From: Dan Eble <nine.fierce.ballads@gmail.com>
Date: Thu, 28 May 2015 01:23:45 +0000 (-0400)
Subject: Issue 4423: eliminate part combiner's array of context handles (4/4)
X-Git-Tag: release/2.19.22-1~68^2
X-Git-Url: https://git.donarmstrong.com/?a=commitdiff_plain;h=615571eda2393eba537c3ad0eb2d424f8dd218b0;p=lilypond.git

Issue 4423: eliminate part combiner's array of context handles (4/4)

The Part_combine_iterator no longer creates or keeps alive the Voice
contexts that it uses.  make-directed-part-combine-music does it.

When the Part_combine_iterator needs to redirect a child iterator, it
finds the new Voice by name among the siblings of the current Voice.
---

diff --git a/lily/part-combine-iterator.cc b/lily/part-combine-iterator.cc
index a3b54fc386..61bb19ed16 100644
--- a/lily/part-combine-iterator.cc
+++ b/lily/part-combine-iterator.cc
@@ -25,15 +25,11 @@
 #include "music-sequence.hh"
 #include "warn.hh"
 
-enum Outlet_type
-{
-  CONTEXT_ONE, CONTEXT_TWO,
-  CONTEXT_SHARED, CONTEXT_SOLO,
-  CONTEXT_NULL, NUM_OUTLETS
-};
-
-static const char *outlet_names_[NUM_OUTLETS]
-  = {"one", "two", "shared", "solo", "null"};
+static const char *const CONTEXT_ONE = "one";
+static const char *const CONTEXT_TWO = "two";
+static const char *const CONTEXT_SHARED = "shared";
+static const char *const CONTEXT_SOLO = "solo";
+static const char *const CONTEXT_NULL = "null";
 
 class Part_combine_iterator : public Music_iterator
 {
@@ -76,13 +72,8 @@ private:
   // e.g. 1 for Solo I, 2 for Solo II.
   int chosen_part_;
 
-  /*
-    TODO: this is getting off hand...
-  */
-  Context_handle handles_[NUM_OUTLETS];
-
-  void substitute_both (Outlet_type to1,
-                        Outlet_type to2);
+  void substitute_one (Music_iterator *iter, const char *voice_id);
+  void substitute_both (const char *part1_voice_id, const char *part2_voice_id);
   bool is_active_outlet (const Context *c) const;
   void kill_mmrest (Context *c);
   void chords_together ();
@@ -157,17 +148,42 @@ Part_combine_iterator::ok () const
 }
 
 void
-Part_combine_iterator::substitute_both (Outlet_type to1,
-                                        Outlet_type to2)
+Part_combine_iterator::substitute_one (Music_iterator *iter,
+                                       const char *voice_id)
+{
+  Context *c = iter->get_outlet ();
+  if (!c)
+    {
+      programming_error ("no context");
+      return;
+    }
+  c = c->get_parent_context ();
+  if (!c)
+    {
+      programming_error ("no parent context");
+      return;
+    }
+  c = find_context_below (c, ly_symbol2scm("Voice"), voice_id);
+  if (!c)
+    {
+      string s = "can not find Voice context: ";
+      s += voice_id;
+      programming_error (s);
+      return;
+    }
+  iter->substitute_outlet (iter->get_outlet (), c);
+}
+
+void
+Part_combine_iterator::substitute_both (const char *part1_voice_id,
+                                        const char *part2_voice_id)
 {
   // TODO: There is no good reason to tie the parts together here.
   // Factor out per-part stuff into a new class of iterator which
   // reads a part-specific list similar to the existing combined
   // "split-list".
-  iterators_[0]->substitute_outlet (iterators_[0]->get_outlet (),
-                                    handles_[to1].get_context ());
-  iterators_[1]->substitute_outlet (iterators_[1]->get_outlet (),
-                                    handles_[to2].get_context ());
+  substitute_one(iterators_[0], part1_voice_id);
+  substitute_one(iterators_[1], part2_voice_id);
 }
 
 bool Part_combine_iterator::is_active_outlet (const Context *c) const
@@ -204,8 +220,8 @@ Part_combine_iterator::unisono (bool silent, int newpart)
     return;
   else
     {
-      Outlet_type c1 = (newpart == 2) ? CONTEXT_NULL : CONTEXT_SHARED;
-      Outlet_type c2 = (newpart == 2) ? CONTEXT_SHARED : CONTEXT_NULL;
+      const char *c1 = (newpart == 2) ? CONTEXT_NULL : CONTEXT_SHARED;
+      const char *c2 = (newpart == 2) ? CONTEXT_SHARED : CONTEXT_NULL;
       substitute_both (c1, c2);
 
       state_ = newstate;
@@ -270,16 +286,6 @@ Part_combine_iterator::construct_children ()
   start_moment_ = get_outlet ()->now_mom ();
   split_list_ = get_music ()->get_property ("split-list");
 
-  Context *c = get_outlet ();
-
-  for (int i = 0; i < NUM_OUTLETS; i++)
-    {
-      SCM type = (i == CONTEXT_NULL) ? ly_symbol2scm ("NullVoice") : ly_symbol2scm ("Voice");
-      /* find context below c: otherwise we may create new staff for each voice */
-      c = c->find_create_context (type, outlet_names_[i], SCM_EOL);
-      handles_[i].set_context (c);
-    }
-
   SCM lst = get_music ()->get_property ("elements");
   iterators_[0] = unsmob<Music_iterator> (get_iterator (unsmob<Music> (scm_car (lst))));
   iterators_[1] = unsmob<Music_iterator> (get_iterator (unsmob<Music> (scm_cadr (lst))));
diff --git a/ly/music-functions-init.ly b/ly/music-functions-init.ly
index 78b930d462..0dfb92a1c0 100644
--- a/ly/music-functions-init.ly
+++ b/ly/music-functions-init.ly
@@ -1152,12 +1152,19 @@ parenthesize =
           two-context-settings
           shared-context-settings)
 
-   (let ((pc-music (make-part-combine-music
-                     parser (list part1 part2) direction chord-range)))
+   (let* ((pc-music (make-part-combine-music
+                     parser (list part1 part2) direction chord-range))
+          (L1 (ly:music-length part1))
+          (L2 (ly:music-length part2))
+          ;; keep the contexts alive for the full duration
+          (skip (make-skip-music (make-duration-of-length
+                                  (if (ly:moment<? L1 L2) L2 L1)))))
      #{ \context Staff <<
-          \context Voice = "one" \with #one-context-settings {}
-          \context Voice = "two" \with #two-context-settings {}
-          \context Voice = "shared" \with #shared-context-settings {}
+          \context Voice = "one" \with #one-context-settings { #skip }
+          \context Voice = "two" \with #two-context-settings { #skip }
+          \context Voice = "shared" \with #shared-context-settings { #skip }
+          \context Voice = "solo" { #skip }
+          \context NullVoice = "null" { #skip }
           #pc-music
           #(make-part-combine-marks
             default-part-combine-mark-state-machine
diff --git a/scm/define-music-display-methods.scm b/scm/define-music-display-methods.scm
index cca78ffec2..2d2a178857 100644
--- a/scm/define-music-display-methods.scm
+++ b/scm/define-music-display-methods.scm
@@ -1047,6 +1047,12 @@ Otherwise, return #f."
                                          (music 'ContextSpeccedMusic
                                                 context-id "shared"
                                                 context-type 'Voice)
+                                         (music 'ContextSpeccedMusic
+                                                context-id "solo"
+                                                context-type 'Voice)
+                                         (music 'ContextSpeccedMusic
+                                                context-id "null"
+                                                context-type 'NullVoice)
                                          ?pc-music))))
    (with-music-match
     (?pc-music (music 'PartCombineMusic))