release: 1.5.29

[lilypond.git] / lily / time-signature-engraver.cc

diff --git a/lily/time-signature-engraver.cc b/lily/time-signature-engraver.cc
index 75d803226ba608eaa17c7cbfc6e32ab371bc0b0d..f352b498f0e84ae87391181d09fb8098136945d5 100644 (file)
--- a/lily/time-signature-engraver.cc
+++ b/lily/time-signature-engraver.cc
@@ -3,60 +3,78 @@
 
   source file of the GNU LilyPond music typesetter
 
-  (c)  1997--1998 Han-Wen Nienhuys <hanwen@cs.uu.nl>
+  (c)  1997--2002 Han-Wen Nienhuys <hanwen@cs.uu.nl>
 */
 
-#include "time-signature-engraver.hh"
 #include "time-signature.hh"
 #include "command-request.hh"
-#include "timing-engraver.hh"
-#include "engraver-group.hh"
+#include "engraver.hh"
 
-Time_signature_engraver::Time_signature_engraver()
+
+#include "engraver-group-engraver.hh"
+
+
+/**
+  generate time_signatures. 
+  */
+class Time_signature_engraver : public Engraver
+{
+  Item * time_signature_p_;
+  SCM last_time_fraction_;
+
+protected:
+  virtual void stop_translation_timestep ();
+  virtual void create_grobs ();
+public:
+  TRANSLATOR_DECLARATIONS(Time_signature_engraver);
+
+};
+
+
+Time_signature_engraver::Time_signature_engraver ()
 { 
   time_signature_p_ =0;
+  last_time_fraction_ = SCM_BOOL_F;
 }
 
 void
-Time_signature_engraver::do_process_requests()
+Time_signature_engraver::create_grobs ()
 {
-  Translator * result =
-    daddy_grav_l()->get_simple_translator (Timing_engraver::static_name());
-
-  if (!result)
+  /*
+    not rigorously safe, since the value might get GC'd and
+    reallocated in the same spot */
+  SCM fr= get_property ("timeSignatureFraction");
+  if (!time_signature_p_ && last_time_fraction_ != fr)
     {
-      warning (_ ("lost in time") + ": " + _ ("can't find") 
-        + " Timing_translator");
-      return ;
+      last_time_fraction_ = fr; 
+      time_signature_p_ = new Item (get_property ("TimeSignature"));
+      time_signature_p_->set_grob_property ("fraction",fr);
+
+      if (time_signature_p_)
+       announce_grob (time_signature_p_, 0);
     }
   
-  Timing_engraver * timing_grav_l= (Timing_engraver*) result->engraver_l ();
-  
-  Time_signature_change_req *req = timing_grav_l->time_signature_req_l();
-  if (req)
-    {
-      Array<Scalar> args;
-      args.push (req->beats_i_);
-      args.push (req->one_beat_i_);
-       
-      time_signature_p_ = new Time_signature (args);
-      time_signature_p_->break_priority_i_ = 1; // ugh
-    }
-
-  if (time_signature_p_)
-    announce_element (Score_element_info (time_signature_p_, req));
 }
 
+
+
 void
-Time_signature_engraver::do_pre_move_processing()
+Time_signature_engraver::stop_translation_timestep ()
 {
   if (time_signature_p_) 
     {
-      typeset_element (time_signature_p_);
+      typeset_grob (time_signature_p_);
       time_signature_p_ =0;
     }
 }
 
 
-ADD_THIS_TRANSLATOR(Time_signature_engraver);
-IMPLEMENT_IS_TYPE_B1(Time_signature_engraver,Engraver); 
+
+ 
+
+ENTER_DESCRIPTION(Time_signature_engraver,
+/* descr */       "Create a TimeSignature whenever @code{timeSignatureFraction} changes",
+/* creats*/       "TimeSignature",
+/* acks  */       "",
+/* reads */       "",
+/* write */       "");