lily/lyric-engraver.cc

   1 /*
   2   lyric-engraver.cc -- implement Lyric_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c)  1997--2000 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7   Jan Nieuwenhuizen <janneke@gnu.org>
   8 */
   9
  10 #include "engraver.hh"
  11 #include "musical-request.hh"
  12 #include "item.hh"
  13 #include "paper-def.hh"
  14 #include "font-metric.hh"
  15 #include "side-position-interface.hh"
  16
  17 /**
  18    Generate texts for lyric syllables.  We only do one lyric at a time.
  19    Multiple copies of this engraver should be used to do multiple voices.
  20  */
  21 class Lyric_engraver : public Engraver
  22 {
  23 protected:
  24   virtual void stop_translation_timestep();
  25   virtual bool try_music (Music *);
  26   virtual void create_grobs ();
  27   virtual void start_translation_timestep ();
  28
  29 public:
  30   Lyric_engraver ();
  31   VIRTUAL_COPY_CONS (Translator);
  32
  33 private:
  34   Lyric_req * req_l_;
  35   Item* text_p_;
  36 };
  37
  38 ADD_THIS_TRANSLATOR (Lyric_engraver);
  39
  40
  41 Lyric_engraver::Lyric_engraver()
  42 {
  43   text_p_ =0;
  44   req_l_ =0;
  45 }
  46
  47 bool
  48 Lyric_engraver::try_music (Music*r)
  49 {
  50   if (Lyric_req* l = dynamic_cast <Lyric_req *> (r))
  51     {
  52       if (req_l_)
  53         return false;
  54       req_l_ =l;
  55       return true;
  56     }
  57   return false;
  58 }
  59
  60 void
  61 Lyric_engraver::create_grobs ()
  62 {
  63   if (req_l_)
  64     {
  65       text_p_=  new Item (get_property ("LyricText"));
  66
  67       text_p_->set_grob_property ("text", req_l_->get_mus_property ("text"));
  68
  69       /*
  70         We can't reach the notehead where we're centered from here. So
  71         we kludge.
  72
  73         (UGH UGH, pulled amount of space out of thin air)
  74       */
  75
  76       text_p_->translate_axis (0.66, X_AXIS);
  77
  78       announce_grob (text_p_, req_l_);
  79       req_l_ = 0;
  80     }
  81 }
  82
  83 void
  84 Lyric_engraver::stop_translation_timestep()
  85 {
  86   if (text_p_)
  87     {
  88       typeset_grob (text_p_);
  89       text_p_ =0;
  90     }
  91 }
  92
  93 void
  94 Lyric_engraver::start_translation_timestep ()
  95 {
  96   req_l_ =0;
  97 }
  98
  99