lily/bar-number-engraver.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 1997--2010 Han-Wen Nienhuys <hanwen@xs4all.nl>
   5
   6   LilyPond is free software: you can redistribute it and/or modify
   7   it under the terms of the GNU General Public License as published by
   8   the Free Software Foundation, either version 3 of the License, or
   9   (at your option) any later version.
  10
  11   LilyPond is distributed in the hope that it will be useful,
  12   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14   GNU General Public License for more details.
  15
  16   You should have received a copy of the GNU General Public License
  17   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "paper-column.hh"
  21 #include "output-def.hh"
  22 #include "side-position-interface.hh"
  23 #include "engraver.hh"
  24 #include "context.hh"
  25 #include "grob-array.hh"
  26
  27 #include "translator.icc"
  28
  29 /*
  30   TODO: detect the top staff (stavesFound), and acknowledge staff-group
  31   system-start-delims. If we find these, and the top staff is in the
  32   staff-group, add padding to the bar number.
  33 */
  34 class Bar_number_engraver : public Engraver
  35 {
  36 protected:
  37   Item *text_;
  38 protected:
  39   void stop_translation_timestep ();
  40   DECLARE_ACKNOWLEDGER (break_alignment);
  41   void process_music ();
  42   void create_items ();
  43   TRANSLATOR_DECLARATIONS (Bar_number_engraver);
  44 };
  45
  46 void
  47 Bar_number_engraver::process_music ()
  48 {
  49   SCM wb = get_property ("whichBar");
  50
  51   if (scm_is_string (wb))
  52     {
  53       Moment mp (robust_scm2moment (get_property ("measurePosition"), Moment (0)));
  54       if (mp.main_part_ == Rational (0))
  55         {
  56           SCM bn = get_property ("currentBarNumber");
  57           SCM proc = get_property ("barNumberVisibility");
  58           if (scm_is_number (bn) && ly_is_procedure (proc)
  59               && to_boolean (scm_call_1 (proc, bn)))
  60             {
  61               create_items ();
  62               // guh.
  63               text_->set_property
  64                 ("text", scm_number_to_string (bn, scm_from_int (10)));
  65             }
  66         }
  67     }
  68 }
  69
  70 Bar_number_engraver::Bar_number_engraver ()
  71 {
  72   text_ = 0;
  73 }
  74
  75 void
  76 Bar_number_engraver::acknowledge_break_alignment (Grob_info inf)
  77 {
  78   Grob *s = inf.grob ();
  79   if (text_
  80       && dynamic_cast<Item *> (s))
  81     {
  82       text_->set_parent (s, X_AXIS);
  83     }
  84 }
  85
  86 void
  87 Bar_number_engraver::stop_translation_timestep ()
  88 {
  89   if (text_)
  90     {
  91       text_->set_object ("side-support-elements",
  92                          grob_list_to_grob_array (get_property ("stavesFound")));
  93       text_ = 0;
  94     }
  95 }
  96
  97 void
  98 Bar_number_engraver::create_items ()
  99 {
 100   if (text_)
 101     return;
 102
 103   text_ = make_item ("BarNumber", SCM_EOL);
 104 }
 105
 106
 107 ADD_ACKNOWLEDGER (Bar_number_engraver, break_alignment);
 108
 109 ADD_TRANSLATOR (Bar_number_engraver,
 110                 /* doc */
 111                 "A bar number is created whenever @code{measurePosition} is"
 112                 " zero and when there is a bar line (i.e., when"
 113                 " @code{whichBar} is set).  It is put on top of all staves,"
 114                 " and appears only at the left side of the staff.  The staves"
 115                 " are taken from @code{stavesFound}, which is maintained by"
 116                 " @ref{Staff_collecting_engraver}.",
 117
 118                 /* create */
 119                 "BarNumber ",
 120
 121                 /* read */
 122                 "currentBarNumber "
 123                 "whichBar "
 124                 "stavesFound "
 125                 "barNumberVisibility ",
 126
 127                 /* write */
 128                 ""
 129                 );