ref: 2e214d740cc9ea2c8061713b0d944f1f29374206
dir: /slant.c/
/*
* slant.c: Puzzle from nikoli.co.jp involving drawing a diagonal
* line through each square of a grid.
*/
/*
* In this puzzle you have a grid of squares, each of which must
* contain a diagonal line; you also have clue numbers placed at
* _points_ of that grid, which means there's a (w+1) x (h+1) array
* of possible clue positions.
*
* I'm therefore going to adopt a rigid convention throughout this
* source file of using w and h for the dimensions of the grid of
* squares, and W and H for the dimensions of the grid of points.
* Thus, W == w+1 and H == h+1 always.
*
* Clue arrays will be W*H `signed char's, and the clue at each
* point will be a number from 0 to 4, or -1 if there's no clue.
*
* Solution arrays will be W*H `signed char's, and the number at
* each point will be +1 for a forward slash (/), -1 for a
* backslash (\), and 0 for unknown.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <ctype.h>
#include <math.h>
#include "puzzles.h"
enum {
COL_BACKGROUND,
COL_GRID,
COL_INK,
NCOLOURS
};
struct game_params {
int w, h;
};
typedef struct game_clues {
int w, h;
signed char *clues;
int *dsf; /* scratch space for completion check */
int refcount;
} game_clues;
struct game_state {
struct game_params p;
game_clues *clues;
signed char *soln;
int completed;
int used_solve; /* used to suppress completion flash */
};
static game_params *default_params(void)
{
game_params *ret = snew(game_params);
ret->w = ret->h = 8;
return ret;
}
static const struct game_params slant_presets[] = {
{5, 5},
{8, 8},
{12, 10},
};
static int game_fetch_preset(int i, char **name, game_params **params)
{
game_params *ret;
char str[80];
if (i < 0 || i >= lenof(slant_presets))
return FALSE;
ret = snew(game_params);
*ret = slant_presets[i];
sprintf(str, "%dx%d", ret->w, ret->h);
*name = dupstr(str);
*params = ret;
return TRUE;
}
static void free_params(game_params *params)
{
sfree(params);
}
static game_params *dup_params(game_params *params)
{
game_params *ret = snew(game_params);
*ret = *params; /* structure 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') {
string++;
ret->h = atoi(string);
}
}
static char *encode_params(game_params *params, int full)
{
char data[256];
sprintf(data, "%dx%d", params->w, params->h);
return dupstr(data);
}
static config_item *game_configure(game_params *params)
{
config_item *ret;
char buf[80];
ret = snewn(3, config_item);
ret[0].name = "Width";
ret[0].type = C_STRING;
sprintf(buf, "%d", params->w);
ret[0].sval = dupstr(buf);
ret[0].ival = 0;
ret[1].name = "Height";
ret[1].type = C_STRING;
sprintf(buf, "%d", params->h);
ret[1].sval = dupstr(buf);
ret[1].ival = 0;
ret[2].name = NULL;
ret[2].type = C_END;
ret[2].sval = NULL;
ret[2].ival = 0;
return ret;
}
static game_params *custom_params(config_item *cfg)
{
game_params *ret = snew(game_params);
ret->w = atoi(cfg[0].sval);
ret->h = atoi(cfg[1].sval);
return ret;
}
static char *validate_params(game_params *params, int full)
{
/*
* (At least at the time of writing this comment) The grid
* generator is actually capable of handling even zero grid
* dimensions without crashing. Puzzles with a zero-area grid
* are a bit boring, though, because they're already solved :-)
*/
if (params->w < 1 || params->h < 1)
return "Width and height must both be at least one";
return NULL;
}
/*
* Utility function used by both the solver and the filled-grid
* generator.
*/
static void fill_square(int w, int h, int y, int x, int v,
signed char *soln, int *dsf)
{
int W = w+1 /*, H = h+1 */;
soln[y*w+x] = v;
if (v < 0)
dsf_merge(dsf, y*W+x, (y+1)*W+(x+1));
else
dsf_merge(dsf, y*W+(x+1), (y+1)*W+x);
}
/*
* Scratch space for solver.
*/
struct solver_scratch {
int *dsf;
};
static struct solver_scratch *new_scratch(int w, int h)
{
int W = w+1, H = h+1;
struct solver_scratch *ret = snew(struct solver_scratch);
ret->dsf = snewn(W*H, int);
return ret;
}
static void free_scratch(struct solver_scratch *sc)
{
sfree(sc->dsf);
sfree(sc);
}
/*
* Solver. Returns 0 for impossibility, 1 for success, 2 for
* ambiguity or failure to converge.
*/
static int slant_solve(int w, int h, const signed char *clues,
signed char *soln, struct solver_scratch *sc)
{
int W = w+1, H = h+1;
int x, y, i;
int done_something;
/*
* Clear the output.
*/
memset(soln, 0, w*h);
/*
* Establish a disjoint set forest for tracking connectedness
* between grid points.
*/
for (i = 0; i < W*H; i++)
sc->dsf[i] = i; /* initially all distinct */
/*
* Repeatedly try to deduce something until we can't.
*/
do {
done_something = FALSE;
/*
* Any clue point with the number of remaining lines equal
* to zero or to the number of remaining undecided
* neighbouring squares can be filled in completely.
*/
for (y = 0; y < H; y++)
for (x = 0; x < W; x++) {
int nu, nl, v, c;
if ((c = clues[y*W+x]) < 0)
continue;
/*
* We have a clue point. Count up the number of
* undecided neighbours, and also the number of
* lines already present.
*/
nu = 0;
nl = c;
if (x > 0 && y > 0 && (v = soln[(y-1)*w+(x-1)]) != +1)
v == 0 ? nu++ : nl--;
if (x > 0 && y < h && (v = soln[y*w+(x-1)]) != -1)
v == 0 ? nu++ : nl--;
if (x < w && y > 0 && (v = soln[(y-1)*w+x]) != -1)
v == 0 ? nu++ : nl--;
if (x < w && y < h && (v = soln[y*w+x]) != +1)
v == 0 ? nu++ : nl--;
/*
* Check the counts.
*/
if (nl < 0 || nl > nu) {
/*
* No consistent value for this at all!
*/
return 0; /* impossible */
}
if (nu > 0 && (nl == 0 || nl == nu)) {
#ifdef SOLVER_DIAGNOSTICS
printf("%s around clue point at %d,%d\n",
nl ? "filling" : "emptying", x, y);
#endif
if (x > 0 && y > 0 && soln[(y-1)*w+(x-1)] == 0)
fill_square(w, h, y-1, x-1, (nl ? -1 : +1), soln,
sc->dsf);
if (x > 0 && y < h && soln[y*w+(x-1)] == 0)
fill_square(w, h, y, x-1, (nl ? +1 : -1), soln,
sc->dsf);
if (x < w && y > 0 && soln[(y-1)*w+x] == 0)
fill_square(w, h, y-1, x, (nl ? +1 : -1), soln,
sc->dsf);
if (x < w && y < h && soln[y*w+x] == 0)
fill_square(w, h, y, x, (nl ? -1 : +1), soln,
sc->dsf);
done_something = TRUE;
}
}
if (done_something)
continue;
/*
* Failing that, we now apply the second condition, which
* is that no square may be filled in such a way as to form
* a loop.
*/
for (y = 0; y < h; y++)
for (x = 0; x < w; x++) {
int fs, bs;
if (soln[y*w+x])
continue; /* got this one already */
fs = (dsf_canonify(sc->dsf, y*W+x) ==
dsf_canonify(sc->dsf, (y+1)*W+(x+1)));
bs = (dsf_canonify(sc->dsf, (y+1)*W+x) ==
dsf_canonify(sc->dsf, y*W+(x+1)));
if (fs && bs) {
/*
* Loop avoidance leaves no consistent value
* for this at all!
*/
return 0; /* impossible */
}
if (fs) {
/*
* Top left and bottom right corners of this
* square are already connected, which means we
* aren't allowed to put a backslash in here.
*/
#ifdef SOLVER_DIAGNOSTICS
printf("placing / in %d,%d by loop avoidance\n", x, y);
#endif
fill_square(w, h, y, x, +1, soln, sc->dsf);
done_something = TRUE;
} else if (bs) {
/*
* Top right and bottom left corners of this
* square are already connected, which means we
* aren't allowed to put a forward slash in
* here.
*/
#ifdef SOLVER_DIAGNOSTICS
printf("placing \\ in %d,%d by loop avoidance\n", x, y);
#endif
fill_square(w, h, y, x, -1, soln, sc->dsf);
done_something = TRUE;
}
}
} while (done_something);
/*
* Solver can make no more progress. See if the grid is full.
*/
for (i = 0; i < w*h; i++)
if (!soln[i])
return 2; /* failed to converge */
return 1; /* success */
}
/*
* Filled-grid generator.
*/
static void slant_generate(int w, int h, signed char *soln, random_state *rs)
{
int W = w+1, H = h+1;
int x, y, i;
int *dsf, *indices;
/*
* Clear the output.
*/
memset(soln, 0, w*h);
/*
* Establish a disjoint set forest for tracking connectedness
* between grid points.
*/
dsf = snewn(W*H, int);
for (i = 0; i < W*H; i++)
dsf[i] = i; /* initially all distinct */
/*
* Prepare a list of the squares in the grid, and fill them in
* in a random order.
*/
indices = snewn(w*h, int);
for (i = 0; i < w*h; i++)
indices[i] = i;
shuffle(indices, w*h, sizeof(*indices), rs);
/*
* Fill in each one in turn.
*/
for (i = 0; i < w*h; i++) {
int fs, bs, v;
y = indices[i] / w;
x = indices[i] % w;
fs = (dsf_canonify(dsf, y*W+x) ==
dsf_canonify(dsf, (y+1)*W+(x+1)));
bs = (dsf_canonify(dsf, (y+1)*W+x) ==
dsf_canonify(dsf, y*W+(x+1)));
/*
* It isn't possible to get into a situation where we
* aren't allowed to place _either_ type of slash in a
* square.
*
* Proof (thanks to Gareth Taylor):
*
* If it were possible, it would have to be because there
* was an existing path (not using this square) between the
* top-left and bottom-right corners of this square, and
* another between the other two. These two paths would
* have to cross at some point.
*
* Obviously they can't cross in the middle of a square, so
* they must cross by sharing a point in common. But this
* isn't possible either: if you chessboard-colour all the
* points on the grid, you find that any continuous
* diagonal path is entirely composed of points of the same
* colour. And one of our two hypothetical paths is between
* two black points, and the other is between two white
* points - therefore they can have no point in common. []
*/
assert(!(fs && bs));
v = fs ? +1 : bs ? -1 : 2 * random_upto(rs, 2) - 1;
fill_square(w, h, y, x, v, soln, dsf);
}
sfree(indices);
sfree(dsf);
}
static char *new_game_desc(game_params *params, random_state *rs,
char **aux, int interactive)
{
int w = params->w, h = params->h, W = w+1, H = h+1;
signed char *soln, *tmpsoln, *clues;
int *clueindices;
struct solver_scratch *sc;
int x, y, v, i;
char *desc;
soln = snewn(w*h, signed char);
tmpsoln = snewn(w*h, signed char);
clues = snewn(W*H, signed char);
clueindices = snewn(W*H, int);
sc = new_scratch(w, h);
do {
/*
* Create the filled grid.
*/
slant_generate(w, h, soln, rs);
/*
* Fill in the complete set of clues.
*/
for (y = 0; y < H; y++)
for (x = 0; x < W; x++) {
v = 0;
if (x > 0 && y > 0 && soln[(y-1)*w+(x-1)] == -1) v++;
if (x > 0 && y < h && soln[y*w+(x-1)] == +1) v++;
if (x < w && y > 0 && soln[(y-1)*w+x] == +1) v++;
if (x < w && y < h && soln[y*w+x] == -1) v++;
clues[y*W+x] = v;
}
} while (slant_solve(w, h, clues, tmpsoln, sc) != 1);
/*
* Remove as many clues as possible while retaining solubility.
*/
for (i = 0; i < W*H; i++)
clueindices[i] = i;
shuffle(clueindices, W*H, sizeof(*clueindices), rs);
for (i = 0; i < W*H; i++) {
y = clueindices[i] / W;
x = clueindices[i] % W;
v = clues[y*W+x];
clues[y*W+x] = -1;
if (slant_solve(w, h, clues, tmpsoln, sc) != 1)
clues[y*W+x] = v; /* put it back */
}
/*
* Now we have the clue set as it will be presented to the
* user. Encode it in a game desc.
*/
{
char *p;
int run, i;
desc = snewn(W*H+1, char);
p = desc;
run = 0;
for (i = 0; i <= W*H; i++) {
int n = (i < W*H ? clues[i] : -2);
if (n == -1)
run++;
else {
if (run) {
while (run > 0) {
int c = 'a' - 1 + run;
if (run > 26)
c = 'z';
*p++ = c;
run -= c - ('a' - 1);
}
}
if (n >= 0)
*p++ = '0' + n;
run = 0;
}
}
assert(p - desc <= W*H);
*p++ = '\0';
desc = sresize(desc, p - desc, char);
}
/*
* Encode the solution as an aux_info.
*/
{
char *auxbuf;
*aux = auxbuf = snewn(w*h+1, char);
for (i = 0; i < w*h; i++)
auxbuf[i] = soln[i] < 0 ? '\\' : '/';
auxbuf[w*h] = '\0';
}
free_scratch(sc);
sfree(clueindices);
sfree(clues);
sfree(tmpsoln);
sfree(soln);
return desc;
}
static char *validate_desc(game_params *params, char *desc)
{
int w = params->w, h = params->h, W = w+1, H = h+1;
int area = W*H;
int squares = 0;
while (*desc) {
int n = *desc++;
if (n >= 'a' && n <= 'z') {
squares += n - 'a' + 1;
} else if (n >= '0' && n <= '4') {
squares++;
} else
return "Invalid character in game description";
}
if (squares < area)
return "Not enough data to fill grid";
if (squares > area)
return "Too much data to fit in grid";
return NULL;
}
static game_state *new_game(midend_data *me, game_params *params, char *desc)
{
int w = params->w, h = params->h, W = w+1, H = h+1;
game_state *state = snew(game_state);
int area = W*H;
int squares = 0;
state->p = *params;
state->soln = snewn(w*h, signed char);
memset(state->soln, 0, w*h);
state->completed = state->used_solve = FALSE;
state->clues = snew(game_clues);
state->clues->w = w;
state->clues->h = h;
state->clues->clues = snewn(W*H, signed char);
state->clues->refcount = 1;
state->clues->dsf = snewn(W*H, int);
memset(state->clues->clues, -1, W*H);
while (*desc) {
int n = *desc++;
if (n >= 'a' && n <= 'z') {
squares += n - 'a' + 1;
} else if (n >= '0' && n <= '4') {
state->clues->clues[squares++] = n - '0';
} else
assert(!"can't get here");
}
assert(squares == area);
return state;
}
static game_state *dup_game(game_state *state)
{
int w = state->p.w, h = state->p.h;
game_state *ret = snew(game_state);
ret->p = state->p;
ret->clues = state->clues;
ret->clues->refcount++;
ret->completed = state->completed;
ret->used_solve = state->used_solve;
ret->soln = snewn(w*h, signed char);
memcpy(ret->soln, state->soln, w*h);
return ret;
}
static void free_game(game_state *state)
{
sfree(state->soln);
assert(state->clues);
if (--state->clues->refcount <= 0) {
sfree(state->clues->clues);
sfree(state->clues->dsf);
sfree(state->clues);
}
sfree(state);
}
static int check_completion(game_state *state)
{
int w = state->p.w, h = state->p.h, W = w+1, H = h+1;
int i, x, y;
/*
* Establish a disjoint set forest for tracking connectedness
* between grid points. Use the dsf scratch space in the shared
* clues structure, to avoid mallocing too often.
*/
for (i = 0; i < W*H; i++)
state->clues->dsf[i] = i; /* initially all distinct */
/*
* Now go through the grid checking connectedness. While we're
* here, also check that everything is filled in.
*/
for (y = 0; y < h; y++)
for (x = 0; x < w; x++) {
int i1, i2;
if (state->soln[y*w+x] == 0)
return FALSE;
if (state->soln[y*w+x] < 0) {
i1 = y*W+x;
i2 = (y+1)*W+(x+1);
} else {
i1 = (y+1)*W+x;
i2 = y*W+(x+1);
}
/*
* Our edge connects i1 with i2. If they're already
* connected, return failure. Otherwise, link them.
*/
if (dsf_canonify(state->clues->dsf, i1) ==
dsf_canonify(state->clues->dsf, i2))
return FALSE;
else
dsf_merge(state->clues->dsf, i1, i2);
}
/*
* The grid is _a_ valid grid; let's see if it matches the
* clues.
*/
for (y = 0; y < H; y++)
for (x = 0; x < W; x++) {
int v, c;
if ((c = state->clues->clues[y*W+x]) < 0)
continue;
v = 0;
if (x > 0 && y > 0 && state->soln[(y-1)*w+(x-1)] == -1) v++;
if (x > 0 && y < h && state->soln[y*w+(x-1)] == +1) v++;
if (x < w && y > 0 && state->soln[(y-1)*w+x] == +1) v++;
if (x < w && y < h && state->soln[y*w+x] == -1) v++;
if (c != v)
return FALSE;
}
return TRUE;
}
static char *solve_game(game_state *state, game_state *currstate,
char *aux, char **error)
{
int w = state->p.w, h = state->p.h;
signed char *soln;
int bs, ret;
int free_soln = FALSE;
char *move, buf[80];
int movelen, movesize;
int x, y;
if (aux) {
/*
* If we already have the solution, save ourselves some
* time.
*/
soln = (signed char *)aux;
bs = (signed char)'\\';
free_soln = FALSE;
} else {
struct solver_scratch *sc = new_scratch(w, h);
soln = snewn(w*h, signed char);
bs = -1;
ret = slant_solve(w, h, state->clues->clues, soln, sc);
free_scratch(sc);
if (ret != 1) {
sfree(soln);
if (ret == 0)
*error = "This puzzle is not self-consistent";
else
*error = "Unable to find a unique solution for this puzzle";
return NULL;
}
free_soln = TRUE;
}
/*
* Construct a move string which turns the current state into
* the solved state.
*/
movesize = 256;
move = snewn(movesize, char);
movelen = 0;
move[movelen++] = 'S';
move[movelen] = '\0';
for (y = 0; y < h; y++)
for (x = 0; x < w; x++) {
int v = (soln[y*w+x] == bs ? -1 : +1);
if (state->soln[y*w+x] != v) {
int len = sprintf(buf, ";%c%d,%d", (int)(v < 0 ? '\\' : '/'), x, y);
if (movelen + len >= movesize) {
movesize = movelen + len + 256;
move = sresize(move, movesize, char);
}
strcpy(move + movelen, buf);
movelen += len;
}
}
if (free_soln)
sfree(soln);
return move;
}
static char *game_text_format(game_state *state)
{
int w = state->p.w, h = state->p.h, W = w+1, H = h+1;
int x, y, len;
char *ret, *p;
/*
* There are h+H rows of w+W columns.
*/
len = (h+H) * (w+W+1) + 1;
ret = snewn(len, char);
p = ret;
for (y = 0; y < H; y++) {
for (x = 0; x < W; x++) {
if (state->clues->clues[y*W+x] >= 0)
*p++ = state->clues->clues[y*W+x] + '0';
else
*p++ = '+';
if (x < w)
*p++ = '-';
}
*p++ = '\n';
if (y < h) {
for (x = 0; x < W; x++) {
*p++ = '|';
if (x < w) {
if (state->soln[y*w+x] != 0)
*p++ = (state->soln[y*w+x] < 0 ? '\\' : '/');
else
*p++ = ' ';
}
}
*p++ = '\n';
}
}
*p++ = '\0';
assert(p - ret == len);
return ret;
}
static game_ui *new_ui(game_state *state)
{
return NULL;
}
static void free_ui(game_ui *ui)
{
}
static char *encode_ui(game_ui *ui)
{
return NULL;
}
static void decode_ui(game_ui *ui, char *encoding)
{
}
static void game_changed_state(game_ui *ui, game_state *oldstate,
game_state *newstate)
{
}
#define PREFERRED_TILESIZE 32
#define TILESIZE (ds->tilesize)
#define BORDER TILESIZE
#define CLUE_RADIUS (TILESIZE / 3)
#define CLUE_TEXTSIZE (TILESIZE / 2)
#define COORD(x) ( (x) * TILESIZE + BORDER )
#define FROMCOORD(x) ( ((x) - BORDER + TILESIZE) / TILESIZE - 1 )
#define FLASH_TIME 0.30F
/*
* Bit fields in the `grid' and `todraw' elements of the drawstate.
*/
#define BACKSLASH 0x0001
#define FORWSLASH 0x0002
#define L_T 0x0004
#define L_B 0x0008
#define T_L 0x0010
#define T_R 0x0020
#define R_T 0x0040
#define R_B 0x0080
#define B_L 0x0100
#define B_R 0x0200
#define C_TL 0x0400
#define C_TR 0x0800
#define C_BL 0x1000
#define C_BR 0x2000
#define FLASH 0x4000
struct game_drawstate {
int tilesize;
int started;
int *grid;
int *todraw;
};
static char *interpret_move(game_state *state, game_ui *ui, game_drawstate *ds,
int x, int y, int button)
{
int w = state->p.w, h = state->p.h;
if (button == LEFT_BUTTON || button == RIGHT_BUTTON) {
int v;
char buf[80];
x = FROMCOORD(x);
y = FROMCOORD(y);
if (x < 0 || y < 0 || x >= w || y >= h)
return NULL;
if (button == LEFT_BUTTON) {
/*
* Left-clicking cycles blank -> \ -> / -> blank.
*/
v = state->soln[y*w+x] - 1;
if (v == -2)
v = +1;
} else {
/*
* Right-clicking cycles blank -> / -> \ -> blank.
*/
v = state->soln[y*w+x] + 1;
if (v == +2)
v = -1;
}
sprintf(buf, "%c%d,%d", (int)(v==-1 ? '\\' : v==+1 ? '/' : 'C'), x, y);
return dupstr(buf);
}
return NULL;
}
static game_state *execute_move(game_state *state, char *move)
{
int w = state->p.w, h = state->p.h;
char c;
int x, y, n;
game_state *ret = dup_game(state);
while (*move) {
c = *move;
if (c == 'S') {
ret->used_solve = TRUE;
move++;
} else if (c == '\\' || c == '/' || c == 'C') {
move++;
if (sscanf(move, "%d,%d%n", &x, &y, &n) != 2 ||
x < 0 || y < 0 || x >= w || y >= h) {
free_game(ret);
return NULL;
}
ret->soln[y*w+x] = (c == '\\' ? -1 : c == '/' ? +1 : 0);
move += n;
} else {
free_game(ret);
return NULL;
}
if (*move == ';')
move++;
else if (*move) {
free_game(ret);
return NULL;
}
}
if (!ret->completed)
ret->completed = check_completion(ret);
return ret;
}
/* ----------------------------------------------------------------------
* Drawing routines.
*/
static void game_compute_size(game_params *params, int tilesize,
int *x, int *y)
{
/* fool the macros */
struct dummy { int tilesize; } dummy = { tilesize }, *ds = &dummy;
*x = 2 * BORDER + params->w * TILESIZE + 1;
*y = 2 * BORDER + params->h * TILESIZE + 1;
}
static void game_set_size(game_drawstate *ds, game_params *params,
int tilesize)
{
ds->tilesize = tilesize;
}
static float *game_colours(frontend *fe, game_state *state, int *ncolours)
{
float *ret = snewn(3 * NCOLOURS, float);
frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]);
ret[COL_GRID * 3 + 0] = ret[COL_BACKGROUND * 3 + 0] * 0.7F;
ret[COL_GRID * 3 + 1] = ret[COL_BACKGROUND * 3 + 1] * 0.7F;
ret[COL_GRID * 3 + 2] = ret[COL_BACKGROUND * 3 + 2] * 0.7F;
ret[COL_INK * 3 + 0] = 0.0F;
ret[COL_INK * 3 + 1] = 0.0F;
ret[COL_INK * 3 + 2] = 0.0F;
*ncolours = NCOLOURS;
return ret;
}
static game_drawstate *game_new_drawstate(game_state *state)
{
int w = state->p.w, h = state->p.h;
int i;
struct game_drawstate *ds = snew(struct game_drawstate);
ds->tilesize = 0;
ds->started = FALSE;
ds->grid = snewn(w*h, int);
ds->todraw = snewn(w*h, int);
for (i = 0; i < w*h; i++)
ds->grid[i] = ds->todraw[i] = -1;
return ds;
}
static void game_free_drawstate(game_drawstate *ds)
{
sfree(ds->todraw);
sfree(ds->grid);
sfree(ds);
}
static void draw_clue(frontend *fe, game_drawstate *ds,
int x, int y, int v)
{
char p[2];
if (v < 0)
return;
p[0] = v + '0';
p[1] = '\0';
draw_circle(fe, COORD(x), COORD(y), CLUE_RADIUS,
COL_BACKGROUND, COL_INK);
draw_text(fe, COORD(x), COORD(y), FONT_VARIABLE,
CLUE_TEXTSIZE, ALIGN_VCENTRE|ALIGN_HCENTRE,
COL_INK, p);
}
static void draw_tile(frontend *fe, game_drawstate *ds, game_clues *clues,
int x, int y, int v)
{
int w = clues->w /*, h = clues->h*/, W = w+1 /*, H = h+1 */;
int xx, yy;
clip(fe, COORD(x), COORD(y), TILESIZE+1, TILESIZE+1);
draw_rect(fe, COORD(x), COORD(y), TILESIZE, TILESIZE,
(v & FLASH) ? COL_GRID : COL_BACKGROUND);
/*
* Draw the grid lines.
*/
draw_line(fe, COORD(x), COORD(y), COORD(x+1), COORD(y), COL_GRID);
draw_line(fe, COORD(x), COORD(y+1), COORD(x+1), COORD(y+1), COL_GRID);
draw_line(fe, COORD(x), COORD(y), COORD(x), COORD(y+1), COL_GRID);
draw_line(fe, COORD(x+1), COORD(y), COORD(x+1), COORD(y+1), COL_GRID);
/*
* Draw the slash.
*/
if (v & BACKSLASH) {
draw_line(fe, COORD(x), COORD(y), COORD(x+1), COORD(y+1), COL_INK);
draw_line(fe, COORD(x)+1, COORD(y), COORD(x+1), COORD(y+1)-1,
COL_INK);
draw_line(fe, COORD(x), COORD(y)+1, COORD(x+1)-1, COORD(y+1),
COL_INK);
} else if (v & FORWSLASH) {
draw_line(fe, COORD(x+1), COORD(y), COORD(x), COORD(y+1), COL_INK);
draw_line(fe, COORD(x+1)-1, COORD(y), COORD(x), COORD(y+1)-1,
COL_INK);
draw_line(fe, COORD(x+1), COORD(y)+1, COORD(x)+1, COORD(y+1),
COL_INK);
}
/*
* Draw dots on the grid corners that appear if a slash is in a
* neighbouring cell.
*/
if (v & L_T)
draw_rect(fe, COORD(x), COORD(y)+1, 1, 1, COL_INK);
if (v & L_B)
draw_rect(fe, COORD(x), COORD(y+1)-1, 1, 1, COL_INK);
if (v & R_T)
draw_rect(fe, COORD(x+1), COORD(y)+1, 1, 1, COL_INK);
if (v & R_B)
draw_rect(fe, COORD(x+1), COORD(y+1)-1, 1, 1, COL_INK);
if (v & T_L)
draw_rect(fe, COORD(x)+1, COORD(y), 1, 1, COL_INK);
if (v & T_R)
draw_rect(fe, COORD(x+1)-1, COORD(y), 1, 1, COL_INK);
if (v & B_L)
draw_rect(fe, COORD(x)+1, COORD(y+1), 1, 1, COL_INK);
if (v & B_R)
draw_rect(fe, COORD(x+1)-1, COORD(y+1), 1, 1, COL_INK);
if (v & C_TL)
draw_rect(fe, COORD(x), COORD(y), 1, 1, COL_INK);
if (v & C_TR)
draw_rect(fe, COORD(x+1), COORD(y), 1, 1, COL_INK);
if (v & C_BL)
draw_rect(fe, COORD(x), COORD(y+1), 1, 1, COL_INK);
if (v & C_BR)
draw_rect(fe, COORD(x+1), COORD(y+1), 1, 1, COL_INK);
/*
* And finally the clues at the corners.
*/
for (xx = x; xx <= x+1; xx++)
for (yy = y; yy <= y+1; yy++)
draw_clue(fe, ds, xx, yy, clues->clues[yy*W+xx]);
unclip(fe);
draw_update(fe, COORD(x), COORD(y), TILESIZE+1, TILESIZE+1);
}
static void game_redraw(frontend *fe, game_drawstate *ds, game_state *oldstate,
game_state *state, int dir, game_ui *ui,
float animtime, float flashtime)
{
int w = state->p.w, h = state->p.h, W = w+1, H = h+1;
int x, y;
int flashing;
if (flashtime > 0)
flashing = (int)(flashtime * 3 / FLASH_TIME) != 1;
else
flashing = FALSE;
if (!ds->started) {
int ww, wh;
game_compute_size(&state->p, TILESIZE, &ww, &wh);
draw_rect(fe, 0, 0, ww, wh, COL_BACKGROUND);
draw_update(fe, 0, 0, ww, wh);
/*
* Draw any clues on the very edges (since normal tile
* redraw won't draw the bits outside the grid boundary).
*/
for (y = 0; y < H; y++) {
draw_clue(fe, ds, 0, y, state->clues->clues[y*W+0]);
draw_clue(fe, ds, w, y, state->clues->clues[y*W+w]);
}
for (x = 0; x < W; x++) {
draw_clue(fe, ds, x, 0, state->clues->clues[0*W+x]);
draw_clue(fe, ds, x, h, state->clues->clues[h*W+x]);
}
ds->started = TRUE;
}
/*
* Loop over the grid and work out where all the slashes are.
* We need to do this because a slash in one square affects the
* drawing of the next one along.
*/
for (y = 0; y < h; y++)
for (x = 0; x < w; x++)
ds->todraw[y*w+x] = flashing ? FLASH : 0;
for (y = 0; y < h; y++) {
for (x = 0; x < w; x++) {
if (state->soln[y*w+x] < 0) {
ds->todraw[y*w+x] |= BACKSLASH;
if (x > 0)
ds->todraw[y*w+(x-1)] |= R_T | C_TR;
if (x+1 < w)
ds->todraw[y*w+(x+1)] |= L_B | C_BL;
if (y > 0)
ds->todraw[(y-1)*w+x] |= B_L | C_BL;
if (y+1 < h)
ds->todraw[(y+1)*w+x] |= T_R | C_TR;
if (x > 0 && y > 0)
ds->todraw[(y-1)*w+(x-1)] |= C_BR;
if (x+1 < w && y+1 < h)
ds->todraw[(y+1)*w+(x+1)] |= C_TL;
} else if (state->soln[y*w+x] > 0) {
ds->todraw[y*w+x] |= FORWSLASH;
if (x > 0)
ds->todraw[y*w+(x-1)] |= R_B | C_BR;
if (x+1 < w)
ds->todraw[y*w+(x+1)] |= L_T | C_TL;
if (y > 0)
ds->todraw[(y-1)*w+x] |= B_R | C_BR;
if (y+1 < h)
ds->todraw[(y+1)*w+x] |= T_L | C_TL;
if (x > 0 && y+1 < h)
ds->todraw[(y+1)*w+(x-1)] |= C_TR;
if (x+1 < w && y > 0)
ds->todraw[(y-1)*w+(x+1)] |= C_BL;
}
}
}
/*
* Now go through and draw the grid squares.
*/
for (y = 0; y < h; y++) {
for (x = 0; x < w; x++) {
if (ds->todraw[y*w+x] != ds->grid[y*w+x]) {
draw_tile(fe, ds, state->clues, x, y, ds->todraw[y*w+x]);
ds->grid[y*w+x] = ds->todraw[y*w+x];
}
}
}
}
static float game_anim_length(game_state *oldstate, game_state *newstate,
int dir, game_ui *ui)
{
return 0.0F;
}
static float game_flash_length(game_state *oldstate, game_state *newstate,
int dir, game_ui *ui)
{
if (!oldstate->completed && newstate->completed &&
!oldstate->used_solve && !newstate->used_solve)
return FLASH_TIME;
return 0.0F;
}
static int game_wants_statusbar(void)
{
return FALSE;
}
static int game_timing_state(game_state *state, game_ui *ui)
{
return TRUE;
}
#ifdef COMBINED
#define thegame slant
#endif
const struct game thegame = {
"Slant", "games.slant",
default_params,
game_fetch_preset,
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_text_format,
new_ui,
free_ui,
encode_ui,
decode_ui,
game_changed_state,
interpret_move,
execute_move,
PREFERRED_TILESIZE, game_compute_size, game_set_size,
game_colours,
game_new_drawstate,
game_free_drawstate,
game_redraw,
game_anim_length,
game_flash_length,
game_wants_statusbar,
FALSE, game_timing_state,
0, /* mouse_priorities */
};