lily/music-scheme.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 2005--2011 Han-Wen Nienhuys <hanwen@xs4all.nl>
   5
   6   LilyPond is free software: you can redistribute it and/or modify
   7   it under the terms of the GNU General Public License as published by
   8   the Free Software Foundation, either version 3 of the License, or
   9   (at your option) any later version.
  10
  11   LilyPond is distributed in the hope that it will be useful,
  12   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14   GNU General Public License for more details.
  15
  16   You should have received a copy of the GNU General Public License
  17   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "music.hh"
  21
  22 #include "duration.hh"
  23 #include "warn.hh"
  24
  25 LY_DEFINE (ly_music_length, "ly:music-length",
  26            1, 0, 0, (SCM mus),
  27            "Get the length of music expression @var{mus} and return"
  28            " it as a @code{Moment} object.")
  29 {
  30   LY_ASSERT_TYPE (unsmob_music, mus, 1);
  31   Music *sc = unsmob_music (mus);
  32   return sc->get_length ().smobbed_copy ();
  33 }
  34
  35 LY_DEFINE (ly_music_property, "ly:music-property",
  36            2, 1, 0, (SCM mus, SCM sym, SCM val),
  37            "Return the value for property @var{sym} of music expression"
  38            " @var{mus}.  If no value is found, return @var{val} or"
  39            " @code{'()} if @var{val} is not specified.")
  40 {
  41   LY_ASSERT_TYPE (unsmob_music, mus, 1);
  42   return ly_prob_property (mus, sym, val);
  43 }
  44
  45 LY_DEFINE (ly_music_set_property_x, "ly:music-set-property!",
  46            3, 0, 0, (SCM mus, SCM sym, SCM val),
  47            "Set property @var{sym} in music expression @var{mus} to"
  48            " @var{val}.")
  49 {
  50   LY_ASSERT_TYPE (unsmob_music, mus, 1);
  51
  52   return ly_prob_set_property_x (mus, sym, val);
  53 }
  54
  55
  56 /* todo:  property args */
  57 LY_DEFINE (ly_make_music, "ly:make-music",
  58            1, 0, 0, (SCM props),
  59            "Make a C++ @code{Music} object and initialize it with"
  60            " @var{props}.\n"
  61            "\n"
  62            "This function is for internal use and is only called by"
  63            " @code{make-music}, which is the preferred interface"
  64            " for creating music objects.")
  65 {
  66   Music *ms = new Music (props);
  67   return ms->unprotect ();
  68 }
  69
  70 LY_DEFINE (ly_music_p, "ly:music?",
  71            1, 0, 0, (SCM obj),
  72            "Is @var{obj} a music object?")
  73 {
  74   return scm_from_bool (unsmob_music (obj));
  75 }
  76
  77 /* todo: property args */
  78 LY_DEFINE (ly_music_mutable_properties, "ly:music-mutable-properties",
  79            1, 0, 0, (SCM mus),
  80            "Return an alist containing the mutable properties of @var{mus}."
  81            "  The immutable properties are not available, since they are"
  82            " constant and initialized by the @code{make-music} function.")
  83 {
  84   LY_ASSERT_TYPE (unsmob_music, mus, 1);
  85   Music *m = unsmob_music (mus);
  86   return m->get_property_alist (true);
  87 }
  88
  89 LY_DEFINE (ly_music_list_p, "ly:music-list?",
  90            1, 0, 0, (SCM lst),
  91            "Is @var{lst} a list of music objects?")
  92 {
  93   if (scm_list_p (lst) == SCM_BOOL_T)
  94     while (scm_is_pair (lst))
  95       {
  96         if (!unsmob_music (scm_car (lst)))
  97           return SCM_BOOL_F;
  98         lst = scm_cdr (lst);
  99       }
 100
 101   return SCM_BOOL_T;
 102 }
 103
 104 LY_DEFINE (ly_music_deep_copy, "ly:music-deep-copy",
 105            1, 0, 0, (SCM m),
 106            "Copy @var{m} and all sub expressions of@tie{}@var{m}.")
 107 {
 108   SCM copy = m;
 109   if (unsmob_music (m))
 110     {
 111       Music *mcopy = unsmob_music (m)->clone ();
 112       copy = mcopy->unprotect ();
 113     }
 114   else if (scm_is_pair (m))
 115     copy = scm_cons (ly_music_deep_copy (scm_car (m)),
 116                      ly_music_deep_copy (scm_cdr (m)));
 117   return copy;
 118 }
 119
 120 LY_DEFINE (ly_music_transpose, "ly:music-transpose",
 121            2, 0, 0, (SCM m, SCM p),
 122            "Transpose @var{m} such that central@tie{}C is mapped"
 123            " to@tie{}@var{p}.  Return@tie{}@var{m}.")
 124 {
 125   LY_ASSERT_TYPE (unsmob_music, m, 1);
 126   LY_ASSERT_SMOB (Pitch, p, 2);
 127
 128   Music *sc = unsmob_music (m);
 129   Pitch *sp = unsmob_pitch (p);
 130
 131   sc->transpose (*sp);
 132   // SCM_UNDEFINED ?
 133   return sc->self_scm ();
 134 }
 135
 136 /*
 137   TODO: should take moment factor?
 138 */
 139 LY_DEFINE (ly_music_compress, "ly:music-compress",
 140            2, 0, 0, (SCM m, SCM factor),
 141            "Compress music object@tie{}@var{m} by moment @var{factor}.")
 142 {
 143   LY_ASSERT_TYPE (unsmob_music, m, 1);
 144   LY_ASSERT_TYPE (unsmob_moment, factor, 2);
 145
 146   Music *sc = unsmob_music (m);
 147   sc->compress (*unsmob_moment (factor));
 148   return sc->self_scm ();
 149 }
 150
 151 LY_DEFINE (ly_music_duration_length, "ly:music-duration-length", 1, 0, 0,
 152            (SCM mus),
 153            "Extract the duration field from @var{mus} and return the"
 154            " length.")
 155 {
 156   LY_ASSERT_TYPE (unsmob_music, mus, 1);
 157   Music *m = unsmob_music (mus);
 158
 159   Duration *d = unsmob_duration (m->get_property ("duration"));
 160   Moment len;
 161
 162   if (d)
 163     len = d->get_length ();
 164   else
 165     programming_error ("music has no duration");
 166   return len.smobbed_copy ();
 167 }
 168
 169 LY_DEFINE (ly_music_duration_compress, "ly:music-duration-compress", 2, 0, 0,
 170            (SCM mus, SCM fact),
 171            "Compress @var{mus} by factor @var{fact}, which is a"
 172            " @code{Moment}.")
 173 {
 174   LY_ASSERT_TYPE (unsmob_music, mus, 1);
 175   LY_ASSERT_SMOB (Moment, fact, 2);
 176
 177   Music *m = unsmob_music (mus);
 178   Moment *f = unsmob_moment (fact);
 179
 180   Duration *d = unsmob_duration (m->get_property ("duration"));
 181   if (d)
 182     m->set_property ("duration", d->compressed (f->main_part_).smobbed_copy ());
 183   return SCM_UNSPECIFIED;
 184 }
 185
 186 /*
 187   This is hairy, since the scale in a key-change event may contain
 188   octaveless notes.
 189
 190
 191   TODO: this should use ly:pitch.
 192 */
 193 LY_DEFINE (ly_transpose_key_alist, "ly:transpose-key-alist",
 194            2, 0, 0, (SCM l, SCM pit),
 195            "Make a new key alist of@tie{}@var{l} transposed by"
 196            " pitch @var{pit}.")
 197 {
 198   SCM newlist = SCM_EOL;
 199   Pitch *p = unsmob_pitch (pit);
 200
 201   for (SCM s = l; scm_is_pair (s); s = scm_cdr (s))
 202     {
 203       SCM key = scm_caar (s);
 204       SCM alter = scm_cdar (s);
 205       if (scm_is_pair (key))
 206         {
 207           Pitch orig (scm_to_int (scm_car (key)),
 208                       scm_to_int (scm_cdr (key)),
 209                       ly_scm2rational (alter));
 210
 211           orig = orig.transposed (*p);
 212
 213           SCM key = scm_cons (scm_from_int (orig.get_octave ()),
 214                               scm_from_int (orig.get_notename ()));
 215
 216           newlist = scm_cons (scm_cons (key, ly_rational2scm (orig.get_alteration ())),
 217                               newlist);
 218         }
 219       else if (scm_is_number (key))
 220         {
 221           Pitch orig (0, scm_to_int (key), ly_scm2rational (alter));
 222           orig = orig.transposed (*p);
 223
 224           key = scm_from_int (orig.get_notename ());
 225           alter = ly_rational2scm (orig.get_alteration ());
 226           newlist = scm_cons (scm_cons (key, alter), newlist);
 227         }
 228     }
 229   return scm_reverse_x (newlist, SCM_EOL);
 230 }
 231