lily/trill-spanner-engraver.cc

   1 /*
   2   trill-spanner-engraver.cc -- implement Trill_spanner_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2000--2005 Jan Nieuwenhuizen <janneke@gnu.org>
   7 */
   8
   9 /*
  10   C&P from text-spanner.cc
  11
  12   - todo: ending should be detected automatically? a new note
  13   automatically is the end of the trill?
  14 */
  15
  16 #include "note-column.hh"
  17 #include "side-position-interface.hh"
  18 #include "engraver.hh"
  19
  20 #include "translator.icc"
  21
  22 class Trill_spanner_engraver : public Engraver
  23 {
  24 public:
  25   TRANSLATOR_DECLARATIONS (Trill_spanner_engraver);
  26 protected:
  27   virtual void finalize ();
  28   DECLARE_ACKNOWLEDGER (note_column);
  29   virtual bool try_music (Music *);
  30   void stop_translation_timestep ();
  31   void process_music ();
  32
  33 private:
  34   Spanner *span_;
  35   Spanner *finished_;
  36   Music *current_event_;
  37   Drul_array<Music *> event_drul_;
  38   void typeset_all ();
  39 };
  40
  41 Trill_spanner_engraver::Trill_spanner_engraver ()
  42 {
  43   finished_ = 0;
  44   current_event_ = 0;
  45   span_ = 0;
  46   event_drul_[START] = 0;
  47   event_drul_[STOP] = 0;
  48 }
  49
  50 bool
  51 Trill_spanner_engraver::try_music (Music *m)
  52 {
  53   if (m->is_mus_type ("trill-span-event"))
  54     {
  55       Direction d = to_dir (m->get_property ("span-direction"));
  56       event_drul_[d] = m;
  57       return true;
  58     }
  59
  60   return false;
  61 }
  62
  63 void
  64 Trill_spanner_engraver::process_music ()
  65 {
  66   if (event_drul_[STOP])
  67     {
  68       if (!span_)
  69         event_drul_[STOP]->origin ()->warning (_ ("can't find start of trill spanner"));
  70       else
  71         {
  72           finished_ = span_;
  73           span_ = 0;
  74           current_event_ = 0;
  75         }
  76     }
  77
  78   if (event_drul_[START])
  79     {
  80       if (current_event_)
  81         event_drul_[START]->origin ()->warning (_ ("already have a trill spanner"));
  82       else
  83         {
  84           current_event_ = event_drul_[START];
  85           span_ = make_spanner ("TrillSpanner", event_drul_[START]->self_scm ());
  86           Side_position_interface::set_axis (span_, Y_AXIS);
  87           event_drul_[START] = 0;
  88         }
  89     }
  90 }
  91
  92 void
  93 Trill_spanner_engraver::acknowledge_note_column (Grob_info info)
  94 {
  95   Spanner *spans[2] ={span_, finished_};
  96   for (int i = 0; i < 2; i++)
  97     {
  98       if (spans[i])
  99         {
 100           Side_position_interface::add_support (spans[i], info.grob ());
 101           add_bound_item (spans[i], dynamic_cast<Item *> (info.grob ()));
 102         }
 103     }
 104 }
 105
 106 void
 107 Trill_spanner_engraver::typeset_all ()
 108 {
 109   if (finished_)
 110     {
 111       if (!finished_->get_bound (RIGHT))
 112         {
 113           Grob *e = unsmob_grob (get_property ("currentMusicalColumn"));
 114           finished_->set_bound (RIGHT, e);
 115         }
 116       finished_ = 0;
 117     }
 118 }
 119
 120 void
 121 Trill_spanner_engraver::stop_translation_timestep ()
 122 {
 123   if (span_ && !span_->get_bound (LEFT))
 124     {
 125       Grob *e = unsmob_grob (get_property ("currentMusicalColumn"));
 126       span_->set_bound (LEFT, e);
 127     }
 128
 129   typeset_all ();
 130   event_drul_[START] = 0;
 131   event_drul_[STOP] = 0;
 132 }
 133
 134 void
 135 Trill_spanner_engraver::finalize ()
 136 {
 137   typeset_all ();
 138   if (span_)
 139     {
 140       current_event_->origin ()->warning (_ ("unterminated trill spanner"));
 141       span_->suicide ();
 142       span_ = 0;
 143     }
 144 }
 145 ADD_ACKNOWLEDGER (Trill_spanner_engraver, note_column);
 146 ADD_TRANSLATOR (Trill_spanner_engraver,
 147                 /* doc */ "Create trill spanner from a Music.",
 148                 /* create */ "TrillSpanner",
 149                 /* accept */ "trill-span-event",
 150                 /* read */ "",
 151                 /* write */ "");