lily/ligature-bracket-engraver.cc

   1 /*
   2   ligature-bracket-engraver.cc -- implement Ligature__bracket_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2002 Juergen Reuter <reuter@ipd.uka.de>
   7
   8  */
   9 #include "engraver.hh"
  10 #include "musical-request.hh"
  11 #include "warn.hh"
  12 #include "drul-array.hh"
  13 #include "item.hh"
  14 #include "spanner.hh"
  15 #include "score-engraver.hh"
  16 #include "note-head.hh"
  17 #include "stem.hh"
  18 #include "rest.hh"
  19
  20 class Ligature_bracket_engraver : public Engraver
  21 {
  22   Drul_array<Span_req*> reqs_drul_;
  23
  24   Spanner *finished_ligature_bracket_p_;
  25   Spanner *ligature_bracket_p_;
  26   Span_req *prev_start_req_;
  27
  28   // moment where ligature started.
  29   Moment ligature_start_mom_;
  30   Grob *last_bound;
  31
  32 protected:
  33   virtual void stop_translation_timestep ();
  34   virtual void start_translation_timestep ();
  35   virtual void finalize ();
  36
  37   virtual void acknowledge_grob (Grob_info);
  38   virtual bool try_music (Music*);
  39   virtual void process_music ();
  40
  41 public:
  42   TRANSLATOR_DECLARATIONS(Ligature_bracket_engraver);
  43
  44 private:
  45   void typeset_ligature_bracket ();
  46 };
  47
  48
  49 Ligature_bracket_engraver::Ligature_bracket_engraver ()
  50 {
  51   ligature_bracket_p_ = 0;
  52   finished_ligature_bracket_p_ = 0;
  53   reqs_drul_[LEFT] = reqs_drul_[RIGHT] = 0;
  54   prev_start_req_ = 0;
  55   last_bound = 0;
  56 }
  57
  58 bool
  59 Ligature_bracket_engraver::try_music (Music *m)
  60 {
  61   if (Span_req *req_ = dynamic_cast<Span_req*> (m))
  62     {
  63       if (scm_equal_p (req_->get_mus_property ("span-type"),
  64                        ly_str02scm ("abort")) == SCM_BOOL_T)
  65         {
  66           reqs_drul_[START] = 0;
  67           reqs_drul_[STOP] = 0;
  68           if (ligature_bracket_p_)
  69             ligature_bracket_p_->suicide ();
  70           ligature_bracket_p_ = 0;
  71         }
  72       else if (scm_equal_p (req_->get_mus_property ("span-type"),
  73                             ly_str02scm ("ligature-bracket")) == SCM_BOOL_T)
  74         {
  75           Direction d = req_->get_span_dir ();
  76           reqs_drul_[d] = req_;
  77           return true;
  78         }
  79     }
  80   return false;
  81 }
  82
  83 void
  84 Ligature_bracket_engraver::process_music ()
  85 {
  86   if (reqs_drul_[STOP])
  87     {
  88       if (!ligature_bracket_p_)
  89         reqs_drul_[STOP]->origin ()->warning (_ ("can't find start of ligature"));
  90       else
  91         {
  92           if (!last_bound)
  93             {
  94               reqs_drul_[STOP]->origin ()->warning (_ ("no right bound"));
  95             }
  96           else
  97             {
  98               ligature_bracket_p_->set_bound (RIGHT, last_bound);
  99             }
 100         }
 101       prev_start_req_ = 0;
 102       finished_ligature_bracket_p_ = ligature_bracket_p_;
 103       ligature_bracket_p_ = 0;
 104     }
 105   last_bound = unsmob_grob (get_property ("currentMusicalColumn"));
 106
 107   if (ligature_bracket_p_)
 108     {
 109       // TODO: maybe forbid breaks only if not transcribing
 110       top_engraver ()->forbid_breaks ();
 111     }
 112   if (reqs_drul_[START])
 113     {
 114       if (ligature_bracket_p_)
 115         {
 116           reqs_drul_[START]->origin ()->warning (_ ("already have a ligature"));
 117           return;
 118         }
 119
 120       prev_start_req_ = reqs_drul_[START];
 121       ligature_bracket_p_ = new Spanner (get_property ("LigatureBracket"));
 122
 123       Grob *bound = unsmob_grob (get_property ("currentMusicalColumn"));
 124       if (!bound)
 125         {
 126           reqs_drul_[START]->origin ()->warning (_ ("no left bound"));
 127         }
 128       else
 129         {
 130           ligature_bracket_p_->set_bound (LEFT, bound);
 131         }
 132
 133       ligature_start_mom_ = now_mom ();
 134
 135       announce_grob(ligature_bracket_p_, reqs_drul_[START]->self_scm());
 136     }
 137 }
 138
 139 void
 140 Ligature_bracket_engraver::start_translation_timestep ()
 141 {
 142   reqs_drul_[START] = 0;
 143   reqs_drul_[STOP] = 0;
 144 }
 145
 146 void
 147 Ligature_bracket_engraver::typeset_ligature_bracket ()
 148 {
 149   if (finished_ligature_bracket_p_)
 150     {
 151       typeset_grob (finished_ligature_bracket_p_);
 152       finished_ligature_bracket_p_ = 0;
 153     }
 154 }
 155
 156 void
 157 Ligature_bracket_engraver::stop_translation_timestep ()
 158 {
 159   typeset_ligature_bracket ();
 160 }
 161
 162 void
 163 Ligature_bracket_engraver::finalize ()
 164 {
 165   typeset_ligature_bracket ();
 166   if (ligature_bracket_p_)
 167     {
 168       prev_start_req_->origin ()->warning (_ ("unterminated ligature"));
 169       ligature_bracket_p_->suicide ();
 170     }
 171 }
 172
 173 void
 174 Ligature_bracket_engraver::acknowledge_grob (Grob_info info)
 175 {
 176   if (ligature_bracket_p_)
 177     {
 178       if (Rest::has_interface (info.grob_l_))
 179         {
 180           reqs_drul_[START]->origin ()->warning (_ ("ligature may not contain rest; ignoring rest"));
 181           prev_start_req_->origin ()->warning (_ ("ligature was started here"));
 182           // TODO: maybe better should stop ligature here rather than
 183           // ignoring the rest?
 184         }
 185     }
 186 }
 187
 188 ENTER_DESCRIPTION(Ligature_bracket_engraver,
 189 /* descr */       "Handles Ligature_requests by engraving Ligature brackets.",
 190 /* creats*/       "LigatureBracket",
 191 /* acks  */       "rest-interface",
 192 /* reads */       "",
 193 /* write */       "");