X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=lily%2Faxis-group-interface.cc;h=efed220b256c72639d9cd14538fc94686a61fa32;hb=f420654e26a36d5f70580490d42ad3063ab2dba7;hp=6a336f1efe448f0f79573e4593509e398647cdec;hpb=2ec5f924eb75dfc6b584a8df25a03bdfde31fc6c;p=lilypond.git diff --git a/lily/axis-group-interface.cc b/lily/axis-group-interface.cc index 6a336f1efe..efed220b25 100644 --- a/lily/axis-group-interface.cc +++ b/lily/axis-group-interface.cc @@ -1,129 +1,677 @@ -/* - axis-group-interface.cc -- implement Axis_group_interface - +/* + axis-group-interface.cc -- implement Axis_group_interface + source file of the GNU LilyPond music typesetter - - (c) 2000--2004 Han-Wen Nienhuys - - */ + + (c) 2000--2007 Han-Wen Nienhuys +*/ #include "axis-group-interface.hh" + +#include "align-interface.hh" +#include "directional-element-interface.hh" +#include "pointer-group-interface.hh" +#include "grob-array.hh" #include "hara-kiri-group-spanner.hh" +#include "international.hh" +#include "lookup.hh" +#include "paper-column.hh" +#include "paper-score.hh" +#include "separation-item.hh" +#include "skyline-pair.hh" +#include "stencil.hh" +#include "system.hh" +#include "warn.hh" void -Axis_group_interface::add_element (Grob*me,Grob *e) +Axis_group_interface::add_element (Grob *me, Grob *e) { - for (SCM ax = me->get_property ("axes"); ax != SCM_EOL ; ax = scm_cdr (ax)) + SCM axes = me->get_property ("axes"); + if (!scm_is_pair (axes)) + programming_error ("axes should be nonempty"); + + for (SCM ax = axes; scm_is_pair (ax); ax = scm_cdr (ax)) { Axis a = (Axis) scm_to_int (scm_car (ax)); - + if (!e->get_parent (a)) e->set_parent (me, a); - e->internal_set_property ((a == X_AXIS) - ? ly_symbol2scm ("axis-group-parent-X") - : ly_symbol2scm ("axis-group-parent-Y"), - me->self_scm () - ); + e->set_object ((a == X_AXIS) + ? ly_symbol2scm ("axis-group-parent-X") + : ly_symbol2scm ("axis-group-parent-Y"), + me->self_scm ()); } - + + /* must be ordered, because Align_interface also uses + Axis_group_interface */ Pointer_group_interface::add_grob (me, ly_symbol2scm ("elements"), e); - me->add_dependency (e); } bool -Axis_group_interface::has_axis (Grob*me,Axis a) +Axis_group_interface::has_axis (Grob *me, Axis a) { - /* - urg. FIXME, check for Hara_kiri_group_spanner shouldn't be necessary? - */ - return me->has_extent_callback (group_extent_callback_proc, a) || - (me->has_extent_callback (Hara_kiri_group_spanner::y_extent_proc, a)); + SCM axes = me->get_property ("axes"); + + return (SCM_BOOL_F != scm_memq (scm_from_int (a), axes)); } Interval -Axis_group_interface::relative_group_extent (Axis a, Grob *common, SCM elts) +Axis_group_interface::relative_group_extent (vector const &elts, + Grob *common, Axis a) { Interval r; - for (SCM s = elts; scm_is_pair (s); s = scm_cdr (s)) + for (vsize i = 0; i < elts.size (); i++) { - Grob * se = unsmob_grob (scm_car (s)); - Interval dims = se->extent (common, a); - if (!dims.is_empty ()) - r.unite (dims); + Grob *se = elts[i]; + if (!to_boolean (se->get_property ("cross-staff"))) + { + Interval dims = se->extent (common, a); + if (!dims.is_empty ()) + r.unite (dims); + } } return r; } -MAKE_SCHEME_CALLBACK (Axis_group_interface,group_extent_callback,2); + +/* + FIXME: pure extent handling has a lot of ad-hoc caching. + This should be done with grob property callbacks. + + --hwn +*/ + +Interval +Axis_group_interface::cached_pure_height (Grob *me, int start, int end) +{ + Paper_score *ps = get_root_system (me)->paper_score (); + vector breaks = ps->get_break_indices (); + vector cols = ps->get_columns (); + + SCM extents = me->get_property ("adjacent-pure-heights"); + + if (!scm_is_vector (extents)) + return Interval (0, 0); + + Interval ext; + for (vsize i = 0; i + 1 < breaks.size (); i++) + { + int r = Paper_column::get_rank (cols[breaks[i]]); + if (r >= end) + break; + + if (r >= start) + ext.unite (ly_scm2interval (scm_c_vector_ref (extents, i))); + } + + return ext; +} + +MAKE_SCHEME_CALLBACK (Axis_group_interface, adjacent_pure_heights, 1) SCM -Axis_group_interface::group_extent_callback (SCM element_smob, SCM scm_axis) +Axis_group_interface::adjacent_pure_heights (SCM smob) +{ + Grob *me = unsmob_grob (smob); + + Grob *common = calc_pure_elts_and_common (me); + extract_grob_set (me, "pure-relevant-items", items); + extract_grob_set (me, "pure-relevant-spanners", spanners); + + Paper_score *ps = get_root_system (me)->paper_score (); + vector breaks = ps->get_break_indices (); + vector cols = ps->get_columns (); + + SCM ret = scm_c_make_vector (breaks.size () - 1, SCM_EOL); + vsize it_index = 0; + for (vsize i = 0; i + 1 < breaks.size (); i++) + { + int start = Paper_column::get_rank (cols[breaks[i]]); + int end = Paper_column::get_rank (cols[breaks[i+1]]); + Interval iv; + + for (vsize j = it_index; j < items.size (); j++) + { + Item *it = dynamic_cast (items[j]); + int rank = it->get_column ()->get_rank (); + + if (rank <= end && it->pure_is_visible (start, end) + && !to_boolean (it->get_property ("cross-staff"))) + { + Interval dims = items[j]->pure_height (common, start, end); + if (!dims.is_empty ()) + iv.unite (dims); + } + + if (rank < end) + it_index++; + else if (rank > end) + break; + } + + for (vsize j = 0; j < spanners.size (); j++) + { + Interval_t rank_span = spanners[j]->spanned_rank_interval (); + if (rank_span[LEFT] <= end && rank_span[RIGHT] >= start + && !to_boolean (spanners[j]->get_property ("cross-staff"))) + { + Interval dims = spanners[j]->pure_height (common, start, end); + if (!dims.is_empty ()) + iv.unite (dims); + } + } + + scm_vector_set_x (ret, scm_from_int (i), ly_interval2scm (iv)); + } + return ret; +} + +Interval +Axis_group_interface::relative_pure_height (Grob *me, int start, int end) { - Grob *me = unsmob_grob (element_smob); - Axis a = (Axis) scm_to_int (scm_axis); + /* It saves a _lot_ of time if we assume a VerticalAxisGroup is additive + (ie. height (i, k) = max (height (i, j) height (j, k)) for all i <= j <= k). + Unfortunately, it isn't always true, particularly if there is a + VerticalAlignment somewhere in the descendants. - SCM elts = me->get_property ("elements"); - Grob * common = common_refpoint_of_list (elts, me, a); + Apart from PianoStaff, which has a fixed VerticalAlignment so it doesn't + count, the only VerticalAlignment comes from Score. This makes it + reasonably safe to assume that if our parent is a VerticalAlignment, + we can assume additivity and cache things nicely. */ + Grob *p = me->get_parent (Y_AXIS); + if (p && Align_interface::has_interface (p)) + return Axis_group_interface::cached_pure_height (me, start, end); + + Grob *common = calc_pure_elts_and_common (me); + extract_grob_set (me, "pure-relevant-items", items); + extract_grob_set (me, "pure-relevant-spanners", spanners); + + Interval r; + + for (vsize i = 0; i < items.size (); i++) + { + Item *it = dynamic_cast (items[i]); + int rank = it->get_column ()->get_rank (); + + if (rank > end) + break; + else if (rank >= start && it->pure_is_visible (start, end) + && !to_boolean (it->get_property ("cross-staff"))) + { + Interval dims = it->pure_height (common, start, end); + if (!dims.is_empty ()) + r.unite (dims); + } + } + + for (vsize i = 0; i < spanners.size (); i++) + { + Interval_t rank_span = spanners[i]->spanned_rank_interval (); + if (rank_span[LEFT] <= end && rank_span[RIGHT] >= start + && !to_boolean (spanners[i]->get_property ("cross-staff"))) + { + Interval dims = spanners[i]->pure_height (common, start, end); + if (!dims.is_empty ()) + r.unite (dims); + } + } + return r; +} + +MAKE_SCHEME_CALLBACK (Axis_group_interface, width, 1); +SCM +Axis_group_interface::width (SCM smob) +{ + Grob *me = unsmob_grob (smob); + return generic_group_extent (me, X_AXIS); +} + +MAKE_SCHEME_CALLBACK (Axis_group_interface, height, 1); +SCM +Axis_group_interface::height (SCM smob) +{ + Grob *me = unsmob_grob (smob); + return generic_group_extent (me, Y_AXIS); +} + +MAKE_SCHEME_CALLBACK (Axis_group_interface, pure_height, 3); +SCM +Axis_group_interface::pure_height (SCM smob, SCM start_scm, SCM end_scm) +{ + int start = robust_scm2int (start_scm, 0); + int end = robust_scm2int (end_scm, INT_MAX); + Grob *me = unsmob_grob (smob); + + /* Maybe we are in the second pass of a two-pass spacing run. In that + case, the Y-extent of a system is already given to us */ + System *system = dynamic_cast (me); + if (system) + { + SCM line_break_details = system->column (start)->get_property ("line-break-system-details"); + SCM system_y_extent = scm_assq (ly_symbol2scm ("system-Y-extent"), line_break_details); + if (scm_is_pair (system_y_extent)) + return scm_cdr (system_y_extent); + } + + return ly_interval2scm (pure_group_height (me, start, end)); +} + +MAKE_SCHEME_CALLBACK (Axis_group_interface, calc_skylines, 1); +SCM +Axis_group_interface::calc_skylines (SCM smob) +{ + Grob *me = unsmob_grob (smob); + extract_grob_set (me, "elements", elts); + Skyline_pair skylines = skyline_spacing (me, elts); + + return skylines.smobbed_copy (); +} + +/* whereas calc_skylines calculates skylines for axis-groups with a lot of + visible children, combine_skylines is designed for axis-groups whose only + children are other axis-groups (ie. VerticalAlignment). Rather than + calculating all the skylines from scratch, we just merge the skylines + of the children. +*/ +MAKE_SCHEME_CALLBACK (Axis_group_interface, combine_skylines, 1); +SCM +Axis_group_interface::combine_skylines (SCM smob) +{ + Grob *me = unsmob_grob (smob); + extract_grob_set (me, "elements", elements); + Grob *y_common = common_refpoint_of_array (elements, me, Y_AXIS); + Grob *x_common = common_refpoint_of_array (elements, me, X_AXIS); + + if (y_common != me) + programming_error ("combining skylines that don't belong to me"); + + Skyline_pair ret; + for (vsize i = 0; i < elements.size (); i++) + { + SCM skyline_scm = elements[i]->get_property ("vertical-skylines"); + if (Skyline_pair::unsmob (skyline_scm)) + { + Real offset = elements[i]->relative_coordinate (y_common, Y_AXIS); + Skyline_pair other = *Skyline_pair::unsmob (skyline_scm); + other.raise (offset); + other.shift (elements[i]->relative_coordinate (x_common, X_AXIS)); + ret.merge (other); + } + } + return ret.smobbed_copy (); +} + +SCM +Axis_group_interface::generic_group_extent (Grob *me, Axis a) +{ + /* trigger the callback to do skyline-spacing on the children */ + if (a == Y_AXIS) + (void) me->get_property ("vertical-skylines"); + + extract_grob_set (me, "elements", elts); + Grob *common = common_refpoint_of_array (elts, me, a); Real my_coord = me->relative_coordinate (common, a); - Interval r (relative_group_extent (a, common, elts)); + Interval r (relative_group_extent (elts, common, a)); return ly_interval2scm (r - my_coord); } -void -Axis_group_interface::set_axes (Grob*me,Axis a1, Axis a2) +/* This is like generic_group_extent, but it only counts the grobs that + are children of some other axis-group. This is uncached; if it becomes + commonly used, it may be necessary to cache it somehow. */ +Interval +Axis_group_interface::staff_extent (Grob *me, Grob *refp, Axis ext_a, Grob *staff, Axis parent_a) { - SCM sa1= scm_int2num (a1); - SCM sa2 = scm_int2num (a2); + extract_grob_set (me, "elements", elts); + vector new_elts; - SCM axes = me->get_property ("axes"); + for (vsize i = 0; i < elts.size (); i++) + if (elts[i]->common_refpoint (staff, parent_a) == staff) + new_elts.push_back (elts[i]); + + return relative_group_extent (new_elts, refp, ext_a); +} + + +Grob * +Axis_group_interface::calc_pure_elts_and_common (Grob *me) +{ + if (Grob *c = unsmob_grob (me->get_object ("pure-Y-common"))) + return c; + + extract_grob_set (me, "elements", elts); + + vector relevant_items; + vector relevant_spanners; + SCM pure_relevant_p = ly_lily_module_constant ("pure-relevant?"); + + for (vsize i = 0; i < elts.size (); i++) + { + if (to_boolean (scm_apply_1 (pure_relevant_p, elts[i]->self_scm (), SCM_EOL))) + { + if (dynamic_cast (elts[i])) + relevant_items.push_back (elts[i]); + else if (dynamic_cast (elts[i])) + relevant_spanners.push_back (elts[i]); + } + + + Item *it = dynamic_cast (elts[i]); + Direction d = LEFT; + if (it) + do + { + Item *piece = it->find_prebroken_piece (d); + if (piece && to_boolean (scm_apply_1 (pure_relevant_p, piece->self_scm (), SCM_EOL))) + relevant_items.push_back (piece); + } + while (flip (&d) != LEFT); + } + vector_sort (relevant_items, Item::less); + + Grob *common = common_refpoint_of_array (relevant_items, me, Y_AXIS); + common = common_refpoint_of_array (relevant_spanners, common, Y_AXIS); + + me->set_object ("pure-Y-common", common->self_scm ()); - if (!scm_is_pair (axes) - || scm_c_memq (sa1, axes) == SCM_BOOL_F - || scm_c_memq (sa2, axes) == SCM_BOOL_F) + SCM items_scm = Grob_array::make_array (); + SCM spanners_scm = Grob_array::make_array (); + + unsmob_grob_array (items_scm)->set_array (relevant_items); + unsmob_grob_array (spanners_scm)->set_array (relevant_spanners); + me->set_object ("pure-relevant-items", items_scm); + me->set_object ("pure-relevant-spanners", spanners_scm); + + return common; +} + +SCM +Axis_group_interface::calc_common (Grob *me, Axis axis) +{ + extract_grob_set (me, "elements", elts); + Grob *common = common_refpoint_of_array (elts, me, axis); + if (!common) { - SCM ax = scm_cons (sa1, SCM_EOL); - if (a1 != a2) - ax= scm_cons (sa2, ax); - me->set_property ("axes", ax); + me->programming_error ("No common parent found in calc_common axis."); + return SCM_EOL; } + + return common->self_scm (); +} + + +MAKE_SCHEME_CALLBACK (Axis_group_interface, calc_x_common, 1); +SCM +Axis_group_interface::calc_x_common (SCM grob) +{ + return calc_common (unsmob_grob (grob), X_AXIS); +} - if (a1 != X_AXIS && a2 != X_AXIS) - me->set_extent (SCM_EOL, X_AXIS); - if (a1 != Y_AXIS && a2 != Y_AXIS) - me->set_extent (SCM_EOL, Y_AXIS); +MAKE_SCHEME_CALLBACK (Axis_group_interface, calc_y_common, 1); +SCM +Axis_group_interface::calc_y_common (SCM grob) +{ + return calc_common (unsmob_grob (grob), Y_AXIS); +} - /* - why so convoluted ? (fixme/documentme?) - */ - if (me->has_extent_callback (Grob::stencil_extent_proc, a1)) - me->set_extent (Axis_group_interface::group_extent_callback_proc,a1); - if (me->has_extent_callback (Grob::stencil_extent_proc, a2)) - me->set_extent (Axis_group_interface::group_extent_callback_proc,a2); +Interval +Axis_group_interface::pure_group_height (Grob *me, int start, int end) +{ + Grob *common = calc_pure_elts_and_common (me); + + Real my_coord = me->relative_coordinate (common, Y_AXIS); + Interval r (relative_pure_height (me, start, end)); + + return r - my_coord; } -Link_array -Axis_group_interface::get_children (Grob*me) +void +Axis_group_interface::get_children (Grob *me, vector *found) { - Link_array childs; - childs.push (me) ; + found->push_back (me); if (!has_interface (me)) - return childs; - - for (SCM ep = me->get_property ("elements"); scm_is_pair (ep); ep = scm_cdr (ep)) + return; + + extract_grob_set (me, "elements", elements); + for (vsize i = 0; i < elements.size (); i++) { - Grob* e = unsmob_grob (scm_car (ep)); - if (e) - childs.concat (Axis_group_interface::get_children (e)); + Grob *e = elements[i]; + Axis_group_interface::get_children (e, found); } - - return childs; } +bool +staff_priority_less (Grob * const &g1, Grob * const &g2) +{ + Real priority_1 = robust_scm2double (g1->get_property ("outside-staff-priority"), -infinity_f); + Real priority_2 = robust_scm2double (g2->get_property ("outside-staff-priority"), -infinity_f); + + if (priority_1 < priority_2) + return true; + else if (priority_1 > priority_2) + return false; + + /* if neither grob has an outside-staff priority, the ordering will have no + effect -- we just need to choose a consistent ordering. We do this to + avoid the side-effect of calculating extents. */ + if (isinf (priority_1)) + return g1 < g2; + + /* if there is no preference in staff priority, choose the left-most one */ + Grob *common = g1->common_refpoint (g2, X_AXIS); + Real start_1 = g1->extent (common, X_AXIS)[LEFT]; + Real start_2 = g2->extent (common, X_AXIS)[LEFT]; + return start_1 < start_2; +} + +static void +add_boxes (Grob *me, Grob *x_common, Grob *y_common, vector *const boxes, Skyline_pair *skylines) +{ + /* if a child has skylines, use them instead of the extent box */ + if (Skyline_pair *pair = Skyline_pair::unsmob (me->get_property ("vertical-skylines"))) + { + Skyline_pair s = *pair; + s.shift (me->relative_coordinate (x_common, X_AXIS)); + s.raise (me->relative_coordinate (y_common, Y_AXIS)); + skylines->merge (s); + } + else if (Grob_array *elements = unsmob_grob_array (me->get_object ("elements"))) + { + for (vsize i = 0; i < elements->size (); i++) + add_boxes (elements->grob (i), x_common, y_common, boxes, skylines); + } + else if (!scm_is_number (me->get_property ("outside-staff-priority")) + && !to_boolean (me->get_property ("cross-staff"))) + { + boxes->push_back (Box (me->extent (x_common, X_AXIS), + me->extent (y_common, Y_AXIS))); + } +} + +/* We want to avoid situations like this: + still more text + more text + text + ------------------- + staff + ------------------- + + The point is that "still more text" should be positioned under + "more text". In order to achieve this, we place the grobs in several + passes. We keep track of the right-most horizontal position that has been + affected by the current pass so far (actually we keep track of 2 + positions, one for above the staff, one for below). + + In each pass, we loop through the unplaced grobs from left to right. + If the grob doesn't overlap the right-most affected position, we place it + (and then update the right-most affected position to point to the right + edge of the just-placed grob). Otherwise, we skip it until the next pass. +*/ +static void +add_grobs_of_one_priority (Skyline_pair *const skylines, + vector elements, + Grob *x_common, + Grob *y_common) +{ + vector boxes; + Drul_array last_affected_position; + + reverse (elements); + while (!elements.empty ()) + { + last_affected_position[UP] = -infinity_f; + last_affected_position[DOWN] = -infinity_f; + /* do one pass */ + for (vsize i = elements.size (); i--;) + { + Direction dir = get_grob_direction (elements[i]); + if (dir == CENTER) + { + warning (_ ("an outside-staff object should have a direction, defaulting to up")); + dir = UP; + } + + Box b (elements[i]->extent (x_common, X_AXIS), + elements[i]->extent (y_common, Y_AXIS)); + SCM horizon_padding_scm = elements[i]->get_property ("outside-staff-horizontal-padding"); + Real horizon_padding = robust_scm2double (horizon_padding_scm, 0.0); + + if (b[X_AXIS][LEFT] - 2*horizon_padding < last_affected_position[dir]) + continue; + + if (!b[X_AXIS].is_empty () && !b[Y_AXIS].is_empty ()) + { + boxes.clear (); + boxes.push_back (b); + Skyline other = Skyline (boxes, horizon_padding, X_AXIS, -dir); + Real padding = robust_scm2double (elements[i]->get_property ("outside-staff-padding"), 0.5); + Real dist = (*skylines)[dir].distance (other) + padding; + + if (dist > 0) + { + b.translate (Offset (0, dir*dist)); + elements[i]->translate_axis (dir*dist, Y_AXIS); + } + (*skylines)[dir].insert (b, 0, X_AXIS); + elements[i]->set_property ("outside-staff-priority", SCM_BOOL_F); + last_affected_position[dir] = b[X_AXIS][RIGHT]; + } + + /* + Ugh: quadratic. --hwn + */ + elements.erase (elements.begin () + i); + } + } +} + +// TODO: it is tricky to correctly handle skyline placement of cross-staff grobs. +// For example, cross-staff beams cannot be formatted until the distance between +// staves is known and therefore any grobs that depend on the beam cannot be placed +// until the skylines are known. On the other hand, the distance between staves should +// really depend on position of the cross-staff grobs that lie between them. +// Currently, we just leave cross-staff grobs out of the +// skyline altogether, but this could mean that staves are placed so close together +// that there is no room for the cross-staff grob. It also means, of course, that +// we don't get the benefits of skyline placement for cross-staff grobs. +Skyline_pair +Axis_group_interface::skyline_spacing (Grob *me, vector elements) +{ + /* For grobs with an outside-staff-priority, the sorting function might + call extent and cause suicide. This breaks the contract that is required + for the STL sort function. To avoid this, we make sure that any suicides + are triggered beforehand. + */ + for (vsize i = 0; i < elements.size (); i++) + if (scm_is_number (elements[i]->get_property ("outside-staff-priority"))) + elements[i]->extent (elements[i], X_AXIS); + + vector_sort (elements, staff_priority_less); + Grob *x_common = common_refpoint_of_array (elements, me, X_AXIS); + Grob *y_common = common_refpoint_of_array (elements, me, Y_AXIS); + + assert (y_common == me); + + vsize i = 0; + vector boxes; + + Skyline_pair skylines; + for (i = 0; i < elements.size () + && !scm_is_number (elements[i]->get_property ("outside-staff-priority")); i++) + if (!to_boolean (elements[i]->get_property ("cross-staff"))) + add_boxes (elements[i], x_common, y_common, &boxes, &skylines); + + SCM padding_scm = me->get_property ("skyline-horizontal-padding"); + Real padding = robust_scm2double (padding_scm, 0.1); + skylines.merge (Skyline_pair (boxes, padding, X_AXIS)); + for (; i < elements.size (); i++) + { + if (to_boolean (elements[i]->get_property ("cross-staff"))) + continue; + + SCM priority = elements[i]->get_property ("outside-staff-priority"); + vector current_elts; + current_elts.push_back (elements[i]); + while (i + 1 < elements.size () + && scm_eq_p (elements[i+1]->get_property ("outside-staff-priority"), priority)) + current_elts.push_back (elements[++i]); + + add_grobs_of_one_priority (&skylines, current_elts, x_common, y_common); + } + skylines.shift (-me->relative_coordinate (x_common, X_AXIS)); + return skylines; +} + +MAKE_SCHEME_CALLBACK (Axis_group_interface, calc_max_stretch, 1) +SCM +Axis_group_interface::calc_max_stretch (SCM smob) +{ + Grob *me = unsmob_grob (smob); + Real ret = 0; + extract_grob_set (me, "elements", elts); + + for (vsize i = 0; i < elts.size (); i++) + if (Axis_group_interface::has_interface (elts[i])) + ret += robust_scm2double (elts[i]->get_property ("max-stretch"), 0.0); + + return scm_from_double (ret); +} + +MAKE_SCHEME_CALLBACK (Axis_group_interface, print, 1) +SCM +Axis_group_interface::print (SCM smob) +{ + if (!debug_skylines) + return SCM_BOOL_F; + + Grob *me = unsmob_grob (smob); + Stencil ret; + if (Skyline_pair *s = Skyline_pair::unsmob (me->get_property ("vertical-skylines"))) + { + ret.add_stencil (Lookup::points_to_line_stencil (0.1, (*s)[UP].to_points (X_AXIS)) + .in_color (255, 0, 255)); + ret.add_stencil (Lookup::points_to_line_stencil (0.1, (*s)[DOWN].to_points (X_AXIS)) + .in_color (0, 255, 255)); + } + return ret.smobbed_copy (); +} +ADD_INTERFACE (Axis_group_interface, + "An object that groups other layout objects.", -ADD_INTERFACE (Axis_group_interface, "axis-group-interface", - "An object that groups other layout objects.", - "axes elements"); + /* properties */ + "X-common " + "Y-common " + "adjacent-pure-heights " + "axes " + "elements " + "keep-fixed-while-stretching " + "max-stretch " + "no-alignment " + "pure-Y-common " + "pure-relevant-items " + "pure-relevant-spanners " + "vertical-skylines " + );