lily/volta-repeat-iterator.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 2002--2015 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 "music.hh"
  21 #include "sequential-iterator.hh"
  22 #include "context.hh"
  23
  24 class Volta_repeat_iterator : public Sequential_iterator
  25 {
  26 public:
  27   DECLARE_SCHEME_CALLBACK (constructor, ());
  28   Volta_repeat_iterator ();
  29
  30   void add_repeat_command (SCM);
  31 protected:
  32   virtual SCM get_music_list () const;
  33   virtual void next_element (bool);
  34   virtual void construct_children ();
  35   virtual void process (Moment);
  36   virtual void derived_mark () const;
  37
  38   bool first_time_;
  39   int alt_count_;
  40   int rep_count_;
  41   int done_count_;
  42   SCM alt_restores_;
  43 };
  44
  45 Volta_repeat_iterator::Volta_repeat_iterator ()
  46 {
  47   done_count_ = alt_count_ = rep_count_ = 0;
  48   first_time_ = true;
  49   alt_restores_ = SCM_EOL;
  50 }
  51
  52 void
  53 Volta_repeat_iterator::derived_mark () const
  54 {
  55   scm_gc_mark (alt_restores_);
  56   Sequential_iterator::derived_mark ();
  57 }
  58
  59 SCM
  60 Volta_repeat_iterator::get_music_list ()const
  61 {
  62   return scm_cons (get_music ()->get_property ("element"),
  63                    Sequential_iterator::get_music_list ());
  64 }
  65
  66 void
  67 Volta_repeat_iterator::construct_children ()
  68 {
  69   Sequential_iterator::construct_children ();
  70
  71   SCM alts = get_music ()->get_property ("elements");
  72
  73   alt_count_ = int (scm_ilength (alts));
  74   rep_count_ = scm_to_int (get_music ()->get_property ("repeat-count"));
  75   done_count_ = 0;
  76 }
  77
  78 /*
  79   TODO: add source information for debugging
  80 */
  81 void
  82 Volta_repeat_iterator::add_repeat_command (SCM what)
  83 {
  84   SCM reps = ly_symbol2scm ("repeatCommands");
  85   SCM current_reps = SCM_EOL;
  86   Context *where = get_outlet ()->where_defined (reps, &current_reps);
  87
  88   if (where && ly_cheap_is_list (current_reps))
  89     {
  90       current_reps = scm_cons (what, current_reps);
  91       where->set_property (reps, current_reps);
  92     }
  93 }
  94
  95 void
  96 Volta_repeat_iterator::next_element (bool side_effect)
  97 {
  98   done_count_++;
  99
 100   Sequential_iterator::next_element (side_effect);
 101
 102   if (side_effect)
 103     {
 104       if (alt_count_)
 105         {
 106           string repstr = ::to_string (rep_count_ - alt_count_ + done_count_) + ".";
 107           if (done_count_ <= 1)
 108             {
 109               alt_restores_ = SCM_EOL;
 110               if (to_boolean (get_outlet ()->get_property ("timing")))
 111                 {
 112                   for (SCM lst = get_outlet ()->get_property ("alternativeRestores");
 113                        scm_is_pair (lst);
 114                        lst = scm_cdr (lst))
 115                     {
 116                       SCM res = SCM_EOL;
 117                       Context *t = get_outlet ()->where_defined (scm_car (lst),
 118                                                                  &res);
 119                       if (t)
 120                         {
 121                           alt_restores_ = scm_cons
 122                             (scm_list_3 (t->self_scm (), scm_car (lst), res),
 123                              alt_restores_);
 124                         }
 125                     }
 126                 }
 127             }
 128           else
 129             {
 130
 131               add_repeat_command (scm_list_n (ly_symbol2scm ("volta"), SCM_BOOL_F, SCM_UNDEFINED));
 132
 133               if (done_count_ - 1 < alt_count_)
 134                 {
 135                   add_repeat_command (ly_symbol2scm ("end-repeat"));
 136
 137                   if (to_boolean (get_outlet ()->get_property ("timing")))
 138                     {
 139                       for (SCM p = alt_restores_; scm_is_pair (p); p = scm_cdr (p))
 140                         scm_apply_0 (ly_lily_module_constant ("ly:context-set-property!"),
 141                                      scm_car (p));
 142                     }
 143                 }
 144             }
 145
 146           if (done_count_ == 1 && alt_count_ < rep_count_)
 147             repstr = "1.--" + ::to_string (rep_count_ - alt_count_ + done_count_) + ".";
 148
 149           if (done_count_ <= alt_count_)
 150             add_repeat_command (scm_list_n (ly_symbol2scm ("volta"),
 151                                             ly_string2scm (repstr), SCM_UNDEFINED));
 152         }
 153       else
 154         add_repeat_command (ly_symbol2scm ("end-repeat"));
 155     }
 156 }
 157
 158 void
 159 Volta_repeat_iterator::process (Moment m)
 160 {
 161   if (first_time_)
 162     {
 163       add_repeat_command (ly_symbol2scm ("start-repeat"));
 164       first_time_ = false;
 165     }
 166   Sequential_iterator::process (m);
 167 }
 168
 169 IMPLEMENT_CTOR_CALLBACK (Volta_repeat_iterator);