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--2003 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) && gh_procedure_p (proc)
  58               && to_boolean(gh_call1(proc, bn)))
  59             {
  60               create_items ();
  61               // guh.
  62               text_->set_grob_property
  63                 ("text", scm_makfrom0str (to_string (gh_scm2int (bn)).to_str0 ()));
  64             }
  65         }
  66     }
  67
  68 }
  69
  70
  71
  72 Bar_number_engraver::Bar_number_engraver ()
  73 {
  74   text_ =0;
  75 }
  76
  77
  78 void
  79 Bar_number_engraver::acknowledge_grob (Grob_info inf)
  80 {
  81   Grob * s = inf.grob_;
  82   if (text_
  83       && dynamic_cast<Item*> (s)
  84       && s->get_grob_property ("break-align-symbol") == ly_symbol2scm ("left-edge"))
  85     {
  86       /*
  87         By default this would land on the Paper_column -- so why
  88         doesn't it work when you leave this out?  */
  89       text_->set_parent (s, X_AXIS);
  90     }
  91 }
  92
  93 void
  94 Bar_number_engraver::stop_translation_timestep ()
  95 {
  96   if (text_)
  97     {
  98       text_->set_grob_property ("side-support-elements", get_property ("stavesFound"));
  99       typeset_grob (text_);
 100       text_ =0;
 101     }
 102 }
 103
 104
 105 void
 106 Bar_number_engraver::create_items ()
 107 {
 108   if (text_)
 109     return;
 110
 111   SCM b = get_property ("BarNumber");
 112   text_ = new Item (b);
 113   Side_position_interface::set_axis (text_,Y_AXIS);
 114
 115   announce_grob(text_, SCM_EOL);
 116 }
 117
 118 ENTER_DESCRIPTION(Bar_number_engraver,
 119 /* descr */       "A bar number is created whenever measurePosition is zero. It is\n"
 120 "put on top of all staves, and appears only at  left side of the staff.",
 121 /* creats*/       "BarNumber",
 122 /* accepts */     "",
 123 /* acks  */      "break-aligned-interface",
 124 /* reads */       "currentBarNumber stavesFound barNumberVisibility" ,
 125 /* write */       "");