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 "linespace.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_.cols,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 void
  35 Break_algorithm::generate_spacing_problem(Line_of_cols curline, Spacing_problem & sp)const
  36 {
  37     sp.add_column(curline[0], true, 0.0);
  38     for (int i=1; i< curline.size()-1; i++)
  39        sp.add_column(curline[i]);
  40
  41     if ( linelength > 0)
  42         sp.add_column(curline.top(), true, linelength);
  43     else
  44         sp.add_column(curline.top());
  45 }
  46
  47 Col_hpositions
  48 Break_algorithm::stupid_solution(Line_of_cols curline)const
  49 {
  50     Spacing_problem sp;
  51     generate_spacing_problem(curline, sp);
  52    Col_hpositions colhpos;
  53    colhpos.cols = curline;
  54    colhpos.energy = INFTY;
  55    colhpos.ugh_b_ = true;
  56    colhpos.config = sp.try_initial_solution();
  57    return colhpos;
  58 }
  59
  60 /// construct an appropriate Spacing_problem and solve it.
  61 Col_hpositions
  62 Break_algorithm::solve_line(Line_of_cols curline) const
  63 {
  64    Spacing_problem sp;
  65    generate_spacing_problem(curline, sp);
  66
  67    // misschien  moeven uit Spacing_problem?
  68    for (iter_top(pscore_.suz,i); i.ok(); i++) {
  69        sp.add_ideal(i);
  70    }
  71    sp.prepare();
  72
  73    Array<Real> the_sol=sp.solve();
  74    Col_hpositions col_hpos;
  75    col_hpos.cols = curline;
  76    col_hpos.energy = the_sol.pop();
  77    col_hpos.config = the_sol;
  78    col_hpos.error_col_l_arr_ = sp.error_pcol_l_arr();
  79    col_hpos.OK();
  80    return col_hpos;
  81 }
  82
  83 Break_algorithm::Break_algorithm(PScore&s)
  84     :pscore_(s)
  85 {
  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_.cols.size())
 105         error("Score does not have any columns");
 106 #ifndef NDEBUG
 107     iter_top(pscore_.cols,start);
 108     PCursor<PCol *> end (pscore_.cols.bottom());
 109
 110     assert(start->breakable_b());
 111     assert(end->breakable_b());
 112 #endif
 113 }
 114
 115 Array<Col_hpositions>
 116 Break_algorithm::solve()const
 117 {
 118
 119     return do_solve();
 120 }
 121