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--2009 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7 */
   8
   9 #include "paper-column.hh"
  10 #include "output-def.hh"
  11 #include "side-position-interface.hh"
  12 #include "engraver.hh"
  13 #include "context.hh"
  14 #include "grob-array.hh"
  15
  16 #include "translator.icc"
  17
  18 /*
  19   TODO: detect the top staff (stavesFound), and acknowledge staff-group
  20   system-start-delims. If we find these, and the top staff is in the
  21   staff-group, add padding to the bar number.
  22 */
  23 class Bar_number_engraver : public Engraver
  24 {
  25 protected:
  26   Item *text_;
  27 protected:
  28   void stop_translation_timestep ();
  29   DECLARE_ACKNOWLEDGER (break_aligned);
  30   DECLARE_ACKNOWLEDGER (break_alignment);
  31   void process_music ();
  32   void create_items ();
  33   TRANSLATOR_DECLARATIONS (Bar_number_engraver);
  34 };
  35
  36 void
  37 Bar_number_engraver::process_music ()
  38 {
  39   SCM wb = get_property ("whichBar");
  40
  41   if (scm_is_string (wb))
  42     {
  43       Moment mp (robust_scm2moment (get_property ("measurePosition"), Moment (0)));
  44       if (mp.main_part_ == Rational (0))
  45         {
  46           SCM bn = get_property ("currentBarNumber");
  47           SCM proc = get_property ("barNumberVisibility");
  48           if (scm_is_number (bn) && ly_is_procedure (proc)
  49               && to_boolean (scm_call_1 (proc, bn)))
  50             {
  51               create_items ();
  52               // guh.
  53               text_->set_property
  54                 ("text", scm_number_to_string (bn, scm_from_int (10)));
  55             }
  56         }
  57     }
  58 }
  59
  60 Bar_number_engraver::Bar_number_engraver ()
  61 {
  62   text_ = 0;
  63 }
  64
  65
  66 /*
  67   see rehearsal mark comments.
  68  */
  69 void
  70 Bar_number_engraver::acknowledge_break_aligned (Grob_info inf)
  71 {
  72   Grob *s = inf.grob ();
  73   if (text_
  74       && !text_->get_parent (X_AXIS)
  75       && dynamic_cast<Item *> (s)
  76       && (s->get_property_data ("break-align-symbol")
  77           == text_->get_property_data ("break-align-symbol")))
  78     {
  79       /*
  80         By default this would land on the Paper_column -- so why
  81         doesn't it work when you leave this out?  */
  82       text_->set_parent (s, X_AXIS);
  83     }
  84 }
  85
  86
  87 void
  88 Bar_number_engraver::acknowledge_break_alignment (Grob_info inf)
  89 {
  90   Grob *s = inf.grob ();
  91   if (text_
  92       && dynamic_cast<Item *> (s))
  93     {
  94       text_->set_parent (s, X_AXIS);
  95     }
  96 }
  97
  98 void
  99 Bar_number_engraver::stop_translation_timestep ()
 100 {
 101   if (text_)
 102     {
 103       text_->set_object ("side-support-elements",
 104                          grob_list_to_grob_array (get_property ("stavesFound")));
 105       text_ = 0;
 106     }
 107 }
 108
 109 void
 110 Bar_number_engraver::create_items ()
 111 {
 112   if (text_)
 113     return;
 114
 115   text_ = make_item ("BarNumber", SCM_EOL);
 116 }
 117
 118
 119 ADD_ACKNOWLEDGER (Bar_number_engraver, break_aligned);
 120 ADD_ACKNOWLEDGER (Bar_number_engraver, break_alignment);
 121
 122 ADD_TRANSLATOR (Bar_number_engraver,
 123                 /* doc */
 124                 "A bar number is created whenever @code{measurePosition} is"
 125                 " zero and when there is a bar line (i.e., when"
 126                 " @code{whichBar} is set).  It is put on top of all staves,"
 127                 " and appears only at the left side of the staff.  The staves"
 128                 " are taken from @code{stavesFound}, which is maintained by"
 129                 " @ref{Staff_collecting_engraver}.",
 130
 131                 /* create */
 132                 "BarNumber ",
 133
 134                 /* read */
 135                 "currentBarNumber "
 136                 "whichBar "
 137                 "stavesFound "
 138                 "barNumberVisibility ",
 139
 140                 /* write */
 141                 ""
 142                 );