* THANKS: Create skeleton for 2.1.

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

diff --git a/lily/time-signature-engraver.cc b/lily/time-signature-engraver.cc
index e6181a17b18cc691fe43ca7569969f8d5bdd7819..ff335a0f974827ffc329fcba4eede009a45a81d3 100644 (file)
--- a/lily/time-signature-engraver.cc
+++ b/lily/time-signature-engraver.cc
@@ -1,72 +1,90 @@
 /*
-  time_signature-reg.cc -- implement Time_signature_engraver
+  time-signature-engraver.cc -- implement Time_signature_engraver
 
   source file of the GNU LilyPond music typesetter
 
-  (c)  1997--2000 Han-Wen Nienhuys <hanwen@cs.uu.nl>
+  (c)  1997--2003 Han-Wen Nienhuys <hanwen@cs.uu.nl>
 */
 
 #include "time-signature.hh"
-#include "command-request.hh"
-#include "engraver.hh"
-
+#include "warn.hh"
 
+#include "engraver.hh"
 #include "engraver-group-engraver.hh"
-
+#include "misc.hh"
 
 /**
   generate time_signatures. 
   */
-class Time_signature_engraver : public Engraver {
+class Time_signature_engraver : public Engraver
+{
+  Item * time_signature_;
+  SCM last_time_fraction_;
+
 protected:
-  virtual void do_pre_move_processing();
-  virtual void process_acknowledged ();
+  virtual void stop_translation_timestep ();
+  virtual void process_music ();
 public:
-  VIRTUAL_COPY_CONS(Translator);
-  Item * time_signature_p_;
-  SCM last_time_fraction_;
-  Time_signature_engraver();
+  TRANSLATOR_DECLARATIONS(Time_signature_engraver);
 };
 
 
-Time_signature_engraver::Time_signature_engraver()
+Time_signature_engraver::Time_signature_engraver ()
 { 
-  time_signature_p_ =0;
-  last_time_fraction_ = SCM_EOL;
+  time_signature_ =0;
+  last_time_fraction_ = SCM_BOOL_F;
 }
 
 void
-Time_signature_engraver::process_acknowledged()
+Time_signature_engraver::process_music ()
 {
   /*
     not rigorously safe, since the value might get GC'd and
     reallocated in the same spot */
   SCM fr= get_property ("timeSignatureFraction");
-  if (last_time_fraction_ != fr)
+  if (!time_signature_
+      && last_time_fraction_ != fr
+      && gh_pair_p (fr))
     {
+      int den = gh_scm2int (gh_cdr (fr));
+      if (den != (1 << intlog2 (den)))
+       {
+         /*
+           Todo: should make typecheck?
+
+           OTOH, Tristan Keuris writes 8/20 in his Intermezzi.
+          */
+         warning (_f("Found strange time signature %d/%d.",
+                     den,
+                     gh_scm2int (gh_car (fr))
+                     ));
+       }
+  
+      
       last_time_fraction_ = fr; 
-      time_signature_p_ = new Item (get_property ("TimeSignature"));
-      time_signature_p_->set_elt_property ("fraction",fr);
+      time_signature_ = new Item (get_property ("TimeSignature"));
+      time_signature_->set_grob_property ("fraction",fr);
 
-      if (time_signature_p_)
-       announce_element (time_signature_p_, 0);
+      if (time_signature_)
+       announce_grob(time_signature_, SCM_EOL);
     }
-  
 }
 
-
-
 void
-Time_signature_engraver::do_pre_move_processing()
+Time_signature_engraver::stop_translation_timestep ()
 {
-  if (time_signature_p_) 
+  if (time_signature_) 
     {
-      typeset_element (time_signature_p_);
-      time_signature_p_ =0;
+      typeset_grob (time_signature_);
+      time_signature_ =0;
     }
 }
-
-
-ADD_THIS_TRANSLATOR(Time_signature_engraver);
  
 
+ENTER_DESCRIPTION(Time_signature_engraver,
+/* descr */       "Create a TimeSignature whenever @code{timeSignatureFraction} changes",
+/* creats*/       "TimeSignature",
+/* accepts */     "",
+/* acks  */      "",
+/* reads */       "",
+/* write */       "");