2 page-turn-page-breaking.cc -- implement Page_turn_page_breaking
4 source file of the GNU LilyPond music typesetter
6 (c) 2006 Joe Neeman <joeneeman@gmail.com>
9 #include "page-turn-page-breaking.hh"
11 #include "international.hh"
13 #include "output-def.hh"
14 #include "page-spacing.hh"
15 #include "paper-book.hh"
16 #include "paper-score.hh"
17 #include "paper-system.hh"
24 return scm_is_symbol (g->get_property ("page-turn-permission"));
27 Page_turn_page_breaking::Page_turn_page_breaking (Paper_book *pb)
28 : Page_breaking (pb, is_break)
32 Page_turn_page_breaking::~Page_turn_page_breaking ()
37 Page_turn_page_breaking::calc_demerits (const Break_node &me)
41 Real page_weighting = robust_scm2double (book_->paper_->c_variable ("page-spacing-weight"), 1);
44 prev_f = state_[me.prev_].force_;
45 prev_dem = state_[me.prev_].demerits_;
48 Real dem = me.force_ * me.force_ * page_weighting
49 + me.line_force_ * me.line_force_
50 + fabs (me.force_ - prev_f);
51 if (isinf (me.line_force_) || isinf (me.force_))
54 return dem + prev_dem + me.penalty_ + me.line_penalty_;
57 Page_turn_page_breaking::Break_node
58 Page_turn_page_breaking::put_systems_on_pages (vsize start,
60 vector<Line_details> const &lines,
61 Line_division const &div,
64 bool last = end == breaks_.size () - 1;
65 bool ragged_all = to_boolean (book_->paper_->c_variable ("ragged-bottom"));
66 bool ragged_last = last && to_boolean (book_->paper_->c_variable ("ragged-last-bottom"));
67 Real page_h = page_height (1, false); // FIXME
68 SCM force_sym = last ? ly_symbol2scm ("blank-last-page-force") : ly_symbol2scm ("blank-page-force");
69 Real blank_force = robust_scm2double (book_->paper_->lookup_variable (force_sym), 0);
70 Spacing_result result = space_systems_on_min_pages (lines, page_h, blank_force, ragged_all, ragged_last);
73 ret.prev_ = start - 1;
75 ret.first_page_number_ = page_number;
76 ret.page_count_ = result.force_.size ();
78 for (vsize i = 0; i < result.force_.size (); i++)
79 ret.force_ += fabs (result.force_[i]);
81 ret.penalty_ = result.penalty_;
83 ret.system_count_ = result.systems_per_page_;
85 ret.too_many_lines_ = true;
87 ret.line_penalty_ = 0;
88 for (vsize i = 0; i < lines.size (); i++)
90 ret.line_force_ += fabs (lines[i].force_);
91 ret.line_penalty_ += lines[i].break_penalty_;
92 if (lines[i].force_ < 0)
93 ret.too_many_lines_ = false;
99 Page_turn_page_breaking::calc_subproblem (vsize ending_breakpoint)
101 vsize end = ending_breakpoint + 1;
104 Break_node this_start_best;
105 vsize prev_best_system_count = 0;
107 for (vsize start = end; start--;)
110 && breakpoint_property (start+1, "page-turn-permission") == ly_symbol2scm ("force"))
113 if (start > 0 && best.demerits_ < state_[start-1].demerits_)
119 /* if the last node has an odd number of pages and is not the first page,
121 int p_count = state_[start-1].page_count_;
122 int f_p_num = state_[start-1].first_page_number_;
123 p_num = f_p_num + p_count + ((f_p_num > 1) ? p_count % 2 : 0);
126 Line_division min_division;
127 Line_division max_division;
129 vsize min_sys_count = min_system_count (start, end);
130 vsize max_sys_count = max_system_count (start, end);
131 this_start_best.demerits_ = infinity_f;
135 /* heuristic: we've just added a breakpoint, we'll need at least as
136 many systems as before */
137 min_sys_count = max (min_sys_count, prev_best_system_count);
138 for (vsize sys_count = min_sys_count; sys_count <= max_sys_count && ok_page; sys_count++)
140 vector<Line_division> div = line_divisions (start, end, sys_count, min_division, max_division);
143 for (vsize d = 0; d < div.size (); d++)
145 vector<Line_details> line = line_details (start, end, div[d]);
147 cur = put_systems_on_pages (start, end, line, div[d], p_num);
149 if (cur.page_count_ > 2 &&
150 (start < end - 1 || (!isinf (this_start_best.demerits_)
151 && cur.page_count_ + cur.page_count_ % 2
152 > this_start_best.page_count_ + this_start_best.page_count_ % 2)))
157 cur.demerits_ = calc_demerits (cur);
159 if (cur.demerits_ < this_start_best.demerits_)
162 this_start_best = cur;
163 prev_best_system_count = sys_count;
165 /* heuristic: if we increase the number of systems, we can bound the
166 division from below by our current best division */
167 min_division = div[d];
170 if (!found && this_start_best.too_many_lines_)
173 if (isinf (this_start_best.demerits_))
175 assert (!isinf (best.demerits_) && start < end - 1);
178 if (this_start_best.demerits_ < best.demerits_)
179 best = this_start_best;
181 state_.push_back (best);
185 Page_turn_page_breaking::solve ()
188 message (_f ("Calculating page and line breaks (%d possible page breaks)...",
189 (int)breaks_.size () - 1) + " ");
190 for (vsize i = 0; i < breaks_.size () - 1; i++)
193 progress_indication (string ("[") + to_string (i + 1) + "]");
195 progress_indication ("\n");
197 vector<Break_node> breaking;
198 int i = state_.size () - 1;
201 breaking.push_back (state_[i]);
206 message (_ ("Drawing systems..."));
207 SCM systems = make_lines (&breaking);
208 return make_pages (breaking, systems);
211 /* do the line breaking in all the scores and return a big list of systems */
213 Page_turn_page_breaking::make_lines (vector<Break_node> *psoln)
215 vector<Break_node> &soln = *psoln;
216 for (vsize n = 0; n < soln.size (); n++)
218 vsize start = n > 0 ? soln[n-1].break_pos_ : 0;
219 vsize end = soln[n].break_pos_;
221 break_into_pieces (start, end, soln[n].div_);
228 Page_turn_page_breaking::make_pages (vector<Break_node> const &soln, SCM systems)
230 vector<vsize> lines_per_page;
231 for (vsize i = 0; i < soln.size (); i++)
233 for (vsize j = 0; j < soln[i].page_count_; j++)
234 lines_per_page.push_back (soln[i].system_count_[j]);
236 if (i > 0 && i < soln.size () - 1 && soln[i].page_count_ % 2)
237 /* add a blank page */
238 lines_per_page.push_back (0);
240 return Page_breaking::make_pages (lines_per_page, systems);