X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=lily%2Fpartial-iterator.cc;h=80048d827c87bcec64bdefc0615e041d93409533;hb=77267b700c377fd170abcbf4863728937038eb5e;hp=7c3b3e965b56f171ef2e3761c7c9a85867581ad0;hpb=32689b75bec62313992c1b452f624d65f45e8789;p=lilypond.git

diff --git a/lily/partial-iterator.cc b/lily/partial-iterator.cc
index 7c3b3e965b..80048d827c 100644
--- a/lily/partial-iterator.cc
+++ b/lily/partial-iterator.cc
@@ -1,7 +1,7 @@
 /*
   This file is part of LilyPond, the GNU music typesetter.
 
-  Copyright (C) 2010--2012 Neil Puttock <n.puttock@gmail.com>
+  Copyright (C) 2010--2015 Neil Puttock <n.puttock@gmail.com>
 
   LilyPond is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -18,16 +18,19 @@
 */
 
 #include "context.hh"
+#include "global-context.hh"
 #include "input.hh"
 #include "international.hh"
 #include "moment.hh"
 #include "music.hh"
 #include "simple-music-iterator.hh"
+#include "lily-imports.hh"
 
 class Partial_iterator : public Simple_music_iterator
 {
 public:
   DECLARE_SCHEME_CALLBACK (constructor, ());
+  DECLARE_SCHEME_CALLBACK (finalization, (SCM, SCM));
 protected:
   virtual void process (Moment);
 };
@@ -36,16 +39,43 @@ void
 Partial_iterator::process (Moment m)
 {
   if (Duration * dur
-      = unsmob_duration (get_music ()->get_property ("duration")))
+      = unsmob<Duration> (get_music ()->get_property ("duration")))
     {
-      Context *ctx = get_outlet ();
-      Moment now = ctx->now_mom ();
-      if (now.main_part_ > Rational (0))
-        get_music ()->origin ()->
-        warning (_ ("trying to use \\partial after the start of a piece"));
       Moment length = Moment (dur->get_length ());
-      now = Moment (0, now.grace_part_);
-      ctx->set_property ("measurePosition", (now - length).smobbed_copy ());
+
+      // Partial_iterator is an iterator rather than an engraver,
+      // so the active context it is getting called in does not
+      // depend on which context definition the engraver might be
+      // defined.
+      //
+      // Using where_defined to find the context where
+      // measurePosition should be overwritten does not actually
+      // work since the Timing_translator does not set
+      // measurePosition when initializing.
+
+      Context *timing = unsmob<Context>
+        (Lily::ly_context_find (get_outlet ()->self_scm (),
+                                ly_symbol2scm ("Timing")));
+
+      if (!timing)
+        programming_error ("missing Timing in \\partial");
+      else if (get_outlet ()->now_mom () > 0)
+        {
+          timing->set_property ("partialBusy", ly_bool2scm (true));
+          Global_context *tg = get_outlet ()->get_global_context ();
+          tg->add_finalization (scm_list_3 (finalization_proc,
+                                            get_outlet ()->self_scm (),
+                                            length.smobbed_copy ()));
+        }
+      else
+        {
+          Moment mp = robust_scm2moment
+                      (timing->get_property ("measurePosition"),
+                       Rational (0));
+          mp.main_part_ = 0;
+          timing->set_property
+          ("measurePosition", (mp - length).smobbed_copy ());
+        }
     }
   else
     programming_error ("invalid duration in \\partial");
@@ -54,3 +84,25 @@ Partial_iterator::process (Moment m)
 }
 
 IMPLEMENT_CTOR_CALLBACK (Partial_iterator);
+
+MAKE_SCHEME_CALLBACK (Partial_iterator, finalization, 2);
+SCM
+Partial_iterator::finalization (SCM ctx, SCM length)
+{
+  LY_ASSERT_SMOB (Context, ctx, 1);
+  LY_ASSERT_SMOB (Moment, length, 2);
+  Context *timing = unsmob<Context>
+    (Lily::ly_context_find (ctx, ly_symbol2scm ("Timing")));
+  if (!timing) {
+    programming_error ("missing Timing in \\partial");
+    return SCM_UNSPECIFIED;
+  }
+  Moment mp = robust_scm2moment (timing->get_property ("measurePosition"),
+                                 Rational (0));
+  mp.main_part_ = measure_length (timing);
+  timing->set_property ("measurePosition",
+                        (mp - *unsmob<Moment> (length)).smobbed_copy ());
+  timing->unset_property (ly_symbol2scm ("partialBusy"));
+
+  return SCM_UNSPECIFIED;
+}