-/*
- spacing-spanner.cc -- implement Spacing_spanner
-
- source file of the GNU LilyPond music typesetter
-
- (c) 1999--2002 Han-Wen Nienhuys <hanwen@cs.uu.nl>
-
- */
-
-
-#include "paper-column.hh"
-#include "dimensions.hh"
-#include "paper-def.hh"
-#include "warn.hh"
-#include "paper-score.hh"
-#include "line-of-score.hh"
-#include "misc.hh"
-#include "separation-item.hh"
-#include "spanner.hh"
-#include "spring.hh"
-
-class New_spacing_spanner
-{
-public:
- static void set_interface (Grob*);
- static void do_measure (Grob*,Link_array<Grob> *) ;
- static void stretch_to_regularity (Grob*, Array<Spring> *, Link_array<Grob> const &);
- static void breakable_column_spacing (Item* l, Item *r);
- DECLARE_SCHEME_CALLBACK (set_springs, (SCM ));
- static Real default_bar_spacing (Grob*,Grob*,Grob*,Moment) ;
- static Real note_spacing (Grob*,Grob*,Grob*,Moment) ;
- static Real get_duration_space (Grob*,Moment dur, Moment shortest) ;
- static void prune_loose_colunms (Link_array<Grob>*);
-};
-
-void
-New_spacing_spanner::set_interface (Grob*me)
-{
- me->set_extent_callback (SCM_EOL, X_AXIS);
- me->set_extent_callback (SCM_EOL, Y_AXIS) ;
-}
-
-/*
- Remove all columns that are not tightly
- fitting part of the spacing problem.
- */
-void
-New_spacing_spanner::prune_loose_colunms (Link_array<Grob> *cols)
-{
- for (int i = cols->size(); i--;)
- {
- SCM between = cols->elem(i)->get_grob_property ("between-cols");
- if (!gh_pair_p (between))
- continue;
-
- Item * l = dynamic_cast<Item*> (unsmob_grob (gh_car (between)));
- Item * r = dynamic_cast<Item*> (unsmob_grob (gh_cdr (between)));
- if (l->column_l () != cols->elem (i-1)
- || r->column_l () != cols->elem (i +1))
- {
- cols->del (i);
- }
- }
-}
-
-/*
-
- The algorithm is partly taken from :
-
- John S. Gourlay. ``Spacing a Line of Music,'' Technical Report
- OSU-CISRC-10/87-TR35, Department of Computer and Information
- Science, The Ohio State University, 1987.
-
- TOO HAIRY.
-
- TODO: write comments
-
- */
-void
-New_spacing_spanner::do_measure (Grob*me, Link_array<Grob> *cols)
-{
- Moment shortest_in_measure;
-
- /*
- space as if this duration is present.
- */
- Moment base_shortest_duration = *unsmob_moment (me->get_grob_property ("maximum-duration-for-spacing"));
- shortest_in_measure.set_infinite (1);
-
- prune_loose_colunms (cols);
-
- for (int i =0 ; i < cols->size (); i++)
- {
- if (Paper_column::musical_b (cols->elem (i)))
- {
- Moment *when = unsmob_moment (cols->elem (i)->get_grob_property ("when"));
-
- /*
- ignore grace notes for shortest notes.
- */
- if (when && when->grace_part_)
- continue;
-
- SCM st = cols->elem (i)->get_grob_property ("shortest-starter-duration");
- Moment this_shortest = *unsmob_moment (st);
- shortest_in_measure = shortest_in_measure <? this_shortest;
- }
- }
-
- Array<Spring> springs;
-
- Item * first_col = 0;
- for (int i= 0; i < cols->size () - 1; i++)
- {
- Item * l = dynamic_cast<Item*> (cols->elem (i));
-
- if (!first_col && Paper_column::musical_b (l))
- first_col = l;
-
- Item * r = dynamic_cast<Item*> (cols->elem (i+1));
- Paper_column * lc = dynamic_cast<Paper_column*> (l);
- Paper_column *rc = dynamic_cast<Paper_column*> (r);
-
-
-#if 0
-cout << "params for cols " << Paper_column::rank_i (l) << " " << Paper_column::rank_i (r) << endl;
- cout << " musical: " << Paper_column::musical_b (l) << " " << Paper_column::musical_b (r) << endl;
-#endif
-
- if (!Paper_column::musical_b (l))
- {
- breakable_column_spacing (l, r);
-
- l = l->find_prebroken_piece (RIGHT);
- if (l)
- breakable_column_spacing (l,r);
-
- continue ;
- }
-
- Real note_space = note_spacing (me,lc, rc, shortest_in_measure <? base_shortest_duration);
- Real hinterfleisch = note_space;
- Real headwid = gh_scm2double (me->get_grob_property ("arithmetic-multiplier"));
-
- SCM seq = lc->get_grob_property ("spacing-sequence");
-
- Moment dt = Paper_column::when_mom (r) - Paper_column::when_mom (l);
-
- /*
- hinterfleisch = hind-meat = amount of space following a note.
-
-
- We adjust the space following a note only if the next note
- happens after the current note (this is set in the grob
- property SPACING-SEQUENCE. */
-
- Real stretch_distance = note_space;
- if (shortest_in_measure <= dt)
- {
- /*
- currently SPACING-SEQUENCE is set in
- Separating_group_spanner::find_musical_sequences (), which
- works neatly for one-voice-per staff, however,
-
- it can't find out the actual duration of the notes on a
- staff, so when putting tuplets and normal patterns it gets
- confused, (ie. believes that < { c8 c8 } { d8 d8 d8 }*2/3
- > contains 1/12 notes. ).
-
- here we kludge, by checking if the distance we're spacing
- for is less than the shortest note.
-
- TODO:
-
- Move SPACING-SEQUENCE detection into a voice
- level-engraver --or-- make sure that every column has
- access to the note head.
-
- */
- for (SCM s = seq; gh_pair_p (s); s = ly_cdr (s))
- {
- Grob *lm = unsmob_grob (ly_caar (s));
- Grob *rm = unsmob_grob (ly_cdar (s));
-
- // TODO; configgable.
- hinterfleisch += -headwid + Separation_item::my_width (lm)[RIGHT] -
- 0.5 * Separation_item::my_width (rm)[LEFT];
-
- }
-
- // ? why.
- if (gh_pair_p (seq))
- stretch_distance -= headwid;
- }
- Spring s;
- s.distance_f_ = hinterfleisch;
- s.strength_f_ = 1 / stretch_distance;
-
- s.item_l_drul_[LEFT] = l;
- s.item_l_drul_[RIGHT] = r;
-
- s.add_to_cols();
- if (r->find_prebroken_piece (LEFT))
- {
- s.item_l_drul_[RIGHT] = r->find_prebroken_piece(LEFT);
- s.add_to_cols();
- }
- }
-
-}
-
-/*
- Read hints from L (todo: R) and generate springs.
- */
-void
-New_spacing_spanner::breakable_column_spacing (Item* l, Item *r)
-{
- Spring s;
-
- Real break_dist = 0.0;
- SCM espace = l->get_grob_property ("extra-space");
- if (gh_pair_p (espace))
- break_dist += gh_scm2double (ly_cdr (espace));
-
- if (!break_dist)
- break_dist = 1.0;
-
- Real break_stretch = 0.0;
-
- // todo: naming of "distance"
- espace = l->get_grob_property ("stretch-distance");
- if (gh_pair_p (espace))
- break_stretch += gh_scm2double (ly_cdr (espace));
-
- if (!break_stretch)
- break_stretch = 1.0;
-
- s.distance_f_ = break_dist;
- s.strength_f_ = 1/break_stretch;
- s.item_l_drul_[LEFT] = l;
- s.item_l_drul_[RIGHT] = r;
-
- s.add_to_cols ();
-}
-
-/*
- Look at COLS, searching for columns that have 'regular-distance-to
- set. A sequence of columns that have this property set should have
- an equal distance (an equispaced run). Extract the projected
- distance from SPRINGS, and scale SPRINGS for the equispaced run, to the
- widest space necessary.
-
-
- TODO:
-
- -- inefficient code; maybe it is easier to twiddle with the springs
- after they've become grob properties (ie. have their
- minimum-distances set)
-
- -- does not adjust strength field of the springs very well: result
- awkward spacing at the start of a line. (?)
-
- -- will be confused when there are multiple equispaced runs in a measure.
-
- -- dealing with springs for line breaks is a little tricky; in any
- case, we will only space per measure.
-
- -- we scale to actual distances, not to optical effects. Eg. if the
- equispaced run contains optical corrections, then the scaling will
- cancel those.
-
- -- Regular_spacing_engraver doesn't mark the first column of the
- next bar, making the space before a barline too short, in this case
-
-
- x<- 16ths--> x(8th)
- x(8th) x(8th) <- equispaced run.
-
-*/
-
-void
-New_spacing_spanner::stretch_to_regularity (Grob *me,
- Array<Spring> * springs,
- Link_array<Grob> const & cols)
-{
- /*
- Find the starting column of the run. REGULAR-DISTANCE-TO points
- back to a previous column, so we look ahead to find a column
- pointing back to the first one.
-
- */
- Grob * first_regular_spaced_col = 0;
- for (int i = 0 ; i < cols.size () && !first_regular_spaced_col; i++)
- {
- SCM rdt = cols[i]->get_grob_property ("regular-distance-to");
- if (cols.find_l (dynamic_cast<Item*> (unsmob_grob (rdt))))
- first_regular_spaced_col = unsmob_grob (rdt);
- }
- for (int i = springs->size (); i-- ;)
- springs->elem (i).set_to_cols ();
-
- int i;
- for (i = 0; i < springs->size ()
- && springs->elem (i).item_l_drul_[RIGHT] != first_regular_spaced_col;
- i++)
- ;
-
-
- if (i==springs->size ())
- return ;
-
- Real maxdist = 0.0;
- Real dist =0.0;
- Grob *last_col = first_regular_spaced_col;
- Grob *last_regular_spaced_col = first_regular_spaced_col;
-
-
- /*
- find the max distance for this run.
- */
- for (int j = i; j < springs->size (); j++)
- {
- Spring *s = &(springs->elem_ref (j));
- if (s->item_l_drul_[LEFT] != last_col)
- continue;
-
- dist += s->distance_f_;
-
- last_col = s->item_l_drul_[RIGHT];
- SCM rdt = last_col->get_grob_property ("regular-distance-to");
- if (unsmob_grob (rdt) == last_regular_spaced_col)
- {
- maxdist = maxdist >? dist;
- dist = 0.0;
- last_regular_spaced_col = last_col;
- }
-
- }
-
- /*
- Scale the springs
- */
- dist =0.0;
- last_col = first_regular_spaced_col;
- last_regular_spaced_col = first_regular_spaced_col;
- for (int j = i; j < springs->size (); j++)
- {
- Spring *s = &springs->elem_ref (j);
- if (s->item_l_drul_[LEFT] != last_col)
- continue;
- dist += s->distance_f_;
-
- last_col = s->item_l_drul_[RIGHT];
- SCM rdt = last_col->get_grob_property ("regular-distance-to");
- if (unsmob_grob (rdt) == last_regular_spaced_col)
- {
- do {
- springs->elem_ref (i).distance_f_ *= maxdist / dist;
- springs->elem_ref (i).strength_f_ *= dist / maxdist;
- } while (i++ < j);
- last_regular_spaced_col = last_col;
- dist =0.0;
- }
- }
-}
-
-/**
- Do something if breakable column has no spacing hints set.
- */
-Real
-New_spacing_spanner::default_bar_spacing (Grob*me, Grob *lc, Grob *rc,
- Moment shortest)
-{
- Real symbol_distance = lc->extent (lc,X_AXIS)[RIGHT] ;
- Real durational_distance = 0;
- Moment delta_t = Paper_column::when_mom (rc) - Paper_column::when_mom (lc);
-
- /*
- ugh should use shortest_playing distance
- */
- if (delta_t.to_bool ())
- {
- durational_distance = get_duration_space (me, delta_t, shortest);
- }
-
- return symbol_distance >? durational_distance;
-}
-
-
-/**
- Get the measure wide ant for arithmetic spacing.
-
- @see
- John S. Gourlay. ``Spacing a Line of Music,'' Technical Report
- OSU-CISRC-10/87-TR35, Department of Computer and Information Science,
- The Ohio State University, 1987.
-
- */
-Real
-New_spacing_spanner::get_duration_space (Grob*me, Moment d, Moment shortest)
-{
- Real log = log_2 (shortest.main_part_);
- Real k = gh_scm2double (me->get_grob_property ("arithmetic-basicspace"))
- - log;
-
- Rational compdur = d.main_part_ + d.grace_part_ /Rational (3);
-
- return (log_2 (compdur) + k) * gh_scm2double (me->get_grob_property ("arithmetic-multiplier"));
-}
-
-
-Real
-New_spacing_spanner::note_spacing (Grob*me, Grob *lc, Grob *rc,
- Moment shortest)
-{
- Moment shortest_playing_len = 0;
- SCM s = lc->get_grob_property ("shortest-playing-duration");
-
-
- if (unsmob_moment (s))
- shortest_playing_len = *unsmob_moment (s);
-
- if (! shortest_playing_len.to_bool ())
- {
- programming_error ("can't find a ruling note at " + Paper_column::when_mom (lc).str ());
- shortest_playing_len = 1;
- }
-
- if (! shortest.to_bool ())
- {
- programming_error ("no minimum in measure at " + Paper_column::when_mom (lc).str ());
- shortest = 1;
- }
- Moment delta_t = Paper_column::when_mom (rc) - Paper_column::when_mom (lc);
- Real dist = 0.0;
-
- if (delta_t.main_part_)
- {
- dist = get_duration_space (me, shortest_playing_len, shortest);
- dist *= (double) (delta_t.main_part_ / shortest_playing_len.main_part_);
- }
- else if (delta_t.grace_part_)
- {
- dist = get_duration_space (me, shortest, shortest);
-
- Real grace_fact = 1.0;
- SCM gf = me->get_grob_property ("grace-space-factor");
- if (gh_number_p (gf))
- grace_fact = gh_scm2double (gf);
-
- dist *= grace_fact;
- }
-
-#if 0
- /*
- TODO: figure out how to space grace notes.
- */
-
- dist *=
- + grace_fact * (double) (delta_t.grace_part_ / shortest_playing_len.main_part_);
-
-
- Moment *lm = unsmob_moment (lc->get_grob_property ("when"));
- Moment *rm = unsmob_moment (rc->get_grob_property ("when"));
-
- if (lm && rm)
- {
- if (lm->grace_part_ && rm->grace_part_)
- dist *= 0.5;
- else if (!rm->grace_part_ && lm->grace_part_)
- dist *= 0.7;
- }
-#endif
-
- return dist;
-}
-
-
-
-MAKE_SCHEME_CALLBACK (New_spacing_spanner, set_springs,1);
-SCM
-New_spacing_spanner::set_springs (SCM smob)
-{
- Grob *me = unsmob_grob (smob);
- Link_array<Grob> all (me->pscore_l_->line_l_->column_l_arr ()) ;
-
- int j = 0;
-
- for (int i = 1; i < all.size (); i++)
- {
- Grob *sc = all[i];
- if (Item::breakable_b (sc))
- {
- Link_array<Grob> measure (all.slice (j, i+1));
- do_measure (me, &measure);
- j = i;
- }
- }
-
- /*
- farewell, cruel world
- */
- me->suicide ();
- return SCM_UNSPECIFIED;
-}
-
-
-
-/*
- maximum-duration-for-spacing
-From: bf250@freenet.carleton.ca (John Sankey)
-To: gnu-music-discuss@gnu.org
-Subject: note spacing suggestion
-Date: Mon, 10 Jul 2000 11:28:03 -0400 (EDT)
-
-Currently, Lily spaces notes by starting with a basic distance,
-arithmetic_multiplier, which it applies to the minimum duration note
-of the bar. Then she adds a logarithmic increment, scaled from
-arithmetic_basicspace, for longer notes. (Then, columns are aligned
-and justified.) Fundamentally, this matches visual spacing to musical
-weight and works well.
-
-A lot of the time in music, I see a section basically in melodic
-notes that occasionally has a rapid ornamental run (scale). So, there
-will be a section in 1/4 notes, then a brief passage in 1/32nds, then
-a return to long notes. Currently, Lily gives the same horizontal
-space to the 1/32nd notes in their bar (even if set in small size as
-is commonly done for cadenzii) as she gives to 1/4 notes in bars
-where 1/4 note is the minimum duration. The resulting visual weight
-does not match the musical weight over the page.
-
-Looking at the music I am typesetting, I feel that Lily's spacing
-could be significantly improved if, with no change in the basic
-method used, arithmetic_multiplier could be applied referred to the
-same duration throughout a piece. Of course, the current method
-should be retained for those who have already set music in it, so I
-suggest a property called something like arithmetic_base=16 to fix
-1/16 duration as the reference for arithmetic_multiplier; the default
-would be a dynamic base is it is now.
-
-Does anyone else feel that this would be a useful improvement for
-their music? (Of course, if arithmetic_multiplier became a regular
-property, this could be used to achieve a similar result by
-tweaking.)
-
- */