X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=lily%2Ftime-signature-engraver.cc;h=5ff450422fa35f1ad53e4b96c12845b94c697ce5;hb=eea589c2d7bee6ab38bc611eb205d4c74e2011f7;hp=bba35fe2b1d9421f1f3ea7cd4ab034eb03a210e7;hpb=59e4ae99bad964d00dc167919779301c5ec2a535;p=lilypond.git

diff --git a/lily/time-signature-engraver.cc b/lily/time-signature-engraver.cc
index bba35fe2b1..5ff450422f 100644
--- a/lily/time-signature-engraver.cc
+++ b/lily/time-signature-engraver.cc
@@ -1,65 +1,81 @@
 /*
-  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--1999 Han-Wen Nienhuys <hanwen@cs.uu.nl>
+  (c) 1997--2004 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 "warn.hh"
 #include "engraver-group-engraver.hh"
+#include "misc.hh"
 
-Time_signature_engraver::Time_signature_engraver()
+/**
+  generate time_signatures. 
+  */
+class Time_signature_engraver : public Engraver
+{
+  Item *time_signature_;
+  SCM last_time_fraction_;
+
+protected:
+  virtual void stop_translation_timestep ();
+  virtual void process_music ();
+public:
+  TRANSLATOR_DECLARATIONS (Time_signature_engraver);
+};
+
+
+Time_signature_engraver::Time_signature_engraver ()
 { 
-  time_signature_p_ =0;
+  time_signature_ = 0;
+  last_time_fraction_ = SCM_BOOL_F;
 }
 
 void
-Time_signature_engraver::do_process_requests()
+Time_signature_engraver::process_music ()
 {
-  Translator * result =
-    daddy_grav_l()->get_simple_translator ("Timing_engraver");	// ugh
-
-  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_
+      && last_time_fraction_ != fr
+      && scm_is_pair (fr))
     {
-      warning (_ ("lost in time:"));
-      warning (_f ("Can't find: `%s'", " Timing_translator"));
-      return ;
-    }
-  
-  Timing_engraver * timing_grav_l= dynamic_cast<Timing_engraver *> (result);
-  
-  Time_signature_change_req *req = timing_grav_l->time_signature_req_l();
-  if (req)
-    {
-      Array<int> args;
-      args.push (req->beats_i_);
-      args.push (req->one_beat_i_);
-	
-      time_signature_p_ = new Time_signature;
-      time_signature_p_->args_ = args;
-      time_signature_p_->set_elt_property ("break-aligned", SCM_BOOL_T);
-    }
+      int den = scm_to_int (scm_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,
+		      scm_to_int (scm_car (fr))
+		      ));
+	}
   
-  if (time_signature_p_)
-    announce_element (Score_element_info (time_signature_p_, req));
+      
+      last_time_fraction_ = fr; 
+      time_signature_ = make_item ("TimeSignature",SCM_EOL);
+      time_signature_->set_property ("fraction",fr);
+    }
 }
 
 void
-Time_signature_engraver::do_pre_move_processing()
+Time_signature_engraver::stop_translation_timestep ()
 {
-  if (time_signature_p_) 
-    {
-      typeset_element (time_signature_p_);
-      time_signature_p_ =0;
-    }
+  time_signature_ = 0;
 }
-
-
-ADD_THIS_TRANSLATOR(Time_signature_engraver);
  
 
+ADD_TRANSLATOR (Time_signature_engraver,
+/* descr */       "Create a TimeSignature whenever @code{timeSignatureFraction} changes",
+/* creats*/       "TimeSignature",
+/* accepts */     "",
+/* acks  */      "",
+/* reads */       "",
+/* write */       "");