lily/staff-symbol-engraver.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 1997--2010 Han-Wen Nienhuys <hanwen@xs4all.nl>
   5
   6   LilyPond is free software: you can redistribute it and/or modify
   7   it under the terms of the GNU General Public License as published by
   8   the Free Software Foundation, either version 3 of the License, or
   9   (at your option) any later version.
  10
  11   LilyPond is distributed in the hope that it will be useful,
  12   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14   GNU General Public License for more details.
  15
  16   You should have received a copy of the GNU General Public License
  17   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "engraver.hh"
  21 #include "international.hh"
  22 #include "spanner.hh"
  23 #include "stream-event.hh"
  24 #include "warn.hh"
  25
  26 #include "translator.icc"
  27
  28 class Staff_symbol_engraver : public Engraver
  29 {
  30 public:
  31   TRANSLATOR_DECLARATIONS (Staff_symbol_engraver);
  32
  33 protected:
  34   Drul_array<Stream_event *> span_events_;
  35   Spanner *span_;
  36   Spanner *finished_span_;
  37   bool first_start_;
  38
  39 protected:
  40   virtual void start_spanner ();
  41   virtual void stop_spanner ();
  42
  43   void stop_translation_timestep ();
  44   virtual ~Staff_symbol_engraver ();
  45   DECLARE_ACKNOWLEDGER (grob);
  46   DECLARE_TRANSLATOR_LISTENER (staff_span);
  47   virtual void finalize ();
  48   void process_music ();
  49 };
  50
  51 Staff_symbol_engraver::~Staff_symbol_engraver ()
  52 {
  53   assert (!span_);
  54 }
  55
  56 Staff_symbol_engraver::Staff_symbol_engraver ()
  57 {
  58   finished_span_ = 0;
  59   first_start_ = true;
  60   span_ = 0;
  61   span_events_.set (0, 0);
  62 }
  63
  64 IMPLEMENT_TRANSLATOR_LISTENER (Staff_symbol_engraver, staff_span);
  65 void
  66 Staff_symbol_engraver::listen_staff_span (Stream_event *ev)
  67 {
  68   Direction d = to_dir (ev->get_property ("span-direction"));
  69   if (d)
  70     ASSIGN_EVENT_ONCE (span_events_[d], ev);
  71   else
  72     programming_error ("staff-span event has no direction");
  73 }
  74
  75 void
  76 Staff_symbol_engraver::process_music ()
  77 {
  78   if (span_events_[STOP])
  79     {
  80       finished_span_ = span_;
  81       span_ = 0;
  82       if (first_start_)
  83         first_start_ = false;
  84     }
  85
  86   if (span_events_[START]
  87       || (first_start_ && !span_events_[STOP]))
  88     start_spanner ();
  89 }
  90
  91 void
  92 Staff_symbol_engraver::start_spanner ()
  93 {
  94   if (!span_)
  95     {
  96       span_ = make_spanner ("StaffSymbol", SCM_EOL);
  97       span_->set_bound (LEFT,
  98                         unsmob_grob (get_property ("currentCommandColumn")));
  99     }
 100 }
 101
 102 void
 103 Staff_symbol_engraver::stop_spanner ()
 104 {
 105   if (!finished_span_)
 106     return;
 107
 108   if (!finished_span_->get_bound (RIGHT))
 109     finished_span_->set_bound (RIGHT, unsmob_grob (get_property ("currentCommandColumn")));
 110
 111   announce_end_grob (finished_span_,
 112                      span_events_[STOP]
 113                      ? span_events_[STOP]->self_scm ()
 114                      : SCM_EOL);
 115
 116   finished_span_ = 0;
 117 }
 118
 119 void
 120 Staff_symbol_engraver::stop_translation_timestep ()
 121 {
 122   if ((span_events_[START] || first_start_)
 123       && span_)
 124     first_start_ = false;
 125
 126   span_events_.set (0, 0);
 127   stop_spanner ();
 128 }
 129
 130 void
 131 Staff_symbol_engraver::finalize ()
 132 {
 133   finished_span_ = span_;
 134   span_ = 0;
 135   stop_spanner ();
 136 }
 137
 138 /*
 139   Todo: staff-symbol-referencer iface.
 140 */
 141 void
 142 Staff_symbol_engraver::acknowledge_grob (Grob_info s)
 143 {
 144   if (span_ || finished_span_)
 145     {
 146       Spanner *my = span_ ? span_ : finished_span_;
 147       s.grob ()->set_object ("staff-symbol", my->self_scm ());
 148     }
 149 }
 150
 151 ADD_ACKNOWLEDGER (Staff_symbol_engraver, grob);
 152
 153 ADD_TRANSLATOR (Staff_symbol_engraver,
 154                 /* doc */
 155                 "Create the constellation of five (default) staff lines.",
 156
 157                 /* create */
 158                 "StaffSymbol ",
 159
 160                 /* read */
 161                 "",
 162
 163                 /* write */
 164                 ""
 165                 );