]> git.donarmstrong.com Git - lilypond.git/blobdiff - lily/accidental-engraver.cc
Release: bump Welcome versions.
[lilypond.git] / lily / accidental-engraver.cc
index 19fb8b16e862ea61db39cb31defbf0899379c4e0..003b37ff318f56f11638bb099ffbfffe76efb7fc 100644 (file)
 /*
-  accidental-engraver.cc -- implement accidental_engraver
+  This file is part of LilyPond, the GNU music typesetter.
 
-  (c)  1997--2003 Han-Wen Nienhuys <hanwen@cs.uu.nl>
+  Copyright (C) 1997--2015 Han-Wen Nienhuys <hanwen@xs4all.nl>
   Modified 2001--2002 by Rune Zedeler <rz@daimi.au.dk>
-*/
 
-#include "event.hh"
+  LilyPond is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  LilyPond is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
+*/
 
+#include "accidental-placement.hh"
+#include "arpeggio.hh"
+#include "context.hh"
+#include "duration.hh"
+#include "engraver.hh"
+#include "international.hh"
 #include "item.hh"
-#include "tie.hh"
+#include "pitch.hh"
+#include "protected-scm.hh"
 #include "rhythmic-head.hh"
-#include "engraver-group-engraver.hh"
-#include "accidental-placement.hh"
+#include "separation-item.hh"
 #include "side-position-interface.hh"
-#include "engraver.hh"
-#include "arpeggio.hh"
+#include "spanner.hh"
+#include "stream-event.hh"
+#include "tie.hh"
 #include "warn.hh"
-#include "translator-group.hh"
-#include "protected-scm.hh"
-
-/**
-
 
-FIXME: should not compute vertical positioning of accidentals, but
-get them from the noteheads
+#include "translator.icc"
 
-The algorithm for accidentals should be documented, and made
-tweakable.
-
-*/
-
-struct Accidental_entry {
+class Accidental_entry
+{
+public:
   bool done_;
-  Music * melodic_;
-  Grob * accidental_;
-  Translator_group *origin_;
-  Grob*  head_;
-  Accidental_entry();
+  Stream_event *melodic_;
+  Grob *accidental_;
+  Context *origin_;
+  Engraver *origin_engraver_;
+  Grob *head_;
+  bool tied_;
+
+  Accidental_entry ();
 };
 
-Accidental_entry::Accidental_entry()
+Accidental_entry::Accidental_entry ()
 {
+  tied_ = false;
   done_ = false;
-  melodic_ =0;
+  melodic_ = 0;
   accidental_ = 0;
   origin_ = 0;
+  origin_engraver_ = 0;
   head_ = 0;
 }
 
-struct Accidental_engraver : Engraver {
+class Accidental_engraver : public Engraver
+{
+  void update_local_key_signature (SCM new_signature);
+  void create_accidental (Accidental_entry *entry, bool, bool);
+  Grob *make_standard_accidental (Stream_event *note, Grob *note_head, Engraver *trans, bool);
+  Grob *make_suggested_accidental (Stream_event *note, Grob *note_head, Engraver *trans);
+
 protected:
   TRANSLATOR_DECLARATIONS (Accidental_engraver);
-  virtual void process_music ();
-  virtual void acknowledge_grob (Grob_info);
-  virtual void stop_translation_timestep ();
-  virtual void initialize ();
-  virtual void process_acknowledged_grobs ();
+  void process_music ();
+
+  void acknowledge_end_tie (Grob_info);
+  void acknowledge_arpeggio (Grob_info);
+  void acknowledge_rhythmic_head (Grob_info);
+  void acknowledge_finger (Grob_info);
+  void acknowledge_note_column (Grob_info);
+
+  void stop_translation_timestep ();
+  void process_acknowledged ();
+
   virtual void finalize ();
-public:
+  virtual void derived_mark () const;
 
-  Protected_scm last_keysig_;
+public:
+  SCM last_keysig_;
 
-  /*
-    Urgh. Since the accidentals depend on lots of variables, we have to
-    store all information before we can really create the accidentals.
-  */
-  Link_array<Grob> left_objects_;
-  Link_array<Grob> right_objects_;
+  vector<Grob *> left_objects_;
+  vector<Grob *> right_objects_;
 
-  Grob * accidental_placement_;
+  Grob *accidental_placement_;
 
-  /*
-    The next 
-   */
-  Array<Accidental_entry> accidentals_;
-  Link_array<Grob> ties_;
+  vector<Accidental_entry> accidentals_;
+  vector<Spanner *> ties_;
+  vector<Grob *> note_columns_;
 };
 
+/*
+  localAlterations is changed at runtime, which means that references
+  in grobs should always store ly_deep_copy ()s of those.
+*/
 
-static void
-set_property_on_children (Translator_group * trans, const char * sym, SCM val)
+Accidental_engraver::Accidental_engraver (Context *c)
+  : Engraver (c)
 {
-  trans->set_property (sym, val);
-  for (SCM p = trans -> trans_group_list_; gh_pair_p (p); p = ly_cdr(p)) {
-    Translator_group *trg =  dynamic_cast<Translator_group*> (unsmob_translator (ly_car (p)));
-    set_property_on_children(trg,sym,ly_deep_copy(val));
-  }
+  accidental_placement_ = 0;
+  last_keysig_ = SCM_EOL;
 }
 
-Accidental_engraver::Accidental_engraver ()
+void
+Accidental_engraver::derived_mark () const
 {
-  accidental_placement_ = 0;
-  last_keysig_ = SCM_EOL;
+  scm_gc_mark (last_keysig_);
 }
 
 void
-Accidental_engraver::initialize ()
+Accidental_engraver::update_local_key_signature (SCM new_sig)
 {
-  last_keysig_ = get_property ("keySignature");
+  last_keysig_ = new_sig;
+  set_context_property_on_children (context (),
+                                    ly_symbol2scm ("localAlterations"),
+                                    new_sig);
+
+  Context *trans = context ()->get_parent_context ();
 
-  Translator_group * trans_ = daddy_trans_;
-  while (trans_)
+  /*
+    Reset parent contexts so that e.g. piano-accidentals won't remember old
+    cross-staff accidentals after key-sig-changes.
+  */
+
+  SCM val;
+  while (trans && trans->here_defined (ly_symbol2scm ("localAlterations"), &val))
     {
-      trans_ -> set_property ("localKeySignature",  ly_deep_copy (last_keysig_));
-      trans_ = trans_->daddy_trans_;
+      trans->set_property ("localAlterations", ly_deep_copy (last_keysig_));
+      trans = trans->get_parent_context ();
     }
-  set_property_on_children (daddy_trans_,"localKeySignature", last_keysig_);
 }
 
-/*
+struct Accidental_result
+{
+  bool need_acc;
+  bool need_restore;
 
-calculates the number of accidentals on basis of the current local key sig
-  (passed as argument)
-  Returns number of accidentals (0, 1 or 2).
-    Negative (-1 or -2) if accidental has changed.
+  Accidental_result ()
+  {
+    need_restore = need_acc = false;
+  }
 
-*/
-static int
-number_accidentals (SCM sig, Music *, Pitch *pitch, SCM curbarnum, SCM lazyness, 
-                   bool ignore_octave_b)
+  Accidental_result (bool restore, bool acc)
+  {
+    need_restore = restore;
+    need_acc = acc;
+  }
+
+  Accidental_result (SCM scm)
+  {
+    need_restore = to_boolean (scm_car (scm));
+    need_acc = to_boolean (scm_cdr (scm));
+  }
+
+  int score () const
+  {
+    return need_acc ? 1 : 0
+           + need_restore ? 1 : 0;
+  }
+};
+
+static
+Accidental_result
+check_pitch_against_rules (Pitch const &pitch, Context *origin,
+                           SCM rules, int bar_number, SCM measurepos)
 {
-  int n = pitch->get_notename ();
-  int o = pitch->get_octave();
-  int a = pitch->get_alteration ();
-  int curbarnum_i = gh_scm2int (curbarnum);
-  int accbarnum_i = 0;
-
-  SCM prev;
-  if (ignore_octave_b)
-    prev = ly_assoc_cdr (scm_int2num (n), sig);
-  else
-    prev = scm_assoc (gh_cons (scm_int2num (o), scm_int2num (n)), sig);
+  Accidental_result result;
+  SCM pitch_scm = pitch.smobbed_copy ();
+  SCM barnum_scm = scm_from_int (bar_number);
 
-  /* should really be true unless prev == SCM_BOOL_F */
-  if (gh_pair_p (prev) && gh_pair_p (ly_cdr (prev)))
-    {
-      accbarnum_i = gh_scm2int (ly_cddr (prev));
-      prev = gh_cons (ly_car (prev), ly_cadr (prev));
-    }
-  
-  /* If an accidental was not found or the accidental was too old */
-  if (prev == SCM_BOOL_F ||
-      (gh_number_p (lazyness) && curbarnum_i > accbarnum_i + gh_scm2int (lazyness)))
-    prev = scm_assoc (scm_int2num (n), sig);
+  if (scm_is_pair (rules) && !scm_is_symbol (scm_car (rules)))
+    warning (_f ("accidental typesetting list must begin with context-name: %s",
+                 ly_scm2string (scm_car (rules)).c_str ()));
 
+  for (; scm_is_pair (rules) && origin; rules = scm_cdr (rules))
+    {
+      SCM rule = scm_car (rules);
+      if (ly_is_procedure (rule))
+        {
+          SCM rule_result_scm = scm_call_4 (rule, origin->self_scm (),
+                                            pitch_scm, barnum_scm, measurepos);
+          Accidental_result rule_result (rule_result_scm);
 
-  SCM prev_acc = (prev == SCM_BOOL_F) ? scm_int2num (0) : ly_cdr (prev);
+          result.need_acc |= rule_result.need_acc;
+          result.need_restore |= rule_result.need_restore;
+        }
 
-  int p = gh_number_p (prev_acc) ? gh_scm2int (prev_acc) : 0;
+      /*
+        If symbol then it is a context name.  Scan parent contexts to
+        find it.
+      */
+      else if (scm_is_symbol (rule))
+        {
+          Context *dad = find_context_above (origin, rule);
+          if (dad)
+            origin = dad;
+        }
+      else
+        warning (_f ("procedure or context-name expected for accidental rule, found %s",
+                     print_scm_val (rule).c_str ()));
+    }
 
-  int num;
-  if (a == p && gh_number_p (prev_acc))
-    num = 0;
-  else if ( (abs (a)<abs (p) || p*a<0) && a != 0 )
-    num = 2;
-  else
-    num = 1;
-  
-  return a == p ? num : -num;
+  return result;
 }
 
-static int
-number_accidentals (Music * note, Pitch *pitch, Translator_group * origin, 
-                   SCM accidentals, SCM curbarnum)
+void
+Accidental_engraver::process_acknowledged ()
 {
-  int number = 0;
-
-  bool diff = false;
-  if (gh_pair_p (accidentals) && !gh_symbol_p (ly_car (accidentals)))
-    warning (_f ("Accidental typesetting list must begin with context-name: %s", 
-                ly_scm2string (ly_car (accidentals)).to_str0 ()));
-  
-  while (gh_pair_p (accidentals) && origin)
+  if (accidentals_.size () && !accidentals_.back ().done_)
     {
-      // If pair then it is a new accidentals typesetting rule to be checked
-      if (gh_pair_p (ly_car (accidentals)))
-       {
-         SCM type = gh_caar (accidentals);
-         SCM lazyness = gh_cdar (accidentals);
-         SCM localsig = origin->get_property ("localKeySignature");
-         
-         bool same_octave_b = 
-           gh_eq_p (ly_symbol2scm ("same-octave"), type);
-         bool any_octave_b = 
-           gh_eq_p (ly_symbol2scm ("any-octave"), type);
-
-         if (same_octave_b || any_octave_b)
-           {
-             int n = number_accidentals
-               (localsig, note, pitch, curbarnum, lazyness, any_octave_b);
-             diff = diff || (n < 0);
-             number = max (number, abs (n));     
-           }
-         else
-           warning (_f ("unknown accidental typesetting: %s. Ignored", 
-                        ly_symbol2string (type).to_str0 ()));
-       }
-      
-
-      /*
-       if symbol then it is a context name. Scan parent contexts to find it.
-      */
-      else if (gh_symbol_p (ly_car (accidentals)))
-       {
-         SCM context =ly_car (accidentals);
-         while (origin && !origin->is_alias (context))
-           origin = origin->daddy_trans_;
-      
-         if (!origin)
-           warning (_f ("Symbol is not a parent context: %s. Ignored", 
-                        ly_symbol2string (context).to_str0 ()));
-       }
-      else warning (_f ("Accidental typesetting must be pair or context-name: %s", 
-                       ly_scm2string (ly_car (accidentals)).to_str0 ()));
-      
-      accidentals = ly_cdr (accidentals);
+      SCM accidental_rules = get_property ("autoAccidentals");
+      SCM cautionary_rules = get_property ("autoCautionaries");
+      SCM measure_position = get_property ("measurePosition");
+      int barnum = measure_number (context ());
+
+      for (vsize i = 0; i < accidentals_.size (); i++)
+        {
+          if (accidentals_[i].done_)
+            continue;
+          accidentals_[i].done_ = true;
+
+          Stream_event *note = accidentals_[i].melodic_;
+          Context *origin = accidentals_[i].origin_;
+
+          Pitch *pitch = unsmob<Pitch> (note->get_property ("pitch"));
+          if (!pitch)
+            continue;
+
+          Accidental_result acc = check_pitch_against_rules (*pitch, origin, accidental_rules,
+                                                             barnum, measure_position);
+          Accidental_result caut = check_pitch_against_rules (*pitch, origin, cautionary_rules,
+                                                              barnum, measure_position);
+
+          bool cautionary = to_boolean (note->get_property ("cautionary"));
+          if (caut.score () > acc.score ())
+            {
+              acc.need_acc |= caut.need_acc;
+              acc.need_restore |= caut.need_restore;
+
+              cautionary = true;
+            }
+
+          bool forced = to_boolean (note->get_property ("force-accidental"));
+          if (!acc.need_acc && forced)
+            acc.need_acc = true;
+
+          /*
+            Cannot look for ties: it's not guaranteed that they reach
+            us before the notes.
+          */
+          if (!note->in_event_class ("trill-span-event"))
+            {
+              if (acc.need_acc)
+                create_accidental (&accidentals_[i], acc.need_restore, cautionary);
+
+              if (forced || cautionary)
+                accidentals_[i].accidental_->set_property ("forced", SCM_BOOL_T);
+            }
+        }
     }
-  return diff ? -number : number;
 }
 
 void
-Accidental_engraver::process_acknowledged_grobs ()
+Accidental_engraver::create_accidental (Accidental_entry *entry,
+                                        bool restore_natural,
+                                        bool cautionary)
 {
-  if (accidentals_.size () && !accidentals_.top().done_)
+  Stream_event *note = entry->melodic_;
+  Grob *support = entry->head_;
+  bool as_suggestion = to_boolean (entry->origin_->get_property ("suggestAccidentals"));
+  Grob *a = 0;
+  if (as_suggestion)
+    a = make_suggested_accidental (note, support, entry->origin_engraver_);
+  else
+    a = make_standard_accidental (note, support, entry->origin_engraver_, cautionary);
+
+  if (restore_natural)
     {
-      //SCM localsig = get_property ("localKeySignature");
-      SCM accidentals =  get_property ("autoAccidentals");
-      SCM cautionaries =  get_property ("autoCautionaries");
-      SCM barnum = get_property ("currentBarNumber");
-      SCM smp = get_property("measurePosition");
-      Moment mp = (unsmob_moment (smp)) ? *unsmob_moment (smp) : Moment (0);
-      if(mp.main_part_<Rational(0) && gh_number_p(barnum)) barnum = scm_int2num(gh_scm2int(barnum)-1);
-      bool extra_natural_b = get_property ("extraNatural") == SCM_BOOL_T;
-      for (int i = 0; i  < accidentals_.size (); i++) 
-       {
-         if (accidentals_[i].done_ )
-           continue;
-         accidentals_[i].done_  = true;
-         Grob * support = accidentals_[i].head_;
-         Music * note = accidentals_[i].melodic_;
-         Translator_group * origin = accidentals_[i].origin_;
-
-         Pitch * pitch = unsmob_pitch (note->get_mus_property ("pitch"));
-         int num = number_accidentals (note, pitch, origin, accidentals, barnum);
-         int num_caut = number_accidentals (note, pitch, origin, cautionaries, barnum);
-         bool cautionary = to_boolean (note->get_mus_property ("cautionary"));
-         
-         if (abs (num_caut) > abs (num))
-           {
-             num = num_caut;
-             cautionary = true;
-           }
-
-         if(num==0 && to_boolean (note->get_mus_property ("force-accidental")))
-            num=1;
-         
-         bool different = num < 0;
-         num = abs (num);
-
-         /* see if there's a tie that "changes" the accidental */
-         /* works because if there's a tie, the note to the left
-            is of the same pitch as the actual note */
-
-         Grob *tie_break_reminder = 0;
-         bool tie_changes = false;
-         for (int j = 0; j < ties_.size (); j++)
-           if (support == Tie::head (ties_[j], RIGHT))
-             {
-               tie_changes = different;
-
-               /* Enable accidentals for broken tie
-
-               We only want an accidental on a broken tie, 
-               if the tie changes the accidental.
-                  
-               Maybe check property noTieBreakForceAccidental? */
-               if (different)
-                 tie_break_reminder = ties_[j];
-               break;
-             }
-
-         if (num)
-           {
-             Grob * a = new Item (get_property ("Accidental"));
-             a->set_parent (support, Y_AXIS);
-
-             if (!accidental_placement_)
-               {
-                 accidental_placement_ = new Item (get_property ("AccidentalPlacement"));
-                 announce_grob (accidental_placement_, a->self_scm());
-               }
-             
-             Accidental_placement::add_accidental (accidental_placement_, a);
-             announce_grob (a, SCM_EOL);
-
-             
-             SCM accs = gh_cons (scm_int2num (pitch->get_alteration ()), SCM_EOL);
-             if (num == 2 && extra_natural_b)
-               accs = gh_cons (scm_int2num (0), accs);
-
-             /* TODO:
-
-             add cautionary option in accidental.
-              */
-
-             if (cautionary)
-               {
-                 a->set_grob_property ("cautionary", SCM_BOOL_T);
-               }
-             
-             if (tie_break_reminder)
-               {
-                 // TODO.
-                 a->set_grob_property ("tie", tie_break_reminder->self_scm());
-               }
-             
-             
-             support->set_grob_property ("accidental-grob", a->self_scm ());
-
-             a->set_grob_property ("accidentals", accs);
-             accidentals_[i].accidental_ = a;
- /*
-       We add the accidentals to the support of the arpeggio, so it is put left of the
-       accidentals. 
-       
-      */
-             for (int i = 0;  i < left_objects_.size ();  i++)
-               Side_position_interface::add_support (left_objects_[i], a);
-             for (int i = 0;  i < right_objects_.size ();  i++)
-               Side_position_interface::add_support (a, right_objects_[i]);
-           }
-         
-
-         /*
-           We should not record the accidental if it is the first
-           note and it is tied from the previous measure.
-
-           Checking whether it is tied also works mostly, but will it
-           always do the correct thing?
-         */
-         
-
-         int n = pitch->get_notename ();
-         int o = pitch->get_octave ();
-         int a = pitch->get_alteration ();
-         SCM on_s = gh_cons (scm_int2num (o), scm_int2num (n));
-
-         /*
-           TODO: Speed this up!
-           
-           Perhaps only check translators mentioned in the auto-accidentals?
-           -rz
-
-           TODO: profile this.
-           
-           I'd be surprised if the impact of this would be
-           measurable.  Anyway, it seems localsig doesn't change
-           every time-step, but a set_property() is done every
-           time. We could save on that, probably.
-
-           --hwn.
-           
-           
-         */
-
-         while (origin)
-           {
-             SCM localsig = origin->get_property ("localKeySignature");
-             if (tie_changes)
-               {
-                 /*
-                   Remember an alteration that is different both from
-                   that of the tied note and of the key signature.
-                 */
-                 localsig = ly_assoc_front_x
-                   (localsig, on_s, gh_cons (SCM_BOOL_T, barnum));
-               }
-             else
-               {
-                 /*
-                   not really really correct if there are more than one
-                   noteheads with the same notename.
-                 */
-                 localsig = ly_assoc_front_x
-                   (localsig, on_s, gh_cons (scm_int2num (a), barnum)); 
-               }
-             origin->set_property ("localKeySignature",  localsig);
-             origin = origin->daddy_trans_;
-           }
-       }
+      if (to_boolean (get_property ("extraNatural")))
+        a->set_property ("restore-first", SCM_BOOL_T);
+    }
+
+  entry->accidental_ = a;
+}
+
+Grob *
+Accidental_engraver::make_standard_accidental (Stream_event * /* note */,
+                                               Grob *note_head,
+                                               Engraver *trans,
+                                               bool cautionary)
+{
+  /*
+    We construct the accidentals at the originating Voice
+    level, so that we get the property settings for
+    Accidental from the respective Voice.
+  */
+  Grob *a = 0;
+  if (cautionary)
+    a = trans->make_item ("AccidentalCautionary", note_head->self_scm ());
+  else
+    a = trans->make_item ("Accidental", note_head->self_scm ());
+
+  /*
+    We add the accidentals to the support of the arpeggio,
+    so it is put left of the accidentals.
+  */
+  for (vsize i = 0; i < left_objects_.size (); i++)
+    {
+      if (ly_is_equal (left_objects_[i]->get_property ("side-axis"), scm_from_int (X_AXIS)))
+        Side_position_interface::add_support (left_objects_[i], a);
     }
+
+  for (vsize i = 0; i < right_objects_.size (); i++)
+    Side_position_interface::add_support (a, right_objects_[i]);
+
+  a->set_parent (note_head, Y_AXIS);
+
+  if (!accidental_placement_)
+    accidental_placement_ = make_item ("AccidentalPlacement",
+                                       a->self_scm ());
+
+  Accidental_placement::add_accidental
+    (accidental_placement_, a,
+     scm_is_eq (get_property ("accidentalGrouping"), ly_symbol2scm ("voice")),
+     (long) trans);
+
+  note_head->set_object ("accidental-grob", a->self_scm ());
+
+  return a;
+}
+
+Grob *
+Accidental_engraver::make_suggested_accidental (Stream_event * /* note */,
+                                                Grob *note_head,
+                                                Engraver *trans)
+{
+  Grob *a = trans->make_item ("AccidentalSuggestion", note_head->self_scm ());
+
+  Side_position_interface::add_support (a, note_head);
+  if (Grob *stem = unsmob<Grob> (a->get_object ("stem")))
+    Side_position_interface::add_support (a, stem);
+
+  a->set_parent (note_head, X_AXIS);
+  return a;
 }
 
 void
 Accidental_engraver::finalize ()
 {
-
+  last_keysig_ = SCM_EOL;
 }
 
 void
 Accidental_engraver::stop_translation_timestep ()
 {
-  for (int i = 0; i < accidentals_.size(); i++)
+  for (vsize j = ties_.size (); j--;)
     {
-      Grob *a = accidentals_[i].accidental_;
-      if (a)
-       {
-         typeset_grob (a);
-       }
+      Grob *r = Tie::head (ties_[j], RIGHT);
+      Grob *l = Tie::head (ties_[j], LEFT);
+      if (l && r)
+        {
+          // Don't mark accidentals as "tied" when the pitch is not
+          // actually the same.  This is relevant for enharmonic ties.
+          Stream_event *le = unsmob<Stream_event> (l->get_property ("cause"));
+          Stream_event *re = unsmob<Stream_event> (r->get_property ("cause"));
+          if (le && re
+              && !ly_is_equal (le->get_property ("pitch"), re->get_property ("pitch")))
+            continue;
+        }
+
+      for (vsize i = accidentals_.size (); i--;)
+        if (accidentals_[i].head_ == r)
+          {
+            if (Grob *g = accidentals_[i].accidental_)
+              {
+                g->set_object ("tie", ties_[j]->self_scm ());
+                accidentals_[i].tied_ = true;
+              }
+            ties_.erase (ties_.begin () + j);
+            break;
+          }
+    }
+
+  for (vsize i = accidentals_.size (); i--;)
+    {
+      Stream_event *note = accidentals_[i].melodic_;
+      Context *origin = accidentals_[i].origin_;
+
+      int barnum = measure_number (origin);
+
+      Pitch *pitch = unsmob<Pitch> (note->get_property ("pitch"));
+      if (!pitch)
+        continue;
+
+      int n = pitch->get_notename ();
+      int o = pitch->get_octave ();
+      Rational a = pitch->get_alteration ();
+      SCM key = scm_cons (scm_from_int (o), scm_from_int (n));
+
+      Moment end_mp = measure_position (context (),
+                                        unsmob<Duration> (note->get_property ("duration")));
+      SCM position = scm_cons (scm_from_int (barnum), end_mp.smobbed_copy ());
+
+      SCM localsig = SCM_EOL;
+      while (origin
+             && origin->where_defined (ly_symbol2scm ("localAlterations"), &localsig))
+        {
+          bool change = false;
+          if (accidentals_[i].tied_
+              && !(to_boolean (accidentals_[i].accidental_->get_property ("forced"))))
+            {
+              /*
+                Remember an alteration that is different both from
+                that of the tied note and of the key signature.
+              */
+              localsig = ly_assoc_prepend_x (localsig, key, scm_cons (ly_symbol2scm ("tied"),
+                                                                      position));
+              change = true;
+            }
+          else
+            {
+              /*
+                not really correct if there is more than one
+                note head with the same notename.
+              */
+              localsig = ly_assoc_prepend_x (localsig, key,
+                                             scm_cons (ly_rational2scm (a),
+                                                       position));
+              change = true;
+            }
+
+          if (change)
+            origin->set_property ("localAlterations", localsig);
+
+          origin = origin->get_parent_context ();
+        }
     }
 
   if (accidental_placement_)
-    typeset_grob(accidental_placement_);
-  accidental_placement_ = 00;
-  
-  accidentals_.clear();
+    for (vsize i = 0; i < note_columns_.size (); i++)
+      Separation_item::add_conditional_item (note_columns_[i], accidental_placement_);
+
+  accidental_placement_ = 0;
+  accidentals_.clear ();
+  note_columns_.clear ();
   left_objects_.clear ();
   right_objects_.clear ();
-  ties_.clear ();
 }
 
 void
-Accidental_engraver::acknowledge_grob (Grob_info info)
+Accidental_engraver::acknowledge_rhythmic_head (Grob_info info)
 {
-  Music * note =  info.music_cause ();
-
+  Stream_event *note = info.event_cause ();
   if (note
-      && note->is_mus_type("note-event")
-      && Rhythmic_head::has_interface (info.grob_))
+      && (note->in_event_class ("note-event")
+          || note->in_event_class ("trill-span-event"))
+      // option to skip accidentals on string harmonics
+      && (to_boolean (get_property ("harmonicAccidentals"))
+          || !scm_is_eq (info.grob ()->get_property ("style"),
+                         ly_symbol2scm ("harmonic")))
+      // ignore accidentals in non-printing voices like NullVoice
+      && !to_boolean (info.context ()->get_property ("nullAccidentals")))
     {
-      Accidental_entry entry ;
-      entry.head_ = info.grob_;
-      entry.origin_ = info.origin_trans_->daddy_trans_;
+      Accidental_entry entry;
+      entry.head_ = info.grob ();
+      entry.origin_engraver_ = dynamic_cast<Engraver *> (info.origin_translator ());
+      entry.origin_ = entry.origin_engraver_->context ();
       entry.melodic_ = note;
 
-      accidentals_.push (entry);
-    }
-  else if (Tie::has_interface (info.grob_))
-    {
-      ties_.push (info.grob_);
-    }
-  else if (Arpeggio::has_interface (info.grob_))
-    {
-      left_objects_.push (info.grob_); 
-    }
-  else if (info.grob_->internal_has_interface (ly_symbol2scm("finger-interface")))
-    {
-      left_objects_.push (info.grob_); 
+      accidentals_.push_back (entry);
     }
 }
 
 void
-Accidental_engraver::process_music ()
+Accidental_engraver::acknowledge_end_tie (Grob_info info)
 {
-  SCM sig = get_property ("keySignature");
+  ties_.push_back (dynamic_cast<Spanner *> (info.grob ()));
+}
 
-  /* Detect key sig changes.
-     Update all parents and children
-  */
-  if (last_keysig_ != sig)
-    {
-      Translator_group * trans_ = daddy_trans_;
-      while (trans_)
-       {
-         trans_ -> set_property ("localKeySignature",  ly_deep_copy (sig));
-         trans_ = trans_->daddy_trans_;
-       }
-      set_property_on_children(daddy_trans_,"localKeySignature", sig);
-
-      last_keysig_ = sig;
-    }
+void
+Accidental_engraver::acknowledge_note_column (Grob_info info)
+{
+  note_columns_.push_back (info.grob ());
 }
 
+void
+Accidental_engraver::acknowledge_arpeggio (Grob_info info)
+{
+  left_objects_.push_back (info.grob ());
+}
 
+void
+Accidental_engraver::acknowledge_finger (Grob_info info)
+{
+  left_objects_.push_back (info.grob ());
+}
+
+void
+Accidental_engraver::process_music ()
+{
+  SCM sig = get_property ("keyAlterations");
+  if (!scm_is_eq (last_keysig_, sig))
+    update_local_key_signature (sig);
+}
 
 
+void
+Accidental_engraver::boot ()
+{
+  ADD_ACKNOWLEDGER (Accidental_engraver, arpeggio);
+  ADD_ACKNOWLEDGER (Accidental_engraver, finger);
+  ADD_ACKNOWLEDGER (Accidental_engraver, rhythmic_head);
+  ADD_END_ACKNOWLEDGER (Accidental_engraver, tie);
+  ADD_ACKNOWLEDGER (Accidental_engraver, note_column);
+}
 
-ENTER_DESCRIPTION (Accidental_engraver,
-"Make accidentals.  Catches note heads, ties and notices key-change "
-" events.  Due to interaction with ties (which don't come together "
-" with note heads), this needs to be in a context higher than Tie_engraver.",
-              "Accidental",
-/* accepts */     "",
-              "finger-interface rhythmic-head-interface tie-interface arpeggio-interface",
-              "localKeySignature extraNatural autoAccidentals autoCautionaries",
-                  "localKeySignature");
+ADD_TRANSLATOR (Accidental_engraver,
+                /* doc */
+                "Make accidentals."
+                "  Catch note heads, ties and notices key-change events."
+                "  This engraver usually lives at Staff level, but"
+                " reads the settings for Accidental at @code{Voice} level,"
+                " so you can @code{\\override} them at @code{Voice}.",
+
+                /* create */
+                "Accidental "
+                "AccidentalCautionary "
+                "AccidentalPlacement "
+                "AccidentalSuggestion ",
+
+                /* read */
+                "autoAccidentals "
+                "autoCautionaries "
+                "internalBarNumber "
+                "extraNatural "
+                "harmonicAccidentals "
+                "accidentalGrouping "
+                "keyAlterations "
+                "localAlterations ",
+
+                /* write */
+                "localAlterations "
+               );