lily/system-start-delimiter.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 2000--2010 Han-Wen Nienhuys <hanwen@xs4all.nl>
   5
   6   LilyPond is free software: you can redistribute it and/or modify
   7   it under the terms of the GNU General Public License as published by
   8   the Free Software Foundation, either version 3 of the License, or
   9   (at your option) any later version.
  10
  11   LilyPond is distributed in the hope that it will be useful,
  12   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14   GNU General Public License for more details.
  15
  16   You should have received a copy of the GNU General Public License
  17   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "system-start-delimiter.hh"
  21 #include "text-interface.hh"
  22 #include "all-font-metrics.hh"
  23 #include "axis-group-interface.hh"
  24 #include "font-interface.hh"
  25 #include "item.hh"
  26 #include "line-interface.hh"
  27 #include "lookup.hh"
  28 #include "output-def.hh"
  29 #include "pointer-group-interface.hh"
  30 #include "spanner.hh"
  31 #include "staff-symbol-referencer.hh"
  32
  33 Stencil
  34 System_start_delimiter::staff_bracket (Grob *me, Real height)
  35 {
  36   Font_metric *fm = Font_interface::get_default_font (me);
  37
  38   Drul_array<Stencil> tips (fm->find_by_name ("brackettips.down"),
  39                             fm->find_by_name ("brackettips.up"));
  40
  41   Real thickness = robust_scm2double (me->get_property ("thickness"), 0.25);
  42
  43   Real overlap = 0.1 * thickness;
  44
  45   Box box (Interval (0, thickness),
  46            Interval (-1, 1)
  47            * (height / 2 + overlap));
  48
  49   Stencil bracket = Lookup::filled_box (box);
  50   Direction d = DOWN;
  51   do
  52     bracket.add_at_edge (Y_AXIS, d, tips[d], -overlap);
  53   while (flip (&d) != DOWN);
  54   bracket = Stencil (box, bracket.expr ());
  55
  56   bracket.translate_axis (-0.8, X_AXIS);
  57
  58   return bracket;
  59 }
  60
  61 Stencil
  62 System_start_delimiter::line_bracket (Grob *me, Real height)
  63 {
  64   Real thick
  65     = me->layout ()->get_dimension (ly_symbol2scm ("line-thickness"))
  66     * robust_scm2double (me->get_property ("thickness"), 1);
  67   Real w = 0.8;
  68
  69   Stencil tip1 = Line_interface::make_line (thick,
  70                                            Offset (0, -height/2),
  71                                            Offset (w, -height/2));
  72   Stencil tip2 = Line_interface::make_line (thick,
  73                                             Offset (0, height/2),
  74                                             Offset (w, height/2));
  75   Stencil vline = Line_interface::make_line (thick,
  76                                              Offset (0, -height/2),
  77                                              Offset (0, height/2));
  78
  79   vline.add_stencil (tip1);
  80   vline.add_stencil (tip2);
  81   vline.translate_axis (-w, X_AXIS);
  82   return vline;
  83 }
  84
  85 Stencil
  86 System_start_delimiter::simple_bar (Grob *me, Real h)
  87 {
  88   Real lt = me->layout ()->get_dimension (ly_symbol2scm ("line-thickness"));
  89   Real w = lt * robust_scm2double (me->get_property ("thickness"), 1);
  90   return Lookup::round_filled_box (Box (Interval (0, w), Interval (-h / 2, h / 2)),
  91                                    lt);
  92 }
  93
  94 MAKE_SCHEME_CALLBACK (System_start_delimiter, print, 1);
  95 SCM
  96 System_start_delimiter::print (SCM smob)
  97 {
  98   Spanner *me = unsmob_spanner (smob);
  99   extract_grob_set (me, "elements", elts);
 100   Grob *common = common_refpoint_of_array (elts, me, Y_AXIS);
 101
 102   Interval ext;
 103   int non_empty_count = 0;
 104   for (vsize i = elts.size (); i--;)
 105     {
 106       Spanner *sp = dynamic_cast<Spanner *> (elts[i]);
 107
 108       if (sp
 109           && sp->get_bound (LEFT) == me->get_bound (LEFT))
 110         {
 111           Interval dims = sp->extent (common, Y_AXIS);
 112           if (!dims.is_empty ())
 113             {
 114               non_empty_count ++;
 115               ext.unite (dims);
 116             }
 117         }
 118     }
 119
 120   SCM glyph_sym = me->get_property ("style");
 121   Real len = ext.length ();
 122   if (ext.is_empty ()
 123       || (robust_scm2double (me->get_property ("collapse-height"), 0.0) >= ext.length ()))
 124     {
 125       me->suicide ();
 126       return SCM_UNSPECIFIED;
 127     }
 128
 129   Stencil m;
 130   if (glyph_sym == ly_symbol2scm ("bracket"))
 131     m = staff_bracket (me, len);
 132   else if (glyph_sym == ly_symbol2scm ("brace"))
 133     m = staff_brace (me, len);
 134   else if (glyph_sym == ly_symbol2scm ("bar-line"))
 135     m = simple_bar (me, len);
 136   else if (glyph_sym == ly_symbol2scm ("line-bracket"))
 137     m = line_bracket (me, len);
 138
 139   m.translate_axis (ext.center (), Y_AXIS);
 140   return m.smobbed_copy ();
 141 }
 142
 143 Stencil
 144 System_start_delimiter::staff_brace (Grob *me, Real y)
 145 {
 146   Font_metric *fm = 0;
 147
 148   /*
 149     Find the default brace font if the user overrides it.
 150   */
 151   fm = Font_interface::get_default_font (me);
 152
 153   int
 154     lo = 0;
 155   int hi = max ((int) fm->count () - 1, 2);
 156
 157   /* do a binary search for each Y, not very efficient, but passable?  */
 158   Box b;
 159   do
 160     {
 161       int cmp = (lo + hi) / 2;
 162       b = fm->get_indexed_char_dimensions (cmp);
 163       if (b[Y_AXIS].is_empty () || b[Y_AXIS].length () > y)
 164         hi = cmp;
 165       else
 166         lo = cmp;
 167     }
 168   while (hi - lo > 1);
 169
 170   Stencil stil (fm->find_by_name ("brace" + to_string (lo)));
 171   stil.translate_axis (-b[X_AXIS].length ()/2, X_AXIS);
 172
 173   stil.translate_axis (-0.2, X_AXIS);
 174
 175   return stil;
 176 }
 177
 178 ADD_INTERFACE (System_start_delimiter,
 179                "The brace, bracket or bar in front of the system.  The"
 180                " following values for @code{style} are recognized:\n"
 181                "\n"
 182                "@table @code\n"
 183                "@item bracket\n"
 184                "A thick bracket, normally used to group similar"
 185                " instruments in a score.  Default for @code{StaffGroup}."
 186                "  @code{SystemStartBracket} uses this style.\n"
 187                "@item brace\n"
 188                "A @q{piano style} brace normally used for an instrument"
 189                " that uses two staves.  The default style for"
 190                " @code{GrandStaff}.  @code{SystemStartBrace} uses this"
 191                " style.\n"
 192                "@item bar-line\n"
 193                "A simple line between the staves in a score.  Default"
 194                " for staves enclosed in @code{<<} and @code{>>}."
 195                "  @code{SystemStartBar} uses this style.\n"
 196                "@item line-bracket\n"
 197                "A simple square, normally used for subgrouping"
 198                " instruments in a score.  @code{SystemStartSquare} uses"
 199                " this style.\n"
 200                "@end table\n"
 201                "\n"
 202                "See also @file{input/regression/system-start-nesting.ly}.",
 203
 204                /* properties */
 205                "collapse-height "
 206                "style "
 207                "thickness "
 208                );