source file of the GNU LilyPond music typesetter
- (c) 1999--2006 Han-Wen Nienhuys <hanwen@xs4all.nl>
+ (c) 1999--2009 Han-Wen Nienhuys <hanwen@xs4all.nl>
TODO:
- add support for different stretch/shrink constants?
Real
Simple_spacer::rod_force (int l, int r, Real dist)
{
- Real c = range_stiffness (l, r);
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;
}
Real spring_dist = range_ideal_len (l, r);
if (spring_dist < dist)
for (int i = l; i < r; i++)
- springs_[i].ideal_ *= dist / spring_dist;
+ {
+ if (spring_dist)
+ springs_[i].set_distance (springs_[i].distance () * dist / spring_dist);
+ else
+ springs_[i].set_distance (dist / (r - l));
+ }
return;
}
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++)
- den += springs_[i].inverse_hooke_;
+ den += stretch ? springs_[i].inverse_stretch_strength ()
+ : springs_[i].inverse_compress_strength ();
return 1 / den;
}
fits_ = true;
for (vsize i=0; i < springs_.size (); i++)
- inv_hooke += springs_[i].inverse_hooke_;
+ inv_hooke += springs_[i].inverse_stretch_strength ();
+
+ 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_;
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_)
+ {
+ cur_force = 0.0;
+ cur_len = configuration_length (0.0);
+ compressed = true;
+ }
fits_ = true;
for (vsize i=0; i < springs_.size (); i++)
- inv_hooke += springs_[i].inverse_hooke_;
+ inv_hooke += compressed
+ ? springs_[i].inverse_compress_strength ()
+ : springs_[i].inverse_stretch_strength ();
assert (line_len_ <= cur_len);
- vector<Spring_description> sorted_springs = springs_;
- sort (sorted_springs.begin (), sorted_springs.end (), greater<Spring_description> ());
+ vector<Spring> sorted_springs = springs_;
+ sort (sorted_springs.begin (), sorted_springs.end (), greater<Spring> ());
+
for (vsize i = 0; i < sorted_springs.size (); i++)
{
- Spring_description sp = sorted_springs[i];
+ Spring sp = sorted_springs[i];
- assert (sp.block_force_ <= cur_force);
- if (isinf (sp.block_force_))
+ assert (sp.blocking_force () <= cur_force);
+ if (isinf (sp.blocking_force ()))
break;
- double block_dist = (cur_force - sp.block_force_) * inv_hooke;
+ 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_;
+ cur_force += (line_len_ - cur_len) / inv_hooke;
+ cur_len = line_len_;
- /*
- Paranoia check.
+ /*
+ Paranoia check.
*/
- assert (fabs (configuration_length (cur_force) - cur_len) < 1e-6);
- return cur_force;
+ assert (fabs (configuration_length (cur_force) - cur_len) < 1e-6);
+ return cur_force;
}
cur_len -= block_dist;
- inv_hooke -= sp.inverse_hooke_;
- cur_force = sp.block_force_;
+ inv_hooke -= sp.inverse_compress_strength ();
+ cur_force = sp.blocking_force ();
}
fits_ = false;
}
void
-Simple_spacer::add_spring (Real ideal, Real inverse_hooke)
+Simple_spacer::add_spring (Spring const &sp)
{
- Spring_description description;
-
- description.ideal_ = ideal;
- description.inverse_hooke_ = inverse_hooke;
- if (!description.is_sane ())
- {
- programming_error ("insane spring found, setting to unit");
-
- description.inverse_hooke_ = 1.0;
- description.ideal_ = 1.0;
- }
-
- description.block_force_ = -description.ideal_ / description.inverse_hooke_;
- // block at distance 0
-
- springs_.push_back (description);
+ force_ = max (force_, sp.blocking_force ());
+ springs_.push_back (sp);
}
vector<Real>
return ret;
}
-/****************************************************************/
-
-Spring_description::Spring_description ()
-{
- ideal_ = 0.0;
- inverse_hooke_ = 0.0;
- block_force_ = 0.0;
-}
-
-bool
-Spring_description::is_sane () const
-{
- return (inverse_hooke_ >= 0)
- && ideal_ > 0
- && !isinf (ideal_) && !isnan (ideal_)
- && (inverse_hooke_ == 0.0 || fabs (inverse_hooke_) > 1e-8)
- ;
-}
-
Real
-Spring_description::length (Real f) const
+Simple_spacer::force_penalty (bool ragged) const
{
- return ideal_ + max (f, block_force_) * 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));
+
+ /* Use a convex compression penalty. */
+ Real f = force_;
+ return f - (f < 0 ? f*f*f*f*2 : 0);
}
/****************************************************************/
-/*
- TODO: should a add penalty for widely varying spring forces (caused
- by constraints, eg.
-
-
- . =====
- . | |
- .o|o|x ##x
- .
-
- The ## forces the notes apart; we shouldn't allow the O's to touch
- this closely.
-*/
-
struct Rod_description
{
vsize r_;
{
vector<Rod_description> rods_;
vector<Rod_description> end_rods_; /* use these if they end at the last column of the line */
- Real ideal_;
- Real inverse_hooke_;
- Real end_ideal_;
- Real end_inverse_hooke_;
+ Spring spring_;
+ Spring end_spring_;
+
SCM break_permission_;
Interval keep_inside_line_;
Column_description ()
{
- ideal_ = 0;
- inverse_hooke_ = 0;
- end_ideal_ = 0;
- end_inverse_hooke_ = 0;
break_permission_ = SCM_EOL;
}
};
return 0;
}
-static void
-get_column_spring (Grob *this_col, Grob *next_col, Real *ideal, Real *inv_hooke)
-{
- Spring_smob *spring = 0;
-
- for (SCM s = this_col->get_object ("ideal-distances");
- !spring && scm_is_pair (s);
- s = scm_cdr (s))
- {
- Spring_smob *sp = unsmob_spring (scm_car (s));
-
- if (sp->other_ == next_col)
- spring = sp;
- }
-
- if (!spring)
- programming_error (_f ("No spring between column %d and next one",
- Paper_column::get_rank (this_col)));
-
- *ideal = (spring) ? spring->distance_ : 5.0;
- *inv_hooke = (spring) ? spring->inverse_strength_ : 1.0;
-}
-
static Column_description
get_column_description (vector<Grob*> const &cols, vsize col_index, bool line_starter)
{
Column_description description;
Grob *next_col = next_spaceable_column (cols, col_index);
if (next_col)
- get_column_spring (col, next_col, &description.ideal_, &description.inverse_hooke_);
+ description.spring_ = Spaceable_grob::get_spring (col, next_col);
+
Grob *end_col = dynamic_cast<Item*> (cols[col_index+1])->find_prebroken_piece (LEFT);
if (end_col)
- get_column_spring (col, end_col, &description.end_ideal_, &description.end_inverse_hooke_);
+ description.end_spring_ = Spaceable_grob::get_spring (col, end_col);
for (SCM s = Spaceable_grob::get_minimum_distances (col);
scm_is_pair (s); s = scm_cdr (s))
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);
+
description.break_permission_ = col->get_property ("line-break-permission");
return description;
}
breaks.clear ();
breaks.push_back (0);
cols.push_back (Column_description ());
- for (vsize i = 1; i < non_loose.size () - 1; i++)
+ for (vsize i = 1; i + 1 < non_loose.size (); i++)
{
if (Paper_column::is_breakable (non_loose[i]))
breaks.push_back (cols.size ());
breaks.push_back (cols.size ());
force.resize (breaks.size () * breaks.size (), infinity_f);
- for (vsize b = 0; b < breaks.size () - 1; b++)
+ for (vsize b = 0; b + 1 < breaks.size (); b++)
{
cols[breaks[b]] = get_column_description (non_loose, breaks[b], true);
vsize st = breaks[b];
Simple_spacer spacer;
for (vsize i = breaks[b]; i < end - 1; i++)
- spacer.add_spring (cols[i].ideal_, cols[i].inverse_hooke_);
- spacer.add_spring (cols[end-1].end_ideal_, cols[end-1].end_inverse_hooke_);
+ spacer.add_spring (cols[i].spring_);
+ spacer.add_spring (cols[end-1].end_spring_);
for (vsize i = breaks[b]; i < end; i++)
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.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);
- /* add a (convex) penalty for compression. We do this _only_ in get_line_forces,
- not get_line_configuration. This is temporary, for backwards compatibility;
- the old line/page-breaking stuff ignores page breaks when it calculates line
- breaks, so compression penalties can result in scores (eg. wtk-fugue) blowing
- up to too many pages. */
- Real f = spacer.force ();
- force[b * breaks.size () + c] = f - (f < 0 ? f*f*f*f*4 : 0);
-
- if (end < cols.size () && cols[end].break_permission_ == force_break)
- break;
if (!spacer.fits ())
{
if (c == b + 1)
force[b * breaks.size () + c] = infinity_f;
break;
}
+ if (end < cols.size () && cols[end].break_permission_ == force_break)
+ break;
}
}
return force;
Column_x_positions ret;
ret.cols_.push_back (dynamic_cast<Item*> (columns[0])->find_prebroken_piece (RIGHT));
- for (vsize i = 1; i < columns.size () - 1; i++)
+ for (vsize i = 1; i + 1 < columns.size (); i++)
{
if (is_loose (columns[i]))
ret.loose_cols_.push_back (columns[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 < ret.cols_.size () - 1; i++)
+ for (vsize i = 0; i + 1 < ret.cols_.size (); i++)
{
cols.push_back (get_column_description (ret.cols_, i, i == 0));
- spacer.add_spring (cols[i].ideal_, cols[i].inverse_hooke_);
+ spacer.add_spring (cols[i].spring_);
}
for (vsize i = 0; i < cols.size (); i++)
{
if (!cols[i].keep_inside_line_.is_empty ())
{
spacer.add_rod (i, cols.size (), cols[i].keep_inside_line_[RIGHT]);
- spacer.add_rod (0, i, cols[i].keep_inside_line_[LEFT]);
+ spacer.add_rod (0, i, -cols[i].keep_inside_line_[LEFT]);
}
}
spacer.solve (line_len, ragged);
- ret.force_ = spacer.force ();
+ ret.force_ = spacer.force_penalty (ragged);
- /*
- We used to have a penalty for compression, no matter what, but that
- fucked up wtk1-fugue2 (taking 3 full pages.)
- */
ret.config_ = spacer.spring_positions ();
for (vsize i = 0; i < ret.config_.size (); i++)
ret.config_[i] += indent;
/*
Check if breaking constraints are met.
*/
- for (vsize i = 1; i < ret.cols_.size () - 1; i++)
+ for (vsize i = 1; i + 1 < ret.cols_.size (); i++)
{
SCM p = ret.cols_[i]->get_property ("line-break-permission");
if (p == ly_symbol2scm ("force"))