lily/lyric-engraver.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 1997--2010 Han-Wen Nienhuys <hanwen@xs4all.nl>
   5   Jan Nieuwenhuizen <janneke@gnu.org>
   6
   7   LilyPond is free software: you can redistribute it and/or modify
   8   it under the terms of the GNU General Public License as published by
   9   the Free Software Foundation, either version 3 of the License, or
  10   (at your option) any later version.
  11
  12   LilyPond is distributed in the hope that it will be useful,
  13   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15   GNU General Public License for more details.
  16
  17   You should have received a copy of the GNU General Public License
  18   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "context.hh"
  22 #include "engraver.hh"
  23 #include "item.hh"
  24 #include "note-head.hh"
  25 #include "stream-event.hh"
  26 #include "international.hh"
  27
  28 #include "translator.icc"
  29
  30 /**
  31    Generate texts for lyric syllables.  We only do one lyric at a time.
  32    Multiple copies of this engraver should be used to do multiple voices.
  33 */
  34 class Lyric_engraver : public Engraver
  35 {
  36 protected:
  37   void stop_translation_timestep ();
  38   void process_music ();
  39   DECLARE_TRANSLATOR_LISTENER (lyric);
  40
  41 public:
  42   TRANSLATOR_DECLARATIONS (Lyric_engraver);
  43
  44 private:
  45   Stream_event *event_;
  46   Item *text_;
  47   Item *last_text_;
  48
  49   Context *get_voice_context ();
  50 };
  51
  52 Lyric_engraver::Lyric_engraver ()
  53 {
  54   text_ = 0;
  55   last_text_ = 0;
  56   event_ = 0;
  57 }
  58
  59 IMPLEMENT_TRANSLATOR_LISTENER (Lyric_engraver, lyric);
  60 void
  61 Lyric_engraver::listen_lyric (Stream_event *ev)
  62 {
  63   ASSIGN_EVENT_ONCE (event_, ev);
  64 }
  65
  66 void
  67 Lyric_engraver::process_music ()
  68 {
  69   if (event_)
  70     {
  71       SCM text = event_->get_property ("text");
  72
  73       if (ly_is_equal (text, scm_from_locale_string (" ")))
  74         {
  75           if (last_text_)
  76             last_text_->set_property ("self-alignment-X", scm_from_int (LEFT));
  77         }
  78       /*
  79         "Empty" LyricText objects are needed to allow the Extender_engraver to
  80         distinguish between the end of a lyrics block and manual melismata.
  81       */
  82       text_ = make_item ("LyricText", event_->self_scm ());
  83     }
  84 }
  85
  86 Context *
  87 get_voice_to_lyrics (Context *lyrics)
  88 {
  89   SCM avc = lyrics->get_property ("associatedVoiceContext");
  90   if (Context *c = unsmob_context (avc))
  91     return c;
  92
  93   SCM voice_name = lyrics->get_property ("associatedVoice");
  94   string nm = lyrics->id_string ();
  95
  96   if (scm_is_string (voice_name))
  97     nm = ly_scm2string (voice_name);
  98   else if (nm == "")
  99     return 0;
 100   else
 101     {
 102       ssize idx = nm.rfind ('-');
 103       if (idx != NPOS)
 104         nm = nm.substr (0, idx);
 105     }
 106
 107   Context *parent = lyrics;
 108   Context *voice = 0;
 109   while (parent && !voice)
 110     {
 111       voice = find_context_below (parent, ly_symbol2scm ("Voice"), nm);
 112       parent = parent->get_parent_context ();
 113     }
 114
 115   if (voice)
 116     return voice;
 117
 118   parent = lyrics;
 119   voice = 0;
 120   while (parent && !voice)
 121     {
 122       voice = find_context_below (parent, ly_symbol2scm ("Voice"), "");
 123       parent = parent->get_parent_context ();
 124     }
 125
 126   return voice;
 127 }
 128
 129 Grob *
 130 get_current_note_head (Context *voice)
 131 {
 132   Moment now = voice->now_mom ();
 133   for (SCM s = voice->get_property ("busyGrobs");
 134        scm_is_pair (s); s = scm_cdr (s))
 135     {
 136       Grob *g = unsmob_grob (scm_cdar (s));;
 137       Moment *end_mom = unsmob_moment (scm_caar (s));
 138       if (!end_mom || !g)
 139         {
 140           programming_error ("busyGrobs invalid");
 141           continue;
 142         }
 143
 144       if (end_mom->main_part_ > now.main_part_
 145           && dynamic_cast<Item *> (g)
 146           && Note_head::has_interface (g))
 147         return g;
 148     }
 149
 150   return 0;
 151 }
 152
 153 void
 154 Lyric_engraver::stop_translation_timestep ()
 155 {
 156   if (text_)
 157     {
 158       Context *voice = get_voice_to_lyrics (context ());
 159
 160       if (voice)
 161         {
 162           Grob *head = get_current_note_head (voice);
 163
 164           if (head)
 165             {
 166               text_->set_parent (head, X_AXIS);
 167               if (melisma_busy (voice)
 168                   && !to_boolean (get_property ("ignoreMelismata")))
 169                 text_->set_property ("self-alignment-X",
 170                                      get_property("lyricMelismaAlignment"));
 171             }
 172           else
 173             {
 174               text_->warning (_ ("Lyric syllable does not have note. Use \\lyricsto or associatedVoice."));
 175               text_->set_property ("X-offset", scm_from_int (0));
 176             }
 177         }
 178
 179       last_text_ = text_;
 180       text_ = 0;
 181     }
 182   event_ = 0;
 183 }
 184
 185 ADD_TRANSLATOR (Lyric_engraver,
 186                 /* doc */
 187                 "Engrave text for lyrics.",
 188
 189                 /* create */
 190                 "LyricText ",
 191
 192                 /* read */
 193                 "ignoreMelismata "
 194                 "lyricMelismaAlignment ",
 195
 196                 /* write */
 197                 ""
 198                 );