static Skyline conditional_skyline (Grob *, Grob *);
static Grob *extremal_break_aligned_grob (Grob *, Direction, Interval *);
static Real set_distance (Item *left, Item *right, Real padding);
static Skyline conditional_skyline (Grob *, Grob *);
static Grob *extremal_break_aligned_grob (Grob *, Direction, Interval *);
static Real set_distance (Item *left, Item *right, Real padding);