lily/include/break.hh

   1 /*
   2   break.hh -- declare  Break_algorithm
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1996,  1997--1998 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7 */
   8
   9
  10 #ifndef BREAK_HH
  11 #define BREAK_HH
  12 #include "array.hh"
  13 #include "interval.hh"
  14 #include "lily-proto.hh"
  15 #include "colhpos.hh"
  16
  17 /**
  18   Statistics for the number of columns calced.
  19  */
  20 struct Col_stats
  21 {
  22   int count_i_;
  23   int cols_i_;
  24
  25   Col_stats();
  26   void add (Line_of_cols const&l);
  27   String str() const;
  28 };
  29
  30 /** Class representation of an algorithm which decides where to put
  31   the column, and where to break lines.
  32
  33   TODO:  A "parindent", caching of breakpoints
  34
  35   */
  36 class Break_algorithm {
  37 protected:
  38
  39   Paper_score *pscore_l_;
  40   Real linelength;
  41
  42   /// search all pcols which are breakable.
  43   Line_of_cols find_breaks() const;
  44
  45   Line_of_cols all_cols() const;
  46   Array<int> find_break_indices() const;
  47
  48
  49   /// helper: solve for the columns in #curline#.
  50   void solve_line (Column_x_positions*) const;
  51
  52   /// helper: approximate the energyv
  53   void approximate_solve_line (Column_x_positions*) const;
  54
  55   /// does curline fit on the paper?
  56   bool feasible (Line_of_cols) const;
  57
  58
  59   Line_spacer* generate_spacing_problem (Line_of_cols, Interval) const;
  60
  61   virtual Array<Column_x_positions> do_solve() const=0;
  62   virtual void do_set_pscore();
  63
  64 public:
  65   Col_stats approx_stats_;
  66   Col_stats exact_stats_;
  67
  68   Line_spacer* (*get_line_spacer)();
  69
  70   Break_algorithm();
  71   void set_pscore (Paper_score*);
  72
  73   /// check if the spacing/breaking problem is well-stated
  74   void problem_OK() const;
  75   void OK() const;
  76   Array<Column_x_positions> solve() const;
  77 };
  78
  79 #endif // BREAK_HH
  80