+static char get_dir_to_nearest_enemy(struct MapObj * mo_origin)
+{
+ char * f_name = "get_dir_to_nearest_enemy()";
+
+ /* Calculate for each cell the distance to the visibly nearest map actor not
+ * "mo_origin", with movement only possible in the directions of "dir".
+ * (Actors' own cells start with a distance of 0 towards themselves.)
+ */
+ uint32_t map_size = world.map.size.y * world.map.size.x;
+ uint16_t max_score = UINT16_MAX - 1;
+ uint16_t * score_map = try_malloc(map_size * sizeof(uint16_t), f_name);
+ uint8_t * fov_map = world.enemy_fov ? build_fov_map(mo_origin) : NULL;
+ uint32_t i;
+ for (i = 0; i < map_size; i++)
+ {
+ if (world.enemy_fov)
+ {
+ score_map[i] = fov_map[i] & VISIBLE ? max_score : UINT16_MAX;
+ }
+ else
+ {
+ score_map[i] = max_score;
+ }
+ }
+ free(fov_map);
+ struct MapObj * mo = world.map_objs;
+ for (; mo != NULL; mo = mo->next)
+ {
+ if (!mo->lifepoints || mo == mo_origin)
+ {
+ continue;
+ }
+ score_map[(mo->pos.y * world.map.size.x) + mo->pos.x] = 0;
+ }
+ dijkstra_map(score_map, max_score);
+
+ /* Return direction of "mo_origin"'s lowest-scored neighbor cell. */
+ uint16_t neighbors[N_DIRS];
+ uint16_t pos_i = (mo_origin->pos.y * world.map.size.x) + mo_origin->pos.x;
+ get_neighbor_scores(score_map, pos_i, max_score, neighbors);
+ free(score_map);
+ char dir_to_nearest_enemy = 0;
+ uint16_t min_neighbor = max_score;
+ char * dirs = "edcxsw"; /* get_neighbor_scores()'s clockwise dir order.*/
+ for (i = 0; i < N_DIRS; i++)
+ {
+ if (min_neighbor > neighbors[i])
+ {
+ min_neighbor = neighbors[i];
+ dir_to_nearest_enemy = dirs[i];
+ }
+ }
+ return dir_to_nearest_enemy;
+}
+
+
+
+extern void ai(struct MapObj * mo)