lily/include/pitch.hh

   1 /*
   2   pitch.hh -- declare Pitch
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1998--2007 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7 */
   8
   9 #ifndef MUSICAL_PITCH_HH
  10 #define MUSICAL_PITCH_HH
  11
  12 #include "lily-proto.hh"
  13 #include "smobs.hh"
  14 #include "rational.hh"
  15
  16
  17 /** A "tonal" pitch. This is a pitch used in diatonal western music
  18     (24 quartertones in an octave), as opposed to a frequency in Hz or a
  19     integer number of semitones.
  20
  21     Pitch is lexicographically ordered by (octave, notename,
  22     alteration).
  23
  24 */
  25 class Pitch
  26 {
  27 private:
  28   int octave_;
  29   int notename_;
  30   Rational alteration_;
  31   Scale *scale_;
  32
  33   void transpose (Pitch);
  34   void up_to (int);
  35   void down_to (int);
  36   void normalize_octave ();
  37   void normalize_alteration ();
  38   void normalize ();
  39
  40 public:
  41   int get_octave () const;
  42   int get_notename () const;
  43   Rational get_alteration () const;
  44
  45   Pitch (int octave, int notename, Rational accidental);
  46   Pitch (int octave, int notename);
  47   Pitch ();
  48
  49   Pitch transposed (Pitch) const;
  50   Pitch to_relative_octave (Pitch) const;
  51
  52   static int compare (Pitch const &, Pitch const &);
  53
  54   int steps () const;
  55   Rational tone_pitch () const;
  56   int rounded_semitone_pitch () const;
  57   int rounded_quartertone_pitch () const;
  58   Pitch negated () const;
  59   string to_string () const;
  60
  61   DECLARE_SCHEME_CALLBACK (less_p, (SCM a, SCM b));
  62   DECLARE_SIMPLE_SMOBS (Pitch);
  63 };
  64
  65
  66 enum {
  67   DOUBLE_FLAT = -4,
  68   THREE_Q_FLAT,
  69   FLAT,
  70   SEMI_FLAT,
  71   NATURAL,
  72   SEMI_SHARP,
  73   SHARP,
  74   THREE_Q_SHARP,
  75   DOUBLE_SHARP,
  76 };
  77
  78 extern Rational  DOUBLE_FLAT_ALTERATION;
  79 extern Rational  THREE_Q_FLAT_ALTERATION;
  80 extern Rational  FLAT_ALTERATION;
  81 extern Rational  SEMI_FLAT_ALTERATION;
  82 extern Rational  NATURAL_ALTERATION;
  83 extern Rational  SEMI_SHARP_ALTERATION;
  84 extern Rational  SHARP_ALTERATION;
  85 extern Rational  THREE_Q_SHARP_ALTERATION;
  86 extern Rational  DOUBLE_SHARP_ALTERATION;
  87
  88 SCM ly_pitch_diff (SCM pitch, SCM root);
  89 SCM ly_pitch_transpose (SCM p, SCM delta);
  90 DECLARE_UNSMOB (Pitch, pitch);
  91
  92 INSTANTIATE_COMPARE (Pitch, Pitch::compare);
  93
  94 extern SCM pitch_less_proc;
  95 Pitch pitch_interval (Pitch const &from, Pitch const &to);
  96
  97 #endif /* MUSICAL_PITCH_HH */
  98