lily/grob-pq-engraver.cc

   1 /*
   2   grob-pq-engraver.cc --  implement Grob_pq_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2001--2002  Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7 */
   8
   9 #include "translator-group.hh"
  10 #include "engraver.hh"
  11 #include "grob.hh"
  12 #include "warn.hh"
  13
  14 struct Grob_mom
  15 {
  16   Grob * grob_ ;
  17   Moment end_;
  18   Grob_mom () {}
  19   Grob_mom (Grob*gr, Moment e)
  20   {
  21     grob_ = gr;
  22     end_ = e;
  23   }
  24 };
  25
  26 int compare  (Grob_mom const &a, Grob_mom const &b)
  27 {
  28   return Moment::compare (a.end_, b.end_);
  29 }
  30
  31
  32 class Grob_pq_engraver: public Engraver
  33 {
  34 public:
  35   TRANSLATOR_DECLARATIONS(Grob_pq_engraver);
  36
  37   Array<Grob_mom> current_grobs_;
  38 protected:
  39   virtual void initialize ();
  40   virtual void acknowledge_grob (Grob_info);
  41   virtual void start_translation_timestep ();
  42   virtual void stop_translation_timestep ();
  43 };
  44
  45
  46 Grob_pq_engraver::Grob_pq_engraver()
  47 {
  48 }
  49
  50
  51 void
  52 Grob_pq_engraver::initialize ()
  53 {
  54   daddy_trans_->set_property ("busyGrobs", SCM_EOL);
  55 }
  56
  57 void
  58 Grob_pq_engraver::acknowledge_grob (Grob_info gi)
  59 {
  60   Music  * m = gi.music_cause ();
  61
  62   if (m)
  63     {
  64       Moment n = now_mom ();
  65       Moment l = m->length_mom ();
  66
  67       if (!l.to_bool ())
  68         return ;
  69
  70       if (n.grace_part_)
  71         {
  72           l.grace_part_ = l.main_part_;
  73           l.main_part_ = 0;
  74         }
  75
  76       current_grobs_.push (Grob_mom (gi.grob_, n + l));
  77     }
  78 }
  79
  80 LY_DEFINE(ly_grob_pq_less_p,
  81           "ly-grob-pq-less?", 2 , 0 ,0, (SCM a, SCM b),
  82           "Compare 2 Grob PQ entries. Internal")
  83 {
  84   if ( Moment::compare (*unsmob_moment (gh_car (a)),
  85                                       *unsmob_moment (gh_car (b))) < 0)
  86     return SCM_BOOL_T;
  87   else
  88     return SCM_BOOL_F;
  89 }
  90
  91
  92 void
  93 Grob_pq_engraver::stop_translation_timestep ()
  94 {
  95   Moment now = now_mom();
  96
  97   current_grobs_.sort (&compare);
  98   SCM current_list = SCM_EOL;
  99   for (int i = current_grobs_.size(); i--;)
 100     current_list = scm_cons (scm_cons (current_grobs_[i].end_.smobbed_copy(),
 101                                        current_grobs_[i].grob_->self_scm ()), current_list);
 102
 103   /*
 104     We generate some garbage here.
 105    */
 106   SCM busy = get_property ("busyGrobs");
 107   while (gh_pair_p (busy) && *unsmob_moment (gh_caar (busy)) == now)
 108     {
 109       busy = gh_cdr (busy);
 110     }
 111
 112   busy = scm_merge_x (current_list, busy, ly_grob_pq_less_p_proc);
 113   current_grobs_.clear ();
 114   daddy_trans_->set_property ("busyGrobs", busy);
 115 }
 116
 117 void
 118 Grob_pq_engraver::start_translation_timestep ()
 119 {
 120  Moment now = now_mom();
 121
 122   SCM start_busy = get_property ("busyGrobs");
 123   SCM busy = start_busy;
 124   while (gh_pair_p (busy) && *unsmob_moment (gh_caar (busy)) < now)
 125     {
 126       /*
 127         Todo: do something sensible. The grob-pq-engraver is not water
 128         tight, and stuff like tupletSpannerDuration confuses it.
 129        */
 130       programming_error (_f("Skipped something?\nGrob %s ended before I expected it to end.", unsmob_grob (gh_cdar (busy))->name().to_str0()));
 131
 132       busy = gh_cdr (busy);
 133     }
 134
 135   if (start_busy != busy)
 136     daddy_trans_->set_property ("busyGrobs", busy);
 137
 138 }
 139
 140
 141 ENTER_DESCRIPTION(Grob_pq_engraver,
 142 /* descr */       "Administrate when certain grobs (eg. note heads) stop playing; this
 143 engraver is a sort-of a failure, since it doesn't handle all sorts of borderline cases very well.
 144 ",
 145 /* creats*/       "",
 146 /* acks  */       "grob-interface",
 147 /* reads */       "busyGrobs",
 148 /* write */       "busyGrobs");