release: 1.3.94

[lilypond.git] / lily / extender-engraver.cc

diff --git a/lily/extender-engraver.cc b/lily/extender-engraver.cc
index 92018629d931a82722b7f842b4e3450b000a0c00..5c893207eedcbd211b994948454bd97d6e63dd04 100644 (file)
--- a/lily/extender-engraver.cc
+++ b/lily/extender-engraver.cc
@@ -1,96 +1,145 @@
 /*
   extender-engraver.cc -- implement Extender_engraver
 
-  (c) 1998 Jan Nieuwenhuizen <janneke@gnu.org>
+  (c) 1999 Glen Prideaux <glenprideaux@iname.com>,
+  Han-Wen Nienhuys, Jan Nieuwenhuizen.
+  
 */
 
-#include "proto.hh"
+#include "flower-proto.hh"
 #include "musical-request.hh"
-#include "extender-engraver.hh"
-#include "extender-spanner.hh"
-#include "text-def.hh"
-#include "score-column.hh"
-#include "text-item.hh"
+#include "lyric-extender.hh"
+#include "paper-column.hh"
+#include "item.hh"
+#include "engraver.hh"
+#include "drul-array.hh"
+#include "lyric-extender.hh"
+#include "pqueue.hh"
+
+
+/**
+  Generate an centred extender.  Should make a Extender_spanner that
+  typesets a nice centred extender of varying length depending on the
+  gap between syllables.
+
+  We remember the last Item that come across. When we get a
+  request, we create the spanner, and attach the left point to the
+  last lyrics, and the right point to any lyrics we receive by
+  then.  */
+class Extender_engraver : public Engraver
+{
+  Score_element *last_lyric_l_;
+  Score_element *current_lyric_l_;
+  Extender_req* req_l_;
+  Spanner* extender_p_;
+public:
+  Extender_engraver ();
+  VIRTUAL_COPY_CONS (Translator);
+
+protected:
+  virtual void acknowledge_element (Score_element_info);
+  virtual void do_removal_processing();
+  virtual void do_process_music();
+  virtual bool do_try_music (Music*);
+  virtual void do_pre_move_processing();
+  virtual void do_post_move_processing ();
+private:
+
+};
+
 
-IMPLEMENT_IS_TYPE_B1 (Extender_engraver,Engraver);
 ADD_THIS_TRANSLATOR (Extender_engraver);
 
 Extender_engraver::Extender_engraver ()
 {
-  extender_spanner_p_ = 0;
-  span_reqs_drul_[RIGHT] = span_reqs_drul_[LEFT] = 0;
+  current_lyric_l_ = 0;
+  last_lyric_l_ = 0;
+  extender_p_ = 0;
+  req_l_ = 0;
 }
 
 void
 Extender_engraver::acknowledge_element (Score_element_info i)
 {
-  Text_item* t = (dynamic_cast<Text_item*> (i.elem_l_));
-  if (!t)
-    return;
-  if (!extender_spanner_p_)
-    return;
-  if (!span_reqs_drul_[LEFT])
-    return;
-
-  if (!extender_spanner_p_->textitem_l_drul_[LEFT])
-    extender_spanner_p_->set_textitem (LEFT, t);
-  else
-    if (span_reqs_drul_[RIGHT] && !extender_spanner_p_->textitem_l_drul_[RIGHT]) 
-      extender_spanner_p_->set_textitem (RIGHT, t);
+  // -> text_item
+  if (i.elem_l_->has_interface (ly_symbol2scm("text-item-interface")))
+
+    {
+      current_lyric_l_ = i.elem_l_;
+      if (extender_p_
+         && !extender_p_->get_bound (RIGHT)
+           )
+         {
+           Lyric_extender(extender_p_).set_textitem (RIGHT, dynamic_cast<Item*> (i.elem_l_));
+         }
+    }
 }
 
+
 bool
-Extender_engraver::do_try_request (Request* req_l)
+Extender_engraver::do_try_music (Music* r)
 {
-  Extender_req* p = dynamic_cast <Extender_req *> (req_l);
-  if (!p)
-    return false;
-
-  if (bool (extender_spanner_p_) == bool (p->spantype == Span_req::START))
-    return false;
-
-  Direction d = (!extender_spanner_p_) ? LEFT : RIGHT;
-  if (span_reqs_drul_[d] && !span_reqs_drul_[d]->equal_b (req_l))
-    return false;
+  if (Extender_req* p = dynamic_cast <Extender_req *> (r))
+    {
+      if (req_l_)
+       return false;
 
-  span_reqs_drul_[d] = p;
-  span_mom_drul_[d] = get_staff_info ().musical_l ()->when ();
-  return true;
+      req_l_ = p;
+      return true;
+    }
+  return false;
 }
 
 void
 Extender_engraver::do_removal_processing ()
 {
-  if (extender_spanner_p_)
+  if (extender_p_)
     {
-      span_reqs_drul_[LEFT]->warning (_ ("unterminated extender"));
-      extender_spanner_p_->unlink ();
-      delete extender_spanner_p_;
-      extender_spanner_p_ = 0;
-      span_reqs_drul_[RIGHT] = span_reqs_drul_[LEFT] = 0;
+      req_l_->origin ()->warning (_ ("unterminated extender"));
+      extender_p_->set_bound(RIGHT, unsmob_element (get_property ("currentCommandColumn")));
     }
 }
 
 void
-Extender_engraver::do_process_requests ()
+Extender_engraver::do_process_music ()
 {
-  if (extender_spanner_p_ || !span_reqs_drul_[LEFT])
-    return;
+  if (req_l_)
+    {
+      if (!last_lyric_l_)
+       {
+         req_l_->origin ()->warning (_ ("Nothing to connect extender to on the left.  Ignoring extender request."));
+         return;
+       }
+      
+      extender_p_ = new Spanner (get_property ("LyricExtender"));
 
-  extender_spanner_p_ = new Extender_spanner;
 
-  announce_element (Score_element_info (extender_spanner_p_, span_reqs_drul_[LEFT]));
+      Lyric_extender (extender_p_).set_textitem  (LEFT, last_lyric_l_);
+      announce_element (extender_p_, req_l_);
+    }
 }
 
+
 void
 Extender_engraver::do_pre_move_processing ()
 {
-  if (!extender_spanner_p_ || !span_reqs_drul_[RIGHT]) 
-    return;
+  if (extender_p_)
+    {
+      typeset_element (extender_p_);
+      extender_p_ = 0;
+    }
 
-  typeset_element (extender_spanner_p_);
-  
-  extender_spanner_p_ = 0;
-  span_reqs_drul_[RIGHT] = span_reqs_drul_[LEFT] = 0;
+  if (current_lyric_l_)
+    {
+      last_lyric_l_ = current_lyric_l_;
+      current_lyric_l_ =0;
+    }
+}
+
+void
+Extender_engraver::do_post_move_processing ()
+{
+  req_l_ = 0;
 }
 
+