lily/span-bar-engraver.cc

   1 /*
   2   span-bar-grav.cc -- implement Span_bar_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c)  1997--2003 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7 */
   8
   9
  10 #include "lily-guile.hh"
  11 #include "bar-line.hh"
  12 #include "item.hh"
  13 #include "span-bar.hh"
  14 #include "engraver.hh"
  15
  16
  17 /**
  18
  19   Make bars that span multiple "staves". Catch bars, and span a
  20   Span_bar over them if we find more than 2 bars.  Vertical alignment
  21   of staves changes the appearance of spanbars.  It is up to the
  22   aligner (Vertical_align_engraver, in this case, to add extra
  23   dependencies to the spanbars.
  24
  25   */
  26 class Span_bar_engraver : public Engraver
  27 {
  28   Item * spanbar_;
  29   Link_array<Item> bars_;
  30
  31 public:
  32   TRANSLATOR_DECLARATIONS(Span_bar_engraver);
  33 protected:
  34   virtual void acknowledge_grob (Grob_info);
  35   virtual void stop_translation_timestep ();
  36
  37 };
  38
  39
  40 Span_bar_engraver::Span_bar_engraver ()
  41 {
  42   spanbar_ =0;
  43 }
  44
  45
  46
  47 void
  48 Span_bar_engraver::acknowledge_grob (Grob_info i)
  49 {
  50   int depth = i.origin_transes (this).size ();
  51   if (depth > 1
  52       && Bar_line::has_interface (i.grob_))
  53     {
  54       Item * it = dynamic_cast<Item*> (i.grob_);
  55       bars_.push (it);
  56
  57       if (bars_.size () >= 2 && !spanbar_)
  58         {
  59           spanbar_ = new Item (get_property ("SpanBar"));
  60
  61           spanbar_->set_parent (bars_[0], X_AXIS);
  62
  63           announce_grob (spanbar_, SCM_EOL);
  64         }
  65     }
  66 }
  67 void
  68 Span_bar_engraver::stop_translation_timestep ()
  69 {
  70   if (spanbar_)
  71     {
  72       for (int i=0; i < bars_.size () ; i++)
  73         Span_bar::add_bar (spanbar_,bars_[i]);
  74
  75       SCM vissym =ly_symbol2scm ("break-visibility");
  76       SCM vis = bars_[0]->internal_get_grob_property (vissym);
  77       if (scm_equal_p (spanbar_->internal_get_grob_property (vissym), vis) != SCM_BOOL_T)
  78         spanbar_->internal_set_grob_property (vissym, vis);
  79
  80       typeset_grob (spanbar_);
  81       spanbar_ =0;
  82     }
  83   bars_.set_size (0);
  84 }
  85
  86
  87
  88
  89
  90
  91
  92 ENTER_DESCRIPTION(Span_bar_engraver,
  93 /* descr */       "This engraver makes cross-staff barlines: It catches all normal "
  94 "bar lines, and draws a single span-bar across them.",
  95 /* creats*/       "SpanBar",
  96 /* accepts */     "",
  97 /* acks  */      "bar-line-interface",
  98 /* reads */       "",
  99 /* write */       "");