X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=lily%2Fpage-breaking.cc;h=4ac005461c68d66a5e187b8f58138c7a371423f0;hb=60d641c51caa5a53b185d40b6f6825417670887e;hp=fe59f55356a564382c284a87ad46163d507163ed;hpb=1189408d94b05d31e77a98ebc00a94aad13b4651;p=lilypond.git diff --git a/lily/page-breaking.cc b/lily/page-breaking.cc index fe59f55356..4ac005461c 100644 --- a/lily/page-breaking.cc +++ b/lily/page-breaking.cc @@ -1,10 +1,76 @@ /* - 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--2010 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. */ #include "page-breaking.hh" @@ -12,6 +78,7 @@ #include "international.hh" #include "item.hh" #include "output-def.hh" +#include "page-layout-problem.hh" #include "page-spacing.hh" #include "paper-book.hh" #include "paper-score.hh" @@ -32,8 +99,18 @@ 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_; + + compressed.shape_ = old.shape_.piggyback (orig[i].shape_, padding); + compressed.first_refpoint_offset_ += compressed.shape_.rest_[UP] - old.shape_.rest_[UP]; compressed.space_ += old.space_; compressed.inverse_hooke_ += old.inverse_hooke_; @@ -41,7 +118,9 @@ compress_lines (const vector &orig) compressed.compressed_nontitle_lines_count_ = old.compressed_nontitle_lines_count_ + (compressed.title_ ? 0 : 1); - compressed.title_ = compressed.title_ && old.title_; + // compressed.title_ is true if and only if the first of its + // compressed lines was a title. + compressed.title_ = old.title_; ret.back () = compressed; } else @@ -94,15 +173,30 @@ 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; 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); + + 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 () @@ -121,10 +215,22 @@ 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 max_systems_per_page_; +} + +int +Page_breaking::min_systems_per_page () const { - return page_top_space_; + return min_systems_per_page_; } vsize @@ -133,6 +239,40 @@ Page_breaking::system_count () const return system_count_; } +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, @@ -208,25 +348,53 @@ 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)); +} + +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 @@ -242,38 +410,86 @@ 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 +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 (); + } - SCM make_page = scm_c_module_lookup (layout_module, "stretch-and-draw-page"); + 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); + scm_apply_1 (page_stencil, page, SCM_EOL); + + return page; +} + +SCM +Page_breaking::make_pages (vector lines_per_page, SCM systems) +{ 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; @@ -286,16 +502,14 @@ 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; } book_->top_paper ()->set_variable (ly_symbol2scm ("label-page-table"), label_page_table); - ret = scm_reverse (ret); return ret; } @@ -315,14 +529,7 @@ 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 { @@ -336,7 +543,7 @@ Page_breaking::create_system_list () } 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"); @@ -347,25 +554,62 @@ 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); @@ -374,8 +618,8 @@ Page_breaking::find_chunks_and_breaks (Break_predicate is_break) } else { - /* 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)); @@ -441,7 +685,10 @@ Page_breaking::system_count_bounds (vector const &chunks, 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; @@ -524,7 +771,10 @@ 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 ()); @@ -550,10 +800,6 @@ 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 (); @@ -572,13 +818,11 @@ 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); + uncompressed_line_details_.push_back (Line_details (system_specs_[sys].prob_, book_->paper_)); } } cached_line_details_ = compress_lines (uncompressed_line_details_); + compute_line_heights (); } } @@ -629,37 +873,96 @@ 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; + Real prev_refpoint_hanging = 0; + for (vsize i = 0; i < cached_line_details_.size (); i++) + { + Line_shape shape = cached_line_details_[i].shape_; + Real a = shape.begin_[UP]; + Real b = shape.rest_[UP]; + bool title = cached_line_details_[i].title_; + Real refpoint_hanging = max (prev_hanging_begin + a, prev_hanging_rest + b); + + if (i > 0) + { + Real padding = 0; + if (!cached_line_details_[i].tight_spacing_) + padding = title + ? cached_line_details_[i-1].title_padding_ + : cached_line_details_[i-1].padding_; + Real min_dist = title + ? cached_line_details_[i-1].title_min_distance_ + : cached_line_details_[i-1].min_distance_; + refpoint_hanging = max (refpoint_hanging + padding, + prev_refpoint_hanging + min_dist + + cached_line_details_[i].first_refpoint_offset_); + } + + Real hanging_begin = refpoint_hanging - shape.begin_[DOWN]; + Real hanging_rest = refpoint_hanging - shape.rest_[DOWN]; + Real hanging = max (hanging_begin, hanging_rest); + cached_line_details_[i].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); + + if (cached_line_details_.size ()) + cur_page_height -= min_whitespace_at_top_of_page (cached_line_details_[0]); + 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); + Real ext_len; + if (cur_rod_height > 0) + ext_len = cached_line_details_[i].tallness_; + else + ext_len = cached_line_details_[i].full_height(); + Real next_rod_height = cur_rod_height + ext_len; + Real next_spring_height = cur_spring_height + cached_line_details_[i].space_; + Real next_height = next_rod_height + (ragged () ? next_spring_height : 0) + + min_whitespace_at_bottom_of_page (cached_line_details_[i]); + int next_line_count = line_count + cached_line_details_[i].compressed_nontitle_lines_count_; - if ((next_height > cur_page_height && cur_rod_height > 0) + if ((!too_few_lines (line_count) && (next_height > cur_page_height && cur_rod_height > 0)) + || too_many_lines (next_line_count) || (i > 0 && cached_line_details_[i-1].page_permission_ == ly_symbol2scm ("force"))) { - cur_rod_height = ext_len; + line_count = cached_line_details_[i].compressed_nontitle_lines_count_; + cur_rod_height = cached_line_details_[i].full_height(); cur_spring_height = cached_line_details_[i].space_; + page_starter = i; + cur_page_height = page_height (first_page_num + ret, false); + cur_page_height -= min_whitespace_at_top_of_page (cached_line_details_[i]); + ret++; } else { cur_rod_height = next_rod_height; cur_spring_height = next_spring_height; + line_count = next_line_count; } } @@ -677,29 +980,31 @@ Page_breaking::min_page_count (vsize configuration, vsize first_page_num) */ 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 (cur_height > cur_page_height + 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 ().extent_.length ()) + && cur_rod_height > cached_line_details_.back ().full_height ()) ret++; assert (ret <= cached_line_details_.size ()); return ret; } -// If systems_per_page is positive, we don't really try to space on N pages; +// 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, - int systems_per_page) +Page_breaking::space_systems_on_n_pages (vsize configuration, vsize n, vsize first_page_num) { Page_spacing_result ret; - if (systems_per_page > 0) + if (systems_per_page_ > 0) { - Page_spacing_result ret = space_systems_with_fixed_number_per_page (configuration, first_page_num, - systems_per_page); + 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; } @@ -745,19 +1050,18 @@ 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 +// 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, - int systems_per_page) + Real penalty_for_fewer_pages) { Page_spacing_result n_res; Page_spacing_result m_res; - if (systems_per_page > 0) + if (systems_per_page_ > 0) { - Page_spacing_result ret = space_systems_with_fixed_number_per_page (configuration, first_page_num, - systems_per_page); + 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; } @@ -792,11 +1096,11 @@ 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; } @@ -804,33 +1108,18 @@ 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 (); - 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++) - { - Page_spacing_result cur = ps.solve (i); - cur.demerits_ += (i % 2) ? odd_pages_penalty : 0; - if (cur.demerits_ < best.demerits_) - best = cur; - } - - return finalize_spacing_result (configuration, best); + 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, - int systems_per_page) + vsize first_page_num) { Page_spacing_result res; - Page_spacing space (page_height (first_page_num, false), page_top_space_); + Page_spacing space (page_height (first_page_num, false), this); vsize line = 0; vsize page = 0; vsize page_first_line = 0; @@ -843,7 +1132,7 @@ Page_breaking::space_systems_with_fixed_number_per_page (vsize configuration, 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 + while (system_count_on_this_page < systems_per_page_ && line < cached_line_details_.size ()) { Line_details const &cur_line = cached_line_details_[line]; @@ -856,13 +1145,21 @@ Page_breaking::space_systems_with_fixed_number_per_page (vsize configuration, } 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_ += 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; } /* Recalculate forces for the last page because we know now that is - was really the last page. */ + really the last page. */ space.resize (page_height (first_page_num + page, true)); res.force_.back () = space.force_; return finalize_spacing_result (configuration, res); @@ -871,10 +1168,11 @@ Page_breaking::space_systems_with_fixed_number_per_page (vsize configuration, 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++) @@ -940,7 +1238,7 @@ 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++) @@ -952,10 +1250,8 @@ 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 @@ -963,7 +1259,7 @@ 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; } @@ -978,15 +1274,20 @@ 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; @@ -1013,29 +1314,54 @@ 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 */ @@ -1044,8 +1370,12 @@ 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) @@ -1060,9 +1390,11 @@ 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; @@ -1102,3 +1434,53 @@ 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-title-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 ("bottom-system-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_; +}