/*
* TODO:
*
- * - error highlighting
* - clue marking
* - more solver brains?
* - better four-colouring algorithm?
*/
#define DIFFLIST(A) \
A(EASY,Easy,e) \
- A(NORMAL,Normal,n)
+ A(NORMAL,Normal,n) \
+ A(RECURSE,Unreasonable,u)
#define ENUM(upper,title,lower) DIFF_ ## upper,
#define TITLE(upper,title,lower) #title,
#define ENCODE(upper,title,lower) #lower
COL_BACKGROUND,
COL_GRID,
COL_0, COL_1, COL_2, COL_3,
+ COL_ERROR, COL_ERRTEXT,
NCOLOURS
};
int n;
int ngraph;
int *immutable;
+ int *edgex, *edgey; /* positions of a point on each edge */
};
struct game_state {
return j;
}
-static int graph_adjacent(int *graph, int n, int ngraph, int i, int j)
+static int graph_edge_index(int *graph, int n, int ngraph, int i, int j)
{
int v = i*n+j;
int top, bot, mid;
while (top - bot > 1) {
mid = (top + bot) / 2;
if (graph[mid] == v)
- return TRUE;
+ return mid;
else if (graph[mid] < v)
bot = mid;
else
top = mid;
}
- return FALSE;
+ return -1;
}
+#define graph_adjacent(graph, n, ngraph, i, j) \
+ (graph_edge_index((graph), (n), (ngraph), (i), (j)) >= 0)
+
static int graph_vertex_start(int *graph, int n, int ngraph, int i)
{
int v = i*n;
int *graph;
int n;
int ngraph;
+ int depth;
};
static struct solver_scratch *new_scratch(int *graph, int n, int ngraph)
sc->n = n;
sc->ngraph = ngraph;
sc->possible = snewn(n, unsigned char);
+ sc->depth = 0;
return sc;
}
}
/*
- * We've run out of things to deduce. See if we've got the lot.
+ * See if we've got a complete solution, and return if so.
*/
for (i = 0; i < n; i++)
if (colouring[i] < 0)
- return 2;
+ break;
+ if (i == n)
+ return 1; /* success! */
+
+ /*
+ * If recursion is not permissible, we now give up.
+ */
+ if (difficulty < DIFF_RECURSE)
+ return 2; /* unable to complete */
+
+ /*
+ * Now we've got to do something recursive. So first hunt for a
+ * currently-most-constrained region.
+ */
+ {
+ int best, bestc;
+ struct solver_scratch *rsc;
+ int *subcolouring, *origcolouring;
+ int ret, subret;
+ int we_already_got_one;
+
+ best = -1;
+ bestc = FIVE;
+
+ for (i = 0; i < n; i++) if (colouring[i] < 0) {
+ int p = sc->possible[i];
+ enum { compile_time_assertion = 1 / (FOUR <= 4) };
+ int c;
+
+ /* Count the set bits. */
+ c = (p & 5) + ((p >> 1) & 5);
+ c = (c & 3) + ((c >> 2) & 3);
+ assert(c > 1); /* or colouring[i] would be >= 0 */
+
+ if (c < bestc) {
+ best = i;
+ bestc = c;
+ }
+ }
+
+ assert(best >= 0); /* or we'd be solved already */
+
+ /*
+ * Now iterate over the possible colours for this region.
+ */
+ rsc = new_scratch(graph, n, ngraph);
+ rsc->depth = sc->depth + 1;
+ origcolouring = snewn(n, int);
+ memcpy(origcolouring, colouring, n * sizeof(int));
+ subcolouring = snewn(n, int);
+ we_already_got_one = FALSE;
+ ret = 0;
+
+ for (i = 0; i < FOUR; i++) {
+ if (!(sc->possible[best] & (1 << i)))
+ continue;
+
+ memcpy(subcolouring, origcolouring, n * sizeof(int));
+ subcolouring[best] = i;
+ subret = map_solver(rsc, graph, n, ngraph,
+ subcolouring, difficulty);
+
+ /*
+ * If this possibility turned up more than one valid
+ * solution, or if it turned up one and we already had
+ * one, we're definitely ambiguous.
+ */
+ if (subret == 2 || (subret == 1 && we_already_got_one)) {
+ ret = 2;
+ break;
+ }
- return 1; /* success! */
+ /*
+ * If this possibility turned up one valid solution and
+ * it's the first we've seen, copy it into the output.
+ */
+ if (subret == 1) {
+ memcpy(colouring, subcolouring, n * sizeof(int));
+ we_already_got_one = TRUE;
+ ret = 1;
+ }
+
+ /*
+ * Otherwise, this guess led to a contradiction, so we
+ * do nothing.
+ */
+ }
+
+ sfree(subcolouring);
+ free_scratch(rsc);
+
+ return ret;
+ }
}
/* ----------------------------------------------------------------------
* Finally, check that the puzzle is _at least_ as hard as
* required, and indeed that it isn't already solved.
* (Calling map_solver with negative difficulty ensures the
- * latter - if a solver which _does nothing_ can't solve
- * it, it's too easy!)
+ * latter - if a solver which _does nothing_ can solve it,
+ * it's too easy!)
*/
memcpy(colouring2, colouring, n*sizeof(int));
if (map_solver(sc, graph, n, ngraph, colouring2,
/*
* Drop minimum difficulty if necessary.
*/
- if (mindiff > 0 && (n < 9 || n > 3*wh/2)) {
+ if (mindiff > 0 && (n < 9 || n > 2*wh/3)) {
if (tries-- <= 0)
mindiff = 0; /* give up and go for Easy */
}
random_free(rs);
}
+ /*
+ * Analyse the map to find a canonical line segment
+ * corresponding to each edge. These are where we'll eventually
+ * put error markers.
+ */
+ {
+ int *bestx, *besty, *an, pass;
+ float *ax, *ay, *best;
+
+ ax = snewn(state->map->ngraph, float);
+ ay = snewn(state->map->ngraph, float);
+ an = snewn(state->map->ngraph, int);
+ bestx = snewn(state->map->ngraph, int);
+ besty = snewn(state->map->ngraph, int);
+ best = snewn(state->map->ngraph, float);
+
+ for (i = 0; i < state->map->ngraph; i++) {
+ bestx[i] = besty[i] = -1;
+ best[i] = 2*(w+h)+1;
+ ax[i] = ay[i] = 0.0F;
+ an[i] = 0;
+ }
+
+ /*
+ * We make two passes over the map, finding all the line
+ * segments separating regions. In the first pass, we
+ * compute the _average_ x and y coordinate of all the line
+ * segments separating each pair of regions; in the second
+ * pass, for each such average point, we find the line
+ * segment closest to it and call that canonical.
+ *
+ * Line segments are considered to have coordinates in
+ * their centre. Thus, at least one coordinate for any line
+ * segment is always something-and-a-half; so we store our
+ * coordinates as twice their normal value.
+ */
+ for (pass = 0; pass < 2; pass++) {
+ int x, y;
+
+ for (y = 0; y < h; y++)
+ for (x = 0; x < w; x++) {
+ int ex[4], ey[4], ea[4], eb[4], en = 0;
+
+ /*
+ * Look for an edge to the right of this
+ * square, an edge below it, and an edge in the
+ * middle of it. Also look to see if the point
+ * at the bottom right of this square is on an
+ * edge (and isn't a place where more than two
+ * regions meet).
+ */
+ if (x+1 < w) {
+ /* right edge */
+ ea[en] = state->map->map[RE * wh + y*w+x];
+ eb[en] = state->map->map[LE * wh + y*w+(x+1)];
+ if (ea[en] != eb[en]) {
+ ex[en] = (x+1)*2;
+ ey[en] = y*2+1;
+ en++;
+ }
+ }
+ if (y+1 < h) {
+ /* bottom edge */
+ ea[en] = state->map->map[BE * wh + y*w+x];
+ eb[en] = state->map->map[TE * wh + (y+1)*w+x];
+ if (ea[en] != eb[en]) {
+ ex[en] = x*2+1;
+ ey[en] = (y+1)*2;
+ en++;
+ }
+ }
+ /* diagonal edge */
+ ea[en] = state->map->map[TE * wh + y*w+x];
+ eb[en] = state->map->map[BE * wh + y*w+x];
+ if (ea[en] != eb[en]) {
+ ex[en] = x*2+1;
+ ey[en] = y*2+1;
+ en++;
+ }
+ if (x+1 < w && y+1 < h) {
+ /* bottom right corner */
+ int oct[8], othercol, nchanges;
+ oct[0] = state->map->map[RE * wh + y*w+x];
+ oct[1] = state->map->map[LE * wh + y*w+(x+1)];
+ oct[2] = state->map->map[BE * wh + y*w+(x+1)];
+ oct[3] = state->map->map[TE * wh + (y+1)*w+(x+1)];
+ oct[4] = state->map->map[LE * wh + (y+1)*w+(x+1)];
+ oct[5] = state->map->map[RE * wh + (y+1)*w+x];
+ oct[6] = state->map->map[TE * wh + (y+1)*w+x];
+ oct[7] = state->map->map[BE * wh + y*w+x];
+
+ othercol = -1;
+ nchanges = 0;
+ for (i = 0; i < 8; i++) {
+ if (oct[i] != oct[0]) {
+ if (othercol < 0)
+ othercol = oct[i];
+ else if (othercol != oct[i])
+ break; /* three colours at this point */
+ }
+ if (oct[i] != oct[(i+1) & 7])
+ nchanges++;
+ }
+
+ /*
+ * Now if there are exactly two regions at
+ * this point (not one, and not three or
+ * more), and only two changes around the
+ * loop, then this is a valid place to put
+ * an error marker.
+ */
+ if (i == 8 && othercol >= 0 && nchanges == 2) {
+ ea[en] = oct[0];
+ eb[en] = othercol;
+ ex[en] = (x+1)*2;
+ ey[en] = (y+1)*2;
+ en++;
+ }
+ }
+
+ /*
+ * Now process the edges we've found, one by
+ * one.
+ */
+ for (i = 0; i < en; i++) {
+ int emin = min(ea[i], eb[i]);
+ int emax = max(ea[i], eb[i]);
+ int gindex =
+ graph_edge_index(state->map->graph, n,
+ state->map->ngraph, emin, emax);
+
+ assert(gindex >= 0);
+
+ if (pass == 0) {
+ /*
+ * In pass 0, accumulate the values
+ * we'll use to compute the average
+ * positions.
+ */
+ ax[gindex] += ex[i];
+ ay[gindex] += ey[i];
+ an[gindex] += 1.0F;
+ } else {
+ /*
+ * In pass 1, work out whether this
+ * point is closer to the average than
+ * the last one we've seen.
+ */
+ float dx, dy, d;
+
+ assert(an[gindex] > 0);
+ dx = ex[i] - ax[gindex];
+ dy = ey[i] - ay[gindex];
+ d = sqrt(dx*dx + dy*dy);
+ if (d < best[gindex]) {
+ best[gindex] = d;
+ bestx[gindex] = ex[i];
+ besty[gindex] = ey[i];
+ }
+ }
+ }
+ }
+
+ if (pass == 0) {
+ for (i = 0; i < state->map->ngraph; i++)
+ if (an[i] > 0) {
+ ax[i] /= an[i];
+ ay[i] /= an[i];
+ }
+ }
+ }
+
+ state->map->edgex = bestx;
+ state->map->edgey = besty;
+
+ for (i = 0; i < state->map->ngraph; i++)
+ if (state->map->edgex[i] < 0) {
+ /* Find the other representation of this edge. */
+ int e = state->map->graph[i];
+ int iprime = graph_edge_index(state->map->graph, n,
+ state->map->ngraph, e%n, e/n);
+ assert(state->map->edgex[iprime] >= 0);
+ state->map->edgex[i] = state->map->edgex[iprime];
+ state->map->edgey[i] = state->map->edgey[iprime];
+ }
+
+ sfree(ax);
+ sfree(ay);
+ sfree(an);
+ sfree(best);
+ }
+
return state;
}
sfree(state->map->map);
sfree(state->map->graph);
sfree(state->map->immutable);
+ sfree(state->map->edgex);
+ sfree(state->map->edgey);
sfree(state->map);
}
sfree(state->colouring);
return NULL;
}
- retlen = retsize = 0;
- ret = NULL;
+ retsize = 64;
+ ret = snewn(retsize, char);
+ strcpy(ret, "S");
+ retlen = 1;
for (i = 0; i < state->map->n; i++) {
int len;
continue;
assert(!state->map->immutable[i]);
- len = sprintf(buf, "%s%d:%d", retlen ? ";" : "S;",
- colouring[i], i);
+ len = sprintf(buf, ";%d:%d", colouring[i], i);
if (retlen + len >= retsize) {
retsize = retlen + len + 256;
ret = sresize(ret, retsize, char);
struct game_drawstate {
int tilesize;
- unsigned char *drawn;
+ unsigned short *drawn, *todraw;
int started;
int dragx, dragy, drag_visible;
blitter *bl;
};
+/* Flags in `drawn'. */
+#define ERR_BASE 0x0080
+#define ERR_MASK 0xFF80
+
#define TILESIZE (ds->tilesize)
#define BORDER (TILESIZE)
#define COORD(x) ( (x) * TILESIZE + BORDER )
memcpy(ret + COL_2 * 3, map_colours[2], 3 * sizeof(float));
memcpy(ret + COL_3 * 3, map_colours[3], 3 * sizeof(float));
+ ret[COL_ERROR * 3 + 0] = 1.0F;
+ ret[COL_ERROR * 3 + 1] = 0.0F;
+ ret[COL_ERROR * 3 + 2] = 0.0F;
+
+ ret[COL_ERRTEXT * 3 + 0] = 1.0F;
+ ret[COL_ERRTEXT * 3 + 1] = 1.0F;
+ ret[COL_ERRTEXT * 3 + 2] = 1.0F;
+
*ncolours = NCOLOURS;
return ret;
}
static game_drawstate *game_new_drawstate(drawing *dr, game_state *state)
{
struct game_drawstate *ds = snew(struct game_drawstate);
+ int i;
ds->tilesize = 0;
- ds->drawn = snewn(state->p.w * state->p.h, unsigned char);
- memset(ds->drawn, 0xFF, state->p.w * state->p.h);
+ ds->drawn = snewn(state->p.w * state->p.h, unsigned short);
+ for (i = 0; i < state->p.w * state->p.h; i++)
+ ds->drawn[i] = 0xFFFF;
+ ds->todraw = snewn(state->p.w * state->p.h, unsigned short);
ds->started = FALSE;
ds->bl = NULL;
ds->drag_visible = FALSE;
static void game_free_drawstate(drawing *dr, game_drawstate *ds)
{
sfree(ds->drawn);
+ sfree(ds->todraw);
if (ds->bl)
blitter_free(dr, ds->bl);
sfree(ds);
}
+static void draw_error(drawing *dr, game_drawstate *ds, int x, int y)
+{
+ int coords[8];
+ int yext, xext;
+
+ /*
+ * Draw a diamond.
+ */
+ coords[0] = x - TILESIZE*2/5;
+ coords[1] = y;
+ coords[2] = x;
+ coords[3] = y - TILESIZE*2/5;
+ coords[4] = x + TILESIZE*2/5;
+ coords[5] = y;
+ coords[6] = x;
+ coords[7] = y + TILESIZE*2/5;
+ draw_polygon(dr, coords, 4, COL_ERROR, COL_GRID);
+
+ /*
+ * Draw an exclamation mark in the diamond. This turns out to
+ * look unpleasantly off-centre if done via draw_text, so I do
+ * it by hand on the basis that exclamation marks aren't that
+ * difficult to draw...
+ */
+ xext = TILESIZE/16;
+ yext = TILESIZE*2/5 - (xext*2+2);
+ draw_rect(dr, x-xext, y-yext, xext*2+1, yext*2+1 - (xext*3),
+ COL_ERRTEXT);
+ draw_rect(dr, x-xext, y+yext-xext*2+1, xext*2+1, xext*2, COL_ERRTEXT);
+}
+
static void draw_square(drawing *dr, game_drawstate *ds,
game_params *params, struct map *map,
int x, int y, int v)
{
int w = params->w, h = params->h, wh = w*h;
- int tv = v / FIVE, bv = v % FIVE;
+ int tv, bv, xo, yo, errs;
+
+ errs = v & ERR_MASK;
+ v &= ~ERR_MASK;
+ tv = v / FIVE;
+ bv = v % FIVE;
clip(dr, COORD(x), COORD(y), TILESIZE, TILESIZE);
map->map[BE*wh+(y-1)*w+(x-1)] != map->map[LE*wh+y*w+x])
draw_rect(dr, COORD(x), COORD(y), 1, 1, COL_GRID);
+ /*
+ * Draw error markers.
+ */
+ for (yo = 0; yo < 3; yo++)
+ for (xo = 0; xo < 3; xo++)
+ if (errs & (ERR_BASE << (yo*3+xo)))
+ draw_error(dr, ds,
+ (COORD(x)*2+TILESIZE*xo)/2,
+ (COORD(y)*2+TILESIZE*yo)/2);
+
unclip(dr);
+
draw_update(dr, COORD(x), COORD(y), TILESIZE, TILESIZE);
}
game_state *state, int dir, game_ui *ui,
float animtime, float flashtime)
{
- int w = state->p.w, h = state->p.h, wh = w*h /*, n = state->p.n */;
- int x, y;
+ int w = state->p.w, h = state->p.h, wh = w*h, n = state->p.n;
+ int x, y, i;
int flash;
if (ds->drag_visible) {
} else
flash = -1;
+ /*
+ * Set up the `todraw' array.
+ */
for (y = 0; y < h; y++)
for (x = 0; x < w; x++) {
int tv = state->colouring[state->map->map[TE * wh + y*w+x]];
v = tv * FIVE + bv;
+ ds->todraw[y*w+x] = v;
+ }
+
+ /*
+ * Add error markers to the `todraw' array.
+ */
+ for (i = 0; i < state->map->ngraph; i++) {
+ int v1 = state->map->graph[i] / n;
+ int v2 = state->map->graph[i] % n;
+ int xo, yo;
+
+ if (state->colouring[v1] < 0 || state->colouring[v2] < 0)
+ continue;
+ if (state->colouring[v1] != state->colouring[v2])
+ continue;
+
+ x = state->map->edgex[i];
+ y = state->map->edgey[i];
+
+ xo = x % 2; x /= 2;
+ yo = y % 2; y /= 2;
+
+ ds->todraw[y*w+x] |= ERR_BASE << (yo*3+xo);
+ if (xo == 0) {
+ assert(x > 0);
+ ds->todraw[y*w+(x-1)] |= ERR_BASE << (yo*3+2);
+ }
+ if (yo == 0) {
+ assert(y > 0);
+ ds->todraw[(y-1)*w+x] |= ERR_BASE << (2*3+xo);
+ }
+ if (xo == 0 && yo == 0) {
+ assert(x > 0 && y > 0);
+ ds->todraw[(y-1)*w+(x-1)] |= ERR_BASE << (2*3+2);
+ }
+ }
+
+ /*
+ * Now actually draw everything.
+ */
+ for (y = 0; y < h; y++)
+ for (x = 0; x < w; x++) {
+ int v = ds->todraw[y*w+x];
if (ds->drawn[y*w+x] != v) {
draw_square(dr, ds, &state->p, state->map, x, y, v);
ds->drawn[y*w+x] = v;
~mdw / sgt / puzzles / blobdiff