lily/line-number-engraver.cc

   1 /*
   2   line-number-engraver.cc --  implement  Line_number_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2000 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7
   8  */
   9
  10 #include "engraver.hh"
  11 #include "text-item.hh"
  12 #include "side-position-interface.hh"
  13 #include "note-head.hh"
  14 #include "stem.hh"
  15
  16 /**
  17    Annotate output with line numbers. Creates text-items when it
  18    catches note heads.  */
  19 class Line_number_engraver : public Engraver
  20 {
  21   Array<Score_element_info> interesting_;
  22   Link_array<Score_element> support_;
  23   Item * text_item_p_;
  24   String last_text_;
  25 public:
  26   Line_number_engraver ();
  27   VIRTUAL_COPY_CONS (Translator);
  28 protected:
  29   virtual void do_pre_move_processing ();
  30   virtual void acknowledge_element (Score_element_info);
  31   virtual void process_acknowledged ();
  32 };
  33
  34 void
  35 Line_number_engraver::process_acknowledged ()
  36 {
  37   if (!text_item_p_ && interesting_.size ())
  38     {
  39       text_item_p_ = new Text_item;
  40       Side_position_interface si (text_item_p_);
  41       si.set_axis (Y_AXIS);
  42       text_item_p_->set_parent (interesting_[0].elem_l_, Y_AXIS);
  43
  44       si.set_direction (UP);
  45       announce_element (Score_element_info (text_item_p_, 0));
  46     }
  47 }
  48
  49 void
  50 Line_number_engraver::acknowledge_element (Score_element_info inf)
  51 {
  52   if (dynamic_cast<Note_head*> (inf.elem_l_))
  53     {
  54       interesting_.push (inf);
  55       support_.push (inf.elem_l_);
  56     }
  57   if (dynamic_cast<Stem*> (inf.elem_l_))
  58     {
  59       support_.push (inf.elem_l_);
  60     }
  61 }
  62
  63 void
  64 Line_number_engraver::do_pre_move_processing ()
  65 {
  66   if (text_item_p_)
  67     {
  68       String s;
  69       Side_position_interface si (text_item_p_);
  70       for (int i=0; i < interesting_.size (); i++)
  71         {
  72           if (i)
  73             s += ",";
  74
  75           s += interesting_[i].req_l_->line_number_str ();
  76
  77         }
  78
  79       for (int j= support_.size (); j--; )
  80         {
  81           si.add_support (support_[j]);
  82         }
  83       if (s != last_text_)
  84         {
  85           text_item_p_->set_elt_property ("text", ly_str02scm (s.ch_C()));
  86           last_text_ =s;
  87         }
  88
  89       typeset_element (text_item_p_);
  90       text_item_p_ =0;
  91     }
  92   interesting_.clear ();
  93   support_.clear ();
  94 }
  95
  96 Line_number_engraver::Line_number_engraver ()
  97 {
  98   text_item_p_ =0;
  99 }
 100
 101 ADD_THIS_TRANSLATOR(Line_number_engraver);