ref: 0cfaa8fbd77ea39a6752e5df66dc6559a52585e4
dir: /filling.c/
/*
* filling.c: An implementation of the Nikoli game fillomino.
* Copyright (C) 2007 Jonas Kölker. See LICENSE for the license.
*/
/* TODO:
*
* - use a typedef instead of int for numbers on the board
* + replace int with something else (signed short?)
* - the type should be signed (for -board[i] and -SENTINEL)
* - the type should be somewhat big: board[i] = i
* - Using shorts gives us 181x181 puzzles as upper bound.
*
* - in board generation, after having merged regions such that no
* more merges are necessary, try splitting (big) regions.
* + it seems that smaller regions make for better puzzles; see
* for instance the 7x7 puzzle in this file (grep for 7x7:).
*
* - symmetric hints (solo-style)
* + right now that means including _many_ hints, and the puzzles
* won't look any nicer. Not worth it (at the moment).
*
* - make the solver do recursion/backtracking.
* + This is for user-submitted puzzles, not for puzzle
* generation (on the other hand, never say never).
*
* - prove that only w=h=2 needs a special case
*
* - solo-like pencil marks?
*
* - a user says that the difficulty is unevenly distributed.
* + partition into levels? Will they be non-crap?
*
* - Allow square contents > 9?
* + I could use letters for digits (solo does this), but
* letters don't have numeric significance (normal people hate
* base36), which is relevant here (much more than in solo).
* + [click, 1, 0, enter] => [10 in clicked square]?
* + How much information is needed to solve? Does one need to
* know the algorithm by which the largest number is set?
*
* - eliminate puzzle instances with done chunks (1's in particular)?
* + that's what the qsort call is all about.
* + the 1's don't bother me that much.
* + but this takes a LONG time (not always possible)?
* - this may be affected by solver (lack of) quality.
* - weed them out by construction instead of post-cons check
* + but that interleaves make_board and new_game_desc: you
* have to alternate between changing the board and
* changing the hint set (instead of just creating the
* board once, then changing the hint set once -> done).
*
* - use binary search when discovering the minimal sovable point
* + profile to show a need (but when the solver gets slower...)
* + 7x9 @ .011s, 9x13 @ .075s, 17x13 @ .661s (all avg with n=100)
* + but the hints are independent, not linear, so... what?
*/
#include <assert.h>
#include <ctype.h>
#ifdef NO_TGMATH_H
# include <math.h>
#else
# include <tgmath.h>
#endif
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "puzzles.h"
static bool verbose;
static void printv(const char *fmt, ...) {
#ifndef PALM
if (verbose) {
va_list va;
va_start(va, fmt);
vprintf(fmt, va);
va_end(va);
}
#endif
}
/*****************************************************************************
* GAME CONFIGURATION AND PARAMETERS *
*****************************************************************************/
struct game_params {
int w, h;
};
struct shared_state {
struct game_params params;
int *clues;
int refcnt;
};
struct game_state {
int *board;
struct shared_state *shared;
bool completed, cheated;
};
static const struct game_params filling_defaults[3] = {
{9, 7}, {13, 9}, {17, 13}
};
static game_params *default_params(void)
{
game_params *ret = snew(game_params);
*ret = filling_defaults[1]; /* struct copy */
return ret;
}
static bool game_fetch_preset(int i, char **name, game_params **params)
{
char buf[64];
if (i < 0 || i >= lenof(filling_defaults)) return false;
*params = snew(game_params);
**params = filling_defaults[i]; /* struct copy */
sprintf(buf, "%dx%d", filling_defaults[i].w, filling_defaults[i].h);
*name = dupstr(buf);
return true;
}
static void free_params(game_params *params)
{
sfree(params);
}
static game_params *dup_params(const game_params *params)
{
game_params *ret = snew(game_params);
*ret = *params; /* struct copy */
return ret;
}
static void decode_params(game_params *ret, char const *string)
{
ret->w = ret->h = atoi(string);
while (*string && isdigit((unsigned char) *string)) ++string;
if (*string == 'x') ret->h = atoi(++string);
}
static char *encode_params(const game_params *params, bool full)
{
char buf[64];
sprintf(buf, "%dx%d", params->w, params->h);
return dupstr(buf);
}
static config_item *game_configure(const game_params *params)
{
config_item *ret;
char buf[64];
ret = snewn(3, config_item);
ret[0].name = "Width";
ret[0].type = C_STRING;
sprintf(buf, "%d", params->w);
ret[0].u.string.sval = dupstr(buf);
ret[1].name = "Height";
ret[1].type = C_STRING;
sprintf(buf, "%d", params->h);
ret[1].u.string.sval = dupstr(buf);
ret[2].name = NULL;
ret[2].type = C_END;
return ret;
}
static game_params *custom_params(const config_item *cfg)
{
game_params *ret = snew(game_params);
ret->w = atoi(cfg[0].u.string.sval);
ret->h = atoi(cfg[1].u.string.sval);
return ret;
}
static const char *validate_params(const game_params *params, bool full)
{
if (params->w < 1) return "Width must be at least one";
if (params->h < 1) return "Height must be at least one";
if (params->w > INT_MAX / params->h)
return "Width times height must not be unreasonably large";
return NULL;
}
/*****************************************************************************
* STRINGIFICATION OF GAME STATE *
*****************************************************************************/
#define EMPTY 0
/* Example of plaintext rendering:
* +---+---+---+---+---+---+---+
* | 6 | | | 2 | | | 2 |
* +---+---+---+---+---+---+---+
* | | 3 | | 6 | | 3 | |
* +---+---+---+---+---+---+---+
* | 3 | | | | | | 1 |
* +---+---+---+---+---+---+---+
* | | 2 | 3 | | 4 | 2 | |
* +---+---+---+---+---+---+---+
* | 2 | | | | | | 3 |
* +---+---+---+---+---+---+---+
* | | 5 | | 1 | | 4 | |
* +---+---+---+---+---+---+---+
* | 4 | | | 3 | | | 3 |
* +---+---+---+---+---+---+---+
*
* This puzzle instance is taken from the nikoli website
* Encoded (unsolved and solved), the strings are these:
* 7x7:6002002030603030000010230420200000305010404003003
* 7x7:6662232336663232331311235422255544325413434443313
*/
static char *board_to_string(int *board, int w, int h) {
const int sz = w * h;
const int chw = (4*w + 2); /* +2 for trailing '+' and '\n' */
const int chh = (2*h + 1); /* +1: n fence segments, n+1 posts */
const int chlen = chw * chh;
char *repr = snewn(chlen + 1, char);
int i;
assert(board);
/* build the first line ("^(\+---){n}\+$") */
for (i = 0; i < w; ++i) {
repr[4*i + 0] = '+';
repr[4*i + 1] = '-';
repr[4*i + 2] = '-';
repr[4*i + 3] = '-';
}
repr[4*i + 0] = '+';
repr[4*i + 1] = '\n';
/* ... and copy it onto the odd-numbered lines */
for (i = 0; i < h; ++i) memcpy(repr + (2*i + 2) * chw, repr, chw);
/* build the second line ("^(\|\t){n}\|$") */
for (i = 0; i < w; ++i) {
repr[chw + 4*i + 0] = '|';
repr[chw + 4*i + 1] = ' ';
repr[chw + 4*i + 2] = ' ';
repr[chw + 4*i + 3] = ' ';
}
repr[chw + 4*i + 0] = '|';
repr[chw + 4*i + 1] = '\n';
/* ... and copy it onto the even-numbered lines */
for (i = 1; i < h; ++i) memcpy(repr + (2*i + 1) * chw, repr + chw, chw);
/* fill in the numbers */
for (i = 0; i < sz; ++i) {
const int x = i % w;
const int y = i / w;
if (board[i] == EMPTY) continue;
repr[chw*(2*y + 1) + (4*x + 2)] = board[i] + '0';
}
repr[chlen] = '\0';
return repr;
}
static bool game_can_format_as_text_now(const game_params *params)
{
return true;
}
static char *game_text_format(const game_state *state)
{
const int w = state->shared->params.w;
const int h = state->shared->params.h;
return board_to_string(state->board, w, h);
}
/*****************************************************************************
* GAME GENERATION AND SOLVER *
*****************************************************************************/
static const int dx[4] = {-1, 1, 0, 0};
static const int dy[4] = {0, 0, -1, 1};
struct solver_state
{
DSF *dsf;
int *board;
int *connected;
int nempty;
/* Used internally by learn_bitmap_deductions; kept here to avoid
* mallocing/freeing them every time that function is called. */
int *bm, *bmminsize;
DSF *bmdsf;
};
static void print_board(int *board, int w, int h) {
if (verbose) {
char *repr = board_to_string(board, w, h);
printv("%s\n", repr);
free(repr);
}
}
static game_state *new_game(midend *, const game_params *, const char *);
static void free_game(game_state *);
#define SENTINEL (sz+1)
static bool mark_region(int *board, int w, int h, int i, int n, int m) {
int j;
board[i] = -1;
for (j = 0; j < 4; ++j) {
const int x = (i % w) + dx[j], y = (i / w) + dy[j], ii = w*y + x;
if (x < 0 || x >= w || y < 0 || y >= h) continue;
if (board[ii] == m) return false;
if (board[ii] != n) continue;
if (!mark_region(board, w, h, ii, n, m)) return false;
}
return true;
}
static int region_size(int *board, int w, int h, int i) {
const int sz = w * h;
int j, size, copy;
if (board[i] == 0) return 0;
copy = board[i];
mark_region(board, w, h, i, board[i], SENTINEL);
for (size = j = 0; j < sz; ++j) {
if (board[j] != -1) continue;
++size;
board[j] = copy;
}
return size;
}
static void merge_ones(int *board, int w, int h)
{
const int sz = w * h;
const int maxsize = min(max(max(w, h), 3), 9);
int i, j, k;
bool change;
do {
change = false;
for (i = 0; i < sz; ++i) {
if (board[i] != 1) continue;
for (j = 0; j < 4; ++j, board[i] = 1) {
const int x = (i % w) + dx[j], y = (i / w) + dy[j];
int oldsize, newsize, ii = w*y + x;
bool ok;
if (x < 0 || x >= w || y < 0 || y >= h) continue;
if (board[ii] == maxsize) continue;
oldsize = board[ii];
board[i] = oldsize;
newsize = region_size(board, w, h, i);
if (newsize > maxsize) continue;
ok = mark_region(board, w, h, i, oldsize, newsize);
for (k = 0; k < sz; ++k)
if (board[k] == -1)
board[k] = ok ? newsize : oldsize;
if (ok) break;
}
if (j < 4) change = true;
}
} while (change);
}
/* generate a random valid board; uses validate_board. */
static void make_board(int *board, int w, int h, random_state *rs) {
const int sz = w * h;
/* w=h=2 is a special case which requires a number > max(w, h) */
/* TODO prove that this is the case ONLY for w=h=2. */
const int maxsize = min(max(max(w, h), 3), 9);
/* Note that if 1 in {w, h} then it's impossible to have a region
* of size > w*h, so the special case only affects w=h=2. */
int i;
DSF *dsf;
bool change;
assert(w >= 1);
assert(h >= 1);
assert(board);
/* I abuse the board variable: when generating the puzzle, it
* contains a shuffled list of numbers {0, ..., sz-1}. */
for (i = 0; i < sz; ++i) board[i] = i;
dsf = dsf_new(sz);
retry:
dsf_reinit(dsf);
shuffle(board, sz, sizeof (int), rs);
do {
change = false; /* as long as the board potentially has errors */
for (i = 0; i < sz; ++i) {
const int square = dsf_canonify(dsf, board[i]);
const int size = dsf_size(dsf, square);
int merge = SENTINEL, min = maxsize - size + 1;
bool error = false;
int neighbour, neighbour_size, j;
int directions[4];
for (j = 0; j < 4; ++j)
directions[j] = j;
shuffle(directions, 4, sizeof(int), rs);
for (j = 0; j < 4; ++j) {
const int x = (board[i] % w) + dx[directions[j]];
const int y = (board[i] / w) + dy[directions[j]];
if (x < 0 || x >= w || y < 0 || y >= h) continue;
neighbour = dsf_canonify(dsf, w*y + x);
if (square == neighbour) continue;
neighbour_size = dsf_size(dsf, neighbour);
if (size == neighbour_size) error = true;
/* find the smallest neighbour to merge with, which
* wouldn't make the region too large. (This is
* guaranteed by the initial value of `min'.) */
if (neighbour_size < min && random_upto(rs, 10)) {
min = neighbour_size;
merge = neighbour;
}
}
/* if this square is not in error, leave it be */
if (!error) continue;
/* if it is, but we can't fix it, retry the whole board.
* Maybe we could fix it by merging the conflicting
* neighbouring region(s) into some of their neighbours,
* but just restarting works out fine. */
if (merge == SENTINEL) goto retry;
/* merge with the smallest neighbouring workable region. */
dsf_merge(dsf, square, merge);
change = true;
}
} while (change);
for (i = 0; i < sz; ++i) board[i] = dsf_size(dsf, i);
merge_ones(board, w, h);
dsf_free(dsf);
}
static void merge(DSF *dsf, int *connected, int a, int b) {
int c;
assert(dsf);
assert(connected);
a = dsf_canonify(dsf, a);
b = dsf_canonify(dsf, b);
if (a == b) return;
dsf_merge(dsf, a, b);
c = connected[a];
connected[a] = connected[b];
connected[b] = c;
}
static void *memdup(const void *ptr, size_t len, size_t esz) {
void *dup = smalloc(len * esz);
assert(ptr);
memcpy(dup, ptr, len * esz);
return dup;
}
static void expand(struct solver_state *s, int w, int h, int t, int f) {
int j;
assert(s);
assert(s->board[t] == EMPTY); /* expand to empty square */
assert(s->board[f] != EMPTY); /* expand from non-empty square */
printv(
"learn: expanding %d from (%d, %d) into (%d, %d)\n",
s->board[f], f % w, f / w, t % w, t / w);
s->board[t] = s->board[f];
for (j = 0; j < 4; ++j) {
const int x = (t % w) + dx[j];
const int y = (t / w) + dy[j];
const int idx = w*y + x;
if (x < 0 || x >= w || y < 0 || y >= h) continue;
if (s->board[idx] != s->board[t]) continue;
merge(s->dsf, s->connected, t, idx);
}
--s->nempty;
}
static void clear_count(int *board, int sz) {
int i;
for (i = 0; i < sz; ++i) {
if (board[i] >= 0) continue;
else if (board[i] == -SENTINEL) board[i] = EMPTY;
else board[i] = -board[i];
}
}
static void flood_count(int *board, int w, int h, int i, int n, int *c) {
const int sz = w * h;
int k;
if (board[i] == EMPTY) board[i] = -SENTINEL;
else if (board[i] == n) board[i] = -board[i];
else return;
if (--*c == 0) return;
for (k = 0; k < 4; ++k) {
const int x = (i % w) + dx[k];
const int y = (i / w) + dy[k];
const int idx = w*y + x;
if (x < 0 || x >= w || y < 0 || y >= h) continue;
flood_count(board, w, h, idx, n, c);
if (*c == 0) return;
}
}
static bool check_capacity(int *board, int w, int h, int i) {
int n = board[i];
flood_count(board, w, h, i, board[i], &n);
clear_count(board, w * h);
return n == 0;
}
static int expandsize(const int *board, DSF *dsf, int w, int h, int i, int n) {
int j;
int nhits = 0;
int hits[4];
int size = 1;
for (j = 0; j < 4; ++j) {
const int x = (i % w) + dx[j];
const int y = (i / w) + dy[j];
const int idx = w*y + x;
int root;
int m;
if (x < 0 || x >= w || y < 0 || y >= h) continue;
if (board[idx] != n) continue;
root = dsf_canonify(dsf, idx);
for (m = 0; m < nhits && root != hits[m]; ++m);
if (m < nhits) continue;
printv("\t (%d, %d) contrib %d to size\n", x, y, dsf_size(dsf, root));
size += dsf_size(dsf, root);
assert(dsf_size(dsf, root) >= 1);
hits[nhits++] = root;
}
return size;
}
/*
* +---+---+---+---+---+---+---+
* | 6 | | | 2 | | | 2 |
* +---+---+---+---+---+---+---+
* | | 3 | | 6 | | 3 | |
* +---+---+---+---+---+---+---+
* | 3 | | | | | | 1 |
* +---+---+---+---+---+---+---+
* | | 2 | 3 | | 4 | 2 | |
* +---+---+---+---+---+---+---+
* | 2 | | | | | | 3 |
* +---+---+---+---+---+---+---+
* | | 5 | | 1 | | 4 | |
* +---+---+---+---+---+---+---+
* | 4 | | | 3 | | | 3 |
* +---+---+---+---+---+---+---+
*/
/* Solving techniques:
*
* CONNECTED COMPONENT FORCED EXPANSION (too big):
* When a CC can only be expanded in one direction, because all the
* other ones would make the CC too big.
* +---+---+---+---+---+
* | 2 | 2 | | 2 | _ |
* +---+---+---+---+---+
*
* CONNECTED COMPONENT FORCED EXPANSION (too small):
* When a CC must include a particular square, because otherwise there
* would not be enough room to complete it. This includes squares not
* adjacent to the CC through learn_critical_square.
* +---+---+
* | 2 | _ |
* +---+---+
*
* DROPPING IN A ONE:
* When an empty square has no neighbouring empty squares and only a 1
* will go into the square (or other CCs would be too big).
* +---+---+---+
* | 2 | 2 | _ |
* +---+---+---+
*
* TODO: generalise DROPPING IN A ONE: find the size of the CC of
* empty squares and a list of all adjacent numbers. See if only one
* number in {1, ..., size} u {all adjacent numbers} is possible.
* Probably this is only effective for a CC size < n for some n (4?)
*
* TODO: backtracking.
*/
static void filled_square(struct solver_state *s, int w, int h, int i) {
int j;
for (j = 0; j < 4; ++j) {
const int x = (i % w) + dx[j];
const int y = (i / w) + dy[j];
const int idx = w*y + x;
if (x < 0 || x >= w || y < 0 || y >= h) continue;
if (s->board[i] == s->board[idx])
merge(s->dsf, s->connected, i, idx);
}
}
static void init_solver_state(struct solver_state *s, int w, int h) {
const int sz = w * h;
int i;
assert(s);
s->nempty = 0;
for (i = 0; i < sz; ++i) s->connected[i] = i;
for (i = 0; i < sz; ++i)
if (s->board[i] == EMPTY) ++s->nempty;
else filled_square(s, w, h, i);
}
static bool learn_expand_or_one(struct solver_state *s, int w, int h) {
const int sz = w * h;
int i;
bool learn = false;
assert(s);
for (i = 0; i < sz; ++i) {
int j;
bool one = true;
if (s->board[i] != EMPTY) continue;
for (j = 0; j < 4; ++j) {
const int x = (i % w) + dx[j];
const int y = (i / w) + dy[j];
const int idx = w*y + x;
if (x < 0 || x >= w || y < 0 || y >= h) continue;
if (s->board[idx] == EMPTY) {
one = false;
continue;
}
if (one &&
(s->board[idx] == 1 ||
(s->board[idx] >= expandsize(s->board, s->dsf, w, h,
i, s->board[idx]))))
one = false;
if (dsf_size(s->dsf, idx) == s->board[idx]) continue;
assert(s->board[i] == EMPTY);
s->board[i] = -SENTINEL;
if (check_capacity(s->board, w, h, idx)) continue;
assert(s->board[i] == EMPTY);
printv("learn: expanding in one\n");
expand(s, w, h, i, idx);
learn = true;
break;
}
if (j == 4 && one) {
printv("learn: one at (%d, %d)\n", i % w, i / w);
assert(s->board[i] == EMPTY);
s->board[i] = 1;
assert(s->nempty);
--s->nempty;
learn = true;
}
}
return learn;
}
static bool learn_blocked_expansion(struct solver_state *s, int w, int h) {
const int sz = w * h;
int i;
bool learn = false;
assert(s);
/* for every connected component */
for (i = 0; i < sz; ++i) {
int exp = SENTINEL;
int j;
if (s->board[i] == EMPTY) continue;
j = dsf_canonify(s->dsf, i);
/* (but only for each connected component) */
if (i != j) continue;
/* (and not if it's already complete) */
if (dsf_size(s->dsf, j) == s->board[j]) continue;
/* for each square j _in_ the connected component */
do {
int k;
printv(" looking at (%d, %d)\n", j % w, j / w);
/* for each neighbouring square (idx) */
for (k = 0; k < 4; ++k) {
const int x = (j % w) + dx[k];
const int y = (j / w) + dy[k];
const int idx = w*y + x;
int size;
/* int l;
int nhits = 0;
int hits[4]; */
if (x < 0 || x >= w || y < 0 || y >= h) continue;
if (s->board[idx] != EMPTY) continue;
if (exp == idx) continue;
printv("\ttrying to expand onto (%d, %d)\n", x, y);
/* find out the would-be size of the new connected
* component if we actually expanded into idx */
/*
size = 1;
for (l = 0; l < 4; ++l) {
const int lx = x + dx[l];
const int ly = y + dy[l];
const int idxl = w*ly + lx;
int root;
int m;
if (lx < 0 || lx >= w || ly < 0 || ly >= h) continue;
if (board[idxl] != board[j]) continue;
root = dsf_canonify(dsf, idxl);
for (m = 0; m < nhits && root != hits[m]; ++m);
if (m != nhits) continue;
// printv("\t (%d, %d) contributed %d to size\n", lx, ly, dsf[root] >> 2);
size += dsf_size(dsf, root);
assert(dsf_size(dsf, root) >= 1);
hits[nhits++] = root;
}
*/
size = expandsize(s->board, s->dsf, w, h, idx, s->board[j]);
/* ... and see if that size is too big, or if we
* have other expansion candidates. Otherwise
* remember the (so far) only candidate. */
printv("\tthat would give a size of %d\n", size);
if (size > s->board[j]) continue;
/* printv("\tnow knowing %d expansions\n", nexpand + 1); */
if (exp != SENTINEL) goto next_i;
assert(exp != idx);
exp = idx;
}
j = s->connected[j]; /* next square in the same CC */
assert(s->board[i] == s->board[j]);
} while (j != i);
/* end: for each square j _in_ the connected component */
if (exp == SENTINEL) continue;
printv("learning to expand\n");
expand(s, w, h, exp, i);
learn = true;
next_i:
;
}
/* end: for each connected component */
return learn;
}
static bool learn_critical_square(struct solver_state *s, int w, int h) {
const int sz = w * h;
int i;
bool learn = false;
assert(s);
/* for each connected component */
for (i = 0; i < sz; ++i) {
int j, slack;
if (s->board[i] == EMPTY) continue;
if (i != dsf_canonify(s->dsf, i)) continue;
slack = s->board[i] - dsf_size(s->dsf, i);
if (slack == 0) continue;
assert(s->board[i] != 1);
/* for each empty square */
for (j = 0; j < sz; ++j) {
if (s->board[j] == EMPTY) {
/* if it's too far away from the CC, don't bother */
int k = i, jx = j % w, jy = j / w;
do {
int kx = k % w, ky = k / w;
if (abs(kx - jx) + abs(ky - jy) <= slack) break;
k = s->connected[k];
} while (i != k);
if (i == k) continue; /* not within range */
} else continue;
s->board[j] = -SENTINEL;
if (check_capacity(s->board, w, h, i)) continue;
/* if not expanding s->board[i] to s->board[j] implies
* that s->board[i] can't reach its full size, ... */
assert(s->nempty);
printv(
"learn: ds %d at (%d, %d) blocking (%d, %d)\n",
s->board[i], j % w, j / w, i % w, i / w);
--s->nempty;
s->board[j] = s->board[i];
filled_square(s, w, h, j);
learn = true;
}
}
return learn;
}
#if 0
static void print_bitmap(int *bitmap, int w, int h) {
if (verbose) {
int x, y;
for (y = 0; y < h; y++) {
for (x = 0; x < w; x++) {
printv(" %03x", bm[y*w+x]);
}
printv("\n");
}
}
}
#endif
static bool learn_bitmap_deductions(struct solver_state *s, int w, int h)
{
const int sz = w * h;
int *bm = s->bm;
DSF *dsf = s->bmdsf;
int *minsize = s->bmminsize;
int x, y, i, j, n;
bool learn = false;
/*
* This function does deductions based on building up a bitmap
* which indicates the possible numbers that can appear in each
* grid square. If we can rule out all but one possibility for a
* particular square, then we've found out the value of that
* square. In particular, this is one of the few forms of
* deduction capable of inferring the existence of a 'ghost
* region', i.e. a region which has none of its squares filled in
* at all.
*
* The reasoning goes like this. A currently unfilled square S can
* turn out to contain digit n in exactly two ways: either S is
* part of an n-region which also includes some currently known
* connected component of squares with n in, or S is part of an
* n-region separate from _all_ currently known connected
* components. If we can rule out both possibilities, then square
* S can't contain digit n at all.
*
* The former possibility: if there's a region of size n
* containing both S and some existing component C, then that
* means the distance from S to C must be small enough that C
* could be extended to include S without becoming too big. So we
* can do a breadth-first search out from all existing components
* with n in them, to identify all the squares which could be
* joined to any of them.
*
* The latter possibility: if there's a region of size n that
* doesn't contain _any_ existing component, then it also can't
* contain any square adjacent to an existing component either. So
* we can identify all the EMPTY squares not adjacent to any
* existing square with n in, and group them into connected
* components; then any component of size less than n is ruled
* out, because there wouldn't be room to create a completely new
* n-region in it.
*
* In fact we process these possibilities in the other order.
* First we find all the squares not adjacent to an existing
* square with n in; then we winnow those by removing too-small
* connected components, to get the set of squares which could
* possibly be part of a brand new n-region; and finally we do the
* breadth-first search to add in the set of squares which could
* possibly be added to some existing n-region.
*/
/*
* Start by initialising our bitmap to 'all numbers possible in
* all squares'.
*/
for (y = 0; y < h; y++)
for (x = 0; x < w; x++)
bm[y*w+x] = (1 << 10) - (1 << 1); /* bits 1,2,...,9 now set */
#if 0
printv("initial bitmap:\n");
print_bitmap(bm, w, h);
#endif
/*
* Now completely zero out the bitmap for squares that are already
* filled in (we aren't interested in those anyway). Also, for any
* filled square, eliminate its number from all its neighbours
* (because, as discussed above, the neighbours couldn't be part
* of a _new_ region with that number in it, and that's the case
* we consider first).
*/
for (y = 0; y < h; y++) {
for (x = 0; x < w; x++) {
i = y*w+x;
n = s->board[i];
if (n != EMPTY) {
bm[i] = 0;
if (x > 0)
bm[i-1] &= ~(1 << n);
if (x+1 < w)
bm[i+1] &= ~(1 << n);
if (y > 0)
bm[i-w] &= ~(1 << n);
if (y+1 < h)
bm[i+w] &= ~(1 << n);
}
}
}
#if 0
printv("bitmap after filled squares:\n");
print_bitmap(bm, w, h);
#endif
/*
* Now, for each n, we separately find the connected components of
* squares for which n is still a possibility. Then discard any
* component of size < n, because that component is too small to
* have a completely new n-region in it.
*/
for (n = 1; n <= 9; n++) {
dsf_reinit(dsf);
/* Build the dsf */
for (y = 0; y < h; y++)
for (x = 0; x+1 < w; x++)
if (bm[y*w+x] & bm[y*w+(x+1)] & (1 << n))
dsf_merge(dsf, y*w+x, y*w+(x+1));
for (y = 0; y+1 < h; y++)
for (x = 0; x < w; x++)
if (bm[y*w+x] & bm[(y+1)*w+x] & (1 << n))
dsf_merge(dsf, y*w+x, (y+1)*w+x);
/* Query the dsf */
for (i = 0; i < sz; i++)
if ((bm[i] & (1 << n)) && dsf_size(dsf, i) < n)
bm[i] &= ~(1 << n);
}
#if 0
printv("bitmap after winnowing small components:\n");
print_bitmap(bm, w, h);
#endif
/*
* Now our bitmap includes every square which could be part of a
* completely new region, of any size. Extend it to include
* squares which could be part of an existing region.
*/
for (n = 1; n <= 9; n++) {
/*
* We're going to do a breadth-first search starting from
* existing connected components with cell value n, to find
* all cells they might possibly extend into.
*
* The quantity we compute, for each square, is 'minimum size
* that any existing CC would have to have if extended to
* include this square'. So squares already _in_ an existing
* CC are initialised to the size of that CC; then we search
* outwards using the rule that if a square's score is j, then
* its neighbours can't score more than j+1.
*
* Scores are capped at n+1, because if a square scores more
* than n then that's enough to know it can't possibly be
* reached by extending an existing region - we don't need to
* know exactly _how far_ out of reach it is.
*/
for (i = 0; i < sz; i++) {
if (s->board[i] == n) {
/* Square is part of an existing CC. */
minsize[i] = dsf_size(s->dsf, i);
} else {
/* Otherwise, initialise to the maximum score n+1;
* we'll reduce this later if we find a neighbouring
* square with a lower score. */
minsize[i] = n+1;
}
}
for (j = 1; j < n; j++) {
/*
* Find neighbours of cells scoring j, and set their score
* to at most j+1.
*
* Doing the BFS this way means we need n passes over the
* grid, which isn't entirely optimal but it seems to be
* fast enough for the moment. This could probably be
* improved by keeping a linked-list queue of cells in
* some way, but I think you'd have to be a bit careful to
* insert things into the right place in the queue; this
* way is easier not to get wrong.
*/
for (y = 0; y < h; y++) {
for (x = 0; x < w; x++) {
i = y*w+x;
if (minsize[i] == j) {
if (x > 0 && minsize[i-1] > j+1)
minsize[i-1] = j+1;
if (x+1 < w && minsize[i+1] > j+1)
minsize[i+1] = j+1;
if (y > 0 && minsize[i-w] > j+1)
minsize[i-w] = j+1;
if (y+1 < h && minsize[i+w] > j+1)
minsize[i+w] = j+1;
}
}
}
}
/*
* Now, every cell scoring at most n should have its 1<<n bit
* in the bitmap reinstated, because we've found that it's
* potentially reachable by extending an existing CC.
*/
for (i = 0; i < sz; i++)
if (minsize[i] <= n)
bm[i] |= 1<<n;
}
#if 0
printv("bitmap after bfs:\n");
print_bitmap(bm, w, h);
#endif
/*
* Now our bitmap is complete. Look for entries with only one bit
* set; those are squares with only one possible number, in which
* case we can fill that number in.
*/
for (i = 0; i < sz; i++) {
if (bm[i] && !(bm[i] & (bm[i]-1))) { /* is bm[i] a power of two? */
int val = bm[i];
/* Integer log2, by simple binary search. */
n = 0;
if (val >> 8) { val >>= 8; n += 8; }
if (val >> 4) { val >>= 4; n += 4; }
if (val >> 2) { val >>= 2; n += 2; }
if (val >> 1) { val >>= 1; n += 1; }
/* Double-check that we ended up with a sensible
* answer. */
assert(1 <= n);
assert(n <= 9);
assert(bm[i] == (1 << n));
if (s->board[i] == EMPTY) {
printv("learn: %d is only possibility at (%d, %d)\n",
n, i % w, i / w);
s->board[i] = n;
filled_square(s, w, h, i);
assert(s->nempty);
--s->nempty;
learn = true;
}
}
}
return learn;
}
static bool solver(const int *orig, int w, int h, char **solution) {
const int sz = w * h;
struct solver_state ss;
ss.board = memdup(orig, sz, sizeof (int));
ss.dsf = dsf_new(sz); /* eqv classes: connected components */
ss.connected = snewn(sz, int); /* connected[n] := n.next; */
/* cyclic disjoint singly linked lists, same partitioning as dsf.
* The lists lets you iterate over a partition given any member */
ss.bm = snewn(sz, int);
ss.bmdsf = dsf_new(sz);
ss.bmminsize = snewn(sz, int);
printv("trying to solve this:\n");
print_board(ss.board, w, h);
init_solver_state(&ss, w, h);
do {
if (learn_blocked_expansion(&ss, w, h)) continue;
if (learn_expand_or_one(&ss, w, h)) continue;
if (learn_critical_square(&ss, w, h)) continue;
if (learn_bitmap_deductions(&ss, w, h)) continue;
break;
} while (ss.nempty);
printv("best guess:\n");
print_board(ss.board, w, h);
if (solution) {
int i;
*solution = snewn(sz + 2, char);
**solution = 's';
for (i = 0; i < sz; ++i) (*solution)[i + 1] = ss.board[i] + '0';
(*solution)[sz + 1] = '\0';
}
dsf_free(ss.dsf);
sfree(ss.board);
sfree(ss.connected);
sfree(ss.bm);
dsf_free(ss.bmdsf);
sfree(ss.bmminsize);
return !ss.nempty;
}
static DSF *make_dsf(DSF *dsf, int *board, const int w, const int h) {
const int sz = w * h;
int i;
if (!dsf)
dsf = dsf_new_min(w * h);
else
dsf_reinit(dsf);
for (i = 0; i < sz; ++i) {
int j;
for (j = 0; j < 4; ++j) {
const int x = (i % w) + dx[j];
const int y = (i / w) + dy[j];
const int k = w*y + x;
if (x < 0 || x >= w || y < 0 || y >= h) continue;
if (board[i] == board[k]) dsf_merge(dsf, i, k);
}
}
return dsf;
}
static void minimize_clue_set(int *board, int w, int h, random_state *rs)
{
const int sz = w * h;
int *shuf = snewn(sz, int), i;
DSF *dsf;
int *next;
for (i = 0; i < sz; ++i) shuf[i] = i;
shuffle(shuf, sz, sizeof (int), rs);
/*
* First, try to eliminate an entire region at a time if possible,
* because inferring the existence of a completely unclued region
* is a particularly good aspect of this puzzle type and we want
* to encourage it to happen.
*
* Begin by identifying the regions as linked lists of cells using
* the 'next' array.
*/
dsf = make_dsf(NULL, board, w, h);
next = snewn(sz, int);
for (i = 0; i < sz; ++i) {
int j = dsf_minimal(dsf, i);
if (i == j) {
/* First cell of a region; set next[i] = -1 to indicate
* end-of-list. */
next[i] = -1;
} else {
/* Add this cell to a region which already has a
* linked-list head, by pointing the minimal element j
* at this one, and pointing this one in turn at wherever
* j previously pointed. (This should end up with the
* elements linked in the order 1,n,n-1,n-2,...,2, which
* is a bit weird-looking, but any order is fine.)
*/
assert(j < i);
next[i] = next[j];
next[j] = i;
}
}
/*
* Now loop over the grid cells in our shuffled order, and each
* time we encounter a region for the first time, try to remove it
* all. Then we set next[canonical index] to -2 rather than -1, to
* mark it as already tried.
*
* Doing this in a loop over _cells_, rather than extracting and
* shuffling a list of _regions_, is intended to skew the
* probabilities towards trying to remove larger regions first
* (but without anything as crudely predictable as enforcing that
* we _always_ process regions in descending size order). Region
* removals might well be mutually exclusive, and larger ghost
* regions are more interesting, so we want to bias towards them
* if we can.
*/
for (i = 0; i < sz; ++i) {
int j = dsf_minimal(dsf, shuf[i]);
if (next[j] != -2) {
int tmp = board[j];
int k;
/* Blank out the whole thing. */
for (k = j; k >= 0; k = next[k])
board[k] = EMPTY;
if (!solver(board, w, h, NULL)) {
/* Wasn't still solvable; reinstate it all */
for (k = j; k >= 0; k = next[k])
board[k] = tmp;
}
/* Either way, don't try this region again. */
next[j] = -2;
}
}
sfree(next);
dsf_free(dsf);
/*
* Now go through individual cells, in the same shuffled order,
* and try to remove each one by itself.
*/
for (i = 0; i < sz; ++i) {
int tmp = board[shuf[i]];
board[shuf[i]] = EMPTY;
if (!solver(board, w, h, NULL)) board[shuf[i]] = tmp;
}
sfree(shuf);
}
static int encode_run(char *buffer, int run)
{
int i = 0;
for (; run > 26; run -= 26)
buffer[i++] = 'z';
if (run)
buffer[i++] = 'a' - 1 + run;
return i;
}
static char *new_game_desc(const game_params *params, random_state *rs,
char **aux, bool interactive)
{
const int w = params->w, h = params->h, sz = w * h;
int *board = snewn(sz, int), i, j, run;
char *description = snewn(sz + 1, char);
make_board(board, w, h, rs);
minimize_clue_set(board, w, h, rs);
for (run = j = i = 0; i < sz; ++i) {
assert(board[i] >= 0);
assert(board[i] < 10);
if (board[i] == 0) {
++run;
} else {
j += encode_run(description + j, run);
run = 0;
description[j++] = board[i] + '0';
}
}
j += encode_run(description + j, run);
description[j++] = '\0';
sfree(board);
return sresize(description, j, char);
}
static const char *validate_desc(const game_params *params, const char *desc)
{
const int sz = params->w * params->h;
const char m = '0' + max(max(params->w, params->h), 3);
int area;
for (area = 0; *desc; ++desc) {
if (*desc >= 'a' && *desc <= 'z') area += *desc - 'a' + 1;
else if (*desc >= '0' && *desc <= m) ++area;
else {
static char s[] = "Invalid character '%""' in game description";
int n = sprintf(s, "Invalid character '%1c' in game description",
*desc);
assert(n + 1 <= lenof(s)); /* +1 for the terminating NUL */
return s;
}
if (area > sz) return "Too much data to fit in grid";
}
return (area < sz) ? "Not enough data to fill grid" : NULL;
}
static key_label *game_request_keys(const game_params *params, int *nkeys)
{
int i;
key_label *keys = snewn(11, key_label);
*nkeys = 11;
for(i = 0; i < 10; ++i)
{
keys[i].button = '0' + i;
keys[i].label = NULL;
}
keys[10].button = '\b';
keys[10].label = NULL;
return keys;
}
static game_state *new_game(midend *me, const game_params *params,
const char *desc)
{
game_state *state = snew(game_state);
int sz = params->w * params->h;
int i;
state->cheated = false;
state->completed = false;
state->shared = snew(struct shared_state);
state->shared->refcnt = 1;
state->shared->params = *params; /* struct copy */
state->shared->clues = snewn(sz, int);
for (i = 0; *desc; ++desc) {
if (*desc >= 'a' && *desc <= 'z') {
int j = *desc - 'a' + 1;
assert(i + j <= sz);
for (; j; --j) state->shared->clues[i++] = 0;
} else state->shared->clues[i++] = *desc - '0';
}
state->board = memdup(state->shared->clues, sz, sizeof (int));
return state;
}
static game_state *dup_game(const game_state *state)
{
const int sz = state->shared->params.w * state->shared->params.h;
game_state *ret = snew(game_state);
ret->board = memdup(state->board, sz, sizeof (int));
ret->shared = state->shared;
ret->cheated = state->cheated;
ret->completed = state->completed;
++ret->shared->refcnt;
return ret;
}
static void free_game(game_state *state)
{
assert(state);
sfree(state->board);
if (--state->shared->refcnt == 0) {
sfree(state->shared->clues);
sfree(state->shared);
}
sfree(state);
}
static char *solve_game(const game_state *state, const game_state *currstate,
const char *aux, const char **error)
{
if (aux == NULL) {
const int w = state->shared->params.w;
const int h = state->shared->params.h;
char *new_aux;
if (!solver(state->board, w, h, &new_aux))
*error = "Sorry, I couldn't find a solution";
return new_aux;
}
return dupstr(aux);
}
/*****************************************************************************
* USER INTERFACE STATE AND ACTION *
*****************************************************************************/
struct game_ui {
bool *sel; /* w*h highlighted squares, or NULL */
int cur_x, cur_y;
bool cur_visible, keydragging;
};
static game_ui *new_ui(const game_state *state)
{
game_ui *ui = snew(game_ui);
ui->sel = NULL;
ui->cur_x = ui->cur_y = 0;
ui->cur_visible = getenv_bool("PUZZLES_SHOW_CURSOR", false);
ui->keydragging = false;
return ui;
}
static void free_ui(game_ui *ui)
{
if (ui->sel)
sfree(ui->sel);
sfree(ui);
}
static void game_changed_state(game_ui *ui, const game_state *oldstate,
const game_state *newstate)
{
/* Clear any selection */
if (ui->sel) {
sfree(ui->sel);
ui->sel = NULL;
}
ui->keydragging = false;
}
static const char *current_key_label(const game_ui *ui,
const game_state *state, int button)
{
const int w = state->shared->params.w;
if (IS_CURSOR_SELECT(button) && ui->cur_visible) {
if (button == CURSOR_SELECT) {
if (ui->keydragging) return "Stop";
return "Multiselect";
}
if (button == CURSOR_SELECT2 &&
!state->shared->clues[w*ui->cur_y + ui->cur_x])
return (ui->sel[w*ui->cur_y + ui->cur_x]) ? "Deselect" : "Select";
}
return "";
}
#define PREFERRED_TILE_SIZE 32
#define TILE_SIZE (ds->tilesize)
#define BORDER (TILE_SIZE / 2)
#define BORDER_WIDTH (max(TILE_SIZE / 32, 1))
struct game_drawstate {
struct game_params params;
int tilesize;
bool started;
int *v, *flags;
DSF *dsf_scratch;
int *border_scratch;
};
static char *interpret_move(const game_state *state, game_ui *ui,
const game_drawstate *ds,
int x, int y, int button)
{
const int w = state->shared->params.w;
const int h = state->shared->params.h;
const int tx = (x + TILE_SIZE - BORDER) / TILE_SIZE - 1;
const int ty = (y + TILE_SIZE - BORDER) / TILE_SIZE - 1;
char *move = NULL;
int i;
assert(ui);
assert(ds);
button &= ~MOD_MASK;
if (button == LEFT_BUTTON || button == LEFT_DRAG) {
/* A left-click anywhere will clear the current selection. */
if (button == LEFT_BUTTON) {
if (ui->sel) {
sfree(ui->sel);
ui->sel = NULL;
}
}
if (tx >= 0 && tx < w && ty >= 0 && ty < h) {
if (!ui->sel) {
ui->sel = snewn(w*h, bool);
memset(ui->sel, 0, w*h*sizeof(bool));
}
if (!state->shared->clues[w*ty+tx])
ui->sel[w*ty+tx] = true;
}
ui->cur_visible = false;
return MOVE_UI_UPDATE;
}
if (IS_CURSOR_MOVE(button)) {
ui->cur_visible = true;
move_cursor(button, &ui->cur_x, &ui->cur_y, w, h, false, NULL);
if (ui->keydragging) goto select_square;
return MOVE_UI_UPDATE;
}
if (button == CURSOR_SELECT) {
if (!ui->cur_visible) {
ui->cur_visible = true;
return MOVE_UI_UPDATE;
}
ui->keydragging = !ui->keydragging;
if (!ui->keydragging) return MOVE_UI_UPDATE;
select_square:
if (!ui->sel) {
ui->sel = snewn(w*h, bool);
memset(ui->sel, 0, w*h*sizeof(bool));
}
if (!state->shared->clues[w*ui->cur_y + ui->cur_x])
ui->sel[w*ui->cur_y + ui->cur_x] = true;
return MOVE_UI_UPDATE;
}
if (button == CURSOR_SELECT2) {
if (!ui->cur_visible) {
ui->cur_visible = true;
return MOVE_UI_UPDATE;
}
if (!ui->sel) {
ui->sel = snewn(w*h, bool);
memset(ui->sel, 0, w*h*sizeof(bool));
}
ui->keydragging = false;
if (!state->shared->clues[w*ui->cur_y + ui->cur_x])
ui->sel[w*ui->cur_y + ui->cur_x] ^= 1;
for (i = 0; i < w*h && !ui->sel[i]; i++);
if (i == w*h) {
sfree(ui->sel);
ui->sel = NULL;
}
return MOVE_UI_UPDATE;
}
if (button == '\b' || button == 27) {
sfree(ui->sel);
ui->sel = NULL;
ui->keydragging = false;
return MOVE_UI_UPDATE;
}
if (button < '0' || button > '9') return MOVE_UNUSED;
button -= '0';
if (button > (w == 2 && h == 2 ? 3 : max(w, h))) return MOVE_UNUSED;
ui->keydragging = false;
for (i = 0; i < w*h; i++) {
char buf[32];
if ((ui->sel && ui->sel[i]) ||
(!ui->sel && ui->cur_visible && (w*ui->cur_y+ui->cur_x) == i)) {
if (state->shared->clues[i] != 0) continue; /* in case cursor is on clue */
if (state->board[i] != button) {
sprintf(buf, "%s%d", move ? "," : "", i);
if (move) {
move = srealloc(move, strlen(move)+strlen(buf)+1);
strcat(move, buf);
} else {
move = smalloc(strlen(buf)+1);
strcpy(move, buf);
}
}
}
}
if (move) {
char buf[32];
sprintf(buf, "_%d", button);
move = srealloc(move, strlen(move)+strlen(buf)+1);
strcat(move, buf);
}
if (!ui->sel) return move ? move : MOVE_NO_EFFECT;
sfree(ui->sel);
ui->sel = NULL;
/* Need to update UI at least, as we cleared the selection */
return move ? move : MOVE_UI_UPDATE;
}
static game_state *execute_move(const game_state *state, const char *move)
{
game_state *new_state = NULL;
const int sz = state->shared->params.w * state->shared->params.h;
if (*move == 's') {
int i = 0;
if (strlen(move) != sz + 1) return NULL;
new_state = dup_game(state);
for (++move; i < sz; ++i) new_state->board[i] = move[i] - '0';
new_state->cheated = true;
} else {
int value;
char *endptr, *delim = strchr(move, '_');
if (!delim) goto err;
value = strtol(delim+1, &endptr, 0);
if (*endptr || endptr == delim+1) goto err;
if (value < 0 || value > 9) goto err;
new_state = dup_game(state);
while (*move) {
const int i = strtol(move, &endptr, 0);
if (endptr == move) goto err;
if (i < 0 || i >= sz) goto err;
new_state->board[i] = value;
if (*endptr == '_') break;
if (*endptr != ',') goto err;
move = endptr + 1;
}
}
/*
* Check for completion.
*/
if (!new_state->completed) {
const int w = new_state->shared->params.w;
const int h = new_state->shared->params.h;
const int sz = w * h;
DSF *dsf = make_dsf(NULL, new_state->board, w, h);
int i;
for (i = 0; i < sz && new_state->board[i] == dsf_size(dsf, i); ++i);
dsf_free(dsf);
if (i == sz)
new_state->completed = true;
}
return new_state;
err:
if (new_state) free_game(new_state);
return NULL;
}
/* ----------------------------------------------------------------------
* Drawing routines.
*/
#define FLASH_TIME 0.4F
#define COL_CLUE COL_GRID
enum {
COL_BACKGROUND,
COL_GRID,
COL_HIGHLIGHT,
COL_CORRECT,
COL_ERROR,
COL_USER,
COL_CURSOR,
NCOLOURS
};
static void game_compute_size(const game_params *params, int tilesize,
const game_ui *ui, int *x, int *y)
{
*x = (params->w + 1) * tilesize;
*y = (params->h + 1) * tilesize;
}
static void game_set_size(drawing *dr, game_drawstate *ds,
const game_params *params, int tilesize)
{
ds->tilesize = tilesize;
}
static float *game_colours(frontend *fe, int *ncolours)
{
float *ret = snewn(3 * NCOLOURS, float);
frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]);
ret[COL_GRID * 3 + 0] = 0.0F;
ret[COL_GRID * 3 + 1] = 0.0F;
ret[COL_GRID * 3 + 2] = 0.0F;
ret[COL_HIGHLIGHT * 3 + 0] = 0.7F * ret[COL_BACKGROUND * 3 + 0];
ret[COL_HIGHLIGHT * 3 + 1] = 0.7F * ret[COL_BACKGROUND * 3 + 1];
ret[COL_HIGHLIGHT * 3 + 2] = 0.7F * ret[COL_BACKGROUND * 3 + 2];
ret[COL_CORRECT * 3 + 0] = 0.9F * ret[COL_BACKGROUND * 3 + 0];
ret[COL_CORRECT * 3 + 1] = 0.9F * ret[COL_BACKGROUND * 3 + 1];
ret[COL_CORRECT * 3 + 2] = 0.9F * ret[COL_BACKGROUND * 3 + 2];
ret[COL_CURSOR * 3 + 0] = 0.5F * ret[COL_BACKGROUND * 3 + 0];
ret[COL_CURSOR * 3 + 1] = 0.5F * ret[COL_BACKGROUND * 3 + 1];
ret[COL_CURSOR * 3 + 2] = 0.5F * ret[COL_BACKGROUND * 3 + 2];
ret[COL_ERROR * 3 + 0] = 1.0F;
ret[COL_ERROR * 3 + 1] = 0.85F * ret[COL_BACKGROUND * 3 + 1];
ret[COL_ERROR * 3 + 2] = 0.85F * ret[COL_BACKGROUND * 3 + 2];
ret[COL_USER * 3 + 0] = 0.0F;
ret[COL_USER * 3 + 1] = 0.6F * ret[COL_BACKGROUND * 3 + 1];
ret[COL_USER * 3 + 2] = 0.0F;
*ncolours = NCOLOURS;
return ret;
}
static game_drawstate *game_new_drawstate(drawing *dr, const game_state *state)
{
struct game_drawstate *ds = snew(struct game_drawstate);
int i;
ds->tilesize = PREFERRED_TILE_SIZE;
ds->started = false;
ds->params = state->shared->params;
ds->v = snewn(ds->params.w * ds->params.h, int);
ds->flags = snewn(ds->params.w * ds->params.h, int);
for (i = 0; i < ds->params.w * ds->params.h; i++)
ds->v[i] = ds->flags[i] = -1;
ds->border_scratch = snewn(ds->params.w * ds->params.h, int);
ds->dsf_scratch = NULL;
return ds;
}
static void game_free_drawstate(drawing *dr, game_drawstate *ds)
{
sfree(ds->v);
sfree(ds->flags);
sfree(ds->border_scratch);
dsf_free(ds->dsf_scratch);
sfree(ds);
}
#define BORDER_U 0x001
#define BORDER_D 0x002
#define BORDER_L 0x004
#define BORDER_R 0x008
#define BORDER_UR 0x010
#define BORDER_DR 0x020
#define BORDER_UL 0x040
#define BORDER_DL 0x080
#define HIGH_BG 0x100
#define CORRECT_BG 0x200
#define ERROR_BG 0x400
#define USER_COL 0x800
#define CURSOR_SQ 0x1000
static void draw_square(drawing *dr, game_drawstate *ds, int x, int y,
int n, int flags)
{
assert(dr);
assert(ds);
/*
* Clip to the grid square.
*/
clip(dr, BORDER + x*TILE_SIZE, BORDER + y*TILE_SIZE,
TILE_SIZE, TILE_SIZE);
/*
* Clear the square.
*/
draw_rect(dr,
BORDER + x*TILE_SIZE,
BORDER + y*TILE_SIZE,
TILE_SIZE,
TILE_SIZE,
(flags & HIGH_BG ? COL_HIGHLIGHT :
flags & ERROR_BG ? COL_ERROR :
flags & CORRECT_BG ? COL_CORRECT : COL_BACKGROUND));
/*
* Draw the grid lines.
*/
draw_line(dr, BORDER + x*TILE_SIZE, BORDER + y*TILE_SIZE,
BORDER + (x+1)*TILE_SIZE, BORDER + y*TILE_SIZE, COL_GRID);
draw_line(dr, BORDER + x*TILE_SIZE, BORDER + y*TILE_SIZE,
BORDER + x*TILE_SIZE, BORDER + (y+1)*TILE_SIZE, COL_GRID);
/*
* Draw the number.
*/
if (n) {
char buf[2];
buf[0] = n + '0';
buf[1] = '\0';
draw_text(dr,
(x + 1) * TILE_SIZE,
(y + 1) * TILE_SIZE,
FONT_VARIABLE,
TILE_SIZE / 2,
ALIGN_VCENTRE | ALIGN_HCENTRE,
flags & USER_COL ? COL_USER : COL_CLUE,
buf);
}
/*
* Draw bold lines around the borders.
*/
if (flags & BORDER_L)
draw_rect(dr,
BORDER + x*TILE_SIZE + 1,
BORDER + y*TILE_SIZE + 1,
BORDER_WIDTH,
TILE_SIZE - 1,
COL_GRID);
if (flags & BORDER_U)
draw_rect(dr,
BORDER + x*TILE_SIZE + 1,
BORDER + y*TILE_SIZE + 1,
TILE_SIZE - 1,
BORDER_WIDTH,
COL_GRID);
if (flags & BORDER_R)
draw_rect(dr,
BORDER + (x+1)*TILE_SIZE - BORDER_WIDTH,
BORDER + y*TILE_SIZE + 1,
BORDER_WIDTH,
TILE_SIZE - 1,
COL_GRID);
if (flags & BORDER_D)
draw_rect(dr,
BORDER + x*TILE_SIZE + 1,
BORDER + (y+1)*TILE_SIZE - BORDER_WIDTH,
TILE_SIZE - 1,
BORDER_WIDTH,
COL_GRID);
if (flags & BORDER_UL)
draw_rect(dr,
BORDER + x*TILE_SIZE + 1,
BORDER + y*TILE_SIZE + 1,
BORDER_WIDTH,
BORDER_WIDTH,
COL_GRID);
if (flags & BORDER_UR)
draw_rect(dr,
BORDER + (x+1)*TILE_SIZE - BORDER_WIDTH,
BORDER + y*TILE_SIZE + 1,
BORDER_WIDTH,
BORDER_WIDTH,
COL_GRID);
if (flags & BORDER_DL)
draw_rect(dr,
BORDER + x*TILE_SIZE + 1,
BORDER + (y+1)*TILE_SIZE - BORDER_WIDTH,
BORDER_WIDTH,
BORDER_WIDTH,
COL_GRID);
if (flags & BORDER_DR)
draw_rect(dr,
BORDER + (x+1)*TILE_SIZE - BORDER_WIDTH,
BORDER + (y+1)*TILE_SIZE - BORDER_WIDTH,
BORDER_WIDTH,
BORDER_WIDTH,
COL_GRID);
if (flags & CURSOR_SQ) {
int coff = TILE_SIZE/8;
draw_rect_outline(dr,
BORDER + x*TILE_SIZE + coff,
BORDER + y*TILE_SIZE + coff,
TILE_SIZE - coff*2,
TILE_SIZE - coff*2,
COL_CURSOR);
}
unclip(dr);
draw_update(dr,
BORDER + x*TILE_SIZE,
BORDER + y*TILE_SIZE,
TILE_SIZE,
TILE_SIZE);
}
static void draw_grid(
drawing *dr, game_drawstate *ds, const game_state *state,
const game_ui *ui, bool flashy, bool borders, bool shading)
{
const int w = state->shared->params.w;
const int h = state->shared->params.h;
int x;
int y;
/*
* Build a dsf for the board in its current state, to use for
* highlights and hints.
*/
ds->dsf_scratch = make_dsf(ds->dsf_scratch, state->board, w, h);
/*
* Work out where we're putting borders between the cells.
*/
for (y = 0; y < w*h; y++)
ds->border_scratch[y] = 0;
for (y = 0; y < h; y++)
for (x = 0; x < w; x++) {
int dx, dy;
int v1, s1, v2, s2;
for (dx = 0; dx <= 1; dx++) {
bool border = false;
dy = 1 - dx;
if (x+dx >= w || y+dy >= h)
continue;
v1 = state->board[y*w+x];
v2 = state->board[(y+dy)*w+(x+dx)];
s1 = dsf_size(ds->dsf_scratch, y*w+x);
s2 = dsf_size(ds->dsf_scratch, (y+dy)*w+(x+dx));
/*
* We only ever draw a border between two cells if
* they don't have the same contents.
*/
if (v1 != v2) {
/*
* But in that situation, we don't always draw
* a border. We do if the two cells both
* contain actual numbers...
*/
if (v1 && v2)
border = true;
/*
* ... or if at least one of them is a
* completed or overfull omino.
*/
if (v1 && s1 >= v1)
border = true;
if (v2 && s2 >= v2)
border = true;
}
if (border)
ds->border_scratch[y*w+x] |= (dx ? 1 : 2);
}
}
/*
* Actually do the drawing.
*/
for (y = 0; y < h; ++y)
for (x = 0; x < w; ++x) {
/*
* Determine what we need to draw in this square.
*/
int i = y*w+x, v = state->board[i];
int flags = 0;
if (flashy || !shading) {
/* clear all background flags */
} else if (ui && ui->sel && ui->sel[i]) {
flags |= HIGH_BG;
} else if (v) {
int size = dsf_size(ds->dsf_scratch, i);
if (size == v)
flags |= CORRECT_BG;
else if (size > v)
flags |= ERROR_BG;
else {
int rt = dsf_canonify(ds->dsf_scratch, i), j;
for (j = 0; j < w*h; ++j) {
int k;
if (dsf_canonify(ds->dsf_scratch, j) != rt) continue;
for (k = 0; k < 4; ++k) {
const int xx = j % w + dx[k], yy = j / w + dy[k];
if (xx >= 0 && xx < w && yy >= 0 && yy < h &&
state->board[yy*w + xx] == EMPTY)
goto noflag;
}
}
flags |= ERROR_BG;
noflag:
;
}
}
if (ui && ui->cur_visible && x == ui->cur_x && y == ui->cur_y)
flags |= CURSOR_SQ;
/*
* Borders at the very edges of the grid are
* independent of the `borders' flag.
*/
if (x == 0)
flags |= BORDER_L;
if (y == 0)
flags |= BORDER_U;
if (x == w-1)
flags |= BORDER_R;
if (y == h-1)
flags |= BORDER_D;
if (borders) {
if (x == 0 || (ds->border_scratch[y*w+(x-1)] & 1))
flags |= BORDER_L;
if (y == 0 || (ds->border_scratch[(y-1)*w+x] & 2))
flags |= BORDER_U;
if (x == w-1 || (ds->border_scratch[y*w+x] & 1))
flags |= BORDER_R;
if (y == h-1 || (ds->border_scratch[y*w+x] & 2))
flags |= BORDER_D;
if (y > 0 && x > 0 && (ds->border_scratch[(y-1)*w+(x-1)]))
flags |= BORDER_UL;
if (y > 0 && x < w-1 &&
((ds->border_scratch[(y-1)*w+x] & 1) ||
(ds->border_scratch[(y-1)*w+(x+1)] & 2)))
flags |= BORDER_UR;
if (y < h-1 && x > 0 &&
((ds->border_scratch[y*w+(x-1)] & 2) ||
(ds->border_scratch[(y+1)*w+(x-1)] & 1)))
flags |= BORDER_DL;
if (y < h-1 && x < w-1 &&
((ds->border_scratch[y*w+(x+1)] & 2) ||
(ds->border_scratch[(y+1)*w+x] & 1)))
flags |= BORDER_DR;
}
if (!state->shared->clues[y*w+x])
flags |= USER_COL;
if (ds->v[y*w+x] != v || ds->flags[y*w+x] != flags) {
draw_square(dr, ds, x, y, v, flags);
ds->v[y*w+x] = v;
ds->flags[y*w+x] = flags;
}
}
}
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)
{
const int w = state->shared->params.w;
const int h = state->shared->params.h;
const bool flashy =
flashtime > 0 &&
(flashtime <= FLASH_TIME/3 || flashtime >= FLASH_TIME*2/3);
if (!ds->started) {
/*
* Black rectangle which is the main grid.
*/
draw_rect(dr, BORDER - BORDER_WIDTH, BORDER - BORDER_WIDTH,
w*TILE_SIZE + 2*BORDER_WIDTH + 1,
h*TILE_SIZE + 2*BORDER_WIDTH + 1,
COL_GRID);
draw_update(dr, 0, 0, w*TILE_SIZE + 2*BORDER, h*TILE_SIZE + 2*BORDER);
ds->started = true;
}
draw_grid(dr, ds, state, ui, flashy, true, true);
}
static float game_anim_length(const game_state *oldstate,
const game_state *newstate, int dir, game_ui *ui)
{
return 0.0F;
}
static float game_flash_length(const game_state *oldstate,
const game_state *newstate, int dir, game_ui *ui)
{
assert(oldstate);
assert(newstate);
assert(newstate->shared);
assert(oldstate->shared == newstate->shared);
if (!oldstate->completed && newstate->completed &&
!oldstate->cheated && !newstate->cheated)
return FLASH_TIME;
return 0.0F;
}
static void game_get_cursor_location(const game_ui *ui,
const game_drawstate *ds,
const game_state *state,
const game_params *params,
int *x, int *y, int *w, int *h)
{
if(ui->cur_visible)
{
*x = BORDER + ui->cur_x * TILE_SIZE;
*y = BORDER + ui->cur_y * TILE_SIZE;
*w = *h = TILE_SIZE;
}
}
static int game_status(const game_state *state)
{
return state->completed ? +1 : 0;
}
static void game_print_size(const game_params *params, const game_ui *ui,
float *x, float *y)
{
int pw, ph;
/*
* I'll use 6mm squares by default.
*/
game_compute_size(params, 600, ui, &pw, &ph);
*x = pw / 100.0F;
*y = ph / 100.0F;
}
static void game_print(drawing *dr, const game_state *state, const game_ui *ui,
int tilesize)
{
const int w = state->shared->params.w;
const int h = state->shared->params.h;
int c, i;
bool borders;
/* Ick: fake up `ds->tilesize' for macro expansion purposes */
game_drawstate *ds = game_new_drawstate(dr, state);
game_set_size(dr, ds, NULL, tilesize);
c = print_mono_colour(dr, 1); assert(c == COL_BACKGROUND);
c = print_mono_colour(dr, 0); assert(c == COL_GRID);
c = print_mono_colour(dr, 1); assert(c == COL_HIGHLIGHT);
c = print_mono_colour(dr, 1); assert(c == COL_CORRECT);
c = print_mono_colour(dr, 1); assert(c == COL_ERROR);
c = print_mono_colour(dr, 0); assert(c == COL_USER);
/*
* Border.
*/
draw_rect(dr, BORDER - BORDER_WIDTH, BORDER - BORDER_WIDTH,
w*TILE_SIZE + 2*BORDER_WIDTH + 1,
h*TILE_SIZE + 2*BORDER_WIDTH + 1,
COL_GRID);
/*
* We'll draw borders between the ominoes iff the grid is not
* pristine. So scan it to see if it is.
*/
borders = false;
for (i = 0; i < w*h; i++)
if (state->board[i] && !state->shared->clues[i])
borders = true;
/*
* Draw grid.
*/
print_line_width(dr, TILE_SIZE / 64);
draw_grid(dr, ds, state, NULL, false, borders, false);
/*
* Clean up.
*/
game_free_drawstate(dr, ds);
}
#ifdef COMBINED
#define thegame filling
#endif
const struct game thegame = {
"Filling", "games.filling", "filling",
default_params,
game_fetch_preset, NULL,
decode_params,
encode_params,
free_params,
dup_params,
true, game_configure, custom_params,
validate_params,
new_game_desc,
validate_desc,
new_game,
dup_game,
free_game,
true, solve_game,
true, game_can_format_as_text_now, game_text_format,
NULL, NULL, /* get_prefs, set_prefs */
new_ui,
free_ui,
NULL, /* encode_ui */
NULL, /* decode_ui */
game_request_keys,
game_changed_state,
current_key_label,
interpret_move,
execute_move,
PREFERRED_TILE_SIZE, game_compute_size, game_set_size,
game_colours,
game_new_drawstate,
game_free_drawstate,
game_redraw,
game_anim_length,
game_flash_length,
game_get_cursor_location,
game_status,
true, false, game_print_size, game_print,
false, /* wants_statusbar */
false, NULL, /* timing_state */
REQUIRE_NUMPAD, /* flags */
};
#ifdef STANDALONE_SOLVER /* solver? hah! */
int main(int argc, char **argv) {
while (*++argv) {
game_params *params;
game_state *state;
char *par;
char *desc;
for (par = desc = *argv; *desc != '\0' && *desc != ':'; ++desc);
if (*desc == '\0') {
fprintf(stderr, "bad puzzle id: %s", par);
continue;
}
*desc++ = '\0';
params = snew(game_params);
decode_params(params, par);
state = new_game(NULL, params, desc);
if (solver(state->board, params->w, params->h, NULL))
printf("%s:%s: solvable\n", par, desc);
else
printf("%s:%s: not solvable\n", par, desc);
}
return 0;
}
#endif
/* vim: set shiftwidth=4 tabstop=8: */