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   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     start_spanner ();
  50 }
  51
  52
  53 void
  54 Staff_symbol_engraver::initialize ()
  55 {
  56   start_spanner ();
  57 }
  58
  59 void
  60 Staff_symbol_engraver::start_spanner ()
  61 {
  62   if (!span_)
  63     {
  64       span_ = make_spanner ("StaffSymbol", SCM_EOL);
  65     }
  66 }
  67
  68 void
  69 Staff_symbol_engraver::stop_spanner ()
  70 {
  71   if (finished_span_ && !finished_span_->get_bound (RIGHT))
  72     {
  73       finished_span_->set_bound (RIGHT, unsmob_grob (get_property ("currentCommandColumn")));
  74     }
  75   finished_span_ = 0;
  76 }
  77
  78 void
  79 Staff_symbol_engraver::stop_translation_timestep ()
  80 {
  81   if ((span_events_[START] || first_start_)
  82       && span_
  83       && !span_->get_bound (LEFT))
  84     {
  85       span_->set_bound (LEFT, unsmob_grob (get_property ("currentCommandColumn")));
  86       first_start_ = false;
  87     }
  88
  89   span_events_[START] = 0;
  90   span_events_[STOP] = 0;
  91   stop_spanner ();
  92 }
  93
  94 void
  95 Staff_symbol_engraver::finalize ()
  96 {
  97   finished_span_ = span_;
  98   span_ = 0;
  99   stop_spanner ();
 100 }
 101
 102 void
 103 Staff_symbol_engraver::acknowledge_grob (Grob_info s)
 104 {
 105
 106   /*
 107     Perhaps should try to take SeparationItem as bound of the staff
 108     symbol?
 109    */
 110   if (span_)
 111     s.grob_->set_property ("staff-symbol", span_->self_scm ());
 112 }
 113
 114 ADD_TRANSLATOR (Staff_symbol_engraver,
 115                 /* descr */ "Create the constellation of five (default) "
 116                 "staff lines.",
 117                 /* creats*/ "StaffSymbol",
 118                 /* accepts */ "staff-span-event",
 119                 /* acks  */ "grob-interface",
 120                 /* reads */ "",
 121                 /* write */ "");