X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=lily%2Fpage-breaking.cc;h=038b0af2479b3f4db7a5a29488a493a9cc136f38;hb=598e295b35375e23040e61b60c68e75b0b00a7ad;hp=709ee52cb3eb433a9d9ead01143f12e49a07d9f2;hpb=02dfebc14562bc49b61bbf525c0a845d247a885f;p=lilypond.git diff --git a/lily/page-breaking.cc b/lily/page-breaking.cc index 709ee52cb3..038b0af247 100644 --- a/lily/page-breaking.cc +++ b/lily/page-breaking.cc @@ -4,7 +4,63 @@ source file of the GNU LilyPond music typesetter - (c) 2006--2007 Joe Neeman + (c) 2006--2009 Joe Neeman +*/ + +/* + 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 +68,7 @@ #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" @@ -37,11 +94,13 @@ compress_lines (const vector &orig) compressed.space_ += old.space_; compressed.inverse_hooke_ += old.inverse_hooke_; - /* 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_; ret.back () = compressed; } else @@ -67,7 +126,7 @@ 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]; @@ -97,8 +156,24 @@ Page_breaking::next_system (Break_position const &break_pos) const Page_breaking::Page_breaking (Paper_book *pb, Break_predicate is_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")); + 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)); + + 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); } @@ -119,6 +194,64 @@ Page_breaking::ragged_last () const return ragged_last_; } +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 min_systems_per_page_; +} + +vsize +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, @@ -194,23 +327,33 @@ Page_breaking::systems () return scm_append (scm_reverse (ret)); } +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 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 { 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"); - 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"), scm_from_bool (last), - SCM_UNDEFINED)); SCM height = scm_apply_1 (calc_height, page, SCM_EOL); - return scm_to_double (height) - scm_to_double (book_->paper_->c_variable ("page-top-space")); + return scm_to_double (height); } SCM @@ -226,35 +369,86 @@ 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 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); + 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); SCM ret = SCM_EOL; - SCM label_page_table = 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); - SCM last = scm_from_bool (i == lines_per_page.size () - 1); - SCM rag = scm_from_bool (ragged () || (to_boolean (last) - && 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, last, 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; @@ -267,16 +461,14 @@ 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_->paper_->set_variable (ly_symbol2scm ("label-page-table"), label_page_table); - ret = scm_reverse (ret); + book_->top_paper ()->set_variable (ly_symbol2scm ("label-page-table"), label_page_table); return ret; } @@ -296,14 +488,7 @@ 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 { @@ -328,8 +513,25 @@ 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; + + 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)); + + cols.push_back (system_specs_[i].pscore_->root_system ()->used_columns ()[0]); + for (vsize j = 0; j < details.size (); j++) + cols.push_back (details[j].last_column_); + } + else + cols = system_specs_[i].pscore_->root_system ()->used_columns (); + + int last_chunk_idx = 0; vector line_breaker_columns; line_breaker_columns.push_back (0); @@ -343,10 +545,22 @@ Page_breaking::find_chunks_and_breaks (Break_predicate is_break) 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_ = j - last_chunk_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_chunk_idx = j; + } if ((break_point || chunk_end) && !last) line_breaker_columns.push_back (j); @@ -422,7 +636,10 @@ 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; @@ -443,6 +660,7 @@ Page_breaking::set_current_breakpoints (vsize start, Line_division lower_bound, Line_division upper_bound) { + system_count_ = system_count; current_chunks_ = chunk_list (start, end); current_start_breakpoint_ = start; current_end_breakpoint_ = end; @@ -498,18 +716,24 @@ Page_breaking::set_to_ideal_line_configuration (vsize start, vsize end) current_start_breakpoint_ = start; current_end_breakpoint_ = end; clear_line_details_cache (); + system_count_ = 0; Line_division div; 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); + + system_count_ += div.back (); } current_configurations_.clear (); current_configurations_.push_back (div); @@ -526,10 +750,12 @@ Page_breaking::cache_line_details (vsize configuration_index) { if (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); + cached_configuration_index_ = configuration_index; + Real padding = 0; + SCM spacing_spec = book_->paper_->c_variable ("between-system-spacing"); + SCM page_breaking_spacing_spec = book_->paper_->c_variable ("page-breaking-between-system-spacing"); + Page_layout_problem::read_spacing_spec (spacing_spec, &padding, ly_symbol2scm ("padding")); + Page_layout_problem::read_spacing_spec (page_breaking_spacing_spec, &padding, ly_symbol2scm ("padding")); Line_division &div = current_configurations_[configuration_index]; uncompressed_line_details_.clear (); @@ -549,7 +775,9 @@ Page_breaking::cache_line_details (vsize configuration_index) { assert (div[i] == 1); uncompressed_line_details_.push_back (Line_details (system_specs_[sys].prob_)); - uncompressed_line_details_.back ().padding_ = padding; + uncompressed_line_details_.back ().padding_ = + robust_scm2double (system_specs_[sys].prob_->get_property ("next-padding"), + padding); } } cached_line_details_ = compress_lines (uncompressed_line_details_); @@ -607,33 +835,47 @@ 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 + line_space (cached_line_details_[i]); - Real next_height = next_rod_height + (ragged () ? next_spring_height : 0); + 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"))) { + line_count = cached_line_details_[i].compressed_nontitle_lines_count_; cur_rod_height = ext_len; - cur_spring_height = line_space (cached_line_details_[i]); + 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; } } @@ -651,8 +893,12 @@ 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 ()) ret++; @@ -661,20 +907,33 @@ Page_breaking::min_page_count (vsize configuration, vsize first_page_num) 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; - assert (n >= min_page_count (configuration, first_page_num)); + + 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); - if (n > cached_line_details_.size ()) - return Page_spacing_result (); - if (n == 1) + bool valid_n = (n >= min_page_count (configuration, first_page_num) + && n <= cached_line_details_.size ()); + + if (!valid_n) + programming_error ("number of pages is out of bounds"); + + if (n == 1 && valid_n) ret = space_systems_on_1_page (cached_line_details_, page_height (first_page_num, is_last ()), ragged () || (is_last () && ragged_last ())); - else if (n == 2) + else if (n == 2 && valid_n) ret = space_systems_on_2_pages (configuration, first_page_num); else { @@ -688,20 +947,45 @@ Page_breaking::space_systems_on_n_pages (vsize configuration, vsize n, vsize fir Real Page_breaking::blank_page_penalty () const { - SCM penalty_sym = is_last () ? ly_symbol2scm ("blank-last-page-force") : ly_symbol2scm ("blank-page-force"); + SCM penalty_sym; + + if (is_last ()) + penalty_sym = ly_symbol2scm ("blank-last-page-force"); + else if (ends_score ()) + penalty_sym = ly_symbol2scm ("blank-after-score-page-force"); + else + penalty_sym = ly_symbol2scm ("blank-page-force"); + + Break_position const &pos = breaks_[current_end_breakpoint_]; + if (Paper_score *ps = system_specs_[pos.system_spec_index_].pscore_) + return robust_scm2double (ps->layout ()->lookup_variable (penalty_sym), 0.0); + 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_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 (); + + if (!valid_n) + programming_error ("both page counts are out of bounds"); - if (n == 1) + if (n == 1 && valid_n) { bool rag = ragged () || (is_last () && ragged_last ()); Real height = page_height (first_page_num, is_last ()); @@ -715,9 +999,9 @@ Page_breaking::space_systems_on_n_or_one_more_pages (vsize configuration, vsize { Page_spacer ps (cached_line_details_, first_page_num, this); - if (n >= min_p_count) + if (n >= min_p_count || !valid_n) n_res = ps.solve (n); - if (n < cached_line_details_.size ()) + if (n < cached_line_details_.size () || !valid_n) m_res = ps.solve (n+1); } @@ -756,6 +1040,117 @@ Page_breaking::space_systems_on_best_pages (vsize configuration, vsize first_pag return finalize_spacing_result (configuration, best); } +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++; + 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_ += 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 + 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), this); + + cache_line_details (configuration); + for (vsize line = 0; line < cached_line_details_.size (); line++) + { + Real prev_force = space.force_; + space.append_system (cached_line_details_[line]); + if ((line > page_first_line) + && (isinf (space.force_) + || ((line > 0) + && (cached_line_details_[line-1].page_permission_ == ly_symbol2scm ("force"))))) + { + res.systems_per_page_.push_back (line - page_first_line); + res.force_.push_back (prev_force); + res.penalty_ += cached_line_details_[line-1].page_penalty_; + page++; + space.resize (page_height (first_page_num + page, false)); + space.clear (); + space.append_system (cached_line_details_[line]); + page_first_line = line; + } + + if (line == cached_line_details_.size () - 1) + { + /* This is the last line */ + /* When the last page height was computed, we did not know yet that it + * was the last one. If the systems put on it don't fit anymore, the last + * system is moved to a new page */ + space.resize (page_height (first_page_num + page, true)); + if ((line > page_first_line) && (isinf (space.force_))) + { + res.systems_per_page_.push_back (line - page_first_line); + res.force_.push_back (prev_force); + /* the last page containing the last line */ + space.resize (page_height (first_page_num + page + 1, true)); + space.clear (); + space.append_system (cached_line_details_[line]); + res.systems_per_page_.push_back (1); + res.force_.push_back (space.force_); + res.penalty_ += cached_line_details_[line-1].page_penalty_; + res.penalty_ += cached_line_details_[line].page_penalty_; + } + else + { + res.systems_per_page_.push_back (line + 1 - page_first_line); + res.force_.push_back (space.force_); + res.penalty_ += cached_line_details_[line].page_penalty_; + } + } + } + return finalize_spacing_result (configuration, res); +} + /* Calculate demerits and fix res.systems_per_page_ so that it refers to the original line numbers, not the ones given by compress_lines (). */ Page_spacing_result @@ -769,7 +1164,7 @@ 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++) @@ -781,10 +1176,8 @@ 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 @@ -792,7 +1185,7 @@ 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; } @@ -807,15 +1200,20 @@ 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_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; @@ -847,24 +1245,48 @@ Page_breaking::space_systems_on_2_pages (vsize configuration, vsize first_page_n vector page1_force; vector page2_force; - Page_spacing page1 (page1_height); - Page_spacing page2 (page2_height); + + // 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 */ @@ -873,8 +1295,12 @@ 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) @@ -889,9 +1315,11 @@ 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; @@ -920,8 +1348,56 @@ Page_breaking::is_last () const return current_end_breakpoint_ == last_break_position (); } +bool +Page_breaking::ends_score () const +{ + return breaks_[current_end_breakpoint_].score_ender_; +} + vsize 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 + return max (0.0, max (padding, min_distance - line.extent_[UP])); +} + +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 + return max (0.0, max (padding, min_distance + line.extent_[DOWN])); +}