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--2009 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   vector<bool> make_span_bar;
  61   Grob *model_bar = 0;
  62   for (vsize i = elements.size (); i--;)
  63     {
  64       Grob *bar = elements[i];
  65       Interval ext = Bar_line::bar_y_extent (bar, refp);
  66       if (ext.is_empty ())
  67         continue;
  68
  69       extents.push_back (ext);
  70       make_span_bar.push_back (to_boolean (bar->get_property ("allow-span-bar")));
  71       model_bar = bar;
  72     }
  73
  74   if (!model_bar)
  75     model_bar = me;
  76
  77   vector_sort (extents, Interval::left_less);
  78
  79   Stencil span_bar;
  80   for (vsize i = 1; i < extents.size (); i++)
  81     {
  82       Interval prev_extent = extents[i - 1];
  83       Interval ext = extents[i];
  84       if (!prev_extent.is_empty ())
  85         {
  86           Interval l (prev_extent [UP],
  87                       ext[DOWN]);
  88
  89           if (l.is_empty () || !make_span_bar[i])
  90             {
  91               /* There is overlap between the bar lines.  Do nothing. */
  92             }
  93           else
  94             {
  95               Stencil interbar = Bar_line::compound_barline (model_bar,
  96                                                              glyph_string,
  97                                                              l.length (),
  98                                                              false);
  99               interbar.translate_axis (l.center (), Y_AXIS);
 100               span_bar.add_stencil (interbar);
 101             }
 102         }
 103       prev_extent = ext;
 104     }
 105
 106   span_bar.translate_axis (- me->relative_coordinate (refp, Y_AXIS),
 107                            Y_AXIS);
 108
 109   return span_bar.smobbed_copy ();
 110 }
 111
 112 MAKE_SCHEME_CALLBACK (Span_bar, width, 1);
 113 SCM
 114 Span_bar::width (SCM smob)
 115 {
 116   Grob *me = unsmob_grob (smob);
 117   SCM gn = me->get_property ("glyph-name");
 118   if (!me->is_live ())
 119     return ly_interval2scm (Interval ());
 120
 121   string gl = ly_scm2string (gn);
 122
 123   /*
 124     urg.
 125   */
 126   Stencil m = Bar_line::compound_barline (me, gl, 40 PT, false);
 127
 128   return ly_interval2scm (m.extent (X_AXIS));
 129 }
 130
 131 MAKE_SCHEME_CALLBACK (Span_bar, before_line_breaking, 1);
 132 SCM
 133 Span_bar::before_line_breaking (SCM smob)
 134 {
 135   Grob *me = unsmob_grob (smob);
 136   extract_grob_set (me, "elements", elements);
 137   if (elements.empty ())
 138     me->suicide ();
 139
 140   return SCM_UNSPECIFIED;
 141 }
 142
 143 MAKE_SCHEME_CALLBACK (Span_bar, center_on_spanned_callback, 1);
 144
 145 SCM
 146 Span_bar::center_on_spanned_callback (SCM smob)
 147 {
 148   Grob *me = unsmob_grob (smob);
 149   Interval i (get_spanned_interval (me));
 150
 151   /* Bar_line::print delivers a barline of y-extent (-h/2, h/2), so
 152      we have to translate ourselves to be in the center of the
 153      interval that we span. */
 154   if (i.is_empty ())
 155     {
 156       me->suicide ();
 157       return scm_from_double (0.0);
 158     }
 159
 160   return scm_from_double (i.center ());
 161 }
 162
 163
 164
 165 MAKE_SCHEME_CALLBACK(Span_bar, calc_glyph_name, 1);
 166 SCM
 167 Span_bar::calc_glyph_name (SCM smob)
 168 {
 169   Grob *me = unsmob_grob (smob);
 170   extract_grob_set (me, "elements", elements);
 171   SCM gl = SCM_EOL;
 172   for (vsize i = elements.size ();
 173        i-- && !scm_is_string (gl);)
 174     gl = elements[i]->get_property ("glyph-name");
 175
 176   if (!scm_is_string (gl))
 177     {
 178       me->suicide ();
 179       return SCM_UNSPECIFIED;
 180     }
 181
 182   string type = ly_scm2string (gl);
 183   if (type == "|:")
 184     type = ".|";
 185   else if (type == ":|")
 186     type = "|.";
 187   else if (type == ":|:")
 188     type = ".|.";
 189   else if (type == ":|.|:")
 190     type = "|.|";
 191   else if (type == ":|.:")
 192     type = "|.";
 193   else if (type == "'")
 194     type = "";
 195
 196   return ly_string2scm (type);
 197 }
 198
 199 Interval
 200 Span_bar::get_spanned_interval (Grob *me)
 201 {
 202   return ly_scm2interval (Axis_group_interface::generic_group_extent (me, Y_AXIS));
 203 }
 204
 205 MAKE_SCHEME_CALLBACK (Span_bar, calc_bar_size, 1);
 206 SCM
 207 Span_bar::calc_bar_size (SCM smob)
 208 {
 209   Grob *me = unsmob_grob (smob);
 210   Interval iv (get_spanned_interval (me));
 211   if (iv.is_empty ())
 212     {
 213       /* This happens if the bars are hara-kiried from under us. */
 214       me->suicide ();
 215       return scm_from_double (-1);
 216     }
 217   return scm_from_double (iv.length ());
 218 }
 219
 220 ADD_INTERFACE (Span_bar,
 221                "A bar line that is spanned between other barlines.  This"
 222                " interface is used for bar lines that connect different"
 223                " staves.",
 224
 225                /* properties */
 226                "glyph-name "
 227                "elements "
 228                );
 229