lily/pitch.cc

   1 /*
   2   musical-pitch.cc --  implement Pitch
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1998--2001 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7
   8  */
   9 #include "pitch.hh"
  10 #include "debug.hh"
  11 #include "main.hh"
  12 #include "ly-smobs.icc"
  13
  14
  15
  16 Pitch::Pitch (int o, int n, int a)
  17 {
  18   notename_i_ = n;
  19   alteration_i_ = a;
  20   octave_i_ = o;
  21
  22   if (n < 0 || n >= 7 ||
  23       a < -2 || a > 2)
  24     {
  25       String s = _ ("Pitch arguments out of range");
  26       s += ": alteration = " + to_str (a);
  27       s += ", notename = " + to_str (n);
  28       warning (s);
  29     }
  30   normalise ();
  31 }
  32
  33 Pitch::Pitch ()
  34 {
  35   notename_i_ = 0;
  36   alteration_i_ = 0;
  37   octave_i_ = 0;
  38 }
  39
  40 int
  41 Pitch::compare (Pitch const &m1, Pitch const &m2)
  42 {
  43   int o=  m1.octave_i_ - m2.octave_i_;
  44   int n = m1.notename_i_ - m2.notename_i_;
  45   int a = m1.alteration_i_ - m2.alteration_i_;
  46
  47   if (o)
  48         return o;
  49   if (n)
  50         return n;
  51   if (a)
  52         return a;
  53   return 0;
  54 }
  55
  56 int
  57 Pitch::steps () const
  58 {
  59   return  notename_i_ + octave_i_*7;
  60 }
  61
  62 /*
  63   should be settable from input?
  64  */
  65 static Byte pitch_byte_a[  ] = { 0, 2, 4, 5, 7, 9, 11 };
  66
  67
  68 /* Calculate pitch height in 12th octave steps.  Don't assume
  69    normalised pitch as this function is used to normalise the pitch.  */
  70 int
  71 Pitch::semitone_pitch () const
  72 {
  73   int o = octave_i_;
  74   int n = notename_i_;
  75   while (n < 0)
  76     {
  77       n += 7;
  78       o --;
  79     }
  80   return (o + n / 7) * 12 + pitch_byte_a[n % 7] + alteration_i_;
  81 }
  82
  83 void
  84 Pitch::normalise ()
  85 {
  86   int pitch = semitone_pitch ();
  87   while (notename_i_ >= 7)
  88     {
  89       notename_i_ -= 7;
  90       octave_i_++;
  91       alteration_i_ -= semitone_pitch () - pitch;
  92     }
  93   while (notename_i_ < 0)
  94     {
  95       notename_i_ += 7;
  96       octave_i_--;
  97       alteration_i_ -= semitone_pitch () - pitch;
  98     }
  99   while (alteration_i_ >= 3)
 100     {
 101       if (notename_i_ == 6)
 102         {
 103           notename_i_ = 0;
 104           octave_i_++;
 105         }
 106       else
 107         notename_i_++;
 108
 109       alteration_i_ = 0;
 110       alteration_i_ -= semitone_pitch () - pitch;
 111     }
 112   while (alteration_i_ <= -3)
 113     {
 114       if (notename_i_ == 0)
 115         {
 116           notename_i_ = 6;
 117           octave_i_--;
 118         }
 119       else
 120         notename_i_--;
 121
 122       alteration_i_ = 0;
 123       alteration_i_ -= semitone_pitch () - pitch;
 124     }
 125 }
 126
 127 /* WHugh, wat een intervaas */
 128 void
 129 Pitch::transpose (Pitch delta)
 130 {
 131   int old_semi = semitone_pitch ();
 132   int delta_semi = delta.semitone_pitch ();
 133   octave_i_ += delta.octave_i_;
 134   notename_i_ += delta.notename_i_;
 135
 136   int new_semi = semitone_pitch ();
 137   int delta_acc = new_semi - old_semi - delta_semi;
 138   alteration_i_ -= delta_acc;
 139
 140   normalise ();
 141 }
 142
 143
 144 /* FIXME
 145    Merge with *pitch->text* funcs in chord-name.scm
 146  */
 147 char const *accname[] = {"eses", "es", "", "is" , "isis"};
 148
 149 String
 150 Pitch::str () const
 151 {
 152   int n = (notename_i_ + 2) % 7;
 153   String s = to_str (char (n + 'a'));
 154   if (alteration_i_)
 155     s += String (accname[alteration_i_ + 2]);
 156
 157   if (octave_i_ > 0)
 158     {
 159       int o = octave_i_ + 1;
 160       while (o--)
 161         s += "'";
 162     }
 163   else if (octave_i_ <0)
 164     {
 165       int o = (-octave_i_) - 1;
 166       while (o--)
 167         s += to_str (',');
 168     }
 169
 170   return s;
 171 }
 172
 173 /*
 174   change me to relative, counting from last pitch p
 175   return copy of resulting pitch
 176  */
 177 Pitch
 178 Pitch::to_relative_octave (Pitch p)
 179 {
 180   int oct_mod = octave_i_  + 1; // account for c' = octave 1 iso. 0 4
 181   Pitch up_pitch (p);
 182   Pitch down_pitch (p);
 183
 184   up_pitch.alteration_i_ = alteration_i_;
 185   down_pitch.alteration_i_ = alteration_i_;
 186
 187   Pitch n = *this;
 188   up_pitch.up_to (notename_i_);
 189   down_pitch.down_to (notename_i_);
 190
 191   int h = p.steps ();
 192   if (abs (up_pitch.steps () - h) < abs (down_pitch.steps () - h))
 193     n = up_pitch;
 194   else
 195     n = down_pitch;
 196
 197   n.octave_i_ += oct_mod;
 198
 199   *this = n;
 200   return *this;
 201 }
 202
 203 void
 204 Pitch::up_to (int notename)
 205 {
 206   if (notename_i_  > notename)
 207     {
 208       octave_i_ ++;
 209     }
 210   notename_i_  = notename;
 211 }
 212
 213 void
 214 Pitch::down_to (int notename)
 215 {
 216   if (notename_i_ < notename)
 217     {
 218       octave_i_ --;
 219     }
 220   notename_i_ = notename;
 221 }
 222
 223 ///MAKE_SCHEME_CALLBACK (Pitch, transpose, 2);
 224 ///transpose_proc?
 225 SCM
 226 Pitch::transpose (SCM p, SCM delta)
 227 {
 228   Pitch t = *unsmob_pitch (p);
 229   t.transpose (*unsmob_pitch (delta));
 230   return t.smobbed_copy ();
 231 }
 232
 233 static SCM
 234 pitch_transpose (SCM p, SCM delta)
 235 {
 236   return Pitch::transpose (p, delta);
 237 }
 238
 239 /****************************************************************/
 240
 241
 242 IMPLEMENT_TYPE_P (Pitch, "pitch?");
 243 IMPLEMENT_UNSMOB (Pitch, pitch);
 244 SCM
 245 Pitch::mark_smob (SCM)
 246 {
 247   return SCM_EOL;
 248 }
 249
 250 IMPLEMENT_SIMPLE_SMOBS (Pitch);
 251
 252
 253 int
 254 Pitch::print_smob (SCM s, SCM port, scm_print_state *)
 255 {
 256   Pitch  *r = (Pitch *) gh_cdr (s);
 257
 258   scm_puts ("#<Pitch ", port);
 259   scm_display (ly_str02scm (r->str ().ch_C ()), port);
 260   scm_puts (" >", port);
 261
 262   return 1;
 263 }
 264
 265 SCM
 266 Pitch::equal_p (SCM a , SCM b)
 267 {
 268   Pitch  *p = (Pitch *) gh_cdr (a);
 269   Pitch  *q = (Pitch *) gh_cdr (b);
 270
 271   bool eq = p->notename_i_ == q->notename_i_
 272     && p->octave_i_ == q->octave_i_
 273     && p->alteration_i_ == q->alteration_i_;
 274
 275   return eq ? SCM_BOOL_T : SCM_BOOL_F;
 276 }
 277
 278 MAKE_SCHEME_CALLBACK (Pitch, less_p, 2);
 279 SCM
 280 Pitch::less_p (SCM p1, SCM p2)
 281 {
 282   Pitch *a = unsmob_pitch (p1);
 283   Pitch *b = unsmob_pitch (p2);
 284
 285   if (compare (*a, *b) < 0)
 286     return SCM_BOOL_T;
 287   else
 288     return SCM_BOOL_F;
 289 }
 290
 291 /*
 292   should add optional args
 293  */
 294
 295 static SCM
 296 make_pitch (SCM o, SCM n, SCM a)
 297 {
 298   Pitch p (gh_scm2int (o), gh_scm2int (n), gh_scm2int (a));
 299   return p.smobbed_copy ();
 300 }
 301
 302 static SCM
 303 pitch_octave (SCM pp)
 304 {
 305   Pitch *p = unsmob_pitch (pp);
 306   int q = 0;
 307   if (!p)
 308     warning ("Not a pitch");
 309   else
 310     q = p->octave_i ();
 311
 312   return gh_int2scm (q);
 313 }
 314
 315 static SCM
 316 pitch_alteration (SCM pp)
 317 {
 318   Pitch *p = unsmob_pitch (pp);
 319   int q = 0;
 320   if (!p)
 321     warning ("Not a pitch");
 322   else
 323     q = p->alteration_i ();
 324
 325   return gh_int2scm (q);
 326 }
 327
 328 static SCM
 329 pitch_notename (SCM pp)
 330 {
 331   Pitch *p = unsmob_pitch (pp);
 332   int q = 0;
 333   if (!p)
 334     warning ("Not a pitch");
 335   else
 336     q = p->notename_i ();
 337
 338   return gh_int2scm (q);
 339 }
 340
 341 static SCM
 342 pitch_semitones (SCM pp)
 343 {
 344   Pitch *p = unsmob_pitch (pp);
 345   int q = 0;
 346   if (!p)
 347     warning ("Not a pitch");
 348   else
 349     q = p->steps ();
 350
 351   return gh_int2scm (q);
 352 }
 353
 354 static void
 355 add_funcs ()
 356 {
 357   // should take list?: (make-pitch ' (octave name accidental))
 358   scm_c_define_gsubr ("make-pitch", 3, 0, 0, (Scheme_function_unknown)make_pitch);
 359
 360   scm_c_define_gsubr ("pitch-octave", 1, 0, 0, (Scheme_function_unknown)pitch_octave);
 361   scm_c_define_gsubr ("pitch-notename", 1, 0, 0, (Scheme_function_unknown)pitch_notename);
 362   scm_c_define_gsubr ("pitch-alteration", 1, 0, 0, (Scheme_function_unknown)pitch_alteration);
 363   scm_c_define_gsubr ("pitch-semitones", 1, 0, 0, (Scheme_function_unknown)pitch_semitones);
 364   scm_c_define_gsubr ("Pitch::transpose", 2, 0, 0, (Scheme_function_unknown) pitch_transpose);
 365 }
 366
 367 ADD_SCM_INIT_FUNC (pitch, add_funcs);
 368
 369 SCM
 370 Pitch::smobbed_copy ()const
 371 {
 372   Pitch *  p = new Pitch (*this);
 373   return p->smobbed_self ();
 374 }
 375
 376 int
 377 Pitch::octave_i ()const
 378 {
 379   return octave_i_;
 380 }
 381
 382 int
 383 Pitch::notename_i () const
 384 {
 385   return notename_i_;
 386 }
 387
 388 int
 389 Pitch::alteration_i () const
 390 {
 391   return alteration_i_;
 392 }