lily/figured-bass-engraver.cc

   1 /*
   2 figured-bass-engraver.cc --  implement Figured_bass_engraver
   3
   4 source file of the GNU LilyPond music typesetter
   5
   6 (c) 2002--2004 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7
   8  */
   9
  10 #include "engraver.hh"
  11 #include "text-item.hh"
  12 #include "event.hh"
  13 #include "item.hh"
  14 #include "context.hh"
  15
  16 class Figured_bass_engraver : public Engraver
  17 {
  18   TRANSLATOR_DECLARATIONS (Figured_bass_engraver);
  19 protected:
  20   Link_array<Music> figures_;
  21   Music * rest_req_;
  22
  23   Grob * figure_;
  24
  25   virtual bool try_music (Music*);
  26   virtual void stop_translation_timestep ();
  27   virtual void process_music ();
  28 };
  29
  30
  31 Figured_bass_engraver::Figured_bass_engraver ()
  32 {
  33   figure_ = 0;
  34   rest_req_ = 0;
  35 }
  36
  37 void
  38 Figured_bass_engraver::stop_translation_timestep ()
  39 {
  40   if (figure_)
  41     {
  42       typeset_grob (figure_);
  43       figure_ = 0;
  44     }
  45
  46   figures_.clear ();
  47   rest_req_ = 0;
  48 }
  49
  50 bool
  51 Figured_bass_engraver::try_music (Music*m)
  52 {
  53   if (m->is_mus_type ("bass-figure-event"))
  54     {
  55       figures_.push (m);
  56       return true;
  57     }
  58   else if (m->is_mus_type ("rest-event"))
  59     {
  60       rest_req_ = m;
  61       return true;
  62     }
  63   return false;
  64 }
  65
  66 void
  67 Figured_bass_engraver::process_music ()
  68 {
  69   if (rest_req_)
  70     {
  71       figure_ = make_item ("BassFigure");
  72       announce_grob (figure_, rest_req_->self_scm ()); // todo
  73       figure_->set_property ("text" , scm_makfrom0str ("-"));
  74     }
  75   else if (figures_.size ())
  76     {
  77       SCM proc = get_property ("bassFigureFormatFunction");
  78       if (ly_procedure_p (proc))
  79         {
  80           SCM l = SCM_EOL;
  81           SCM * t = &l;
  82           for (int i = 0; i < figures_.size (); i++)
  83             {
  84               *t = scm_cons (figures_[i]->self_scm (), SCM_EOL);
  85               t = SCM_CDRLOC (*t);
  86             }
  87           figure_ = make_item ("BassFigure");
  88           scm_call_3 (proc, l, daddy_context_->self_scm (),
  89                       figure_->self_scm ());
  90           announce_grob (figure_, figures_[0]->self_scm ()); // todo
  91         }
  92     }
  93 }
  94
  95
  96 ENTER_DESCRIPTION (Figured_bass_engraver,
  97 /* descr */       "Make figured bass numbers.",
  98 /* creats*/       "BassFigure",
  99 /* accepts */     "rest-event bass-figure-event",
 100 /* acks  */      "",
 101 /* reads */       "bassFigureFormatFunction",
 102 /* write */       "");