lily/extender-engraver.cc

   1 /*
   2   extender-engraver.cc -- implement Extender_engraver
   3
   4   (c) 1999 Glen Prideaux <glenprideaux@iname.com>,
   5   Han-Wen Nienhuys, Jan Nieuwenhuizen.
   6
   7 */
   8
   9 #include "proto.hh"
  10 #include "musical-request.hh"
  11 #include "lyric-extender.hh"
  12 #include "paper-column.hh"
  13 #include "item.hh"
  14 #include "engraver.hh"
  15 #include "drul-array.hh"
  16 #include "lyric-extender.hh"
  17 #include "pqueue.hh"
  18
  19
  20 /**
  21   Generate an centred extender.  Should make a Extender_spanner that
  22   typesets a nice centred extender of varying length depending on the
  23   gap between syllables.
  24
  25   We remember the last Item that come across. When we get a
  26   request, we create the spanner, and attach the left point to the
  27   last lyrics, and the right point to any lyrics we receive by
  28   then.  */
  29 class Extender_engraver : public Engraver
  30 {
  31   Score_element *last_lyric_l_;
  32   Score_element *current_lyric_l_;
  33   Extender_req* req_l_;
  34   Spanner* extender_p_;
  35 public:
  36   Extender_engraver ();
  37   VIRTUAL_COPY_CONS (Translator);
  38
  39 protected:
  40   virtual void acknowledge_element (Score_element_info);
  41   virtual void do_removal_processing();
  42   virtual void do_process_music();
  43   virtual bool do_try_music (Music*);
  44   virtual void do_pre_move_processing();
  45   virtual void do_post_move_processing ();
  46 private:
  47
  48 };
  49
  50
  51 ADD_THIS_TRANSLATOR (Extender_engraver);
  52
  53 Extender_engraver::Extender_engraver ()
  54 {
  55   current_lyric_l_ = 0;
  56   last_lyric_l_ = 0;
  57   extender_p_ = 0;
  58   req_l_ = 0;
  59 }
  60
  61 void
  62 Extender_engraver::acknowledge_element (Score_element_info i)
  63 {
  64   // -> text_item
  65   if (dynamic_cast<Item*> (i.elem_l_)
  66       && to_boolean (i.elem_l_->get_elt_property ("text-item-interface")))
  67     {
  68       current_lyric_l_ = i.elem_l_;
  69       if (extender_p_
  70           && !extender_p_->get_bound (RIGHT)
  71             )
  72           {
  73             Lyric_extender(extender_p_).set_textitem (RIGHT, dynamic_cast<Item*> (i.elem_l_));
  74           }
  75     }
  76 }
  77
  78
  79 bool
  80 Extender_engraver::do_try_music (Music* r)
  81 {
  82   if (Extender_req* p = dynamic_cast <Extender_req *> (r))
  83     {
  84       if (req_l_)
  85         return false;
  86
  87       req_l_ = p;
  88       return true;
  89     }
  90   return false;
  91 }
  92
  93 void
  94 Extender_engraver::do_removal_processing ()
  95 {
  96   if (extender_p_)
  97     {
  98       req_l_->warning (_ ("unterminated extender"));
  99       extender_p_->set_bound(RIGHT, unsmob_element (get_property ("currentCommandColumn")));
 100     }
 101 }
 102
 103 void
 104 Extender_engraver::do_process_music ()
 105 {
 106   if (req_l_)
 107     {
 108       if (!last_lyric_l_)
 109         {
 110           req_l_->warning (_ ("Nothing to connect extender to on the left.  Ignoring extender request."));
 111           return;
 112         }
 113
 114       extender_p_ = new Spanner (get_property ("basicLyricExtenderProperties"));
 115       extender_p_->set_extent_callback (Score_element::point_dimension_callback, Y_AXIS);
 116
 117       Lyric_extender (extender_p_).set_textitem  (LEFT, last_lyric_l_);
 118       announce_element (Score_element_info (extender_p_, req_l_));
 119     }
 120 }
 121
 122
 123 void
 124 Extender_engraver::do_pre_move_processing ()
 125 {
 126   if (extender_p_)
 127     {
 128       typeset_element (extender_p_);
 129       extender_p_ = 0;
 130     }
 131
 132   if (current_lyric_l_)
 133     {
 134       last_lyric_l_ = current_lyric_l_;
 135       current_lyric_l_ =0;
 136     }
 137 }
 138
 139 void
 140 Extender_engraver::do_post_move_processing ()
 141 {
 142   req_l_ = 0;
 143 }
 144
 145