ref: 29eaa8f55c7b9cc960afa4327a7ce977e6637e9c
dir: /loopgen.h/
/* * loopgen.h: interface file for loop generation functions for grid.[ch]. */ #ifndef PUZZLES_LOOPGEN_H #define PUZZLES_LOOPGEN_H #include "puzzles.h" #include "grid.h" enum face_colour { FACE_WHITE, FACE_GREY, FACE_BLACK }; /* face should be of type grid_face* here. */ #define FACE_COLOUR(face) \ ( (face) == NULL ? FACE_BLACK : \ board[(face)->index] ) typedef int (*loopgen_bias_fn_t)(void *ctx, char *board, int face); /* 'board' should be a char array whose length is the same as * g->num_faces: this will be filled in with FACE_WHITE or FACE_BLACK * after loop generation. * * If 'bias' is non-null, it should be a user-provided function which * rates a half-finished board (i.e. may include some FACE_GREYs) for * desirability; this will cause the loop generator to bias in favour * of loops with a high return value from that function. The 'face' * parameter to the bias function indicates which face of the grid has * been modified since the last call; it is guaranteed that only one * will have been (so that bias functions can work incrementally * rather than re-scanning the whole grid on every call). */ extern void generate_loop(grid *g, char *board, random_state *rs, loopgen_bias_fn_t bias, void *biasctx); #endif