ref: 819277148315fd5b5cc987e4b4e440e5b2bd2dad
dir: /pearl.c/
/*
* pearl.c: Nikoli's `Masyu' puzzle.
*/
/*
* TODO:
*
* - The current keyboard cursor mechanism works well on ordinary PC
* keyboards, but for platforms with only arrow keys and a select
* button or two, we may at some point need a simpler one which can
* handle 'x' markings without needing shift keys. For instance, a
* cursor with twice the grid resolution, so that it can range
* across face centres, edge centres and vertices; 'clicks' on face
* centres begin a drag as currently, clicks on edges toggle
* markings, and clicks on vertices are ignored (but it would be
* too confusing not to let the cursor rest on them). But I'm
* pretty sure that would be less pleasant to play on a full
* keyboard, so probably a #ifdef would be the thing.
*
* - Generation is still pretty slow, due to difficulty coming up in
* the first place with a loop that makes a soluble puzzle even
* with all possible clues filled in.
* + A possible alternative strategy to further tuning of the
* existing loop generator would be to throw the entire
* mechanism out and instead write a different generator from
* scratch which evolves the solution along with the puzzle:
* place a few clues, nail down a bit of the loop, place another
* clue, nail down some more, etc. However, I don't have a
* detailed plan for any such mechanism, so it may be a pipe
* dream.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <ctype.h>
#include <limits.h>
#ifdef NO_TGMATH_H
# include <math.h>
#else
# include <tgmath.h>
#endif
#include "puzzles.h"
#include "grid.h"
#include "loopgen.h"
#define SWAP(i,j) do { int swaptmp = (i); (i) = (j); (j) = swaptmp; } while (0)
#define NOCLUE 0
#define CORNER 1
#define STRAIGHT 2
#define R 1
#define U 2
#define L 4
#define D 8
#define DX(d) ( ((d)==R) - ((d)==L) )
#define DY(d) ( ((d)==D) - ((d)==U) )
#define F(d) (((d << 2) | (d >> 2)) & 0xF)
#define C(d) (((d << 3) | (d >> 1)) & 0xF)
#define A(d) (((d << 1) | (d >> 3)) & 0xF)
#define LR (L | R)
#define RL (R | L)
#define UD (U | D)
#define DU (D | U)
#define LU (L | U)
#define UL (U | L)
#define LD (L | D)
#define DL (D | L)
#define RU (R | U)
#define UR (U | R)
#define RD (R | D)
#define DR (D | R)
#define BLANK 0
#define UNKNOWN 15
#define bLR (1 << LR)
#define bRL (1 << RL)
#define bUD (1 << UD)
#define bDU (1 << DU)
#define bLU (1 << LU)
#define bUL (1 << UL)
#define bLD (1 << LD)
#define bDL (1 << DL)
#define bRU (1 << RU)
#define bUR (1 << UR)
#define bRD (1 << RD)
#define bDR (1 << DR)
#define bBLANK (1 << BLANK)
enum {
COL_BACKGROUND, COL_HIGHLIGHT, COL_LOWLIGHT,
COL_CURSOR_BACKGROUND = COL_LOWLIGHT,
COL_BLACK, COL_WHITE,
COL_ERROR, COL_GRID, COL_FLASH,
COL_DRAGON, COL_DRAGOFF,
NCOLOURS
};
/* Macro ickery copied from slant.c */
#define DIFFLIST(A) \
A(EASY,Easy,e) \
A(TRICKY,Tricky,t)
#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) DIFFCOUNT };
static char const *const pearl_diffnames[] = { DIFFLIST(TITLE) "(count)" };
static char const pearl_diffchars[] = DIFFLIST(ENCODE);
#define DIFFCONFIG DIFFLIST(CONFIG)
struct game_params {
int w, h;
int difficulty;
bool nosolve; /* XXX remove me! */
};
struct shared_state {
int w, h, sz;
char *clues; /* size w*h */
int refcnt;
};
#define INGRID(state, gx, gy) ((gx) >= 0 && (gx) < (state)->shared->w && \
(gy) >= 0 && (gy) < (state)->shared->h)
struct game_state {
struct shared_state *shared;
char *lines; /* size w*h: lines placed */
char *errors; /* size w*h: errors detected */
char *marks; /* size w*h: 'no line here' marks placed. */
bool completed, used_solve;
};
#define DEFAULT_PRESET 3
static const struct game_params pearl_presets[] = {
{6, 6, DIFF_EASY},
{6, 6, DIFF_TRICKY},
{8, 8, DIFF_EASY},
{8, 8, DIFF_TRICKY},
{10, 10, DIFF_EASY},
{10, 10, DIFF_TRICKY},
{12, 8, DIFF_EASY},
{12, 8, DIFF_TRICKY},
};
static game_params *default_params(void)
{
game_params *ret = snew(game_params);
*ret = pearl_presets[DEFAULT_PRESET];
ret->nosolve = false;
return ret;
}
static bool game_fetch_preset(int i, char **name, game_params **params)
{
game_params *ret;
char buf[64];
if (i < 0 || i >= lenof(pearl_presets)) return false;
ret = default_params();
*ret = pearl_presets[i]; /* struct copy */
*params = ret;
sprintf(buf, "%dx%d %s",
pearl_presets[i].w, pearl_presets[i].h,
pearl_diffnames[pearl_presets[i].difficulty]);
*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; /* 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);
while (*string && isdigit((unsigned char)*string)) string++;
}
ret->difficulty = DIFF_EASY;
if (*string == 'd') {
int i;
string++;
for (i = 0; i < DIFFCOUNT; i++)
if (*string == pearl_diffchars[i])
ret->difficulty = i;
if (*string) string++;
}
ret->nosolve = false;
if (*string == 'n') {
ret->nosolve = true;
string++;
}
}
static char *encode_params(const game_params *params, bool full)
{
char buf[256];
sprintf(buf, "%dx%d", params->w, params->h);
if (full)
sprintf(buf + strlen(buf), "d%c%s",
pearl_diffchars[params->difficulty],
params->nosolve ? "n" : "");
return dupstr(buf);
}
static config_item *game_configure(const game_params *params)
{
config_item *ret;
char buf[64];
ret = snewn(5, 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 = "Difficulty";
ret[2].type = C_CHOICES;
ret[2].u.choices.choicenames = DIFFCONFIG;
ret[2].u.choices.selected = params->difficulty;
ret[3].name = "Allow unsoluble";
ret[3].type = C_BOOLEAN;
ret[3].u.boolean.bval = params->nosolve;
ret[4].name = NULL;
ret[4].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);
ret->difficulty = cfg[2].u.choices.selected;
ret->nosolve = cfg[3].u.boolean.bval;
return ret;
}
static const char *validate_params(const game_params *params, bool full)
{
if (params->w < 5) return "Width must be at least five";
if (params->h < 5) return "Height must be at least five";
if (params->w > INT_MAX / params->h)
return "Width times height must not be unreasonably large";
if (params->difficulty < 0 || params->difficulty >= DIFFCOUNT)
return "Unknown difficulty level";
if (params->difficulty >= DIFF_TRICKY && params->w + params->h < 11)
return "Width or height must be at least six for Tricky";
return NULL;
}
/* ----------------------------------------------------------------------
* Solver.
*/
static int pearl_solve(int w, int h, char *clues, char *result,
int difficulty, bool partial)
{
int W = 2*w+1, H = 2*h+1;
short *workspace;
DSF *dsf;
int *dsfsize;
int x, y, b, d;
int ret = -1;
/*
* workspace[(2*y+1)*W+(2*x+1)] indicates the possible nature
* of the square (x,y), as a logical OR of bitfields.
*
* workspace[(2*y)*W+(2*x+1)], for x odd and y even, indicates
* whether the horizontal edge between (x,y) and (x+1,y) is
* connected (1), disconnected (2) or unknown (3).
*
* workspace[(2*y+1)*W+(2*x)], indicates the same about the
* vertical edge between (x,y) and (x,y+1).
*
* Initially, every square is considered capable of being in
* any of the seven possible states (two straights, four
* corners and empty), except those corresponding to clue
* squares which are more restricted.
*
* Initially, all edges are unknown, except the ones around the
* grid border which are known to be disconnected.
*/
workspace = snewn(W*H, short);
for (x = 0; x < W*H; x++)
workspace[x] = 0;
/* Square states */
for (y = 0; y < h; y++)
for (x = 0; x < w; x++)
switch (clues[y*w+x]) {
case CORNER:
workspace[(2*y+1)*W+(2*x+1)] = bLU|bLD|bRU|bRD;
break;
case STRAIGHT:
workspace[(2*y+1)*W+(2*x+1)] = bLR|bUD;
break;
default:
workspace[(2*y+1)*W+(2*x+1)] = bLR|bUD|bLU|bLD|bRU|bRD|bBLANK;
break;
}
/* Horizontal edges */
for (y = 0; y <= h; y++)
for (x = 0; x < w; x++)
workspace[(2*y)*W+(2*x+1)] = (y==0 || y==h ? 2 : 3);
/* Vertical edges */
for (y = 0; y < h; y++)
for (x = 0; x <= w; x++)
workspace[(2*y+1)*W+(2*x)] = (x==0 || x==w ? 2 : 3);
/*
* We maintain a dsf of connected squares, together with a
* count of the size of each equivalence class.
*/
dsf = dsf_new(w*h);
dsfsize = snewn(w*h, int);
/*
* Now repeatedly try to find something we can do.
*/
while (1) {
bool done_something = false;
#ifdef SOLVER_DIAGNOSTICS
for (y = 0; y < H; y++) {
for (x = 0; x < W; x++)
printf("%*x", (x&1) ? 5 : 2, workspace[y*W+x]);
printf("\n");
}
#endif
/*
* Go through the square state words, and discard any
* square state which is inconsistent with known facts
* about the edges around the square.
*/
for (y = 0; y < h; y++)
for (x = 0; x < w; x++) {
for (b = 0; b < 0xD; b++)
if (workspace[(2*y+1)*W+(2*x+1)] & (1<<b)) {
/*
* If any edge of this square is known to
* be connected when state b would require
* it disconnected, or vice versa, discard
* the state.
*/
for (d = 1; d <= 8; d += d) {
int ex = 2*x+1 + DX(d), ey = 2*y+1 + DY(d);
if (workspace[ey*W+ex] ==
((b & d) ? 2 : 1)) {
workspace[(2*y+1)*W+(2*x+1)] &= ~(1<<b);
#ifdef SOLVER_DIAGNOSTICS
printf("edge (%d,%d)-(%d,%d) rules out state"
" %d for square (%d,%d)\n",
ex/2, ey/2, (ex+1)/2, (ey+1)/2,
b, x, y);
#endif
done_something = true;
break;
}
}
}
/*
* Consistency check: each square must have at
* least one state left!
*/
if (!workspace[(2*y+1)*W+(2*x+1)]) {
#ifdef SOLVER_DIAGNOSTICS
printf("edge check at (%d,%d): inconsistency\n", x, y);
#endif
ret = 0;
goto cleanup;
}
}
/*
* Now go through the states array again, and nail down any
* unknown edge if one of its neighbouring squares makes it
* known.
*/
for (y = 0; y < h; y++)
for (x = 0; x < w; x++) {
int edgeor = 0, edgeand = 15;
for (b = 0; b < 0xD; b++)
if (workspace[(2*y+1)*W+(2*x+1)] & (1<<b)) {
edgeor |= b;
edgeand &= b;
}
/*
* Now any bit clear in edgeor marks a disconnected
* edge, and any bit set in edgeand marks a
* connected edge.
*/
/* First check consistency: neither bit is both! */
if (edgeand & ~edgeor) {
#ifdef SOLVER_DIAGNOSTICS
printf("square check at (%d,%d): inconsistency\n", x, y);
#endif
ret = 0;
goto cleanup;
}
for (d = 1; d <= 8; d += d) {
int ex = 2*x+1 + DX(d), ey = 2*y+1 + DY(d);
if (!(edgeor & d) && workspace[ey*W+ex] == 3) {
workspace[ey*W+ex] = 2;
done_something = true;
#ifdef SOLVER_DIAGNOSTICS
printf("possible states of square (%d,%d) force edge"
" (%d,%d)-(%d,%d) to be disconnected\n",
x, y, ex/2, ey/2, (ex+1)/2, (ey+1)/2);
#endif
} else if ((edgeand & d) && workspace[ey*W+ex] == 3) {
workspace[ey*W+ex] = 1;
done_something = true;
#ifdef SOLVER_DIAGNOSTICS
printf("possible states of square (%d,%d) force edge"
" (%d,%d)-(%d,%d) to be connected\n",
x, y, ex/2, ey/2, (ex+1)/2, (ey+1)/2);
#endif
}
}
}
if (done_something)
continue;
/*
* Now for longer-range clue-based deductions (using the
* rules that a corner clue must connect to two straight
* squares, and a straight clue must connect to at least
* one corner square).
*/
for (y = 0; y < h; y++)
for (x = 0; x < w; x++)
switch (clues[y*w+x]) {
case CORNER:
for (d = 1; d <= 8; d += d) {
int ex = 2*x+1 + DX(d), ey = 2*y+1 + DY(d);
int fx = ex + DX(d), fy = ey + DY(d);
int type = d | F(d);
if (workspace[ey*W+ex] == 1) {
/*
* If a corner clue is connected on any
* edge, then we can immediately nail
* down the square beyond that edge as
* being a straight in the appropriate
* direction.
*/
if (workspace[fy*W+fx] != (1<<type)) {
workspace[fy*W+fx] = (1<<type);
done_something = true;
#ifdef SOLVER_DIAGNOSTICS
printf("corner clue at (%d,%d) forces square "
"(%d,%d) into state %d\n", x, y,
fx/2, fy/2, type);
#endif
}
} else if (workspace[ey*W+ex] == 3) {
/*
* Conversely, if a corner clue is
* separated by an unknown edge from a
* square which _cannot_ be a straight
* in the appropriate direction, we can
* mark that edge as disconnected.
*/
if (!(workspace[fy*W+fx] & (1<<type))) {
workspace[ey*W+ex] = 2;
done_something = true;
#ifdef SOLVER_DIAGNOSTICS
printf("corner clue at (%d,%d), plus square "
"(%d,%d) not being state %d, "
"disconnects edge (%d,%d)-(%d,%d)\n",
x, y, fx/2, fy/2, type,
ex/2, ey/2, (ex+1)/2, (ey+1)/2);
#endif
}
}
}
break;
case STRAIGHT:
/*
* If a straight clue is between two squares
* neither of which is capable of being a
* corner connected to it, then the straight
* clue cannot point in that direction.
*/
for (d = 1; d <= 2; d += d) {
int fx = 2*x+1 + 2*DX(d), fy = 2*y+1 + 2*DY(d);
int gx = 2*x+1 - 2*DX(d), gy = 2*y+1 - 2*DY(d);
int type = d | F(d);
if (!(workspace[(2*y+1)*W+(2*x+1)] & (1<<type)))
continue;
if (!(workspace[fy*W+fx] & ((1<<(F(d)|A(d))) |
(1<<(F(d)|C(d))))) &&
!(workspace[gy*W+gx] & ((1<<( d |A(d))) |
(1<<( d |C(d)))))) {
workspace[(2*y+1)*W+(2*x+1)] &= ~(1<<type);
done_something = true;
#ifdef SOLVER_DIAGNOSTICS
printf("straight clue at (%d,%d) cannot corner at "
"(%d,%d) or (%d,%d) so is not state %d\n",
x, y, fx/2, fy/2, gx/2, gy/2, type);
#endif
}
}
/*
* If a straight clue with known direction is
* connected on one side to a known straight,
* then on the other side it must be a corner.
*/
for (d = 1; d <= 8; d += d) {
int fx = 2*x+1 + 2*DX(d), fy = 2*y+1 + 2*DY(d);
int gx = 2*x+1 - 2*DX(d), gy = 2*y+1 - 2*DY(d);
int type = d | F(d);
if (workspace[(2*y+1)*W+(2*x+1)] != (1<<type))
continue;
if (!(workspace[fy*W+fx] &~ (bLR|bUD)) &&
(workspace[gy*W+gx] &~ (bLU|bLD|bRU|bRD))) {
workspace[gy*W+gx] &= (bLU|bLD|bRU|bRD);
done_something = true;
#ifdef SOLVER_DIAGNOSTICS
printf("straight clue at (%d,%d) connecting to "
"straight at (%d,%d) makes (%d,%d) a "
"corner\n", x, y, fx/2, fy/2, gx/2, gy/2);
#endif
}
}
break;
}
if (done_something)
continue;
/*
* Now detect shortcut loops.
*/
{
int nonblanks, loopclass;
dsf_reinit(dsf);
for (x = 0; x < w*h; x++)
dsfsize[x] = 1;
/*
* First go through the edge entries and update the dsf
* of which squares are connected to which others. We
* also track the number of squares in each equivalence
* class, and count the overall number of
* known-non-blank squares.
*
* In the process of doing this, we must notice if a
* loop has already been formed. If it has, we blank
* out any square which isn't part of that loop
* (failing a consistency check if any such square does
* not have BLANK as one of its remaining options) and
* exit the deduction loop with success.
*/
nonblanks = 0;
loopclass = -1;
for (y = 1; y < H-1; y++)
for (x = 1; x < W-1; x++)
if ((y ^ x) & 1) {
/*
* (x,y) are the workspace coordinates of
* an edge field. Compute the normal-space
* coordinates of the squares it connects.
*/
int ax = (x-1)/2, ay = (y-1)/2, ac = ay*w+ax;
int bx = x/2, by = y/2, bc = by*w+bx;
/*
* If the edge is connected, do the dsf
* thing.
*/
if (workspace[y*W+x] == 1) {
int ae, be;
ae = dsf_canonify(dsf, ac);
be = dsf_canonify(dsf, bc);
if (ae == be) {
/*
* We have a loop!
*/
if (loopclass != -1) {
/*
* In fact, we have two
* separate loops, which is
* doom.
*/
#ifdef SOLVER_DIAGNOSTICS
printf("two loops found in grid!\n");
#endif
ret = 0;
goto cleanup;
}
loopclass = ae;
} else {
/*
* Merge the two equivalence
* classes.
*/
int size = dsfsize[ae] + dsfsize[be];
dsf_merge(dsf, ac, bc);
ae = dsf_canonify(dsf, ac);
dsfsize[ae] = size;
}
}
} else if ((y & x) & 1) {
/*
* (x,y) are the workspace coordinates of a
* square field. If the square is
* definitely not blank, count it.
*/
if (!(workspace[y*W+x] & bBLANK))
nonblanks++;
}
/*
* If we discovered an existing loop above, we must now
* blank every square not part of it, and exit the main
* deduction loop.
*/
if (loopclass != -1) {
#ifdef SOLVER_DIAGNOSTICS
printf("loop found in grid!\n");
#endif
for (y = 0; y < h; y++)
for (x = 0; x < w; x++)
if (dsf_canonify(dsf, y*w+x) != loopclass) {
if (workspace[(y*2+1)*W+(x*2+1)] & bBLANK) {
workspace[(y*2+1)*W+(x*2+1)] = bBLANK;
} else {
/*
* This square is not part of the
* loop, but is known non-blank. We
* have goofed.
*/
#ifdef SOLVER_DIAGNOSTICS
printf("non-blank square (%d,%d) found outside"
" loop!\n", x, y);
#endif
ret = 0;
goto cleanup;
}
}
/*
* And we're done.
*/
ret = 1;
break;
}
/* Further deductions are considered 'tricky'. */
if (difficulty == DIFF_EASY) goto done_deductions;
/*
* Now go through the workspace again and mark any edge
* which would cause a shortcut loop (i.e. would
* connect together two squares in the same equivalence
* class, and that equivalence class does not contain
* _all_ the known-non-blank squares currently in the
* grid) as disconnected. Also, mark any _square state_
* which would cause a shortcut loop as disconnected.
*/
for (y = 1; y < H-1; y++)
for (x = 1; x < W-1; x++)
if ((y ^ x) & 1) {
/*
* (x,y) are the workspace coordinates of
* an edge field. Compute the normal-space
* coordinates of the squares it connects.
*/
int ax = (x-1)/2, ay = (y-1)/2, ac = ay*w+ax;
int bx = x/2, by = y/2, bc = by*w+bx;
/*
* If the edge is currently unknown, and
* sits between two squares in the same
* equivalence class, and the size of that
* class is less than nonblanks, then
* connecting this edge would be a shortcut
* loop and so we must not do so.
*/
if (workspace[y*W+x] == 3) {
int ae, be;
ae = dsf_canonify(dsf, ac);
be = dsf_canonify(dsf, bc);
if (ae == be) {
/*
* We have a loop. Is it a shortcut?
*/
if (dsfsize[ae] < nonblanks) {
/*
* Yes! Mark this edge disconnected.
*/
workspace[y*W+x] = 2;
done_something = true;
#ifdef SOLVER_DIAGNOSTICS
printf("edge (%d,%d)-(%d,%d) would create"
" a shortcut loop, hence must be"
" disconnected\n", x/2, y/2,
(x+1)/2, (y+1)/2);
#endif
}
}
}
} else if ((y & x) & 1) {
/*
* (x,y) are the workspace coordinates of a
* square field. Go through its possible
* (non-blank) states and see if any gives
* rise to a shortcut loop.
*
* This is slightly fiddly, because we have
* to check whether this square is already
* part of the same equivalence class as
* the things it's joining.
*/
int ae = dsf_canonify(dsf, (y/2)*w+(x/2));
for (b = 2; b < 0xD; b++)
if (workspace[y*W+x] & (1<<b)) {
/*
* Find the equivalence classes of
* the two squares this one would
* connect if it were in this
* state.
*/
int e = -1;
for (d = 1; d <= 8; d += d) if (b & d) {
int xx = x/2 + DX(d), yy = y/2 + DY(d);
int ee = dsf_canonify(dsf, yy*w+xx);
if (e == -1)
ee = e;
else if (e != ee)
e = -2;
}
if (e >= 0) {
/*
* This square state would form
* a loop on equivalence class
* e. Measure the size of that
* loop, and see if it's a
* shortcut.
*/
int loopsize = dsfsize[e];
if (e != ae)
loopsize++;/* add the square itself */
if (loopsize < nonblanks) {
/*
* It is! Mark this square
* state invalid.
*/
workspace[y*W+x] &= ~(1<<b);
done_something = true;
#ifdef SOLVER_DIAGNOSTICS
printf("square (%d,%d) would create a "
"shortcut loop in state %d, "
"hence cannot be\n",
x/2, y/2, b);
#endif
}
}
}
}
}
done_deductions:
if (done_something)
continue;
/*
* If we reach here, there is nothing left we can do.
* Return 2 for ambiguous puzzle.
*/
ret = 2;
break;
}
cleanup:
/*
* If ret = 1 then we've successfully achieved a solution. This
* means that we expect every square to be nailed down to
* exactly one possibility. If this is the case, or if the caller
* asked for a partial solution anyway, transcribe those
* possibilities into the result array.
*/
if (ret == 1 || partial) {
for (y = 0; y < h; y++) {
for (x = 0; x < w; x++) {
for (b = 0; b < 0xD; b++)
if (workspace[(2*y+1)*W+(2*x+1)] == (1<<b)) {
result[y*w+x] = b;
break;
}
if (ret == 1) assert(b < 0xD); /* we should have had a break by now */
}
}
/*
* Ensure we haven't left the _data structure_ inconsistent,
* regardless of the consistency of the _puzzle_. In
* particular, we should never have marked one square as
* linked to its neighbour if the neighbour is not
* reciprocally linked back to the original square.
*
* This can happen if we get part way through solving an
* impossible puzzle and then give up trying to make further
* progress. So here we fix it up to avoid confusing the rest
* of the game.
*/
for (y = 0; y < h; y++) {
for (x = 0; x < w; x++) {
for (d = 1; d <= 8; d += d) {
int nx = x + DX(d), ny = y + DY(d);
int rlink;
if (0 <= nx && nx < w && 0 <= ny && ny < h)
rlink = result[ny*w+nx] & F(d);
else
rlink = 0; /* off-board squares don't link back */
/* If other square doesn't link to us, don't link to it */
if (!rlink)
result[y*w+x] &= ~d;
}
}
}
}
sfree(dsfsize);
dsf_free(dsf);
sfree(workspace);
assert(ret >= 0);
return ret;
}
/* ----------------------------------------------------------------------
* Loop generator.
*/
/*
* We use the loop generator code from loopy, hard-coding to a square
* grid of the appropriate size. Knowing the grid layout and the tile
* size we can shrink that to our small grid and then make our line
* layout from the face colour info.
*
* We provide a bias function to the loop generator which tries to
* bias in favour of loops with more scope for Pearl black clues. This
* seems to improve the success rate of the puzzle generator, in that
* such loops have a better chance of being soluble with all valid
* clues put in.
*/
struct pearl_loopgen_bias_ctx {
/*
* Our bias function counts the number of 'black clue' corners
* (i.e. corners adjacent to two straights) in both the
* BLACK/nonBLACK and WHITE/nonWHITE boundaries. In order to do
* this, we must:
*
* - track the edges that are part of each of those loops
* - track the types of vertex in each loop (corner, straight,
* none)
* - track the current black-clue status of each vertex in each
* loop.
*
* Each of these chunks of data is updated incrementally from the
* previous one, to avoid slowdown due to the bias function
* rescanning the whole grid every time it's called.
*
* So we need a lot of separate arrays, plus a tdq for each one,
* and we must repeat it all twice for the BLACK and WHITE
* boundaries.
*/
struct pearl_loopgen_bias_ctx_boundary {
int colour; /* FACE_WHITE or FACE_BLACK */
bool *edges; /* is each edge part of the loop? */
tdq *edges_todo;
char *vertextypes; /* bits 0-3 == outgoing edge bitmap;
* bit 4 set iff corner clue.
* Hence, 0 means non-vertex;
* nonzero but bit 4 zero = straight. */
int *neighbour[2]; /* indices of neighbour vertices in loop */
tdq *vertextypes_todo;
char *blackclues; /* is each vertex a black clue site? */
tdq *blackclues_todo;
} boundaries[2]; /* boundaries[0]=WHITE, [1]=BLACK */
char *faces; /* remember last-seen colour of each face */
tdq *faces_todo;
int score;
grid *g;
};
static int pearl_loopgen_bias(void *vctx, char *board, int face)
{
struct pearl_loopgen_bias_ctx *ctx = (struct pearl_loopgen_bias_ctx *)vctx;
grid *g = ctx->g;
int oldface, newface;
int i, j, k;
tdq_add(ctx->faces_todo, face);
while ((j = tdq_remove(ctx->faces_todo)) >= 0) {
oldface = ctx->faces[j];
ctx->faces[j] = newface = board[j];
for (i = 0; i < 2; i++) {
struct pearl_loopgen_bias_ctx_boundary *b = &ctx->boundaries[i];
int c = b->colour;
/*
* If the face has changed either from or to colour c, we need
* to reprocess the edges for this boundary.
*/
if (oldface == c || newface == c) {
grid_face *f = g->faces[face];
for (k = 0; k < f->order; k++)
tdq_add(b->edges_todo, f->edges[k]->index);
}
}
}
for (i = 0; i < 2; i++) {
struct pearl_loopgen_bias_ctx_boundary *b = &ctx->boundaries[i];
int c = b->colour;
/*
* Go through the to-do list of edges. For each edge, decide
* anew whether it's part of this boundary or not. Any edge
* that changes state has to have both its endpoints put on
* the vertextypes_todo list.
*/
while ((j = tdq_remove(b->edges_todo)) >= 0) {
grid_edge *e = g->edges[j];
int fc1 = e->face1 ? board[e->face1->index] : FACE_BLACK;
int fc2 = e->face2 ? board[e->face2->index] : FACE_BLACK;
bool oldedge = b->edges[j];
bool newedge = (fc1==c) ^ (fc2==c);
if (oldedge != newedge) {
b->edges[j] = newedge;
tdq_add(b->vertextypes_todo, e->dot1->index);
tdq_add(b->vertextypes_todo, e->dot2->index);
}
}
/*
* Go through the to-do list of vertices whose types need
* refreshing. For each one, decide whether it's a corner, a
* straight, or a vertex not in the loop, and in the former
* two cases also work out the indices of its neighbour
* vertices along the loop. Any vertex that changes state must
* be put back on the to-do list for deciding if it's a black
* clue site, and so must its two new neighbours _and_ its two
* old neighbours.
*/
while ((j = tdq_remove(b->vertextypes_todo)) >= 0) {
grid_dot *d = g->dots[j];
int neighbours[2], type = 0, n = 0;
for (k = 0; k < d->order; k++) {
grid_edge *e = d->edges[k];
grid_dot *d2 = (e->dot1 == d ? e->dot2 : e->dot1);
/* dir == 0,1,2,3 for an edge going L,U,R,D */
int dir = (d->y == d2->y) + 2*(d->x+d->y > d2->x+d2->y);
int ei = e->index;
if (b->edges[ei]) {
type |= 1 << dir;
neighbours[n] = d2->index;
n++;
}
}
/*
* Decide if it's a corner, and set the corner flag if so.
*/
if (type != 0 && type != 0x5 && type != 0xA)
type |= 0x10;
if (type != b->vertextypes[j]) {
/*
* Recompute old neighbours, if any.
*/
if (b->vertextypes[j]) {
tdq_add(b->blackclues_todo, b->neighbour[0][j]);
tdq_add(b->blackclues_todo, b->neighbour[1][j]);
}
/*
* Recompute this vertex.
*/
tdq_add(b->blackclues_todo, j);
b->vertextypes[j] = type;
/*
* Recompute new neighbours, if any.
*/
if (b->vertextypes[j]) {
b->neighbour[0][j] = neighbours[0];
b->neighbour[1][j] = neighbours[1];
tdq_add(b->blackclues_todo, b->neighbour[0][j]);
tdq_add(b->blackclues_todo, b->neighbour[1][j]);
}
}
}
/*
* Go through the list of vertices which we must check to see
* if they're black clue sites. Each one is a black clue site
* iff it is a corner and its loop neighbours are non-corners.
* Adjust the running total of black clues we've counted.
*/
while ((j = tdq_remove(b->blackclues_todo)) >= 0) {
ctx->score -= b->blackclues[j];
b->blackclues[j] = ((b->vertextypes[j] & 0x10) &&
!((b->vertextypes[b->neighbour[0][j]] |
b->vertextypes[b->neighbour[1][j]])
& 0x10));
ctx->score += b->blackclues[j];
}
}
return ctx->score;
}
static void pearl_loopgen(int w, int h, char *lines, random_state *rs, grid *g)
{
char *board = snewn(g->num_faces, char);
int i, s = g->tilesize;
struct pearl_loopgen_bias_ctx biasctx;
memset(lines, 0, w*h);
/*
* Initialise the context for the bias function. Initially we fill
* all the to-do lists, so that the first call will scan
* everything; thereafter the lists stay empty so we make
* incremental changes.
*/
biasctx.g = g;
biasctx.faces = snewn(g->num_faces, char);
biasctx.faces_todo = tdq_new(g->num_faces);
tdq_fill(biasctx.faces_todo);
biasctx.score = 0;
memset(biasctx.faces, FACE_GREY, g->num_faces);
for (i = 0; i < 2; i++) {
biasctx.boundaries[i].edges = snewn(g->num_edges, bool);
memset(biasctx.boundaries[i].edges, 0, g->num_edges * sizeof(bool));
biasctx.boundaries[i].edges_todo = tdq_new(g->num_edges);
tdq_fill(biasctx.boundaries[i].edges_todo);
biasctx.boundaries[i].vertextypes = snewn(g->num_dots, char);
memset(biasctx.boundaries[i].vertextypes, 0, g->num_dots);
biasctx.boundaries[i].neighbour[0] = snewn(g->num_dots, int);
biasctx.boundaries[i].neighbour[1] = snewn(g->num_dots, int);
biasctx.boundaries[i].vertextypes_todo = tdq_new(g->num_dots);
tdq_fill(biasctx.boundaries[i].vertextypes_todo);
biasctx.boundaries[i].blackclues = snewn(g->num_dots, char);
memset(biasctx.boundaries[i].blackclues, 0, g->num_dots);
biasctx.boundaries[i].blackclues_todo = tdq_new(g->num_dots);
tdq_fill(biasctx.boundaries[i].blackclues_todo);
}
biasctx.boundaries[0].colour = FACE_WHITE;
biasctx.boundaries[1].colour = FACE_BLACK;
generate_loop(g, board, rs, pearl_loopgen_bias, &biasctx);
sfree(biasctx.faces);
tdq_free(biasctx.faces_todo);
for (i = 0; i < 2; i++) {
sfree(biasctx.boundaries[i].edges);
tdq_free(biasctx.boundaries[i].edges_todo);
sfree(biasctx.boundaries[i].vertextypes);
sfree(biasctx.boundaries[i].neighbour[0]);
sfree(biasctx.boundaries[i].neighbour[1]);
tdq_free(biasctx.boundaries[i].vertextypes_todo);
sfree(biasctx.boundaries[i].blackclues);
tdq_free(biasctx.boundaries[i].blackclues_todo);
}
for (i = 0; i < g->num_edges; i++) {
grid_edge *e = g->edges[i];
enum face_colour c1 = FACE_COLOUR(e->face1);
enum face_colour c2 = FACE_COLOUR(e->face2);
assert(c1 != FACE_GREY);
assert(c2 != FACE_GREY);
if (c1 != c2) {
/* This grid edge is on the loop: lay line along it */
int x1 = e->dot1->x/s, y1 = e->dot1->y/s;
int x2 = e->dot2->x/s, y2 = e->dot2->y/s;
/* (x1,y1) and (x2,y2) are now in our grid coords (0-w,0-h). */
if (x1 == x2) {
if (y1 > y2) SWAP(y1,y2);
assert(y1+1 == y2);
lines[y1*w+x1] |= D;
lines[y2*w+x1] |= U;
} else if (y1 == y2) {
if (x1 > x2) SWAP(x1,x2);
assert(x1+1 == x2);
lines[y1*w+x1] |= R;
lines[y1*w+x2] |= L;
} else
assert(!"grid with diagonal coords?!");
}
}
sfree(board);
#if defined LOOPGEN_DIAGNOSTICS && !defined GENERATION_DIAGNOSTICS
printf("as returned:\n");
for (y = 0; y < h; y++) {
for (x = 0; x < w; x++) {
int type = lines[y*w+x];
char s[5], *p = s;
if (type & L) *p++ = 'L';
if (type & R) *p++ = 'R';
if (type & U) *p++ = 'U';
if (type & D) *p++ = 'D';
*p = '\0';
printf("%3s", s);
}
printf("\n");
}
printf("\n");
#endif
}
static int new_clues(const game_params *params, random_state *rs,
char *clues, char *grid_out)
{
int w = params->w, h = params->h, diff = params->difficulty;
int ngen = 0, x, y, d, ret, i;
grid *g = grid_new(GRID_SQUARE, w-1, h-1, NULL);
/*
* Difficulty exception: 5x5 Tricky is not generable (the
* generator will spin forever trying) and so we fudge it to Easy.
*/
if (w == 5 && h == 5 && diff > DIFF_EASY)
diff = DIFF_EASY;
while (1) {
ngen++;
pearl_loopgen(w, h, grid_out, rs, g);
#ifdef GENERATION_DIAGNOSTICS
printf("grid array:\n");
for (y = 0; y < h; y++) {
for (x = 0; x < w; x++) {
int type = grid_out[y*w+x];
char s[5], *p = s;
if (type & L) *p++ = 'L';
if (type & R) *p++ = 'R';
if (type & U) *p++ = 'U';
if (type & D) *p++ = 'D';
*p = '\0';
printf("%2s ", s);
}
printf("\n");
}
printf("\n");
#endif
/*
* Set up the maximal clue array.
*/
for (y = 0; y < h; y++)
for (x = 0; x < w; x++) {
int type = grid_out[y*w+x];
clues[y*w+x] = NOCLUE;
if ((bLR|bUD) & (1 << type)) {
/*
* This is a straight; see if it's a viable
* candidate for a straight clue. It qualifies if
* at least one of the squares it connects to is a
* corner.
*/
for (d = 1; d <= 8; d += d) if (type & d) {
int xx = x + DX(d), yy = y + DY(d);
assert(xx >= 0 && xx < w && yy >= 0 && yy < h);
if ((bLU|bLD|bRU|bRD) & (1 << grid_out[yy*w+xx]))
break;
}
if (d <= 8) /* we found one */
clues[y*w+x] = STRAIGHT;
} else if ((bLU|bLD|bRU|bRD) & (1 << type)) {
/*
* This is a corner; see if it's a viable candidate
* for a corner clue. It qualifies if all the
* squares it connects to are straights.
*/
for (d = 1; d <= 8; d += d) if (type & d) {
int xx = x + DX(d), yy = y + DY(d);
assert(xx >= 0 && xx < w && yy >= 0 && yy < h);
if (!((bLR|bUD) & (1 << grid_out[yy*w+xx])))
break;
}
if (d > 8) /* we didn't find a counterexample */
clues[y*w+x] = CORNER;
}
}
#ifdef GENERATION_DIAGNOSTICS
printf("clue array:\n");
for (y = 0; y < h; y++) {
for (x = 0; x < w; x++) {
printf("%c", " *O"[(unsigned char)clues[y*w+x]]);
}
printf("\n");
}
printf("\n");
#endif
if (!params->nosolve) {
int *cluespace, *straights, *corners;
int nstraights, ncorners, nstraightpos, ncornerpos;
/*
* See if we can solve the puzzle just like this.
*/
ret = pearl_solve(w, h, clues, grid_out, diff, false);
assert(ret > 0); /* shouldn't be inconsistent! */
if (ret != 1)
continue; /* go round and try again */
/*
* Check this puzzle isn't too easy.
*/
if (diff > DIFF_EASY) {
ret = pearl_solve(w, h, clues, grid_out, diff-1, false);
assert(ret > 0);
if (ret == 1)
continue; /* too easy: try again */
}
/*
* Now shuffle the grid points and gradually remove the
* clues to find a minimal set which still leaves the
* puzzle soluble.
*
* We preferentially attempt to remove whichever type of
* clue is currently most numerous, to combat a general
* tendency of plain random generation to bias in favour
* of many white clues and few black.
*
* 'nstraights' and 'ncorners' count the number of clues
* of each type currently remaining in the grid;
* 'nstraightpos' and 'ncornerpos' count the clues of each
* type we have left to try to remove. (Clues which we
* have tried and failed to remove are counted by the
* former but not the latter.)
*/
cluespace = snewn(w*h, int);
straights = cluespace;
nstraightpos = 0;
for (i = 0; i < w*h; i++)
if (clues[i] == STRAIGHT)
straights[nstraightpos++] = i;
corners = straights + nstraightpos;
ncornerpos = 0;
for (i = 0; i < w*h; i++)
if (clues[i] == STRAIGHT)
corners[ncornerpos++] = i;
nstraights = nstraightpos;
ncorners = ncornerpos;
shuffle(straights, nstraightpos, sizeof(*straights), rs);
shuffle(corners, ncornerpos, sizeof(*corners), rs);
while (nstraightpos > 0 || ncornerpos > 0) {
int cluepos;
int clue;
/*
* Decide which clue to try to remove next. If both
* types are available, we choose whichever kind is
* currently overrepresented; otherwise we take
* whatever we can get.
*/
if (nstraightpos > 0 && ncornerpos > 0) {
if (nstraights >= ncorners)
cluepos = straights[--nstraightpos];
else
cluepos = straights[--ncornerpos];
} else {
if (nstraightpos > 0)
cluepos = straights[--nstraightpos];
else
cluepos = straights[--ncornerpos];
}
y = cluepos / w;
x = cluepos % w;
clue = clues[y*w+x];
clues[y*w+x] = 0; /* try removing this clue */
ret = pearl_solve(w, h, clues, grid_out, diff, false);
assert(ret > 0);
if (ret != 1)
clues[y*w+x] = clue; /* oops, put it back again */
}
sfree(cluespace);
}
#ifdef FINISHED_PUZZLE
printf("clue array:\n");
for (y = 0; y < h; y++) {
for (x = 0; x < w; x++) {
printf("%c", " *O"[(unsigned char)clues[y*w+x]]);
}
printf("\n");
}
printf("\n");
#endif
break; /* got it */
}
grid_free(g);
debug(("%d %dx%d loops before finished puzzle.\n", ngen, w, h));
return ngen;
}
static char *new_game_desc(const game_params *params, random_state *rs,
char **aux, bool interactive)
{
char *grid, *clues;
char *desc;
int w = params->w, h = params->h, i, j;
grid = snewn(w*h, char);
clues = snewn(w*h, char);
new_clues(params, rs, clues, grid);
desc = snewn(w * h + 1, char);
for (i = j = 0; i < w*h; i++) {
if (clues[i] == NOCLUE && j > 0 &&
desc[j-1] >= 'a' && desc[j-1] < 'z')
desc[j-1]++;
else if (clues[i] == NOCLUE)
desc[j++] = 'a';
else if (clues[i] == CORNER)
desc[j++] = 'B';
else if (clues[i] == STRAIGHT)
desc[j++] = 'W';
}
desc[j] = '\0';
*aux = snewn(w*h+1, char);
for (i = 0; i < w*h; i++)
(*aux)[i] = (grid[i] < 10) ? (grid[i] + '0') : (grid[i] + 'A' - 10);
(*aux)[w*h] = '\0';
sfree(grid);
sfree(clues);
return desc;
}
static const char *validate_desc(const game_params *params, const char *desc)
{
int i, sizesofar;
const int totalsize = params->w * params->h;
sizesofar = 0;
for (i = 0; desc[i]; i++) {
if (desc[i] >= 'a' && desc[i] <= 'z')
sizesofar += desc[i] - 'a' + 1;
else if (desc[i] == 'B' || desc[i] == 'W')
sizesofar++;
else
return "unrecognised character in string";
}
if (sizesofar > totalsize)
return "string too long";
else if (sizesofar < totalsize)
return "string too short";
return NULL;
}
static game_state *new_game(midend *me, const game_params *params,
const char *desc)
{
game_state *state = snew(game_state);
int i, j, sz = params->w*params->h;
state->completed = false;
state->used_solve = false;
state->shared = snew(struct shared_state);
state->shared->w = params->w;
state->shared->h = params->h;
state->shared->sz = sz;
state->shared->refcnt = 1;
state->shared->clues = snewn(sz, char);
for (i = j = 0; desc[i]; i++) {
assert(j < sz);
if (desc[i] >= 'a' && desc[i] <= 'z') {
int n = desc[i] - 'a' + 1;
assert(j + n <= sz);
while (n-- > 0)
state->shared->clues[j++] = NOCLUE;
} else if (desc[i] == 'B') {
state->shared->clues[j++] = CORNER;
} else if (desc[i] == 'W') {
state->shared->clues[j++] = STRAIGHT;
}
}
state->lines = snewn(sz, char);
state->errors = snewn(sz, char);
state->marks = snewn(sz, char);
for (i = 0; i < sz; i++)
state->lines[i] = state->errors[i] = state->marks[i] = BLANK;
return state;
}
static game_state *dup_game(const game_state *state)
{
game_state *ret = snew(game_state);
int sz = state->shared->sz, i;
ret->shared = state->shared;
ret->completed = state->completed;
ret->used_solve = state->used_solve;
++ret->shared->refcnt;
ret->lines = snewn(sz, char);
ret->errors = snewn(sz, char);
ret->marks = snewn(sz, char);
for (i = 0; i < sz; i++) {
ret->lines[i] = state->lines[i];
ret->errors[i] = state->errors[i];
ret->marks[i] = state->marks[i];
}
return ret;
}
static void free_game(game_state *state)
{
assert(state);
if (--state->shared->refcnt == 0) {
sfree(state->shared->clues);
sfree(state->shared);
}
sfree(state->lines);
sfree(state->errors);
sfree(state->marks);
sfree(state);
}
static char nbits[16] = { 0, 1, 1, 2,
1, 2, 2, 3,
1, 2, 2, 3,
2, 3, 3, 4 };
#define NBITS(l) ( ((l) < 0 || (l) > 15) ? 4 : nbits[l] )
#define ERROR_CLUE 16
/* Returns false if the state is invalid. */
static bool dsf_update_completion(game_state *state, int ax, int ay, char dir,
DSF *dsf)
{
int w = state->shared->w /*, h = state->shared->h */;
int ac = ay*w+ax, bx, by, bc;
if (!(state->lines[ac] & dir)) return true; /* no link */
bx = ax + DX(dir); by = ay + DY(dir);
if (!INGRID(state, bx, by))
return false; /* should not have a link off grid */
bc = by*w+bx;
if (!(state->lines[bc] & F(dir)))
return false; /* should have reciprocal link */
if (!(state->lines[bc] & F(dir))) return true;
dsf_merge(dsf, ac, bc);
return true;
}
/* Returns false if the state is invalid. */
static bool check_completion(game_state *state, bool mark)
{
int w = state->shared->w, h = state->shared->h, x, y, i, d;
bool had_error = false;
DSF *dsf;
int *component_state;
int nsilly, nloop, npath, largest_comp, largest_size, total_pathsize;
enum { COMP_NONE, COMP_LOOP, COMP_PATH, COMP_SILLY, COMP_EMPTY };
if (mark) {
for (i = 0; i < w*h; i++) {
state->errors[i] = 0;
}
}
#define ERROR(x,y,e) do { had_error = true; if (mark) state->errors[(y)*w+(x)] |= (e); } while(0)
/*
* Analyse the solution into loops, paths and stranger things.
* Basic strategy here is all the same as in Loopy - see the big
* comment in loopy.c's check_completion() - and for exactly the
* same reasons, since Loopy and Pearl have basically the same
* form of expected solution.
*/
dsf = dsf_new(w*h);
/* Build the dsf. */
for (x = 0; x < w; x++) {
for (y = 0; y < h; y++) {
if (!dsf_update_completion(state, x, y, R, dsf) ||
!dsf_update_completion(state, x, y, D, dsf)) {
dsf_free(dsf);
return false;
}
}
}
/* Initialise a state variable for each connected component. */
component_state = snewn(w*h, int);
for (i = 0; i < w*h; i++) {
if (dsf_canonify(dsf, i) == i)
component_state[i] = COMP_LOOP;
else
component_state[i] = COMP_NONE;
}
/*
* Classify components, and mark errors where a square has more
* than two line segments.
*/
for (x = 0; x < w; x++) {
for (y = 0; y < h; y++) {
int type = state->lines[y*w+x];
int degree = NBITS(type);
int comp = dsf_canonify(dsf, y*w+x);
if (degree > 2) {
ERROR(x,y,type);
component_state[comp] = COMP_SILLY;
} else if (degree == 0) {
component_state[comp] = COMP_EMPTY;
} else if (degree == 1) {
if (component_state[comp] != COMP_SILLY)
component_state[comp] = COMP_PATH;
}
}
}
/* Count the components, and find the largest sensible one. */
nsilly = nloop = npath = 0;
total_pathsize = 0;
largest_comp = largest_size = -1;
for (i = 0; i < w*h; 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 every sensible component that is
* not the largest one.
*/
for (i = 0; i < w*h; i++) {
int comp = dsf_canonify(dsf, i);
if ((component_state[comp] == COMP_PATH &&
-1 != largest_comp) ||
(component_state[comp] == COMP_LOOP &&
comp != largest_comp))
ERROR(i%w, i/w, state->lines[i]);
}
}
/* Now we've finished with the dsf and component states. The only
* thing we'll need to remember later on is whether all edges were
* part of a single loop, for which our counter variables
* nsilly,nloop,npath are enough. */
sfree(component_state);
dsf_free(dsf);
/*
* Check that no clues are contradicted. This code is similar to
* the code that sets up the maximal clue array for any given
* loop.
*/
for (x = 0; x < w; x++) {
for (y = 0; y < h; y++) {
int type = state->lines[y*w+x];
if (state->shared->clues[y*w+x] == CORNER) {
/* Supposed to be a corner: will find a contradiction if
* it actually contains a straight line, or if it touches any
* corners. */
if ((bLR|bUD) & (1 << type)) {
ERROR(x,y,ERROR_CLUE); /* actually straight */
}
for (d = 1; d <= 8; d += d) if (type & d) {
int xx = x + DX(d), yy = y + DY(d);
if (!INGRID(state, xx, yy)) {
ERROR(x,y,d); /* leads off grid */
} else {
if ((bLU|bLD|bRU|bRD) & (1 << state->lines[yy*w+xx])) {
ERROR(x,y,ERROR_CLUE); /* touches corner */
}
}
}
} else if (state->shared->clues[y*w+x] == STRAIGHT) {
/* Supposed to be straight: will find a contradiction if
* it actually contains a corner, or if it only touches
* straight lines. */
if ((bLU|bLD|bRU|bRD) & (1 << type)) {
ERROR(x,y,ERROR_CLUE); /* actually a corner */
}
i = 0;
for (d = 1; d <= 8; d += d) if (type & d) {
int xx = x + DX(d), yy = y + DY(d);
if (!INGRID(state, xx, yy)) {
ERROR(x,y,d); /* leads off grid */
} else {
if ((bLR|bUD) & (1 << state->lines[yy*w+xx]))
i++; /* a straight */
}
}
if (i >= 2 && NBITS(type) >= 2) {
ERROR(x,y,ERROR_CLUE); /* everything touched is straight */
}
}
}
}
if (nloop == 1 && nsilly == 0 && npath == 0) {
/*
* If there's exactly one loop (so that the puzzle is at least
* potentially complete), we need to ensure it hasn't left any
* clue out completely.
*/
for (x = 0; x < w; x++) {
for (y = 0; y < h; y++) {
if (state->lines[y*w+x] == BLANK) {
if (state->shared->clues[y*w+x] != NOCLUE) {
/* the loop doesn't include this clue square! */
ERROR(x, y, ERROR_CLUE);
}
}
}
}
/*
* But if not, then we're done!
*/
if (!had_error)
state->completed = true;
}
return true;
}
/* completion check:
*
* - no clues must be contradicted (highlight clue itself in error if so)
* - if there is a closed loop it must include every line segment laid
* - if there's a smaller closed loop then highlight whole loop as error
* - no square must have more than 2 lines radiating from centre point
* (highlight all lines in that square as error if so)
*/
static char *solve_for_diff(game_state *state, char *old_lines, char *new_lines)
{
int w = state->shared->w, h = state->shared->h, i;
char *move = snewn(w*h*40, char), *p = move;
*p++ = 'S';
for (i = 0; i < w*h; i++) {
if (old_lines[i] != new_lines[i]) {
p += sprintf(p, ";R%d,%d,%d", new_lines[i], i%w, i/w);
}
}
*p++ = '\0';
move = sresize(move, p - move, char);
return move;
}
static char *solve_game(const game_state *state, const game_state *currstate,
const char *aux, const char **error)
{
game_state *solved = dup_game(state);
int i, ret, sz = state->shared->sz;
char *move;
if (aux) {
for (i = 0; i < sz; i++) {
if (aux[i] >= '0' && aux[i] <= '9')
solved->lines[i] = aux[i] - '0';
else if (aux[i] >= 'A' && aux[i] <= 'F')
solved->lines[i] = aux[i] - 'A' + 10;
else {
*error = "invalid char in aux";
move = NULL;
goto done;
}
}
ret = 1;
} else {
/* Try to solve with present (half-solved) state first: if there's no
* solution from there go back to original state. */
ret = pearl_solve(currstate->shared->w, currstate->shared->h,
currstate->shared->clues, solved->lines,
DIFFCOUNT, false);
if (ret < 1)
ret = pearl_solve(state->shared->w, state->shared->h,
state->shared->clues, solved->lines,
DIFFCOUNT, false);
}
if (ret < 1) {
*error = "Unable to find solution";
move = NULL;
} else {
move = solve_for_diff(solved, currstate->lines, solved->lines);
}
done:
free_game(solved);
return move;
}
static bool game_can_format_as_text_now(const game_params *params)
{
return true;
}
static char *game_text_format(const game_state *state)
{
int w = state->shared->w, h = state->shared->h, cw = 4, ch = 2;
int gw = cw*(w-1) + 2, gh = ch*(h-1) + 1, len = gw * gh, r, c, j;
char *board = snewn(len + 1, char);
assert(board);
memset(board, ' ', len);
for (r = 0; r < h; ++r) {
for (c = 0; c < w; ++c) {
int i = r*w + c, cell = r*ch*gw + c*cw;
board[cell] = "+BW"[(unsigned char)state->shared->clues[i]];
if (c < w - 1 && (state->lines[i] & R || state->lines[i+1] & L))
memset(board + cell + 1, '-', cw - 1);
if (r < h - 1 && (state->lines[i] & D || state->lines[i+w] & U))
for (j = 1; j < ch; ++j) board[cell + j*gw] = '|';
if (c < w - 1 && (state->marks[i] & R || state->marks[i+1] & L))
board[cell + cw/2] = 'x';
if (r < h - 1 && (state->marks[i] & D || state->marks[i+w] & U))
board[cell + (ch/2 * gw)] = 'x';
}
for (j = 0; j < (r == h - 1 ? 1 : ch); ++j)
board[r*ch*gw + (gw - 1) + j*gw] = '\n';
}
board[len] = '\0';
return board;
}
struct game_ui {
int *dragcoords; /* list of (y*w+x) coords in drag so far */
int ndragcoords; /* number of entries in dragcoords.
* 0 = click but no drag yet. -1 = no drag at all */
int clickx, clicky; /* pixel position of initial click */
int curx, cury; /* grid position of keyboard cursor */
bool cursor_active; /* true iff cursor is shown */
/*
* User preference: general visual style of the GUI. GUI_MASYU is
* how this puzzle is traditionally presented, with clue dots in
* the middle of grid squares, and the solution loop connecting
* square-centres. GUI_LOOPY shifts the grid by half a square in
* each direction, so that the clue dots are at _vertices_ of the
* grid and the solution loop follows the grid edges, which you
* could argue is more logical.
*/
enum { GUI_MASYU, GUI_LOOPY } gui_style;
};
static void legacy_prefs_override(struct game_ui *ui_out)
{
static bool initialised = false;
static int gui_style = -1;
if (!initialised) {
initialised = true;
switch (getenv_bool("PEARL_GUI_LOOPY", -1)) {
case 0:
gui_style = GUI_MASYU;
break;
case 1:
gui_style = GUI_LOOPY;
break;
}
}
if (gui_style != -1)
ui_out->gui_style = gui_style;
}
static game_ui *new_ui(const game_state *state)
{
game_ui *ui = snew(game_ui);
ui->ndragcoords = -1;
ui->dragcoords = state ? snewn(state->shared->sz, int) : NULL;
ui->cursor_active = getenv_bool("PUZZLES_SHOW_CURSOR", false);
ui->curx = ui->cury = 0;
ui->gui_style = GUI_MASYU;
legacy_prefs_override(ui);
return ui;
}
static void free_ui(game_ui *ui)
{
sfree(ui->dragcoords);
sfree(ui);
}
static config_item *get_prefs(game_ui *ui)
{
config_item *ret;
ret = snewn(2, config_item);
ret[0].name = "Puzzle appearance";
ret[0].kw = "appearance";
ret[0].type = C_CHOICES;
ret[0].u.choices.choicenames = ":Traditional:Loopy-style";
ret[0].u.choices.choicekws = ":traditional:loopy";
ret[0].u.choices.selected = ui->gui_style;
ret[1].name = NULL;
ret[1].type = C_END;
return ret;
}
static void set_prefs(game_ui *ui, const config_item *cfg)
{
ui->gui_style = cfg[0].u.choices.selected;
}
static void game_changed_state(game_ui *ui, const game_state *oldstate,
const game_state *newstate)
{
}
static const char *current_key_label(const game_ui *ui,
const game_state *state, int button)
{
if (IS_CURSOR_SELECT(button) && ui->cursor_active) {
if (button == CURSOR_SELECT) {
if (ui->ndragcoords == -1) return "Start";
return "Stop";
}
if (button == CURSOR_SELECT2 && ui->ndragcoords >= 0)
return "Cancel";
}
return "";
}
#define PREFERRED_TILE_SIZE 31
#define HALFSZ (ds->halfsz)
#define TILE_SIZE (ds->halfsz*2 + 1)
#define BORDER ((ui->gui_style == GUI_LOOPY) ? (TILE_SIZE/8) : (TILE_SIZE/2))
#define BORDER_WIDTH (max(TILE_SIZE / 32, 1))
#define COORD(x) ( (x) * TILE_SIZE + BORDER )
#define CENTERED_COORD(x) ( COORD(x) + TILE_SIZE/2 )
#define FROMCOORD(x) ( ((x) < BORDER) ? -1 : ( ((x) - BORDER) / TILE_SIZE) )
#define DS_ESHIFT 4 /* R/U/L/D shift, for error flags */
#define DS_DSHIFT 8 /* R/U/L/D shift, for drag-in-progress flags */
#define DS_MSHIFT 12 /* shift for no-line mark */
#define DS_ERROR_CLUE (1 << 20)
#define DS_FLASH (1 << 21)
#define DS_CURSOR (1 << 22)
struct game_drawstate {
int halfsz;
bool started;
int w, h, sz;
unsigned int *lflags; /* size w*h */
char *draglines; /* size w*h; lines flipped by current drag */
};
/*
* Routine shared between multiple callers to work out the intended
* effect of a drag path on the grid.
*
* Call it in a loop, like this:
*
* bool clearing = true;
* for (i = 0; i < ui->ndragcoords - 1; i++) {
* int sx, sy, dx, dy, dir, oldstate, newstate;
* interpret_ui_drag(state, ui, &clearing, i, &sx, &sy, &dx, &dy,
* &dir, &oldstate, &newstate);
*
* [do whatever is needed to handle the fact that the drag
* wants the edge from sx,sy to dx,dy (heading in direction
* 'dir' at the sx,sy end) to be changed from state oldstate
* to state newstate, each of which equals either 0 or dir]
* }
*/
static void interpret_ui_drag(const game_state *state, const game_ui *ui,
bool *clearing, int i, int *sx, int *sy,
int *dx, int *dy, int *dir,
int *oldstate, int *newstate)
{
int w = state->shared->w;
int sp = ui->dragcoords[i], dp = ui->dragcoords[i+1];
*sy = sp/w;
*sx = sp%w;
*dy = dp/w;
*dx = dp%w;
*dir = (*dy>*sy ? D : *dy<*sy ? U : *dx>*sx ? R : L);
*oldstate = state->lines[sp] & *dir;
if (*oldstate) {
/*
* The edge we've dragged over was previously
* present. Set it to absent, unless we've already
* stopped doing that.
*/
*newstate = *clearing ? 0 : *dir;
} else {
/*
* The edge we've dragged over was previously
* absent. Set it to present, and cancel the
* 'clearing' flag so that all subsequent edges in
* the drag are set rather than cleared.
*/
*newstate = *dir;
*clearing = false;
}
}
static void update_ui_drag(const game_state *state, game_ui *ui,
int gx, int gy)
{
int /* sz = state->shared->sz, */ w = state->shared->w;
int i, ox, oy, pos;
int lastpos;
if (!INGRID(state, gx, gy))
return; /* square is outside grid */
if (ui->ndragcoords < 0)
return; /* drag not in progress anyway */
pos = gy * w + gx;
lastpos = ui->dragcoords[ui->ndragcoords > 0 ? ui->ndragcoords-1 : 0];
if (pos == lastpos)
return; /* same square as last visited one */
/* Drag confirmed, if it wasn't already. */
if (ui->ndragcoords == 0)
ui->ndragcoords = 1;
/*
* Dragging the mouse into a square that's already been visited by
* the drag path so far has the effect of truncating the path back
* to that square, so a player can back out part of an uncommitted
* drag without having to let go of the mouse.
*
* An exception is that you're allowed to drag round in a loop
* back to the very start of the drag, provided that doesn't
* create a vertex of the wrong degree. This allows a player who's
* after an extra challenge to draw the entire loop in a single
* drag, without it cancelling itself just before release.
*/
for (i = 1; i < ui->ndragcoords; i++)
if (pos == ui->dragcoords[i]) {
ui->ndragcoords = i+1;
return;
}
if (pos == ui->dragcoords[0]) {
/* More complex check for a loop-shaped drag, which has to go
* through interpret_ui_drag to decide on the final degree of
* the start/end vertex. */
ui->dragcoords[ui->ndragcoords] = pos;
bool clearing = true;
int lines = state->lines[pos] & (L|R|U|D);
for (i = 0; i < ui->ndragcoords; i++) {
int sx, sy, dx, dy, dir, oldstate, newstate;
interpret_ui_drag(state, ui, &clearing, i, &sx, &sy, &dx, &dy,
&dir, &oldstate, &newstate);
if (sx == gx && sy == gy)
lines ^= (oldstate ^ newstate);
if (dx == gx && dy == gy)
lines ^= (F(oldstate) ^ F(newstate));
}
if (NBITS(lines) > 2) {
/* Bad vertex degree: fall back to the backtracking behaviour. */
ui->ndragcoords = 1;
return;
}
}
/*
* Otherwise, dragging the mouse into a square that's a rook-move
* away from the last one on the path extends the path.
*/
oy = ui->dragcoords[ui->ndragcoords-1] / w;
ox = ui->dragcoords[ui->ndragcoords-1] % w;
if (ox == gx || oy == gy) {
int dx = (gx < ox ? -1 : gx > ox ? +1 : 0);
int dy = (gy < oy ? -1 : gy > oy ? +1 : 0);
int dir = (dy>0 ? D : dy<0 ? U : dx>0 ? R : L);
while (ox != gx || oy != gy) {
/*
* If the drag attempts to cross a 'no line here' mark,
* stop there. We physically don't allow the user to drag
* over those marks.
*/
if (state->marks[oy*w+ox] & dir)
break;
ox += dx;
oy += dy;
ui->dragcoords[ui->ndragcoords++] = oy * w + ox;
}
}
/*
* Failing that, we do nothing at all: if the user has dragged
* diagonally across the board, they'll just have to return the
* mouse to the last known position and do whatever they meant to
* do again, more slowly and clearly.
*/
}
static char *mark_in_direction(const game_state *state, int x, int y, int dir,
bool primary, char *buf)
{
int w = state->shared->w /*, h = state->shared->h, sz = state->shared->sz */;
int x2 = x + DX(dir);
int y2 = y + DY(dir);
int dir2 = F(dir);
char ch = primary ? 'F' : 'M', *other;
if (!INGRID(state, x, y) || !INGRID(state, x2, y2)) return MOVE_UI_UPDATE;
/* disallow laying a mark over a line, or vice versa. */
other = primary ? state->marks : state->lines;
if (other[y*w+x] & dir || other[y2*w+x2] & dir2) return MOVE_UI_UPDATE;
sprintf(buf, "%c%d,%d,%d;%c%d,%d,%d", ch, dir, x, y, ch, dir2, x2, y2);
return dupstr(buf);
}
#define KEY_DIRECTION(btn) (\
(btn) == CURSOR_DOWN ? D : (btn) == CURSOR_UP ? U :\
(btn) == CURSOR_LEFT ? L : R)
static char *interpret_move(const game_state *state, game_ui *ui,
const game_drawstate *ds,
int x, int y, int button)
{
int w = state->shared->w, h = state->shared->h /*, sz = state->shared->sz */;
int gx = FROMCOORD(x), gy = FROMCOORD(y), i;
bool release = false;
char tmpbuf[80];
bool shift = button & MOD_SHFT, control = button & MOD_CTRL;
button &= ~MOD_MASK;
if (IS_MOUSE_DOWN(button)) {
ui->cursor_active = false;
if (!INGRID(state, gx, gy)) {
ui->ndragcoords = -1;
return MOVE_UI_UPDATE;
}
ui->clickx = x; ui->clicky = y;
ui->dragcoords[0] = gy * w + gx;
ui->ndragcoords = 0; /* will be 1 once drag is confirmed */
return MOVE_UI_UPDATE;
}
if (button == LEFT_DRAG && ui->ndragcoords >= 0) {
update_ui_drag(state, ui, gx, gy);
return MOVE_UI_UPDATE;
}
if (IS_MOUSE_RELEASE(button)) release = true;
if (IS_CURSOR_MOVE(button)) {
if (!ui->cursor_active) {
ui->cursor_active = true;
} else if (control || shift) {
char *move;
if (ui->ndragcoords > 0) return MOVE_NO_EFFECT;
ui->ndragcoords = -1;
move = mark_in_direction(state, ui->curx, ui->cury,
KEY_DIRECTION(button), control, tmpbuf);
if (control && !shift && *move)
move_cursor(button, &ui->curx, &ui->cury, w, h, false, NULL);
return move;
} else {
move_cursor(button, &ui->curx, &ui->cury, w, h, false, NULL);
if (ui->ndragcoords >= 0)
update_ui_drag(state, ui, ui->curx, ui->cury);
}
return MOVE_UI_UPDATE;
}
if (IS_CURSOR_SELECT(button)) {
if (!ui->cursor_active) {
ui->cursor_active = true;
return MOVE_UI_UPDATE;
} else if (button == CURSOR_SELECT) {
if (ui->ndragcoords == -1) {
ui->ndragcoords = 0;
ui->dragcoords[0] = ui->cury * w + ui->curx;
ui->clickx = CENTERED_COORD(ui->curx);
ui->clicky = CENTERED_COORD(ui->cury);
return MOVE_UI_UPDATE;
} else release = true;
} else if (button == CURSOR_SELECT2) {
if (ui->ndragcoords >= 0) {
ui->ndragcoords = -1;
return MOVE_UI_UPDATE;
}
return MOVE_NO_EFFECT;
}
}
if (button == 27 || button == '\b') {
if (ui->ndragcoords >= 0) {
ui->ndragcoords = -1;
return MOVE_UI_UPDATE;
}
return MOVE_NO_EFFECT;
}
if (release) {
if (ui->ndragcoords > 0) {
/* End of a drag: process the cached line data. */
int buflen = 0, bufsize = 256, tmplen;
char *buf = NULL;
const char *sep = "";
bool clearing = true;
for (i = 0; i < ui->ndragcoords - 1; i++) {
int sx, sy, dx, dy, dir, oldstate, newstate;
interpret_ui_drag(state, ui, &clearing, i, &sx, &sy, &dx, &dy,
&dir, &oldstate, &newstate);
if (oldstate != newstate) {
if (!buf) buf = snewn(bufsize, char);
tmplen = sprintf(tmpbuf, "%sF%d,%d,%d;F%d,%d,%d", sep,
dir, sx, sy, F(dir), dx, dy);
if (buflen + tmplen >= bufsize) {
bufsize = (buflen + tmplen) * 5 / 4 + 256;
buf = sresize(buf, bufsize, char);
}
strcpy(buf + buflen, tmpbuf);
buflen += tmplen;
sep = ";";
}
}
ui->ndragcoords = -1;
return buf ? buf : MOVE_UI_UPDATE;
} else if (ui->ndragcoords == 0) {
/* Click (or tiny drag). Work out which edge we were
* closest to. */
int cx, cy;
ui->ndragcoords = -1;
/*
* We process clicks based on the mouse-down location,
* because that's more natural for a user to carefully
* control than the mouse-up.
*/
x = ui->clickx;
y = ui->clicky;
gx = FROMCOORD(x);
gy = FROMCOORD(y);
cx = CENTERED_COORD(gx);
cy = CENTERED_COORD(gy);
if (!INGRID(state, gx, gy)) return MOVE_UI_UPDATE;
if (max(abs(x-cx),abs(y-cy)) < TILE_SIZE/4) {
/* TODO closer to centre of grid: process as a cell click not an edge click. */
return MOVE_UI_UPDATE;
} else {
int direction;
if (abs(x-cx) < abs(y-cy)) {
/* Closest to top/bottom edge. */
direction = (y < cy) ? U : D;
} else {
/* Closest to left/right edge. */
direction = (x < cx) ? L : R;
}
return mark_in_direction(state, gx, gy, direction,
(button == LEFT_RELEASE), tmpbuf);
}
}
}
if (button == 'H' || button == 'h')
return dupstr("H");
return MOVE_UNUSED;
}
static game_state *execute_move(const game_state *state, const char *move)
{
int w = state->shared->w, h = state->shared->h;
char c;
int x, y, l, n;
game_state *ret = dup_game(state);
debug(("move: %s\n", move));
while (*move) {
c = *move;
if (c == 'S') {
ret->used_solve = true;
move++;
} else if (c == 'L' || c == 'N' || c == 'R' || c == 'F' || c == 'M') {
/* 'line' or 'noline' or 'replace' or 'flip' or 'mark' */
move++;
if (sscanf(move, "%d,%d,%d%n", &l, &x, &y, &n) != 3)
goto badmove;
if (!INGRID(state, x, y)) goto badmove;
if (l < 0 || l > 15) goto badmove;
if (c == 'L')
ret->lines[y*w + x] |= (char)l;
else if (c == 'N')
ret->lines[y*w + x] &= ~((char)l);
else if (c == 'R') {
ret->lines[y*w + x] = (char)l;
ret->marks[y*w + x] &= ~((char)l); /* erase marks too */
} else if (c == 'F')
ret->lines[y*w + x] ^= (char)l;
else if (c == 'M')
ret->marks[y*w + x] ^= (char)l;
/*
* If we ended up trying to lay a line _over_ a mark,
* that's a failed move: interpret_move() should have
* ensured we never received a move string like that in
* the first place.
*/
if ((ret->lines[y*w + x] & (char)l) &&
(ret->marks[y*w + x] & (char)l))
goto badmove;
move += n;
} else if (strcmp(move, "H") == 0) {
pearl_solve(ret->shared->w, ret->shared->h,
ret->shared->clues, ret->lines, DIFFCOUNT, true);
for (n = 0; n < w*h; n++)
ret->marks[n] &= ~ret->lines[n]; /* erase marks too */
move++;
} else {
goto badmove;
}
if (*move == ';')
move++;
else if (*move)
goto badmove;
}
if (!check_completion(ret, true)) goto badmove;
return ret;
badmove:
free_game(ret);
return NULL;
}
/* ----------------------------------------------------------------------
* Drawing routines.
*/
#define FLASH_TIME 0.5F
static void game_compute_size(const game_params *params, int tilesize,
const game_ui *ui, int *x, int *y)
{
/* Ick: fake up `ds->tilesize' for macro expansion purposes */
struct { int halfsz; } ads, *ds = &ads;
ads.halfsz = (tilesize-1)/2;
*x = (params->w) * TILE_SIZE + 2 * BORDER;
*y = (params->h) * TILE_SIZE + 2 * BORDER;
}
static void game_set_size(drawing *dr, game_drawstate *ds,
const game_params *params, int tilesize)
{
ds->halfsz = (tilesize-1)/2;
}
static float *game_colours(frontend *fe, int *ncolours)
{
float *ret = snewn(3 * NCOLOURS, float);
int i;
game_mkhighlight(fe, ret, COL_BACKGROUND, COL_HIGHLIGHT, COL_LOWLIGHT);
for (i = 0; i < 3; i++) {
ret[COL_BLACK * 3 + i] = 0.0F;
ret[COL_WHITE * 3 + i] = 1.0F;
ret[COL_GRID * 3 + i] = 0.4F;
}
ret[COL_ERROR * 3 + 0] = 1.0F;
ret[COL_ERROR * 3 + 1] = 0.0F;
ret[COL_ERROR * 3 + 2] = 0.0F;
ret[COL_DRAGON * 3 + 0] = 0.0F;
ret[COL_DRAGON * 3 + 1] = 0.0F;
ret[COL_DRAGON * 3 + 2] = 1.0F;
ret[COL_DRAGOFF * 3 + 0] = 0.8F;
ret[COL_DRAGOFF * 3 + 1] = 0.8F;
ret[COL_DRAGOFF * 3 + 2] = 1.0F;
ret[COL_FLASH * 3 + 0] = 1.0F;
ret[COL_FLASH * 3 + 1] = 1.0F;
ret[COL_FLASH * 3 + 2] = 1.0F;
*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->halfsz = 0;
ds->started = false;
ds->w = state->shared->w;
ds->h = state->shared->h;
ds->sz = state->shared->sz;
ds->lflags = snewn(ds->sz, unsigned int);
for (i = 0; i < ds->sz; i++)
ds->lflags[i] = 0;
ds->draglines = snewn(ds->sz, char);
return ds;
}
static void game_free_drawstate(drawing *dr, game_drawstate *ds)
{
sfree(ds->draglines);
sfree(ds->lflags);
sfree(ds);
}
static void draw_lines_specific(drawing *dr, game_drawstate *ds,
const game_ui *ui, int x, int y,
unsigned int lflags, unsigned int shift, int c)
{
int ox = COORD(x), oy = COORD(y);
int t2 = HALFSZ, t16 = HALFSZ/4;
int cx = ox + t2, cy = oy + t2;
int d;
/* Draw each of the four directions, where laid (or error, or drag, etc.) */
for (d = 1; d < 16; d *= 2) {
int xoff = t2 * DX(d), yoff = t2 * DY(d);
int xnudge = abs(t16 * DX(C(d))), ynudge = abs(t16 * DY(C(d)));
if ((lflags >> shift) & d) {
int lx = cx + ((xoff < 0) ? xoff : 0) - xnudge;
int ly = cy + ((yoff < 0) ? yoff : 0) - ynudge;
if (c == COL_DRAGOFF && !(lflags & d))
continue;
if (c == COL_DRAGON && (lflags & d))
continue;
draw_rect(dr, lx, ly,
abs(xoff)+2*xnudge+1,
abs(yoff)+2*ynudge+1, c);
/* end cap */
draw_rect(dr, cx - t16, cy - t16, 2*t16+1, 2*t16+1, c);
}
}
}
static void draw_square(drawing *dr, game_drawstate *ds, const game_ui *ui,
int x, int y, unsigned int lflags, char clue)
{
int ox = COORD(x), oy = COORD(y);
int t2 = HALFSZ, t16 = HALFSZ/4;
int cx = ox + t2, cy = oy + t2;
int d;
assert(dr);
/* Clip to the grid square. */
clip(dr, ox, oy, TILE_SIZE, TILE_SIZE);
/* Clear the square. */
draw_rect(dr, ox, oy, TILE_SIZE, TILE_SIZE,
(lflags & DS_CURSOR) ?
COL_CURSOR_BACKGROUND : COL_BACKGROUND);
if (ui->gui_style == GUI_LOOPY) {
/* Draw small dot, underneath any lines. */
draw_circle(dr, cx, cy, t16, COL_GRID, COL_GRID);
} else {
/* Draw outline of grid square */
draw_line(dr, ox, oy, COORD(x+1), oy, COL_GRID);
draw_line(dr, ox, oy, ox, COORD(y+1), COL_GRID);
}
/* Draw grid: either thin gridlines, or no-line marks.
* We draw these first because the thick laid lines should be on top. */
for (d = 1; d < 16; d *= 2) {
int xoff = t2 * DX(d), yoff = t2 * DY(d);
if ((x == 0 && d == L) ||
(y == 0 && d == U) ||
(x == ds->w-1 && d == R) ||
(y == ds->h-1 && d == D))
continue; /* no gridlines out to the border. */
if ((lflags >> DS_MSHIFT) & d) {
/* either a no-line mark ... */
int mx = cx + xoff, my = cy + yoff, msz = t16;
draw_line(dr, mx-msz, my-msz, mx+msz, my+msz, COL_BLACK);
draw_line(dr, mx-msz, my+msz, mx+msz, my-msz, COL_BLACK);
} else {
if (ui->gui_style == GUI_LOOPY) {
/* draw grid lines connecting centre of cells */
draw_line(dr, cx, cy, cx+xoff, cy+yoff, COL_GRID);
}
}
}
/* Draw each of the four directions, where laid (or error, or drag, etc.)
* Order is important here, specifically for the eventual colours of the
* exposed end caps. */
draw_lines_specific(dr, ds, ui, x, y, lflags, 0,
(lflags & DS_FLASH ? COL_FLASH : COL_BLACK));
draw_lines_specific(dr, ds, ui, x, y, lflags, DS_ESHIFT, COL_ERROR);
draw_lines_specific(dr, ds, ui, x, y, lflags, DS_DSHIFT, COL_DRAGOFF);
draw_lines_specific(dr, ds, ui, x, y, lflags, DS_DSHIFT, COL_DRAGON);
/* Draw a clue, if present */
if (clue != NOCLUE) {
int c = (lflags & DS_FLASH) ? COL_FLASH :
(clue == STRAIGHT) ? COL_WHITE : COL_BLACK;
if (lflags & DS_ERROR_CLUE) /* draw a bigger 'error' clue circle. */
draw_circle(dr, cx, cy, TILE_SIZE*3/8, COL_ERROR, COL_ERROR);
draw_circle(dr, cx, cy, TILE_SIZE/4, c, COL_BLACK);
}
unclip(dr);
draw_update(dr, ox, oy, TILE_SIZE, TILE_SIZE);
}
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 w = state->shared->w, h = state->shared->h, sz = state->shared->sz;
int x, y, flashing = 0;
bool force = false;
if (!ds->started) {
if (ui->gui_style == GUI_MASYU) {
/*
* 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;
force = true;
}
if (flashtime > 0 &&
(flashtime <= FLASH_TIME/3 ||
flashtime >= FLASH_TIME*2/3))
flashing = DS_FLASH;
memset(ds->draglines, 0, sz);
if (ui->ndragcoords > 0) {
int i;
bool clearing = true;
for (i = 0; i < ui->ndragcoords - 1; i++) {
int sx, sy, dx, dy, dir, oldstate, newstate;
interpret_ui_drag(state, ui, &clearing, i, &sx, &sy, &dx, &dy,
&dir, &oldstate, &newstate);
ds->draglines[sy*w+sx] ^= (oldstate ^ newstate);
ds->draglines[dy*w+dx] ^= (F(oldstate) ^ F(newstate));
}
}
for (x = 0; x < w; x++) {
for (y = 0; y < h; y++) {
unsigned int f = (unsigned int)state->lines[y*w+x];
unsigned int eline = (unsigned int)(state->errors[y*w+x] & (R|U|L|D));
f |= eline << DS_ESHIFT;
f |= ((unsigned int)ds->draglines[y*w+x]) << DS_DSHIFT;
f |= ((unsigned int)state->marks[y*w+x]) << DS_MSHIFT;
if (state->errors[y*w+x] & ERROR_CLUE)
f |= DS_ERROR_CLUE;
f |= flashing;
if (ui->cursor_active && x == ui->curx && y == ui->cury)
f |= DS_CURSOR;
if (f != ds->lflags[y*w+x] || force) {
ds->lflags[y*w+x] = f;
draw_square(dr, ds, ui, x, y, f, state->shared->clues[y*w+x]);
}
}
}
}
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)
{
if (!oldstate->completed && newstate->completed &&
!oldstate->used_solve && !newstate->used_solve)
return FLASH_TIME;
else
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->cursor_active) {
*x = COORD(ui->curx);
*y = COORD(ui->cury);
*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)
{
int w = state->shared->w, h = state->shared->h, x, y;
int black = print_mono_colour(dr, 0);
int white = print_mono_colour(dr, 1);
/* Ick: fake up `ds->tilesize' for macro expansion purposes */
game_drawstate *ds = game_new_drawstate(dr, state);
game_set_size(dr, ds, NULL, tilesize);
if (ui->gui_style == GUI_MASYU) {
/* Draw grid outlines (black). */
for (x = 0; x <= w; x++)
draw_line(dr, COORD(x), COORD(0), COORD(x), COORD(h), black);
for (y = 0; y <= h; y++)
draw_line(dr, COORD(0), COORD(y), COORD(w), COORD(y), black);
} else {
/* Draw small dots, and dotted lines connecting them. For
* added clarity, try to start and end the dotted lines a
* little way away from the dots. */
print_line_width(dr, TILE_SIZE / 40);
print_line_dotted(dr, true);
for (x = 0; x < w; x++) {
for (y = 0; y < h; y++) {
int cx = COORD(x) + HALFSZ, cy = COORD(y) + HALFSZ;
draw_circle(dr, cx, cy, tilesize/10, black, black);
if (x+1 < w)
draw_line(dr, cx+tilesize/5, cy,
cx+tilesize-tilesize/5, cy, black);
if (y+1 < h)
draw_line(dr, cx, cy+tilesize/5,
cx, cy+tilesize-tilesize/5, black);
}
}
print_line_dotted(dr, false);
}
for (x = 0; x < w; x++) {
for (y = 0; y < h; y++) {
int cx = COORD(x) + HALFSZ, cy = COORD(y) + HALFSZ;
int clue = state->shared->clues[y*w+x];
draw_lines_specific(dr, ds, ui, x, y,
state->lines[y*w+x], 0, black);
if (clue != NOCLUE) {
int c = (clue == CORNER) ? black : white;
draw_circle(dr, cx, cy, TILE_SIZE/4, c, black);
}
}
}
game_free_drawstate(dr, ds);
}
#ifdef COMBINED
#define thegame pearl
#endif
const struct game thegame = {
"Pearl", "games.pearl", "pearl",
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,
get_prefs, set_prefs,
new_ui,
free_ui,
NULL, /* encode_ui */
NULL, /* decode_ui */
NULL, /* 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 */
0, /* flags */
};
#ifdef STANDALONE_SOLVER
#include <time.h>
#include <stdarg.h>
static const char *quis = NULL;
static void usage(FILE *out) {
fprintf(out, "usage: %s <params>\n", quis);
}
static void pnum(int n, int ntot, const char *desc)
{
printf("%2.1f%% (%d) %s", (double)n*100.0 / (double)ntot, n, desc);
}
static void start_soak(game_params *p, random_state *rs, int nsecs)
{
time_t tt_start, tt_now, tt_last;
int n = 0, nsolved = 0, nimpossible = 0, ret;
char *grid, *clues;
tt_start = tt_last = time(NULL);
/* Currently this generates puzzles of any difficulty (trying to solve it
* on the maximum difficulty level and not checking it's not too easy). */
printf("Soak-testing a %dx%d grid (any difficulty)", p->w, p->h);
if (nsecs > 0) printf(" for %d seconds", nsecs);
printf(".\n");
p->nosolve = true;
grid = snewn(p->w*p->h, char);
clues = snewn(p->w*p->h, char);
while (1) {
n += new_clues(p, rs, clues, grid); /* should be 1, with nosolve */
ret = pearl_solve(p->w, p->h, clues, grid, DIFF_TRICKY, false);
if (ret <= 0) nimpossible++;
if (ret == 1) nsolved++;
tt_now = time(NULL);
if (tt_now > tt_last) {
tt_last = tt_now;
printf("%d total, %3.1f/s, ",
n, (double)n / ((double)tt_now - tt_start));
pnum(nsolved, n, "solved"); printf(", ");
printf("%3.1f/s", (double)nsolved / ((double)tt_now - tt_start));
if (nimpossible > 0)
pnum(nimpossible, n, "impossible");
printf("\n");
}
if (nsecs > 0 && (tt_now - tt_start) > nsecs) {
printf("\n");
break;
}
}
sfree(grid);
sfree(clues);
}
int main(int argc, char *argv[])
{
game_params *p = NULL;
random_state *rs = NULL;
time_t seed = time(NULL);
char *id = NULL;
const char *err;
setvbuf(stdout, NULL, _IONBF, 0);
quis = argv[0];
while (--argc > 0) {
char *p = (char*)(*++argv);
if (!strcmp(p, "-e") || !strcmp(p, "--seed")) {
seed = atoi(*++argv);
argc--;
} else if (*p == '-') {
fprintf(stderr, "%s: unrecognised option `%s'\n", argv[0], p);
usage(stderr);
exit(1);
} else {
id = p;
}
}
rs = random_new((void*)&seed, sizeof(time_t));
p = default_params();
if (id) {
if (strchr(id, ':')) {
fprintf(stderr, "soak takes params only.\n");
goto done;
}
decode_params(p, id);
err = validate_params(p, true);
if (err) {
fprintf(stderr, "%s: %s", argv[0], err);
goto done;
}
start_soak(p, rs, 0); /* run forever */
} else {
int i;
for (i = 5; i <= 12; i++) {
p->w = p->h = i;
start_soak(p, rs, 5);
}
}
done:
free_params(p);
random_free(rs);
return 0;
}
#endif
/* vim: set shiftwidth=4 tabstop=8: */