/*
- simple-spacer.cc -- implement Simple_spacer
+ This file is part of LilyPond, the GNU music typesetter.
- source file of the GNU LilyPond music typesetter
-
- (c) 1999--2006 Han-Wen Nienhuys <hanwen@xs4all.nl>
+ Copyright (C) 1999--2010 Han-Wen Nienhuys <hanwen@xs4all.nl>
TODO:
- add support for different stretch/shrink constants?
+
+ LilyPond is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ LilyPond is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with LilyPond. If not, see <http://www.gnu.org/licenses/>.
*/
#include <cstdio>
Simple_spacer::Simple_spacer ()
{
- /*
- Give an extra penalty for compression. Needed to avoid compressing
- tightly spaced lines.
- */
- active_count_ = 0;
- force_ = 0.;
- indent_ = 0.0;
- default_space_ = 20 PT;
+ line_len_ = 0.0;
+ force_ = 0.0;
+ fits_ = true;
+ ragged_ = true;
+}
+
+Real
+Simple_spacer::force () const
+{
+ return force_;
+}
+
+bool
+Simple_spacer::fits () const
+{
+ return fits_;
+}
+
+Real
+Simple_spacer::rod_force (int l, int r, Real dist)
+{
+ Real d = range_ideal_len (l, r);
+ Real c = range_stiffness (l, r, dist > d);
+ Real block_stretch = dist - d;
+
+ if (isinf (c) && block_stretch == 0) /* take care of the 0*infinity_f case */
+ return 0;
+ return c * block_stretch;
}
void
return;
}
- Real c = range_stiffness (l, r);
- if (isinf (c))
+ Real block_force = rod_force (l, r, dist);
+
+ if (isinf (block_force))
{
- /*
- If a spring is fixed, we have to do something here:
- we let the rod override the spring.
- */
- Real total_dist = 0.;
- for (int i = l; i < r; i++)
- total_dist += springs_[i].ideal_;
-
- if (total_dist < dist)
+ Real spring_dist = range_ideal_len (l, r);
+ if (spring_dist < dist)
for (int i = l; i < r; i++)
- springs_[i].ideal_ *= dist / total_dist;
+ {
+ if (spring_dist)
+ springs_[i].set_distance (springs_[i].distance () * dist / spring_dist);
+ else
+ springs_[i].set_distance (dist / (r - l));
+ }
return;
}
-
- Real d = range_ideal_len (l, r);
- Real block_stretch = dist - d;
-
- Real block_force = c * block_stretch;
force_ = max (force_, block_force);
-
for (int i = l; i < r; i++)
- springs_[i].block_force_ = max (block_force, springs_[i].block_force_);
+ springs_[i].set_blocking_force (max (block_force, springs_[i].blocking_force ()));
}
Real
{
Real d = 0.;
for (int i = l; i < r; i++)
- d += springs_[i].ideal_;
+ d += springs_[i].distance ();
return d;
}
Real
-Simple_spacer::range_stiffness (int l, int r) const
+Simple_spacer::range_stiffness (int l, int r, bool stretch) const
{
Real den = 0.0;
for (int i = l; i < r; i++)
- {
- if (springs_[i].is_active_)
- den += 1 * springs_[i].inverse_hooke_;
- }
+ den += stretch ? springs_[i].inverse_stretch_strength ()
+ : springs_[i].inverse_compress_strength ();
return 1 / den;
}
Real
-Simple_spacer::active_blocking_force () const
+Simple_spacer::configuration_length (Real force) const
{
- Real bf = -infinity_f;
+ Real l = 0.;
for (vsize i = 0; i < springs_.size (); i++)
- if (springs_[i].is_active_)
- bf = max (bf, springs_[i].block_force_);
- return bf;
-}
+ l += springs_[i].length (force);
-Real
-Simple_spacer::active_springs_stiffness () const
-{
- Real stiff = range_stiffness (0, springs_.size ());
- if (isinf (stiff))
- {
- /*
- all springs are inactive. Take the stiffness of the
- latest spring to block.
- */
-
- Real max_block_force = -infinity_f;
- int max_i = -1;
- for (vsize i = 0; i < springs_.size (); i++)
- {
- if (springs_[i].block_force_ > max_block_force)
- {
- max_i = i;
- max_block_force = springs_[i].block_force_;
- }
- }
-
- stiff = 1/springs_[max_i].inverse_hooke_;
- }
- return stiff;
+ return l;
}
void
-Simple_spacer::set_active_states ()
+Simple_spacer::solve (Real line_len, bool ragged)
{
- /* float comparison is safe, since force is only copied. */
- for (vsize i = 0; i < springs_.size (); i++)
- if (springs_[i].is_active_
- && springs_[i].block_force_ >= force_)
- {
- springs_[i].is_active_ = false;
- active_count_--;
- }
+ Real conf = configuration_length (force_);
+
+ ragged_ = ragged;
+ line_len_ = line_len;
+ if (conf < line_len_)
+ force_ = expand_line ();
+ else if (conf > line_len_)
+ force_ = compress_line ();
+
+ if (ragged && force_ < 0)
+ fits_ = false;
}
Real
-Simple_spacer::configuration_length () const
+Simple_spacer::expand_line ()
{
- Real l = 0.;
- for (vsize i = 0; i < springs_.size (); i++)
- l += springs_[i].length (force_);
+ double inv_hooke = 0;
+ double cur_len = configuration_length (force_);
- return l;
-}
+ fits_ = true;
+ for (vsize i=0; i < springs_.size (); i++)
+ inv_hooke += springs_[i].inverse_stretch_strength ();
-bool
-Simple_spacer::is_active () const
-{
- return active_count_;
+ if (inv_hooke == 0.0) /* avoid division by zero. If springs are infinitely stiff */
+ return 0.0; /* anyway, then it makes no difference what the force is */
+
+ assert (cur_len <= line_len_);
+ return (line_len_ - cur_len) / inv_hooke + force_;
}
-void
-Simple_spacer::my_solve_linelen ()
+Real
+Simple_spacer::compress_line ()
{
- while (is_active ())
+ double inv_hooke = 0;
+ double cur_len = configuration_length (force_);
+ double cur_force = force_;
+ bool compressed = false;
+
+ /* just because we are in compress_line () doesn't mean that the line
+ will actually be compressed (as in, a negative force) because
+ we start out with a stretched line. Here, we check whether we
+ will be compressed or stretched (so we know which spring constant to use) */
+ if (configuration_length (0.0) > line_len_)
{
- force_ = active_blocking_force ();
- Real conf = configuration_length ();
-
- if (conf < line_len_)
- {
- force_ += (line_len_ - conf) * active_springs_stiffness ();
- break;
- }
- else
- set_active_states ();
+ cur_force = 0.0;
+ cur_len = configuration_length (0.0);
+ compressed = true;
}
-}
-void
-Simple_spacer::my_solve_natural_len ()
-{
- Real line_len_force = 0.0;
+ fits_ = true;
+ for (vsize i=0; i < springs_.size (); i++)
+ inv_hooke += compressed
+ ? springs_[i].inverse_compress_strength ()
+ : springs_[i].inverse_stretch_strength ();
+
+ assert (line_len_ <= cur_len);
- while (is_active ())
+ vector<Spring> sorted_springs = springs_;
+ sort (sorted_springs.begin (), sorted_springs.end (), greater<Spring> ());
+
+ for (vsize i = 0; i < sorted_springs.size (); i++)
{
- force_ = max (active_blocking_force (), 0.0);
- Real conf = configuration_length ();
+ Spring sp = sorted_springs[i];
- if (conf < line_len_)
- {
- line_len_force = force_
- + (line_len_ - conf)
- * active_springs_stiffness ();
- }
+ if (sp.blocking_force () > cur_force)
+ continue;
- if (force_ < 1e-8) // ugh.,
+ if (isinf (sp.blocking_force ()))
break;
- set_active_states ();
+ double block_dist = (cur_force - sp.blocking_force ()) * inv_hooke;
+ if (cur_len - block_dist < line_len_)
+ {
+ cur_force += (line_len_ - cur_len) / inv_hooke;
+ cur_len = line_len_;
+
+ /*
+ Paranoia check.
+ */
+ assert (fabs (configuration_length (cur_force) - cur_len) < 1e-6);
+ return cur_force;
+ }
+
+ cur_len -= block_dist;
+ inv_hooke -= compressed ? sp.inverse_compress_strength () : sp.inverse_stretch_strength ();
+ cur_force = sp.blocking_force ();
}
- force_ = line_len_force;
+ fits_ = false;
+ return cur_force;
}
-/****************************************************************/
-
-Spring_description::Spring_description ()
+void
+Simple_spacer::add_spring (Spring const &sp)
{
- ideal_ = 0.0;
- inverse_hooke_ = 0.0;
- is_active_ = true;
- block_force_ = 0.0;
+ force_ = max (force_, sp.blocking_force ());
+ springs_.push_back (sp);
}
-bool
-Spring_description::is_sane () const
+vector<Real>
+Simple_spacer::spring_positions () const
{
- return (inverse_hooke_ >= 0)
- && ideal_ > 0
- && !isinf (ideal_) && !isnan (ideal_);
+ vector<Real> ret;
+ ret.push_back (0.);
+
+ for (vsize i = 0; i < springs_.size (); i++)
+ ret.push_back (ret.back () + springs_[i].length (ragged_ && force_ > 0 ? 0.0 : force_));
+ return ret;
}
Real
-Spring_description::length (Real f) const
+Simple_spacer::force_penalty (bool ragged) const
{
- if (!is_active_)
- f = block_force_;
- return ideal_ + f * inverse_hooke_;
-}
-/****************************************************************/
+ /* If we are ragged-right, we don't want to penalise according to the force,
+ but according to the amount of whitespace that is present after the end
+ of the line. */
+ if (ragged)
+ return max (0.0, line_len_ - configuration_length (0.0));
-/*
- TODO: should a add penalty for widely varying spring forces (caused
- by constraints, eg.
+ /* Use a convex compression penalty. */
+ Real f = force_;
+ return f - (f < 0 ? f*f*f*f*2 : 0);
+}
+/****************************************************************/
- . =====
- . | |
- .o|o|x ##x
- .
+struct Rod_description
+{
+ vsize r_;
+ Real dist_;
+
+ bool operator< (const Rod_description r)
+ {
+ return r_ < r.r_;
+ }
+
+ Rod_description ()
+ {
+ r_ = 0;
+ dist_ = 0;
+ }
+
+ Rod_description (vsize r, Real d)
+ {
+ r_ = r;
+ dist_ = d;
+ }
+};
+
+struct Column_description
+{
+ vector<Rod_description> rods_;
+ vector<Rod_description> end_rods_; /* use these if they end at the last column of the line */
+ Spring spring_;
+ Spring end_spring_;
+
+ SCM break_permission_;
+ Interval keep_inside_line_;
+
+ Column_description ()
+ {
+ break_permission_ = SCM_EOL;
+ }
+};
+
+static bool
+is_loose (Grob *g)
+{
+ return (scm_is_pair (g->get_object ("between-cols")));
+}
- The ## forces the notes apart; we shouldn't allow the O's to touch
- this closely.
-*/
-void
-Simple_spacer_wrapper::solve (Column_x_positions *positions, bool ragged)
+static Grob*
+maybe_find_prebroken_piece (Grob *g, Direction d)
{
- if (ragged)
- spacer_->my_solve_natural_len ();
- else
- spacer_->my_solve_linelen ();
+ Grob *ret = dynamic_cast<Item*> (g)->find_prebroken_piece (d);
+ if (ret)
+ return ret;
+ return g;
+}
- positions->force_ = spacer_->force_;
+static Grob*
+next_spaceable_column (vector<Grob*> const &list, vsize starting)
+{
+ for (vsize i = starting+1; i < list.size (); i++)
+ if (!is_loose (list[i]))
+ return list[i];
+ return 0;
+}
- /*
- We used to have a penalty for compression, no matter what, but that
- fucked up wtk1-fugue2 (taking 3 full pages.)
- */
- positions->config_.push_back (spacer_->indent_);
- for (vsize i = 0; i < spacer_->springs_.size (); i++)
- {
- Real l = spacer_->springs_[i].length ((ragged) ? 0.0 : spacer_->force_);
- positions->config_.push_back (positions->config_.back () + l);
- /*
- we have l>= 0 here, up to rounding errors
- */
- }
+static Column_description
+get_column_description (vector<Grob*> const &cols, vsize col_index, bool line_starter)
+{
+ Grob *col = cols[col_index];
+ if (line_starter)
+ col = maybe_find_prebroken_piece (col, RIGHT);
- /*
- For raggedright, we must have a measure of music density: this is
- to prevent lots of short lines (which all have force = 0).
- */
- if (ragged)
- {
- positions->satisfies_constraints_
- = positions->config_.back () < spacer_->line_len_;
- }
- else
- positions->satisfies_constraints_ = spacer_->is_active ();
+ Column_description description;
+ Grob *next_col = next_spaceable_column (cols, col_index);
+ if (next_col)
+ description.spring_ = Spaceable_grob::get_spring (col, next_col);
- positions->cols_ = spaced_cols_;
- positions->loose_cols_ = loose_cols_;
+ Grob *end_col = dynamic_cast<Item*> (cols[col_index+1])->find_prebroken_piece (LEFT);
+ if (end_col)
+ description.end_spring_ = Spaceable_grob::get_spring (col, end_col);
- /*
- Check if breaking constraints are met.
- */
- bool break_satisfy = true;
- int sz = positions->cols_.size ();
- for (int i = sz; i--;)
+ for (SCM s = Spaceable_grob::get_minimum_distances (col);
+ scm_is_pair (s); s = scm_cdr (s))
{
- SCM p = positions->cols_[i]->get_property ("penalty");
- if (scm_is_number (p))
+ Grob *other = unsmob_grob (scm_caar (s));
+ vsize j = binary_search (cols, other, Paper_column::less_than, col_index);
+ if (j != VPOS)
{
- if (scm_to_double (p) < -9999)
- break_satisfy = break_satisfy && (i == 0 || i == sz -1);
- if (scm_to_double (p) > 9999)
- break_satisfy = break_satisfy && ! (i == 0 || i == sz -1);
+ if (cols[j] == other)
+ description.rods_.push_back (Rod_description (j, scm_to_double (scm_cdar (s))));
+ else /* it must end at the LEFT prebroken_piece */
+ description.end_rods_.push_back (Rod_description (j, scm_to_double (scm_cdar (s))));
}
}
+
+ if (!line_starter && to_boolean (col->get_property ("keep-inside-line")))
+ description.keep_inside_line_ = col->extent (col, X_AXIS);
- positions->satisfies_constraints_
- = positions->satisfies_constraints_ && break_satisfy;
+ description.break_permission_ = col->get_property ("line-break-permission");
+ return description;
}
-void
-Simple_spacer::add_spring (Real ideal, Real inverse_hooke)
+vector<Real>
+get_line_forces (vector<Grob*> const &columns,
+ Real line_len, Real indent, bool ragged)
{
- Spring_description desc;
-
- desc.ideal_ = ideal;
- desc.inverse_hooke_ = inverse_hooke;
- if (!desc.is_sane ())
+ vector<vsize> breaks;
+ vector<Real> force;
+ vector<Grob*> non_loose;
+ vector<Column_description> cols;
+ SCM force_break = ly_symbol2scm ("force");
+
+ for (vsize i = 0; i < columns.size (); i++)
+ if (!is_loose (columns[i]) || Paper_column::is_breakable (columns[i]))
+ non_loose.push_back (columns[i]);
+
+ breaks.clear ();
+ breaks.push_back (0);
+ cols.push_back (Column_description ());
+ for (vsize i = 1; i + 1 < non_loose.size (); i++)
{
- programming_error ("insane spring found, setting to unit");
+ if (Paper_column::is_breakable (non_loose[i]))
+ breaks.push_back (cols.size ());
- desc.inverse_hooke_ = 1.0;
- desc.ideal_ = 1.0;
+ cols.push_back (get_column_description (non_loose, i, false));
}
+ breaks.push_back (cols.size ());
+ force.resize (breaks.size () * breaks.size (), infinity_f);
- if (!inverse_hooke)
- desc.is_active_ = false;
- else
+ for (vsize b = 0; b + 1 < breaks.size (); b++)
{
- /*
- desc.is_active_ ?
- */
- desc.block_force_ = -desc.ideal_ / desc.inverse_hooke_;
- // block at distance 0
+ cols[breaks[b]] = get_column_description (non_loose, breaks[b], true);
+ vsize st = breaks[b];
- active_count_++;
- }
- springs_.push_back (desc);
-}
+ for (vsize c = b+1; c < breaks.size (); c++)
+ {
+ vsize end = breaks[c];
+ Simple_spacer spacer;
-static int
-compare_paper_column_rank (Grob *const &a,
- Grob *const &b)
-{
- return Paper_column::get_rank (a) - Paper_column::get_rank (b);
+ for (vsize i = breaks[b]; i < end - 1; i++)
+ spacer.add_spring (cols[i].spring_);
+ spacer.add_spring (cols[end-1].end_spring_);
+
+
+ for (vsize i = breaks[b]; i < end; i++)
+ {
+ for (vsize r = 0; r < cols[i].rods_.size (); r++)
+ if (cols[i].rods_[r].r_ < end)
+ spacer.add_rod (i - st, cols[i].rods_[r].r_ - st, cols[i].rods_[r].dist_);
+ for (vsize r = 0; r < cols[i].end_rods_.size (); r++)
+ if (cols[i].end_rods_[r].r_ == end)
+ spacer.add_rod (i - st, end - st, cols[i].end_rods_[r].dist_);
+ if (!cols[i].keep_inside_line_.is_empty ())
+ {
+ spacer.add_rod (i - st, end - st, cols[i].keep_inside_line_[RIGHT]);
+ spacer.add_rod (0, i - st, -cols[i].keep_inside_line_[LEFT]);
+ }
+ }
+ spacer.solve ((b == 0) ? line_len - indent : line_len, ragged);
+ force[b * breaks.size () + c] = spacer.force_penalty (ragged);
+
+ if (!spacer.fits ())
+ {
+ if (c == b + 1)
+ force[b * breaks.size () + c] = -200000;
+ else
+ force[b * breaks.size () + c] = infinity_f;
+ break;
+ }
+ if (end < cols.size () && cols[end].break_permission_ == force_break)
+ break;
+ }
+ }
+ return force;
}
-void
-Simple_spacer_wrapper::add_columns (Link_array<Grob> const &icols)
+Column_x_positions
+get_line_configuration (vector<Grob*> const &columns,
+ Real line_len,
+ Real indent,
+ bool ragged)
{
- Link_array<Grob> cols (icols);
- cols.clear ();
+ vector<Column_description> cols;
+ Simple_spacer spacer;
+ Column_x_positions ret;
- for (vsize i = 0; i < icols.size (); i++)
- if (scm_is_pair (icols[i]->get_object ("between-cols")))
- loose_cols_.push_back (icols[i]);
- else
- cols.push_back (icols[i]);
+ ret.cols_.push_back (dynamic_cast<Item*> (columns[0])->find_prebroken_piece (RIGHT));
+ for (vsize i = 1; i + 1 < columns.size (); i++)
+ {
+ if (is_loose (columns[i]))
+ ret.loose_cols_.push_back (columns[i]);
+ else
+ ret.cols_.push_back (columns[i]);
+ }
+ ret.cols_.push_back (dynamic_cast<Item*> (columns.back ())->find_prebroken_piece (LEFT));
- spaced_cols_ = cols;
- for (vsize i = 0; i < cols.size () - 1; i++)
+ /* since we've already put our line-ending column in the column list, we can ignore
+ the end_XXX_ fields of our column_description */
+ for (vsize i = 0; i + 1 < ret.cols_.size (); i++)
{
- Spring_smob *spring = 0;
+ cols.push_back (get_column_description (ret.cols_, i, i == 0));
+ spacer.add_spring (cols[i].spring_);
+ }
+ for (vsize i = 0; i < cols.size (); i++)
+ {
+ for (vsize r = 0; r < cols[i].rods_.size (); r++)
+ spacer.add_rod (i, cols[i].rods_[r].r_, cols[i].rods_[r].dist_);
- for (SCM s = cols[i]->get_object ("ideal-distances");
- !spring && scm_is_pair (s);
- s = scm_cdr (s))
+ if (!cols[i].keep_inside_line_.is_empty ())
{
- Spring_smob *sp = unsmob_spring (scm_car (s));
-
- if (sp->other_ == cols[i + 1])
- spring = sp;
+ spacer.add_rod (i, cols.size (), cols[i].keep_inside_line_[RIGHT]);
+ spacer.add_rod (0, i, -cols[i].keep_inside_line_[LEFT]);
}
+ }
- if (!spring)
- programming_error (_f ("No spring between column %d and next one",
- Paper_column::get_rank (cols[i])));
+ spacer.solve (line_len, ragged);
+ ret.force_ = spacer.force_penalty (ragged);
- Real ideal = (spring) ? spring->distance_ : spacer_->default_space_;
- Real inverse_hooke = (spring) ? spring->inverse_strength_ : 1.0;
+ ret.config_ = spacer.spring_positions ();
+ for (vsize i = 0; i < ret.config_.size (); i++)
+ ret.config_[i] += indent;
- spacer_->add_spring (ideal, inverse_hooke);
- }
+ ret.satisfies_constraints_ = spacer.fits ();
- for (vsize i = 0; i < cols.size () - 1; i++)
+ /*
+ Check if breaking constraints are met.
+ */
+ for (vsize i = 1; i + 1 < ret.cols_.size (); i++)
{
- for (SCM s = Spaceable_grob::get_minimum_distances (cols[i]);
- scm_is_pair (s); s = scm_cdr (s))
- {
- Grob *other = unsmob_grob (scm_caar (s));
- int j = binsearch_links (cols, other, &compare_paper_column_rank);
- if (j >= 0 && cols[j] == other)
- spacer_->add_rod (i, j, scm_to_double (scm_cdar (s)));
- }
-
- if (i
- && to_boolean (cols[i]->get_property ("keep-inside-line")))
- {
- Interval e = cols[i]->extent (cols[i], X_AXIS);
- if (!e.is_empty ())
- {
- spacer_->add_rod (i, cols.size () - 1, e[RIGHT]);
- spacer_->add_rod (0, i, e[LEFT]);
- }
- }
+ SCM p = ret.cols_[i]->get_property ("line-break-permission");
+ if (p == ly_symbol2scm ("force"))
+ ret.satisfies_constraints_ = false;
}
-}
-
-Simple_spacer_wrapper::Simple_spacer_wrapper ()
-{
- spacer_ = new Simple_spacer ();
-}
-Simple_spacer_wrapper::~Simple_spacer_wrapper ()
-{
- delete spacer_;
+ return ret;
}
-Simple_spacer_wrapper::Simple_spacer_wrapper (Simple_spacer_wrapper const &)
-{
-}