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--2007 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7 */
   8
   9 #include "span-bar.hh"
  10
  11 #include "font-interface.hh"
  12 #include "dimensions.hh"
  13 #include "output-def.hh"
  14 #include "stencil.hh"
  15 #include "warn.hh"
  16 #include "axis-group-interface.hh"
  17 #include "bar-line.hh"
  18 #include "grob.hh"
  19 #include "pointer-group-interface.hh"
  20
  21 void
  22 Span_bar::add_bar (Grob *me, Grob *b)
  23 {
  24   Pointer_group_interface::add_grob (me, ly_symbol2scm ("elements"), b);
  25 }
  26
  27 MAKE_SCHEME_CALLBACK (Span_bar, print, 1);
  28
  29 /* Limitations/Bugs:
  30
  31 (1) Elements from 'me->get_object ("elements")' must be
  32 ordered according to their y coordinates relative to their common
  33 axis group parent.  Otherwise, the computation goes mad.
  34
  35 (2) This method depends on bar_engraver not being removed from
  36 staff context.  If bar_engraver is removed, the size of the staff
  37 lines is evaluated as 0, which results in a solid span bar line
  38 with faulty y coordinate. */
  39
  40 /* This routine was originally by Juergen Reuter, but it was a on the
  41    bulky side. Rewritten by Han-Wen. */
  42 SCM
  43 Span_bar::print (SCM smobbed_me)
  44 {
  45   Grob *me = unsmob_grob (smobbed_me);
  46   extract_grob_set (me, "elements", elements);
  47   Grob *refp = common_refpoint_of_array (elements, me, Y_AXIS);
  48
  49   SCM glyph = me->get_property ("glyph-name");
  50
  51   /* glyph may not be a string, when ME is killed by Hara Kiri in
  52      between. */
  53   if (!scm_is_string (glyph))
  54     return SCM_EOL;
  55
  56   string glyph_string = ly_scm2string (glyph);
  57
  58   /* compose span_bar_mol */
  59   vector<Interval> extents;
  60   Grob *model_bar = 0;
  61   for (vsize i = elements.size (); i--;)
  62     {
  63       Grob *bar = elements[i];
  64       Interval ext = bar->extent (refp, Y_AXIS);
  65       if (ext.is_empty () || to_boolean (bar->get_property ("transparent")))
  66         continue;
  67
  68       extents.push_back (ext);
  69       model_bar = bar;
  70     }
  71
  72   if (!model_bar)
  73     model_bar = me;
  74
  75   vector_sort (extents, Interval::left_less);
  76
  77   Stencil span_bar;
  78   for (vsize i = 1; i < extents.size (); i++)
  79     {
  80       Interval prev_extent = extents[i - 1];
  81       Interval ext = extents[i];
  82       if (!prev_extent.is_empty ())
  83         {
  84           Interval l (prev_extent [UP],
  85                       ext[DOWN]);
  86
  87           if (l.is_empty ())
  88             {
  89               /* There is overlap between the bar lines.  Do nothing. */
  90             }
  91           else
  92             {
  93               Stencil interbar = Bar_line::compound_barline (model_bar,
  94                                                              glyph_string,
  95                                                              l.length (),
  96                                                              false);
  97               interbar.translate_axis (l.center (), Y_AXIS);
  98               span_bar.add_stencil (interbar);
  99             }
 100         }
 101       prev_extent = ext;
 102     }
 103
 104   span_bar.translate_axis (- me->relative_coordinate (refp, Y_AXIS),
 105                            Y_AXIS);
 106
 107   return span_bar.smobbed_copy ();
 108 }
 109
 110 MAKE_SCHEME_CALLBACK (Span_bar, width, 1);
 111 SCM
 112 Span_bar::width (SCM smob)
 113 {
 114   Grob *me = unsmob_grob (smob);
 115   SCM gn = me->get_property ("glyph-name");
 116   if (!me->is_live ())
 117     return ly_interval2scm (Interval ());
 118
 119   string gl = ly_scm2string (gn);
 120
 121   /*
 122     urg.
 123   */
 124   Stencil m = Bar_line::compound_barline (me, gl, 40 PT, false);
 125
 126   return ly_interval2scm (m.extent (X_AXIS));
 127 }
 128
 129 MAKE_SCHEME_CALLBACK (Span_bar, before_line_breaking, 1);
 130 SCM
 131 Span_bar::before_line_breaking (SCM smob)
 132 {
 133   Grob *me = unsmob_grob (smob);
 134   extract_grob_set (me, "elements", elements);
 135   if (elements.empty ())
 136     me->suicide ();
 137
 138   return SCM_UNSPECIFIED;
 139 }
 140
 141 MAKE_SCHEME_CALLBACK (Span_bar, center_on_spanned_callback, 1);
 142
 143 SCM
 144 Span_bar::center_on_spanned_callback (SCM smob)
 145 {
 146   Grob *me = unsmob_grob (smob);
 147   Interval i (get_spanned_interval (me));
 148
 149   /* Bar_line::print delivers a barline of y-extent (-h/2, h/2), so
 150      we have to translate ourselves to be in the center of the
 151      interval that we span. */
 152   if (i.is_empty ())
 153     {
 154       me->suicide ();
 155       return scm_from_double (0.0);
 156     }
 157
 158   return scm_from_double (i.center ());
 159 }
 160
 161
 162
 163 MAKE_SCHEME_CALLBACK(Span_bar, calc_glyph_name, 1);
 164 SCM
 165 Span_bar::calc_glyph_name (SCM smob)
 166 {
 167   Grob *me = unsmob_grob (smob);
 168   extract_grob_set (me, "elements", elements);
 169   SCM gl = SCM_EOL;
 170   for (vsize i = elements.size ();
 171        i-- && !scm_is_string (gl);)
 172     gl = elements[i]->get_property ("glyph-name");
 173
 174   if (!scm_is_string (gl))
 175     {
 176       me->suicide ();
 177       return SCM_UNSPECIFIED;
 178     }
 179
 180   string type = ly_scm2string (gl);
 181   if (type == "|:")
 182     type = ".|";
 183   else if (type == ":|")
 184     type = "|.";
 185   else if (type == ":|:")
 186     type = ".|.";
 187
 188   return ly_string2scm (type);
 189 }
 190
 191 Interval
 192 Span_bar::get_spanned_interval (Grob *me)
 193 {
 194   return ly_scm2interval (Axis_group_interface::generic_group_extent (me, Y_AXIS));
 195 }
 196
 197 MAKE_SCHEME_CALLBACK (Span_bar, calc_bar_size, 1);
 198 SCM
 199 Span_bar::calc_bar_size (SCM smob)
 200 {
 201   Grob *me = unsmob_grob (smob);
 202   Interval iv (get_spanned_interval (me));
 203   if (iv.is_empty ())
 204     {
 205       /* This happens if the bars are hara-kiried from under us. */
 206       me->suicide ();
 207       return scm_from_double (-1);
 208     }
 209   return scm_from_double (iv.length ());
 210 }
 211
 212 ADD_INTERFACE (Span_bar,
 213                "A bar line that spanned between other barlines. This interface is "
 214                " used for  bar lines that connect different staves.",
 215
 216                /* properties */
 217                "glyph-name "
 218                "elements");
 219