Merge remote branch 'origin/master' into release/unstable

[lilypond.git] / lily / timing-translator.cc

diff --git a/lily/timing-translator.cc b/lily/timing-translator.cc
index 03cbfdd3d43700c3cb30cc8ab6836519df6661d5..67832e3cc5ae60d9fc44154c5f33bfd2061e41f3 100644 (file)
--- a/lily/timing-translator.cc
+++ b/lily/timing-translator.cc
@@ -186,26 +186,44 @@ Timing_translator::start_translation_timestep ()
   else
     {
       measposp = now;
-      context ()->set_property ("measurePosition",
-                                measposp.smobbed_copy ());
     }
 
-  measposp += dt;
-
   int current_barnumber = robust_scm2int (get_property ("currentBarNumber"), 0);
   int internal_barnumber = robust_scm2int (get_property ("internalBarNumber"), 0);
 
   SCM cad = get_property ("timing");
   bool c = to_boolean (cad);
 
-  Rational len = measure_length ();
-  while (c && measposp.main_part_ >= len)
+  if (c)
     {
-      measposp.main_part_ -= len;
-      current_barnumber++;
-      internal_barnumber++;
+      Rational len = measure_length ();
+
+      measposp += dt;
+
+      while (measposp.main_part_ >= len)
+        {
+          measposp.main_part_ -= len;
+          current_barnumber++;
+          internal_barnumber++;
+        }
     }
 
+
+  // Because "timing" can be switched on and off asynchronously with
+  // graces, measurePosition might get into strange settings of
+  // grace_part_.  It does not actually make sense to have it diverge
+  // from the main timing.  Updating the grace part outside of the
+  // actual check for "timing" looks strange and will lead to changes
+  // of grace_part_ even when timing is off.  However, when timing is
+  // switched back on again, this will generally happen in an override
+  // that does _not_ in itself advance current_moment.  So the whole
+  // timing advance logic will only get triggered while "timing" is
+  // still of.  Maybe we should keep measurePosition.grace_part_
+  // constantly at zero anyway?
+
+  measposp.grace_part_ = now.grace_part_;
+
+
   context ()->set_property ("currentBarNumber", scm_from_int (current_barnumber));
   context ()->set_property ("internalBarNumber", scm_from_int (internal_barnumber));
   context ()->set_property ("measurePosition", measposp.smobbed_copy ());