lily/staff-symbol-engraver.cc

   1 /*
   2   staff-symbol-engraver.cc -- implement Staff_symbol_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1997--2005 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7 */
   8
   9 #include "staff-symbol-engraver.hh"
  10 #include "spanner.hh"
  11
  12 Staff_symbol_engraver::~Staff_symbol_engraver ()
  13 {
  14   assert (!span_);
  15 }
  16
  17 Staff_symbol_engraver::Staff_symbol_engraver ()
  18 {
  19   finished_span_ = 0;
  20   first_start_ = true;
  21   span_ = 0;
  22   span_events_[LEFT] = 0;
  23   span_events_[RIGHT] = 0;
  24 }
  25
  26 bool
  27 Staff_symbol_engraver::try_music (Music *music)
  28 {
  29   Direction d = to_dir (music->get_property ("span-direction"));
  30   if (d)
  31     {
  32       span_events_[d] = music;
  33       return true;
  34     }
  35
  36   return false;
  37 }
  38
  39 void
  40 Staff_symbol_engraver::process_music ()
  41 {
  42   if (span_events_[STOP])
  43     {
  44       finished_span_ = span_;
  45       span_ = 0;
  46     }
  47
  48   if (span_events_[START]
  49       || (first_start_ && !span_events_[STOP]))
  50     start_spanner ();
  51 }
  52
  53 void
  54 Staff_symbol_engraver::start_spanner ()
  55 {
  56   if (!span_)
  57     span_ = make_spanner ("StaffSymbol", SCM_EOL);
  58 }
  59
  60 void
  61 Staff_symbol_engraver::stop_spanner ()
  62 {
  63   if (finished_span_ && !finished_span_->get_bound (RIGHT))
  64     finished_span_->set_bound (RIGHT, unsmob_grob (get_property ("currentCommandColumn")));
  65   finished_span_ = 0;
  66 }
  67
  68 void
  69 Staff_symbol_engraver::stop_translation_timestep ()
  70 {
  71   if ((span_events_[START] || first_start_)
  72       && span_
  73       && !span_->get_bound (LEFT))
  74     {
  75       span_->set_bound (LEFT, unsmob_grob (get_property ("currentCommandColumn")));
  76       first_start_ = false;
  77     }
  78
  79   span_events_[START] = 0;
  80   span_events_[STOP] = 0;
  81   stop_spanner ();
  82 }
  83
  84 void
  85 Staff_symbol_engraver::finalize ()
  86 {
  87   finished_span_ = span_;
  88   span_ = 0;
  89   stop_spanner ();
  90 }
  91
  92 /*
  93   Todo: staff-symbol-referencer iface.
  94 */
  95 void
  96 Staff_symbol_engraver::acknowledge_grob (Grob_info s)
  97 {
  98   /*
  99     Perhaps should try to take SeparationItem as bound of the staff
 100     symbol?
 101   */
 102   if (span_ || finished_span_)
 103     {
 104       Spanner *my = span_ ? span_ : finished_span_;
 105       s.grob ()->set_object ("staff-symbol", my->self_scm ());
 106     }
 107 }
 108
 109 #include "translator.icc"
 110 ADD_ACKNOWLEDGER (Staff_symbol_engraver, grob);
 111 ADD_TRANSLATOR (Staff_symbol_engraver,
 112                 /* doc */ "Create the constellation of five (default) "
 113                 "staff lines.",
 114                 /* create */ "StaffSymbol",
 115                 /* accept */ "staff-span-event",
 116                 /* read */ "",
 117                 /* write */ "");