--- /dev/null
+/*
+ This file is part of LilyPond, the GNU music typesetter.
+
+ Copyright (C) 2011--2012 Mike Solomon <mike@apollinemike.com>
+
+ LilyPond is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ LilyPond is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with LilyPond. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <algorithm>
+
+#include "align-interface.hh"
+#include "context.hh"
+#include "grob.hh"
+#include "item.hh"
+#include "pointer-group-interface.hh"
+#include "engraver.hh"
+
+/*
+ The Span_bar_stub_engraver creates SpanBarStub grobs in the contexts
+ that a grouping context contains. For example, if a PianoStaff contains
+ two Staffs, a Dynamics, and a Lyrics, SpanBarStubs will be created in
+ all contexts that do not have bar lines (Dynamics and Lyrics).
+
+ We only want to create these SpanBarStubs in contexts that the SpanBar
+ traverses. However, Contexts do not contain layout information and it
+ is thus difficult to know if they will eventually be above or below other
+ Contexts. To determine this we use the VerticalAxisGroup created in the
+ Context. We relate VerticalAxisGroups to Contexts in the variable
+ axis_groups_ and weed out unused contexts after each translation timestep.
+
+ Note that SpanBarStubs exist for pure height calculations ONLY.
+ They should never be visually present on the page and should never
+ be engraved in contexts where BarLines are engraved.
+*/
+
+class Span_bar_stub_engraver : public Engraver
+{
+ vector<Grob *> spanbars_;
+ SCM axis_groups_;
+
+public:
+ TRANSLATOR_DECLARATIONS (Span_bar_stub_engraver);
+protected:
+ DECLARE_ACKNOWLEDGER (span_bar);
+ DECLARE_ACKNOWLEDGER (hara_kiri_group_spanner);
+ void process_acknowledged ();
+ void stop_translation_timestep ();
+ virtual void derived_mark () const;
+};
+
+Span_bar_stub_engraver::Span_bar_stub_engraver ()
+{
+ axis_groups_ = SCM_EOL;
+}
+
+void
+Span_bar_stub_engraver::derived_mark () const
+{
+ scm_gc_mark (axis_groups_);
+}
+
+void
+Span_bar_stub_engraver::acknowledge_span_bar (Grob_info i)
+{
+ spanbars_.push_back (i.grob ());
+}
+
+void
+Span_bar_stub_engraver::acknowledge_hara_kiri_group_spanner (Grob_info i)
+{
+ axis_groups_ = scm_cons (scm_cons (i.grob ()->self_scm (), i.context ()->self_scm ()), axis_groups_);
+}
+
+void
+Span_bar_stub_engraver::process_acknowledged ()
+{
+ if (!spanbars_.size ())
+ return;
+
+ if (!scm_is_pair (axis_groups_))
+ {
+ programming_error ("At least one vertical axis group needs to be created in the first time step.");
+ return;
+ }
+ Grob *vertical_alignment = Grob::get_root_vertical_alignment (unsmob_grob (scm_caar (axis_groups_)));
+ if (!vertical_alignment) // we are at the beginning of a score, so no need for stubs
+ return;
+
+ for (vsize i = 0; i < spanbars_.size (); i++)
+ {
+ extract_grob_set (spanbars_[i], "elements", bars);
+ vector<vsize> bar_axis_indices;
+ for (vsize j = 0; j < bars.size (); j++)
+ {
+ int i = Grob::get_vertical_axis_group_index (bars[j]);
+ if (i >= 0)
+ bar_axis_indices.push_back ((vsize) i);
+ }
+ vector<Context *> affected_contexts;
+ vector<Grob *> y_parents;
+ vector<bool> keep_extent;
+ for (SCM s = axis_groups_; scm_is_pair (s); s = scm_cdr (s))
+ {
+ Context *c = unsmob_context (scm_cdar (s));
+ Grob *g = unsmob_grob (scm_caar (s));
+ if (!c || !g)
+ continue;
+ if (c->is_removable ())
+ continue;
+
+ vsize j = Grob::get_vertical_axis_group_index (g);
+ if (j > bar_axis_indices[0]
+ && j < bar_axis_indices.back ()
+ && find (bar_axis_indices.begin (), bar_axis_indices.end (), j) == bar_axis_indices.end ())
+ {
+ vsize k = 0;
+ for (; k < bar_axis_indices.size (); k++)
+ if (bar_axis_indices[k] > j)
+ break;
+
+ k--;
+
+ if (c && c->get_parent_context ())
+ {
+ keep_extent.push_back (to_boolean (bars[k]->get_property ("allow-span-bar")));
+ y_parents.push_back (g);
+ affected_contexts.push_back (c);
+ }
+ }
+ }
+
+ for (vsize j = 0; j < affected_contexts.size (); j++)
+ {
+ Item *it = new Item (updated_grob_properties (affected_contexts[j], ly_symbol2scm ("SpanBarStub")));
+ it->set_parent (spanbars_[i], X_AXIS);
+ Grob_info gi = make_grob_info (it, spanbars_[i]->self_scm ());
+ gi.rerouting_daddy_context_ = affected_contexts[j];
+ announce_grob (gi);
+ if (!keep_extent[j])
+ it->suicide ();
+ }
+ }
+
+ spanbars_.clear ();
+}
+
+// removes all unused contexts
+void
+Span_bar_stub_engraver::stop_translation_timestep ()
+{
+ SCM axis_groups = SCM_EOL;
+ for (SCM s = axis_groups_; scm_is_pair (s); s = scm_cdr (s))
+ {
+ Context *c = unsmob_context (scm_cdar (s));
+ Grob *g = unsmob_grob (scm_caar (s));
+ if (!c || !g)
+ continue;
+ if (c->is_removable ())
+ continue;
+ axis_groups = scm_cons (scm_car (s), axis_groups);
+ }
+ axis_groups_ = axis_groups;
+}
+
+#include "translator.icc"
+
+ADD_ACKNOWLEDGER (Span_bar_stub_engraver, span_bar);
+ADD_ACKNOWLEDGER (Span_bar_stub_engraver, hara_kiri_group_spanner);
+ADD_TRANSLATOR (Span_bar_stub_engraver,
+ /* doc */
+ "Make stubs for span bars in all contexts that the span bars cross.",
+
+ /* create */
+ "SpanBarStub ",
+
+ /* read */
+ "",
+
+ /* write */
+ ""
+ );
projects / lilypond.git / blobdiff