lily/music-scheme.cc

   1 /*
   2   music-scheme.cc -- implement Music bindings
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2005--2009 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7 */
   8
   9 #include "music.hh"
  10
  11 #include "duration.hh"
  12 #include "warn.hh"
  13
  14 LY_DEFINE (ly_music_length, "ly:music-length",
  15            1, 0, 0, (SCM mus),
  16            "Get the length of music expression @var{mus} and return"
  17            " it as a @code{Moment} object.")
  18 {
  19   LY_ASSERT_TYPE (unsmob_music, mus, 1);
  20   Music *sc = unsmob_music (mus);
  21   return sc->get_length ().smobbed_copy ();
  22 }
  23
  24 LY_DEFINE (ly_music_property,
  25            "ly:music-property", 2, 1, 0, (SCM mus, SCM sym, SCM dfault),
  26            "Get the property @var{sym} of music expression @var{mus}."
  27            "  If @var{sym} is undefined, return @code{'()}.")
  28 {
  29   LY_ASSERT_TYPE (unsmob_music, mus, 1);
  30   return ly_prob_property (mus, sym, dfault);
  31 }
  32
  33 LY_DEFINE (ly_music_set_property_x, "ly:music-set-property!",
  34            3, 0, 0, (SCM mus, SCM sym, SCM val),
  35            "Set property @var{sym} in music expression @var{mus} to"
  36            " @var{val}.")
  37 {
  38   LY_ASSERT_TYPE (unsmob_music, mus, 1);
  39
  40   return ly_prob_set_property_x (mus, sym, val);
  41 }
  42
  43
  44 /* todo:  property args */
  45 LY_DEFINE (ly_make_music, "ly:make-music",
  46            1, 0, 0, (SCM props),
  47            "Make a C++ @code{Music} object and initialize it with"
  48            " @var{props}.\n"
  49            "\n"
  50            "This function is for internal use and is only called by"
  51            " @code{make-music}, which is the preferred interface"
  52            " for creating music objects.")
  53 {
  54   Music *ms = new Music (props);
  55   return ms->unprotect ();
  56 }
  57
  58 LY_DEFINE (ly_music_p, "ly:music?",
  59            1, 0, 0, (SCM obj),
  60            "Type predicate.")
  61 {
  62   return scm_from_bool (unsmob_music (obj));
  63 }
  64
  65 /* todo: property args */
  66 LY_DEFINE (ly_music_mutable_properties, "ly:music-mutable-properties",
  67            1, 0, 0, (SCM mus),
  68            "Return an alist containing the mutable properties of @var{mus}."
  69            "  The immutable properties are not available, since they are"
  70            " constant and initialized by the @code{make-music} function.")
  71 {
  72   LY_ASSERT_TYPE (unsmob_music, mus, 1);
  73   Music *m = unsmob_music (mus);
  74   return m->get_property_alist (true);
  75 }
  76
  77 LY_DEFINE (ly_music_list_p, "ly:music-list?",
  78            1, 0, 0, (SCM lst),
  79            "Type predicate: Return true if @var{lst} is a list"
  80            " of music objects.")
  81 {
  82   if (scm_list_p (lst) == SCM_BOOL_T)
  83     while (scm_is_pair (lst))
  84       {
  85         if (!unsmob_music (scm_car (lst)))
  86           return SCM_BOOL_F;
  87         lst = scm_cdr (lst);
  88       }
  89
  90   return SCM_BOOL_T;
  91 }
  92
  93 LY_DEFINE (ly_music_deep_copy, "ly:music-deep-copy",
  94            1, 0, 0, (SCM m),
  95            "Copy @var{m} and all sub expressions of@tie{}@var{m}.")
  96 {
  97   SCM copy = m;
  98   if (unsmob_music (m))
  99     {
 100       Music *mcopy = unsmob_music (m)->clone ();
 101       copy = mcopy->unprotect ();
 102     }
 103   else if (scm_is_pair (m))
 104     copy = scm_cons (ly_music_deep_copy (scm_car (m)),
 105                      ly_music_deep_copy (scm_cdr (m)));
 106   return copy;
 107 }
 108
 109 LY_DEFINE (ly_music_transpose, "ly:music-transpose",
 110            2, 0, 0, (SCM m, SCM p),
 111            "Transpose @var{m} such that central@tie{}C is mapped"
 112            " to@tie{}@var{p}.  Return@tie{}@var{m}.")
 113 {
 114   LY_ASSERT_TYPE (unsmob_music, m, 1);
 115   LY_ASSERT_SMOB (Pitch, p, 2);
 116
 117   Music *sc = unsmob_music (m);
 118   Pitch *sp = unsmob_pitch (p);
 119
 120   sc->transpose (*sp);
 121   // SCM_UNDEFINED ?
 122   return sc->self_scm ();
 123 }
 124
 125 /*
 126   TODO: should take moment factor?
 127 */
 128 LY_DEFINE (ly_music_compress, "ly:music-compress",
 129            2, 0, 0, (SCM m, SCM factor),
 130            "Compress music object@tie{}@var{m} by moment @var{factor}.")
 131 {
 132   LY_ASSERT_TYPE (unsmob_music, m, 1);
 133   LY_ASSERT_TYPE (unsmob_moment, factor, 2);
 134
 135   Music *sc = unsmob_music (m);
 136   sc->compress (*unsmob_moment (factor));
 137   return sc->self_scm ();
 138 }
 139
 140 LY_DEFINE (ly_music_duration_length, "ly:music-duration-length", 1, 0, 0,
 141            (SCM mus),
 142            "Extract the duration field from @var{mus} and return the"
 143            " length.")
 144 {
 145   LY_ASSERT_TYPE (unsmob_music, mus, 1);
 146   Music *m = unsmob_music (mus);
 147
 148   Duration *d = unsmob_duration (m->get_property ("duration"));
 149   Moment len;
 150
 151   if (d)
 152     len = d->get_length ();
 153   else
 154     programming_error ("music has no duration");
 155   return len.smobbed_copy ();
 156 }
 157
 158 LY_DEFINE (ly_music_duration_compress, "ly:music-duration-compress", 2, 0, 0,
 159            (SCM mus, SCM fact),
 160            "Compress @var{mus} by factor @var{fact}, which is a"
 161            " @code{Moment}.")
 162 {
 163   LY_ASSERT_TYPE (unsmob_music, mus, 1);
 164   LY_ASSERT_SMOB (Moment, fact, 2);
 165
 166   Music *m = unsmob_music (mus);
 167   Moment *f = unsmob_moment (fact);
 168
 169   Duration *d = unsmob_duration (m->get_property ("duration"));
 170   if (d)
 171     m->set_property ("duration", d->compressed (f->main_part_).smobbed_copy ());
 172   return SCM_UNSPECIFIED;
 173 }
 174
 175 /*
 176   This is hairy, since the scale in a key-change event may contain
 177   octaveless notes.
 178
 179
 180   TODO: this should use ly:pitch.
 181 */
 182 LY_DEFINE (ly_transpose_key_alist, "ly:transpose-key-alist",
 183            2, 0, 0, (SCM l, SCM pit),
 184            "Make a new key alist of@tie{}@var{l} transposed by"
 185            " pitch @var{pit}.")
 186 {
 187   SCM newlist = SCM_EOL;
 188   Pitch *p = unsmob_pitch (pit);
 189
 190   for (SCM s = l; scm_is_pair (s); s = scm_cdr (s))
 191     {
 192       SCM key = scm_caar (s);
 193       SCM alter = scm_cdar (s);
 194       if (scm_is_pair (key))
 195         {
 196           Pitch orig (scm_to_int (scm_car (key)),
 197                       scm_to_int (scm_cdr (key)),
 198                       ly_scm2rational (alter));
 199
 200           orig = orig.transposed (*p);
 201
 202           SCM key = scm_cons (scm_from_int (orig.get_octave ()),
 203                               scm_from_int (orig.get_notename ()));
 204
 205           newlist = scm_cons (scm_cons (key, ly_rational2scm (orig.get_alteration ())),
 206                               newlist);
 207         }
 208       else if (scm_is_number (key))
 209         {
 210           Pitch orig (0, scm_to_int (key), ly_scm2rational (alter));
 211           orig = orig.transposed (*p);
 212
 213           key = scm_from_int (orig.get_notename ());
 214           alter = ly_rational2scm (orig.get_alteration ());
 215           newlist = scm_cons (scm_cons (key, alter), newlist);
 216         }
 217     }
 218   return scm_reverse_x (newlist, SCM_EOL);
 219 }
 220