1 /*
2   This file is part of LilyPond, the GNU music typesetter.
3 
4   Copyright (C) 2000--2021 Han-Wen Nienhuys <hanwen@xs4all.nl>, Glen Prideaux <glenprideaux@iname.com>
5 
6   LilyPond is free software: you can redistribute it and/or modify
7   it under the terms of the GNU General Public License as published by
8   the Free Software Foundation, either version 3 of the License, or
9   (at your option) any later version.
10 
11   LilyPond is distributed in the hope that it will be useful,
12   but WITHOUT ANY WARRANTY; without even the implied warranty of
13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14   GNU General Public License for more details.
15 
16   You should have received a copy of the GNU General Public License
17   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
18 */
19 
20 #include "engraver.hh"
21 #include "side-position-interface.hh"
22 #include "text-interface.hh"
23 #include "item.hh"
24 
25 class Stanza_number_engraver : public Engraver
26 {
27   Item *text_;
28 
29   SCM last_stanza_;
30 public:
31   TRANSLATOR_DECLARATIONS (Stanza_number_engraver);
32   void process_music ();
33   void derived_mark () const override;
34   void stop_translation_timestep ();
35   void acknowledge_lyric_syllable (Grob_info);
36 };
37 
38 void
derived_mark() const39 Stanza_number_engraver::derived_mark () const
40 {
41   scm_gc_mark (last_stanza_);
42 }
43 
44 /*
45   TODO: should make engraver that collects all the stanzas on a higher
46   level, and then groups them to the side. Stanza numbers should be
47   all aligned.
48 */
49 
Stanza_number_engraver(Context * c)50 Stanza_number_engraver::Stanza_number_engraver (Context *c)
51   : Engraver (c)
52 {
53   text_ = 0;
54   last_stanza_ = SCM_EOL;
55 }
56 
57 void
process_music()58 Stanza_number_engraver::process_music ()
59 {
60   SCM stanza = get_property (this, "stanza");
61 
62   if (Text_interface::is_markup (stanza)
63       && !scm_is_eq (stanza, last_stanza_))
64     {
65       last_stanza_ = stanza;
66 
67       text_ = make_item ("StanzaNumber", SCM_EOL);
68       set_property (text_, "text", stanza);
69     }
70 }
71 
72 void
acknowledge_lyric_syllable(Grob_info inf)73 Stanza_number_engraver::acknowledge_lyric_syllable (Grob_info inf)
74 {
75   if (text_)
76     Side_position_interface::add_support (text_, inf.grob ());
77 }
78 
79 void
stop_translation_timestep()80 Stanza_number_engraver::stop_translation_timestep ()
81 {
82   text_ = 0;
83 }
84 
85 #include "translator.icc"
86 
87 void
boot()88 Stanza_number_engraver::boot ()
89 {
90   ADD_ACKNOWLEDGER (Stanza_number_engraver, lyric_syllable);
91 }
92 
93 ADD_TRANSLATOR (Stanza_number_engraver,
94                 /* doc */
95                 "Engrave stanza numbers.",
96 
97                 /* create */
98                 "StanzaNumber ",
99 
100                 /* read */
101                 "stanza ",
102 
103                 /* write */
104                 ""
105                );
106