page-breaking algorithms.
Conflicts:
lily/page-breaking.cc
Optimal_page_breaking (Paper_book *pb);
virtual ~Optimal_page_breaking ();
-
-private:
- Spacing_result try_page_spacing (Line_division const&);
};
#endif /* OPTIMAL_PAGE_BREAKING_HH */
#define PAGE_BREAKING_HH
#include "constrained-breaking.hh"
+#include "page-spacing.hh"
/* Either a paper-score, markup or header.
*/
Page_breaking (Paper_book *pb, Break_predicate);
virtual ~Page_breaking ();
+ bool ragged () const;
+ bool ragged_last () const;
+ bool last () const;
+ Real page_height (int page_number, bool last) const;
+
protected:
Paper_book *book_;
- Real page_height (int page_number, bool last);
vsize next_system (Break_position const &break_pos) const;
SCM make_pages (vector<vsize> lines_per_page, SCM lines);
vsize min_system_count (vsize start, vsize end);
vsize max_system_count (vsize start, vsize end);
- vector<Line_details> line_details (vsize start, vsize end, Line_division const &div);
+
void break_into_pieces (vsize start, vsize end, Line_division const &div);
SCM systems ();
-
- vector<Line_division> line_divisions (vsize start,
- vsize end,
- vsize system_count,
- Line_division lower_bound = Line_division (),
- Line_division upper_bound = Line_division ());
+ void set_current_breakpoints (vsize start,
+ vsize end,
+ vsize system_count,
+ Line_division lower_bound = Line_division (),
+ Line_division upper_bound = Line_division ());
+ vsize current_configuration_count () const;
+ Line_division current_configuration (vsize configuration_index) const;
+ Spacing_result space_systems_on_n_pages (vsize configuration_index, vsize n, vsize first_page_num);
+ Spacing_result space_systems_on_n_or_one_more_pages (vsize configuration_index, vsize n, vsize first_page_num);
+ Spacing_result space_systems_on_best_pages (vsize configuration_index, vsize first_page_num);
+ vsize min_page_count (vsize configuration_index, vsize first_page_num);
+ bool all_lines_stretched (vsize configuration_index);
+ Real blank_page_penalty () const;
SCM breakpoint_property (vsize breakpoint, char const *str);
vector<Break_position> breaks_;
vector<Break_position> chunks_;
vector<System_spec> all_;
vector<Constrained_breaking> line_breaking_;
+ bool ragged_;
+ bool ragged_last_;
+
+ vector<Line_division> current_configurations_;
+ vector<Break_position> current_chunks_;
+ vsize current_start_breakpoint_;
+ vsize current_end_breakpoint_;
+
+ void cache_line_details (vsize configuration_index);
+ void clear_line_details_cache ();
+ vsize cached_configuration_index_;
+ vector<Line_details> cached_line_details_;
vector<Break_position> chunk_list (vsize start, vsize end);
Line_division system_count_bounds (vector<Break_position> const &chunks, bool min);
void line_divisions_rec (vsize system_count,
Line_division const &min,
Line_division const &max,
- vector<Line_division> *result,
Line_division *cur);
+ vector<Line_details> line_details (vsize start, vsize end, Line_division const &div);
+ Spacing_result space_systems_on_1_page (vector<Line_details> const &lines, Real page_height, bool ragged);
+ Spacing_result space_systems_on_2_pages (vsize configuration_index, vsize first_page_num);
+ Spacing_result finalize_spacing_result (vsize configuration_index, Spacing_result);
void create_system_list ();
void find_chunks_and_breaks (Break_predicate);
};
calculations so they can be reused for querying different page counts.
*/
+class Page_breaking;
+
class Page_spacer
{
public:
- Page_spacer (vector<Line_details> const &lines, Real page_height, bool ragged, bool ragged_last);
+ Page_spacer (vector<Line_details> const &lines, vsize first_page_num, Page_breaking const*);
Spacing_result solve (vsize page_count);
private:
vsize prev_;
};
- Real page_height_;
+ Page_breaking const *breaker_;
+ vsize first_page_num_;
vector<Line_details> lines_;
Matrix<Page_spacing_node> state_;
vsize max_page_count_;
bool calc_subproblem (vsize page, vsize lines);
};
-vsize
-min_page_count (vector<Line_details> const &lines,
- Real page_height, bool ragged, bool ragged_last);
-
-Spacing_result
-space_systems_on_n_pages (vector<Line_details> const&,
- vsize n,
- Real page_height,
- bool ragged,
- bool ragged_last);
-
-Spacing_result
-space_systems_on_n_or_one_more_pages (vector<Line_details> const&,
- vsize n,
- Real page_height,
- Real odd_pages_penalty,
- bool ragged,
- bool ragged_last);
-Spacing_result
-space_systems_on_best_pages (vector<Line_details> const&,
- Real page_height,
- Real odd_pages_penalty,
- bool ragged,
- bool ragged_last);
+struct Page_spacing
+{
+ Real force_;
+ Real page_height_;
+ Real rod_height_;
+ Real spring_len_;
+ Real inverse_spring_k_;
+
+ Line_details last_line_;
+
+ Page_spacing (Real page_height)
+ {
+ page_height_ = page_height;
+ clear ();
+ }
+
+ void calc_force ();
+
+ void append_system (const Line_details &line);
+ void prepend_system (const Line_details &line);
+ void clear ();
+};
+Real line_space (Line_details const &line);
#endif /* PAGE_SPACING_HH */
vsize final_page_num (Break_node const &b);
Break_node put_systems_on_pages (vsize start,
vsize end,
- vector<Line_details> const &lines,
- Line_division const &div,
- int page_number);
+ vsize configuration,
+ vsize page_number);
SCM make_lines (vector<Break_node> *breaks);
SCM make_pages (vector<Break_node> const &breaks, SCM systems);
{
}
-Spacing_result
-Optimal_page_breaking::try_page_spacing (Line_division const &line_count)
-{
- vector<Line_details> lines = line_details (0, breaks_.size () - 1, line_count);
- Real page_h = page_height (1, false); // FIXME
- SCM force_sym = ly_symbol2scm ("blank-last-page-force");
- Real blank_force = robust_scm2double (book_->paper_->lookup_variable (force_sym), 0);
- bool ragged_all = to_boolean (book_->paper_->c_variable ("ragged-bottom"));
- bool ragged_last = to_boolean (book_->paper_->c_variable ("ragged-last-bottom"));
- Spacing_result ret = space_systems_on_best_pages (lines,
- page_h,
- blank_force,
- ragged_all,
- ragged_last);
-
- /* add in the line penalties */
- Real line_force = 0;
- Real line_penalty = 0;
- Real page_weighting = robust_scm2double (book_->paper_->c_variable ("page-spacing-weight"), 10);
-
- for (vsize i = 0; i < lines.size (); i++)
- {
- line_force += lines[i].force_ * lines[i].force_;
- line_penalty += lines[i].break_penalty_;
- }
-
- ret.demerits_ = ret.force_[0] * ret.force_[0] * page_weighting;
- for (vsize i = 1; i < ret.force_.size (); i++)
- ret.demerits_ += ret.force_[i] * ret.force_[i] * page_weighting;
-
- /* for a while we tried averaging page and line forces instead of summing
- them, but it caused the following problem. If there is a single page
- 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. */
- ret.demerits_ += line_force + line_penalty;
- return ret;
-}
-
SCM
Optimal_page_breaking::solve ()
{
Spacing_result best;
Line_division best_division;
Line_division lower_bound;
+ vsize first_page_num = robust_scm2int (book_->paper_->c_variable ("first-page-number"), 1);
for (vsize sys_count = min_sys_count;
cur_page_count <= max_page_count && sys_count <= max_sys_count;
sys_count++)
{
- Real this_best_demerits = infinity_f;
- vector<Line_division> div = line_divisions (0, end, sys_count, lower_bound);
- for (vsize d = 0; d < div.size (); d++)
+ Real best_demerits_for_this_sys_count = infinity_f;
+ set_current_breakpoints (0, end, sys_count, lower_bound);
+
+ for (vsize i = 0; i < current_configuration_count (); i++)
{
- Spacing_result cur = try_page_spacing (div[d]);
+ Spacing_result cur = space_systems_on_best_pages (i, first_page_num);
cur_page_count = cur.systems_per_page_.size ();
if (cur.demerits_ < best.demerits_ || isinf (best.demerits_))
{
best = cur;
- best_division = div[d];
+ best_division = current_configuration (i);
}
- if (cur.demerits_ < this_best_demerits || isinf (best.demerits_))
+ if (cur.demerits_ < best_demerits_for_this_sys_count || isinf (best.demerits_))
{
- this_best_demerits = cur.demerits_;
- lower_bound = div[d];
+ best_demerits_for_this_sys_count = cur.demerits_;
+ lower_bound = current_configuration (i);
}
- vector<Line_details> det = line_details (0, end, div[d]);
- bool all_lines_stretched = true;
- for (vsize i = 0; i < det.size (); i++)
- if (det[i].force_ < 0)
- all_lines_stretched = false;
-
- if (all_lines_stretched)
+ if (all_lines_stretched (i))
max_page_count = min (max_page_count, cur_page_count + 1);
}
}
#include "system.hh"
#include "warn.hh"
+/* for each forbidden page break, merge the systems around it into one system. */
+static vector<Line_details>
+compress_lines (const vector<Line_details> &orig)
+{
+ vector<Line_details> ret;
+
+ for (vsize i = 0; i < orig.size (); i++)
+ {
+ if (ret.size () && !scm_is_symbol (ret.back ().page_permission_))
+ {
+ 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_;
+ 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;
+ ret.back () = compressed;
+ }
+ else
+ {
+ ret.push_back (orig[i]);
+ ret.back ().force_ = 0;
+ }
+ }
+ return ret;
+}
+
+/* translate the number of systems-per-page into something meaningful for
+ the uncompressed lines.
+*/
+static vector<vsize>
+uncompress_solution (vector<vsize> const &systems_per_page,
+ vector<Line_details> const &compressed)
+{
+ vector<vsize> ret;
+ vsize start_sys = 0;
+
+ for (vsize i = 0; i < systems_per_page.size (); i++)
+ {
+ int compressed_count = 0;
+ for (vsize j = start_sys; j < start_sys + systems_per_page[i]; j++)
+ compressed_count += (int)compressed[j].force_;
+
+ ret.push_back (systems_per_page[i] + compressed_count);
+ start_sys += systems_per_page[i];
+ }
+ return ret;
+}
+
/* for Page_breaking, the start index (when we are dealing with the stuff
between a pair of breakpoints) refers to the break_ index of the end of
the previous page. So the system index of the start of the current page
Page_breaking::Page_breaking (Paper_book *pb, Break_predicate is_break)
{
book_ = pb;
+ ragged_ = to_boolean (pb->paper_->c_variable ("ragged"));
+ ragged_last_ = to_boolean (pb->paper_->c_variable ("ragged-last"));
create_system_list ();
find_chunks_and_breaks (is_break);
}
{
}
+bool
+Page_breaking::ragged () const
+{
+ return ragged_;
+}
+
+bool
+Page_breaking::ragged_last () const
+{
+ return ragged_last_;
+}
+
/* translate indices into breaks_ into start-end parameters for the line breaker */
void
Page_breaking::line_breaker_args (vsize sys,
return scm_append (scm_reverse (ret));
}
-vector<Line_details>
-Page_breaking::line_details (vsize start_break, vsize end_break, Line_division const &div)
-{
- vector<Break_position> chunks = chunk_list (start_break, end_break);
- vector<Line_details> ret;
- assert (chunks.size () == div.size () + 1);
-
- 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);
-
- for (vsize i = 0; i + 1 < chunks.size (); i++)
- {
- vsize sys = next_system (chunks[i]);
- if (all_[sys].pscore_)
- {
- vsize start;
- vsize end;
- line_breaker_args (sys, chunks[i], chunks[i+1], &start, &end);
-
- vector<Line_details> details = line_breaking_[sys].line_details (start, end, div[i]);
- ret.insert (ret.end (), details.begin (), details.end ());
- }
- else
- {
- assert (div[i] == 1);
- ret.push_back (Line_details (all_[sys].prob_));
- ret.back ().padding_ = padding;
- }
- }
- return ret;
-}
-
Real
-Page_breaking::page_height (int page_num, bool last)
+Page_breaking::page_height (int page_num, bool last) const
{
SCM mod = scm_c_resolve_module ("scm page");
SCM calc_height = scm_c_module_lookup (mod, "calc-printable-height");
return ret;
}
-vector<Page_breaking::Line_division>
-Page_breaking::line_divisions (vsize start,
- vsize end,
- vsize system_count,
- Line_division lower_bound,
- Line_division upper_bound)
+void
+Page_breaking::set_current_breakpoints (vsize start,
+ vsize end,
+ vsize system_count,
+ Line_division lower_bound,
+ Line_division upper_bound)
{
- vector<Break_position> chunks = chunk_list (start, end);
+ current_chunks_ = chunk_list (start, end);
+ current_start_breakpoint_ = start;
+ current_end_breakpoint_ = end;
+ clear_line_details_cache ();
if (!lower_bound.size ())
- lower_bound = system_count_bounds (chunks, true);
+ lower_bound = system_count_bounds (current_chunks_, true);
if (!upper_bound.size ())
- upper_bound = system_count_bounds (chunks, false);
+ upper_bound = system_count_bounds (current_chunks_, false);
- assert (lower_bound.size () == chunks.size () - 1);
- assert (upper_bound.size () == chunks.size () - 1);
+ assert (lower_bound.size () == current_chunks_.size () - 1);
+ assert (upper_bound.size () == current_chunks_.size () - 1);
- vector<Line_division> ret;
Line_division work_in_progress;
-
+ current_configurations_.clear ();
line_divisions_rec (system_count,
lower_bound,
upper_bound,
- &ret,
&work_in_progress);
- return ret;
+}
+
+vsize
+Page_breaking::current_configuration_count () const
+{
+ return current_configurations_.size ();
+}
+
+void
+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);
+
+ Line_division &div = current_configurations_[configuration_index];
+ cached_line_details_.clear ();
+ for (vsize i = 0; i + 1 < current_chunks_.size (); i++)
+ {
+ vsize sys = next_system (current_chunks_[i]);
+ if (all_[sys].pscore_)
+ {
+ vsize start;
+ vsize end;
+ line_breaker_args (sys, current_chunks_[i], current_chunks_[i+1], &start, &end);
+
+ vector<Line_details> details = line_breaking_[sys].line_details (start, end, div[i]);
+ cached_line_details_.insert (cached_line_details_.end (), details.begin (), details.end ());
+ }
+ else
+ {
+ assert (div[i] == 1);
+ cached_line_details_.push_back (Line_details (all_[sys].prob_));
+ cached_line_details_.back ().padding_ = padding;
+ }
+ }
+ cached_line_details_ = compress_lines (cached_line_details_);
+ }
+}
+
+void
+Page_breaking::clear_line_details_cache ()
+{
+ cached_configuration_index_ = VPOS;
+ cached_line_details_.clear ();
}
void
Page_breaking::line_divisions_rec (vsize system_count,
Line_division const &min_sys,
Line_division const &max_sys,
- vector<Line_division > *result,
Line_division *cur_division)
{
vsize my_index = cur_division->size ();
{
cur_division->push_back (i);
if (my_index == min_sys.size () - 1)
- result->push_back (*cur_division);
+ current_configurations_.push_back (*cur_division);
else
- line_divisions_rec (system_count - i, min_sys, max_sys, result, cur_division);
+ line_divisions_rec (system_count - i, min_sys, max_sys, cur_division);
cur_division->pop_back ();
}
}
+
+vsize
+Page_breaking::min_page_count (vsize configuration, vsize first_page_num)
+{
+ vsize ret = 1;
+ Real cur_rod_height = 0;
+ Real cur_spring_height = 0;
+ Real cur_page_height = page_height (first_page_num, false);
+
+ 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 + line_space (cached_line_details_[i]);
+ Real next_height = next_rod_height + (ragged () ? next_spring_height : 0);
+
+
+ if ((next_height > cur_page_height && cur_rod_height > 0)
+ || (i + 1 < cached_line_details_.size ()
+ && cached_line_details_[i].page_permission_ == ly_symbol2scm ("force")))
+ {
+ cur_rod_height = ext_len;
+ cur_spring_height = line_space (cached_line_details_[i]);
+ cur_page_height = page_height (first_page_num + ret, false);
+ ret++;
+ }
+ else
+ {
+ cur_rod_height = next_rod_height;
+ cur_spring_height = next_spring_height;
+ }
+ }
+
+ /* there are two potential problems with the last page (because we didn't know
+ it was the last page until after we managed to fit all the systems to it):
+ - we are ragged-last but the last page has a compressed spring
+ - the value returned by page_height (num, true) is smaller than the
+ value returned by page_height (num, false) and it causes the page not to
+ fit.
+
+ In either case, we just need to add one more page. This is because the last
+ line will always fit on the extra page and by adding one more page to the
+ end, the previous page is no longer the last page, so our previous
+ 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)
+ ret++;
+ return ret;
+}
+
+Spacing_result
+Page_breaking::space_systems_on_n_pages (vsize configuration, vsize n, vsize first_page_num)
+{
+ Spacing_result ret;
+ assert (n >= min_page_count (configuration, first_page_num));
+
+ cache_line_details (configuration);
+ if (n > cached_line_details_.size ())
+ return Spacing_result ();
+ if (n == 1)
+ ret = space_systems_on_1_page (cached_line_details_,
+ page_height (first_page_num, last ()),
+ ragged () || (last () && ragged_last ()));
+ else if (n == 2)
+ ret = space_systems_on_2_pages (configuration, first_page_num);
+ else
+ {
+ Page_spacer ps (cached_line_details_, first_page_num, this);
+ ret = ps.solve (n);
+ }
+
+ return finalize_spacing_result (configuration, ret);
+}
+
+Real
+Page_breaking::blank_page_penalty () const
+{
+ SCM penalty_sym = last () ? ly_symbol2scm ("blank-last-page-force") : ly_symbol2scm ("blank-page-force");
+ return robust_scm2double (book_->paper_->lookup_variable (penalty_sym), 0.0);
+}
+
+Spacing_result
+Page_breaking::space_systems_on_n_or_one_more_pages (vsize configuration, vsize n, vsize first_page_num)
+{
+ Spacing_result n_res = space_systems_on_n_pages (configuration, n, first_page_num);
+ Spacing_result m_res = space_systems_on_n_pages (configuration, n+1, first_page_num);
+ Real penalty = blank_page_penalty ();
+ n_res.demerits_ += penalty;
+ n_res.force_.back () += penalty;
+
+ if (n_res.demerits_ < m_res.demerits_)
+ return n_res;
+ return m_res;
+}
+
+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);
+ 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++)
+ {
+ 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);
+}
+
+/* Calculate demerits and fix res.systems_per_page_ so that
+ it refers to the original line numbers, not the ones given by compress_lines (). */
+Spacing_result
+Page_breaking::finalize_spacing_result (vsize configuration, Spacing_result res)
+{
+ cache_line_details (configuration);
+ res.systems_per_page_ = uncompress_solution (res.systems_per_page_, cached_line_details_);
+
+ Real line_force = 0;
+ Real line_penalty = 0;
+ Real page_force = 0;
+ Real page_weighting = robust_scm2double (book_->paper_->c_variable ("page-spacing-weight"), 10);
+
+ for (vsize i = 0; i < cached_line_details_.size (); i++)
+ {
+ line_force += cached_line_details_[i].force_ * cached_line_details_[i].force_;
+ line_penalty += cached_line_details_[i].break_penalty_;
+ }
+
+ for (vsize i = 0; i < res.force_.size (); i++)
+ page_force += res.force_[i] * res.force_[i];
+
+ /* for a while we tried averaging page and line forces across pages instead
+ of summing them, but it caused a problem: if there is a single page
+ 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;
+ return res;
+
+}
+
+/* the cases for page_count = 1 or 2 can be done in O (n) time. Since they
+ are by far the most common cases, we have special functions for them.
+
+ space_systems_on_1_page has a different calling convention than most of the
+ space_systems functions. This is because space_systems_on_1_page is (unlike
+ the other space_systems functions) sometimes called on subsets of a full
+ configuration. */
+Spacing_result
+Page_breaking::space_systems_on_1_page (vector<Line_details> const &lines, Real page_height, bool ragged)
+{
+ Page_spacing space (page_height);
+ Spacing_result ret;
+
+ for (vsize i = 0; i < lines.size (); i++)
+ space.append_system (lines[i]);
+
+ 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_;
+
+ /* don't do finalize_spacing_result () because we are only an internal function */
+ return ret;
+}
+
+Spacing_result
+Page_breaking::space_systems_on_2_pages (vsize configuration, vsize first_page_num)
+{
+ Real page1_height = page_height (first_page_num, false);
+ Real page2_height = page_height (first_page_num+1, last ());
+ bool ragged1 = ragged ();
+ bool ragged2 = ragged () || (last () && ragged_last ());
+
+ /* if there is a forced break, this reduces to 2 1-page problems */
+ cache_line_details (configuration);
+ for (vsize i = 0; i + 1 < cached_line_details_.size (); i++)
+ if (cached_line_details_[i].page_permission_ == ly_symbol2scm ("force"))
+ {
+ vector<Line_details> lines1 (cached_line_details_.begin (), cached_line_details_.begin () + i + 1);
+ vector<Line_details> lines2 (cached_line_details_.begin () + i + 1, cached_line_details_.end ());
+ Spacing_result p1 = space_systems_on_1_page (lines1, page1_height, ragged1);
+ Spacing_result p2 = space_systems_on_1_page (lines2, page2_height, ragged2);
+
+ 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_;
+ return p1;
+ }
+
+ vector<Real> page1_force;
+ vector<Real> page2_force;
+ Page_spacing page1 (page1_height);
+ Page_spacing page2 (page2_height);
+
+ page1_force.resize (cached_line_details_.size () - 1, infinity_f);
+ page2_force.resize (cached_line_details_.size () - 1, infinity_f);
+
+ /* 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_force[i] = (ragged1 && page1.force_ < 0 && i > 0) ? infinity_f : page1.force_;
+
+ 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_;
+ }
+
+ /* find the position that minimises the sum of the page forces */
+ vsize best_sys_count = 1;
+ Real best_demerits = infinity_f;
+ for (vsize i = 0; i < page1_force.size (); i++)
+ {
+ Real dem = page1_force[i] * page1_force[i]
+ + page2_force[i] * page2_force[i]
+ + cached_line_details_[i+1].page_penalty_
+ + cached_line_details_.back ().page_penalty_ + cached_line_details_.back ().turn_penalty_;
+ if (dem < best_demerits)
+ {
+ best_demerits = dem;
+ best_sys_count = i+1;
+ }
+ }
+
+ Spacing_result ret;
+ ret.systems_per_page_.push_back (best_sys_count);
+ 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.penalty_ = cached_line_details_[best_sys_count-1].page_penalty_
+ + cached_line_details_.back ().page_penalty_
+ + cached_line_details_.back ().turn_penalty_;
+
+ /* don't do finalize_spacing_result () because we are only an internal function */
+ return ret;
+}
+
+bool
+Page_breaking::all_lines_stretched (vsize configuration)
+{
+ cache_line_details (configuration);
+ for (vsize i = 0; i < cached_line_details_.size (); i++)
+ if (cached_line_details_[i].force_ < 0)
+ return false;
+
+ return true;
+}
+
+Page_breaking::Line_division
+Page_breaking::current_configuration (vsize configuration_index) const
+{
+ return current_configurations_[configuration_index];
+}
+
+bool Page_breaking::last () const
+{
+ return current_end_breakpoint_ == breaks_.size () - 1;
+}
#include "page-spacing.hh"
#include "matrix.hh"
+#include "page-breaking.hh"
#include "warn.hh"
-/*
- A much simplified rods-and-springs problem.
- */
-struct Page_spacing
-{
- Real force_;
- Real page_height_;
- Real rod_height_;
- Real spring_len_;
- Real inverse_spring_k_;
-
- Line_details last_line_;
-
- Page_spacing (Real page_height)
- {
- page_height_ = page_height;
- clear ();
- }
-
- void calc_force ();
-
- void append_system (const Line_details &line);
- void prepend_system (const Line_details &line);
- void clear ();
-};
-
/* In order to prevent possible division by zero, we require every line
to have a spring of non-zero length. */
-static Real
+Real
line_space (const Line_details &line)
{
return max (0.1, line.space_);
inverse_spring_k_ = 0;
}
-/* for each forbidden page break, merge the systems around it into one system. */
-static vector<Line_details>
-compress_lines (const vector<Line_details> &orig)
-{
- vector<Line_details> ret;
-
- for (vsize i = 0; i < orig.size (); i++)
- {
- if (ret.size () && !scm_is_symbol (ret.back ().page_permission_))
- {
- 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_;
- 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;
- ret.back () = compressed;
- }
- else
- {
- ret.push_back (orig[i]);
- ret.back ().force_ = 0;
- }
- }
- return ret;
-}
-
-/* translate the number of systems-per-page into something meaningful for
- the uncompressed lines.
-*/
-static vector<vsize>
-uncompress_solution (vector<vsize> const &systems_per_page,
- vector<Line_details> const &compressed)
-{
- vector<vsize> ret;
- vsize start_sys = 0;
-
- for (vsize i = 0; i < systems_per_page.size (); i++)
- {
- int compressed_count = 0;
- for (vsize j = start_sys; j < start_sys + systems_per_page[i]; j++)
- compressed_count += (int)compressed[j].force_;
-
- ret.push_back (systems_per_page[i] + compressed_count);
- start_sys += systems_per_page[i];
- }
- return ret;
-}
-
-/* the cases for page_count = 1 or 2 can be done in O (n) time. Since they
- are by far the most common cases, we have special functions for them */
-static Spacing_result
-space_systems_on_1_page (vector<Line_details> const &lines, Real page_height, bool ragged)
-{
- Page_spacing space (page_height);
- Spacing_result ret;
-
- for (vsize i = 0; i < lines.size (); i++)
- space.append_system (lines[i]);
-
- 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.demerits_ = ret.force_.back () * ret.force_.back () + ret.penalty_;
- return ret;
-}
-
-static Spacing_result
-space_systems_on_2_pages (vector<Line_details> const &lines,
- Real page_height,
- bool ragged,
- bool ragged_last)
-{
- /* if there is a forced break, this reduces to 2 1-page problems */
- for (vsize i = 0; i + 1 < lines.size (); i++)
- if (lines[i].page_permission_ == ly_symbol2scm ("force"))
- {
- vector<Line_details> lines1 (lines.begin (), lines.begin () + i + 1);
- vector<Line_details> lines2 (lines.begin () + i + 1, lines.end ());
- Spacing_result p1 = space_systems_on_1_page (lines1, page_height, ragged);
- Spacing_result p2 = space_systems_on_1_page (lines2, page_height, ragged || ragged_last);
-
- p1.systems_per_page_.push_back (p2.systems_per_page_[0]);
- p1.force_.push_back (p2.force_[0]);
- p1.penalty_ += p2.penalty_ - lines[i].turn_penalty_;
- p1.demerits_ += p2.demerits_ - lines[i].turn_penalty_;
- return p1;
- }
-
- vector<Real> page1_force;
- vector<Real> page2_force;
- Page_spacing page1 (page_height);
- Page_spacing page2 (page_height);
-
- page1_force.resize (lines.size () - 1, infinity_f);
- page2_force.resize (lines.size () - 1, infinity_f);
-
- for (vsize i = 0; i < page1_force.size (); i++)
- {
- page1.append_system (lines[i]);
- page2.prepend_system (lines[lines.size () - 1 - i]);
- page1_force[i] = (ragged && page1.force_ < 0 && i > 0) ? infinity_f : page1.force_;
-
- if (ragged || ragged_last)
- 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_;
- }
-
- vsize best_sys_count = 1;
- Real best_demerits = infinity_f;
- for (vsize i = 0; i < page1_force.size (); i++)
- {
- Real dem = page1_force[i] * page1_force[i]
- + page2_force[i] * page2_force[i]
- + lines[i+1].page_penalty_
- + lines.back ().page_penalty_ + lines.back ().turn_penalty_;
- if (dem < best_demerits)
- {
- best_demerits = dem;
- best_sys_count = i+1;
- }
- }
-
- Spacing_result ret;
- ret.systems_per_page_.push_back (best_sys_count);
- ret.systems_per_page_.push_back (lines.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.penalty_ = lines[best_sys_count-1].page_penalty_
- + lines.back ().page_penalty_
- + lines.back ().turn_penalty_;
- ret.demerits_ = best_demerits;
-
- return ret;
-}
-
-Page_spacer::Page_spacer (vector<Line_details> const &lines, Real page_height, bool ragged, bool ragged_last)
+Page_spacer::Page_spacer (vector<Line_details> const &lines, vsize first_page_num, Page_breaking const *breaker)
: lines_ (lines)
{
- page_height_ = page_height;
+ first_page_num_ = first_page_num;
+ breaker_ = breaker;
max_page_count_ = 0;
- ragged_ = ragged;
- ragged_last_ = ragged_last;
+ ragged_ = breaker->ragged ();
+ ragged_last_ = breaker->last () && breaker->ragged_last ();
}
Spacing_result
bool
Page_spacer::calc_subproblem (vsize page, vsize line)
{
- Page_spacing space (page_height_);
+ bool last = line == lines_.size () - 1;
+ Page_spacing space (breaker_->page_height (page + first_page_num_, last));
Page_spacing_node &cur = state_.at (line, page);
- bool ragged = ragged_ || (ragged_last_ && line == lines_.size () - 1);
+ bool ragged = ragged_ || (ragged_last_ && last);
for (vsize page_start = line+1; page_start > page && page_start--;)
{
return !isinf (cur.demerits_);
}
-vsize
-min_page_count (vector<Line_details> const &uncompressed_lines,
- Real page_height, bool ragged, bool ragged_last)
-{
- vsize ret = 1;
- Real cur_rod_height = 0;
- vector<Line_details> lines = compress_lines (uncompressed_lines);
-
- assert (lines.size ());
- for (vsize i = lines.size (); i--;)
- {
- bool rag = ragged || (ragged_last && ret == 1);
- Real ext_len = lines[i].extent_.length ();
- Real next_height = cur_rod_height + ext_len
- + (rag ? line_space (lines[i]) : 0)
- + ((cur_rod_height > 0) ? lines[i].padding_: 0);
-
- if ((next_height > page_height && cur_rod_height > 0)
- || (i + 1 < lines.size () && lines[i].page_permission_ == ly_symbol2scm ("force")))
- {
- ret++;
- cur_rod_height = ext_len + (rag ? line_space (lines[i]) : 0);
- }
- else
- cur_rod_height = next_height;
- }
-
- return ret;
-}
-
-Spacing_result
-space_systems_on_n_pages (vector<Line_details> const &lines,
- vsize n,
- Real page_height,
- bool ragged,
- bool ragged_last)
-{
- vector<Line_details> compressed_lines = compress_lines (lines);
- Spacing_result ret;
- assert (n >= min_page_count (lines, page_height, ragged, ragged_last));
-
- if (n > compressed_lines.size ())
- return Spacing_result ();
- if (n == 1)
- ret = space_systems_on_1_page (compressed_lines, page_height, ragged || ragged_last);
- else if (n == 2)
- ret = space_systems_on_2_pages (compressed_lines, page_height, ragged, ragged_last);
-
- Page_spacer ps (compressed_lines, page_height, ragged, ragged_last);
- ret = ps.solve (n);
-
- ret.systems_per_page_ = uncompress_solution (ret.systems_per_page_, compressed_lines);
- return ret;
-}
-
-Spacing_result
-space_systems_on_n_or_one_more_pages (vector<Line_details> const &lines,
- vsize n,
- Real page_height,
- Real odd_pages_penalty,
- bool ragged,
- bool ragged_last)
-{
- Spacing_result n_res = space_systems_on_n_pages (lines, n, page_height, ragged, ragged_last);
- Spacing_result m_res = space_systems_on_n_pages (lines, n+1, page_height, ragged, ragged_last);
- n_res.demerits_ += odd_pages_penalty;
- n_res.force_.back () += odd_pages_penalty;
-
- if (n_res.demerits_ < m_res.demerits_)
- return n_res;
- return m_res;
-}
-
-Spacing_result
-space_systems_on_best_pages (vector<Line_details> const &lines,
- Real page_height,
- Real odd_pages_penalty,
- bool ragged,
- bool ragged_last)
-{
- vector<Line_details> compressed_lines = compress_lines (lines);
- vsize min_p_count = min_page_count (compressed_lines, page_height, ragged, ragged_last);
-
- Page_spacer ps (compressed_lines, page_height, ragged, ragged_last);
- 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 <= compressed_lines.size (); i++)
- {
- Spacing_result cur = ps.solve (i);
- cur.demerits_ += (i % 2) ? odd_pages_penalty : 0;
- if (cur.demerits_ < best.demerits_)
- best = cur;
- }
-
- best.systems_per_page_ = uncompress_solution (best.systems_per_page_, compressed_lines);
- return best;
-}
Page_turn_page_breaking::Break_node
Page_turn_page_breaking::put_systems_on_pages (vsize start,
vsize end,
- vector<Line_details> const &lines,
- Line_division const &div,
- int page_number)
+ vsize configuration,
+ vsize page_number)
{
- bool last = end == breaks_.size () - 1;
- bool ragged_all = to_boolean (book_->paper_->c_variable ("ragged-bottom"));
- bool ragged_last = last && to_boolean (book_->paper_->c_variable ("ragged-last-bottom"));
- Real page_h = page_height (1, false); // FIXME
- SCM force_sym = last ? ly_symbol2scm ("blank-last-page-force") : ly_symbol2scm ("blank-page-force");
- Real blank_force = robust_scm2double (book_->paper_->lookup_variable (force_sym), 0);
- Real page_weighting = robust_scm2double (book_->paper_->c_variable ("page-spacing-weight"), 10);
- int min_p_count = min_page_count (lines, page_h, ragged_all, ragged_last);
+ vsize min_p_count = min_page_count (configuration, page_number);
bool auto_first = to_boolean (book_->paper_->c_variable ("auto-first-page-number"));
/* If [START, END] does not contain an intermediate
if (start == 0 && auto_first)
{
if (min_p_count % 2)
- result = space_systems_on_n_or_one_more_pages (lines, min_p_count, page_h, 0, ragged_all, ragged_last);
+ result = space_systems_on_n_or_one_more_pages (configuration, min_p_count, page_number);
else
- result = space_systems_on_n_pages (lines, min_p_count, page_h, ragged_all, ragged_last);
+ result = space_systems_on_n_pages (configuration, min_p_count, page_number);
}
else if (page_number % 2 == min_p_count % 2)
- result = space_systems_on_n_pages (lines, min_p_count, page_h, ragged_all, ragged_last);
+ result = space_systems_on_n_pages (configuration, min_p_count, page_number);
else
- result = space_systems_on_n_or_one_more_pages (lines, min_p_count, page_h, blank_force, ragged_all, ragged_last);
+ result = space_systems_on_n_or_one_more_pages (configuration, min_p_count, page_number);
Break_node ret;
ret.prev_ = start - 1;
if (auto_first && start == 0)
ret.first_page_number_ += 1 - (ret.page_count_ % 2);
- ret.div_ = div;
+ ret.div_ = current_configuration (configuration);
ret.system_count_ = result.systems_per_page_;
- ret.too_many_lines_ = true;
- ret.demerits_ = result.penalty_;
+ ret.too_many_lines_ = all_lines_stretched (configuration);
+ ret.demerits_ = result.demerits_;
if (start > 0)
ret.demerits_ += state_[start-1].demerits_;
- for (vsize i = 0; i < lines.size (); i++)
- {
- ret.demerits_ += lines[i].force_ * lines[i].force_;
- ret.demerits_ += lines[i].break_penalty_;
- if (lines[i].force_ < 0)
- ret.too_many_lines_ = false;
- }
- for (vsize i = 0; i < result.force_.size (); i++)
- ret.demerits_ += result.force_[i] * result.force_[i] * page_weighting;
+
return ret;
}
min_sys_count = max (min_sys_count, prev_best_system_count);
for (vsize sys_count = min_sys_count; sys_count <= max_sys_count && ok_page; sys_count++)
{
- vector<Line_division> div = line_divisions (start, end, sys_count, min_division, max_division);
+ set_current_breakpoints (start, end, sys_count, min_division, max_division);
bool found = false;
- for (vsize d = 0; d < div.size (); d++)
+ for (vsize i = 0; i < current_configuration_count (); i++)
{
- vector<Line_details> line = line_details (start, end, div[d]);
-
- cur = put_systems_on_pages (start, end, line, div[d], p_num);
+ cur = put_systems_on_pages (start, end, i, p_num);
if (isinf (cur.demerits_)
|| (cur.page_count_ + (p_num % 2) > 2
/* heuristic: if we increase the number of systems, we can bound the
division from below by our current best division */
- min_division = div[d];
+ min_division = current_configuration (i);
}
}
if (!found && this_start_best.too_many_lines_)