lily/pitch.cc

   1 /*
   2   musical-pitch.cc --  implement Pitch
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1998--2002 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7
   8  */
   9 #include "pitch.hh"
  10 #include "warn.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_ = n;
  19   alteration_ = a;
  20   octave_ = 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_string (a);
  27       s += ", notename = " + to_string (n);
  28       warning (s);
  29     }
  30   normalise ();
  31 }
  32
  33 Pitch::Pitch ()
  34 {
  35   notename_ = 0;
  36   alteration_ = 0;
  37   octave_ = 0;
  38 }
  39
  40 int
  41 Pitch::compare (Pitch const &m1, Pitch const &m2)
  42 {
  43   int o=  m1.octave_ - m2.octave_;
  44   int n = m1.notename_ - m2.notename_;
  45   int a = m1.alteration_ - m2.alteration_;
  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_ + octave_*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_;
  74   int n = notename_;
  75   while (n < 0)
  76     {
  77       n += 7;
  78       o --;
  79     }
  80   return (o + n / 7) * 12 + pitch_byte_a[n % 7] + alteration_;
  81 }
  82
  83 void
  84 Pitch::normalise ()
  85 {
  86   int pitch = semitone_pitch ();
  87   while (notename_ >= 7)
  88     {
  89       notename_ -= 7;
  90       octave_++;
  91       alteration_ -= semitone_pitch () - pitch;
  92     }
  93   while (notename_ < 0)
  94     {
  95       notename_ += 7;
  96       octave_--;
  97       alteration_ -= semitone_pitch () - pitch;
  98     }
  99   while (alteration_ >= 3)
 100     {
 101       if (notename_ == 6)
 102         {
 103           notename_ = 0;
 104           octave_++;
 105         }
 106       else
 107         notename_++;
 108
 109       alteration_ = 0;
 110       alteration_ -= semitone_pitch () - pitch;
 111     }
 112   while (alteration_ <= -3)
 113     {
 114       if (notename_ == 0)
 115         {
 116           notename_ = 6;
 117           octave_--;
 118         }
 119       else
 120         notename_--;
 121
 122       alteration_ = 0;
 123       alteration_ -= 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_ += delta.octave_;
 134   notename_ += delta.notename_;
 135
 136   int new_semi = semitone_pitch ();
 137   int delta_acc = new_semi - old_semi - delta_semi;
 138   alteration_ -= 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::string () const
 151 {
 152   int n = (notename_ + 2) % 7;
 153   String s = to_string (char (n + 'a'));
 154   if (alteration_)
 155     s += String (accname[alteration_ + 2]);
 156
 157   if (octave_ >= 0)
 158     {
 159       int o = octave_ + 1;
 160       while (o--)
 161         s += "'";
 162     }
 163   else if (octave_ < 0)
 164     {
 165       int o = (-octave_) - 1;
 166       while (o--)
 167         s += to_string (',');
 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_  + 1;   // account for c' = octave 1 iso. 0 4
 181   Pitch up_pitch (p);
 182   Pitch down_pitch (p);
 183
 184   up_pitch.alteration_ = alteration_;
 185   down_pitch.alteration_ = alteration_;
 186
 187   Pitch n = *this;
 188   up_pitch.up_to (notename_);
 189   down_pitch.down_to (notename_);
 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_ += oct_mod;
 198
 199   *this = n;
 200   return *this;
 201 }
 202
 203 void
 204 Pitch::up_to (int notename)
 205 {
 206   if (notename_  > notename)
 207     {
 208       octave_ ++;
 209     }
 210   notename_  = notename;
 211 }
 212
 213 void
 214 Pitch::down_to (int notename)
 215 {
 216   if (notename_ < notename)
 217     {
 218       octave_ --;
 219     }
 220   notename_ = notename;
 221 }
 222
 223 LY_DEFINE(ly_pitch_transpose,
 224           "ly-transpose-pitch", 2, 0, 0,
 225           (SCM p, SCM delta),
 226           "Transpose @var{p} by the amount @var{delta}, where @var{delta} is the
 227 pitch that central C is transposed to.
 228 ")
 229 {
 230   Pitch* t = unsmob_pitch (p);
 231   Pitch *d = unsmob_pitch (delta);
 232   SCM_ASSERT_TYPE(t, p, SCM_ARG1, __FUNCTION__, "pitch")  ;
 233   SCM_ASSERT_TYPE(d, delta, SCM_ARG1, __FUNCTION__, "pitch")  ;
 234
 235   Pitch tp =*t;
 236   tp.transpose (*d);
 237   return tp.smobbed_copy ();
 238 }
 239
 240 /****************************************************************/
 241
 242
 243 IMPLEMENT_TYPE_P (Pitch, "pitch?");
 244
 245 SCM
 246 Pitch::mark_smob (SCM)
 247 {
 248   return SCM_EOL;
 249 }
 250
 251 IMPLEMENT_SIMPLE_SMOBS (Pitch);
 252 int
 253 Pitch::print_smob (SCM s, SCM port, scm_print_state *)
 254 {
 255   Pitch  *r = (Pitch *) ly_cdr (s);
 256
 257   scm_puts ("#<Pitch ", port);
 258   scm_display (scm_makfrom0str (r->string ().to_str0 ()), port);
 259   scm_puts (" >", port);
 260
 261   return 1;
 262 }
 263
 264 SCM
 265 Pitch::equal_p (SCM a , SCM b)
 266 {
 267   Pitch  *p = (Pitch *) ly_cdr (a);
 268   Pitch  *q = (Pitch *) ly_cdr (b);
 269
 270   bool eq = p->notename_ == q->notename_
 271     && p->octave_ == q->octave_
 272     && p->alteration_ == q->alteration_;
 273
 274   return eq ? SCM_BOOL_T : SCM_BOOL_F;
 275 }
 276
 277 MAKE_SCHEME_CALLBACK (Pitch, less_p, 2);
 278 SCM
 279 Pitch::less_p (SCM p1, SCM p2)
 280 {
 281   Pitch *a = unsmob_pitch (p1);
 282   Pitch *b = unsmob_pitch (p2);
 283
 284   if (compare (*a, *b) < 0)
 285     return SCM_BOOL_T;
 286   else
 287     return SCM_BOOL_F;
 288 }
 289
 290 /*
 291   should add optional args
 292  */
 293
 294 LY_DEFINE(make_pitch, "make-pitch", 3, 0, 0,
 295           (SCM o, SCM n, SCM a),
 296           "
 297 @var{octave} is specified by an integer, zero for the octave containing
 298 middle C.  @var{note} is a number from 0 to 6, with 0 corresponding to C
 299 and 6 corresponding to B.  The shift is zero for a natural, negative for
 300 flats, or positive for sharps.
 301
 302 ")
 303 {
 304   SCM_ASSERT_TYPE(gh_number_p (o), o, SCM_ARG1, __FUNCTION__, "number");
 305   SCM_ASSERT_TYPE(gh_number_p (n), n, SCM_ARG2, __FUNCTION__, "number");
 306   SCM_ASSERT_TYPE(gh_number_p (a), a, SCM_ARG3, __FUNCTION__, "number");
 307
 308   Pitch p (gh_scm2int (o), gh_scm2int (n), gh_scm2int (a));
 309   return p.smobbed_copy ();
 310 }
 311
 312
 313 LY_DEFINE(pitch_octave, "pitch-octave", 1, 0, 0,
 314           (SCM pp),
 315           "extract the octave from pitch @var{p}.")
 316 {
 317   Pitch *p = unsmob_pitch (pp);
 318    SCM_ASSERT_TYPE(p, pp, SCM_ARG1, __FUNCTION__, "Pitch");
 319   int q = p->get_octave ();
 320
 321   return gh_int2scm (q);
 322 }
 323
 324 LY_DEFINE(pitch_alteration, "pitch-alteration", 1, 0, 0,
 325           (SCM pp),
 326           "extract the alteration from pitch  @var{p}.")
 327 {
 328   Pitch *p = unsmob_pitch (pp);
 329   SCM_ASSERT_TYPE(p, pp, SCM_ARG1, __FUNCTION__, "Pitch");
 330   int     q = p->get_alteration ();
 331
 332   return gh_int2scm (q);
 333 }
 334
 335 LY_DEFINE(pitch_notename, "pitch-notename", 1, 0, 0,
 336           (SCM pp),
 337           "extract the note name from pitch  @var{pp}.")
 338 {
 339   Pitch *p = unsmob_pitch (pp);
 340   SCM_ASSERT_TYPE(p, pp, SCM_ARG1, __FUNCTION__, "Pitch");
 341   int q  = p->get_notename ();
 342
 343   return gh_int2scm (q);
 344 }
 345
 346 LY_DEFINE(pitch_semitones,  "pitch-semitones", 1, 0, 0,
 347           (SCM pp),
 348           "calculate the number of semitones of @var{p} from central C.")
 349 {
 350   Pitch *p = unsmob_pitch (pp);
 351   SCM_ASSERT_TYPE(p, pp, SCM_ARG1, __FUNCTION__, "Pitch");
 352
 353   int q = p->semitone_pitch ();
 354
 355   // Was :
 356   //
 357   //int q = p->steps ();
 358   //
 359   // As the function is called "pitch_semitones", I assume it was a mistake !
 360   // Jiba
 361
 362   return gh_int2scm (q);
 363 }
 364
 365 LY_DEFINE(pitch_less, "pitch<?", 2,0,0, (SCM p1, SCM p2),
 366           "Is @var{p1} lower than @var{p2}? This uses lexicographic ordening.")
 367 {
 368   return Pitch::less_p (ly_car (p1),  ly_car (p2));
 369 }
 370
 371 SCM
 372 Pitch::smobbed_copy ()const
 373 {
 374   Pitch *  p = new Pitch (*this);
 375   return p->smobbed_self ();
 376 }
 377
 378 int
 379 Pitch::get_octave ()const
 380 {
 381   return octave_;
 382 }
 383
 384 int
 385 Pitch::get_notename () const
 386 {
 387   return notename_;
 388 }
 389
 390 int
 391 Pitch::get_alteration () const
 392 {
 393   return alteration_;
 394 }
 395