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 ();
  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 ()
  32 {
  33   scm_gc_mark (grace_settings_);
  34 }
  35
  36 void
  37 Grace_engraver::start_translation_timestep ()
  38 {
  39   Moment now = now_mom ();
  40   if (last_moment_.grace_part_ && !now.grace_part_)
  41     {
  42       for (SCM s = grace_settings_; scm_is_pair (s); s = scm_cdr (s))
  43         {
  44           SCM context = scm_caar (s);
  45           SCM entry = scm_cdar (s);
  46           SCM grob = scm_cadr (entry);
  47           SCM sym = scm_caddr (entry);
  48
  49           execute_pushpop_property (unsmob_context (context),
  50                                     grob, sym, SCM_UNDEFINED);
  51         }
  52
  53       grace_settings_ = SCM_EOL;
  54     }
  55   else if (!last_moment_.grace_part_ && now.grace_part_)
  56     {
  57       SCM settings = get_property ("graceSettings");
  58
  59       grace_settings_ = SCM_EOL;
  60       for (SCM s = settings; scm_is_pair (s); s = scm_cdr (s))
  61         {
  62           SCM entry = scm_car (s);
  63           SCM context_name = scm_car (entry);
  64           SCM grob = scm_cadr (entry);
  65           SCM sym = scm_caddr (entry);
  66           SCM val = scm_cadr (scm_cddr (entry));
  67
  68           Context *c = context ();
  69           while (c
  70                  && c->context_name_symbol () != context_name)
  71             {
  72               c = c->get_parent_context ();
  73             }
  74
  75           if (c)
  76             {
  77               execute_pushpop_property (c,
  78                                         grob, sym, val);
  79               grace_settings_
  80                 = scm_cons (scm_cons (c->self_scm (), entry), grace_settings_);
  81             }
  82           else
  83             {
  84               programming_error ("Cannot find context");
  85               scm_display (context_name, scm_current_error_port ());
  86             }
  87         }
  88     }
  89
  90   last_moment_ = now;
  91 }
  92
  93 ADD_TRANSLATOR (Grace_engraver,
  94                 /* descr */ "Set font size and other properties for grace notes.",
  95                 /* creats*/ "",
  96                 /* accepts */ "",
  97                 /* acks  */ "",
  98                 /* reads */ "graceSettings",
  99                 /* write */ "");