The Net solver now makes use of barrier information when applied to

a typed-in grid.

[originally from svn r5827]
This commit is contained in:
Simon Tatham
2005-05-22 11:15:03 +00:00
parent d45d94d355
commit fc3f16b364

32
net.c
View File

@ -415,7 +415,8 @@ static int todo_get(struct todo *todo) {
return ret;
}
static int net_solver(int w, int h, unsigned char *tiles, int wrapping)
static int net_solver(int w, int h, unsigned char *tiles,
unsigned char *barriers, int wrapping)
{
unsigned char *tilestate;
unsigned char *edgestate;
@ -522,6 +523,30 @@ static int net_solver(int w, int h, unsigned char *tiles, int wrapping)
}
}
/*
* If we have barriers available, we can mark those edges as
* closed too.
*/
if (barriers) {
for (y = 0; y < h; y++) for (x = 0; x < w; x++) {
int d;
for (d = 1; d <= 8; d += d) {
if (barriers[y*w+x] & d) {
int x2, y2;
/*
* In principle the barrier list should already
* contain each barrier from each side, but
* let's not take chances with our internal
* consistency.
*/
OFFSETWH(x2, y2, x, y, d, w, h);
edgestate[(y*w+x) * 5 + d] = 2;
edgestate[(y2*w+x2) * 5 + F(d)] = 2;
}
}
}
}
/*
* Since most deductions made by this solver are local (the
* exception is loop avoidance, where joining two tiles
@ -1264,7 +1289,7 @@ static char *new_game_desc(game_params *params, random_state *rs,
/*
* Run the solver to check unique solubility.
*/
while (!net_solver(w, h, tiles, params->wrapping)) {
while (!net_solver(w, h, tiles, NULL, params->wrapping)) {
int n = 0;
/*
@ -1641,7 +1666,8 @@ static game_state *solve_game(game_state *state, game_aux_info *aux,
* not yield a complete solution.
*/
ret = dup_game(state);
net_solver(ret->width, ret->height, ret->tiles, ret->wrapping);
net_solver(ret->width, ret->height, ret->tiles,
ret->barriers, ret->wrapping);
} else {
assert(aux->width == state->width);
assert(aux->height == state->height);