lily/bar-number-engraver.cc

   1 /*
   2   bar-number-engraver.cc -- implement Bar_number_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c)  1997--2002 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7 */
   8
   9
  10 #include "lily-guile.hh"
  11 #include "paper-column.hh"
  12 #include "paper-def.hh"
  13 #include "side-position-interface.hh"
  14 #include "item.hh"
  15 #include "moment.hh"
  16 #include "engraver.hh"
  17 #include "translator-group.hh"
  18
  19 /*
  20
  21 TODO: detect the top staff (stavesFound), and acknowledge staff-group
  22 system-start-delims. If we find these, and the top staff is in the
  23 staff-group, add padding to the bar number.
  24
  25 */
  26
  27
  28 class Bar_number_engraver : public Engraver
  29 {
  30 protected:
  31   Item* text_;
  32 protected:
  33   virtual void stop_translation_timestep ();
  34   virtual void acknowledge_grob (Grob_info);
  35   virtual void process_music ();
  36   void create_items ();
  37   TRANSLATOR_DECLARATIONS(  Bar_number_engraver );
  38 };
  39
  40
  41 void
  42 Bar_number_engraver::process_music ()
  43 {
  44   // todo include (&&!time->cadenza_b_)
  45
  46   SCM wb = get_property ("whichBar");
  47
  48   if (gh_string_p (wb))
  49     {
  50       SCM smp = get_property ("measurePosition");
  51
  52       Moment mp = (unsmob_moment (smp)) ? *unsmob_moment (smp) : Moment (0);
  53       if (mp.main_part_ == Rational (0))
  54         {
  55           SCM bn = get_property ("currentBarNumber");
  56           SCM proc = get_property ("barNumberVisibility");
  57           if (gh_number_p (bn) && to_boolean(gh_call1(proc, bn)))
  58             {
  59               create_items ();
  60               // guh.
  61               text_->set_grob_property
  62                 ("text", scm_makfrom0str (to_string (gh_scm2int (bn)).to_str0 ()));
  63             }
  64         }
  65     }
  66
  67 }
  68
  69
  70
  71 Bar_number_engraver::Bar_number_engraver ()
  72 {
  73   text_ =0;
  74 }
  75
  76
  77 void
  78 Bar_number_engraver::acknowledge_grob (Grob_info inf)
  79 {
  80   Grob * s = inf.grob_;
  81   if (text_
  82       && dynamic_cast<Item*> (s)
  83       && s->get_grob_property ("break-align-symbol") == ly_symbol2scm ("left-edge"))
  84     {
  85       /*
  86         By default this would land on the Paper_column -- so why
  87         doesn't it work when you leave this out?  */
  88       text_->set_parent (s, X_AXIS);
  89     }
  90 }
  91
  92 void
  93 Bar_number_engraver::stop_translation_timestep ()
  94 {
  95   if (text_)
  96     {
  97       text_->set_grob_property ("side-support-elements", get_property ("stavesFound"));
  98       typeset_grob (text_);
  99       text_ =0;
 100     }
 101 }
 102
 103
 104 void
 105 Bar_number_engraver::create_items ()
 106 {
 107   if (text_)
 108     return;
 109
 110   SCM b = get_property ("BarNumber");
 111   text_ = new Item (b);
 112   Side_position_interface::set_axis (text_,Y_AXIS);
 113
 114   announce_grob(text_, SCM_EOL);
 115 }
 116
 117 ENTER_DESCRIPTION(Bar_number_engraver,
 118 /* descr */       "A bar number is created whenever measurePosition is zero. It is
 119 put on top of all staves, and appears only at  left side of the staff.",
 120 /* creats*/       "BarNumber",
 121 /* acks  */       "break-aligned-interface",
 122 /* reads */       "currentBarNumber stavesFound" ,
 123 /* write */       "");