]> git.donarmstrong.com Git - lilypond.git/blob - lily/extender-engraver.cc
release: 1.3.56
[lilypond.git] / lily / extender-engraver.cc
1 /*
2   extender-engraver.cc -- implement Extender_engraver
3
4   (c) 1999 Glen Prideaux <glenprideaux@iname.com>,
5   Han-Wen Nienhuys, Jan Nieuwenhuizen.
6   
7 */
8
9 #include "proto.hh"
10 #include "musical-request.hh"
11 #include "extender-spanner.hh"
12 #include "paper-column.hh"
13 #include "text-item.hh"
14 #include "engraver.hh"
15 #include "drul-array.hh"
16 #include "extender-spanner.hh"
17 #include "pqueue.hh"
18
19
20 /**
21   Generate an centred extender.  Should make a Extender_spanner that
22   typesets a nice centred extender of varying length depending on the
23   gap between syllables.
24
25   We remember the last Text_item that come across. When we get a
26   request, we create the spanner, and attach the left point to the
27   last lyrics, and the right point to any lyrics we receive by
28   then.  */
29 class Extender_engraver : public Engraver
30 {
31   Text_item *  last_lyric_l_;
32   Text_item * current_lyric_l_;
33   Extender_req* req_l_;
34   Lyric_extender* extender_spanner_p_;
35 public:
36   Extender_engraver ();
37   VIRTUAL_COPY_CONS (Translator);
38
39 protected:
40   virtual void acknowledge_element (Score_element_info);
41   virtual void do_removal_processing();
42   virtual void do_process_music();
43   virtual bool do_try_music (Music*);
44   virtual void do_pre_move_processing();
45   virtual void do_post_move_processing ();
46 private:
47
48 };
49
50
51 ADD_THIS_TRANSLATOR (Extender_engraver);
52
53 Extender_engraver::Extender_engraver ()
54 {
55   current_lyric_l_ = 0;
56   last_lyric_l_ = 0;
57   extender_spanner_p_ = 0;
58   req_l_ = 0;
59 }
60
61 void
62 Extender_engraver::acknowledge_element (Score_element_info i)
63 {
64   if (Text_item* t = dynamic_cast<Text_item*> (i.elem_l_))
65     {
66       current_lyric_l_ = t;
67       if (extender_spanner_p_
68           && !extender_spanner_p_->get_bound (RIGHT)
69             )
70           {
71             extender_spanner_p_->set_textitem (RIGHT, t);
72           }
73     }
74 }
75
76
77 bool
78 Extender_engraver::do_try_music (Music* r)
79 {
80   if (Extender_req* p = dynamic_cast <Extender_req *> (r))
81     {
82       if (req_l_)
83         return false;
84
85       req_l_ = p;
86       return true;
87     }
88   return false;
89 }
90
91 void
92 Extender_engraver::do_removal_processing ()
93 {
94   if (extender_spanner_p_)
95     {
96       req_l_->warning (_ ("unterminated extender"));
97       extender_spanner_p_->set_bound(RIGHT, get_staff_info ().command_pcol_l ());
98     }
99 }
100
101 void
102 Extender_engraver::do_process_music ()
103 {
104   if (req_l_)
105     {
106       if (!last_lyric_l_)
107         {
108           req_l_->warning (_ ("Nothing to connect extender to on the left.  Ignoring extender request."));
109           return;
110         }
111       
112       extender_spanner_p_ = new Lyric_extender (get_property ("basicLyricExtenderProperties"));
113       extender_spanner_p_->set_textitem  (LEFT, last_lyric_l_);
114       announce_element (Score_element_info (extender_spanner_p_, req_l_));
115     }
116 }
117
118
119 void
120 Extender_engraver::do_pre_move_processing ()
121 {
122   if (extender_spanner_p_)
123     {
124       typeset_element (extender_spanner_p_);
125       extender_spanner_p_ = 0;
126     }
127
128   if (current_lyric_l_)
129     {
130       last_lyric_l_ = current_lyric_l_;
131       current_lyric_l_ =0;
132     }
133 }
134
135 void
136 Extender_engraver::do_post_move_processing ()
137 {
138   req_l_ = 0;
139 }
140
141