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 "warn.hh"
  12
  13 class Cluster_engraver : public Engraver
  14 {
  15
  16 protected:
  17 TRANSLATOR_DECLARATIONS(Cluster_engraver);
  18   virtual void start_translation_timestep ();
  19   virtual bool try_music (Music *);
  20   virtual void process_music ();
  21   virtual void acknowledge_grob (Grob_info);
  22   virtual void stop_translation_timestep ();
  23
  24 private:
  25   Drul_array<Music*> reqs_drul_;
  26   Pitch pitch_min, pitch_max;
  27   Spanner *cluster;
  28   SCM columns_scm;
  29 };
  30
  31 void reset_min_max (Pitch *pitch_min, Pitch *pitch_max)
  32 {
  33   /*
  34    * (pitch_min > pitch_max) means that pitches are not yet
  35    * initialized
  36    */
  37   *pitch_min = Pitch (0, 0, +1);
  38   *pitch_max = Pitch (0, 0, -1);
  39 }
  40
  41 Cluster_engraver::Cluster_engraver ()
  42 {
  43   cluster = 0;
  44   columns_scm = SCM_EOL;
  45   reqs_drul_[LEFT] = reqs_drul_[RIGHT] = 0;
  46 }
  47
  48 bool
  49 Cluster_engraver::try_music (Music *m)
  50 {
  51   if (m->is_mus_type ("abort-event"))
  52     {
  53       reqs_drul_[START] = 0;
  54       reqs_drul_[STOP] = 0;
  55       if (cluster)
  56         {
  57           cluster->suicide ();
  58           cluster = 0;
  59           columns_scm = SCM_EOL;
  60         }
  61     }
  62   else if (m->is_mus_type ("cluster-event"))
  63     {
  64       Direction d = to_dir (m->get_mus_property ("span-direction"));
  65       reqs_drul_[d] = m;
  66       return true;
  67     }
  68   return false;
  69 }
  70
  71 void
  72 Cluster_engraver::process_music ()
  73 {
  74   if (reqs_drul_[STOP])
  75     {
  76       if (!cluster)
  77         {
  78           reqs_drul_[STOP]->origin ()->warning ("can't find start of cluster");
  79         }
  80       else
  81         {
  82           Grob *bound = unsmob_grob (get_property ("currentMusicalColumn"));
  83           cluster->set_bound (RIGHT, bound);
  84           cluster->set_grob_property ("segments", columns_scm);
  85           typeset_grob (cluster);
  86           cluster = 0;
  87           columns_scm = SCM_EOL;
  88         }
  89       reqs_drul_[STOP] = 0;
  90     }
  91   if (reqs_drul_[START])
  92     {
  93       if (cluster)
  94         {
  95           reqs_drul_[START]->origin ()->warning ("may not nest clusters");
  96         }
  97       else
  98         {
  99           SCM basicProperties = get_property ("Cluster");
 100           cluster = new Spanner (basicProperties);
 101           columns_scm = SCM_EOL;
 102           Grob *bound = unsmob_grob (get_property ("currentMusicalColumn"));
 103           cluster->set_bound (LEFT, bound);
 104           announce_grob (cluster, bound->self_scm ());
 105         }
 106       reqs_drul_[START] = 0;
 107     }
 108 }
 109
 110 void
 111 Cluster_engraver::start_translation_timestep ()
 112 {
 113   reset_min_max (&pitch_min, &pitch_max);
 114 }
 115
 116 void
 117 Cluster_engraver::stop_translation_timestep ()
 118 {
 119   if (cluster)
 120     {
 121       SCM column_scm = get_property ("currentMusicalColumn");
 122       if (column_scm == SCM_EOL)
 123         {
 124           programming_error("failed retrieving current column");
 125           return;
 126         }
 127
 128       if (Pitch::compare (pitch_min, pitch_max) <= 0)
 129         {
 130           int staff_position = pitch_min.steps ();
 131           SCM c0 = get_property ("centralCPosition");
 132           if (gh_number_p (c0))
 133             staff_position += gh_scm2int (c0);
 134           SCM segment = scm_list_n (column_scm,
 135                                     gh_int2scm (staff_position),
 136                                     pitch_min.smobbed_copy (),
 137                                     pitch_max.smobbed_copy (),
 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 same
 146              staff and hence should be ignored. */
 147         }
 148     }
 149 }
 150
 151 void
 152 Cluster_engraver::acknowledge_grob (Grob_info info)
 153 {
 154   Item *item = dynamic_cast <Item *>(info.grob_);
 155   if (item)
 156     {
 157       if (Note_head::has_interface (info.grob_))
 158         {
 159           Music *nr = info.music_cause ();
 160           if (nr && nr->is_mus_type ("note-event"))
 161             {
 162               Pitch pitch = *unsmob_pitch (nr->get_mus_property ("pitch"));
 163               if (Pitch::compare (pitch_min, pitch_max) > 0) // already init'd?
 164                 {
 165                   // not yet init'd; use current pitch to init min/max
 166                   pitch_min = pitch;
 167                   pitch_max = pitch;
 168                 }
 169               else if (Pitch::compare (pitch, pitch_max) > 0) // new max?
 170                 {
 171                   pitch_max = pitch;
 172                 }
 173               else if (Pitch::compare (pitch, pitch_min) < 0) // new min?
 174                 {
 175                   pitch_min = pitch;
 176                 }
 177             }
 178         }
 179     }
 180 }
 181
 182 ENTER_DESCRIPTION(Cluster_engraver,
 183 /* descr */     "engraves a cluster",
 184 /* creats*/     "Cluster",
 185 /* accepts */   "cluster-event",
 186 /* acks  */     "note-head-interface",
 187 /* reads */     "",
 188 /* write */     "");