source file of the GNU LilyPond music typesetter
- (c) 1997 Han-Wen Nienhuys <hanwen@stack.nl>
+ (c) 1997--2004 Han-Wen Nienhuys <hanwen@cs.uu.nl>
*/
-#include "debug.hh"
+#include "paper-score.hh"
+#include "warn.hh"
#include "item.hh"
-#include "p-col.hh"
+#include "paper-column.hh"
+#include "spanner.hh"
+#include "lily-guile.hh"
+#include "system.hh"
+#include "group-interface.hh"
-Item::Item()
+Item::Item (SCM s)
+ : Grob (s)
{
- pcol_l_ = 0;
+ broken_to_drul_[LEFT] = broken_to_drul_[RIGHT]=0;
+ Group_interface::add_thing (this, ly_symbol2scm ("interfaces"), ly_symbol2scm ("item-interface"));
+}
+
+/**
+ Item copy ctor. Copy nothing: everything should be a elt property
+ or a special purpose pointer (such as broken_to_drul_[]) */
+Item::Item (Item const &s)
+ : Grob (s)
+{
+ broken_to_drul_[LEFT] = broken_to_drul_[RIGHT] =0;
+}
+
+
+bool
+Item::breakable_b (Grob*me)
+{
+ if (me->original_)
+ return false;
+
+ if (!dynamic_cast<Item*> (me))
+ me->programming_error ("only items can be breakable.");
+
+ Item * i =dynamic_cast<Item*> (me->get_parent (X_AXIS));
+ return (i) ? Item::breakable_b (i) : to_boolean (me->get_grob_property ("breakable"));
+}
+
+Paper_column *
+Item::get_column () const
+{
+ Item *parent = dynamic_cast<Item*> (get_parent (X_AXIS));
+ return parent ? parent->get_column () : 0;
+}
+
+System *
+Item::get_system () const
+{
+ Grob *g = get_parent (X_AXIS);
+ return g ? g->get_system () : 0;
}
-IMPLEMENT_STATIC_NAME(Item);
void
-Item::do_print() const
+Item::copy_breakable_items ()
{
-#ifndef NPRINT
- mtor << "(unknown)";
-#endif
+ Drul_array<Item *> new_copies;
+ Direction i=LEFT;
+ do
+ {
+ Grob * dolly = clone ();
+ Item * item = dynamic_cast<Item*> (dolly);
+ pscore_->system_->typeset_grob (item);
+ new_copies[i] =item;
+ }
+ while (flip (&i) != LEFT);
+ broken_to_drul_= new_copies;
}
-Real
-Item::hpos_f()const
+bool
+Item::broken_b () const
{
- return pcol_l_->hpos + offset().x;
+ return broken_to_drul_[LEFT] || broken_to_drul_[RIGHT];
}
+/*
+ Generate items for begin and end-of line.
+ */
+void
+Item::discretionary_processing ()
+{
+ if (broken_b ())
+ return;
-Line_of_score *
-Item::line_l()const
+ if (Item::breakable_b (this))
+ copy_breakable_items ();
+}
+
+Grob*
+Item::find_broken_piece (System*l) const
{
- return pcol_l_->line_l_;
+ if (get_system () == l)
+ return (Item*) (this);
+
+ Direction d = LEFT;
+ do {
+ Grob *s = broken_to_drul_[d];
+ if (s && s->get_system () == l)
+ return s;
+ }
+ while (flip (&d) != LEFT);
+
+ return 0;
}
+
+
+Item*
+Item::find_prebroken_piece (Direction d) const
+{
+ Item * me = (Item *) (this);
+ if (!d)
+ return me;
+ return dynamic_cast<Item*> (broken_to_drul_[d]);
+}
+
+
+Direction
+Item::break_status_dir () const
+{
+ if (original_)
+ {
+ Item * i = dynamic_cast<Item*> (original_);
+
+ return (i->broken_to_drul_[LEFT] == this) ? LEFT : RIGHT;
+ }
+ else
+ return CENTER;
+}
+
+void
+Item::handle_prebroken_dependencies ()
+{
+ Grob::handle_prebroken_dependencies ();
+
+ /*
+ Can't do this earlier, because try_visibility_lambda () might set
+ the elt property transparent, which would then be copied.
+
+ TODO:
+
+ give the item to break-visibility itself, so the function can do
+ more complicated things.
+ */
+ SCM vis = get_grob_property ("break-visibility");
+ if (gh_procedure_p (vis))
+ {
+ SCM args = scm_list_n (gh_int2scm (break_status_dir ()), SCM_UNDEFINED);
+ SCM result = gh_apply (vis, args);
+ bool trans = gh_scm2bool (ly_car (result));
+ bool empty = gh_scm2bool (ly_cdr (result));
+
+ if (empty && trans)
+ suicide ();
+ else if (empty)
+ {
+ set_extent (SCM_EOL, X_AXIS);
+ set_extent (SCM_EOL, Y_AXIS);
+ }
+ else if (trans)
+ set_grob_property ("molecule-callback", SCM_EOL);
+ }
+}
+
+SCM
+Item::do_derived_mark ()const
+{
+ if (broken_to_drul_[LEFT])
+ scm_gc_mark (broken_to_drul_[LEFT]->self_scm ());
+ if (broken_to_drul_[RIGHT])
+ scm_gc_mark (broken_to_drul_[RIGHT]->self_scm ());
+ return SCM_EOL;
+}
+
+Item*
+unsmob_item (SCM s )
+{
+ return dynamic_cast<Item*> (unsmob_grob (s));
+}
+
+
+
+ADD_INTERFACE(Item,
+ "item-interface",
+ "\n"
+ "\n"
+ "Grobs can be distinguished in their role in the horizontal spacing.\n"
+ "Many grobs define constraints on the spacing by their sizes. For\n"
+ "example, note heads, clefs, stems, and all other symbols with a fixed\n"
+ "shape. These grobs form a subtype called @code{Item}.\n"
+ "\n"
+ "\n"
+ "Some items need special treatment for line breaking. For example, a\n"
+ "clef is normally only printed at the start of a line (i.e. after a\n"
+ "line break). To model this, `breakable' items (clef, key signature,\n"
+ "bar lines, etc.) are copied twice. Then we have three versions of each\n"
+ "breakable item: one version if there is no line break, one version\n"
+ "that is printed before the line break (at the end of a system), one\n"
+ "version that is printed after the line break.\n"
+ "\n"
+ "Whether these versions are visible and take up space, is determined by\n"
+ "the outcome of the @code{break-visibility}. This grob property is a\n"
+ "function taking a direction (-1, 0 or 1) as argument. It returns a\n"
+ "cons of booleans, signifying whether this grob should be transparent\n"
+ "and have no extent.\n"
+ "\n"
+ "The following variables for break-visibility are predefined:\n"
+ "@example\n"
+ " grob will show: before no after\n"
+ " break break break\n"
+ " all-invisible no no no\n"
+ " begin-of-line-visible no no yes\n"
+ " end-of-line-visible yes no no\n"
+ " all-visible yes yes yes\n"
+ " begin-of-line-invisible yes yes no\n"
+ " end-of-line-invisible no yes yes\n"
+ "@end example\n"
+ ,
+ "no-spacing-rods break-visibility breakable")
projects / lilypond.git / blobdiff