lily/extender-engraver.cc

   1 /*
   2   extender-engraver.cc -- implement Extender_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1999--2008 Glen Prideaux <glenprideaux@iname.com>,
   7   Han-Wen Nienhuys <hanwen@xs4all.nl>,
   8   Jan Nieuwenhuizen <janneke@gnu.org>
   9 */
  10
  11 #include "context.hh"
  12 #include "engraver.hh"
  13 #include "international.hh"
  14 #include "item.hh"
  15 #include "lyric-extender.hh"
  16 #include "note-head.hh"
  17 #include "pointer-group-interface.hh"
  18 #include "stream-event.hh"
  19 #include "warn.hh"
  20 #include "spanner.hh"
  21
  22 #include "translator.icc"
  23
  24 void completize_extender (Spanner *sp);
  25
  26 class Extender_engraver : public Engraver
  27 {
  28   Stream_event *ev_;
  29   Spanner *extender_;
  30   Spanner *pending_extender_;
  31
  32 public:
  33   TRANSLATOR_DECLARATIONS (Extender_engraver);
  34
  35 protected:
  36   DECLARE_TRANSLATOR_LISTENER (extender);
  37   DECLARE_ACKNOWLEDGER (lyric_syllable);
  38
  39   virtual void finalize ();
  40
  41   void stop_translation_timestep ();
  42   void process_music ();
  43 };
  44
  45 Extender_engraver::Extender_engraver ()
  46 {
  47   extender_ = 0;
  48   pending_extender_ = 0;
  49   ev_ = 0;
  50 }
  51
  52 IMPLEMENT_TRANSLATOR_LISTENER (Extender_engraver, extender);
  53 void
  54 Extender_engraver::listen_extender (Stream_event *ev)
  55 {
  56   ASSIGN_EVENT_ONCE (ev_, ev);
  57 }
  58
  59 void
  60 Extender_engraver::process_music ()
  61 {
  62   if (ev_)
  63     extender_ = make_spanner ("LyricExtender", ev_->self_scm ());
  64 }
  65
  66 void
  67 Extender_engraver::acknowledge_lyric_syllable (Grob_info i)
  68 {
  69   Item *item = i.item ();
  70   if (extender_)
  71     extender_->set_bound (LEFT, item);
  72
  73   if (pending_extender_)
  74     {
  75       pending_extender_->set_object ("next", item->self_scm ());
  76       completize_extender (pending_extender_);
  77       pending_extender_ = 0;
  78     }
  79 }
  80
  81 void
  82 Extender_engraver::stop_translation_timestep ()
  83 {
  84   if (extender_ || pending_extender_)
  85     {
  86       Context *voice = get_voice_to_lyrics (context ());
  87       Grob *h = voice ? get_current_note_head (voice) : 0;
  88
  89       if (h)
  90         {
  91           if (extender_)
  92             {
  93               Pointer_group_interface::add_grob (extender_,
  94                                                  ly_symbol2scm ("heads"), h);
  95             }
  96
  97           if (pending_extender_)
  98             {
  99               Pointer_group_interface::add_grob (pending_extender_,
 100                                                  ly_symbol2scm ("heads"), h);
 101             }
 102         }
 103       else
 104         {
 105           if (pending_extender_
 106               && !get_property ("extendersOverRests"))
 107             {
 108               completize_extender (pending_extender_);
 109               pending_extender_ = 0;
 110             }
 111
 112         }
 113       if (extender_)
 114         {
 115           pending_extender_ = extender_;
 116           extender_ = 0;
 117         }
 118     }
 119
 120   ev_ = 0;
 121 }
 122
 123 void
 124 completize_extender (Spanner *sp)
 125 {
 126   if (!sp->get_bound (RIGHT))
 127     {
 128       extract_item_set (sp, "heads", heads);
 129       if (heads.size ())
 130         sp->set_bound (RIGHT, heads.back ());
 131     }
 132 }
 133
 134 void
 135 Extender_engraver::finalize ()
 136 {
 137   if (extender_)
 138     {
 139       completize_extender (extender_);
 140
 141       if (!extender_->get_bound (RIGHT))
 142         extender_->warning (_ ("unterminated extender"));
 143       extender_ = 0;
 144     }
 145
 146   if (pending_extender_)
 147     {
 148       completize_extender (pending_extender_);
 149
 150       if (!pending_extender_->get_bound (RIGHT))
 151         pending_extender_->warning (_ ("unterminated extender"));
 152       pending_extender_ = 0;
 153     }
 154 }
 155
 156 ADD_ACKNOWLEDGER (Extender_engraver, lyric_syllable);
 157 ADD_TRANSLATOR (Extender_engraver,
 158                 /* doc */
 159                 "Create lyric extenders.",
 160
 161                 /* create */
 162                 "LyricExtender ",
 163
 164                 /* read */
 165                 "extendersOverRests ",
 166
 167                 /* write */
 168                 ""
 169                 );