lily/repeat-acknowledge-engraver.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 2000--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 "engraver.hh"
  21 #include "translator-group.hh"
  22 #include "context.hh"
  23 #include "repeated-music.hh"
  24
  25 #include "translator.icc"
  26
  27 /*
  28   Objective:
  29
  30   -- set and reset repeatCommands, so Unfolded_repeat_iterator knows
  31   where to set variables.
  32
  33   -- collect information passed by Unfolded_repeat_iterator for
  34   Bar_engraver: writes whichBar property. (TODO: check for
  35   interactions with timing engraver.)
  36 */
  37 class Repeat_acknowledge_engraver : public Engraver
  38 {
  39 public:
  40
  41   TRANSLATOR_DECLARATIONS (Repeat_acknowledge_engraver);
  42 protected:
  43   void start_translation_timestep ();
  44   void process_music ();
  45   virtual void initialize ();
  46 };
  47
  48 void
  49 Repeat_acknowledge_engraver::initialize ()
  50 {
  51   context ()->set_property ("repeatCommands", SCM_EOL);
  52 }
  53
  54 Repeat_acknowledge_engraver::Repeat_acknowledge_engraver ()
  55 {
  56 }
  57
  58 void
  59 Repeat_acknowledge_engraver::start_translation_timestep ()
  60 {
  61   SCM rc;
  62   Context *tr = context ()->where_defined (ly_symbol2scm ("repeatCommands"), &rc);
  63   if (!tr)
  64     tr = context ();
  65
  66   tr->set_property ("repeatCommands", SCM_EOL);
  67 }
  68
  69 void
  70 Repeat_acknowledge_engraver::process_music ()
  71 {
  72   /*
  73     At the start of a piece, we don't print any repeat bars.
  74   */
  75   if (!now_mom ().main_part_)
  76     return;
  77
  78   SCM cs = get_property ("repeatCommands");
  79
  80   string s = "";
  81   bool start = false;
  82   bool end = false;
  83   bool volta_found = false;
  84   while (scm_is_pair (cs))
  85     {
  86       SCM command = scm_car (cs);
  87       if (command == ly_symbol2scm ("start-repeat"))
  88         start = true;
  89       else if (command == ly_symbol2scm ("end-repeat"))
  90         end = true;
  91       else if (scm_is_pair (command) && scm_car (command) == ly_symbol2scm ("volta"))
  92         volta_found = true;
  93       cs = scm_cdr (cs);
  94     }
  95
  96   if (start && end)
  97     s = robust_scm2string (get_property ("doubleRepeatType"), ":|:");
  98   else if (start)
  99     s = "|:";
 100   else if (end)
 101     s = ":|";
 102
 103   /*
 104     TODO: line breaks might be allowed if we set whichBar to "".
 105   */
 106
 107   /*
 108     We only set the barline if we wouldn't overwrite a previously set
 109     barline.
 110   */
 111   SCM wb = get_property ("whichBar");
 112   SCM db = get_property ("defaultBarType");
 113   if (!scm_is_string (wb) || ly_is_equal (db, wb))
 114     {
 115       if (s != "" || (volta_found && !scm_is_string (wb)))
 116         context ()->set_property ("whichBar", ly_string2scm (s));
 117     }
 118 }
 119
 120 ADD_TRANSLATOR (Repeat_acknowledge_engraver,
 121                 /* doc */
 122                 "Acknowledge repeated music, and convert the contents of"
 123                 " @code{repeatCommands} into an appropriate setting for"
 124                 " @code{whichBar}.",
 125
 126                 /* create */
 127                 "",
 128
 129                 /* read */
 130                 "doubleRepeatType "
 131                 "repeatCommands "
 132                 "whichBar ",
 133
 134                 /* write */
 135                 ""
 136                 );