lily/key-performer.cc

   1 /*
   2   key-performer.cc -- implement Key_performer
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1997 Jan Nieuwenhuizen <jan@digicash.com>
   7 */
   8
   9 #include "key-performer.hh"
  10 #include "command-request.hh"
  11 #include "audio-item.hh"
  12
  13
  14
  15 IMPLEMENT_IS_TYPE_B1(Key_performer,Performer);
  16 ADD_THIS_TRANSLATOR(Key_performer);
  17
  18 Key_performer::Key_performer()
  19 {
  20   key_req_l_ = 0;
  21 }
  22
  23 Key_performer::~Key_performer()
  24 {
  25 }
  26
  27 void
  28 Key_performer::do_print() const
  29 {
  30 #ifndef NPRINT
  31   if (key_req_l_)
  32         key_req_l_->print();
  33 #endif
  34 }
  35
  36 void
  37 Key_performer::do_process_requests()
  38 {
  39   if (key_req_l_)
  40         play (new Audio_key (key_req_l_));
  41   key_req_l_ = 0;
  42 }
  43
  44 bool
  45 Key_performer::do_try_request (Request* req_l)
  46 {
  47   if (key_req_l_)
  48         return false;
  49
  50   if (req_l->command())
  51         key_req_l_ = req_l->command()->keychange ();
  52
  53   if (key_req_l_)
  54         return true;
  55
  56   return false;
  57 }
  58