source file of the GNU LilyPond music typesetter
- (c) 2006 Joe Neeman <joeneeman@gmail.com>
+ (c) 2006--2007 Joe Neeman <joeneeman@gmail.com>
*/
#include "page-turn-page-breaking.hh"
{
}
-Real
-Page_turn_page_breaking::calc_demerits (const Break_node &me)
-{
- Real prev_f = 0;
- Real prev_dem = 0;
- Real page_weighting = robust_scm2double (book_->paper_->c_variable ("page-spacing-weight"), 1);
- if (me.prev_ != VPOS)
- {
- prev_f = state_[me.prev_].force_;
- prev_dem = state_[me.prev_].demerits_;
- }
-
- Real dem = me.force_ * me.force_ * page_weighting
- + me.line_force_ * me.line_force_
- + fabs (me.force_ - prev_f);
- if (isinf (me.line_force_) || isinf (me.force_))
- dem = infinity_f;
-
- return dem + prev_dem + me.penalty_ + me.line_penalty_;
-}
-
Page_turn_page_breaking::Break_node
Page_turn_page_breaking::put_systems_on_pages (vsize start,
vsize end,
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);
- Spacing_result result = space_systems_on_min_pages (lines, page_h, blank_force, ragged_all, ragged_last);
+ 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);
+ bool auto_first = to_boolean (book_->paper_->c_variable ("auto-first-page-number"));
+
+ /* If [START, END] does not contain an intermediate
+ breakpoint, we may need to consider solutions that result in a bad turn.
+ In this case, we won't abort if the min_page_count is too big */
+ if (start < end - 1 && min_p_count + (page_number % 2) > 2)
+ return Break_node ();
+
+ /* if PAGE-NUMBER is odd, we are starting on a right hand page. That is, we
+ have the options
+ PAGE-NUMBER odd:
+ - even number of pages + a blank page
+ - odd number of pages
+ PAGE-NUMBER even:
+ - odd number of pages + a blank page
+ - even number of pages
+
+ No matter which case PAGE-NUMBER falls into, we take the second choice if
+ min_p_count has that evenness. (For example, if PAGE-NUMBER is even and
+ min_p_count is even, we don't even consider the blank page option). */
+
+ Spacing_result result;
+ 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);
+ else
+ result = space_systems_on_n_pages (lines, min_p_count, page_h, ragged_all, ragged_last);
+ }
+ 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);
+ else
+ result = space_systems_on_n_or_one_more_pages (lines, min_p_count, page_h, blank_force, ragged_all, ragged_last);
Break_node ret;
ret.prev_ = start - 1;
ret.break_pos_ = end;
- ret.first_page_number_ = page_number;
ret.page_count_ = result.force_.size ();
- ret.force_ = 0;
- for (vsize i = 0; i < result.force_.size (); i++)
- ret.force_ += fabs (result.force_[i]);
+ ret.first_page_number_ = page_number;
+ if (auto_first && start == 0)
+ ret.first_page_number_ += 1 - (ret.page_count_ % 2);
- ret.penalty_ = result.penalty_;
ret.div_ = div;
ret.system_count_ = result.systems_per_page_;
ret.too_many_lines_ = true;
- ret.line_force_ = 0;
- ret.line_penalty_ = 0;
+ ret.demerits_ = result.penalty_;
+ if (start > 0)
+ ret.demerits_ += state_[start-1].demerits_;
for (vsize i = 0; i < lines.size (); i++)
{
- ret.line_force_ += fabs (lines[i].force_);
- ret.line_penalty_ += lines[i].break_penalty_;
+ 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;
}
+/* "final page" meaning the number of the final right-hand page,
+ which always has an odd page number */
+vsize
+Page_turn_page_breaking::final_page_num (Break_node const &b)
+{
+ vsize end = b.first_page_number_ + b.page_count_;
+ return end - 1 + (end % 2);
+}
+
void
Page_turn_page_breaking::calc_subproblem (vsize ending_breakpoint)
{
if (start > 0 && best.demerits_ < state_[start-1].demerits_)
continue;
- int p_num = 1;
+ int p_num = robust_scm2int (book_->paper_->c_variable ("first-page-number"), 1);
if (start > 0)
{
- /* if the last node has an odd number of pages and is not the first page,
- add a blank page */
- int p_count = state_[start-1].page_count_;
- int f_p_num = state_[start-1].first_page_number_;
- p_num = f_p_num + p_count + ((f_p_num > 1) ? p_count % 2 : 0);
+ /* except possibly for the first page, enforce the fact that first_page_number_
+ should always be even (left hand page).
+ TODO: are there different conventions in right-to-left languages?
+ */
+ p_num = state_[start-1].first_page_number_ + state_[start-1].page_count_;
+ p_num += p_num % 2;
}
Line_division min_division;
cur = put_systems_on_pages (start, end, line, div[d], p_num);
- if (cur.page_count_ > 2 &&
- (start < end - 1 || (!isinf (this_start_best.demerits_)
- && cur.page_count_ + cur.page_count_ % 2
- > this_start_best.page_count_ + this_start_best.page_count_ % 2)))
+ if (isinf (cur.demerits_)
+ || (cur.page_count_ + (p_num % 2) > 2
+ && (!isinf (this_start_best.demerits_))
+ && final_page_num (cur) > final_page_num (this_start_best)))
{
ok_page = false;
break;
}
- cur.demerits_ = calc_demerits (cur);
if (cur.demerits_ < this_start_best.demerits_)
{
break;
}
+ if (start == 0 && end == 1
+ && this_start_best.first_page_number_ == 1
+ && this_start_best.page_count_ > 1)
+ warning (_ ("cannot fit the first page turn onto a single page. "
+ "Consider setting first-page-number to an even number."));
+
if (this_start_best.demerits_ < best.demerits_)
best = this_start_best;
}
state_.clear ();
message (_f ("Calculating page and line breaks (%d possible page breaks)...",
(int)breaks_.size () - 1) + " ");
- for (vsize i = 0; i < breaks_.size () - 1; i++)
+ for (vsize i = 0; i + 1 < breaks_.size (); i++)
{
calc_subproblem (i);
progress_indication (string ("[") + to_string (i + 1) + "]");
for (vsize j = 0; j < soln[i].page_count_; j++)
lines_per_page.push_back (soln[i].system_count_[j]);
- if (i > 0 && i < soln.size () - 1 && soln[i].page_count_ % 2)
+ if (i + 1 < soln.size () && (soln[i].first_page_number_ + soln[i].page_count_) % 2)
/* add a blank page */
lines_per_page.push_back (0);
}
+
+ /* this should only actually modify first-page-number if
+ auto-first-page-number was true. */
+ book_->paper_->set_variable (ly_symbol2scm ("first-page-number"),
+ scm_from_int (soln[0].first_page_number_));
return Page_breaking::make_pages (lines_per_page, systems);
}
projects / lilypond.git / blobdiff