lily/engraver.cc

   1 /*
   2   engraver.cc -- implement Engraver
   3
   4   Sourcefile of GNU LilyPond music type setter
   5
   6   (c) 1997--2008 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7 */
   8
   9 #include "engraver.hh"
  10
  11 #include "context.hh"
  12 #include "international.hh"
  13 #include "music.hh"
  14 #include "paper-column.hh"
  15 #include "score-engraver.hh"
  16 #include "spanner.hh"
  17 #include "stream-event.hh"
  18 #include "warn.hh"
  19
  20 Engraver_group *
  21 Engraver::get_daddy_engraver () const
  22 {
  23   return dynamic_cast<Engraver_group *> (get_daddy_translator ());
  24 }
  25
  26 void
  27 Engraver::announce_grob (Grob_info inf)
  28 {
  29   get_daddy_engraver ()->announce_grob (inf);
  30 }
  31
  32 void
  33 Engraver::announce_end_grob (Grob_info inf)
  34 {
  35   get_daddy_engraver ()->announce_grob (inf);
  36 }
  37
  38 /*
  39   CAUSE is the object (typically a Stream_event object)  that
  40   was the reason for making E.
  41 */
  42 void
  43 Engraver::announce_grob (Grob *e, SCM cause)
  44 {
  45   /* TODO: Remove Music code when it's no longer needed */
  46   if (Music *m = unsmob_music (cause))
  47     {
  48       cause = m->to_event ()->unprotect ();
  49     }
  50   if (unsmob_stream_event (cause) || unsmob_grob (cause))
  51     e->set_property ("cause", cause);
  52
  53   Grob_info i (this, e);
  54
  55   Engraver_group *g = get_daddy_engraver ();
  56   if (g)
  57     g->announce_grob (i);
  58 }
  59
  60
  61 /*
  62   CAUSE is the object (typically a Music object)  that
  63   was the reason for making E.
  64 */
  65 void
  66 Engraver::announce_end_grob (Grob *e, SCM cause)
  67 {
  68   /* TODO: Remove Music code when it's no longer needed */
  69   if (Music *m = unsmob_music (cause))
  70     {
  71       cause = m->to_event ()->unprotect ();
  72     }
  73   if (e->get_property ("cause") == SCM_EOL
  74       && (unsmob_stream_event (cause) || unsmob_grob (cause)))
  75     e->set_property ("cause", cause);
  76
  77   Grob_info i (this, e);
  78
  79   i.start_end_ = STOP;
  80   Engraver_group *g = get_daddy_engraver ();
  81   if (g)
  82     g->announce_grob (i);
  83 }
  84
  85
  86 Engraver::Engraver ()
  87 {
  88 }
  89
  90 #ifndef NDEBUG
  91 static SCM creation_callback = SCM_EOL;
  92 LY_DEFINE (ly_set_grob_creation_callback, "ly:set-grob-creation-callback",
  93            1, 0, 0, (SCM cb),
  94            "Specify a procedure that will be called every time a new grob"
  95            " is created.  The callback will receive as arguments the grob"
  96            " that was created, the name of the C++ source file that caused"
  97            " the grob to be created, and the corresponding line number in"
  98            " the C++ source file.")
  99 {
 100   LY_ASSERT_TYPE (ly_is_procedure, cb, 1);
 101
 102   creation_callback = cb;
 103
 104   return SCM_UNSPECIFIED;
 105 }
 106 #endif
 107
 108 Grob *
 109 Engraver::internal_make_grob (SCM symbol, SCM cause, char const *name, char const *file, int line, char const *fun)
 110 {
 111   (void) file;
 112   (void) fun;
 113   (void) line;
 114   (void) name;
 115
 116   SCM props = updated_grob_properties (context (), symbol);
 117
 118   Grob *grob = 0;
 119
 120   SCM handle = scm_sloppy_assq (ly_symbol2scm ("meta"), props);
 121   SCM klass = scm_cdr (scm_sloppy_assq (ly_symbol2scm ("class"), scm_cdr (handle)));
 122
 123   if (klass == ly_symbol2scm ("Item"))
 124     grob = new Item (props);
 125   else if (klass == ly_symbol2scm ("Spanner"))
 126     grob = new Spanner (props);
 127   else if (klass == ly_symbol2scm ("Paper_column"))
 128     grob = new Paper_column (props);
 129
 130   assert (grob);
 131   announce_grob (grob, cause);
 132
 133 #ifndef NDEBUG
 134   if (ly_is_procedure (creation_callback))
 135     scm_apply_0 (creation_callback,
 136                  scm_list_n (grob->self_scm (), scm_from_locale_string (file),
 137                              scm_from_int (line), scm_from_locale_string (fun), SCM_UNDEFINED));
 138 #endif
 139
 140   return grob;
 141 }
 142
 143 Item *
 144 Engraver::internal_make_item (SCM x, SCM cause,
 145                               char const *name,
 146                               char const *file, int line, char const *fun)
 147 {
 148   Item *it = dynamic_cast<Item *> (internal_make_grob (x, cause, name, file, line, fun));
 149   assert (it);
 150   return it;
 151 }
 152
 153 Paper_column *
 154 Engraver::internal_make_column (SCM x, char const *name,
 155                                 char const *file, int line, char const *fun)
 156 {
 157   return dynamic_cast<Paper_column *> (internal_make_grob (x, SCM_EOL, name, file, line, fun));
 158 }
 159
 160 Spanner *
 161 Engraver::internal_make_spanner (SCM x, SCM cause, char const *name, char const *file, int line, char const *fun)
 162 {
 163   Spanner *sp = dynamic_cast<Spanner *> (internal_make_grob (x, cause, name, file, line, fun));
 164   assert (sp);
 165   return sp;
 166 }
 167
 168 #include "translator.icc"
 169
 170 ADD_TRANSLATOR (Engraver,
 171                 /* doc */
 172                 "Base class for engravers.  Does nothing, so it is not used.",
 173
 174                 /* create */
 175                 "",
 176
 177                 /* read */
 178                 "",
 179
 180                 /* write */
 181                 ""
 182                 );
 183