/*
- 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--2009 Joe Neeman <joeneeman@gmail.com>
- (c) 2006--2007 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"
static bool
is_break (Grob *g)
{
- (void) g; /* shutup warning */
- return false;
+ return g->get_property ("page-break-permission") == ly_symbol2scm ("force");
}
Optimal_page_breaking::Optimal_page_breaking (Paper_book *pb)
{
}
-SCM
-Optimal_page_breaking::solve ()
+extern bool debug_page_breaking_scoring;
+
+// Solves the subproblem betwen the (END-1)th \pageBreak and the
+// ENDth \pageBreak.
+// Returns a vector of systems per page for the pages within this chunk.
+vector<vsize>
+Optimal_page_breaking::solve_chunk (vsize end)
{
- vsize end = breaks_.size () - 1;
- vsize min_sys_count = 0;
- vsize ideal_sys_count = 0;
- vsize max_sys_count = max_system_count (0, end);
- vsize page_count = 0;
- Line_division ideal_line_division;
- Line_division best_division;
- Line_division bound;
+ vsize max_sys_count = max_system_count (end-1, end);
vsize first_page_num = robust_scm2int (book_->paper_->c_variable ("first-page-number"), 1);
+ SCM forced_page_count = book_->paper_->c_variable ("page-count");
+
+ set_to_ideal_line_configuration (end-1, end);
+
+ Page_spacing_result best;
+ 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))
+ {
+ 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
+ {
+ /* 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;
+ }
- /* find out the ideal number of pages */
- message (_ ("Finding the ideal number of pages..."));
- set_to_ideal_line_configuration (0, end);
- ideal_line_division = current_configuration (0);
-
- Spacing_result best = space_systems_on_best_pages (0, first_page_num);
- page_count = best.systems_per_page_.size ();
- best_division = ideal_line_division;
-
- for (vsize i = 0; i < page_count; i++)
- ideal_sys_count += best.systems_per_page_[i];
-
- min_sys_count = ideal_sys_count - best.systems_per_page_.back ();
- if (page_count > 1)
- min_sys_count -= best.systems_per_page_[page_count - 2];
-
- if (page_count == 1)
- message (_ ("Fitting music on 1 page..."));
+ if (page_count == 1 || scm_is_integer (forced_page_count))
+ progress_indication (_f ("[%d: %d pages]", (int) end, (int) page_count));
else
- message (_f ("Fitting music on %d or %d pages...", (int)page_count-1, (int)page_count));
+ progress_indication (_f ("[%d: %d or %d pages]", (int) end, (int) page_count-1, (int)page_count));
/* try a smaller number of systems than the ideal number for line breaking */
- bound = ideal_line_division;
+ Line_division bound = ideal_line_division;
for (vsize sys_count = ideal_sys_count; --sys_count >= min_sys_count;)
{
- Spacing_result best_for_this_sys_count;
- set_current_breakpoints (0, end, sys_count, Line_division (), bound);
+ Page_spacing_result best_for_this_sys_count;
+ set_current_breakpoints (end-1, 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);
- Spacing_result cur;
+ Page_spacing_result cur;
- if (min_p_count > page_count)
- continue;
- else if (min_p_count == page_count)
+ 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);
+ 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_ || isinf (best_for_this_sys_count.demerits_))
+ if (cur.demerits_ < best_for_this_sys_count.demerits_)
{
best_for_this_sys_count = cur;
bound = current_configuration (i);
}
}
- if (best_for_this_sys_count.demerits_ < best.demerits_ || isinf (best.demerits_))
+ 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;
}
- if (best_for_this_sys_count.systems_per_page_.size () < page_count)
+ /* 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 the pages are stretched on average, stop trying to reduce sys_count */
- Real avg_f = 0;
- for (vsize i = 0; i < best_for_this_sys_count.systems_per_page_.size (); i++)
- avg_f += best_for_this_sys_count.systems_per_page_[i];
- if (avg_f > 0)
+ if (best_for_this_sys_count.page_count () < page_count
+ && best_for_this_sys_count.average_force () > 0)
break;
- }
- if (isinf (best_for_this_sys_count.demerits_))
- break;
+ if (best_for_this_sys_count.demerits_ >= BAD_SPACING_PENALTY)
+ break;
+ }
}
/* try a larger number of systems than the ideal line breaking number. This
for (vsize sys_count = ideal_sys_count+1; sys_count <= max_sys_count; sys_count++)
{
Real best_demerits_for_this_sys_count = infinity_f;
- set_current_breakpoints (0, end, sys_count, bound);
+ set_current_breakpoints (end-1, 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++)
{
vsize min_p_count = min_page_count (i, first_page_num);
- Spacing_result cur;
+ 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_ || isinf (best.demerits_))
+ if (cur.demerits_ < best.demerits_)
{
best = cur;
best_division = current_configuration (i);
}
- if (cur.demerits_ < best_demerits_for_this_sys_count || isinf (best_demerits_for_this_sys_count))
+ if (cur.demerits_ < best_demerits_for_this_sys_count)
{
best_demerits_for_this_sys_count = cur.demerits_;
bound = current_configuration (i);
}
}
- if (isinf (best_demerits_for_this_sys_count))
+
+ if (debug_page_breaking_scoring)
+ message (_f ("best score for this sys-count: %f", best_demerits_for_this_sys_count));
+
+ if (best_demerits_for_this_sys_count >= BAD_SPACING_PENALTY
+ && !(best.system_count_status_ & SYSTEM_COUNT_TOO_FEW))
break;
}
+ break_into_pieces (end-1, end, best_division);
+
+ return best.systems_per_page_;
+}
+
+SCM
+Optimal_page_breaking::solve ()
+{
+ vector<vsize> systems_per_page;
+
+ message (_f ("Solving %d page-breaking chunks...", last_break_position ()));
+ for (vsize end = 1; end <= last_break_position (); ++end)
+ {
+ vector<vsize> chunk_systems = solve_chunk (end);
+ systems_per_page.insert (systems_per_page.end (), chunk_systems.begin (), chunk_systems.end ());
+ }
- message ("Drawing systems...");
- break_into_pieces (0, end, best_division);
+ message (_ ("Drawing systems..."));
SCM lines = systems ();
- return make_pages (best.systems_per_page_, lines);
+ return make_pages (systems_per_page, lines);
}