lily/span-bar.cc

   1 /*
   2   span-bar.cc -- implement Span_bar
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c)  1997--2001 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7 */
   8
   9 #include "span-bar.hh"
  10 #include "font-interface.hh"
  11 #include "dimensions.hh"
  12 #include "paper-def.hh"
  13 #include "molecule.hh"
  14 #include "warn.hh"
  15 #include "axis-group-interface.hh"
  16 #include "group-interface.hh"
  17 #include "grob.hh"
  18 #include "bar.hh"
  19
  20 void
  21 Span_bar::add_bar (Grob*me, Grob*b)
  22 {
  23   Pointer_group_interface::add_element (me,"elements", b);
  24
  25   me->add_dependency (b);
  26 }
  27
  28 MAKE_SCHEME_CALLBACK (Span_bar,width_callback,2);
  29 SCM
  30 Span_bar::width_callback (SCM element_smob, SCM scm_axis)
  31 {
  32   Grob *se = unsmob_grob (element_smob);
  33   Axis a = (Axis) gh_scm2int (scm_axis);
  34   assert (a == X_AXIS);
  35   String gl = ly_scm2string (se->get_grob_property ("glyph"));
  36
  37   /*
  38     urg.
  39    */
  40   Molecule m = Bar::compound_barline (se, gl, 40 PT);
  41
  42   return ly_interval2scm (m.extent (X_AXIS));
  43 }
  44
  45 MAKE_SCHEME_CALLBACK (Span_bar,before_line_breaking,1);
  46 SCM
  47 Span_bar::before_line_breaking (SCM smob)
  48 {
  49   evaluate_empty (unsmob_grob (smob));
  50   evaluate_glyph (unsmob_grob (smob));
  51
  52   /*
  53     no need to call   Bar::before_line_breaking (), because the info
  54     in ELEMENTS already has been procced by Bar::before_line_breaking ().
  55    */
  56   return SCM_UNSPECIFIED;
  57 }
  58
  59 MAKE_SCHEME_CALLBACK (Span_bar,center_on_spanned_callback,2);
  60
  61 SCM
  62 Span_bar::center_on_spanned_callback (SCM element_smob, SCM axis)
  63 {
  64   Grob *me = unsmob_grob (element_smob);
  65   Axis a = (Axis) gh_scm2int (axis);
  66   assert (a == Y_AXIS);
  67   Interval i (get_spanned_interval (me));
  68
  69   /*
  70     Bar::brew_molecule delivers a barline of y-extent (-h/2,h/2), so
  71     we have to translate ourselves to be in the center of the
  72     interval that we span.  */
  73   if (i.empty_b ())
  74     {
  75       me->suicide ();
  76       return gh_double2scm (0.0);
  77     }
  78
  79   return gh_double2scm (i.center ());
  80 }
  81
  82 void
  83 Span_bar::evaluate_empty (Grob*me)
  84 {
  85   /*
  86     TODO: filter all hara-kiried out of ELEMENS list, and then
  87     optionally do suicide. Call this cleanage function from
  88     center_on_spanned_callback () as well.
  89
  90    */
  91   if (!gh_pair_p (me->get_grob_property ("elements")))
  92     {
  93       me->suicide ();
  94     }
  95 }
  96
  97 void
  98 Span_bar::evaluate_glyph (Grob*me)
  99 {
 100   SCM elts = me->get_grob_property ("elements");
 101   Grob * b = unsmob_grob (gh_car (elts));
 102   SCM glsym =ly_symbol2scm ("glyph");
 103   SCM gl =b ->get_grob_property (glsym);
 104   if (!gh_string_p (gl))
 105     {
 106       me->suicide ();
 107       return ;
 108     }
 109
 110   String type = ly_scm2string (gl);
 111
 112   if (type == "|:")
 113     {
 114       type = ".|";
 115     }
 116   else if (type== ":|")
 117     {
 118       type = "|.";
 119     }
 120   else if (type== ":|:")
 121     {
 122       type = ".|.";
 123     }
 124
 125   gl = ly_str02scm (type.ch_C ());
 126   if (scm_equal_p (me->get_grob_property (glsym), gl) != SCM_BOOL_T)
 127     me->set_grob_property (glsym, gl);
 128 }
 129
 130 Interval
 131 Span_bar::get_spanned_interval (Grob*me)
 132 {
 133   return ly_scm2interval (Axis_group_interface::group_extent_callback (me->self_scm (), gh_int2scm (Y_AXIS)));
 134 }
 135
 136
 137 MAKE_SCHEME_CALLBACK (Span_bar,get_bar_size,1);
 138 SCM
 139 Span_bar::get_bar_size (SCM smob)
 140 {
 141   Grob* me =  unsmob_grob (smob);
 142   Interval iv (get_spanned_interval (me));
 143   if (iv.empty_b ())
 144     {
 145       /*
 146         This happens if the bars are hara-kiried from under us.
 147        */
 148       me->suicide ();
 149       return gh_double2scm (-1);
 150     }
 151   return gh_double2scm (iv.length ());
 152 }
 153
 154 void
 155 Span_bar::set_interface (Grob *me)
 156 {
 157   Bar::set_interface (me);
 158
 159   me->set_interface (ly_symbol2scm ("span-bar-interface"));
 160   me->set_extent_callback (SCM_EOL, Y_AXIS);
 161 }
 162
 163 bool
 164 Span_bar::has_interface (Grob*m)
 165 {
 166   return m && m->has_interface (ly_symbol2scm ("span-bar-interface"));
 167 }