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--2007  Han-Wen Nienhuys <hanwen@xs4all.nl>
   7 */
   8
   9 #include "context.hh"
  10 #include "engraver.hh"
  11 #include "grob.hh"
  12 #include "warn.hh"
  13
  14 struct Grob_pq_entry
  15 {
  16   Grob *grob_;
  17   Moment end_;
  18 };
  19
  20 bool
  21 operator< (Grob_pq_entry const &a, Grob_pq_entry const &b)
  22 {
  23   return a.end_ < b.end_;
  24 }
  25
  26 class Grob_pq_engraver : public Engraver
  27 {
  28 public:
  29   TRANSLATOR_DECLARATIONS (Grob_pq_engraver);
  30 protected:
  31   virtual void initialize ();
  32   DECLARE_ACKNOWLEDGER (grob);
  33   void start_translation_timestep ();
  34   void stop_translation_timestep ();
  35   void process_acknowledged ();
  36
  37   vector<Grob_pq_entry> started_now_;
  38 };
  39
  40 Grob_pq_engraver::Grob_pq_engraver ()
  41 {
  42 }
  43
  44 void
  45 Grob_pq_engraver::initialize ()
  46 {
  47   context ()->set_property ("busyGrobs", SCM_EOL);
  48 }
  49
  50 LY_DEFINE (ly_grob_pq_less_p, "ly:grob-pq<?",
  51            2, 0, 0, (SCM a, SCM b),
  52            "Compare two grob priority queue entries."
  53            "  This is an internal function.")
  54 {
  55   if (Moment::compare (*unsmob_moment (scm_car (a)),
  56                        *unsmob_moment (scm_car (b))) < 0)
  57     return SCM_BOOL_T;
  58   else
  59     return SCM_BOOL_F;
  60 }
  61
  62 void
  63 Grob_pq_engraver::acknowledge_grob (Grob_info gi)
  64 {
  65   Stream_event *ev = gi.event_cause ();
  66
  67   if (ev
  68       && !gi.grob ()->internal_has_interface (ly_symbol2scm ("multi-measure-interface")))
  69     {
  70       Moment n = now_mom ();
  71       Moment l = get_event_length (ev, n);
  72
  73       if (!l.to_bool ())
  74         return;
  75
  76       Moment end = n + l;
  77
  78       Grob_pq_entry e;
  79       e.grob_ = gi.grob ();
  80       e.end_ = end;
  81
  82       started_now_.push_back (e);
  83     }
  84 }
  85
  86 void
  87 Grob_pq_engraver::process_acknowledged ()
  88 {
  89   vector_sort (started_now_, less<Grob_pq_entry> ());
  90   SCM lst = SCM_EOL;
  91   SCM *tail = &lst;
  92   for (vsize i = 0; i < started_now_.size (); i++)
  93     {
  94       *tail = scm_acons (started_now_[i].end_.smobbed_copy (),
  95                          started_now_[i].grob_->self_scm (),
  96                          SCM_EOL);
  97       tail = SCM_CDRLOC (*tail);
  98     }
  99
 100   SCM busy = get_property ("busyGrobs");
 101   busy = scm_merge_x (lst, busy, ly_grob_pq_less_p_proc);
 102   context ()->set_property ("busyGrobs", busy);
 103
 104   started_now_.clear ();
 105 }
 106
 107 void
 108 Grob_pq_engraver::stop_translation_timestep ()
 109 {
 110   Moment now = now_mom ();
 111   SCM start_busy = get_property ("busyGrobs");
 112   SCM busy = start_busy;
 113   while (scm_is_pair (busy) && *unsmob_moment (scm_caar (busy)) == now)
 114     busy = scm_cdr (busy);
 115
 116 }
 117
 118 void
 119 Grob_pq_engraver::start_translation_timestep ()
 120 {
 121   Moment now = now_mom ();
 122
 123   SCM start_busy = get_property ("busyGrobs");
 124   SCM busy = start_busy;
 125   while (scm_is_pair (busy) && *unsmob_moment (scm_caar (busy)) < now)
 126     {
 127       /*
 128         The grob-pq-engraver is not water tight, and stuff like
 129         tupletSpannerDuration confuses it.
 130       */
 131       busy = scm_cdr (busy);
 132     }
 133
 134   if (start_busy != busy)
 135     context ()->set_property ("busyGrobs", busy);
 136 }
 137
 138 #include "translator.icc"
 139 ADD_ACKNOWLEDGER (Grob_pq_engraver, grob);
 140 ADD_TRANSLATOR (Grob_pq_engraver,
 141                 /* doc */
 142                 "Administrate when certain grobs (e.g., note heads) stop"
 143                 " playing.",
 144
 145                 /* create */
 146                 "",
 147
 148                 /* read */
 149                 "busyGrobs ",
 150
 151                 /* write */
 152                 "busyGrobs "
 153                 );