+/*
+ spacing-determine-loose-columns.cc -- implement Spacing_spanner
+ methods that decide which columns to turn loose.
+
+ source file of the GNU LilyPond music typesetter
+
+ (c) 2005 Han-Wen Nienhuys <hanwen@xs4all.nl>
+
+*/
+
+
+
+#include "system.hh"
+#include "paper-column.hh"
+#include "column-x-positions.hh"
+#include "staff-spacing.hh"
+#include "pointer-group-interface.hh"
+#include "spacing-spanner.hh"
+#include "note-spacing.hh"
+
+#include "break-align-interface.hh"
+
+/*
+ Return whether COL is fixed to its neighbors by some kind of spacing
+ constraint.
+
+
+ If in doubt, then we're not loose; the spacing engine should space
+ for it, risking suboptimal spacing.
+
+ (Otherwise, we might risk core dumps, and other weird stuff.)
+*/
+static bool
+is_loose_column (Grob *l, Grob *c, Grob *r)
+{
+ extract_grob_set (c, "right-neighbors", rns);
+ extract_grob_set (c, "left-neighbors", lns);
+
+ /*
+ If this column doesn't have a proper neighbor, we should really
+ make it loose, but spacing it correctly is more than we can
+ currently can handle.
+
+ (this happens in the following situation:
+
+ |
+ | clef G
+ *
+
+ | | ||
+ | | ||
+ O O ||
+
+
+ the column containing the clef is really loose, and should be
+ attached right to the first column, but that is a lot of work for
+ such a borderline case.)
+
+ */
+ if (lns.is_empty () || rns.is_empty ())
+ return false;
+
+ Item *l_neighbor = dynamic_cast<Item *> (lns[0]);
+ Item *r_neighbor = dynamic_cast<Item *> (rns[0]);
+
+ if (!l_neighbor || !r_neighbor)
+ return false;
+
+ l_neighbor = l_neighbor->get_column ();
+ r_neighbor = dynamic_cast<Item *> (Note_spacing::right_column (r_neighbor));
+
+ if (l == l_neighbor && r == r_neighbor)
+ return false;
+
+ if (!l_neighbor || !r_neighbor)
+ return false;
+
+ /*
+ Only declare loose if the bounds make a little sense. This means
+ some cases (two isolated, consecutive clef changes) won't be
+ nicely folded, but hey, then don't do that.
+ */
+ if (! ((Paper_column::is_musical (l_neighbor) || Item::is_breakable (l_neighbor))
+ && (Paper_column::is_musical (r_neighbor) || Item::is_breakable (r_neighbor))))
+ {
+ return false;
+ }
+
+ /*
+ A rather hairy check, but we really only want to move around
+ clefs. (anything else?)
+
+ in any case, we don't want to move bar lines.
+ */
+ extract_grob_set (c, "elements", elts);
+ for (int i = elts.size (); i--; )
+ {
+ Grob *g = elts[i];
+ if (g && Break_align_interface::has_interface (g))
+ {
+ extract_grob_set (g, "elements", gelts);
+ for (int j = gelts.size (); j--; )
+ {
+ Grob *h = gelts[j];
+
+ /*
+ ugh. -- fix staff-bar name?
+ */
+ if (h && h->get_property ("break-align-symbol") == ly_symbol2scm ("staff-bar"))
+ return false;
+ }
+ }
+ }
+
+ return true;
+}
+
+/*
+ Remove columns that are not tightly fitting from COLS. In the
+ removed columns, set 'between-cols to the columns where it is in
+ between.
+*/
+void
+Spacing_spanner::prune_loose_columns (Grob *me, Link_array<Grob> *cols,
+ Spacing_options const *options)
+{
+ Link_array<Grob> newcols;
+ Real increment = robust_scm2double (me->get_property ("spacing-increment"), 1.2);
+ for (int i = 0; i < cols->size (); i++)
+ {
+ if (Item::is_breakable (cols->elem (i))
+ || Paper_column::is_musical (cols->elem (i)))
+ {
+ newcols.push (cols->elem (i));
+ continue;
+ }
+
+ Grob *c = cols->elem (i);
+ if (is_loose_column (cols->elem (i - 1), c, cols->elem (i + 1)))
+ {
+ extract_grob_set (c, "right-neighbors", rns_arr);
+ extract_grob_set (c, "left-neighbors", lns_arr);
+
+ SCM lns = lns_arr.size () ? lns_arr.top()->self_scm () : SCM_BOOL_F;
+ SCM rns = rns_arr.size () ? rns_arr.top()->self_scm () : SCM_BOOL_F;
+
+ /*
+ Either object can be non existent, if the score ends
+ prematurely.
+ */
+
+ extract_grob_set (unsmob_grob (rns), "right-items", right_items);
+ c->set_object ("between-cols", scm_cons (lns,
+ right_items[0]->self_scm ()));
+
+ /*
+ Set distance constraints for loose columns
+ */
+ Drul_array<Grob *> next_door;
+ next_door[LEFT] = cols->elem (i - 1);
+ next_door[RIGHT] = cols->elem (i + 1);
+ Direction d = LEFT;
+ Drul_array<Real> dists (0, 0);
+
+ do
+ {
+ dists[d] = 0.0;
+ Item *lc = dynamic_cast<Item *> ((d == LEFT) ? next_door[LEFT] : c);
+ Item *rc = dynamic_cast<Item *> (d == LEFT ? c : next_door[RIGHT]);
+
+
+ extract_grob_set (lc, "spacing-wishes", wishes);
+ for (int k = wishes.size(); k--;)
+ {
+ Grob *sp = wishes[k];
+ if (Note_spacing::left_column (sp) != lc
+ || Note_spacing::right_column (sp) != rc)
+ continue;
+
+ Real space, fixed;
+ fixed = 0.0;
+ bool dummy;
+
+ if (d == LEFT)
+ {
+ /*
+ The note spacing should be taken from the musical
+ columns.
+
+ */
+ Real base = note_spacing (me, lc, rc, options, &dummy);
+ Note_spacing::get_spacing (sp, rc, base, increment, &space, &fixed);
+
+ space -= increment;
+
+ dists[d] = max (dists[d], space);
+ }
+ else
+ {
+ Real space, fixed_space;
+ Staff_spacing::get_spacing_params (sp,
+ &space, &fixed_space);
+
+ dists[d] = max (dists[d], fixed_space);
+ }
+ }
+ }
+ while (flip (&d) != LEFT);
+
+ Rod r;
+ r.distance_ = dists[LEFT] + dists[RIGHT];
+ r.item_drul_[LEFT] = dynamic_cast<Item *> (cols->elem (i - 1));
+ r.item_drul_[RIGHT] = dynamic_cast<Item *> (cols->elem (i + 1));
+
+ r.add_to_cols ();
+ }
+ else
+ {
+ newcols.push (c);
+ }
+ }
+
+ *cols = newcols;
+}
+
+/*
+ Set neighboring columns determined by the spacing-wishes grob property.
+*/
+void
+Spacing_spanner::set_explicit_neighbor_columns (Link_array<Grob> const &cols)
+{
+ for (int i = 0; i < cols.size (); i++)
+ {
+ SCM right_neighbors = Grob_array::make_array ();
+ Grob_array *rn_arr = unsmob_grob_array (right_neighbors);
+ int min_rank = 100000; // inf.
+
+ extract_grob_set (cols[i], "spacing-wishes", wishes);
+ for (int k = wishes.size(); k--;)
+ {
+ Item *wish = dynamic_cast<Item *> ( wishes[k]);
+
+ Item *lc = wish->get_column ();
+ Grob *right = Note_spacing::right_column (wish);
+
+ if (!right)
+ continue;
+
+ Item *rc = dynamic_cast<Item *> (right);
+
+ int right_rank = Paper_column::get_rank (rc);
+ int left_rank = Paper_column::get_rank (lc);
+
+ /*
+ update the left column.
+ */
+ if (right_rank <= min_rank)
+ {
+ if (right_rank < min_rank)
+ rn_arr->clear ();
+
+ min_rank = right_rank;
+ rn_arr->add (wish);
+ }
+
+ /*
+ update the right column of the wish.
+ */
+ int maxrank = 0;
+
+ extract_grob_set (rc, "left-neighbors", lns_arr);
+ if (lns_arr.size ())
+ {
+ Item *it = dynamic_cast<Item *> (lns_arr.top());
+ maxrank = Paper_column::get_rank (it->get_column ());
+ }
+
+ if (left_rank >= maxrank)
+ {
+
+ if (left_rank > maxrank)
+ {
+ Grob_array *ga = unsmob_grob_array (rc->get_object ("left-neighbors"));
+ if (ga)
+ ga->clear ();
+ }
+
+ Pointer_group_interface::add_grob (rc, ly_symbol2scm ("left-neighbors"), wish);
+ }
+ }
+
+ if (rn_arr->size ())
+ {
+ cols[i]->set_object ("right-neighbors", right_neighbors);
+ }
+ }
+}
+
+/*
+ Set neighboring columns that have no left/right-neighbor set
+ yet. Only do breakable non-musical columns, and musical columns.
+*/
+void
+Spacing_spanner::set_implicit_neighbor_columns (Link_array<Grob> const &cols)
+{
+ for (int i = 0; i < cols.size (); i++)
+ {
+ Item *it = dynamic_cast<Item *> (cols[i]);
+ if (!Item::is_breakable (it) && !Paper_column::is_musical (it))
+ continue;
+
+ // it->breakable || it->musical
+
+ /*
+ sloppy with typing left/right-neighbors should take list, but paper-column found instead.
+ */
+ extract_grob_set (cols[i], "left-neighbors", lns);
+ if (lns.is_empty () && i )
+ {
+ SCM ga_scm = Grob_array::make_array();
+ Grob_array *ga = unsmob_grob_array (ga_scm);
+ ga->add (cols[i-1]);
+ cols[i]->set_object ("left-neighbors", ga_scm);
+ }
+ extract_grob_set (cols[i], "right-neighbors", rns);
+ if (rns.is_empty () && i < cols.size () - 1)
+ {
+ SCM ga_scm = Grob_array::make_array();
+ Grob_array *ga = unsmob_grob_array (ga_scm);
+ ga->add (cols[i+1]);
+ cols[i]->set_object ("right-neighbors", ga_scm);
+ }
+ }
+}