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