release: 1.5.29

[lilypond.git] / lily / voice-devnull-engraver.cc

diff --git a/lily/voice-devnull-engraver.cc b/lily/voice-devnull-engraver.cc
index ed5e782706b56c44820057833212bcfccff4ec24..5fbcbe171ef9cfa4035455a3c234ca7918876cdd 100644 (file)
--- a/lily/voice-devnull-engraver.cc
+++ b/lily/voice-devnull-engraver.cc
@@ -3,7 +3,7 @@
 
   source file of the GNU LilyPond music typesetter
   
-  (c) 2000 Jan Nieuwenhuizen <janneke@gnu.org>
+  (c) 2000--2002 Jan Nieuwenhuizen <janneke@gnu.org>
 */
 
 #include "engraver.hh"
@@ -14,38 +14,107 @@
 class Voice_devnull_engraver : public Engraver
 {
 public:
-  VIRTUAL_COPY_CONS (Translator);
+  TRANSLATOR_DECLARATIONS(Voice_devnull_engraver);
   
 protected:
-  virtual void acknowledge_element (Score_element_info);
+  virtual bool try_music (Music *m);
+  virtual void acknowledge_grob (Grob_info);
 };
 
-ADD_THIS_TRANSLATOR (Voice_devnull_engraver);
 
-void
-Voice_devnull_engraver::acknowledge_element (Score_element_info i)
+
+static char const *eat_spanners[] = {
+  "beam",
+  "crescendo",
+  "decrescendo",
+  "slur",
+  0
+};
+
+bool
+Voice_devnull_engraver::try_music (Music *m)
 {
-  if (daddy_trans_l_->id_str_ == "two"
-      && (to_boolean (get_property ("unison"))
-         || to_boolean (get_property ("unisilence"))))
+  SCM s = get_property ("devNullVoice");
+#if 0
+  /* No need */
+  if (gh_equal_p (s, ly_symbol2scm ("never")))
+    return;
+#endif
+
+  if (gh_equal_p (s, ly_symbol2scm ("allways"))
+      || (s == SCM_EOL
+         && daddy_trans_l_->id_str_.left_str (3) == "two"
+         && (to_boolean (get_property ("unison"))
+             || to_boolean (get_property ("unisilence")))))
     {
-      static char const *junk[] = {
-       //      "beam-interface",
-       "slur-interface",
-       "tie-interface",
-       "text-item-interface",
-       "text-script-interface",
-       "dynamic-interface",
-       "crescendo-interface",
-       0
-      };
-      for (char const **p = junk; *p; *p++)
+      if (Span_req *s = dynamic_cast <Span_req *> (m))
        {
-         if (i.elem_l_->has_interface (ly_symbol2scm (*p)))
+         SCM t = s->get_mus_property ("span-type");
+        
+         for (char const **p = eat_spanners; *p; p++)
            {
-             i.elem_l_->suicide ();
-             return;
+             if (t == ly_str02scm (*p))
+               return true;
            }
        }
+      /* Ugh.  Should eat other requests, script etc. too. */  
+      else if (dynamic_cast<Tie_req*> (m))
+       return true;
     }
+  return false;
+}
+    
+static char const *junk_interfaces[] = {
+  "beam-interface",
+  "dynamic-interface",
+  "hairpin-interface",
+  "multi-measure-rest-interface",
+  "script-interface",
+  "slur-interface",
+  "text-interface",
+  "text-item-interface",
+  "text-script-interface",
+  "text-spanner-interface",
+  "tie-interface",
+  0
+};
+
+void
+Voice_devnull_engraver::acknowledge_grob (Grob_info i)
+{
+  SCM s = get_property ("devNullVoice");
+#if 0
+  /* No need, next if will never be true */
+  if (s == ly_symbol2scm ("never"))
+    return;
+#endif
+
+  if (s == ly_symbol2scm ("allways")
+      || (s == SCM_EOL
+         && daddy_trans_l_->id_str_.left_str (3) == "two"
+         && (to_boolean (get_property ("unison"))
+             || to_boolean (get_property ("unisilence")))))
+    for (char const **p = junk_interfaces; *p; p++)
+      if (i.grob_l_->has_interface (ly_symbol2scm (*p)))
+       {
+#if 0
+         /* Ugh: virtual mmrest::suicide () ? */
+         if (i.grob_l_->has_interface (ly_symbol2scm ("multi-measure-rest-interface")))
+           i.grob_l_->set_grob_property ("skip-timestep", SCM_BOOL_T);
+         else
+           ;
+#endif   
+         /* Ugh, we can suicide them, but they remain living */
+         i.grob_l_->suicide ();
+         return;
+       }
 }
+ 
+Voice_devnull_engraver::Voice_devnull_engraver(){}
+  
+ENTER_DESCRIPTION(Voice_devnull_engraver,
+/* descr */       "Kill off certain items and spanners if we're Voice `two' and unison or unisilence is set.",
+/* creats*/       "",
+/* acks  */       "grob-interface",
+/* reads */       "",
+/* write */       "");