w; ++i) {
- for (j = 1; j < h; ++j) {
- if (sstate->dot_solved[DOT_INDEX(state, i, j)])
- continue;
-
- /* iter over directions */
- for (dir1 = 0; dir1 < 4; ++dir1) {
- for (dir2 = dir1+1; dir2 < 4; ++dir2) {
- /* canonify both lines */
- can1 = edsf_canonify
- (sstate->hard->linedsf,
- LINEDSF_INDEX(state, i, j, dir1),
- &inv1);
- can2 = edsf_canonify
- (sstate->hard->linedsf,
- LINEDSF_INDEX(state, i, j, dir2),
- &inv2);
- /* merge opposite lines */
- if (can1 == can2) {
- if (merge_lines(sstate,
- i, j, OPP_DIR(dir1),
- i, j, OPP_DIR(dir2),
- inv1 ^ inv2)) {
- diff = min(diff, DIFF_HARD);
- }
- }
- }
- }
- }
- }
- /* If the state of a line is known, deduce the state of its canonical line
- * too. */
- FORALL_DOTS(state, i, j) {
- /* Do this even if the dot we're on is solved */
- if (i < w) {
- can1 = edsf_canonify(sstate->hard->linedsf,
- LINEDSF_INDEX(state, i, j, RIGHT),
- &inv1);
- linedsf_deindex(state, can1, &a, &b, &dir1);
- s = RIGHTOF_DOT(state, i, j);
- if (s != LINE_UNKNOWN)
- {
- if (set_line_bydot(sstate, a, b, dir1, inv1 ? OPP(s) : s))
- diff = min(diff, DIFF_EASY);
- }
+ N = g->faces[i].order;
+ yes = sstate->face_yes_count[i];
+ if (yes + 1 == clue) {
+ if (face_setall_identical(sstate, i, LINE_NO))
+ diff = min(diff, DIFF_EASY);
}
- if (j < h) {
- can1 = edsf_canonify(sstate->hard->linedsf,
- LINEDSF_INDEX(state, i, j, DOWN),
- &inv1);
- linedsf_deindex(state, can1, &a, &b, &dir1);
- s = BELOW_DOT(state, i, j);
- if (s != LINE_UNKNOWN)
- {
- if (set_line_bydot(sstate, a, b, dir1, inv1 ? OPP(s) : s))
- diff = min(diff, DIFF_EASY);
- }
+ no = sstate->face_no_count[i];
+ if (no + 1 == N - clue) {
+ if (face_setall_identical(sstate, i, LINE_YES))
+ diff = min(diff, DIFF_EASY);
}
- }
- /* Interactions between dline and linedsf */
- FORALL_DOTS(state, i, j) {
- if (sstate->dot_solved[DOT_INDEX(state, i, j)])
- continue;
-
- FORALL_DOT_DLINES(dd) {
- const struct dline dll = dlines[dd], *dl = &dll;
- if (i == 0 && (dl->dir1 == LEFT || dl->dir2 == LEFT))
+ /* Reload YES count, it might have changed */
+ yes = sstate->face_yes_count[i];
+ unknown = N - no - yes;
+
+ /* Deductions with small number of LINE_UNKNOWNs, based on overall
+ * parity of lines. */
+ diff_tmp = parity_deductions(sstate, g->faces[i].edges,
+ (clue - yes) % 2, unknown);
+ diff = min(diff, diff_tmp);
+ }
+
+ /* ------ Dot deductions ------ */
+ for (i = 0; i < g->num_dots; i++) {
+ grid_dot *d = g->dots + i;
+ int N = d->order;
+ int j;
+ int yes, no, unknown;
+ /* Go through dlines, and do any dline<->linedsf deductions wherever
+ * we find two UNKNOWNS. */
+ for (j = 0; j < N; j++) {
+ int dline_index = dline_index_from_dot(g, d, j);
+ int line1_index;
+ int line2_index;
+ int can1, can2, inv1, inv2;
+ int j2;
+ line1_index = d->edges[j] - g->edges;
+ if (state->lines[line1_index] != LINE_UNKNOWN)
continue;
- if (i == w && (dl->dir1 == RIGHT || dl->dir2 == RIGHT))
+ j2 = j + 1;
+ if (j2 == N) j2 = 0;
+ line2_index = d->edges[j2] - g->edges;
+ if (state->lines[line2_index] != LINE_UNKNOWN)
continue;
- if (j == 0 && (dl->dir1 == UP || dl->dir2 == UP))
+ /* Infer dline flags from linedsf */
+ can1 = edsf_canonify(sstate->linedsf, line1_index, &inv1);
+ can2 = edsf_canonify(sstate->linedsf, line2_index, &inv2);
+ if (can1 == can2 && inv1 != inv2) {
+ /* These are opposites, so set dline atmostone/atleastone */
+ if (set_atmostone(dlines, dline_index))
+ diff = min(diff, DIFF_NORMAL);
+ if (set_atleastone(dlines, dline_index))
+ diff = min(diff, DIFF_NORMAL);
continue;
- if (j == h && (dl->dir1 == DOWN || dl->dir2 == DOWN))
- continue;
-
- if (get_dot_dline(state, sstate->normal->dot_atleastone,
- i, j, dd) &&
- get_dot_dline(state, sstate->normal->dot_atmostone,
- i, j, dd)) {
- /* atleastone && atmostone => inverse */
- if (merge_lines(sstate, i, j, dl->dir1, i, j, dl->dir2, 1)) {
+ }
+ /* Infer linedsf from dline flags */
+ if (is_atmostone(dlines, dline_index)
+ && is_atleastone(dlines, dline_index)) {
+ if (merge_lines(sstate, line1_index, line2_index, 1))
diff = min(diff, DIFF_HARD);
- }
- } else {
- /* don't have atleastone and atmostone for this dline */
- can1 = edsf_canonify(sstate->hard->linedsf,
- LINEDSF_INDEX(state, i, j, dl->dir1),
- &inv1);
- can2 = edsf_canonify(sstate->hard->linedsf,
- LINEDSF_INDEX(state, i, j, dl->dir2),
- &inv2);
- if (can1 == can2) {
- if (inv1 == inv2) {
- /* identical => collapse dline */
- if (get_dot_dline(state,
- sstate->normal->dot_atleastone,
- i, j, dd)) {
- if (set_line_bydot(sstate, i, j,
- dl->dir1, LINE_YES)) {
- diff = min(diff, DIFF_EASY);
- }
- if (set_line_bydot(sstate, i, j,
- dl->dir2, LINE_YES)) {
- diff = min(diff, DIFF_EASY);
- }
- } else if (get_dot_dline(state,
- sstate->normal->dot_atmostone,
- i, j, dd)) {
- if (set_line_bydot(sstate, i, j,
- dl->dir1, LINE_NO)) {
- diff = min(diff, DIFF_EASY);
- }
- if (set_line_bydot(sstate, i, j,
- dl->dir2, LINE_NO)) {
- diff = min(diff, DIFF_EASY);
- }
- }
- } else {
- /* inverse => atleastone && atmostone */
- if (set_dot_dline(state,
- sstate->normal->dot_atleastone,
- i, j, dd)) {
- diff = min(diff, DIFF_NORMAL);
- }
- if (set_dot_dline(state,
- sstate->normal->dot_atmostone,
- i, j, dd)) {
- diff = min(diff, DIFF_NORMAL);
- }
- }
- }
}
}
+
+ /* Deductions with small number of LINE_UNKNOWNs, based on overall
+ * parity of lines. */
+ yes = sstate->dot_yes_count[i];
+ no = sstate->dot_no_count[i];
+ unknown = N - yes - no;
+ diff_tmp = parity_deductions(sstate, d->edges,
+ yes % 2, unknown);
+ diff = min(diff, diff_tmp);
}
-
- /* If the state of the canonical line for line 'l' is known, deduce the
- * state of 'l' */
- FORALL_DOTS(state, i, j) {
- if (sstate->dot_solved[DOT_INDEX(state, i, j)])
- continue;
- if (i < w) {
- can1 = edsf_canonify(sstate->hard->linedsf,
- LINEDSF_INDEX(state, i, j, RIGHT),
- &inv1);
- linedsf_deindex(state, can1, &a, &b, &dir1);
- s = get_line_status_from_point(state, a, b, dir1);
- if (s != LINE_UNKNOWN)
- {
- if (set_line_bydot(sstate, i, j, RIGHT, inv1 ? OPP(s) : s))
- diff = min(diff, DIFF_EASY);
- }
- }
- if (j < h) {
- can1 = edsf_canonify(sstate->hard->linedsf,
- LINEDSF_INDEX(state, i, j, DOWN),
- &inv1);
- linedsf_deindex(state, can1, &a, &b, &dir1);
- s = get_line_status_from_point(state, a, b, dir1);
- if (s != LINE_UNKNOWN)
- {
- if (set_line_bydot(sstate, i, j, DOWN, inv1 ? OPP(s) : s))
+ /* ------ Edge dsf deductions ------ */
+
+ /* If the state of a line is known, deduce the state of its canonical line
+ * too, and vice versa. */
+ for (i = 0; i < g->num_edges; i++) {
+ int can, inv;
+ enum line_state s;
+ can = edsf_canonify(sstate->linedsf, i, &inv);
+ if (can == i)
+ continue;
+ s = sstate->state->lines[can];
+ if (s != LINE_UNKNOWN) {
+ if (solver_set_line(sstate, i, inv ? OPP(s) : s))
+ diff = min(diff, DIFF_EASY);
+ } else {
+ s = sstate->state->lines[i];
+ if (s != LINE_UNKNOWN) {
+ if (solver_set_line(sstate, can, inv ? OPP(s) : s))
diff = min(diff, DIFF_EASY);
}
}
{
int edgecount = 0, clues = 0, satclues = 0, sm1clues = 0;
game_state *state = sstate->state;
- int shortest_chainlen = DOT_COUNT(state);
+ grid *g = state->game_grid;
+ int shortest_chainlen = g->num_dots;
int loop_found = FALSE;
- int d;
int dots_connected;
int progress = FALSE;
- int i, j;
+ int i;
/*
* Go through the grid and update for all the new edges.
* Since merge_dots() is idempotent, the simplest way to
* do this is just to update for _all_ the edges.
- *
- * Also, while we're here, we count the edges, count the
- * clues, count the satisfied clues, and count the
- * satisfied-minus-one clues.
+ * Also, while we're here, we count the edges.
*/
- FORALL_DOTS(state, i, j) {
- if (RIGHTOF_DOT(state, i, j) == LINE_YES) {
- loop_found |= merge_dots(sstate, i, j, i+1, j);
- edgecount++;
- }
- if (BELOW_DOT(state, i, j) == LINE_YES) {
- loop_found |= merge_dots(sstate, i, j, i, j+1);
+ for (i = 0; i < g->num_edges; i++) {
+ if (state->lines[i] == LINE_YES) {
+ loop_found |= merge_dots(sstate, i);
edgecount++;
}
+ }
- if (CLUE_AT(state, i, j) >= 0) {
- int c = CLUE_AT(state, i, j);
- int o = SQUARE_YES_COUNT(sstate, i, j);
+ /*
+ * Count the clues, count the satisfied clues, and count the
+ * satisfied-minus-one clues.
+ */
+ for (i = 0; i < g->num_faces; i++) {
+ int c = state->clues[i];
+ if (c >= 0) {
+ int o = sstate->face_yes_count[i];
if (o == c)
satclues++;
else if (o == c-1)
}
}
- for (i = 0; i < DOT_COUNT(state); ++i) {
- dots_connected =
+ for (i = 0; i < g->num_dots; ++i) {
+ dots_connected =
sstate->looplen[dsf_canonify(sstate->dotdsf, i)];
if (dots_connected > 1)
shortest_chainlen = min(shortest_chainlen, dots_connected);
sstate->solver_status = SOLVER_SOLVED;
/* This discovery clearly counts as progress, even if we haven't
* just added any lines or anything */
- progress = TRUE;
+ progress = TRUE;
goto finished_loop_deductionsing;
}
* equivalence class. If we find one, test to see if the
* loop it would create is a solution.
*/
- FORALL_DOTS(state, i, j) {
- for (d = 0; d < 2; d++) {
- int i2, j2, eqclass, val;
+ for (i = 0; i < g->num_edges; i++) {
+ grid_edge *e = g->edges + i;
+ int d1 = e->dot1 - g->dots;
+ int d2 = e->dot2 - g->dots;
+ int eqclass, val;
+ if (state->lines[i] != LINE_UNKNOWN)
+ continue;
- if (d == 0) {
- if (RIGHTOF_DOT(state, i, j) !=
- LINE_UNKNOWN)
- continue;
- i2 = i+1;
- j2 = j;
- } else {
- if (BELOW_DOT(state, i, j) !=
- LINE_UNKNOWN) {
- continue;
- }
- i2 = i;
- j2 = j+1;
- }
+ eqclass = dsf_canonify(sstate->dotdsf, d1);
+ if (eqclass != dsf_canonify(sstate->dotdsf, d2))
+ continue;
- eqclass = dsf_canonify(sstate->dotdsf, j * (state->w+1) + i);
- if (eqclass != dsf_canonify(sstate->dotdsf,
- j2 * (state->w+1) + i2)) {
- continue;
- }
+ val = LINE_NO; /* loop is bad until proven otherwise */
- val = LINE_NO; /* loop is bad until proven otherwise */
+ /*
+ * This edge would form a loop. Next
+ * question: how long would the loop be?
+ * Would it equal the total number of edges
+ * (plus the one we'd be adding if we added
+ * it)?
+ */
+ if (sstate->looplen[eqclass] == edgecount + 1) {
+ int sm1_nearby;
/*
- * This edge would form a loop. Next
- * question: how long would the loop be?
- * Would it equal the total number of edges
- * (plus the one we'd be adding if we added
- * it)?
+ * This edge would form a loop which
+ * took in all the edges in the entire
+ * grid. So now we need to work out
+ * whether it would be a valid solution
+ * to the puzzle, which means we have to
+ * check if it satisfies all the clues.
+ * This means that every clue must be
+ * either satisfied or satisfied-minus-
+ * 1, and also that the number of
+ * satisfied-minus-1 clues must be at
+ * most two and they must lie on either
+ * side of this edge.
*/
- if (sstate->looplen[eqclass] == edgecount + 1) {
- int sm1_nearby;
- int cx, cy;
-
- /*
- * This edge would form a loop which
- * took in all the edges in the entire
- * grid. So now we need to work out
- * whether it would be a valid solution
- * to the puzzle, which means we have to
- * check if it satisfies all the clues.
- * This means that every clue must be
- * either satisfied or satisfied-minus-
- * 1, and also that the number of
- * satisfied-minus-1 clues must be at
- * most two and they must lie on either
- * side of this edge.
- */
- sm1_nearby = 0;
- cx = i - (j2-j);
- cy = j - (i2-i);
- if (CLUE_AT(state, cx,cy) >= 0 &&
- square_order(state, cx,cy, LINE_YES) ==
- CLUE_AT(state, cx,cy) - 1) {
- sm1_nearby++;
- }
- if (CLUE_AT(state, i, j) >= 0 &&
- SQUARE_YES_COUNT(sstate, i, j) ==
- CLUE_AT(state, i, j) - 1) {
+ sm1_nearby = 0;
+ if (e->face1) {
+ int f = e->face1 - g->faces;
+ int c = state->clues[f];
+ if (c >= 0 && sstate->face_yes_count[f] == c - 1)
sm1_nearby++;
- }
- if (sm1clues == sm1_nearby &&
- sm1clues + satclues == clues) {
- val = LINE_YES; /* loop is good! */
- }
}
-
- /*
- * Right. Now we know that adding this edge
- * would form a loop, and we know whether
- * that loop would be a viable solution or
- * not.
- *
- * If adding this edge produces a solution,
- * then we know we've found _a_ solution but
- * we don't know that it's _the_ solution -
- * if it were provably the solution then
- * we'd have deduced this edge some time ago
- * without the need to do loop detection. So
- * in this state we return SOLVER_AMBIGUOUS,
- * which has the effect that hitting Solve
- * on a user-provided puzzle will fill in a
- * solution but using the solver to
- * construct new puzzles won't consider this
- * a reasonable deduction for the user to
- * make.
- */
- if (d == 0) {
- progress = set_line_bydot(sstate, i, j, RIGHT, val);
- assert(progress == TRUE);
- } else {
- progress = set_line_bydot(sstate, i, j, DOWN, val);
- assert(progress == TRUE);
+ if (e->face2) {
+ int f = e->face2 - g->faces;
+ int c = state->clues[f];
+ if (c >= 0 && sstate->face_yes_count[f] == c - 1)
+ sm1_nearby++;
}
- if (val == LINE_YES) {
- sstate->solver_status = SOLVER_AMBIGUOUS;
- goto finished_loop_deductionsing;
+ if (sm1clues == sm1_nearby &&
+ sm1clues + satclues == clues) {
+ val = LINE_YES; /* loop is good! */
}
}
+
+ /*
+ * Right. Now we know that adding this edge
+ * would form a loop, and we know whether
+ * that loop would be a viable solution or
+ * not.
+ *
+ * If adding this edge produces a solution,
+ * then we know we've found _a_ solution but
+ * we don't know that it's _the_ solution -
+ * if it were provably the solution then
+ * we'd have deduced this edge some time ago
+ * without the need to do loop detection. So
+ * in this state we return SOLVER_AMBIGUOUS,
+ * which has the effect that hitting Solve
+ * on a user-provided puzzle will fill in a
+ * solution but using the solver to
+ * construct new puzzles won't consider this
+ * a reasonable deduction for the user to
+ * make.
+ */
+ progress = solver_set_line(sstate, i, val);
+ assert(progress == TRUE);
+ if (val == LINE_YES) {
+ sstate->solver_status = SOLVER_AMBIGUOUS;
+ goto finished_loop_deductionsing;
+ }
}
-finished_loop_deductionsing:
+ finished_loop_deductionsing:
return progress ? DIFF_EASY : DIFF_MAX;
}
/* This will return a dynamically allocated solver_state containing the (more)
* solved grid */
-static solver_state *solve_game_rec(const solver_state *sstate_start,
- int diff)
+static solver_state *solve_game_rec(const solver_state *sstate_start)
{
- int i, j;
- int w, h;
- solver_state *sstate, *sstate_saved, *sstate_tmp;
- solver_state *sstate_rec_solved;
- int recursive_soln_count;
- int solver_progress;
- game_state *state;
-
- /* Indicates which solver we should call next. This is a sensible starting
- * point */
- int current_solver = DIFF_EASY, next_solver;
-#ifdef SHOW_WORKING
- char *text;
-#endif
-
-#if 0
- printf("solve_game_rec: recursion_remaining = %d\n",
- sstate_start->recursion_remaining);
-#endif
+ solver_state *sstate;
+ /* Index of the solver we should call next. */
+ int i = 0;
+
+ /* As a speed-optimisation, we avoid re-running solvers that we know
+ * won't make any progress. This happens when a high-difficulty
+ * solver makes a deduction that can only help other high-difficulty
+ * solvers.
+ * For example: if a new 'dline' flag is set by dline_deductions, the
+ * trivial_deductions solver cannot do anything with this information.
+ * If we've already run the trivial_deductions solver (because it's
+ * earlier in the list), there's no point running it again.
+ *
+ * Therefore: if a solver is earlier in the list than "threshold_index",
+ * we don't bother running it if it's difficulty level is less than
+ * "threshold_diff".
+ */
+ int threshold_diff = 0;
+ int threshold_index = 0;
+
sstate = dup_solver_state(sstate_start);
-
- /* Cache the values of some variables for readability */
- state = sstate->state;
- h = state->h;
- w = state->w;
-
- sstate_saved = NULL;
-
-nonrecursive_solver:
- solver_progress = FALSE;
check_caches(sstate);
- do {
-#ifdef SHOW_WORKING
- text = game_text_format(state);
- fprintf(stderr, "-----------------\n%s", text);
- sfree(text);
-#endif
-
+ while (i < NUM_SOLVERS) {
if (sstate->solver_status == SOLVER_MISTAKE)
return sstate;
-
-/* fprintf(stderr, "Invoking solver %d\n", current_solver); */
- next_solver = solver_fns[current_solver](sstate);
-
- if (next_solver == DIFF_MAX) {
-/* fprintf(stderr, "Current solver failed\n"); */
- if (current_solver < diff && current_solver + 1 < DIFF_MAX) {
- /* Try next beefier solver */
- next_solver = current_solver + 1;
- } else {
-/* fprintf(stderr, "Doing loop deductions\n"); */
- next_solver = loop_deductions(sstate);
- }
- }
-
- if (sstate->solver_status == SOLVER_SOLVED ||
+ if (sstate->solver_status == SOLVER_SOLVED ||
sstate->solver_status == SOLVER_AMBIGUOUS) {
-/* fprintf(stderr, "Solver completed\n"); */
+ /* solver finished */
break;
}
- /* Once we've looped over all permitted solvers then the loop
- * deductions without making any progress, we'll exit this while loop */
- current_solver = next_solver;
- } while (current_solver < DIFF_MAX);
+ if ((solver_diffs[i] >= threshold_diff || i >= threshold_index)
+ && solver_diffs[i] <= sstate->diff) {
+ /* current_solver is eligible, so use it */
+ int next_diff = solver_fns[i](sstate);
+ if (next_diff != DIFF_MAX) {
+ /* solver made progress, so use new thresholds and
+ * start again at top of list. */
+ threshold_diff = next_diff;
+ threshold_index = i;
+ i = 0;
+ continue;
+ }
+ }
+ /* current_solver is ineligible, or failed to make progress, so
+ * go to the next solver in the list */
+ i++;
+ }
if (sstate->solver_status == SOLVER_SOLVED ||
sstate->solver_status == SOLVER_AMBIGUOUS) {
/* s/LINE_UNKNOWN/LINE_NO/g */
- array_setall(sstate->state->hl, LINE_UNKNOWN, LINE_NO,
- HL_COUNT(sstate->state));
- array_setall(sstate->state->vl, LINE_UNKNOWN, LINE_NO,
- VL_COUNT(sstate->state));
+ array_setall(sstate->state->lines, LINE_UNKNOWN, LINE_NO,
+ sstate->state->game_grid->num_edges);
return sstate;
}
- /* Perform recursive calls */
- if (sstate->recursion_remaining) {
- sstate_saved = dup_solver_state(sstate);
-
- sstate->recursion_remaining--;
-
- recursive_soln_count = 0;
- sstate_rec_solved = NULL;
-
- /* Memory management:
- * sstate_saved won't be modified but needs to be freed when we have
- * finished with it.
- * sstate is expected to contain our 'best' solution by the time we
- * finish this section of code. It's the thing we'll try adding lines
- * to, seeing if they make it more solvable.
- * If sstate_rec_solved is non-NULL, it will supersede sstate
- * eventually. sstate_tmp should not hold a value persistently.
- */
-
- /* NB SOLVER_AMBIGUOUS is like SOLVER_SOLVED except the solver is aware
- * of the possibility of additional solutions. So as soon as we have a
- * SOLVER_AMBIGUOUS we can safely propagate it back to our caller, but
- * if we get a SOLVER_SOLVED we want to keep trying in case we find
- * further solutions and have to mark it ambiguous.
- */
-
-#define DO_RECURSIVE_CALL(dir_dot) \
- if (dir_dot(sstate->state, i, j) == LINE_UNKNOWN) { \
- debug(("Trying " #dir_dot " at [%d,%d]\n", i, j)); \
- LV_##dir_dot(sstate->state, i, j) = LINE_YES; \
- sstate_tmp = solve_game_rec(sstate, diff); \
- switch (sstate_tmp->solver_status) { \
- case SOLVER_AMBIGUOUS: \
- debug(("Solver ambiguous, returning\n")); \
- sstate_rec_solved = sstate_tmp; \
- goto finished_recursion; \
- case SOLVER_SOLVED: \
- switch (++recursive_soln_count) { \
- case 1: \
- debug(("One solution found\n")); \
- sstate_rec_solved = sstate_tmp; \
- break; \
- case 2: \
- debug(("Ambiguous solutions found\n")); \
- free_solver_state(sstate_tmp); \
- sstate_rec_solved->solver_status = SOLVER_AMBIGUOUS; \
- goto finished_recursion; \
- default: \
- assert(!"recursive_soln_count out of range"); \
- break; \
- } \
- break; \
- case SOLVER_MISTAKE: \
- debug(("Non-solution found\n")); \
- free_solver_state(sstate_tmp); \
- free_solver_state(sstate_saved); \
- LV_##dir_dot(sstate->state, i, j) = LINE_NO; \
- goto nonrecursive_solver; \
- case SOLVER_INCOMPLETE: \
- debug(("Recursive step inconclusive\n")); \
- free_solver_state(sstate_tmp); \
- break; \
- } \
- free_solver_state(sstate); \
- sstate = dup_solver_state(sstate_saved); \
- }
-
- FORALL_DOTS(state, i, j) {
- /* Only perform recursive calls on 'loose ends' */
- if (DOT_YES_COUNT(sstate, i, j) == 1) {
- DO_RECURSIVE_CALL(LEFTOF_DOT);
- DO_RECURSIVE_CALL(RIGHTOF_DOT);
- DO_RECURSIVE_CALL(ABOVE_DOT);
- DO_RECURSIVE_CALL(BELOW_DOT);
- }
- }
-
-finished_recursion:
-
- if (sstate_rec_solved) {
- free_solver_state(sstate);
- sstate = sstate_rec_solved;
- }
- }
-
return sstate;
}
-#if 0
-#define HANDLE_DLINE(dline, dir1_sq, dir2_sq, a, b) \
- if (sstate->normal->dot_atmostone[i+a + (sstate->state->w + 1) * (j+b)] & \
- 1<<dline) { \
- if (square_order(sstate->state, i, j, LINE_UNKNOWN) - 1 == \
- CLUE_AT(sstate->state, i, j) - '0') { \
- square_setall(sstate->state, i, j, LINE_UNKNOWN, LINE_YES); \
- /* XXX the following may overwrite known data! */ \
- dir1_sq(sstate->state, i, j) = LINE_UNKNOWN; \
- dir2_sq(sstate->state, i, j) = LINE_UNKNOWN; \
- } \
- }
- SQUARE_DLINES;
-#undef HANDLE_DLINE
-#endif
-
-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;
sstate = new_solver_state(state, DIFF_MAX);
- new_sstate = solve_game_rec(sstate, DIFF_MAX);
+ new_sstate = solve_game_rec(sstate);
if (new_sstate->solver_status == SOLVER_SOLVED) {
soln = encode_solve_move(new_sstate->state);
* 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)
{
- int hl_selected;
- int i, j, p, q;
+ grid *g = state->game_grid;
+ grid_edge *e;
+ int i;
char *ret, buf[80];
char button_char = ' ';
enum line_state old_state;
button &= ~MOD_MASK;
- /* Around each line is a diamond-shaped region where points within that
- * region are closer to this line than any other. We assume any click
- * within a line's diamond was meant for that line. It would all be a lot
- * simpler if the / and % operators respected modulo arithmetic properly
- * for negative numbers. */
-
- x -= BORDER;
- y -= BORDER;
-
- /* Get the coordinates of the square the click was in */
- i = (x + TILE_SIZE) / TILE_SIZE - 1;
- j = (y + TILE_SIZE) / TILE_SIZE - 1;
-
- /* Get the precise position inside square [i,j] */
- p = (x + TILE_SIZE) % TILE_SIZE;
- q = (y + TILE_SIZE) % TILE_SIZE;
-
- /* After this bit of magic [i,j] will correspond to the point either above
- * or to the left of the line selected */
- if (p > q) {
- if (TILE_SIZE - p > q) {
- hl_selected = TRUE;
- } else {
- hl_selected = FALSE;
- ++i;
- }
- } else {
- if (TILE_SIZE - q > p) {
- hl_selected = FALSE;
- } else {
- hl_selected = TRUE;
- ++j;
- }
- }
+ /* Convert mouse-click (x,y) to grid coordinates */
+ x -= BORDER(ds->tilesize);
+ y -= BORDER(ds->tilesize);
+ x = x * g->tilesize / ds->tilesize;
+ y = y * g->tilesize / ds->tilesize;
+ x += g->lowest_x;
+ y += g->lowest_y;
- if (i < 0 || j < 0)
+ e = grid_nearest_edge(g, x, y);
+ if (e == NULL)
return NULL;
- if (hl_selected) {
- if (i >= state->w || j >= state->h + 1)
- return NULL;
- } else {
- if (i >= state->w + 1 || j >= state->h)
- return NULL;
- }
+ i = e - g->edges;
/* I think it's only possible to play this game with mouse clicks, sorry */
/* Maybe will add mouse drag support some time */
- if (hl_selected)
- old_state = RIGHTOF_DOT(state, i, j);
- else
- old_state = BELOW_DOT(state, i, j);
+ old_state = state->lines[i];
switch (button) {
- case LEFT_BUTTON:
- switch (old_state) {
- case LINE_UNKNOWN:
- button_char = 'y';
- break;
- case LINE_YES:
- case LINE_NO:
- button_char = 'u';
- break;
- }
- break;
- case MIDDLE_BUTTON:
- button_char = 'u';
- break;
- case RIGHT_BUTTON:
- switch (old_state) {
- case LINE_UNKNOWN:
- button_char = 'n';
- break;
- case LINE_NO:
- case LINE_YES:
- button_char = 'u';
- break;
- }
- break;
- default:
- return NULL;
+ case LEFT_BUTTON:
+ switch (old_state) {
+ case LINE_UNKNOWN:
+ button_char = 'y';
+ break;
+ case LINE_YES:
+#ifdef STYLUS_BASED
+ button_char = 'n';
+ break;
+#endif
+ case LINE_NO:
+ button_char = 'u';
+ break;
+ }
+ break;
+ case MIDDLE_BUTTON:
+ button_char = 'u';
+ break;
+ case RIGHT_BUTTON:
+ switch (old_state) {
+ case LINE_UNKNOWN:
+ button_char = 'n';
+ break;
+ case LINE_NO:
+#ifdef STYLUS_BASED
+ button_char = 'y';
+ break;
+#endif
+ case LINE_YES:
+ button_char = 'u';
+ break;
+ }
+ break;
+ default:
+ return NULL;
}
- sprintf(buf, "%d,%d%c%c", i, j, (int)(hl_selected ? 'h' : 'v'), (int)button_char);
+ sprintf(buf, "%d%c", i, (int)button_char);
ret = dupstr(buf);
return ret;
}
-static game_state *execute_move(game_state *state, char *move)
+static game_state *execute_move(const game_state *state, const char *move)
{
- int i, j;
+ int i;
game_state *newstate = dup_game(state);
if (move[0] == 'S') {
while (*move) {
i = atoi(move);
- move = strchr(move, ',');
- if (!move)
+ if (i < 0 || i >= newstate->game_grid->num_edges)
goto fail;
- j = atoi(++move);
move += strspn(move, "1234567890");
switch (*(move++)) {
- case 'h':
- if (i >= newstate->w || j > newstate->h)
- goto fail;
- switch (*(move++)) {
- case 'y':
- LV_RIGHTOF_DOT(newstate, i, j) = LINE_YES;
- break;
- case 'n':
- LV_RIGHTOF_DOT(newstate, i, j) = LINE_NO;
- break;
- case 'u':
- LV_RIGHTOF_DOT(newstate, i, j) = LINE_UNKNOWN;
- break;
- default:
- goto fail;
- }
- break;
- case 'v':
- if (i > newstate->w || j >= newstate->h)
- goto fail;
- switch (*(move++)) {
- case 'y':
- LV_BELOW_DOT(newstate, i, j) = LINE_YES;
- break;
- case 'n':
- LV_BELOW_DOT(newstate, i, j) = LINE_NO;
- break;
- case 'u':
- LV_BELOW_DOT(newstate, i, j) = LINE_UNKNOWN;
- break;
- default:
- goto fail;
- }
- break;
- default:
- goto fail;
+ case 'y':
+ newstate->lines[i] = LINE_YES;
+ break;
+ case 'n':
+ newstate->lines[i] = LINE_NO;
+ break;
+ case 'u':
+ newstate->lines[i] = LINE_UNKNOWN;
+ break;
+ default:
+ goto fail;
}
}
/*
* Check for completion.
*/
- i = 0; /* placate optimiser */
- for (j = 0; j <= newstate->h; j++) {
- for (i = 0; i < newstate->w; i++)
- if (LV_RIGHTOF_DOT(newstate, i, j) == LINE_YES)
- break;
- if (i < newstate->w)
- break;
+ if (check_completion(newstate))
+ newstate->solved = TRUE;
+
+ return newstate;
+
+ fail:
+ free_game(newstate);
+ return NULL;
+}
+
+/* ----------------------------------------------------------------------
+ * Drawing routines.
+ */
+
+/* Convert from grid coordinates to screen coordinates */
+static void grid_to_screen(const game_drawstate *ds, const grid *g,
+ int grid_x, int grid_y, int *x, int *y)
+{
+ *x = grid_x - g->lowest_x;
+ *y = grid_y - g->lowest_y;
+ *x = *x * ds->tilesize / g->tilesize;
+ *y = *y * ds->tilesize / g->tilesize;
+ *x += BORDER(ds->tilesize);
+ *y += BORDER(ds->tilesize);
+}
+
+/* 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,
+ grid_face *f, int *xret, int *yret)
+{
+ int faceindex = f - g->faces;
+
+ /*
+ * Return the cached position for this face, if we've already
+ * worked it out.
+ */
+ if (ds->textx[faceindex] >= 0) {
+ *xret = ds->textx[faceindex];
+ *yret = ds->texty[faceindex];
+ return;
}
- if (j <= newstate->h) {
- int prevdir = 'R';
- int x = i, y = j;
- int looplen, count;
- /*
- * We've found a horizontal edge at (i,j). Follow it round
- * to see if it's part of a loop.
- */
- looplen = 0;
- while (1) {
- int order = dot_order(newstate, x, y, LINE_YES);
- if (order != 2)
- goto completion_check_done;
-
- if (LEFTOF_DOT(newstate, x, y) == LINE_YES && prevdir != 'L') {
- x--;
- prevdir = 'R';
- } else if (RIGHTOF_DOT(newstate, x, y) == LINE_YES &&
- prevdir != 'R') {
- x++;
- prevdir = 'L';
- } else if (ABOVE_DOT(newstate, x, y) == LINE_YES &&
- prevdir != 'U') {
- y--;
- prevdir = 'D';
- } else if (BELOW_DOT(newstate, x, y) == LINE_YES &&
- prevdir != 'D') {
- y++;
- prevdir = 'U';
- } else {
- assert(!"Can't happen"); /* dot_order guarantees success */
- }
+ /*
+ * Otherwise, use the incentre computed by grid.c and convert it
+ * to screen coordinates.
+ */
+ grid_find_incentre(f);
+ grid_to_screen(ds, g, f->ix, f->iy,
+ &ds->textx[faceindex], &ds->texty[faceindex]);
- looplen++;
+ *xret = ds->textx[faceindex];
+ *yret = ds->texty[faceindex];
+}
- if (x == i && y == j)
- break;
- }
+static void face_text_bbox(game_drawstate *ds, grid *g, grid_face *f,
+ int *x, int *y, int *w, int *h)
+{
+ int xx, yy;
+ face_text_pos(ds, g, f, &xx, &yy);
- if (x != i || y != j || looplen == 0)
- goto completion_check_done;
+ /* There seems to be a certain amount of trial-and-error involved
+ * in working out the correct bounding-box for the text. */
- /*
- * We've traced our way round a loop, and we know how many
- * line segments were involved. Count _all_ the line
- * segments in the grid, to see if the loop includes them
- * all.
- */
- count = 0;
- FORALL_DOTS(newstate, i, j) {
- count += ((RIGHTOF_DOT(newstate, i, j) == LINE_YES) +
- (BELOW_DOT(newstate, i, j) == LINE_YES));
- }
- assert(count >= looplen);
- if (count != looplen)
- goto completion_check_done;
+ *x = xx - ds->tilesize/4 - 1;
+ *y = yy - ds->tilesize/4 - 3;
+ *w = ds->tilesize/2 + 2;
+ *h = ds->tilesize/2 + 5;
+}
- /*
- * The grid contains one closed loop and nothing else.
- * Check that all the clues are satisfied.
- */
- FORALL_SQUARES(newstate, i, j) {
- if (CLUE_AT(newstate, i, j) >= 0) {
- if (square_order(newstate, i, j, LINE_YES) !=
- CLUE_AT(newstate, i, j)) {
- goto completion_check_done;
- }
- }
- }
+static void game_redraw_clue(drawing *dr, game_drawstate *ds,
+ const game_state *state, int i)
+{
+ grid *g = state->game_grid;
+ grid_face *f = g->faces + i;
+ int x, y;
+ char c[20];
- /*
- * Completed!
- */
- newstate->solved = TRUE;
+ sprintf(c, "%d", state->clues[i]);
+
+ face_text_pos(ds, g, f, &x, &y);
+ draw_text(dr, x, y,
+ FONT_VARIABLE, ds->tilesize/2,
+ ALIGN_VCENTRE | ALIGN_HCENTRE,
+ ds->clue_error[i] ? COL_MISTAKE :
+ ds->clue_satisfied[i] ? COL_SATISFIED : COL_FOREGROUND, c);
+}
+
+static void edge_bbox(game_drawstate *ds, grid *g, grid_edge *e,
+ int *x, int *y, int *w, int *h)
+{
+ int x1 = e->dot1->x;
+ int y1 = e->dot1->y;
+ int x2 = e->dot2->x;
+ int y2 = e->dot2->y;
+ int xmin, xmax, ymin, ymax;
+
+ grid_to_screen(ds, g, x1, y1, &x1, &y1);
+ grid_to_screen(ds, g, x2, y2, &x2, &y2);
+ /* Allow extra margin for dots, and thickness of lines */
+ xmin = min(x1, x2) - 2;
+ xmax = max(x1, x2) + 2;
+ ymin = min(y1, y2) - 2;
+ ymax = max(y1, y2) + 2;
+
+ *x = xmin;
+ *y = ymin;
+ *w = xmax - xmin + 1;
+ *h = ymax - ymin + 1;
+}
+
+static void dot_bbox(game_drawstate *ds, grid *g, grid_dot *d,
+ int *x, int *y, int *w, int *h)
+{
+ int x1, y1;
+
+ grid_to_screen(ds, g, d->x, d->y, &x1, &y1);
+
+ *x = x1 - 2;
+ *y = y1 - 2;
+ *w = 5;
+ *h = 5;
+}
+
+static const int loopy_line_redraw_phases[] = {
+ COL_FAINT, COL_LINEUNKNOWN, COL_FOREGROUND, COL_HIGHLIGHT, COL_MISTAKE
+};
+#define NPHASES lenof(loopy_line_redraw_phases)
+
+static void game_redraw_line(drawing *dr, game_drawstate *ds,
+ 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 line_colour;
+
+ if (state->line_errors[i])
+ line_colour = COL_MISTAKE;
+ else if (state->lines[i] == LINE_UNKNOWN)
+ line_colour = COL_LINEUNKNOWN;
+ else if (state->lines[i] == LINE_NO)
+ line_colour = COL_FAINT;
+ else if (ds->flashing)
+ line_colour = COL_HIGHLIGHT;
+ else
+ line_colour = COL_FOREGROUND;
+ if (line_colour != loopy_line_redraw_phases[phase])
+ return;
+
+ /* Convert from grid to screen coordinates */
+ 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);
+
+ if (line_colour == COL_FAINT) {
+ static int draw_faint_lines = -1;
+ if (draw_faint_lines < 0) {
+ char *env = getenv("LOOPY_FAINT_LINES");
+ draw_faint_lines = (!env || (env[0] == 'y' ||
+ env[0] == 'Y'));
+ }
+ if (draw_faint_lines)
+ draw_line(dr, x1, y1, x2, y2, line_colour);
+ } else {
+ draw_thick_line(dr, 3.0,
+ x1 + 0.5, y1 + 0.5,
+ x2 + 0.5, y2 + 0.5,
+ line_colour);
}
+}
-completion_check_done:
- return newstate;
+static void game_redraw_dot(drawing *dr, game_drawstate *ds,
+ const game_state *state, int i)
+{
+ grid *g = state->game_grid;
+ grid_dot *d = g->dots + i;
+ int x, y;
-fail:
- free_game(newstate);
- return NULL;
+ grid_to_screen(ds, g, d->x, d->y, &x, &y);
+ draw_circle(dr, x, y, 2, COL_FOREGROUND, COL_FOREGROUND);
}
-/* ----------------------------------------------------------------------
- * Drawing routines.
- */
-static void game_redraw(drawing *dr, game_drawstate *ds, game_state *oldstate,
- game_state *state, int dir, game_ui *ui,
+static int boxes_intersect(int x0, int y0, int w0, int h0,
+ int x1, int y1, int w1, int h1)
+{
+ /*
+ * Two intervals intersect iff neither is wholly on one side of
+ * the other. Two boxes intersect iff their horizontal and
+ * vertical intervals both intersect.
+ */
+ return (x0 < x1+w1 && x1 < x0+w0 && y0 < y1+h1 && y1 < y0+h0);
+}
+
+static void game_redraw_in_rect(drawing *dr, game_drawstate *ds,
+ const game_state *state,
+ int x, int y, int w, int h)
+{
+ grid *g = state->game_grid;
+ int i, phase;
+ int bx, by, bw, bh;
+
+ clip(dr, x, y, w, h);
+ draw_rect(dr, x, y, w, h, COL_BACKGROUND);
+
+ for (i = 0; i < g->num_faces; 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++) {
+ edge_bbox(ds, g, &g->edges[i], &bx, &by, &bw, &bh);
+ if (boxes_intersect(x, y, w, h, bx, by, bw, bh))
+ game_redraw_line(dr, ds, state, i, phase);
+ }
+ }
+ for (i = 0; i < g->num_dots; i++) {
+ dot_bbox(ds, g, &g->dots[i], &bx, &by, &bw, &bh);
+ if (boxes_intersect(x, y, w, h, bx, by, bw, bh))
+ game_redraw_dot(dr, ds, state, i);
+ }
+
+ unclip(dr);
+ draw_update(dr, x, y, w, h);
+}
+
+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)
{
- int i, j, n;
- char c[2];
- int line_colour, flash_changed;
- int clue_mistake;
+#define REDRAW_OBJECTS_LIMIT 16 /* Somewhat arbitrary tradeoff */
+
+ grid *g = state->game_grid;
+ int border = BORDER(ds->tilesize);
+ int i;
+ int flash_changed;
+ int redraw_everything = FALSE;
+
+ int edges[REDRAW_OBJECTS_LIMIT], nedges = 0;
+ int faces[REDRAW_OBJECTS_LIMIT], nfaces = 0;
+
+ /* Redrawing is somewhat involved.
+ *
+ * An update can theoretically affect an arbitrary number of edges
+ * (consider, for example, completing or breaking a cycle which doesn't
+ * satisfy all the clues -- we'll switch many edges between error and
+ * normal states). On the other hand, redrawing the whole grid takes a
+ * while, making the game feel sluggish, and many updates are actually
+ * quite well localized.
+ *
+ * This redraw algorithm attempts to cope with both situations gracefully
+ * and correctly. For localized changes, we set a clip rectangle, fill
+ * it with background, and then redraw (a plausible but conservative
+ * guess at) the objects which intersect the rectangle; if several
+ * objects need redrawing, we'll do them individually. However, if lots
+ * of objects are affected, we'll just redraw everything.
+ *
+ * The reason for all of this is that it's just not safe to do the redraw
+ * piecemeal. If you try to draw an antialiased diagonal line over
+ * itself, you get a slightly thicker antialiased diagonal line, which
+ * looks rather ugly after a while.
+ *
+ * So, we take two passes over the grid. The first attempts to work out
+ * what needs doing, and the second actually does it.
+ */
if (!ds->started) {
+ redraw_everything = TRUE;
/*
- * The initial contents of the window are not guaranteed and
- * can vary with front ends. To be on the safe side, all games
- * should start by drawing a big background-colour rectangle
- * covering the whole window.
+ * But we must still go through the upcoming loops, so that we
+ * set up stuff in ds correctly for the initial redraw.
*/
- draw_rect(dr, 0, 0, SIZE(state->w), SIZE(state->h), COL_BACKGROUND);
-
- /* Draw dots */
- FORALL_DOTS(state, i, j) {
- draw_rect(dr,
- BORDER + i * TILE_SIZE - LINEWIDTH/2,
- BORDER + j * TILE_SIZE - LINEWIDTH/2,
- LINEWIDTH, LINEWIDTH, COL_FOREGROUND);
+ }
+
+ /* 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;
+
+ 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);
}
- /* Draw clues */
- FORALL_SQUARES(state, i, j) {
- c[0] = CLUE2CHAR(CLUE_AT(state, i, j));
- c[1] = '\0';
- draw_text(dr,
- BORDER + i * TILE_SIZE + TILE_SIZE/2,
- BORDER + j * TILE_SIZE + TILE_SIZE/2,
- FONT_VARIABLE, TILE_SIZE/2,
- ALIGN_VCENTRE | ALIGN_HCENTRE, COL_FOREGROUND, c);
+ 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;
}
- draw_update(dr, 0, 0,
- state->w * TILE_SIZE + 2*BORDER + 1,
- state->h * TILE_SIZE + 2*BORDER + 1);
- ds->started = TRUE;
}
- if (flashtime > 0 &&
+ /* 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;
- line_colour = COL_HIGHLIGHT;
} else {
flash_changed = ds->flashing;
ds->flashing = FALSE;
- line_colour = COL_FOREGROUND;
}
-#define CROSS_SIZE (3 * LINEWIDTH / 2)
-
- /* Redraw clue colours if necessary */
- FORALL_SQUARES(state, i, j) {
- n = CLUE_AT(state, i, j);
- if (n < 0)
- continue;
-
- assert(n >= 0 && n <= 4);
-
- c[0] = CLUE2CHAR(CLUE_AT(state, i, j));
- c[1] = '\0';
-
- clue_mistake = (square_order(state, i, j, LINE_YES) > n ||
- square_order(state, i, j, LINE_NO ) > (4-n));
-
- if (clue_mistake != ds->clue_error[SQUARE_INDEX(state, i, j)]) {
- draw_rect(dr,
- BORDER + i * TILE_SIZE + CROSS_SIZE,
- BORDER + j * TILE_SIZE + CROSS_SIZE,
- TILE_SIZE - CROSS_SIZE * 2, TILE_SIZE - CROSS_SIZE * 2,
- COL_BACKGROUND);
- draw_text(dr,
- BORDER + i * TILE_SIZE + TILE_SIZE/2,
- BORDER + j * TILE_SIZE + TILE_SIZE/2,
- FONT_VARIABLE, TILE_SIZE/2,
- ALIGN_VCENTRE | ALIGN_HCENTRE,
- clue_mistake ? COL_MISTAKE : COL_FOREGROUND, c);
- draw_update(dr, i * TILE_SIZE + BORDER, j * TILE_SIZE + BORDER,
- TILE_SIZE, TILE_SIZE);
-
- ds->clue_error[SQUARE_INDEX(state, i, j)] = clue_mistake;
+ /* 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;
}
}
- /* I've also had a request to colour lines red if they make a non-solution
- * loop, or if more than two lines go into any point. I think that would
- * be good some time. */
+ /* Pass one is now done. Now we do the actual drawing. */
+ if (redraw_everything) {
+ int grid_width = g->highest_x - g->lowest_x;
+ int grid_height = g->highest_y - g->lowest_y;
+ int w = grid_width * ds->tilesize / g->tilesize;
+ int h = grid_height * ds->tilesize / g->tilesize;
-#define CLEAR_VL(i, j) \
- do { \
- draw_rect(dr, \
- BORDER + i * TILE_SIZE - CROSS_SIZE, \
- BORDER + j * TILE_SIZE + LINEWIDTH - LINEWIDTH/2, \
- CROSS_SIZE * 2, \
- TILE_SIZE - LINEWIDTH, \
- COL_BACKGROUND); \
- draw_update(dr, \
- BORDER + i * TILE_SIZE - CROSS_SIZE, \
- BORDER + j * TILE_SIZE - CROSS_SIZE, \
- CROSS_SIZE*2, \
- TILE_SIZE + CROSS_SIZE*2); \
- } while (0)
+ game_redraw_in_rect(dr, ds, state,
+ 0, 0, w + 2*border + 1, h + 2*border + 1);
+ } else {
-#define CLEAR_HL(i, j) \
- do { \
- draw_rect(dr, \
- BORDER + i * TILE_SIZE + LINEWIDTH - LINEWIDTH/2, \
- BORDER + j * TILE_SIZE - CROSS_SIZE, \
- TILE_SIZE - LINEWIDTH, \
- CROSS_SIZE * 2, \
- COL_BACKGROUND); \
- draw_update(dr, \
- BORDER + i * TILE_SIZE - CROSS_SIZE, \
- BORDER + j * TILE_SIZE - CROSS_SIZE, \
- TILE_SIZE + CROSS_SIZE*2, \
- CROSS_SIZE*2); \
- } while (0)
+ /* Right. Now we roll up our sleeves. */
- /* Vertical lines */
- FORALL_VL(state, i, j) {
- switch (BELOW_DOT(state, i, j)) {
- case LINE_UNKNOWN:
- if (ds->vl[VL_INDEX(state, i, j)] != BELOW_DOT(state, i, j)) {
- CLEAR_VL(i, j);
- }
- break;
- case LINE_YES:
- if (ds->vl[VL_INDEX(state, i, j)] != BELOW_DOT(state, i, j) ||
- flash_changed) {
- CLEAR_VL(i, j);
- draw_rect(dr,
- BORDER + i * TILE_SIZE - LINEWIDTH/2,
- BORDER + j * TILE_SIZE + LINEWIDTH - LINEWIDTH/2,
- LINEWIDTH, TILE_SIZE - LINEWIDTH,
- line_colour);
- }
- break;
- case LINE_NO:
- if (ds->vl[VL_INDEX(state, i, j)] != BELOW_DOT(state, i, j)) {
- CLEAR_VL(i, j);
- draw_line(dr,
- BORDER + i * TILE_SIZE - CROSS_SIZE,
- BORDER + j * TILE_SIZE + TILE_SIZE/2 - CROSS_SIZE,
- BORDER + i * TILE_SIZE + CROSS_SIZE - 1,
- BORDER + j * TILE_SIZE + TILE_SIZE/2 + CROSS_SIZE - 1,
- COL_FOREGROUND);
- draw_line(dr,
- BORDER + i * TILE_SIZE + CROSS_SIZE - 1,
- BORDER + j * TILE_SIZE + TILE_SIZE/2 - CROSS_SIZE,
- BORDER + i * TILE_SIZE - CROSS_SIZE,
- BORDER + j * TILE_SIZE + TILE_SIZE/2 + CROSS_SIZE - 1,
- COL_FOREGROUND);
- }
- break;
- }
- ds->vl[VL_INDEX(state, i, j)] = BELOW_DOT(state, i, j);
- }
+ for (i = 0; i < nfaces; i++) {
+ grid_face *f = g->faces + faces[i];
+ int x, y, w, h;
- /* Horizontal lines */
- FORALL_HL(state, i, j) {
- switch (RIGHTOF_DOT(state, i, j)) {
- case LINE_UNKNOWN:
- if (ds->hl[HL_INDEX(state, i, j)] != RIGHTOF_DOT(state, i, j)) {
- CLEAR_HL(i, j);
- }
- break;
- case LINE_YES:
- if (ds->hl[HL_INDEX(state, i, j)] != RIGHTOF_DOT(state, i, j) ||
- flash_changed) {
- CLEAR_HL(i, j);
- draw_rect(dr,
- BORDER + i * TILE_SIZE + LINEWIDTH - LINEWIDTH/2,
- BORDER + j * TILE_SIZE - LINEWIDTH/2,
- TILE_SIZE - LINEWIDTH, LINEWIDTH,
- line_colour);
- }
- break;
- case LINE_NO:
- if (ds->hl[HL_INDEX(state, i, j)] != RIGHTOF_DOT(state, i, j)) {
- CLEAR_HL(i, j);
- draw_line(dr,
- BORDER + i * TILE_SIZE + TILE_SIZE/2 - CROSS_SIZE,
- BORDER + j * TILE_SIZE + CROSS_SIZE - 1,
- BORDER + i * TILE_SIZE + TILE_SIZE/2 + CROSS_SIZE - 1,
- BORDER + j * TILE_SIZE - CROSS_SIZE,
- COL_FOREGROUND);
- draw_line(dr,
- BORDER + i * TILE_SIZE + TILE_SIZE/2 - CROSS_SIZE,
- BORDER + j * TILE_SIZE - CROSS_SIZE,
- BORDER + i * TILE_SIZE + TILE_SIZE/2 + CROSS_SIZE - 1,
- BORDER + j * TILE_SIZE + CROSS_SIZE - 1,
- COL_FOREGROUND);
- break;
- }
- }
- ds->hl[HL_INDEX(state, i, j)] = RIGHTOF_DOT(state, i, j);
+ face_text_bbox(ds, g, f, &x, &y, &w, &h);
+ game_redraw_in_rect(dr, ds, state, x, y, w, h);
+ }
+
+ for (i = 0; i < nedges; i++) {
+ grid_edge *e = g->edges + edges[i];
+ int x, y, w, h;
+
+ edge_bbox(ds, g, e, &x, &y, &w, &h);
+ game_redraw_in_rect(dr, ds, state, x, y, w, h);
+ }
}
+
+ 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) {
return 0.0F;
}
-static void game_print_size(game_params *params, float *x, float *y)
+static int game_status(const game_state *state)
+{
+ return state->solved ? +1 : 0;
+}
+
+static void game_print_size(const game_params *params, float *x, float *y)
{
int pw, ph;
/*
- * I'll use 7mm squares by default.
+ * I'll use 7mm "squares" by default.
*/
game_compute_size(params, 700, &pw, &ph);
*x = pw / 100.0F;
*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 x, y;
+ int i;
game_drawstate ads, *ds = &ads;
+ grid *g = state->game_grid;
- game_set_size(dr, ds, NULL, tilesize);
+ 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;
- /*
- * Dots. I'll deliberately make the dots a bit wider than the
- * lines, so you can still see them. (And also because it's
- * annoyingly tricky to make them _exactly_ the same size...)
- */
- FORALL_DOTS(state, x, y) {
- draw_circle(dr, BORDER + x * TILE_SIZE, BORDER + y * TILE_SIZE,
- LINEWIDTH, ink, ink);
+ for (i = 0; i < g->num_dots; i++) {
+ int x, y;
+ grid_to_screen(ds, g, g->dots[i].x, g->dots[i].y, &x, &y);
+ draw_circle(dr, x, y, ds->tilesize / 15, ink, ink);
}
/*
* Clues.
*/
- FORALL_SQUARES(state, x, y) {
- if (CLUE_AT(state, x, y) >= 0) {
- char c[2];
-
- c[0] = CLUE2CHAR(CLUE_AT(state, x, y));
- c[1] = '\0';
- draw_text(dr,
- BORDER + x * TILE_SIZE + TILE_SIZE/2,
- BORDER + y * TILE_SIZE + TILE_SIZE/2,
- FONT_VARIABLE, TILE_SIZE/2,
+ for (i = 0; i < g->num_faces; i++) {
+ grid_face *f = g->faces + i;
+ int clue = state->clues[i];
+ if (clue >= 0) {
+ char c[20];
+ int x, y;
+ sprintf(c, "%d", state->clues[i]);
+ face_text_pos(ds, g, f, &x, &y);
+ draw_text(dr, x, y,
+ FONT_VARIABLE, ds->tilesize / 2,
ALIGN_VCENTRE | ALIGN_HCENTRE, ink, c);
}
}
/*
- * Lines. (At the moment, I'm not bothering with crosses.)
+ * Lines.
*/
- FORALL_HL(state, x, y) {
- if (RIGHTOF_DOT(state, x, y) == LINE_YES)
- draw_rect(dr, BORDER + x * TILE_SIZE,
- BORDER + y * TILE_SIZE - LINEWIDTH/2,
- TILE_SIZE, (LINEWIDTH/2) * 2 + 1, ink);
+ for (i = 0; i < g->num_edges; i++) {
+ int thickness = (state->lines[i] == LINE_YES) ? 30 : 150;
+ grid_edge *e = g->edges + i;
+ int x1, y1, x2, y2;
+ 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);
+ if (state->lines[i] == LINE_YES)
+ {
+ /* (dx, dy) points from (x1, y1) to (x2, y2).
+ * The line is then "fattened" in a perpendicular
+ * direction to create a thin rectangle. */
+ double d = sqrt(SQ((double)x1 - x2) + SQ((double)y1 - y2));
+ double dx = (x2 - x1) / d;
+ double dy = (y2 - y1) / d;
+ int points[8];
+
+ dx = (dx * ds->tilesize) / thickness;
+ dy = (dy * ds->tilesize) / thickness;
+ points[0] = x1 + (int)dy;
+ points[1] = y1 - (int)dx;
+ points[2] = x1 - (int)dy;
+ points[3] = y1 + (int)dx;
+ points[4] = x2 - (int)dy;
+ points[5] = y2 + (int)dx;
+ points[6] = x2 + (int)dy;
+ points[7] = y2 - (int)dx;
+ draw_polygon(dr, points, 4, ink, ink);
+ }
+ else
+ {
+ /* Draw a dotted line */
+ int divisions = 6;
+ int j;
+ for (j = 1; j < divisions; j++) {
+ /* Weighted average */
+ int x = (x1 * (divisions -j) + x2 * j) / divisions;
+ int y = (y1 * (divisions -j) + y2 * j) / divisions;
+ draw_circle(dr, x, y, ds->tilesize / thickness, ink, ink);
+ }
+ }
}
- FORALL_VL(state, x, y) {
- if (BELOW_DOT(state, x, y) == LINE_YES)
- draw_rect(dr, BORDER + x * TILE_SIZE - LINEWIDTH/2,
- BORDER + y * TILE_SIZE,
- (LINEWIDTH/2) * 2 + 1, TILE_SIZE, ink);
- }
+ sfree(ds->textx);
+ sfree(ds->texty);
}
#ifdef COMBINED
dup_game,
free_game,
1, solve_game,
- TRUE, game_text_format,
+ TRUE, game_can_format_as_text_now, game_text_format,
new_ui,
free_ui,
encode_ui,
game_redraw,
game_anim_length,
game_flash_length,
+ game_status,
TRUE, FALSE, game_print_size, game_print,
FALSE /* wants_statusbar */,
FALSE, game_timing_state,
0, /* mouse_priorities */
};
+
+#ifdef STANDALONE_SOLVER
+
+/*
+ * Half-hearted standalone solver. It can't output the solution to
+ * anything but a square puzzle, and it can't log the deductions
+ * it makes either. But it can solve square puzzles, and more
+ * importantly it can use its solver to grade the difficulty of
+ * any puzzle you give it.
+ */
+
+#include <stdarg.h>
+
+int main(int argc, char **argv)
+{
+ game_params *p;
+ game_state *s;
+ char *id = NULL, *desc, *err;
+ int grade = FALSE;
+ int ret, diff;
+#if 0 /* verbose solver not supported here (yet) */
+ int really_verbose = FALSE;
+#endif
+
+ while (--argc > 0) {
+ char *p = *++argv;
+#if 0 /* verbose solver not supported here (yet) */
+ if (!strcmp(p, "-v")) {
+ really_verbose = TRUE;
+ } else
+#endif
+ if (!strcmp(p, "-g")) {
+ grade = TRUE;
+ } else if (*p == '-') {
+ fprintf(stderr, "%s: unrecognised option `%s'\n", argv[0], p);
+ return 1;
+ } else {
+ id = p;
+ }
+ }
+
+ if (!id) {
+ fprintf(stderr, "usage: %s [-g | -v] <game_id>\n", argv[0]);
+ return 1;
+ }
+
+ desc = strchr(id, ':');
+ if (!desc) {
+ fprintf(stderr, "%s: game id expects a colon in it\n", argv[0]);
+ return 1;
+ }
+ *desc++ = '\0';
+
+ p = default_params();
+ decode_params(p, id);
+ err = validate_desc(p, desc);
+ if (err) {
+ fprintf(stderr, "%s: %s\n", argv[0], err);
+ return 1;
+ }
+ s = new_game(NULL, p, desc);
+
+ /*
+ * When solving an Easy puzzle, we don't want to bother the
+ * user with Hard-level deductions. For this reason, we grade
+ * the puzzle internally before doing anything else.
+ */
+ ret = -1; /* placate optimiser */
+ for (diff = 0; diff < DIFF_MAX; diff++) {
+ solver_state *sstate_new;
+ solver_state *sstate = new_solver_state((game_state *)s, diff);
+
+ sstate_new = solve_game_rec(sstate);
+
+ if (sstate_new->solver_status == SOLVER_MISTAKE)
+ ret = 0;
+ else if (sstate_new->solver_status == SOLVER_SOLVED)
+ ret = 1;
+ else
+ ret = 2;
+
+ free_solver_state(sstate_new);
+ free_solver_state(sstate);
+
+ if (ret < 2)
+ break;
+ }
+
+ if (diff == DIFF_MAX) {
+ if (grade)
+ printf("Difficulty rating: harder than Hard, or ambiguous\n");
+ else
+ printf("Unable to find a unique solution\n");
+ } else {
+ if (grade) {
+ if (ret == 0)
+ printf("Difficulty rating: impossible (no solution exists)\n");
+ else if (ret == 1)
+ printf("Difficulty rating: %s\n", diffnames[diff]);
+ } else {
+ solver_state *sstate_new;
+ solver_state *sstate = new_solver_state((game_state *)s, diff);
+
+ /* If we supported a verbose solver, we'd set verbosity here */
+
+ sstate_new = solve_game_rec(sstate);
+
+ if (sstate_new->solver_status == SOLVER_MISTAKE)
+ printf("Puzzle is inconsistent\n");
+ else {
+ assert(sstate_new->solver_status == SOLVER_SOLVED);
+ if (s->grid_type == 0) {
+ fputs(game_text_format(sstate_new->state), stdout);
+ } else {
+ printf("Unable to output non-square grids\n");
+ }
+ }
+
+ free_solver_state(sstate_new);
+ free_solver_state(sstate);
+ }
+ }
+
+ return 0;
+}
+
+#endif
+
+/* vim: set shiftwidth=4 tabstop=8: */
~ian / sgt-puzzles.git / blobdiff