lily/metronome-engraver.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 1998--2010 Jan Nieuwenhuizen <janneke@gnu.org>
   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 <cctype>
  21 using namespace std;
  22
  23 #include "engraver.hh"
  24
  25 #include "context.hh"
  26 #include "duration.hh"
  27 #include "grob-array.hh"
  28 #include "item.hh"
  29 #include "stream-event.hh"
  30 #include "text-interface.hh"
  31
  32 #include "translator.icc"
  33
  34 class Metronome_mark_engraver : public Engraver
  35 {
  36 public:
  37   TRANSLATOR_DECLARATIONS (Metronome_mark_engraver);
  38 protected:
  39   Item *text_;
  40   Grob *bar_line_;
  41
  42   SCM last_duration_;
  43   SCM last_count_;
  44   SCM last_text_;
  45
  46 protected:
  47   virtual void derived_mark () const;
  48   void stop_translation_timestep ();
  49   void process_music ();
  50 };
  51
  52 Metronome_mark_engraver::Metronome_mark_engraver ()
  53 {
  54   text_ = 0;
  55   last_duration_ = SCM_EOL;
  56   last_count_ = SCM_EOL;
  57   last_text_ = SCM_EOL;
  58 }
  59
  60 void
  61 Metronome_mark_engraver::derived_mark () const
  62 {
  63   scm_gc_mark (last_count_);
  64   scm_gc_mark (last_duration_);
  65   scm_gc_mark (last_text_);
  66 }
  67
  68 void
  69 Metronome_mark_engraver::stop_translation_timestep ()
  70 {
  71   if (text_)
  72     {
  73       Grob *mc = unsmob_grob (get_property ("currentMusicalColumn"));
  74       text_->set_parent (mc, X_AXIS);
  75       text_->set_object ("side-support-elements",
  76                          grob_list_to_grob_array (get_property ("stavesFound")));
  77       text_ = 0;
  78     }
  79 }
  80
  81 void
  82 Metronome_mark_engraver::process_music ()
  83 {
  84   SCM count = get_property ("tempoUnitCount");
  85   SCM duration = get_property ("tempoUnitDuration");
  86   SCM text = get_property ("tempoText");
  87
  88   if ( ( (unsmob_duration (duration) && scm_is_number (count))
  89         || Text_interface::is_markup (text) )
  90       && !(ly_is_equal (count, last_count_)
  91            && ly_is_equal (duration, last_duration_)
  92            && ly_is_equal (text, last_text_)))
  93     {
  94       text_ = make_item ("MetronomeMark", SCM_EOL);
  95
  96       SCM proc = get_property ("metronomeMarkFormatter");
  97       SCM result = scm_call_4 (proc,
  98                                text,
  99                                duration,
 100                                count,
 101                                context ()->self_scm ());
 102
 103       text_->set_property ("text", result);
 104     }
 105
 106   last_duration_ = duration;
 107   last_count_ = count;
 108   last_text_ = text;
 109 }
 110
 111 ADD_TRANSLATOR (Metronome_mark_engraver,
 112                 /* doc */
 113                 "Engrave metronome marking.  This delegates the formatting"
 114                 " work to the function in the @code{metronomeMarkFormatter}"
 115                 " property.  The mark is put over all staves.  The staves are"
 116                 " taken from the @code{stavesFound} property, which is"
 117                 " maintained by @ref{Staff_collecting_engraver}.",
 118
 119                 /* create */
 120                 "MetronomeMark ",
 121
 122                 /* read */
 123                 "stavesFound "
 124                 "metronomeMarkFormatter "
 125                 "tempoUnitDuration "
 126                 "tempoUnitCount "
 127                 "tempoText "
 128                 "tempoHideNote ",
 129
 130                 /* write */
 131                 ""
 132                 );