lily/forbid-break-engraver.cc

   1 /*
   2   forbid-break-engraver.cc -- implement Forbid_line_break_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2002--_2005 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7 */
   8 #include "context.hh"
   9 #include "duration.hh"
  10 #include "engraver.hh"
  11 #include "grob.hh"
  12 #include "input.hh"
  13 #include "pitch.hh"
  14 #include "rhythmic-head.hh"
  15
  16 #include "translator.icc"
  17
  18 class Forbid_line_break_engraver : public Engraver
  19 {
  20 public:
  21   TRANSLATOR_DECLARATIONS (Forbid_line_break_engraver);
  22   void start_translation_timestep ();
  23 };
  24
  25 Forbid_line_break_engraver::Forbid_line_break_engraver ()
  26 {
  27 }
  28
  29 void
  30 Forbid_line_break_engraver::start_translation_timestep ()
  31 {
  32   /*
  33     Check for running note heads. This should probably be done elsewhere.
  34   */
  35   SCM busy = get_property ("busyGrobs");
  36
  37   Moment now = now_mom ();
  38   while (scm_is_pair (busy) && unsmob_moment (scm_caar (busy))->main_part_ == now.main_part_)
  39     busy = scm_cdr (busy);
  40
  41   while (scm_is_pair (busy))
  42     {
  43       Grob *g = unsmob_grob (scm_cdar (busy));
  44       if (g->internal_has_interface (ly_symbol2scm ("rhythmic-grob-interface")))
  45         context ()->get_score_context ()->set_property ("forbidBreak", SCM_BOOL_T);
  46       busy = scm_cdr (busy);
  47     }
  48 }
  49
  50 ADD_TRANSLATOR (Forbid_line_break_engraver,
  51                 /* doc */
  52                 "Forbid line breaks when note heads are still playing at some"
  53                 " point.",
  54
  55                 /* create */
  56                 "",
  57
  58                 /* read */
  59                 "busyGrobs ",
  60
  61                 /* write */
  62                 "forbidBreak "
  63                 );