2 This file is part of LilyPond, the GNU music typesetter.
4 Copyright (C) 2006--2010 Joe Neeman <joeneeman@gmail.com>
6 LilyPond is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or
9 (at your option) any later version.
11 LilyPond is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with LilyPond. If not, see <http://www.gnu.org/licenses/>.
20 #include "international.hh"
21 #include "optimal-page-breaking.hh"
22 #include "output-def.hh"
23 #include "page-spacing.hh"
24 #include "paper-book.hh"
25 #include "paper-score.hh"
29 Optimal_page_breaking::Optimal_page_breaking (Paper_book *pb)
30 : Page_breaking (pb, 0, 0)
34 Optimal_page_breaking::~Optimal_page_breaking ()
38 extern bool debug_page_breaking_scoring;
41 Optimal_page_breaking::solve ()
43 vsize end = last_break_position ();
44 vsize max_sys_count = max_system_count (0, end);
45 vsize first_page_num = robust_scm2int (book_->paper_->c_variable ("first-page-number"), 1);
47 set_to_ideal_line_configuration (0, end);
49 Page_spacing_result best;
50 SCM forced_page_count = book_->paper_->c_variable ("page-count");
51 vsize page_count = robust_scm2int (forced_page_count, 1);
52 Line_division ideal_line_division = current_configuration (0);
53 Line_division best_division = ideal_line_division;
54 vsize min_sys_count = 1;
55 vsize ideal_sys_count = system_count ();
57 if (!scm_is_integer (forced_page_count))
59 /* find out the ideal number of pages */
60 message (_ ("Finding the ideal number of pages..."));
62 best = space_systems_on_best_pages (0, first_page_num);
64 page_count = best.systems_per_page_.size ();
65 ideal_sys_count = best.system_count ();
66 min_sys_count = ideal_sys_count - best.systems_per_page_.back ();
68 if (page_count > 1 && best.systems_per_page_[page_count - 2] > 1)
69 min_sys_count -= best.systems_per_page_[page_count - 2];
71 min_sys_count = max (min_sys_count, (vsize)1);
75 /* TODO: the following line will spit out programming errors if the
76 ideal line spacing doesn't fit on PAGE_COUNT pages */
77 /* TODO: the interaction between systems_per_page and page_count needs to
79 best = space_systems_on_n_pages (0, page_count, first_page_num);
80 min_sys_count = page_count;
84 message (_ ("Fitting music on 1 page..."));
85 else if (scm_is_integer (forced_page_count))
86 message (_f ("Fitting music on %d pages...", (int)page_count));
88 message (_f ("Fitting music on %d or %d pages...", (int)page_count-1, (int)page_count));
90 /* try a smaller number of systems than the ideal number for line breaking */
91 Line_division bound = ideal_line_division;
92 for (vsize sys_count = ideal_sys_count; --sys_count >= min_sys_count;)
94 Page_spacing_result best_for_this_sys_count;
95 set_current_breakpoints (0, end, sys_count, Line_division (), bound);
97 if (debug_page_breaking_scoring)
98 message (_f ("trying %d systems", (int)sys_count));
100 for (vsize i = 0; i < current_configuration_count (); i++)
102 Page_spacing_result cur;
104 if (scm_is_integer (forced_page_count))
105 cur = space_systems_on_n_pages (i, page_count, first_page_num);
107 cur = space_systems_on_best_pages (i, first_page_num);
109 if (cur.demerits_ < best_for_this_sys_count.demerits_)
111 best_for_this_sys_count = cur;
112 bound = current_configuration (i);
116 if (debug_page_breaking_scoring)
117 message (_f ("best score for this sys-count: %f", best_for_this_sys_count.demerits_));
119 if (best_for_this_sys_count.demerits_ < best.demerits_)
121 best = best_for_this_sys_count;
122 best_division = bound;
125 /* Check to see if we already have too few systems. There are two ways
126 we check this: if we are trying one less than the ideal number of pages
127 and the pages are stretched on average then we have too
128 few systems. If the spacing is worse than BAD_SPACING_PENALTY, then we
129 have too few systems. In either case, though, we need to continue reducing
130 the number of systems if max-systems-per-page requires it. */
131 if (!(best.system_count_status_ & SYSTEM_COUNT_TOO_MANY))
133 if (best_for_this_sys_count.page_count () < page_count
134 && best_for_this_sys_count.average_force () > 0)
137 if (best_for_this_sys_count.demerits_ >= BAD_SPACING_PENALTY)
142 /* try a larger number of systems than the ideal line breaking number. This
143 is more or less C&P, but the loop bounds make it difficult to try something
144 like do {...} while (flip(&d) != UP). */
145 bound = ideal_line_division;
146 for (vsize sys_count = ideal_sys_count+1; sys_count <= max_sys_count; sys_count++)
148 Real best_demerits_for_this_sys_count = infinity_f;
149 set_current_breakpoints (0, end, sys_count, bound);
151 if (debug_page_breaking_scoring)
152 message (_f ("trying %d systems", (int)sys_count));
154 for (vsize i = 0; i < current_configuration_count (); i++)
156 vsize min_p_count = min_page_count (i, first_page_num);
157 Page_spacing_result cur;
159 if (min_p_count > page_count)
161 else if (scm_is_integer (forced_page_count))
162 cur = space_systems_on_n_pages (i, page_count, first_page_num);
164 cur = space_systems_on_best_pages (i, first_page_num);
166 if (cur.demerits_ < best.demerits_)
169 best_division = current_configuration (i);
172 if (cur.demerits_ < best_demerits_for_this_sys_count)
174 best_demerits_for_this_sys_count = cur.demerits_;
175 bound = current_configuration (i);
179 if (debug_page_breaking_scoring)
180 message (_f ("best score for this sys-count: %f", best_demerits_for_this_sys_count));
182 if (best_demerits_for_this_sys_count >= BAD_SPACING_PENALTY
183 && !(best.system_count_status_ & SYSTEM_COUNT_TOO_FEW))
187 message (_ ("Drawing systems..."));
188 break_into_pieces (0, end, best_division);
189 SCM lines = systems ();
190 return make_pages (best.systems_per_page_, lines);