lily/grace-engraver.cc

   1 /*
   2   grace-engraver.cc -- implement Grace_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2004--2005 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7 */
   8
   9 #include "engraver.hh"
  10 #include "context.hh"
  11 #include "warn.hh"
  12
  13 class Grace_engraver : public Engraver
  14 {
  15 protected:
  16   virtual void start_translation_timestep ();
  17   virtual void derived_mark () const;
  18
  19   TRANSLATOR_DECLARATIONS (Grace_engraver);
  20   Moment last_moment_;
  21   SCM grace_settings_;
  22 public:
  23 };
  24
  25 Grace_engraver::Grace_engraver ()
  26 {
  27   grace_settings_ = SCM_EOL;
  28 }
  29
  30 void
  31 Grace_engraver::derived_mark () const
  32 {
  33   scm_gc_mark (grace_settings_);
  34   Engraver::derived_mark ();
  35 }
  36
  37 void
  38 Grace_engraver::start_translation_timestep ()
  39 {
  40   Moment now = now_mom ();
  41   if (last_moment_.grace_part_ && !now.grace_part_)
  42     {
  43       for (SCM s = grace_settings_; scm_is_pair (s); s = scm_cdr (s))
  44         {
  45           SCM context = scm_caar (s);
  46           SCM entry = scm_cdar (s);
  47           SCM grob = scm_cadr (entry);
  48           SCM sym = scm_caddr (entry);
  49
  50           execute_pushpop_property (unsmob_context (context),
  51                                     grob, sym, SCM_UNDEFINED);
  52         }
  53
  54       grace_settings_ = SCM_EOL;
  55     }
  56   else if (!last_moment_.grace_part_ && now.grace_part_)
  57     {
  58       SCM settings = get_property ("graceSettings");
  59
  60       grace_settings_ = SCM_EOL;
  61       for (SCM s = settings; scm_is_pair (s); s = scm_cdr (s))
  62         {
  63           SCM entry = scm_car (s);
  64           SCM context_name = scm_car (entry);
  65           SCM grob = scm_cadr (entry);
  66           SCM sym = scm_caddr (entry);
  67           SCM val = scm_cadr (scm_cddr (entry));
  68
  69           Context *c = context ();
  70           while (c
  71                  && c->context_name_symbol () != context_name)
  72             {
  73               c = c->get_parent_context ();
  74             }
  75
  76           if (c)
  77             {
  78               execute_pushpop_property (c,
  79                                         grob, sym, val);
  80               grace_settings_
  81                 = scm_cons (scm_cons (c->self_scm (), entry), grace_settings_);
  82             }
  83           else
  84             {
  85               programming_error ("can't find context");
  86               scm_display (context_name, scm_current_error_port ());
  87             }
  88         }
  89     }
  90
  91   last_moment_ = now;
  92 }
  93
  94 ADD_TRANSLATOR (Grace_engraver,
  95                 /* descr */ "Set font size and other properties for grace notes.",
  96                 /* creats*/ "",
  97                 /* accepts */ "",
  98                 /* acks  */ "",
  99                 /* reads */ "graceSettings",
 100                 /* write */ "");