/*
  staff-sym-referencer.hh -- declare staff_symbol_referencer

  source file of the GNU LilyPond music typesetter

  (c) 1999--2007 Han-Wen Nienhuys <hanwen@xs4all.nl>
*/

#ifndef STAFF_SYMBOL_REFERENCER_HH
#define STAFF_SYMBOL_REFERENCER_HH

#include "grob-interface.hh"
#include "lily-proto.hh"

/**
   A notation object that needs access to variables of the staff (no
   lines, leading).
*/
class Staff_symbol_referencer
{
public:
  DECLARE_GROB_INTERFACE();
  static bool ugly_hack (Grob *);
  static void set_position (Grob *, Real);
  DECLARE_SCHEME_CALLBACK (callback, (SCM element));

  /**
     Leading are the lead strips between the sticks (lines) of
     typeface. ie. leading is vertical space.
  */
  static Real line_thickness (Grob *);
  static Real staff_space (Grob *);
  static Grob *get_staff_symbol (Grob *);
  static bool on_line (Grob *, int);
  static bool on_staff_line (Grob *, int);
  static int line_count (Grob *);
  static Real get_position (Grob *);
  static Real staff_radius (Grob *);
  static int get_rounded_position (Grob *);
  static Interval extent_in_staff (Grob *); 
};

int compare_position (Grob *const &, Grob *const &);\
bool position_less (Grob *const &, Grob *const &);
#endif /* STAFF_SYMBOL_REFERENCER_HH */

