+Music::compress (Moment factor)
+{
+ SCM elt = get_property ("element");
+
+ if (Music *m = unsmob_music (elt))
+ m->compress (factor);
+
+ compress_music_list (get_property ("elements"), factor);
+ Duration *d = unsmob_duration (get_property ("duration"));
+ if (d)
+ set_property ("duration", d->compressed (factor.main_part_).smobbed_copy ());
+}
+
+/*
+ This mutates alist. Hence, make sure that it is not shared
+*/
+void
+transpose_mutable (SCM alist, Pitch delta)
+{
+ for (SCM s = alist; scm_is_pair (s); s = scm_cdr (s))
+ {
+ SCM entry = scm_car (s);
+ SCM prop = scm_car (entry);
+ SCM val = scm_cdr (entry);
+ SCM new_val = val;
+
+ if (Pitch *p = unsmob_pitch (val))
+ {
+ Pitch transposed = p->transposed (delta);
+ if (transposed.get_alteration ().abs () > Rational (1,1))
+ {
+ warning (_f ("transposition by %s makes alteration larger than double",
+ delta.to_string ()));
+ }
+
+ new_val = transposed.smobbed_copy ();
+ }
+ else if (prop == ly_symbol2scm ("element"))
+ {
+ if (Music *m = unsmob_music (val))
+ m->transpose (delta);
+ }
+ else if (prop == ly_symbol2scm ("elements"))
+ transpose_music_list (val, delta);
+ else if (prop == ly_symbol2scm ("pitch-alist") &&
+ scm_is_pair (val))
+ new_val = ly_transpose_key_alist (val, delta.smobbed_copy ());
+
+ if (val != new_val)
+ scm_set_cdr_x (entry , new_val);
+ }
+}
+
+void
+Music::transpose (Pitch delta)
+{
+ if (to_boolean (get_property ("untransposable")))
+ return;
+
+ transpose_mutable (mutable_property_alist_, delta);
+}
+
+void
+Music::set_spot (Input ip)
+{
+ set_property ("origin", make_input (ip));
+}
+
+Input *
+Music::origin () const
+{
+ Input *ip = unsmob_input (get_property ("origin"));
+ return ip ? ip : &dummy_input_global;
+}
+
+/*
+ ES TODO: This method should probably be reworked or junked.
+*/
+Stream_event *
+Music::to_event () const
+{
+ SCM class_name = ly_camel_case_2_lisp_identifier (get_property ("name"));
+
+ // catch programming mistakes.
+ if (!internal_is_music_type (class_name))
+ {
+ programming_error ("Not a music type");
+ }
+
+ Stream_event *e = new Stream_event (class_name, mutable_property_alist_);
+ Moment length = get_length ();
+ if (length.to_bool ())
+ e->set_property ("length", length.smobbed_copy ());
+
+ // articulations as events.
+ SCM art_mus = e->get_property ("articulations");
+ if (scm_is_pair (art_mus))
+ {
+ SCM art_ev = SCM_EOL;
+ for (; scm_is_pair (art_mus); art_mus = scm_cdr (art_mus))
+ {
+ Music *m = unsmob_music (scm_car (art_mus));
+ SCM ev = m ? m->to_event ()->unprotect () : scm_car (art_mus);
+ art_ev = scm_cons (ev, art_ev);
+ }
+ e->set_property ("articulations", scm_reverse_x (art_ev, SCM_EOL));
+ }
+
+ /*
+ ES TODO: This is a temporary fix. Stream_events should not be
+ aware of music.
+ */
+ e->set_property ("music-cause", self_scm ());
+
+ return e;
+}
+
+void
+Music::send_to_context (Context *c)
+{
+ Stream_event *ev = to_event ();
+ c->event_source ()->broadcast (ev);
+ ev->unprotect ();
+}
+
+Music *
+make_music_by_name (SCM sym)
+{
+ SCM make_music_proc = ly_lily_module_constant ("make-music");
+ SCM rv = scm_call_1 (make_music_proc, sym);
+
+ /* UGH. */
+ Music *m = unsmob_music (rv);
+ m->protect ();
+ return m;
+}
+
+MAKE_SCHEME_CALLBACK (Music, duration_length_callback, 1);
+SCM
+Music::duration_length_callback (SCM m)
+{
+ Music *me = unsmob_music (m);
+ Duration *d = unsmob_duration (me->get_property ("duration"));
+
+ Moment mom;
+ if (d)
+ mom = d->get_length ();
+ return mom.smobbed_copy ();
+}
+
+Music *
+unsmob_music (SCM m)