lily/bar-engraver.cc

   1 /*
   2   bar-engraver.cc -- implement Bar_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c)  1997--2001 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7   Jan Nieuwenhuizen <janneke@gnu.org>
   8 */
   9
  10 #include "bar.hh"
  11 #include "score-engraver.hh"
  12 #include "musical-request.hh"
  13 #include "engraver-group-engraver.hh"
  14 #include "warn.hh"
  15 #include "item.hh"
  16 #include "engraver.hh"
  17
  18 /*
  19   generate bars. Either user ("|:"), or default (new measure)
  20
  21   */
  22 class Bar_engraver : public Engraver
  23 {
  24 public:
  25   Bar_engraver ();
  26   VIRTUAL_COPY_CONS (Translator);
  27   void request_bar (String type_str);
  28
  29 protected:
  30   virtual void finalize ();
  31   virtual void stop_translation_timestep ();
  32   virtual void create_grobs ();
  33
  34 private:
  35   void typeset_bar ();
  36   void create_bar ();
  37
  38   Item * bar_p_;
  39 };
  40
  41 Bar_engraver::Bar_engraver ()
  42 {
  43   bar_p_ =0;
  44 }
  45
  46 void
  47 Bar_engraver::create_bar ()
  48 {
  49   if (!bar_p_)
  50     {
  51       bar_p_ = new Item (get_property ("BarLine"));
  52
  53       SCM gl = get_property ("whichBar");
  54       if (scm_equal_p (gl, bar_p_->get_grob_property ("glyph")) != SCM_BOOL_T)
  55           bar_p_->set_grob_property ("glyph", gl);
  56
  57       announce_grob (bar_p_, 0);
  58     }
  59 }
  60
  61 void
  62 Bar_engraver::finalize ()
  63 {
  64   typeset_bar ();
  65 }
  66
  67 /*
  68   Bar_engraver should come *after* any engravers that
  69   modify whichBar
  70 */
  71 void
  72 Bar_engraver::create_grobs ()
  73 {
  74   if (!bar_p_ && gh_string_p (get_property ("whichBar")))
  75     {
  76       create_bar ();
  77     }
  78 }
  79
  80 void
  81 Bar_engraver::typeset_bar ()
  82 {
  83   if (bar_p_)
  84     {
  85       typeset_grob (bar_p_);
  86       bar_p_ =0;
  87     }
  88 }
  89
  90 /*
  91   lines may only be broken if there is a barline in all staves
  92 */
  93 void
  94 Bar_engraver::stop_translation_timestep ()
  95 {
  96   if (!bar_p_)
  97     {
  98       Score_engraver * e = 0;
  99       Translator * t  =  daddy_grav_l ();
 100       for (; !e && t;  t = t->daddy_trans_l_)
 101         {
 102           e = dynamic_cast<Score_engraver*> (t);
 103         }
 104
 105       if (!e)
 106         programming_error ("No score engraver!");
 107       else
 108         e->forbid_breaks ();    // guh. Use properties!
 109     }
 110   else
 111     typeset_bar ();
 112 }
 113
 114 ADD_THIS_TRANSLATOR (Bar_engraver);