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@cs.uu.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   first_start_ = true;
  20   span_ = 0;
  21   span_events_[LEFT] = 0;
  22   span_events_[RIGHT] = 0;
  23 }
  24
  25 bool
  26 Staff_symbol_engraver::try_music (Music *music)
  27 {
  28   Direction d = to_dir (music->get_property ("span-direction"));
  29   if (d)
  30     {
  31       span_events_[d] = music;
  32       return true;
  33     }
  34
  35   return false;
  36 }
  37
  38 void
  39 Staff_symbol_engraver::process_music ()
  40 {
  41   if (span_events_[STOP])
  42     {
  43       finished_span_ = span_;
  44       span_ = 0;
  45     }
  46
  47   if (span_events_[START])
  48     start_spanner ();
  49 }
  50
  51
  52 void
  53 Staff_symbol_engraver::initialize ()
  54 {
  55   start_spanner ();
  56 }
  57
  58 void
  59 Staff_symbol_engraver::start_spanner ()
  60 {
  61   if (!span_)
  62     {
  63       span_ = make_spanner ("StaffSymbol", SCM_EOL);
  64     }
  65 }
  66
  67 void
  68 Staff_symbol_engraver::stop_spanner ()
  69 {
  70   if (finished_span_ && !finished_span_->get_bound (RIGHT))
  71     {
  72       finished_span_->set_bound (RIGHT, unsmob_grob (get_property ("currentCommandColumn")));
  73     }
  74   finished_span_ = 0;
  75 }
  76
  77 void
  78 Staff_symbol_engraver::stop_translation_timestep ()
  79 {
  80   if ((span_events_[START] || first_start_)
  81       && span_
  82       && !span_->get_bound (LEFT))
  83     {
  84       span_->set_bound (LEFT, unsmob_grob (get_property ("currentCommandColumn")));
  85       first_start_ = false;
  86     }
  87
  88   span_events_[START] = 0;
  89   span_events_[STOP] = 0;
  90   stop_spanner ();
  91 }
  92
  93 void
  94 Staff_symbol_engraver::finalize ()
  95 {
  96   finished_span_ = span_;
  97   span_ = 0;
  98   stop_spanner ();
  99 }
 100
 101 void
 102 Staff_symbol_engraver::acknowledge_grob (Grob_info s)
 103 {
 104
 105   /*
 106     Perhaps should try to take SeparationItem as bound of the staff
 107     symbol?
 108    */
 109   if (span_)
 110     s.grob_->set_property ("staff-symbol", span_->self_scm ());
 111 }
 112
 113 ADD_TRANSLATOR (Staff_symbol_engraver,
 114                 /* descr */ "Create the constellation of five (default) "
 115                 "staff lines.",
 116                 /* creats*/ "StaffSymbol",
 117                 /* accepts */ "staff-span-event",
 118                 /* acks  */ "grob-interface",
 119                 /* reads */ "",
 120                 /* write */ "");