lily/staff-symbol-engraver.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 1997--2011 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   if (span_)
  54     {
  55       // Somehow finalize() was not called?
  56       programming_error ("Have a pending spanner in destructor.");
  57     }
  58 }
  59
  60 Staff_symbol_engraver::Staff_symbol_engraver ()
  61 {
  62   finished_span_ = 0;
  63   first_start_ = true;
  64   span_ = 0;
  65   span_events_.set (0, 0);
  66 }
  67
  68 IMPLEMENT_TRANSLATOR_LISTENER (Staff_symbol_engraver, staff_span);
  69 void
  70 Staff_symbol_engraver::listen_staff_span (Stream_event *ev)
  71 {
  72   Direction d = to_dir (ev->get_property ("span-direction"));
  73   if (d)
  74     ASSIGN_EVENT_ONCE (span_events_[d], ev);
  75   else
  76     programming_error ("staff-span event has no direction");
  77 }
  78
  79 void
  80 Staff_symbol_engraver::process_music ()
  81 {
  82   if (span_events_[STOP])
  83     {
  84       finished_span_ = span_;
  85       span_ = 0;
  86       if (first_start_)
  87         first_start_ = false;
  88     }
  89
  90   if (span_events_[START]
  91       || (first_start_ && !span_events_[STOP]))
  92     start_spanner ();
  93 }
  94
  95 void
  96 Staff_symbol_engraver::start_spanner ()
  97 {
  98   if (!span_)
  99     {
 100       span_ = make_spanner ("StaffSymbol", SCM_EOL);
 101       span_->set_bound (LEFT,
 102                         unsmob_grob (get_property ("currentCommandColumn")));
 103     }
 104 }
 105
 106 void
 107 Staff_symbol_engraver::stop_spanner ()
 108 {
 109   if (!finished_span_)
 110     return;
 111
 112   if (!finished_span_->get_bound (RIGHT))
 113     finished_span_->set_bound (RIGHT, unsmob_grob (get_property ("currentCommandColumn")));
 114
 115   announce_end_grob (finished_span_,
 116                      span_events_[STOP]
 117                      ? span_events_[STOP]->self_scm ()
 118                      : SCM_EOL);
 119
 120   finished_span_ = 0;
 121 }
 122
 123 void
 124 Staff_symbol_engraver::stop_translation_timestep ()
 125 {
 126   if ((span_events_[START] || first_start_)
 127       && span_)
 128     first_start_ = false;
 129
 130   span_events_.set (0, 0);
 131   stop_spanner ();
 132 }
 133
 134 void
 135 Staff_symbol_engraver::finalize ()
 136 {
 137   finished_span_ = span_;
 138   span_ = 0;
 139   stop_spanner ();
 140 }
 141
 142 /*
 143   Todo: staff-symbol-referencer iface.
 144 */
 145 void
 146 Staff_symbol_engraver::acknowledge_grob (Grob_info s)
 147 {
 148   if (span_ || finished_span_)
 149     {
 150       Spanner *my = span_ ? span_ : finished_span_;
 151       s.grob ()->set_object ("staff-symbol", my->self_scm ());
 152     }
 153 }
 154
 155 ADD_ACKNOWLEDGER (Staff_symbol_engraver, grob);
 156
 157 ADD_TRANSLATOR (Staff_symbol_engraver,
 158                 /* doc */
 159                 "Create the constellation of five (default) staff lines.",
 160
 161                 /* create */
 162                 "StaffSymbol ",
 163
 164                 /* read */
 165                 "",
 166
 167                 /* write */
 168                 ""
 169                 );