lily/lyric-engraver.cc

   1 /*
   2   lyric-engraver.cc -- implement Lyric_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1997--2009 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7   Jan Nieuwenhuizen <janneke@gnu.org>
   8 */
   9
  10 #include "context.hh"
  11 #include "engraver.hh"
  12 #include "item.hh"
  13 #include "note-head.hh"
  14 #include "stream-event.hh"
  15 #include "international.hh"
  16
  17 #include "translator.icc"
  18
  19 /**
  20    Generate texts for lyric syllables.  We only do one lyric at a time.
  21    Multiple copies of this engraver should be used to do multiple voices.
  22 */
  23 class Lyric_engraver : public Engraver
  24 {
  25 protected:
  26   void stop_translation_timestep ();
  27   void process_music ();
  28   DECLARE_TRANSLATOR_LISTENER (lyric);
  29
  30 public:
  31   TRANSLATOR_DECLARATIONS (Lyric_engraver);
  32
  33 private:
  34   Stream_event *event_;
  35   Item *text_;
  36   Item *last_text_;
  37
  38   Context *get_voice_context ();
  39 };
  40
  41 Lyric_engraver::Lyric_engraver ()
  42 {
  43   text_ = 0;
  44   last_text_ = 0;
  45   event_ = 0;
  46 }
  47
  48 IMPLEMENT_TRANSLATOR_LISTENER (Lyric_engraver, lyric);
  49 void
  50 Lyric_engraver::listen_lyric (Stream_event *ev)
  51 {
  52   ASSIGN_EVENT_ONCE (event_, ev);
  53 }
  54
  55 void
  56 Lyric_engraver::process_music ()
  57 {
  58   if (event_)
  59     {
  60       SCM text = event_->get_property ("text");
  61
  62       if (ly_is_equal (text, scm_from_locale_string (" ")))
  63         {
  64           if (last_text_)
  65             last_text_->set_property ("self-alignment-X", scm_from_int (LEFT));
  66         }
  67       else
  68         text_ = make_item ("LyricText", event_->self_scm ());
  69     }
  70 }
  71
  72 Context *
  73 get_voice_to_lyrics (Context *lyrics)
  74 {
  75   SCM avc = lyrics->get_property ("associatedVoiceContext");
  76   if (Context *c = unsmob_context (avc))
  77     return c;
  78
  79   SCM voice_name = lyrics->get_property ("associatedVoice");
  80   string nm = lyrics->id_string ();
  81
  82   if (scm_is_string (voice_name))
  83     nm = ly_scm2string (voice_name);
  84   else if (nm == "")
  85     return 0;
  86   else
  87     {
  88       ssize idx = nm.rfind ('-');
  89       if (idx != NPOS)
  90         nm = nm.substr (0, idx);
  91     }
  92
  93   Context *parent = lyrics;
  94   Context *voice = 0;
  95   while (parent && !voice)
  96     {
  97       voice = find_context_below (parent, ly_symbol2scm ("Voice"), nm);
  98       parent = parent->get_parent_context ();
  99     }
 100
 101   if (voice)
 102     return voice;
 103
 104   parent = lyrics;
 105   voice = 0;
 106   while (parent && !voice)
 107     {
 108       voice = find_context_below (parent, ly_symbol2scm ("Voice"), "");
 109       parent = parent->get_parent_context ();
 110     }
 111
 112   return voice;
 113 }
 114
 115 Grob *
 116 get_current_note_head (Context *voice)
 117 {
 118   Moment now = voice->now_mom ();
 119   for (SCM s = voice->get_property ("busyGrobs");
 120        scm_is_pair (s); s = scm_cdr (s))
 121     {
 122       Grob *g = unsmob_grob (scm_cdar (s));;
 123       Moment *end_mom = unsmob_moment (scm_caar (s));
 124       if (!end_mom || !g)
 125         {
 126           programming_error ("busyGrobs invalid");
 127           continue;
 128         }
 129
 130       if (end_mom->main_part_ > now.main_part_
 131           && dynamic_cast<Item *> (g)
 132           && Note_head::has_interface (g))
 133         return g;
 134     }
 135
 136   return 0;
 137 }
 138
 139 void
 140 Lyric_engraver::stop_translation_timestep ()
 141 {
 142   if (text_)
 143     {
 144       Context *voice = get_voice_to_lyrics (context ());
 145
 146       if (voice)
 147         {
 148           Grob *head = get_current_note_head (voice);
 149
 150           if (head)
 151             {
 152               text_->set_parent (head, X_AXIS);
 153               if (melisma_busy (voice)
 154                   && !to_boolean (get_property ("ignoreMelismata")))
 155                 text_->set_property ("self-alignment-X",
 156                                      get_property("lyricMelismaAlignment"));
 157             }
 158           else
 159             {
 160               text_->warning (_ ("Lyric syllable does not have note. Use \\lyricsto or associatedVoice."));
 161               text_->set_property ("X-offset", scm_from_int (0));
 162             }
 163         }
 164
 165       last_text_ = text_;
 166       text_ = 0;
 167     }
 168   event_ = 0;
 169 }
 170
 171 ADD_TRANSLATOR (Lyric_engraver,
 172                 /* doc */
 173                 "Engrave text for lyrics.",
 174
 175                 /* create */
 176                 "LyricText ",
 177
 178                 /* read */
 179                 "ignoreMelismata "
 180                 "lyricMelismaAlignment ",
 181
 182                 /* write */
 183                 ""
 184                 );