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         {
  69           text_ = make_item ("LyricText", event_->self_scm ());
  70         }
  71     }
  72 }
  73
  74 Context *
  75 get_voice_to_lyrics (Context *lyrics)
  76 {
  77   SCM avc = lyrics->get_property ("associatedVoiceContext");
  78   if (Context *c = unsmob_context (avc))
  79     return c;
  80
  81   SCM voice_name = lyrics->get_property ("associatedVoice");
  82   string nm = lyrics->id_string ();
  83
  84   if (scm_is_string (voice_name))
  85     nm = ly_scm2string (voice_name);
  86   else if (nm == "")
  87     {
  88       return 0;
  89     }
  90   else
  91     {
  92       ssize idx = nm.rfind ('-');
  93       if (idx != NPOS)
  94         nm = nm.substr (0, idx);
  95     }
  96
  97   Context *parent = lyrics;
  98   Context *voice = 0;
  99   while (parent && !voice)
 100     {
 101       voice = find_context_below (parent, ly_symbol2scm ("Voice"), nm);
 102       parent = parent->get_parent_context ();
 103     }
 104
 105   if (voice)
 106     return voice;
 107
 108   parent = lyrics;
 109   voice = 0;
 110   while (parent && !voice)
 111     {
 112       voice = find_context_below (parent, ly_symbol2scm ("Voice"), "");
 113       parent = parent->get_parent_context ();
 114     }
 115
 116   return voice;
 117 }
 118
 119 Grob *
 120 get_current_note_head (Context *voice)
 121 {
 122   Moment now = voice->now_mom ();
 123   for (SCM s = voice->get_property ("busyGrobs");
 124        scm_is_pair (s); s = scm_cdr (s))
 125     {
 126       Grob *g = unsmob_grob (scm_cdar (s));;
 127       Moment *end_mom = unsmob_moment (scm_caar (s));
 128       if (!end_mom || !g)
 129         {
 130           programming_error ("busyGrobs invalid");
 131           continue;
 132         }
 133
 134       if (end_mom->main_part_ > now.main_part_
 135           && dynamic_cast<Item *> (g)
 136           && Note_head::has_interface (g))
 137         return g;
 138     }
 139
 140   return 0;
 141 }
 142
 143 void
 144 Lyric_engraver::stop_translation_timestep ()
 145 {
 146   if (text_)
 147     {
 148       Context *voice = get_voice_to_lyrics (context ());
 149
 150       if (voice)
 151         {
 152           Grob *head = get_current_note_head (voice);
 153
 154           if (head)
 155             {
 156               text_->set_parent (head, X_AXIS);
 157               if (melisma_busy (voice))
 158                 text_->set_property ("self-alignment-X", get_property("lyricMelismaAlignment"));
 159             }
 160           else
 161             {
 162               text_->warning (_ ("Lyric syllable does not have note. Use \\lyricsto or associatedVoice."));
 163               text_->set_property ("X-offset", scm_from_int (0));
 164             }
 165         }
 166
 167       last_text_ = text_;
 168       text_ = 0;
 169     }
 170   event_ = 0;
 171 }
 172
 173 ADD_TRANSLATOR (Lyric_engraver,
 174                 /* doc */
 175                 "Engrave text for lyrics.",
 176
 177                 /* create */
 178                 "LyricText ",
 179                 /* read */
 180                 "lyricMelismaAlignment ",
 181
 182                 /* write */
 183                 ""
 184                 );