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--2004 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7
   8  */
   9 #include <stdio.h>
  10 #include <math.h>
  11
  12 #include "spaceable-grob.hh"
  13 #include "grob.hh"
  14 #include "warn.hh"
  15 #include "spring.hh"
  16 #include "group-interface.hh"
  17
  18 SCM
  19 Spaceable_grob::get_minimum_distances (Grob*me)
  20 {
  21   return me->get_property ("minimum-distances");
  22 }
  23
  24 /*todo: merge code of spring & rod?
  25  */
  26 void
  27 Spaceable_grob::add_rod (Grob *me , Grob * p, Real d)
  28 {
  29   //  printf ("rod %lf\n", d);
  30
  31
  32   SCM mins = get_minimum_distances (me);
  33   SCM newdist = scm_make_real (d);
  34   for (SCM s = mins; ly_c_pair_p (s); s = ly_cdr (s))
  35     {
  36       SCM dist = ly_car (s);
  37       if (ly_car (dist) == p->self_scm ())
  38         {
  39           scm_set_cdr_x (dist, scm_max (ly_cdr (dist),
  40                                        newdist));
  41           return ;
  42         }
  43     }
  44
  45   mins = scm_cons (scm_cons (p->self_scm (), newdist), mins);
  46   me->set_property ("minimum-distances", mins);
  47 }
  48
  49 void
  50 Spaceable_grob::add_spring (Grob*me, Grob * p, Real d, Real strength, bool expand_only)
  51 {
  52   //  printf ("dist %lf, str %lf\n", d, strength);
  53   if (d <= 0.0 || strength <= 0.0)
  54     {
  55       programming_error ("Adding reverse spring! Setting to unit spring");
  56       d = 1.0;
  57       strength = 1.0;
  58     }
  59
  60   if (isinf (d) || isnan(d)
  61       || isnan (strength))
  62     {
  63       /*
  64         strength == INF is possible. It means fixed distance.
  65        */
  66       programming_error ("Insane distance found.");
  67       d = 1.0;
  68       strength = 1.0;
  69     }
  70
  71 #ifndef NDEBUG
  72   SCM mins = me->get_property ("ideal-distances");
  73   for (SCM s = mins; ly_c_pair_p (s); s = ly_cdr (s))
  74     {
  75       Spring_smob * sp = unsmob_spring(ly_car (s));
  76       if (sp->other_ == p)
  77         {
  78           programming_error ("already have that spring");
  79           return ;
  80         }
  81     }
  82 #endif
  83
  84   Spring_smob spring;
  85   spring.strength_ = strength;
  86   spring.distance_ = d;
  87   spring.expand_only_b_ = expand_only;
  88   spring.other_ = p;
  89
  90   Group_interface::add_thing (me, ly_symbol2scm ("ideal-distances"), spring.smobbed_copy ());
  91 }
  92
  93
  94 void
  95 Spaceable_grob::remove_interface (Grob*me)
  96 {
  97   me->set_property ("minimum-distances" , SCM_EOL);
  98   me->set_property ("spacing-wishes", SCM_EOL);
  99   me->set_property ("ideal-distances", SCM_EOL);
 100 }
 101
 102
 103
 104 ADD_INTERFACE (Spaceable_grob,"spaceable-grob-interface",
 105                "A layout object that takes part in the spacing problem. "
 106                ,
 107                "measure-length spacing-wishes penalty minimum-distances ideal-distances "
 108                "left-neighbors right-neighbors");
 109