X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=lily%2Fpage-breaking.cc;h=fe1d163658a548f7a59489c348bf3eadb8ea91cf;hb=e90f0536f9be39ada0bef0aeb0d275dec3b2fb5b;hp=a5fe6278d0f99dc8f493b54af07e1425235d65f2;hpb=a8c9e8a7ca320ab0df5fd32e717fd62cd7635ce6;p=lilypond.git diff --git a/lily/page-breaking.cc b/lily/page-breaking.cc index a5fe6278d0..fe1d163658 100644 --- a/lily/page-breaking.cc +++ b/lily/page-breaking.cc @@ -1,21 +1,144 @@ /* - page-breaking.cc -- implement a superclass and utility - functions shared by various page-breaking algorithms + This file is part of LilyPond, the GNU music typesetter. - source file of the GNU LilyPond music typesetter + Copyright (C) 2006--2011 Joe Neeman - (c) 2006--2009 Joe Neeman + 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 . +*/ + +/* + This is a utility class for page-breaking algorithms. There are some complex + parts of this class, some of which are useful to understand if you intend + to write a page breaking algorithm (ie. a subclass of Page_breaking). Most + of these complexities were introduced in order to break the problem of + page-breaking into simpler subproblems and to hide some of the bookkeeping + complexities of page breaking from the page breaking algorithms. + + COMPRESSED LINES + There are several functions that actually distribute systems across pages + (for example, the space_systems_XXX and pack_systems_XXX functions). If + each of these functions had to handle \noPageBreak, it would be a mess. + Therefore, we handle \noPageBreak by "compressing" the list of systems + before doing any layout: we concatenate any two systems separated by a + \noPageBreak into a single system. The page-breaking functions can do their + magic without encountering a \noPageBreak; we then "uncompress" the systems + at the end. We almost always work with cached_line_details_, which are + "compressed." + + CHUNKS + The basic operation of a page breaking algorithm is to repeatedly request + some systems from the line-breaker and place those systems on some pages. + With each repetition, the page breaking algorithm asks the line-breaker for + some systems that it thinks will help it achieve a better layout. The + Page_breaking class provides functionality to facilitate this in the case + that the page breaking algorithm only cares about the number of systems. + + Even if a page breaking algorithm only cares number of systems, there may + be many ways to satisfy its request. For example, in a piece with 2 scores + and a request for 10 systems, we could return 5 systems from each score or + 4 from the first and 6 from the second. Even within a score, we might + want to try several different line breaking configurations with a fixed + system count; if there is a forced \pageBreak, for example, we might wish + to tweak the number of systems on both sides of the \pageBreak independently. + + The Page_breaking class takes care of finding these configurations. It + divides the piece into "chunks" and sets up the line-breaker in such a way + that the number of systems in each chunk can be modified independently. + Chunks never cross score boundaries; each title and markup is its own chunk. + When a page breaking algorithm requests a number of systems, the Page_breaker + stores an array of potential configurations, which the page breaking + algorithm can iterate over using current_configuration(vsize). + + LINE_DIVISION + A Line_division is simply a way of storing the exact way in which the + total number of systems is distributed among chunks. Note that a + Line_division may not (in fact, usually will not) describe all of the chunks + in the entire book. Rather, it will describe the subset of chunks that lie + between some fixed starting and ending point. This subset of chunks changes + whenever a page breaking algorithm asks to consider a different pair of + starting and ending breakpoints. In particular, a Line_division should be + discarded after a call to set_current_breakpoints, since that Line_division + refers to a subset of chunks which might be different from the current + subset of chunks under consideration. + + HOW TO WRITE A PAGE BREAKING ALGORITHM + All page breakers supported by this class work more-or-less in the same way. + First, they request a particular number of systems by saying + set_current_breakpoints (0, last_break_position (), system_count) + (never mind what the first two arguments do, I'll get to them later). + Alternatively, you can do + set_to_ideal_line_configuration (0, last_break_position ()), + and the number of systems will be automatically chosen according to what + the line breaker wants. + + If there are multiple scores, there will be many different ways to achieve + a certain number of lines. You can see how many alternatives are available + with current_configuration_count (). For every i from 0 to + current_configuration_count ()-1, you can see the line division of the + corresponding configuration with current_configuration (i), or you can try + out various page configurations with one of the space_systems_xxx or + pack_systems_xxx functions. The first argument to each of these functions + is the configuration index. + + When you're done trying out configurations and you've picked the one + you want, do + break_into_pieces (0, last_break_position (), line_division_that_you_want); + return make_pages (systems_per_page, systems ()); + where systems_per_page is a vector of numbers telling how many systems are + on each page. You can get your systems_per_page vector by looking inside + the Page_spacing_results that are returned by space_systems_xxx or + pack_systems_xxx. + + A note on performance: set_current_breakpoints is EXPONENTIALLY SLOW unless + you constrain it by giving it a lower or an upper bound on the configurations + it looks for. Optimal_page_breaking, for example, works by trying + out a bunch of configurations, increasing the system count by one, trying + again and so on. Each time we increase the system count, we assume that the + best new configurations are going to be elementwise larger than the + best configuration for the previous system count (in other words, we're going + to get a new configuration just by adding an extra line to sone score + and leaving the rest the same). Therefore, we pass the best previous line + division as an lower bound to set_current_breakpoints. + + Now you should be in a position to understand Optimal_page_breaking::solve. + Go ahead and read that before finding out, in the next paragraph, + what the first two arguments to set_current_breakpoints do. + + "BREAKS" + Sometimes, it's useful to run this whole page-breaking machinery on a subset + of the book. To do this, you can mark certain "breaks" in the book (a poor + choice of name, perhaps, since a "break" here is different from a page break) + and you can run page breaking between any two breaks. You mark your breaks + by providing a Break_predicate (and, if you want, a Prob_break_predicate) + to Page_breaking's constructor. You then choose a subset of your book + by passing the starting and ending breaks to set_current_breakpoints. You + can see an example of this in Page_turn_page_breaking, where there is a break + everywhere that a page turn is allowed. */ #include "page-breaking.hh" #include "international.hh" #include "item.hh" +#include "line-interface.hh" #include "output-def.hh" +#include "page-layout-problem.hh" #include "page-spacing.hh" #include "paper-book.hh" #include "paper-score.hh" #include "paper-system.hh" +#include "text-interface.hh" #include "system.hh" #include "warn.hh" @@ -32,17 +155,37 @@ compress_lines (const vector &orig) { Line_details const &old = ret.back (); Line_details compressed = orig[i]; - compressed.extent_[DOWN] = old.extent_[DOWN]; - compressed.extent_[UP] = old.extent_[UP] + orig[i].extent_.length () + old.padding_; + /* + We must account for the padding between the lines that we are compressing. + The padding values come from "old," which is the upper system here. Note + the meaning of tight-spacing: if a system has tight-spacing, then the padding + _before_ it is ignored. + */ + Real padding = 0; + if (!orig[i].tight_spacing_) + padding = orig[i].title_ ? old.title_padding_ : old.padding_; + + // FIXME: double check these. Doesn't foo.piggyback (bar) mean + // that foo goes on top? + // TODO: break out a Line_details::piggyback from here? + compressed.shape_ = old.shape_.piggyback (orig[i].shape_, padding); + compressed.refpoint_extent_[UP] = old.refpoint_extent_[UP]; + compressed.refpoint_extent_[DOWN] += compressed.shape_.rest_[UP] - old.shape_.rest_[UP]; compressed.space_ += old.space_; compressed.inverse_hooke_ += old.inverse_hooke_; - compressed.title_ = old.title_; - /* we don't need the force_ field for the vertical spacing, - so we use force_ = n to signal that the line was compressed, - reducing the number of lines by n (and force_ = 0 otherwise). - This makes uncompression much easier. */ - compressed.force_ = old.force_ + 1; + compressed.compressed_lines_count_ = old.compressed_lines_count_ + 1; + compressed.compressed_nontitle_lines_count_ = + old.compressed_nontitle_lines_count_ + (compressed.title_ ? 0 : 1); + + // compressed.title_ is true if and only if the first of its + // compressed lines was a title. + compressed.title_ = old.title_; + + // adds footnotes of one line to the footnotes of another + compressed.footnotes_.insert (compressed.footnotes_.begin (), + old.footnotes_.begin (), old.footnotes_.end ()); + ret.back () = compressed; } else @@ -68,7 +211,7 @@ uncompress_solution (vector const &systems_per_page, { int compressed_count = 0; for (vsize j = start_sys; j < start_sys + systems_per_page[i]; j++) - compressed_count += (int)compressed[j].force_; + compressed_count += compressed[j].compressed_lines_count_ - 1; ret.push_back (systems_per_page[i] + compressed_count); start_sys += systems_per_page[i]; @@ -95,15 +238,46 @@ Page_breaking::next_system (Break_position const &break_pos) const return sys + 1; /* this page starts with a new System_spec */ } -Page_breaking::Page_breaking (Paper_book *pb, Break_predicate is_break) +Page_breaking::Page_breaking (Paper_book *pb, Break_predicate is_break, Prob_break_predicate prob_break) { book_ = pb; system_count_ = 0; + paper_height_ = robust_scm2double (pb->paper_->c_variable ("paper-height"), 1.0); ragged_ = to_boolean (pb->paper_->c_variable ("ragged-bottom")); ragged_last_ = to_boolean (pb->paper_->c_variable ("ragged-last-bottom")); - page_top_space_ = robust_scm2double (pb->paper_->c_variable ("page-top-space"), 0); + systems_per_page_ = max (0, robust_scm2int (pb->paper_->c_variable ("systems-per-page"), 0)); + max_systems_per_page_ = max (0, robust_scm2int (pb->paper_->c_variable ("max-systems-per-page"), 0)); + min_systems_per_page_ = max (0, robust_scm2int (pb->paper_->c_variable ("min-systems-per-page"), 0)); + orphan_penalty_ = robust_scm2int (pb->paper_->c_variable ("orphan-penalty"), 100000); + + Stencil *footnote_separator = Page_layout_problem::get_footnote_separator_stencil (pb->paper_); + + if (footnote_separator) + { + Interval separator_extent = footnote_separator->extent (Y_AXIS); + Real separator_span = separator_extent.length (); + + footnote_separator_stencil_height_ = separator_span; + } + else + footnote_separator_stencil_height_ = 0.0; + + footnote_padding_ = robust_scm2double (pb->paper_->c_variable ("footnote-padding"), 0.0); + footnote_footer_padding_ = robust_scm2double (pb->paper_->c_variable ("footnote-footer-padding"), 0.0); + + if (systems_per_page_ && (max_systems_per_page_ || min_systems_per_page_)) + { + warning (_f ("ignoring min-systems-per-page and max-systems-per-page because systems-per-page was set")); + min_systems_per_page_ = max_systems_per_page_ = 0; + } + if (max_systems_per_page_ && min_systems_per_page_ > max_systems_per_page_) + { + warning (_f ("min-systems-per-page is larger than max-systems-per-page, ignoring both values")); + min_systems_per_page_ = max_systems_per_page_ = 0; + } + create_system_list (); - find_chunks_and_breaks (is_break); + find_chunks_and_breaks (is_break, prob_break); } Page_breaking::~Page_breaking () @@ -122,10 +296,26 @@ Page_breaking::ragged_last () const return ragged_last_; } -Real -Page_breaking::page_top_space () const +int +Page_breaking::systems_per_page () const +{ + return systems_per_page_; +} + +int +Page_breaking::max_systems_per_page () const { - return page_top_space_; + if (systems_per_page_) + return systems_per_page_; + return max_systems_per_page_; +} + +int +Page_breaking::min_systems_per_page () const +{ + if (systems_per_page_) + return systems_per_page_; + return min_systems_per_page_; } vsize @@ -134,6 +324,58 @@ Page_breaking::system_count () const return system_count_; } +Real +Page_breaking::footnote_separator_stencil_height () const +{ + return footnote_separator_stencil_height_; +} + +Real +Page_breaking::footnote_padding () const +{ + return footnote_padding_; +} + +Real +Page_breaking::footnote_footer_padding () const +{ + return footnote_footer_padding_; +} + +bool +Page_breaking::too_many_lines (int line_count) const +{ + return max_systems_per_page () > 0 && line_count > max_systems_per_page (); +} + +bool +Page_breaking::too_few_lines (int line_count) const +{ + return line_count < min_systems_per_page (); +} + +Real +Page_breaking::line_count_penalty (int line_count) const +{ + if (too_many_lines (line_count)) + return (line_count - max_systems_per_page ()) * TERRIBLE_SPACING_PENALTY; + if (too_few_lines (line_count)) + return (min_systems_per_page () - line_count) * TERRIBLE_SPACING_PENALTY; + + return 0; +} + +int +Page_breaking::line_count_status (int line_count) const +{ + if (too_many_lines (line_count)) + return SYSTEM_COUNT_TOO_MANY; + if (too_few_lines (line_count)) + return SYSTEM_COUNT_TOO_FEW; + + return SYSTEM_COUNT_OK; +} + /* translate indices into breaks_ into start-end parameters for the line breaker */ void Page_breaking::line_breaker_args (vsize sys, @@ -199,9 +441,8 @@ Page_breaking::systems () ->get_broken_system_grobs (); ret = scm_cons (lines, ret); } - else + else if (Prob *pb = system_specs_[sys].prob_) { - Prob *pb = system_specs_[sys].prob_; ret = scm_cons (scm_list_1 (pb->self_scm ()), ret); pb->unprotect (); } @@ -209,25 +450,62 @@ Page_breaking::systems () return scm_append (scm_reverse (ret)); } -Real -Page_breaking::page_height (int page_num, bool last) const +SCM +Page_breaking::make_page (int page_num, bool last) const { bool last_part = ly_scm2bool (book_->paper_->c_variable ("is-last-bookpart")); SCM mod = scm_c_resolve_module ("scm page"); - SCM calc_height = scm_c_module_lookup (mod, "calc-printable-height"); - SCM make_page = scm_c_module_lookup (mod, "make-page"); - - calc_height = scm_variable_ref (calc_height); - make_page = scm_variable_ref (make_page); - - SCM page = scm_apply_0 (make_page, scm_list_n ( - book_->self_scm (), - ly_symbol2scm ("page-number"), scm_from_int (page_num), - ly_symbol2scm ("is-last-bookpart"), scm_from_bool (last_part), - ly_symbol2scm ("is-bookpart-last-page"), scm_from_bool (last), - SCM_UNDEFINED)); - SCM height = scm_apply_1 (calc_height, page, SCM_EOL); - return scm_to_double (height) - page_top_space_; + SCM make_page_scm = scm_c_module_lookup (mod, "make-page"); + + make_page_scm = scm_variable_ref (make_page_scm); + + return scm_apply_0 (make_page_scm, + scm_list_n (book_->self_scm (), + ly_symbol2scm ("page-number"), scm_from_int (page_num), + ly_symbol2scm ("is-last-bookpart"), scm_from_bool (last_part), + ly_symbol2scm ("is-bookpart-last-page"), scm_from_bool (last), + SCM_UNDEFINED)); +} + +// Returns the total height of the paper, including margins and +// space for the header/footer. This is an upper bound on +// page_height, and it doesn't depend on the current page. +Real +Page_breaking::paper_height () const +{ + return paper_height_; +} + +Real +Page_breaking::page_height (int page_num, bool last) const +{ + // The caches allow us to store the page heights for any + // non-negative page numbers. We use a negative value in the + // cache to signal that that position has not yet been initialized. + // This means that we won't cache properly if page_num is negative or + // if calc_height returns a negative number. But that's likely to + // be rare, so it shouldn't affect performance. + vector& cache = last ? last_page_height_cache_ : page_height_cache_; + if (page_num >= 0 && (int) cache.size () > page_num && cache[page_num] >= 0) + return cache[page_num]; + else + { + SCM mod = scm_c_resolve_module ("scm page"); + SCM page = make_page (page_num, last); + SCM calc_height = scm_c_module_lookup (mod, "calc-printable-height"); + calc_height = scm_variable_ref (calc_height); + + SCM height_scm = scm_apply_1 (calc_height, page, SCM_EOL); + Real height = scm_to_double (height_scm); + + if (page_num >= 0) + { + if ((int) cache.size () <= page_num) + cache.resize (page_num + 1, -1); + cache[page_num] = height; + } + return height; + } } SCM @@ -243,38 +521,96 @@ Page_breaking::breakpoint_property (vsize breakpoint, char const *str) } SCM -Page_breaking::make_pages (vector lines_per_page, SCM systems) +Page_breaking::get_page_configuration (SCM systems, int page_num, bool ragged, bool last) { - SCM layout_module = scm_c_resolve_module ("scm layout-page-layout"); - SCM page_module = scm_c_resolve_module ("scm page"); + SCM dummy_page = make_page (page_num, last); + Page_layout_problem layout (book_, dummy_page, systems); + return scm_is_pair (systems) ? layout.solution (ragged) : SCM_EOL; +} - SCM make_page = scm_c_module_lookup (layout_module, "stretch-and-draw-page"); +SCM +Page_breaking::draw_page (SCM systems, SCM configuration, int page_num, bool last) +{ + // Create a stencil for each system. + SCM paper_systems = SCM_EOL; + for (SCM s = scm_reverse (systems); scm_is_pair (s); s = scm_cdr (s)) + { + SCM paper_system = scm_car (s); + if (Grob *g = unsmob_grob (scm_car (s))) + { + System *sys = dynamic_cast (g); + paper_system = sys->get_paper_system (); + } + + paper_systems = scm_cons (paper_system, paper_systems); + } + + // Create the page and draw it. + SCM page = make_page (page_num, last); + SCM page_module = scm_c_resolve_module ("scm page"); SCM page_stencil = scm_c_module_lookup (page_module, "page-stencil"); - make_page = scm_variable_ref (make_page); page_stencil = scm_variable_ref (page_stencil); - SCM book = book_->self_scm (); + Prob *p = unsmob_prob (page); + p->set_property ("lines", paper_systems); + p->set_property ("configuration", configuration); + + Stencil *foot = unsmob_stencil (p->get_property ("foot-stencil")); + SCM footnotes = Page_layout_problem::get_footnotes_from_lines (systems, footnote_padding ()); + Page_layout_problem::add_footnotes_to_footer (footnotes, foot, unsmob_paper_book (p->get_property ("paper-book"))); + + p->set_property ("foot-stencil", foot->smobbed_copy ()); + scm_apply_1 (page_stencil, page, SCM_EOL); + + return page; +} + +SCM +Page_breaking::make_pages (vector lines_per_page, SCM systems) +{ + if (scm_is_null (systems)) + return SCM_EOL; + int first_page_number = robust_scm2int (book_->paper_->c_variable ("first-page-number"), 1); - bool last_bookpart = ly_scm2bool (book_->paper_->c_variable ("is-last-bookpart")); SCM ret = SCM_EOL; SCM label_page_table = book_->top_paper ()->c_variable ("label-page-table"); if (label_page_table == SCM_UNDEFINED) label_page_table = SCM_EOL; + // Build a list of (systems . configuration) pairs. Note that we lay out + // the staves and find the configurations before drawing anything. Some + // grobs (like tuplet brackets) look at their neighbours while drawing + // themselves. If this happens before the neighbouring staves have + // been laid out, bad side-effects could happen (in particular, + // Align_interface::align_to_ideal_distances might be called). + SCM systems_and_configs = SCM_EOL; + for (vsize i = 0; i < lines_per_page.size (); i++) { - SCM page_num = scm_from_int (i + first_page_number); - bool partbook_last_page = (i == lines_per_page.size () - 1); - SCM rag = scm_from_bool (ragged () || ( partbook_last_page && ragged_last ())); + int page_num = i + first_page_number; + bool bookpart_last_page = (i == lines_per_page.size () - 1); + bool rag = ragged () || (bookpart_last_page && ragged_last ()); SCM line_count = scm_from_int (lines_per_page[i]); SCM lines = scm_list_head (systems, line_count); - SCM page = scm_apply_0 (make_page, - scm_list_n (book, lines, page_num, rag, - scm_from_bool (last_bookpart), - scm_from_bool (partbook_last_page), - SCM_UNDEFINED)); + SCM config = get_page_configuration (lines, page_num, rag, bookpart_last_page); + + systems_and_configs = scm_cons (scm_cons (lines, config), systems_and_configs); + systems = scm_list_tail (systems, line_count); + } + + // Now it's safe to make the pages. + int page_num = first_page_number + lines_per_page.size () - 1; + for (SCM s = systems_and_configs; scm_is_pair (s); s = scm_cdr (s)) + { + SCM lines = scm_caar (s); + SCM config = scm_cdar (s); + + bool bookpart_last_page = (s == systems_and_configs); + SCM page = draw_page (lines, config, page_num, bookpart_last_page); + /* collect labels */ + SCM page_num_scm = scm_from_int (page_num); for (SCM l = lines ; scm_is_pair (l) ; l = scm_cdr (l)) { SCM labels = SCM_EOL; @@ -287,16 +623,19 @@ Page_breaking::make_pages (vector lines_per_page, SCM systems) labels = prob->get_property ("labels"); for (SCM lbls = labels ; scm_is_pair (lbls) ; lbls = scm_cdr (lbls)) - label_page_table = scm_cons (scm_cons (scm_car (lbls), page_num), + label_page_table = scm_cons (scm_cons (scm_car (lbls), page_num_scm), label_page_table); } - scm_apply_1 (page_stencil, page, SCM_EOL); ret = scm_cons (page, ret); - systems = scm_list_tail (systems, line_count); + --page_num; } + + // By reversing the table, we ensure that duplicated labels (eg. those + // straddling a page turn) will appear in the table with their last + // occurence first. + label_page_table = scm_reverse_x (label_page_table, SCM_EOL); book_->top_paper ()->set_variable (ly_symbol2scm ("label-page-table"), label_page_table); - ret = scm_reverse (ret); return ret; } @@ -316,14 +655,7 @@ Page_breaking::create_system_list () { if (Paper_score *ps = dynamic_cast (unsmob_music_output (scm_car (s)))) { - SCM system_count = ps->layout ()->c_variable ("system-count"); - - if (scm_is_number (system_count)) - s = scm_append (scm_list_3 (scm_list_1 (scm_car (s)), - scm_vector_to_list (ps->get_paper_systems ()), - scm_cdr (s))); - else - system_specs_.push_back (System_spec (ps)); + system_specs_.push_back (System_spec (ps)); } else { @@ -334,10 +666,12 @@ Page_breaking::create_system_list () system_specs_.push_back (System_spec (pb)); } } + if (!system_specs_.size ()) + system_specs_.push_back (System_spec ()); } void -Page_breaking::find_chunks_and_breaks (Break_predicate is_break) +Page_breaking::find_chunks_and_breaks (Break_predicate is_break, Prob_break_predicate prob_is_break) { SCM force_sym = ly_symbol2scm ("force"); @@ -348,35 +682,72 @@ Page_breaking::find_chunks_and_breaks (Break_predicate is_break) { if (system_specs_[i].pscore_) { - vector cols - = system_specs_[i].pscore_->root_system ()->used_columns (); + vector cols = system_specs_[i].pscore_->root_system ()->used_columns (); + vector forced_line_break_cols; + + SCM system_count = system_specs_[i].pscore_->layout ()->c_variable ("system-count"); + if (scm_is_number (system_count)) + { + // With system-count given, the line configuration for + // this score is fixed. We need to ensure that chunk + // boundaries only occur at line breaks. + Constrained_breaking breaking (system_specs_[i].pscore_); + vector details = breaking.line_details (0, VPOS, scm_to_int (system_count)); + + for (vsize j = 0; j < details.size (); j++) + forced_line_break_cols.push_back (details[j].last_column_); + } + + int last_forced_line_break_idx = 0; + vsize forced_line_break_idx = 0; vector line_breaker_columns; line_breaker_columns.push_back (0); for (vsize j = 1; j < cols.size (); j++) { + if (forced_line_break_cols.size ()) + { + if (forced_line_break_idx >= forced_line_break_cols.size () + || forced_line_break_cols[forced_line_break_idx] != cols[j]) + continue; + else + forced_line_break_idx++; + } + bool last = (j == cols.size () - 1); - bool break_point = is_break (cols[j]); + bool break_point = is_break && is_break (cols[j]); bool chunk_end = cols[j]->get_property ("page-break-permission") == force_sym; Break_position cur_pos = Break_position (i, line_breaker_columns.size (), cols[j], last); + // NOTE: even in the breaks_ list, forced_line_count_ + // refers to the number of lines between a + // Break_position and the start of that /chunk/. This + // is needed for system_count_bounds to work correctly, + // since it mixes Break_positions from breaks_ and + // chunks_. + if (scm_is_number (system_count)) + cur_pos.forced_line_count_ = forced_line_break_idx - last_forced_line_break_idx; + if (break_point || (i == system_specs_.size () - 1 && last)) breaks_.push_back (cur_pos); if (chunk_end || last) - chunks_.push_back (cur_pos); + { + chunks_.push_back (cur_pos); + last_forced_line_break_idx = forced_line_break_idx; + } if ((break_point || chunk_end) && !last) line_breaker_columns.push_back (j); } line_breaking_.push_back (Constrained_breaking (system_specs_[i].pscore_, line_breaker_columns)); } - else + else if (system_specs_[i].prob_) { - /* TODO: we want some way of applying Break_p to a prob? */ - if (i == system_specs_.size () - 1) + bool break_point = prob_is_break && prob_is_break (system_specs_[i].prob_); + if (break_point || i == system_specs_.size () - 1) breaks_.push_back (Break_position (i)); chunks_.push_back (Break_position (i)); @@ -406,6 +777,7 @@ Page_breaking::chunk_list (vsize start_index, vsize end_index) return ret; } +// Returns the minimum number of _non-title_ lines. vsize Page_breaking::min_system_count (vsize start, vsize end) { @@ -418,6 +790,7 @@ Page_breaking::min_system_count (vsize start, vsize end) return ret; } +// Returns the maximum number of _non-title_ lines. vsize Page_breaking::max_system_count (vsize start, vsize end) { @@ -430,6 +803,9 @@ Page_breaking::max_system_count (vsize start, vsize end) return ret; } +// The numbers returned by this function represent either +// the maximum or minimum number of _non-title_ lines +// per chunk. Page_breaking::Line_division Page_breaking::system_count_bounds (vector const &chunks, bool min) @@ -437,12 +813,15 @@ Page_breaking::system_count_bounds (vector const &chunks, assert (chunks.size () >= 2); Line_division ret; - ret.resize (chunks.size () - 1, 1); + ret.resize (chunks.size () - 1, 0); for (vsize i = 0; i + 1 < chunks.size (); i++) { vsize sys = next_system (chunks[i]); - if (system_specs_[sys].pscore_) + + if (chunks[i+1].forced_line_count_) + ret[i] = chunks[i+1].forced_line_count_; + else if (system_specs_[sys].pscore_) { vsize start; vsize end; @@ -525,13 +904,16 @@ Page_breaking::set_to_ideal_line_configuration (vsize start, vsize end) for (vsize i = 0; i+1 < current_chunks_.size (); i++) { vsize sys = next_system (current_chunks_[i]); - if (system_specs_[sys].pscore_) + + if (current_chunks_[i+1].forced_line_count_) + div.push_back (current_chunks_[i+1].forced_line_count_); + else if (system_specs_[sys].pscore_) { line_breaker_args (sys, current_chunks_[i], current_chunks_[i+1], &start, &end); div.push_back (line_breaking_[sys].best_solution (start, end).size ()); } else - div.push_back (1); + div.push_back (0); system_count_ += div.back (); } @@ -551,10 +933,6 @@ Page_breaking::cache_line_details (vsize configuration_index) if (cached_configuration_index_ != configuration_index) { cached_configuration_index_ = configuration_index; - SCM padding_scm = book_->paper_->c_variable ("page-breaking-between-system-padding"); - if (!scm_is_number (padding_scm)) - padding_scm = book_->paper_->c_variable ("between-system-padding"); - Real padding = robust_scm2double (padding_scm, 0.0); Line_division &div = current_configurations_[configuration_index]; uncompressed_line_details_.clear (); @@ -572,14 +950,14 @@ Page_breaking::cache_line_details (vsize configuration_index) } else { - assert (div[i] == 1); - uncompressed_line_details_.push_back (Line_details (system_specs_[sys].prob_)); - uncompressed_line_details_.back ().padding_ = - robust_scm2double (system_specs_[sys].prob_->get_property ("next-padding"), - padding); + assert (div[i] == 0); + uncompressed_line_details_.push_back (system_specs_[sys].prob_ + ? Line_details (system_specs_[sys].prob_, book_->paper_) + : Line_details ()); } } cached_line_details_ = compress_lines (uncompressed_line_details_); + compute_line_heights (); } } @@ -598,19 +976,19 @@ Page_breaking::line_divisions_rec (vsize system_count, Line_division *cur_division) { vsize my_index = cur_division->size (); - vsize others_min = 0; - vsize others_max = 0; + int others_min = 0; + int others_max = 0; for (vsize i = my_index + 1; i < min_sys.size (); i++) { others_min += min_sys[i]; others_max += max_sys[i]; } - others_max = min (others_max, system_count); - vsize real_min = max (min_sys[my_index], system_count - others_max); - vsize real_max = min (max_sys[my_index], system_count - others_min); + others_max = min (others_max, (int) system_count); + int real_min = max ((int) min_sys[my_index], (int) system_count - others_max); + int real_max = min ((int) max_sys[my_index], (int) system_count - others_min); - if (real_min > real_max || real_min <= 0) + if (real_min > real_max || real_min < 0) { /* this should never happen within a recursive call. If it happens at all, it means that we were called with an unsolvable problem @@ -619,7 +997,7 @@ Page_breaking::line_divisions_rec (vsize system_count, return; } - for (vsize i = real_min; i <= real_max; i++) + for (int i = real_min; i <= real_max; i++) { cur_division->push_back (i); if (my_index == min_sys.size () - 1) @@ -630,37 +1008,104 @@ Page_breaking::line_divisions_rec (vsize system_count, } } +void +Page_breaking::compute_line_heights () +{ + Real prev_hanging = 0; + Real prev_hanging_begin = 0; + Real prev_hanging_rest = 0; + + // refpoint_hanging is the y coordinate of the origin of this system. + // It may not be the same as refpoint_extent[UP], which is the + // refpoint of the first spaceable staff in this system. + Real prev_refpoint_hanging = 0; + for (vsize i = 0; i < cached_line_details_.size (); i++) + { + Line_details& cur = cached_line_details_[i]; + Line_shape shape = cur.shape_; + Real a = shape.begin_[UP]; + Real b = shape.rest_[UP]; + bool title = cur.title_; + Real refpoint_hanging = max (prev_hanging_begin + a, prev_hanging_rest + b); + + if (i > 0) + { + Real padding = 0; + Line_details const& prev = cached_line_details_[i-1]; + if (!cur.tight_spacing_) + padding = title + ? prev.title_padding_ + : prev.padding_; + Real min_dist = title + ? prev.title_min_distance_ + : prev.min_distance_; + refpoint_hanging = max (refpoint_hanging + padding, + prev_refpoint_hanging - prev.refpoint_extent_[DOWN] + + cur.refpoint_extent_[UP] + min_dist); + } + + Real hanging_begin = refpoint_hanging - shape.begin_[DOWN]; + Real hanging_rest = refpoint_hanging - shape.rest_[DOWN]; + Real hanging = max (hanging_begin, hanging_rest); + cur.tallness_ = hanging - prev_hanging; + prev_hanging = hanging; + prev_hanging_begin = hanging_begin; + prev_hanging_rest = hanging_rest; + prev_refpoint_hanging = refpoint_hanging; + } +} + vsize Page_breaking::min_page_count (vsize configuration, vsize first_page_num) { vsize ret = 1; + vsize page_starter = 0; Real cur_rod_height = 0; Real cur_spring_height = 0; Real cur_page_height = page_height (first_page_num, false); + int line_count = 0; cache_line_details (configuration); - for (vsize i = 0; i < cached_line_details_.size (); i++) - { - Real ext_len = cached_line_details_[i].extent_.length (); - Real next_rod_height = cur_rod_height + ext_len - + ((cur_rod_height > 0) ? cached_line_details_[i].padding_: 0); - Real next_spring_height = cur_spring_height + cached_line_details_[i].space_; - Real next_height = next_rod_height + (ragged () ? next_spring_height : 0); + if (cached_line_details_.size ()) + cur_page_height -= min_whitespace_at_top_of_page (cached_line_details_[0]); - if ((next_height > cur_page_height && cur_rod_height > 0) - || (i > 0 - && cached_line_details_[i-1].page_permission_ == ly_symbol2scm ("force"))) + for (vsize i = 0; i < cached_line_details_.size (); i++) + { + Line_details const &cur = cached_line_details_[i]; + Line_details const *const prev = (i > 0) ? &cached_line_details_[i-1] : 0; + Real ext_len; + if (cur_rod_height > 0) + ext_len = cur.tallness_; + else + ext_len = cur.full_height(); + + Real spring_len = (i > 0) ? prev->spring_length (cur) : 0; + Real next_rod_height = cur_rod_height + ext_len; + Real next_spring_height = cur_spring_height + spring_len; + Real next_height = next_rod_height + (ragged () ? next_spring_height : 0) + + min_whitespace_at_bottom_of_page (cur); + int next_line_count = line_count + cur.compressed_nontitle_lines_count_; + + if ((!too_few_lines (line_count) && (next_height > cur_page_height && cur_rod_height > 0)) + || too_many_lines (next_line_count) + || (prev && prev->page_permission_ == ly_symbol2scm ("force"))) { - cur_rod_height = ext_len; - cur_spring_height = cached_line_details_[i].space_; + line_count = cur.compressed_nontitle_lines_count_; + cur_rod_height = cur.full_height(); + cur_spring_height = 0; + page_starter = i; + cur_page_height = page_height (first_page_num + ret, false); + cur_page_height -= min_whitespace_at_top_of_page (cur); + ret++; } else { cur_rod_height = next_rod_height; cur_spring_height = next_spring_height; + line_count = next_line_count; } } @@ -677,22 +1122,39 @@ Page_breaking::min_page_count (vsize configuration, vsize first_page_num) calculations that treated it as a non-last page were ok. */ - cur_page_height = page_height (first_page_num + ret - 1, true); - Real cur_height = cur_rod_height + ((ragged_last () || ragged ()) ? cur_spring_height : 0); - if (cur_height > cur_page_height - /* don't increase the page count if the last page had only one system */ - && cur_rod_height > cached_line_details_.back ().extent_.length ()) - ret++; + if (is_last ()) + { + cur_page_height = page_height (first_page_num + ret - 1, true); + cur_page_height -= min_whitespace_at_top_of_page (cached_line_details_[page_starter]); + cur_page_height -= min_whitespace_at_bottom_of_page (cached_line_details_.back ()); + + Real cur_height = cur_rod_height + ((ragged_last () || ragged ()) ? cur_spring_height : 0); + if (!too_few_lines (line_count - cached_line_details_.back ().compressed_nontitle_lines_count_) + && cur_height > cur_page_height + /* don't increase the page count if the last page had only one system */ + && cur_rod_height > cached_line_details_.back ().full_height ()) + ret++; + assert (ret <= cached_line_details_.size ()); + } - assert (ret <= cached_line_details_.size ()); return ret; } +// If systems_per_page_ is positive, we don't really try to space on N pages; +// we just put the requested number of systems on each page and penalize +// if the result doesn't have N pages. Page_spacing_result Page_breaking::space_systems_on_n_pages (vsize configuration, vsize n, vsize first_page_num) { Page_spacing_result ret; + if (systems_per_page_ > 0) + { + Page_spacing_result ret = space_systems_with_fixed_number_per_page (configuration, first_page_num); + ret.demerits_ += (ret.force_.size () == n) ? 0 : BAD_SPACING_PENALTY; + return ret; + } + cache_line_details (configuration); bool valid_n = (n >= min_page_count (configuration, first_page_num) && n <= cached_line_details_.size ()); @@ -734,12 +1196,22 @@ Page_breaking::blank_page_penalty () const return robust_scm2double (book_->paper_->lookup_variable (penalty_sym), 0.0); } +// If systems_per_page_ is positive, we don't really try to space on N +// or N+1 pages; see the comment to space_systems_on_n_pages. Page_spacing_result -Page_breaking::space_systems_on_n_or_one_more_pages (vsize configuration, vsize n, vsize first_page_num) +Page_breaking::space_systems_on_n_or_one_more_pages (vsize configuration, vsize n, vsize first_page_num, + Real penalty_for_fewer_pages) { Page_spacing_result n_res; Page_spacing_result m_res; + if (systems_per_page_ > 0) + { + Page_spacing_result ret = space_systems_with_fixed_number_per_page (configuration, first_page_num); + ret.demerits_ += (ret.force_.size () == n || ret.force_.size () == (n-1)) ? 0 : BAD_SPACING_PENALTY; + return ret; + } + cache_line_details (configuration); vsize min_p_count = min_page_count (configuration, first_page_num); bool valid_n = n >= min_p_count || n <= cached_line_details_.size (); @@ -770,11 +1242,11 @@ Page_breaking::space_systems_on_n_or_one_more_pages (vsize configuration, vsize m_res = finalize_spacing_result (configuration, m_res); n_res = finalize_spacing_result (configuration, n_res); - Real penalty = blank_page_penalty (); - n_res.demerits_ += penalty; + Real page_spacing_weight = robust_scm2double (book_->paper_->c_variable ("page-spacing-weight"), 10); + n_res.demerits_ += penalty_for_fewer_pages * page_spacing_weight; if (n_res.force_.size ()) - n_res.force_.back () += penalty; + n_res.force_.back () += penalty_for_fewer_pages; return (m_res.demerits_ < n_res.demerits_) ? m_res : n_res; } @@ -782,33 +1254,74 @@ Page_breaking::space_systems_on_n_or_one_more_pages (vsize configuration, vsize Page_spacing_result Page_breaking::space_systems_on_best_pages (vsize configuration, vsize first_page_num) { - vsize min_p_count = min_page_count (configuration, first_page_num); - Real odd_pages_penalty = blank_page_penalty (); + if (systems_per_page_ > 0) + return space_systems_with_fixed_number_per_page (configuration, first_page_num); cache_line_details (configuration); Page_spacer ps (cached_line_details_, first_page_num, this); - Page_spacing_result best = ps.solve (min_p_count); - best.force_.back () += (min_p_count % 2) ? odd_pages_penalty : 0; - best.demerits_ += (min_p_count % 2) ? odd_pages_penalty : 0; - for (vsize i = min_p_count+1; i <= cached_line_details_.size (); i++) + return finalize_spacing_result (configuration, ps.solve ()); +} + +Page_spacing_result +Page_breaking::space_systems_with_fixed_number_per_page (vsize configuration, + vsize first_page_num) +{ + Page_spacing_result res; + Page_spacing space (page_height (first_page_num, false), this); + vsize line = 0; + vsize page = 0; + vsize page_first_line = 0; + + cache_line_details (configuration); + while (line < cached_line_details_.size ()) { - Page_spacing_result cur = ps.solve (i); - cur.demerits_ += (i % 2) ? odd_pages_penalty : 0; - if (cur.demerits_ < best.demerits_) - best = cur; + page++; + space.clear (); + space.resize (page_height (first_page_num + page, false)); + + int system_count_on_this_page = 0; + while (system_count_on_this_page < systems_per_page_ + && line < cached_line_details_.size ()) + { + Line_details const &cur_line = cached_line_details_[line]; + space.append_system (cur_line); + system_count_on_this_page += cur_line.compressed_nontitle_lines_count_; + line++; + + if (cur_line.page_permission_ == ly_symbol2scm ("force")) + break; + } + + res.systems_per_page_.push_back (line - page_first_line); + + res.force_.push_back (space.force_); + res.penalty_ += cached_line_details_[line-1].page_penalty_; + if (system_count_on_this_page != systems_per_page_) + { + res.penalty_ += abs (system_count_on_this_page - systems_per_page_) * TERRIBLE_SPACING_PENALTY; + res.system_count_status_ |= ((system_count_on_this_page < systems_per_page_)) + ? SYSTEM_COUNT_TOO_FEW : SYSTEM_COUNT_TOO_MANY; + } + + page_first_line = line; } - return finalize_spacing_result (configuration, best); + /* Recalculate forces for the last page because we know now that is + really the last page. */ + space.resize (page_height (first_page_num + page, true)); + res.force_.back () = space.force_; + return finalize_spacing_result (configuration, res); } Page_spacing_result Page_breaking::pack_systems_on_least_pages (vsize configuration, vsize first_page_num) { + // TODO: add support for min/max-systems-per-page. Page_spacing_result res; vsize page = 0; vsize page_first_line = 0; - Page_spacing space (page_height (first_page_num, false), page_top_space_); + Page_spacing space (page_height (first_page_num, false), this); cache_line_details (configuration); for (vsize line = 0; line < cached_line_details_.size (); line++) @@ -874,7 +1387,7 @@ Page_breaking::finalize_spacing_result (vsize configuration, Page_spacing_result Real line_force = 0; Real line_penalty = 0; - Real page_force = 0; + Real page_demerits = res.penalty_; Real page_weighting = robust_scm2double (book_->paper_->c_variable ("page-spacing-weight"), 10); for (vsize i = 0; i < uncompressed_line_details_.size (); i++) @@ -886,10 +1399,8 @@ Page_breaking::finalize_spacing_result (vsize configuration, Page_spacing_result for (vsize i = 0; i < res.force_.size (); i++) { Real f = res.force_[i]; - if (isinf (f) && res.systems_per_page_[i] == 1) - f = 20000; - page_force += f * f; + page_demerits += min(f*f, BAD_SPACING_PENALTY); } /* for a while we tried averaging page and line forces across pages instead @@ -897,7 +1408,7 @@ Page_breaking::finalize_spacing_result (vsize configuration, Page_spacing_result with a very bad page force (for example because of a forced page break), the page breaker will put in a _lot_ of pages so that the bad force becomes averaged out over many pages. */ - res.demerits_ = line_force + line_penalty + (page_force + res.penalty_) * page_weighting; + res.demerits_ = line_force + line_penalty + page_demerits * page_weighting; return res; } @@ -912,15 +1423,20 @@ Page_breaking::finalize_spacing_result (vsize configuration, Page_spacing_result Page_spacing_result Page_breaking::space_systems_on_1_page (vector const &lines, Real page_height, bool ragged) { - Page_spacing space (page_height, page_top_space_); + Page_spacing space (page_height, this); Page_spacing_result ret; + int line_count = 0; for (vsize i = 0; i < lines.size (); i++) - space.append_system (lines[i]); + { + space.append_system (lines[i]); + line_count += lines[i].compressed_nontitle_lines_count_; + } ret.systems_per_page_.push_back (lines.size ()); ret.force_.push_back (ragged ? min (space.force_, 0.0) : space.force_); - ret.penalty_ = lines.back ().page_penalty_ + lines.back ().turn_penalty_; + ret.penalty_ = line_count_penalty (line_count) + lines.back ().page_penalty_ + lines.back ().turn_penalty_; + ret.system_count_status_ |= line_count_status (line_count); /* don't do finalize_spacing_result () because we are only an internal function */ return ret; @@ -947,29 +1463,54 @@ Page_breaking::space_systems_on_2_pages (vsize configuration, vsize first_page_n p1.systems_per_page_.push_back (p2.systems_per_page_[0]); p1.force_.push_back (p2.force_[0]); p1.penalty_ += p2.penalty_ - cached_line_details_[i].turn_penalty_; + p1.system_count_status_ |= p2.system_count_status_; return p1; } vector page1_force; vector page2_force; - Page_spacing page1 (page1_height, page_top_space_); - Page_spacing page2 (page2_height, page_top_space_); + + // page1_penalty and page2_penalty store the penalties based + // on min-systems-per-page and max-systems-per-page. + vector page1_penalty; + vector page2_penalty; + + // page1_status and page2_status keep track of whether the min-systems-per-page + // and max-systems-per-page constraints are satisfied. + vector page1_status; + vector page2_status; + + Page_spacing page1 (page1_height, this); + Page_spacing page2 (page2_height, this); + int page1_line_count = 0; + int page2_line_count = 0; page1_force.resize (cached_line_details_.size () - 1, infinity_f); page2_force.resize (cached_line_details_.size () - 1, infinity_f); + page1_penalty.resize (cached_line_details_.size () - 1, infinity_f); + page2_penalty.resize (cached_line_details_.size () - 1, infinity_f); + page1_status.resize (cached_line_details_.size () - 1, 0); + page2_status.resize (cached_line_details_.size () - 1, 0); /* find the page 1 and page 2 forces for each page-breaking position */ for (vsize i = 0; i < page1_force.size (); i++) { page1.append_system (cached_line_details_[i]); page2.prepend_system (cached_line_details_[cached_line_details_.size () - 1 - i]); + page1_line_count += cached_line_details_[i].compressed_nontitle_lines_count_; + page2_line_count += cached_line_details_[cached_line_details_.size () - 1 - i].compressed_nontitle_lines_count_; + page1_force[i] = (ragged1 && page1.force_ < 0 && i > 0) ? infinity_f : page1.force_; + page1_penalty[i] = line_count_penalty (page1_line_count); + page1_status[i] = line_count_status (page1_line_count); if (ragged2) page2_force[page2_force.size () - 1 - i] = (page2.force_ < 0 && i + 1 < page1_force.size ()) ? infinity_f : 0; else page2_force[page2_force.size () - 1 - i] = page2.force_; + page2_penalty[page2_penalty.size () - 1 - i] = line_count_penalty (page2_line_count); + page2_status[page2_penalty.size () - 1 - i] = line_count_status (page2_line_count); } /* find the position that minimises the sum of the page forces */ @@ -978,8 +1519,12 @@ Page_breaking::space_systems_on_2_pages (vsize configuration, vsize first_page_n for (vsize i = 0; i < page1_force.size (); i++) { Real f = page1_force[i] * page1_force[i] + page2_force[i] * page2_force[i]; - Real uneven = 2 * (page1_force[i] - page2_force[i]); - Real dem = uneven * uneven + f + + // NOTE: we treat max-systems-per-page and min-systems-per-page as soft + // constraints. That is, we penalize harshly when they don't happen + // but we don't completely reject. + Real dem = f + + page1_penalty[i] + page2_penalty[i] + cached_line_details_[i+1].page_penalty_ + cached_line_details_.back ().page_penalty_ + cached_line_details_.back ().turn_penalty_; if (dem < best_demerits) @@ -994,9 +1539,11 @@ Page_breaking::space_systems_on_2_pages (vsize configuration, vsize first_page_n ret.systems_per_page_.push_back (cached_line_details_.size () - best_sys_count); ret.force_.push_back (page1_force[best_sys_count-1]); ret.force_.push_back (page2_force[best_sys_count-1]); + ret.system_count_status_ = page1_status[best_sys_count-1] | page2_status[best_sys_count-1]; ret.penalty_ = cached_line_details_[best_sys_count-1].page_penalty_ + cached_line_details_.back ().page_penalty_ - + cached_line_details_.back ().turn_penalty_; + + cached_line_details_.back ().turn_penalty_ + + page1_penalty[best_sys_count-1] + page2_penalty[best_sys_count-1]; /* don't do finalize_spacing_result () because we are only an internal function */ return ret; @@ -1036,3 +1583,53 @@ Page_breaking::last_break_position () const { return breaks_.size () - 1; } + +// This gives the minimum distance between the top of the +// printable area (ie. the bottom of the top-margin) and +// the extent box of the topmost system. +Real +Page_breaking::min_whitespace_at_top_of_page (Line_details const &line) const +{ + SCM first_system_spacing = book_->paper_->c_variable ("top-system-spacing"); + if (line.title_) + first_system_spacing = book_->paper_->c_variable ("top-markup-spacing"); + + Real min_distance = -infinity_f; + Real padding = 0; + + Page_layout_problem::read_spacing_spec (first_system_spacing, + &min_distance, + ly_symbol2scm ("minimum-distance")); + Page_layout_problem::read_spacing_spec (first_system_spacing, + &padding, + ly_symbol2scm ("padding")); + + // FIXME: take into account the height of the header + Real translate = max (line.shape_.begin_[UP], line.shape_.rest_[UP]); + return max (0.0, max (padding, min_distance - translate)); +} + +Real +Page_breaking::min_whitespace_at_bottom_of_page (Line_details const &line) const +{ + SCM last_system_spacing = book_->paper_->c_variable ("last-bottom-spacing"); + Real min_distance = -infinity_f; + Real padding = 0; + + Page_layout_problem::read_spacing_spec (last_system_spacing, + &min_distance, + ly_symbol2scm ("minimum-distance")); + Page_layout_problem::read_spacing_spec (last_system_spacing, + &padding, + ly_symbol2scm ("padding")); + + // FIXME: take into account the height of the footer + Real translate = min (line.shape_.begin_[DOWN], line.shape_.rest_[DOWN]); + return max (0.0, max (padding, min_distance + translate)); +} + +int +Page_breaking::orphan_penalty () const +{ + return orphan_penalty_; +}