lily/system-start-delimiter.cc

   1 /*
   2   system-start-delimiter.cc -- implement System_start_delimiter
   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 "system-start-delimiter.hh"
  10 #include "text-interface.hh"
  11 #include "all-font-metrics.hh"
  12 #include "axis-group-interface.hh"
  13 #include "font-interface.hh"
  14 #include "item.hh"
  15 #include "line-interface.hh"
  16 #include "lookup.hh"
  17 #include "output-def.hh"
  18 #include "pointer-group-interface.hh"
  19 #include "spanner.hh"
  20 #include "staff-symbol-referencer.hh"
  21
  22 Stencil
  23 System_start_delimiter::staff_bracket (Grob *me, Real height)
  24 {
  25   SCM fam = scm_cons (ly_symbol2scm ("font-encoding"),
  26                       ly_symbol2scm ("fetaMusic"));
  27
  28   SCM alist = scm_list_n (fam, SCM_UNDEFINED);
  29   Font_metric *fm = select_font (me->layout (), scm_list_n (alist, SCM_UNDEFINED));
  30
  31   Drul_array<Stencil> tips (fm->find_by_name ("brackettips.down"),
  32                             fm->find_by_name ("brackettips.up"));
  33
  34   Real thickness = robust_scm2double (me->get_property ("thickness"), 0.25);
  35
  36   Real overlap = 0.1 * thickness;
  37
  38   Box box (Interval (0, thickness),
  39            Interval (-1, 1)
  40            * (height / 2 + overlap));
  41
  42   Stencil bracket = Lookup::filled_box (box);
  43   Direction d = DOWN;
  44   do
  45     bracket.add_at_edge (Y_AXIS, d, tips[d], -overlap);
  46   while (flip (&d) != DOWN);
  47   bracket = Stencil (box, bracket.expr ());
  48
  49   bracket.translate_axis (-0.8, X_AXIS);
  50
  51   return bracket;
  52 }
  53
  54 Stencil
  55 System_start_delimiter::line_bracket (Grob *me, Real height)
  56 {
  57   Real thick
  58     = me->layout ()->get_dimension (ly_symbol2scm ("line-thickness"))
  59     * robust_scm2double (me->get_property ("thickness"), 1);
  60   Real w = 0.8;
  61
  62   Stencil tip1 = Line_interface::make_line (thick,
  63                                            Offset (0, -height/2),
  64                                            Offset (w, -height/2));
  65   Stencil tip2 = Line_interface::make_line (thick,
  66                                             Offset (0, height/2),
  67                                             Offset (w, height/2));
  68   Stencil vline = Line_interface::make_line (thick,
  69                                              Offset (0, -height/2),
  70                                              Offset (0, height/2));
  71
  72   vline.add_stencil (tip1);
  73   vline.add_stencil (tip2);
  74   vline.translate_axis (-w, X_AXIS);
  75   return vline;
  76 }
  77
  78 Stencil
  79 System_start_delimiter::simple_bar (Grob *me, Real h)
  80 {
  81   Real lt = me->layout ()->get_dimension (ly_symbol2scm ("line-thickness"));
  82   Real w = lt * robust_scm2double (me->get_property ("thickness"), 1);
  83   return Lookup::round_filled_box (Box (Interval (0, w), Interval (-h / 2, h / 2)),
  84                                    lt);
  85 }
  86
  87 MAKE_SCHEME_CALLBACK (System_start_delimiter, print, 1);
  88 SCM
  89 System_start_delimiter::print (SCM smob)
  90 {
  91   Spanner *me = unsmob_spanner (smob);
  92   extract_grob_set (me, "elements", elts);
  93   Grob *common = common_refpoint_of_array (elts, me, Y_AXIS);
  94
  95   Interval ext;
  96   int non_empty_count = 0;
  97   for (vsize i = elts.size (); i--;)
  98     {
  99       Spanner *sp = dynamic_cast<Spanner *> (elts[i]);
 100
 101       if (sp
 102           && sp->get_bound (LEFT) == me->get_bound (LEFT))
 103         {
 104           Interval dims = sp->extent (common, Y_AXIS);
 105           if (!dims.is_empty ())
 106             {
 107               non_empty_count ++;
 108               ext.unite (dims);
 109             }
 110         }
 111     }
 112
 113   SCM glyph_sym = me->get_property ("style");
 114   Real len = ext.length ();
 115   if (ext.is_empty ()
 116       || (robust_scm2double (me->get_property ("collapse-height"), 0.0) >= ext.length ()))
 117     {
 118       me->suicide ();
 119       return SCM_UNSPECIFIED;
 120     }
 121
 122   Stencil m;
 123   if (glyph_sym == ly_symbol2scm ("bracket"))
 124     m = staff_bracket (me, len);
 125   else if (glyph_sym == ly_symbol2scm ("brace"))
 126     m = staff_brace (me, len);
 127   else if (glyph_sym == ly_symbol2scm ("bar-line"))
 128     m = simple_bar (me, len);
 129   else if (glyph_sym == ly_symbol2scm ("line-bracket"))
 130     m = line_bracket (me, len);
 131
 132   m.translate_axis (ext.center (), Y_AXIS);
 133   return m.smobbed_copy ();
 134 }
 135
 136 Stencil
 137 System_start_delimiter::staff_brace (Grob *me, Real y)
 138 {
 139   Font_metric *fm = 0;
 140   /* We go through the style sheet to lookup the font file
 141      name.  This is better than using find_font directly,
 142      esp. because that triggers mktextfm for non-existent
 143      fonts. */
 144   SCM fam = scm_cons (ly_symbol2scm ("font-encoding"),
 145                       ly_symbol2scm ("fetaBraces"));
 146
 147   SCM alist = scm_list_n (fam, SCM_UNDEFINED);
 148   fm = select_font (me->layout (), scm_list_n (alist, SCM_UNDEFINED));
 149
 150   int
 151     lo = 0;
 152   int hi = max ((int) fm->count () - 1, 2);
 153
 154   /* do a binary search for each Y, not very efficient, but passable?  */
 155   Box b;
 156   do
 157     {
 158       int cmp = (lo + hi) / 2;
 159       b = fm->get_indexed_char (cmp);
 160       if (b[Y_AXIS].is_empty () || b[Y_AXIS].length () > y)
 161         hi = cmp;
 162       else
 163         lo = cmp;
 164     }
 165   while (hi - lo > 1);
 166
 167   Stencil stil (fm->find_by_name ("brace" + to_string (lo)));
 168   stil.translate_axis (-b[X_AXIS].length ()/2, X_AXIS);
 169
 170   stil.translate_axis (-0.2, X_AXIS);
 171
 172   return stil;
 173 }
 174
 175 ADD_INTERFACE (System_start_delimiter,
 176                "The brace, bracket or bar in front of the system.  The"
 177                " following values for @code{style} are recognized:\n"
 178                "\n"
 179                "@table @code\n"
 180                "@item bracket\n"
 181                "A thick bracket, normally used to group similar"
 182                " instruments in a score.  Default for @code{StaffGroup}."
 183                "  @code{SystemStartBracket} uses this style.\n"
 184                "@item brace\n"
 185                "A @q{piano style} brace normally used for an instrument"
 186                " that uses two staves.  The default style for"
 187                " @code{GrandStaff}.  @code{SystemStartBrace} uses this"
 188                " style.\n"
 189                "@item bar-line\n"
 190                "A simple line between the staves in a score.  Default"
 191                " for staves enclosed in @code{<<} and @code{>>}."
 192                "  @code{SystemStartBar} uses this style.\n"
 193                "@item line-bracket\n"
 194                "A simple square, normally used for subgrouping"
 195                " instruments in a score.  @code{SystemStartSquare} uses"
 196                " this style.\n"
 197                "@end table\n"
 198                "\n"
 199                "See also @file{input/regression/system-start-nesting.ly}.",
 200
 201                /* properties */
 202                "collapse-height "
 203                "style "
 204                "thickness "
 205                );