lily/break.cc

   1 /*
   2   break.cc -- implement Break_algorithm
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1996, 1997 Han-Wen Nienhuys <hanwen@stack.nl>
   7 */
   8
   9
  10 #include "break.hh"
  11 #include "paper-def.hh"
  12 #include "line-spacer.hh"
  13 #include "debug.hh"
  14 #include "scoreline.hh"
  15 #include "p-score.hh"
  16 #include "p-col.hh"
  17
  18 ///  return all breakable columns
  19 Line_of_cols
  20 Break_algorithm::find_breaks() const
  21 {
  22     Line_of_cols retval;
  23     for (iter_top(pscore_l_->col_p_list_,c); c.ok(); c++) {
  24         if (c->breakable_b())
  25             retval.push(c);
  26     }
  27     if ( linelength <=0)
  28         while ( retval.size() >2)
  29             retval.del(1);
  30
  31     return retval;
  32 }
  33
  34 Line_spacer*
  35 Break_algorithm::generate_spacing_problem(Line_of_cols curline)const
  36 {
  37     Line_spacer * sp= (*get_line_spacer)();
  38     sp->paper_l_ = pscore_l_->paper_l_;
  39     sp->add_column(curline[0], true, 0.0);
  40     for (int i=1; i< curline.size()-1; i++)
  41         sp->add_column(curline[i]);
  42
  43     if ( linelength > 0)
  44         sp->add_column(curline.top(), true, linelength);
  45     else
  46         sp->add_column(curline.top());
  47     return sp;
  48 }
  49
  50 Col_hpositions
  51 Break_algorithm::stupid_solution(Line_of_cols curline)const
  52 {
  53     Line_spacer *sp =generate_spacing_problem(curline);
  54     Col_hpositions colhpos;
  55     colhpos.cols = curline;
  56     colhpos.energy = INFTY_f;
  57     colhpos.ugh_b_ = true;
  58     colhpos.config = sp->default_solution();
  59     delete sp;
  60     return colhpos;
  61 }
  62
  63 /// construct an appropriate Spacing_problem and solve it.
  64 Col_hpositions
  65 Break_algorithm::solve_line(Line_of_cols curline) const
  66 {
  67     Line_spacer *sp = generate_spacing_problem(curline);
  68     sp->prepare();
  69
  70     Array<Real> the_sol=sp->solve();
  71     Col_hpositions col_hpos;
  72     col_hpos.cols = curline;
  73     col_hpos.energy = the_sol.pop();
  74     col_hpos.config = the_sol;
  75     col_hpos.error_col_l_arr_ = sp->error_pcol_l_arr();
  76     col_hpos.OK();
  77     delete sp;
  78
  79     return col_hpos;
  80 }
  81
  82 Break_algorithm::Break_algorithm(PScore&s)
  83 {
  84     pscore_l_ = &s;
  85     get_line_spacer =0;
  86     linelength = s.paper_l_->linewidth_f();
  87 }
  88
  89 bool
  90 Break_algorithm::feasible(Line_of_cols curline) const
  91 {
  92     if (linelength <=  0)
  93         return true;
  94
  95     Real l =0;
  96     for (int i=0; i < curline.size(); i++)
  97         l +=curline[i]->width().length();
  98     return l < linelength;
  99 }
 100
 101 void
 102 Break_algorithm::problem_OK() const
 103 {
 104     if (!pscore_l_->col_p_list_.size())
 105         error("Score does not have any columns");
 106     OK();
 107 }
 108
 109 void
 110 Break_algorithm::OK()const
 111 {
 112 #ifndef NDEBUG
 113     iter_top(pscore_l_->col_p_list_,start);
 114     PCursor<PCol *> end (pscore_l_->col_p_list_.bottom());
 115
 116     assert(start->breakable_b());
 117     assert(end->breakable_b());
 118 #endif
 119 }
 120
 121 Array<Col_hpositions>
 122 Break_algorithm::solve()const
 123 {
 124     return do_solve();
 125 }
 126