2 extender-engraver.cc -- implement Extender_engraver
4 source file of the GNU LilyPond music typesetter
6 (c) 1999--2004 Glen Prideaux <glenprideaux@iname.com>,
7 Han-Wen Nienhuys <hanwen@cs.uu.nl>,
8 Jan Nieuwenhuizen <janneke@gnu.org>
12 #include "lyric-extender.hh"
14 #include "engraver.hh"
16 #include "group-interface.hh"
18 class Extender_engraver : public Engraver
22 Spanner * pending_extender_;
24 TRANSLATOR_DECLARATIONS (Extender_engraver);
27 virtual void acknowledge_grob (Grob_info);
28 virtual void finalize ();
29 virtual bool try_music (Music*);
30 virtual void stop_translation_timestep ();
31 virtual void process_music ();
39 Extender_engraver::Extender_engraver ()
42 pending_extender_ = 0;
47 Extender_engraver::try_music (Music* r)
58 Extender_engraver::process_music ()
62 extender_ = make_spanner ("LyricExtender", ev_->self_scm ());
68 Extender_engraver::acknowledge_grob (Grob_info i)
70 Item * item = dynamic_cast<Item*> (i.grob_);
73 && item->internal_has_interface (ly_symbol2scm ("lyric-syllable-interface")))
76 extender_->set_bound (LEFT, item);
78 if (pending_extender_)
79 pending_extender_->set_bound (RIGHT, item);
84 Extender_engraver::stop_translation_timestep ()
86 if (pending_extender_ && pending_extender_->get_bound (RIGHT))
88 pending_extender_ = 0;
91 if (extender_ || pending_extender_)
93 Context *voice = get_voice_to_lyrics (context ());
94 Grob* h = (voice) ? get_current_note_head (voice) : 0;
99 Pointer_group_interface::add_grob (extender_,
100 ly_symbol2scm ("heads"), h);
101 if (pending_extender_)
102 Pointer_group_interface::add_grob (pending_extender_,
103 ly_symbol2scm ("heads"), h);
108 pending_extender_ = extender_;
117 completize_extender (Spanner* sp)
119 if (!sp->get_bound (RIGHT))
121 SCM heads = sp->get_property ("heads");
122 if (ly_c_pair_p (heads))
124 Item* it = dynamic_cast<Item*> (unsmob_grob (ly_car (heads)));
126 sp->set_bound (RIGHT, it);
134 Extender_engraver::finalize ()
138 completize_extender (extender_);
140 if (!extender_->get_bound (RIGHT))
141 extender_->warning (_ ("unterminated extender"));
145 if (pending_extender_)
147 completize_extender (pending_extender_);
149 if (!pending_extender_->get_bound (RIGHT))
150 pending_extender_->warning (_("unterminated extender"));
151 pending_extender_ =0;
159 ENTER_DESCRIPTION (Extender_engraver,
160 /* descr */ "Create lyric extenders",
161 /* creats*/ "LyricExtender",
162 /* accepts */ "extender-event",
163 /* acks */ "lyric-syllable-interface",