lily/musical-pitch.cc

   1 /*
   2   musical-pitch.cc --  implement Musical_pitch
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1998--1999 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7
   8  */
   9 #include "musical-pitch.hh"
  10 #include "debug.hh"
  11 #include "main.hh"
  12
  13 SCM
  14 to_scm (Musical_pitch p)
  15 {
  16   return gh_list (gh_int2scm (p.notename_i_),
  17                   gh_int2scm (p.accidental_i_),
  18                   gh_int2scm (p.octave_i_),
  19                   SCM_UNDEFINED);
  20 }
  21
  22 /*
  23   TODO: check -- is_pitch () ?
  24  */
  25 void
  26 scm_to (SCM s, Musical_pitch* p)
  27 {
  28   *p = Musical_pitch (gh_scm2int (gh_car (s)),
  29                       gh_scm2int (gh_cadr (s)),
  30                       gh_scm2int (gh_caddr (s)));
  31 }
  32
  33 Musical_pitch::Musical_pitch (int n, int a, int o)
  34 {
  35   notename_i_ = n;
  36   accidental_i_ = a;
  37   octave_i_ = o;
  38 }
  39
  40 void
  41 Musical_pitch::print () const
  42 {
  43 #ifndef NPRINT
  44   DEBUG_OUT << str ();
  45 #endif
  46 }
  47
  48 int
  49 Musical_pitch::compare (Musical_pitch const &m1, Musical_pitch const &m2)
  50 {
  51     int o=  m1.octave_i_ - m2.octave_i_;
  52   int n = m1.notename_i_ - m2.notename_i_;
  53   int a = m1.accidental_i_ - m2.accidental_i_;
  54
  55   if (o)
  56         return o;
  57   if (n)
  58         return n;
  59   if (a)
  60         return a;
  61   return 0;
  62 }
  63
  64 int
  65 Musical_pitch::steps () const
  66 {
  67   return  notename_i_ + octave_i_*7;
  68 }
  69
  70 /*
  71   should be settable from input to allow "viola"-mode
  72  */
  73 static Byte pitch_byte_a[  ] = { 0, 2, 4, 5, 7, 9, 11 };
  74
  75 int
  76 Musical_pitch::semitone_pitch () const
  77 {
  78   return  pitch_byte_a[ notename_i_ % 7 ] + accidental_i_ + octave_i_ * 12;
  79 }
  80
  81 void
  82 Musical_pitch::transpose (Musical_pitch delta)
  83 {
  84   int old_pitch = semitone_pitch ();
  85   int delta_pitch = delta.semitone_pitch ();
  86   octave_i_ += delta.octave_i_;
  87   notename_i_ += delta.notename_i_;
  88
  89
  90   while  (notename_i_ >= 7)
  91     {
  92       notename_i_ -= 7;
  93       octave_i_ ++;
  94     }
  95
  96   int new_pitch = semitone_pitch ();
  97   int delta_acc = new_pitch - old_pitch - delta_pitch;
  98   accidental_i_ -= delta_acc;
  99 }
 100
 101
 102 #if 0
 103 // nice test for internationalisation strings
 104 char const *accname[] = {"double flat", "flat", "natural",
 105                          "sharp" , "double sharp"};
 106 #else
 107 char const *accname[] = {"eses", "es", "", "is" , "isis"};
 108 #endif
 109
 110 String
 111 Musical_pitch::str () const
 112 {
 113   int n = (notename_i_ + 2) % 7;
 114   String s = to_str (char(n + 'a'));
 115   if (accidental_i_)
 116     s += String (accname[accidental_i_ + 2]);
 117
 118   if (octave_i_ > 0)
 119     {
 120       int o = octave_i_ + 1;
 121       while (o--)
 122         s += "'";
 123     }
 124   else if (octave_i_ <0)
 125     {
 126       int o = (-octave_i_) - 1;
 127       while (o--)
 128         s += to_str (',');
 129     }
 130
 131
 132   return s;
 133 }
 134
 135 /*
 136   change me to relative, counting from last pitch p
 137   return copy of resulting pitch
 138  */
 139 Musical_pitch
 140 Musical_pitch::to_relative_octave (Musical_pitch p)
 141 {
 142   int oct_mod = octave_i_  + 1; // account for c' = octave 1 iso. 0 4
 143   Musical_pitch up_pitch (p);
 144   Musical_pitch down_pitch (p);
 145
 146   up_pitch.accidental_i_ = accidental_i_;
 147   down_pitch.accidental_i_ = accidental_i_;
 148
 149   Musical_pitch n = *this;
 150   up_pitch.up_to (notename_i_);
 151   down_pitch.down_to (notename_i_);
 152
 153   int h = p.steps ();
 154   if (abs (up_pitch.steps () - h) < abs (down_pitch.steps () - h))
 155     n = up_pitch;
 156   else
 157     n = down_pitch;
 158
 159   n.octave_i_ += oct_mod;
 160
 161   *this = n;
 162   return *this;
 163 }
 164
 165 void
 166 Musical_pitch::up_to (int notename)
 167 {
 168   if (notename_i_  > notename)
 169     {
 170       octave_i_ ++;
 171     }
 172   notename_i_  = notename;
 173 }
 174
 175 void
 176 Musical_pitch::down_to (int notename)
 177 {
 178   if (notename_i_ < notename)
 179     {
 180       octave_i_ --;
 181     }
 182   notename_i_ = notename;
 183 }
 184