/*
- optimal-page-breaking.cc -- implement a page-breaker that
- will break pages in such a way that both horizontal and
- vertical spacing will be acceptable
+ This file is part of LilyPond, the GNU music typesetter.
- source file of the GNU LilyPond music typesetter
+ Copyright (C) 2006--2010 Joe Neeman <joeneeman@gmail.com>
- (c) 2006 Joe Neeman <joeneeman@gmail.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 "international.hh"
#include "optimal-page-breaking.hh"
#include "output-def.hh"
#include "page-spacing.hh"
#include "system.hh"
static bool
-is_break (Grob *g)
+is_break (Grob *)
{
- (void) g; /* shutup warning */
return false;
}
{
}
-Spacing_result
-Optimal_page_breaking::try_page_spacing (Line_division const &line_count)
+extern bool debug_page_breaking_scoring;
+
+SCM
+Optimal_page_breaking::solve ()
{
- vector<Line_details> lines = line_details (0, breaks_.size () - 1, line_count);
- Real page_h = page_height (1, false); // FIXME
- SCM force_sym = ly_symbol2scm ("blank-last-page-force");
- Real blank_force = robust_scm2double (book_->paper_->lookup_variable (force_sym), 0);
- bool ragged_all = book_->paper_->c_variable ("ragged-bottom");
- bool ragged_last = book_->paper_->c_variable ("ragged-last-bottom");
- Spacing_result ret = space_systems_on_best_pages (lines,
- page_h,
- blank_force,
- ragged_all,
- ragged_last);
-
- /* add in the line penalties */
- Real line_force = 0;
- Real line_penalty = 0;
- Real page_weighting = robust_scm2double (book_->paper_->c_variable ("page-spacing-weight"), 1);
-
- for (vsize i = 0; i < lines.size (); i++)
+ vsize end = last_break_position ();
+ vsize max_sys_count = max_system_count (0, end);
+ vsize first_page_num = robust_scm2int (book_->paper_->c_variable ("first-page-number"), 1);
+
+ set_to_ideal_line_configuration (0, end);
+
+ Page_spacing_result best;
+ SCM forced_page_count = book_->paper_->c_variable ("page-count");
+ vsize page_count = robust_scm2int (forced_page_count, 1);
+ Line_division ideal_line_division = current_configuration (0);
+ Line_division best_division = ideal_line_division;
+ vsize min_sys_count = 1;
+ vsize ideal_sys_count = system_count ();
+
+ if (!scm_is_integer (forced_page_count))
+ {
+ /* find out the ideal number of pages */
+ message (_ ("Finding the ideal number of pages..."));
+
+ if (systems_per_page () > 0)
+ best = space_systems_with_fixed_number_per_page (0, first_page_num);
+ else
+ best = space_systems_on_best_pages (0, first_page_num);
+
+ page_count = best.systems_per_page_.size ();
+ ideal_sys_count = best.system_count ();
+ min_sys_count = ideal_sys_count - best.systems_per_page_.back ();
+
+ if (page_count > 1 && best.systems_per_page_[page_count - 2] > 1)
+ min_sys_count -= best.systems_per_page_[page_count - 2];
+
+ min_sys_count = max (min_sys_count, (vsize)1);
+ }
+ else
{
- line_force += fabs (lines[i].force_);
- line_penalty += lines[i].break_penalty_;
+ /* TODO: the following line will spit out programming errors if the
+ ideal line spacing doesn't fit on PAGE_COUNT pages */
+ /* TODO: the interaction between systems_per_page and page_count needs to
+ be considered. */
+ best = space_systems_on_n_pages (0, page_count, first_page_num);
+ min_sys_count = page_count;
}
- ret.demerits_ = ret.force_[0] * ret.force_[0] * page_weighting;
- for (vsize i = 1; i < ret.force_.size (); i++)
+ if (page_count == 1)
+ message (_ ("Fitting music on 1 page..."));
+ else if (scm_is_integer (forced_page_count))
+ message (_f ("Fitting music on %d pages...", (int)page_count));
+ else
+ message (_f ("Fitting music on %d or %d pages...", (int)page_count-1, (int)page_count));
+
+ /* try a smaller number of systems than the ideal number for line breaking */
+ Line_division bound = ideal_line_division;
+ for (vsize sys_count = ideal_sys_count; --sys_count >= min_sys_count;)
{
- Real uniformity = fabs (ret.force_[i] - ret.force_[i-1]);
- ret.demerits_ += (ret.force_[i] * ret.force_[i]
- + uniformity * uniformity) * page_weighting;
+ Page_spacing_result best_for_this_sys_count;
+ set_current_breakpoints (0, end, sys_count, Line_division (), bound);
+
+ if (debug_page_breaking_scoring)
+ message (_f ("trying %d systems", (int)sys_count));
+
+ for (vsize i = 0; i < current_configuration_count (); i++)
+ {
+ vsize min_p_count = min_page_count (i, first_page_num);
+ Page_spacing_result cur;
+
+ if (min_p_count == page_count || scm_is_integer (forced_page_count))
+ cur = space_systems_on_n_pages (i, page_count, first_page_num);
+ else
+ cur = space_systems_on_n_or_one_more_pages (i, page_count-1, first_page_num, 0);
+
+ if (cur.demerits_ < best_for_this_sys_count.demerits_)
+ {
+ best_for_this_sys_count = cur;
+ bound = current_configuration (i);
+ }
+ }
+
+ if (debug_page_breaking_scoring)
+ message (_f ("best score for this sys-count: %f", best_for_this_sys_count.demerits_));
+
+ if (best_for_this_sys_count.demerits_ < best.demerits_)
+ {
+ best = best_for_this_sys_count;
+ best_division = bound;
+ }
+
+ /* Check to see if we already have too few systems. There are two ways
+ we check this: if we are trying one less than the ideal number of pages
+ and the pages are stretched on average then we have too
+ few systems. If the spacing is worse than BAD_SPACING_PENALTY, then we
+ have too few systems. In either case, though, we need to continue reducing
+ the number of systems if max-systems-per-page requires it. */
+ if (!(best.system_count_status_ & SYSTEM_COUNT_TOO_MANY))
+ {
+ if (best_for_this_sys_count.page_count () < page_count
+ && best_for_this_sys_count.average_force () > 0)
+ break;
+
+ if (best_for_this_sys_count.demerits_ >= BAD_SPACING_PENALTY)
+ break;
+ }
}
- ret.demerits_ += line_force + line_penalty;
- return ret;
-}
-SCM
-Optimal_page_breaking::solve ()
-{
- vsize end = breaks_.size () - 1;
- vsize min_sys_count = min_system_count (0, end);
- vsize max_sys_count = max_system_count (0, end);
- vsize max_page_count = INT_MAX;
- vsize cur_page_count = 0;
- Spacing_result best;
- Line_division best_division;
- Line_division lower_bound;
-
- for (vsize sys_count = min_sys_count;
- cur_page_count <= max_page_count && sys_count <= max_sys_count;
- sys_count++)
+ /* try a larger number of systems than the ideal line breaking number. This
+ is more or less C&P, but the loop bounds make it difficult to try something
+ like do {...} while (flip(&d) != UP). */
+ bound = ideal_line_division;
+ for (vsize sys_count = ideal_sys_count+1; sys_count <= max_sys_count; sys_count++)
{
- Real this_best_demerits = infinity_f;
- vector<Line_division> div = line_divisions (0, end, sys_count, lower_bound);
- for (vsize d = 0; d < div.size (); d++)
+ Real best_demerits_for_this_sys_count = infinity_f;
+ set_current_breakpoints (0, end, sys_count, bound);
+
+ if (debug_page_breaking_scoring)
+ message (_f ("trying %d systems", (int)sys_count));
+
+ for (vsize i = 0; i < current_configuration_count (); i++)
{
- Spacing_result cur = try_page_spacing (div[d]);
- cur_page_count = cur.systems_per_page_.size ();
+ vsize min_p_count = min_page_count (i, first_page_num);
+ Page_spacing_result cur;
+
+ if (min_p_count > page_count)
+ continue;
+ else
+ cur = space_systems_on_n_pages (i, page_count, first_page_num);
+
if (cur.demerits_ < best.demerits_)
{
best = cur;
- best_division = div[d];
+ best_division = current_configuration (i);
}
- if (cur.demerits_ < this_best_demerits)
+ if (cur.demerits_ < best_demerits_for_this_sys_count)
{
- this_best_demerits = cur.demerits_;
- lower_bound = div[d];
+ best_demerits_for_this_sys_count = cur.demerits_;
+ bound = current_configuration (i);
}
+ }
- vector<Line_details> det = line_details (0, end, div[d]);
- bool all_lines_stretched = true;
- for (vsize i = 0; i < det.size (); i++)
- if (det[i].force_ < 0)
- all_lines_stretched = false;
+ if (debug_page_breaking_scoring)
+ message (_f ("best score for this sys-count: %f", best_demerits_for_this_sys_count));
- if (all_lines_stretched)
- max_page_count = cur_page_count + 1;
- }
+ if (best_demerits_for_this_sys_count >= BAD_SPACING_PENALTY
+ && !(best.system_count_status_ & SYSTEM_COUNT_TOO_FEW))
+ break;
}
+ message (_ ("Drawing systems..."));
break_into_pieces (0, end, best_division);
SCM lines = systems ();
return make_pages (best.systems_per_page_, lines);