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 #include "lily-imports.hh"
  24
  25 class Volta_repeat_iterator : public Sequential_iterator
  26 {
  27 public:
  28   DECLARE_SCHEME_CALLBACK (constructor, ());
  29   Volta_repeat_iterator ();
  30
  31   void add_repeat_command (SCM);
  32 protected:
  33   virtual SCM get_music_list () const;
  34   virtual void next_element (bool);
  35   virtual void construct_children ();
  36   virtual void process (Moment);
  37   virtual void derived_mark () const;
  38
  39   bool first_time_;
  40   int alt_count_;
  41   int rep_count_;
  42   int done_count_;
  43   SCM alt_restores_;
  44 };
  45
  46 Volta_repeat_iterator::Volta_repeat_iterator ()
  47 {
  48   done_count_ = alt_count_ = rep_count_ = 0;
  49   first_time_ = true;
  50   alt_restores_ = SCM_EOL;
  51 }
  52
  53 void
  54 Volta_repeat_iterator::derived_mark () const
  55 {
  56   scm_gc_mark (alt_restores_);
  57   Sequential_iterator::derived_mark ();
  58 }
  59
  60 SCM
  61 Volta_repeat_iterator::get_music_list ()const
  62 {
  63   return scm_cons (get_music ()->get_property ("element"),
  64                    Sequential_iterator::get_music_list ());
  65 }
  66
  67 void
  68 Volta_repeat_iterator::construct_children ()
  69 {
  70   Sequential_iterator::construct_children ();
  71
  72   SCM alts = get_music ()->get_property ("elements");
  73
  74   alt_count_ = int (scm_ilength (alts));
  75   rep_count_ = scm_to_int (get_music ()->get_property ("repeat-count"));
  76   done_count_ = 0;
  77 }
  78
  79 /*
  80   TODO: add source information for debugging
  81 */
  82 void
  83 Volta_repeat_iterator::add_repeat_command (SCM what)
  84 {
  85   SCM reps = ly_symbol2scm ("repeatCommands");
  86   SCM current_reps = SCM_EOL;
  87   Context *where = get_outlet ()->where_defined (reps, &current_reps);
  88
  89   if (where && ly_cheap_is_list (current_reps))
  90     {
  91       current_reps = scm_cons (what, current_reps);
  92       where->set_property (reps, current_reps);
  93     }
  94 }
  95
  96 void
  97 Volta_repeat_iterator::next_element (bool side_effect)
  98 {
  99   done_count_++;
 100
 101   Sequential_iterator::next_element (side_effect);
 102
 103   if (side_effect)
 104     {
 105       if (alt_count_)
 106         {
 107           string repstr = ::to_string (rep_count_ - alt_count_ + done_count_) + ".";
 108           if (done_count_ <= 1)
 109             {
 110               alt_restores_ = SCM_EOL;
 111               if (to_boolean (get_outlet ()->get_property ("timing")))
 112                 {
 113                   for (SCM lst = get_outlet ()->get_property ("alternativeRestores");
 114                        scm_is_pair (lst);
 115                        lst = scm_cdr (lst))
 116                     {
 117                       SCM res = SCM_EOL;
 118                       Context *t = get_outlet ()->where_defined (scm_car (lst),
 119                                                                  &res);
 120                       if (t)
 121                         {
 122                           alt_restores_ = scm_cons
 123                             (scm_list_3 (t->self_scm (), scm_car (lst), res),
 124                              alt_restores_);
 125                         }
 126                     }
 127                 }
 128             }
 129           else
 130             {
 131
 132               add_repeat_command (scm_list_2 (ly_symbol2scm ("volta"), SCM_BOOL_F));
 133
 134               if (done_count_ - 1 < alt_count_)
 135                 {
 136                   add_repeat_command (ly_symbol2scm ("end-repeat"));
 137
 138                   if (to_boolean (get_outlet ()->get_property ("timing")))
 139                     {
 140                       SCM mps = ly_symbol2scm ("measurePosition");
 141                       for (SCM p = alt_restores_; scm_is_pair (p); p = scm_cdr (p))
 142                         {
 143                           SCM ls = scm_car (p);
 144                           if (scm_is_eq (scm_cadr (ls), mps))
 145                             // Repeats may have different grace timing, so
 146                             // we need to adjust the measurePosition grace
 147                             // timing to that of the current alternative
 148                             // rather than that of the first.  The
 149                             // Timing_translator does this already but is
 150                             // too late to avoid bad side-effects
 151                             {
 152                               Moment mp (unsmob<Moment> (scm_caddr (ls))->main_part_,
 153                                          get_outlet ()->now_mom ().grace_part_);
 154                               Lily::ly_context_set_property_x (scm_car (ls),
 155                                                                mps,
 156                                                                mp.smobbed_copy ());
 157                             }
 158                           else
 159                             scm_apply_0 (Lily::ly_context_set_property_x, ls);
 160                         }
 161                     }
 162                 }
 163             }
 164
 165           if (done_count_ == 1 && alt_count_ < rep_count_)
 166             repstr = "1.--" + ::to_string (rep_count_ - alt_count_ + done_count_) + ".";
 167
 168           if (done_count_ <= alt_count_)
 169             add_repeat_command (scm_list_2 (ly_symbol2scm ("volta"),
 170                                             ly_string2scm (repstr)));
 171         }
 172       else
 173         add_repeat_command (ly_symbol2scm ("end-repeat"));
 174     }
 175 }
 176
 177 void
 178 Volta_repeat_iterator::process (Moment m)
 179 {
 180   if (first_time_)
 181     {
 182       add_repeat_command (ly_symbol2scm ("start-repeat"));
 183       first_time_ = false;
 184     }
 185   Sequential_iterator::process (m);
 186 }
 187
 188 IMPLEMENT_CTOR_CALLBACK (Volta_repeat_iterator);