2 This file is part of LilyPond, the GNU music typesetter.
4 Copyright (C) 2009--2011 Joe Neeman <joeneeman@gmail.com>
6 LilyPond is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or
9 (at your option) any later version.
11 LilyPond is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with LilyPond. If not, see <http://www.gnu.org/licenses/>.
20 #include "page-layout-problem.hh"
22 #include "align-interface.hh"
23 #include "axis-group-interface.hh"
24 #include "hara-kiri-group-spanner.hh"
25 #include "international.hh"
27 #include "output-def.hh"
28 #include "paper-book.hh"
29 #include "paper-column.hh"
30 #include "paper-score.hh"
31 #include "pointer-group-interface.hh"
33 #include "skyline-pair.hh"
35 #include "text-interface.hh"
38 Returns a stencil for the footnote of each system. This stencil may
39 itself be comprised of several footnotes.
43 Page_layout_problem::get_footnotes_from_lines (SCM lines, Real padding)
45 SCM footnotes = SCM_EOL;
46 // ugh...code dup from the Page_layout_problem constructor
47 for (SCM s = lines; scm_is_pair (s); s = scm_cdr (s))
49 if (Grob *g = unsmob_grob (scm_car (s)))
51 System *sys = dynamic_cast<System *> (g);
54 programming_error ("got a grob for footnotes that wasn't a System");
57 footnotes = scm_cons (sys->make_footnote_stencil (padding).smobbed_copy (), footnotes);
59 else if (Prob *p = unsmob_prob (scm_car (s)))
61 SCM stencils = p->get_property ("footnotes");
62 if (stencils == SCM_EOL)
64 Stencil footnote_stencil;
66 for (SCM st = stencils; scm_is_pair (st); st = scm_cdr (st))
67 footnote_stencil.add_at_edge (Y_AXIS, DOWN, *unsmob_stencil (scm_car (st)), padding);
68 footnotes = scm_cons (footnote_stencil.smobbed_copy (), footnotes);
72 if (!scm_is_pair (footnotes))
75 return scm_reverse (footnotes);
79 Page_layout_problem::get_footnote_separator_stencil (Output_def *paper)
81 SCM props = scm_call_1 (ly_lily_module_constant ("layout-extract-page-properties"),
84 SCM markup = paper->c_variable ("footnote-separator-markup");
86 if (!Text_interface::is_markup (markup))
89 SCM footnote_stencil = Text_interface::interpret_markup (paper->self_scm (),
92 Stencil *footnote_separator = unsmob_stencil (footnote_stencil);
94 return footnote_separator;
98 Page_layout_problem::add_footnotes_to_footer (SCM footnotes, Stencil *foot, Paper_book *pb)
100 bool footnotes_found = false;
101 Real footnote_padding = robust_scm2double (pb->paper_->c_variable ("footnote-padding"), 0.0);
102 Real footnote_footer_padding = robust_scm2double (pb->paper_->c_variable ("footnote-footer-padding"), 0.0);
104 footnotes = scm_reverse (footnotes);
106 for (SCM s = footnotes; scm_is_pair (s); s = scm_cdr (s))
108 Stencil *stencil = unsmob_stencil (scm_car (s));
113 if (!stencil->is_empty ())
115 foot->add_at_edge (Y_AXIS, UP, *stencil, (!footnotes_found ? footnote_footer_padding : footnote_padding));
116 footnotes_found = true;
122 Stencil *separator = get_footnote_separator_stencil (pb->paper_);
124 foot->add_at_edge (Y_AXIS, UP, *separator, footnote_padding);
128 Page_layout_problem::Page_layout_problem (Paper_book *pb, SCM page_scm, SCM systems)
129 : bottom_skyline_ (DOWN)
131 Prob *page = unsmob_prob (page_scm);
140 Stencil *head = unsmob_stencil (page->get_property ("head-stencil"));
141 Stencil *foot = unsmob_stencil (page->get_property ("foot-stencil"));
143 Real footnote_padding = 0.0;
144 if (pb && pb->paper_)
145 footnote_padding = robust_scm2double (pb->paper_->c_variable ("footnote-padding"), 0.0);
146 SCM footnotes = get_footnotes_from_lines (systems, footnote_padding);
147 add_footnotes_to_footer (footnotes, foot, pb);
149 header_height_ = head ? head->extent (Y_AXIS).length () : 0;
150 footer_height_ = foot ? foot->extent (Y_AXIS).length () : 0;
151 page_height_ = robust_scm2double (page->get_property ("paper-height"), 100);
154 // Initially, bottom_skyline_ represents the top of the page. Make
155 // it solid, so that the top of the first system will be forced
156 // below the top of the printable area.
157 bottom_skyline_.set_minimum_height (-header_height_);
159 SCM system_system_spacing = SCM_EOL;
160 SCM score_system_spacing = SCM_EOL;
161 SCM markup_system_spacing = SCM_EOL;
162 SCM score_markup_spacing = SCM_EOL;
163 SCM markup_markup_spacing = SCM_EOL;
165 // top_system_spacing controls the spring from the top of the printable
166 // area to the first staff. It allows the user to control the offset of
167 // the first staff (as opposed to the top of the first system) from the
168 // top of the page. Similarly for last_bottom_spacing.
169 SCM top_system_spacing = SCM_EOL;
170 SCM last_bottom_spacing = SCM_EOL;
171 if (pb && pb->paper_)
173 Output_def *paper = pb->paper_;
174 system_system_spacing = paper->c_variable ("system-system-spacing");
175 score_system_spacing = paper->c_variable ("score-system-spacing");
176 markup_system_spacing = paper->c_variable ("markup-system-spacing");
177 score_markup_spacing = paper->c_variable ("score-markup-spacing");
178 markup_markup_spacing = paper->c_variable ("markup-markup-spacing");
179 last_bottom_spacing = paper->c_variable ("last-bottom-spacing");
180 top_system_spacing = paper->c_variable ("top-system-spacing");
181 if (scm_is_pair (systems) && unsmob_prob (scm_car (systems)))
182 top_system_spacing = paper->c_variable ("top-markup-spacing");
184 // Note: the page height here does _not_ reserve space for headers and
185 // footers. This is because we want to anchor the top-system-spacing
186 // spring at the _top_ of the header.
187 page_height_ -= robust_scm2double (paper->c_variable ("top-margin"), 0)
188 + robust_scm2double (paper->c_variable ("bottom-margin"), 0);
190 read_spacing_spec (top_system_spacing, &header_padding_, ly_symbol2scm ("padding"));
191 read_spacing_spec (last_bottom_spacing, &footer_padding_, ly_symbol2scm ("padding"));
193 bool last_system_was_title = false;
196 for (SCM s = systems; scm_is_pair (s); s = scm_cdr (s))
198 bool first = (s == systems);
200 if (Grob *g = unsmob_grob (scm_car (s)))
202 System *sys = dynamic_cast<System*> (g);
205 programming_error ("got a grob for vertical spacing that wasn't a System");
209 SCM spec = system_system_spacing;
211 spec = top_system_spacing;
212 else if (last_system_was_title)
213 spec = markup_system_spacing;
214 else if (0 == Paper_column::get_rank (sys->get_bound (LEFT)))
215 spec = score_system_spacing;
217 Spring spring (0, 0);
219 Real indent = line_dimensions_int (sys->paper_score ()->layout (), sys->get_rank ())[LEFT];
220 alter_spring_from_spacing_spec (spec, &spring);
221 read_spacing_spec (spec, &padding, ly_symbol2scm ("padding"));
223 append_system (sys, spring, indent, padding);
224 last_system_was_title = false;
226 else if (Prob *p = unsmob_prob (scm_car (s)))
228 SCM spec = first ? top_system_spacing
229 : (last_system_was_title ? markup_markup_spacing : score_markup_spacing);
230 Spring spring (0, 0);
232 alter_spring_from_spacing_spec (spec, &spring);
233 read_spacing_spec (spec, &padding, ly_symbol2scm ("padding"));
235 append_prob (p, spring, padding);
236 last_system_was_title = true;
239 programming_error ("got a system that was neither a Grob nor a Prob");
242 Spring last_spring (0, 0);
243 Real last_padding = 0;
244 alter_spring_from_spacing_spec (last_bottom_spacing, &last_spring);
245 read_spacing_spec (last_bottom_spacing, &last_padding, ly_symbol2scm ("padding"));
246 last_spring.ensure_min_distance (last_padding - bottom_skyline_.max_height () + footer_height_);
247 springs_.push_back (last_spring);
249 if (elements_.size ())
251 Real bottom_padding = 0;
253 // TODO: junk bottom-space now that we have last-bottom-spacing?
254 // bottom-space has the flexibility that one can do it per-system.
255 // NOTE: bottom-space is misnamed since it is not stretchable space.
256 if (Prob *p = elements_.back ().prob)
257 bottom_padding = robust_scm2double (p->get_property ("bottom-space"), 0);
258 else if (elements_.back ().staves.size ())
260 SCM details = get_details (elements_.back ());
261 bottom_padding = robust_scm2double (ly_assoc_get (ly_symbol2scm ("bottom-space"),
266 page_height_ -= bottom_padding;
271 Page_layout_problem::set_header_height (Real height)
273 header_height_ = height;
277 Page_layout_problem::set_footer_height (Real height)
279 footer_height_ = height;
283 Page_layout_problem::append_system (System *sys, Spring const& spring, Real indent, Real padding)
285 Grob *align = sys->get_vertical_alignment ();
289 align->set_property ("positioning-done", SCM_BOOL_T);
291 extract_grob_set (align, "elements", all_elts);
292 vector<Grob*> elts = filter_dead_elements (all_elts);
293 vector<Real> minimum_offsets = Align_interface::get_minimum_translations_without_min_dist (align, elts, Y_AXIS);
294 vector<Real> minimum_offsets_with_min_dist = Align_interface::get_minimum_translations (align, elts, Y_AXIS);
296 Skyline up_skyline (UP);
297 Skyline down_skyline (DOWN);
298 build_system_skyline (elts, minimum_offsets_with_min_dist, &up_skyline, &down_skyline);
299 up_skyline.shift (indent);
300 down_skyline.shift (indent);
303 We need to call distance with skyline-horizontal-padding because
304 the system skyline-horizontal-padding is not added during the creation
305 of an individual staff. So we add the padding for the distance check
306 at the time of adding in the system.
308 Real minimum_distance = up_skyline.distance (bottom_skyline_, robust_scm2double (sys->get_property ("skyline-horizontal-padding"), 0)) + padding;
310 Spring spring_copy = spring;
311 spring_copy.ensure_min_distance (minimum_distance);
312 springs_.push_back (spring_copy);
314 bottom_skyline_ = down_skyline;
315 elements_.push_back (Element (elts, minimum_offsets, padding));
317 // Add the springs for the VerticalAxisGroups in this system.
319 // If the user has specified the offsets of the individual staves, fix the
320 // springs at the given distances. Otherwise, use stretchable springs.
321 SCM details = get_details (elements_.back ());
322 SCM manual_dists = ly_assoc_get (ly_symbol2scm ("alignment-distances"), details, SCM_EOL);
323 vsize last_spaceable_staff = 0;
324 bool found_spaceable_staff = false;
325 for (vsize i = 0; i < elts.size (); ++i)
327 if (is_spaceable (elts[i]))
329 // We don't add a spring for the first staff, since
330 // we are only adding springs _between_ staves here.
331 if (!found_spaceable_staff)
333 found_spaceable_staff = true;
334 last_spaceable_staff = i;
338 Spring spring (0.5, 0.0);
339 SCM spec = elts[last_spaceable_staff]->get_property ("staff-staff-spacing");
340 alter_spring_from_spacing_spec (spec, &spring);
342 springs_.push_back (spring);
343 Real min_distance = (found_spaceable_staff ? minimum_offsets_with_min_dist[last_spaceable_staff] : 0) - minimum_offsets_with_min_dist[i];
344 springs_.back ().ensure_min_distance (min_distance);
346 if (scm_is_pair (manual_dists))
348 if (scm_is_number (scm_car (manual_dists)))
350 Real dy = scm_to_double (scm_car (manual_dists));
352 springs_.back ().set_distance (dy);
353 springs_.back ().set_min_distance (dy);
354 springs_.back ().set_inverse_stretch_strength (0);
356 manual_dists = scm_cdr (manual_dists);
358 last_spaceable_staff = i;
362 // Corner case: there was only one staff, and it wasn't spaceable.
363 // Mark it spaceable, because we do not allow non-spaceable staves
364 // to be at the top or bottom of a system.
365 if (!found_spaceable_staff && elts.size ())
366 mark_as_spaceable (elts[0]);
370 Page_layout_problem::append_prob (Prob *prob, Spring const& spring, Real padding)
372 Skyline_pair *sky = Skyline_pair::unsmob (prob->get_property ("vertical-skylines"));
373 Real minimum_distance = 0;
374 bool tight_spacing = to_boolean (prob->get_property ("tight-spacing"));
378 minimum_distance = (*sky)[UP].distance (bottom_skyline_);
379 bottom_skyline_ = (*sky)[DOWN];
381 else if (Stencil *sten = unsmob_stencil (prob->get_property ("stencil")))
383 Interval iv = sten->extent (Y_AXIS);
384 minimum_distance = iv[UP] - bottom_skyline_.max_height ();
386 bottom_skyline_.clear ();
387 bottom_skyline_.set_minimum_height (iv[DOWN]);
390 Spring spring_copy = spring;
393 spring_copy.set_min_distance (minimum_distance);
394 spring_copy.set_inverse_stretch_strength (0.0);
395 spring_copy.set_distance (0.0);
398 spring_copy.ensure_min_distance (minimum_distance + padding);
400 springs_.push_back (spring_copy);
401 elements_.push_back (Element (prob, padding));
405 Page_layout_problem::solve_rod_spring_problem (bool ragged)
407 Simple_spacer spacer;
409 for (vsize i = 0; i < springs_.size (); ++i)
410 spacer.add_spring (springs_[i]);
412 spacer.solve (page_height_, ragged);
413 solution_ = spacer.spring_positions ();
417 Real overflow = spacer.configuration_length (spacer.force ())
419 if (ragged && overflow < 1e-6)
420 warning (_ ("cannot fit music on page: ragged-spacing was requested, but page was compressed"));
423 warning (_f ("cannot fit music on page: overflow is %f",
425 warning (_ ("compressing music to fit"));
426 vsize space_count = solution_.size ();
427 Real spacing_increment = overflow / (space_count - 2);
428 for (vsize i = 2; i < space_count; i++)
429 solution_[i] -= (i-1) * spacing_increment;
434 // The solution_ vector stores the position of every live VerticalAxisGroup
435 // and every title. From that information,
436 // 1) within each system, stretch the staves so they land at the right position
437 // 2) find the offset of each system (relative to the printable area of the page).
438 // TODO: this function is getting too long, maybe split it up?
440 Page_layout_problem::find_system_offsets ()
442 SCM system_offsets = SCM_EOL;
443 SCM *tail = &system_offsets;
445 // spring_idx 0 is the top of the page. Interesting values start from 1.
446 vsize spring_idx = 1;
447 vector<Grob*> loose_lines;
448 vector<Real> loose_line_min_distances;
449 Grob *last_spaceable_line = 0;
450 Real last_spaceable_line_translation = 0;
451 Interval last_title_extent;
452 for (vsize i = 0; i < elements_.size (); ++i)
454 if (elements_[i].prob)
456 *tail = scm_cons (scm_from_double (solution_[spring_idx]), SCM_EOL);
457 tail = SCM_CDRLOC (*tail);
458 Interval prob_extent = unsmob_stencil (elements_[i].prob->get_property ("stencil"))->extent (Y_AXIS);
460 // Lay out any non-spaceable lines between this line and
462 if (loose_lines.size ())
464 Interval loose_extent = loose_lines.back ()->extent (loose_lines.back (), Y_AXIS);
465 Real min_distance = (-loose_extent[DOWN] + prob_extent[UP]
466 + elements_[i].padding);
468 loose_line_min_distances.push_back (min_distance);
469 loose_lines.push_back (0);
471 distribute_loose_lines (loose_lines, loose_line_min_distances,
472 last_spaceable_line_translation, -solution_[spring_idx]);
473 loose_lines.clear ();
474 loose_line_min_distances.clear ();
477 last_spaceable_line = 0;
478 last_spaceable_line_translation = -solution_[spring_idx];
479 last_title_extent = prob_extent;
484 // Getting this signs right here is a little tricky. The configuration
485 // we return has zero at the top of the page and positive numbers further
486 // down, as does the solution_ vector. Within a staff, however, positive
488 // TODO: perhaps change the way the page 'configuration variable works so
489 // that it is consistent with the usual up/down sign conventions in
490 // Lilypond. Then this would be less confusing.
492 // These two positions are relative to the page (with positive numbers being
494 Real first_staff_position = solution_[spring_idx];
495 Real first_staff_min_translation = elements_[i].min_offsets.size () ? elements_[i].min_offsets[0] : 0;
496 Real system_position = first_staff_position + first_staff_min_translation;
498 // Position the staves within this system.
499 vector<Real> const& min_offsets = elements_[i].min_offsets;
500 bool found_spaceable_staff = false;
501 for (vsize staff_idx = 0; staff_idx < elements_[i].staves.size (); ++staff_idx)
503 Grob *staff = elements_[i].staves[staff_idx];
504 staff->set_property ("system-Y-offset", scm_from_double (-system_position));
506 if (is_spaceable (staff))
508 // this is relative to the system: negative numbers are down.
509 staff->translate_axis (system_position - solution_[spring_idx], Y_AXIS);
511 // Lay out any non-spaceable lines between this line and
513 if (loose_lines.size ())
516 loose_line_min_distances.push_back (min_offsets[staff_idx-1] - min_offsets[staff_idx]);
518 loose_line_min_distances.push_back (elements_[i].padding - min_offsets[staff_idx]);
519 loose_lines.push_back (staff);
521 distribute_loose_lines (loose_lines, loose_line_min_distances,
522 last_spaceable_line_translation, -solution_[spring_idx]);
523 loose_lines.clear ();
524 loose_line_min_distances.clear ();
526 last_spaceable_line = staff;
527 last_spaceable_line_translation = -solution_[spring_idx];
528 found_spaceable_staff = true;
533 if (loose_lines.empty ())
534 loose_lines.push_back (last_spaceable_line);
537 // NOTE: the way we do distances between loose lines (and other lines too, actually)
538 // is not the most accurate way possible: we only insert rods between adjacent
539 // lines. To be more accurate, we could insert rods between non-adjacent lines
540 // using a scheme similar to the one in set_column_rods.
541 loose_line_min_distances.push_back (min_offsets[staff_idx-1] - min_offsets[staff_idx]);
543 { // this is the first line in a system
545 if (loose_lines.back ())
546 // distance to the final line in the preceding system,
547 // including 'system-system-spacing 'padding
548 min_dist = (Axis_group_interface::minimum_distance (loose_lines.back (),
551 + elements_[i].padding);
552 else if (!last_title_extent.is_empty ())
553 // distance to the preceding title,
554 // including 'markup-system-spacing 'padding
555 min_dist = (staff->extent (staff, Y_AXIS)[UP] - last_title_extent[DOWN]
556 + elements_[i].padding);
557 else // distance to the top margin
558 min_dist = header_padding_ + header_height_ + staff->extent (staff, Y_AXIS)[UP];
560 loose_line_min_distances.push_back (min_dist);
562 loose_lines.push_back (staff);
566 // Corner case: even if a system has no live staves, it still takes up
567 // one spring (a system with one live staff also takes up one spring),
568 // which we need to increment past.
569 if (!found_spaceable_staff)
572 *tail = scm_cons (scm_from_double (system_position), SCM_EOL);
573 tail = SCM_CDRLOC (*tail);
577 if (loose_lines.size ())
579 Grob *last = loose_lines.back ();
580 Interval last_ext = last->extent (last, Y_AXIS);
581 loose_line_min_distances.push_back (-last_ext[DOWN] + footer_height_ + footer_padding_);
582 loose_lines.push_back (0);
584 distribute_loose_lines (loose_lines, loose_line_min_distances,
585 last_spaceable_line_translation, -page_height_);
589 assert (spring_idx == solution_.size () - 1);
590 return system_offsets;
593 // Given two lines that are already spaced (the first and last
594 // elements of loose_lines), distribute some unspaced lines between
596 // first_translation and last_translation are relative to the page.
598 Page_layout_problem::distribute_loose_lines (vector<Grob*> const &loose_lines,
599 vector<Real> const &min_distances,
600 Real first_translation, Real last_translation)
602 Simple_spacer spacer;
603 for (vsize i = 0; i + 1 < loose_lines.size (); ++i)
605 SCM spec = get_spacing_spec (loose_lines[i], loose_lines[i+1], false, 0, INT_MAX);
606 Spring spring (1.0, 0.0);
607 alter_spring_from_spacing_spec (spec, &spring);
608 spring.ensure_min_distance (min_distances[i]);
609 spacer.add_spring (spring);
612 // Remember: offsets are decreasing, since we're going from UP to DOWN!
613 spacer.solve (first_translation - last_translation, false);
615 vector<Real> solution = spacer.spring_positions ();
616 for (vsize i = 1; i + 1 < solution.size (); ++i)
618 Real system_offset = scm_to_double (loose_lines[i]->get_property ("system-Y-offset"));
619 loose_lines[i]->translate_axis (first_translation - solution[i] - system_offset, Y_AXIS);
624 Page_layout_problem::solution (bool ragged)
626 solve_rod_spring_problem (ragged);
627 return find_system_offsets ();
630 // Build upper and lower skylines for a system. We don't yet know the positions
631 // of the staves within the system, so we make the skyline as conservative as
632 // possible. That is, for the upper skyline, we pretend that all of the staves
633 // in the system are packed together close to the top system; for the lower
634 // skyline, we pretend that all of the staves are packed together close to
635 // the bottom system.
637 // The upper skyline is relative to the top staff; the lower skyline is relative to
640 Page_layout_problem::build_system_skyline (vector<Grob*> const& staves,
641 vector<Real> const& minimum_translations,
645 if (minimum_translations.empty ())
648 assert (staves.size () == minimum_translations.size ());
649 Real first_translation = minimum_translations[0];
650 Real last_spaceable_dy = 0;
651 Real first_spaceable_dy = 0;
652 bool found_spaceable_staff = false;
654 for (vsize i = 0; i < staves.size (); ++i)
656 Real dy = minimum_translations[i] - first_translation;
658 Skyline_pair *sky = Skyline_pair::unsmob (g->get_property ("vertical-skylines"));
662 up->merge ((*sky)[UP]);
666 down->merge ((*sky)[DOWN]);
669 if (is_spaceable (staves[i]))
671 if (!found_spaceable_staff)
673 found_spaceable_staff = true;
674 first_spaceable_dy = dy;
676 last_spaceable_dy = dy;
680 // Leave the up skyline at a position relative
681 // to the top spaceable staff.
682 up->raise (-first_spaceable_dy);
684 // Leave the down skyline at a position
685 // relative to the bottom spaceable staff.
686 down->raise (-last_spaceable_dy);
690 Page_layout_problem::prob_extent (Prob *p)
692 Stencil *sten = unsmob_stencil (p->get_property ("stencil"));
693 return sten ? sten->extent (Y_AXIS) : Interval (0, 0);
697 Page_layout_problem::first_staff_extent (Element const& e)
700 return prob_extent (e.prob);
701 else if (e.staves.size ())
702 return e.staves[0]->extent (e.staves[0], Y_AXIS);
704 return Interval (0, 0);
708 Page_layout_problem::last_staff_extent (Element const& e)
711 return prob_extent (e.prob);
712 else if (e.staves.size ())
713 return e.staves.back ()->extent (e.staves.back (), Y_AXIS);
715 return Interval (0, 0);
719 Page_layout_problem::get_details (Element const& elt)
721 if (elt.staves.empty ())
724 return get_details (elt.staves.back ()->get_system ());
728 Page_layout_problem::get_details (Grob *g)
730 Grob *left_bound = dynamic_cast<Spanner*> (g)->get_bound (LEFT);
731 return left_bound->get_property ("line-break-system-details");
735 Page_layout_problem::is_spaceable (Grob *g)
737 return !scm_is_number (g->get_property ("staff-affinity"));
741 Page_layout_problem::mark_as_spaceable (Grob *g)
743 g->set_property ("staff-affinity", SCM_BOOL_F);
747 Page_layout_problem::read_spacing_spec (SCM spec, Real* dest, SCM sym)
749 SCM pair = scm_sloppy_assq (sym, spec);
750 if (scm_is_pair (pair) && scm_is_number (scm_cdr (pair)))
752 *dest = scm_to_double (scm_cdr (pair));
758 // If there is a forced, fixed spacing between BEFORE and AFTER, return it.
759 // Otherwise, return -infinity_f.
760 // If after is spaceable, it is the (spaceable_index + 1)th spaceable grob in
763 Page_layout_problem::get_fixed_spacing (Grob *before, Grob *after, int spaceable_index, bool pure, int start, int end)
765 Spanner *after_sp = dynamic_cast<Spanner*> (after);
766 SCM cache_symbol = (is_spaceable (before) && is_spaceable (after))
767 ? ly_symbol2scm ("spaceable-fixed-spacing")
768 : ly_symbol2scm ("loose-fixed-spacing");
771 // The result of this function doesn't depend on "end," so we can reduce the
772 // size of the cache by ignoring it.
773 SCM cached = after_sp->get_cached_pure_property (cache_symbol, start, 0);
774 if (scm_is_number (cached))
775 return robust_scm2double (cached, 0.0);
778 Real ret = -infinity_f;
780 // If we're pure, then paper-columns have not had their systems set,
781 // and so elts[i]->get_system () is unreliable.
782 System *sys = pure ? Grob::get_system (before) : before->get_system ();
783 Grob *left_bound = sys ? sys->get_maybe_pure_bound (LEFT, pure, start, end) : 0;
785 if (is_spaceable (before) && is_spaceable (after) && left_bound)
787 SCM details = left_bound->get_property ("line-break-system-details");
788 SCM manual_dists = ly_assoc_get (ly_symbol2scm ("alignment-distances"), details, SCM_EOL);
789 if (scm_is_pair (manual_dists))
791 SCM forced = robust_list_ref (spaceable_index - 1, manual_dists);
792 if (scm_is_number (forced))
793 ret = max (ret, scm_to_double (forced));
797 // Cache the result. As above, we ignore "end."
799 after_sp->cache_pure_property (cache_symbol, start, 0, scm_from_double (ret));
805 add_stretchability (SCM alist, Real stretch)
807 if (!scm_is_pair (scm_sloppy_assq (ly_symbol2scm ("stretchability"), alist)))
808 return scm_acons (ly_symbol2scm ("stretchability"), scm_from_double (stretch), alist);
813 // We want to put a large stretch between a non-spaceable line and its
814 // non-affinity staff. We want to put an even larger stretch between
815 // a non-spaceable line and the top/bottom of the page. That way,
816 // a spacing-affinity UP line at the bottom of the page will still be
817 // placed close to its staff.
818 const double LARGE_STRETCH = 10e5;
819 const double HUGE_STRETCH = 10e7;
821 // Returns the spacing spec connecting BEFORE to AFTER.
823 Page_layout_problem::get_spacing_spec (Grob *before, Grob *after, bool pure, int start, int end)
825 // If there are no spacing wishes, return a very flexible spring.
826 // This will occur, for example, if there are lyrics at the bottom of
827 // the page, in which case we don't want the spring from the lyrics to
828 // the bottom of the page to have much effect.
829 if (!before || !after)
830 return add_stretchability (SCM_EOL, HUGE_STRETCH);
832 if (is_spaceable (before))
834 if (is_spaceable (after))
835 return before->get_maybe_pure_property ("staff-staff-spacing", pure, start, end);
838 Direction affinity = to_dir (after->get_maybe_pure_property ("staff-affinity", pure, start, end));
839 return (affinity == DOWN)
840 ? add_stretchability (after->get_maybe_pure_property ("nonstaff-unrelatedstaff-spacing", pure, start, end),
842 : after->get_maybe_pure_property ("nonstaff-relatedstaff-spacing", pure, start, end);
847 if (is_spaceable (after))
849 Direction affinity = to_dir (before->get_maybe_pure_property ("staff-affinity", pure, start, end));
850 return (affinity == UP)
851 ? add_stretchability (before->get_maybe_pure_property ("nonstaff-unrelatedstaff-spacing", pure, start, end),
853 : before->get_maybe_pure_property ("nonstaff-relatedstaff-spacing", pure, start, end);
857 Direction before_affinity = to_dir (before->get_maybe_pure_property ("staff-affinity", pure, start, end));
858 Direction after_affinity = to_dir (after->get_maybe_pure_property ("staff-affinity", pure, start, end));
859 static bool warned = false;
860 if (after_affinity > before_affinity
863 warning (_ ("staff-affinities should only decrease"));
866 if (before_affinity != UP)
867 return before->get_maybe_pure_property ("nonstaff-nonstaff-spacing", pure, start, end);
868 else if (after_affinity != DOWN)
869 return before->get_maybe_pure_property ("nonstaff-nonstaff-spacing", pure, start, end);
870 return add_stretchability (before->get_maybe_pure_property ("nonstaff-unrelatedstaff-spacing", pure, start, end),
880 Page_layout_problem::alter_spring_from_spacing_spec (SCM spec, Spring* spring)
885 if (read_spacing_spec (spec, &space, ly_symbol2scm ("basic-distance")))
886 spring->set_distance (space);
887 if (read_spacing_spec (spec, &min_dist, ly_symbol2scm ("minimum-distance")))
888 spring->set_min_distance (min_dist);
889 spring->set_default_strength ();
891 if (read_spacing_spec (spec, &stretch, ly_symbol2scm ("stretchability")))
892 spring->set_inverse_stretch_strength (stretch);
896 Page_layout_problem::filter_dead_elements (vector<Grob*> const& input)
898 vector<Grob*> output;
899 for (vsize i = 0; i < input.size (); ++i)
901 if (Hara_kiri_group_spanner::has_interface (input[i]))
902 Hara_kiri_group_spanner::consider_suicide (input[i]);
904 if (input[i]->is_live ())
905 output.push_back (input[i]);