+ /* vertical ordering */
+ static bool internal_vertical_less (Grob *g1, Grob *g2, bool pure);
+ static Grob *get_root_vertical_alignment (Grob *g);
+ static Grob *get_vertical_axis_group (Grob *g);
+ static bool vertical_less (Grob *g1, Grob *g2);
+ static bool pure_vertical_less (Grob *g1, Grob *g2);
+ static int get_vertical_axis_group_index (Grob *g);
+
+ /* skylines */
+ virtual Interval_t<int> spanned_rank_interval () const;
+ virtual bool pure_is_visible (int start, int end) const;
+ bool check_cross_staff (Grob *common);
+ static bool less (Grob *g1, Grob *g2);
+ static SCM internal_simple_skylines_from_stencil (SCM, Axis);
+ static SCM internal_skylines_from_element_stencils (SCM, Axis);