lily/spaceable-grob.cc

   1 /*
   2   spaceable-grob.cc -- implement Spaceable_grob
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2000--2009 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7 */
   8
   9 #include "spaceable-grob.hh"
  10
  11 #include <cstdio>
  12
  13 #include "warn.hh"
  14 #include "spring.hh"
  15 #include "pointer-group-interface.hh"
  16 #include "grob.hh"
  17 #include "paper-column.hh"
  18 #include "international.hh"
  19
  20 SCM
  21 Spaceable_grob::get_minimum_distances (Grob *me)
  22 {
  23   return me->get_object ("minimum-distances");
  24 }
  25
  26 /*todo: merge code of spring & rod?
  27  */
  28 void
  29 Spaceable_grob::add_rod (Grob *me, Grob *p, Real d)
  30 {
  31   //  printf ("rod %lf\n", d);
  32   if (d < 0)
  33     return;
  34
  35   if (isinf (d))
  36     programming_error ("infinite rod");
  37
  38   SCM mins = get_minimum_distances (me);
  39   SCM newdist = scm_from_double (d);
  40   for (SCM s = mins; scm_is_pair (s); s = scm_cdr (s))
  41     {
  42       SCM dist = scm_car (s);
  43       if (scm_car (dist) == p->self_scm ())
  44         {
  45           scm_set_cdr_x (dist, scm_max (scm_cdr (dist),
  46                                         newdist));
  47           return;
  48         }
  49     }
  50
  51   if (Paper_column::get_rank (p) < Paper_column::get_rank (me))
  52     programming_error ("Adding reverse rod");
  53
  54   mins = scm_cons (scm_cons (p->self_scm (), newdist), mins);
  55   me->set_object ("minimum-distances", mins);
  56 }
  57
  58 void
  59 Spaceable_grob::add_spring (Grob *me, Grob *other, Spring sp)
  60 {
  61   SCM ideal = me->get_object ("ideal-distances");
  62
  63   ideal = scm_cons (scm_cons (sp.smobbed_copy (), other->self_scm ()), ideal);
  64   me->set_object ("ideal-distances", ideal);
  65 }
  66
  67 Spring
  68 Spaceable_grob::get_spring (Grob *this_col, Grob *next_col)
  69 {
  70   Spring *spring = 0;
  71
  72   for (SCM s = this_col->get_object ("ideal-distances");
  73        !spring && scm_is_pair (s);
  74        s = scm_cdr (s))
  75     {
  76       if (scm_is_pair (scm_car (s))
  77           && unsmob_grob (scm_cdar (s)) == next_col
  78           && unsmob_spring (scm_caar (s)))
  79         spring = unsmob_spring (scm_caar (s));
  80     }
  81
  82   if (!spring)
  83     programming_error (_f ("No spring between column %d and next one",
  84                            Paper_column::get_rank (this_col)));
  85
  86   return spring ? *spring : Spring ();
  87 }
  88
  89
  90
  91 ADD_INTERFACE (Spaceable_grob,
  92                "A layout object that takes part in the spacing problem.",
  93
  94                /* properties */
  95                "allow-loose-spacing "
  96                "ideal-distances "
  97                "keep-inside-line "
  98                "left-neighbors "
  99                "measure-length "
 100                "minimum-distances "
 101                "right-neighbors "
 102                "spacing-wishes "
 103                );
 104