lily/cluster-engraver.cc

   1 /*
   2   cluster-engraver.cc -- implement Cluster_engraver
   3
   4   (c) 2002 Juergen Reuter <reuter@ipd.uka.de>
   5 */
   6
   7 #include "engraver.hh"
   8 #include "item.hh"
   9 #include "spanner.hh"
  10 #include "note-head.hh"
  11 #include "protected-scm.hh"
  12 #include "warn.hh"
  13
  14 class Cluster_engraver : public Engraver
  15 {
  16
  17 protected:
  18 TRANSLATOR_DECLARATIONS(Cluster_engraver);
  19   virtual void start_translation_timestep ();
  20   virtual bool try_music (Music *);
  21   virtual void process_music ();
  22   virtual void acknowledge_grob (Grob_info);
  23   virtual void stop_translation_timestep ();
  24
  25 private:
  26   Drul_array<Music*> reqs_drul_;
  27   Pitch pitch_min_, pitch_max_;
  28   Spanner *cluster_;
  29   Protected_scm columns_scm_;
  30 };
  31
  32 void reset_min_max (Pitch *pitch_min, Pitch *pitch_max)
  33 {
  34   /*
  35    * (pitch_min > pitch_max) means that pitches are not yet
  36    * initialized
  37    */
  38   *pitch_min = Pitch (0, 0, +1);
  39   *pitch_max = Pitch (0, 0, -1);
  40 }
  41
  42 Cluster_engraver::Cluster_engraver ()
  43 {
  44   cluster_ = 0;
  45   columns_scm_ = SCM_EOL;
  46   reqs_drul_[LEFT] = reqs_drul_[RIGHT] = 0;
  47 }
  48
  49 bool
  50 Cluster_engraver::try_music (Music *m)
  51 {
  52   if (m->is_mus_type ("abort-event"))
  53     {
  54       reqs_drul_[START] = 0;
  55       reqs_drul_[STOP] = 0;
  56       if (cluster_)
  57         {
  58           cluster_->suicide ();
  59           cluster_ = 0;
  60           columns_scm_ = SCM_EOL;
  61         }
  62     }
  63   else if (m->is_mus_type ("cluster-event"))
  64     {
  65       Direction d = to_dir (m->get_mus_property ("span-direction"));
  66       reqs_drul_[d] = m;
  67       return true;
  68     }
  69   return false;
  70 }
  71
  72 void
  73 Cluster_engraver::process_music ()
  74 {
  75   if (reqs_drul_[STOP])
  76     {
  77       if (!cluster_)
  78         {
  79           reqs_drul_[STOP]->origin ()->warning ("can't find start of cluster");
  80         }
  81       else
  82         {
  83           Grob *bound = unsmob_grob (get_property ("currentMusicalColumn"));
  84           cluster_->set_bound (RIGHT, bound);
  85         }
  86     }
  87   if (reqs_drul_[START])
  88     {
  89       if (cluster_)
  90         {
  91           reqs_drul_[START]->origin ()->warning ("may not nest clusters");
  92         }
  93       else
  94         {
  95           SCM basicProperties = get_property ("Cluster");
  96           cluster_ = new Spanner (basicProperties);
  97           columns_scm_ = SCM_EOL;
  98           Grob *bound = unsmob_grob (get_property ("currentMusicalColumn"));
  99           cluster_->set_bound (LEFT, bound);
 100           announce_grob (cluster_, bound->self_scm ());
 101         }
 102       reqs_drul_[START] = 0;
 103     }
 104 }
 105
 106 void
 107 Cluster_engraver::start_translation_timestep ()
 108 {
 109   reset_min_max (&pitch_min_, &pitch_max_);
 110 }
 111
 112 void
 113 Cluster_engraver::stop_translation_timestep ()
 114 {
 115   if (cluster_)
 116     {
 117       SCM column_scm = get_property ("currentMusicalColumn");
 118       if (column_scm == SCM_EOL)
 119         {
 120           programming_error("failed retrieving current column");
 121         }
 122       else
 123         {
 124           if (Pitch::compare (pitch_min_, pitch_max_) <= 0)
 125             {
 126               Real y_bottom = 0.5 * pitch_min_.steps ();
 127               SCM c0 = get_property ("centralCPosition");
 128               if (gh_number_p (c0))
 129                 y_bottom += 0.5 * gh_scm2int (c0);
 130               else
 131                 programming_error ("Cluster_engraver: failed evaluating c0");
 132               Real y_top = y_bottom +
 133                 0.5 * (pitch_max_.steps () - pitch_min_.steps ());
 134               column_scm = Protected_scm (column_scm);
 135               SCM segment = scm_list_n (column_scm,
 136                                         gh_double2scm (y_bottom),
 137                                         gh_double2scm (y_top),
 138                                         SCM_UNDEFINED);
 139               segment = scm_list_n (segment, SCM_UNDEFINED);
 140               columns_scm_ = (columns_scm_ != SCM_EOL) ?
 141                 gh_append2 (columns_scm_, segment) : segment;
 142             }
 143           else
 144             {
 145               /* This timestep is caused by a different voice of the
 146                  same staff and hence should be ignored. */
 147             }
 148         }
 149
 150       if (reqs_drul_[STOP])
 151         {
 152           reqs_drul_[STOP] = 0;
 153           cluster_->set_grob_property ("segments", columns_scm_);
 154           typeset_grob (cluster_);
 155           cluster_ = 0;
 156           columns_scm_ = SCM_EOL;
 157         }
 158     }
 159 }
 160
 161 void
 162 Cluster_engraver::acknowledge_grob (Grob_info info)
 163 {
 164   Item *item = dynamic_cast <Item *>(info.grob_);
 165   if (item)
 166     {
 167       if (Note_head::has_interface (info.grob_))
 168         {
 169           Music *nr = info.music_cause ();
 170           if (nr && nr->is_mus_type ("note-event"))
 171             {
 172               Pitch pitch = *unsmob_pitch (nr->get_mus_property ("pitch"));
 173               if (Pitch::compare (pitch_min_, pitch_max_) > 0) // already init'd?
 174                 {
 175                   // not yet init'd; use current pitch to init min/max
 176                   pitch_min_ = pitch;
 177                   pitch_max_ = pitch;
 178                 }
 179               else if (Pitch::compare (pitch, pitch_max_) > 0) // new max?
 180                 {
 181                   pitch_max_ = pitch;
 182                 }
 183               else if (Pitch::compare (pitch, pitch_min_) < 0) // new min?
 184                 {
 185                   pitch_min_ = pitch;
 186                 }
 187             }
 188         }
 189     }
 190 }
 191
 192 ENTER_DESCRIPTION(Cluster_engraver,
 193 /* descr */     "engraves a cluster",
 194 /* creats*/     "Cluster",
 195 /* accepts */   "cluster-event",
 196 /* acks  */     "note-head-interface",
 197 /* reads */     "",
 198 /* write */     "");