-/*
- TODO: should a add penalty for widely varying spring forces (caused
- by constraints, eg.
-
-
- . =====
- . | |
- .o|o|x ##x
- .
-
- The ## forces the notes apart; we shouldn't allow the O's to touch
- this closely.
-*/
-
-struct Rod_description
-{
- vsize r_;
- Real dist_;
-
- bool operator< (const Rod_description r)
- {
- return r_ < r.r_;
- }
-
- Rod_description ()
- {
- r_ = 0;
- dist_ = 0;
- }
-
- Rod_description (vsize r, Real d)
- {
- r_ = r;
- dist_ = d;
- }
-};
-
-struct Column_description
-{
- vector<Rod_description> rods_;
- vector<Rod_description> end_rods_; /* use these if they end at the last column of the line */
- Real ideal_;
- Real inverse_hooke_;
- Real end_ideal_;
- Real end_inverse_hooke_;
- SCM break_permission_;
- Interval keep_inside_line_;
-
- Column_description ()
- {
- ideal_ = 0;
- inverse_hooke_ = 0;
- end_ideal_ = 0;
- end_inverse_hooke_ = 0;
- break_permission_ = SCM_EOL;
- }
-};
-
-static bool
-is_loose (Grob *g)
-{
- return (scm_is_pair (g->get_object ("between-cols")));
-}
-
-static Grob*
-maybe_find_prebroken_piece (Grob *g, Direction d)
-{
- Grob *ret = dynamic_cast<Item*> (g)->find_prebroken_piece (d);
- if (ret)
- return ret;
- return g;
-}
-
-static Grob*
-next_spaceable_column (vector<Grob*> const &list, vsize starting)
-{
- for (vsize i = starting+1; i < list.size (); i++)
- if (!is_loose (list[i]))
- return list[i];
- return 0;
-}
-
-static Column_description
-get_column_description (vector<Grob*> const &cols, vsize col_index, bool line_starter)
-{
- Grob *col = cols[col_index];
- if (line_starter)
- col = maybe_find_prebroken_piece (col, RIGHT);
-
- Column_description description;
- Grob *next_col = next_spaceable_column (cols, col_index);
- if (next_col)
- Spaceable_grob::get_spring (col, next_col, &description.ideal_, &description.inverse_hooke_);
- Grob *end_col = dynamic_cast<Item*> (cols[col_index+1])->find_prebroken_piece (LEFT);
- if (end_col)
- Spaceable_grob::get_spring (col, end_col, &description.end_ideal_, &description.end_inverse_hooke_);
-
- for (SCM s = Spaceable_grob::get_minimum_distances (col);
- scm_is_pair (s); s = scm_cdr (s))
- {
- Grob *other = unsmob_grob (scm_caar (s));
- vsize j = binary_search (cols, other, Paper_column::less_than, col_index);
- if (j != VPOS)
- {
- if (cols[j] == other)
- description.rods_.push_back (Rod_description (j, scm_to_double (scm_cdar (s))));
- else /* it must end at the LEFT prebroken_piece */
- description.end_rods_.push_back (Rod_description (j, scm_to_double (scm_cdar (s))));
- }
- }
-
- if (!line_starter && to_boolean (col->get_property ("keep-inside-line")))
- description.keep_inside_line_ = col->extent (col, X_AXIS);
-
- description.break_permission_ = col->get_property ("line-break-permission");
- return description;
-}
-
-vector<Real>
-get_line_forces (vector<Grob*> const &columns,
- Real line_len, Real indent, bool ragged)
-{
- vector<vsize> breaks;
- vector<Real> force;
- vector<Grob*> non_loose;
- vector<Column_description> cols;
- SCM force_break = ly_symbol2scm ("force");
-
- for (vsize i = 0; i < columns.size (); i++)
- if (!is_loose (columns[i]) || Paper_column::is_breakable (columns[i]))
- non_loose.push_back (columns[i]);
-
- breaks.clear ();
- breaks.push_back (0);
- cols.push_back (Column_description ());
- for (vsize i = 1; i < non_loose.size () - 1; i++)
- {
- if (Paper_column::is_breakable (non_loose[i]))
- breaks.push_back (cols.size ());
-
- cols.push_back (get_column_description (non_loose, i, false));
- }
- breaks.push_back (cols.size ());
- force.resize (breaks.size () * breaks.size (), infinity_f);
-
- for (vsize b = 0; b < breaks.size () - 1; b++)
- {
- cols[breaks[b]] = get_column_description (non_loose, breaks[b], true);
- vsize st = breaks[b];
-
- for (vsize c = b+1; c < breaks.size (); c++)
- {
- vsize end = breaks[c];
- Simple_spacer spacer;
-
- for (vsize i = breaks[b]; i < end - 1; i++)
- spacer.add_spring (cols[i].ideal_, cols[i].inverse_hooke_);
- spacer.add_spring (cols[end-1].end_ideal_, cols[end-1].end_inverse_hooke_);
-
-
- for (vsize i = breaks[b]; i < end; i++)
- {
- for (vsize r = 0; r < cols[i].rods_.size (); r++)
- if (cols[i].rods_[r].r_ < end)
- spacer.add_rod (i - st, cols[i].rods_[r].r_ - st, cols[i].rods_[r].dist_);
- for (vsize r = 0; r < cols[i].end_rods_.size (); r++)
- if (cols[i].end_rods_[r].r_ == end)
- spacer.add_rod (i - st, end - st, cols[i].end_rods_[r].dist_);
- if (!cols[i].keep_inside_line_.is_empty ())
- {
- spacer.add_rod (i - st, end - st, cols[i].keep_inside_line_[RIGHT]);
- spacer.add_rod (0, i - st, -cols[i].keep_inside_line_[LEFT]);
- }
- }
- spacer.solve ((b == 0) ? line_len - indent : line_len, ragged);
-
- /* add a (convex) penalty for compression. We do this _only_ in get_line_forces,
- not get_line_configuration. This is temporary, for backwards compatibility;
- the old line/page-breaking stuff ignores page breaks when it calculates line
- breaks, so compression penalties can result in scores (eg. wtk-fugue) blowing
- up to too many pages. */
- Real f = spacer.force ();
- force[b * breaks.size () + c] = f - (f < 0 ? f*f*f*f*4 : 0);
-
- if (!spacer.fits ())
- {
- if (c == b + 1)
- force[b * breaks.size () + c] = -200000;
- else
- force[b * breaks.size () + c] = infinity_f;
- break;
- }
- if (end < cols.size () && cols[end].break_permission_ == force_break)
- break;
- }
- }
- return force;
-}
-