2 This file is part of LilyPond, the GNU music typesetter.
4 Copyright (C) 2006--2009 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 #ifndef CONSTRAINED_BREAKING_HH
21 #define CONSTRAINED_BREAKING_HH
23 #include "lily-guile.hh"
30 Interval extent_; /* Y-extent of the system */
32 Real padding_; /* compulsory space after this system (if we're not
36 Real space_; /* spring length */
39 SCM break_permission_;
48 /* The page-breaker deals with forbidden page breaks by "compressing"
49 two Line_detailses into one. The following fields are used by the
50 page-breaker to keep track of this. If the number of fields needed
51 by the page-breaker grows, it might be a good idea to create a separate
53 int compressed_lines_count_;
54 int compressed_nontitle_lines_count_;
65 break_permission_ = ly_symbol2scm ("allow");
66 page_permission_ = ly_symbol2scm ("allow");
67 turn_permission_ = ly_symbol2scm ("allow");
72 compressed_lines_count_ = 1;
73 compressed_nontitle_lines_count_ = 1;
76 Line_details (Prob *pb, Output_def *paper);
80 Helper to trace back an optimal path
82 struct Constrained_break_node
84 /* the number of bars in all the systems before this one
88 /* unlike the Gourlay breaker, this is the sum of all demerits up to,
89 * and including, this line */
91 struct Line_details details_;
93 Constrained_break_node ()
96 demerits_ = infinity_f;
101 printf ("prev break %d, demerits %f\n", prev_, demerits_);
106 A dynamic programming solution to breaking scores into lines
108 class Constrained_breaking
111 vector<Column_x_positions> solve (vsize start, vsize end, vsize sys_count);
112 vector<Column_x_positions> best_solution (vsize start, vsize end);
113 vector<Line_details> line_details (vsize start, vsize end, vsize sys_count);
115 Constrained_breaking (Paper_score *ps);
116 Constrained_breaking (Paper_score *ps, vector<vsize> const &start_col_posns);
118 int max_system_count (vsize start, vsize end);
119 int min_system_count (vsize start, vsize end);
122 Paper_score *pscore_;
123 vsize valid_systems_;
127 Real between_system_space_;
128 Real before_title_padding_;
129 Real between_system_padding_;
131 /* the (i,j)th entry is the configuration for breaking between
133 Matrix<Line_details> lines_;
135 /* the [i](j,k)th entry is the score for fitting the first k bars onto the
136 first j systems, starting at the i'th allowed starting column */
137 vector<Matrix<Constrained_break_node> > state_;
139 vector<vsize> start_; /* the columns at which we might be asked to start breaking */
140 vector<vsize> starting_breakpoints_; /* the corresponding index in breaks_ */
143 vector<vsize> breaks_;
146 void resize (vsize systems);
148 Column_x_positions space_line (vsize start_col, vsize end_col);
149 vsize prepare_solution (vsize start, vsize end, vsize sys_count);
151 Real combine_demerits (Real force, Real prev_force);
153 bool calc_subproblem (vsize start, vsize systems, vsize max_break_index);
154 void fill_line_details (Line_details *const, vsize, vsize);
156 #endif /* CONSTRAINED_BREAKING_HH */