/* db.c */
int get_height(const struct field_info *, const char *, dbDriver *, int,
               double *);

/* extrude.c */
int extrude(struct Map_info *, struct Map_info *, const struct line_cats *,
            const struct line_pnts *, int, int, int, double, int, double,
            double, double, const struct Cell_head *, int, int);
