source file of the GNU LilyPond music typesetter
- (c) 2006--2007 Joe Neeman <joeneeman@gmail.com>
+ (c) 2006--2008 Joe Neeman <joeneeman@gmail.com>
*/
#include "constrained-breaking.hh"
#include "warn.hh"
/*
- We use the following optimal substructure. Let W(A) be our weight function.
+ We use the following optimal substructure. Let W (A) be our weight function.
- Let A_{k,n} = (a_{k,n,1}, ... a_{k,n,k}) be the optimal set of line breaks
- for k systems and n potential breakpoints. a_{k,n,k} = n (it is the end of
+ Let A_{k, n} = (a_{k, n,1}, ... a_{k, n, k}) be the optimal set of line breaks
+ for k systems and n potential breakpoints. a_{k, n, k} = n (it is the end of
the piece)
Then A_{k+1, m} is contructed from
- min_ {k < j < m} ( W(A_{k,j} :: m) )
+ min_ {k < j < m} ( W (A_{k, j} :: m) )
where by A::m we denote appending m to the list A
Indices in the code:
The above algorithm makes it easy to end at a point before the end of the
- score (just find A_{k,m} for some m < breaks_.size () - 1). However, we must
+ score (just find A_{k, m} for some m < breaks_.size () - 1). However, we must
add information for starting at a point after the beginning. One constructor
allows the specification of a list of starting columns, start_. We then have
start_.size () different solution arrays. state_[i] is the array for the
. . . .
. . . .
where the X's mark invalid solutions (can't have more systems than
- breakpoints). Note that each value is of the form a_{x,n,x}. This is because
- a breakpoint of the form a_{x,n,x-1} will also be called a_{x-1,m,x-1} for
+ breakpoints). Note that each value is of the form a_{x, n, x}. This is because
+ a breakpoint of the form a_{x, n, x-1} will also be called a_{x-1, m, x-1} for
some m < n. Each cell in the array stores the value of its m (ie. the
ending breakpoint of the previous line) as "prev_".
- For finding A_{sys, brk}, let "me" be the (sys_count,brk) cell in our
+ For finding A_{sys, brk}, let "me" be the (sys_count, brk) cell in our
solution array (state_[start][sys * rank + brk]).
Then A_{sys, brk} = A_{sys - 1, me.prev_} :: me
return found_something;
}
+
Column_x_positions
Constrained_breaking::space_line (vsize i, vsize j)
{
Column_x_positions col;
vector<Grob*> line (all_.begin () + breaks_[i],
- all_.begin() + breaks_[j] + 1);
+ all_.begin () + breaks_[j] + 1);
Interval line_dims = line_dimensions_int (pscore_->layout (), i);
bool last = j == breaks_.size () - 1;
bool ragged = ragged_right || (last && ragged_last);
+ /* As a special case, if there is only one line in the score and ragged-right
+ hasn't been specifically forbidden and the line is stretched, use
+ ragged spacing. */
+ if (last && i == 0
+ && lines_.at (i, j).force_ >= 0
+ && !scm_is_bool (pscore_->layout ()->c_variable ("ragged-right"))
+ && !scm_is_bool (pscore_->layout ()->c_variable ("ragged-last")))
+ ragged = true;
+
return get_line_configuration (line, line_dims[RIGHT] - line_dims[LEFT], line_dims[LEFT], ragged);
}
vector<Column_x_positions>
Constrained_breaking::best_solution (vsize start, vsize end)
{
- vsize min_systems = min_system_count (start, end);
+ vsize min_systems = min_system_count (start, end);
vsize max_systems = max_system_count (start, end);
Real best_demerits = infinity_f;
vector<Column_x_positions> best_so_far;
initialize ();
}
+static SCM
+min_permission (SCM perm1, SCM perm2)
+{
+ if (perm1 == ly_symbol2scm ("force"))
+ return perm2;
+ if (perm1 == ly_symbol2scm ("allow")
+ && perm2 != ly_symbol2scm ("force"))
+ return perm2;
+ return SCM_EOL;
+}
+
/* find the forces for all possible lines and cache ragged_ and ragged_right_ */
void
Constrained_breaking::initialize ()
ragged_right_);
for (vsize i = 0; i + 1 < breaks_.size (); i++)
{
- Real max_ext = 0;
for (vsize j = i + 1; j < breaks_.size (); j++)
{
int start = Paper_column::get_rank (all_[breaks_[i]]);
line.force_ = forces[i*breaks_.size () + j];
if (ragged && last && !isinf (line.force_))
- line.force_ = (line.force_ < 0) ? infinity_f : 0;
+ line.force_ = (line.force_ < 0 && j > i + 1) ? infinity_f : 0;
if (isinf (line.force_))
break;
line.break_permission_ = c->get_property ("line-break-permission");
line.page_permission_ = c->get_property ("page-break-permission");
line.turn_permission_ = c->get_property ("page-turn-permission");
-
- max_ext = max (max_ext, extent.length ());
- line.extent_ = extent;
+
+ /* turn permission should always be stricter than page permission
+ and page permission should always be stricter than line permission */
+ line.page_permission_ = min_permission (line.break_permission_,
+ line.page_permission_);
+ line.turn_permission_ = min_permission (line.page_permission_,
+ line.turn_permission_);
+
+ line.extent_ = (extent.is_empty ()
+ || isnan (extent[LEFT])
+ || isnan (extent[RIGHT]))
+ ? Interval (0, 0) : extent;
line.padding_ = padding;
line.space_ = space;
line.inverse_hooke_ = extent.length () + space;