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--2003 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7
   8  */
   9 #include <math.h>
  10
  11 #include "axis-group-interface.hh"
  12 #include "system-start-delimiter.hh"
  13 #include "paper-def.hh"
  14 #include "molecule.hh"
  15 #include "font-interface.hh"
  16 #include "all-font-metrics.hh"
  17 #include "grob.hh"
  18 #include "staff-symbol-referencer.hh"
  19 #include "lookup.hh"
  20
  21 Molecule
  22 System_start_delimiter::staff_bracket (Grob*me,Real height)
  23 {
  24   Real arc_height = gh_scm2double (me->get_grob_property ("arch-height")) ;
  25
  26   SCM at = scm_list_n (ly_symbol2scm ("bracket"),
  27                     me->get_grob_property ("arch-angle"),
  28                     me->get_grob_property ("arch-width"),
  29                     gh_double2scm (arc_height),
  30                     gh_double2scm (height),
  31                     me->get_grob_property ("arch-thick"),
  32                     me->get_grob_property ("thickness"),
  33                     SCM_UNDEFINED);
  34
  35 /*
  36 TODO: sort this out.
  37
  38 Another thing:
  39 In system-start-delimiter.cc I see the line
  40
  41   Real h = height + 2 * arc_height;
  42
  43 But I really think that you mean
  44
  45  Real h = height + 2 * arc_width;
  46
  47 (arc_height changes the x-axis-size of arc ; arc_width changes the
  48 y-axis-size)
  49 Will not fix it since I'm not sure.
  50
  51    */
  52
  53   Real h = height + 2 * arc_height;
  54   Box b (Interval (0, 1.5), Interval (-h/2, h/2));
  55   Molecule mol (b, at);
  56   mol.align_to (X_AXIS, CENTER);
  57   return mol;
  58 }
  59
  60
  61
  62 Molecule
  63 System_start_delimiter::simple_bar (Grob*me,Real h)
  64 {
  65   Real w = me->get_paper ()->get_var ("linethickness") *
  66     gh_scm2double (me->get_grob_property ("thickness"));
  67   return Lookup::filledbox (Box (Interval (0,w), Interval (-h/2, h/2)));
  68 }
  69
  70 MAKE_SCHEME_CALLBACK (System_start_delimiter,after_line_breaking,1);
  71
  72 SCM
  73 System_start_delimiter::after_line_breaking (SCM smob)
  74 {
  75   Grob * me = unsmob_grob (smob);
  76   SCM   gl = me->get_grob_property ("glyph");
  77
  78   if (scm_ilength (me->get_grob_property ("elements")) <=  1
  79       && gh_equal_p (gl,scm_makfrom0str ("bar-line")))
  80     {
  81       me->suicide ();
  82     }
  83
  84   return SCM_UNSPECIFIED;
  85 }
  86
  87
  88 MAKE_SCHEME_CALLBACK (System_start_delimiter,brew_molecule,1);
  89 SCM
  90 System_start_delimiter::brew_molecule (SCM smob)
  91 {
  92   Grob * me = unsmob_grob (smob);
  93
  94   SCM s = me->get_grob_property ("glyph");
  95   if (!gh_string_p (s))
  96     return SCM_EOL;
  97   SCM gsym = scm_string_to_symbol (s) ;
  98   SCM c = me->get_grob_property ("collapse-height");
  99
 100   Real staff_space = Staff_symbol_referencer::staff_space (me);
 101   Interval ext = ly_scm2interval (Axis_group_interface::group_extent_callback
 102  (me->self_scm (), gh_int2scm (Y_AXIS)));
 103   Real l = ext.length () / staff_space;
 104
 105   if (ext.empty_b ()
 106       || (gh_number_p (c) && l <= gh_scm2double (c)))
 107     {
 108       me->suicide ();
 109       return SCM_EOL;
 110     }
 111
 112   Molecule m;
 113
 114   if (gsym== ly_symbol2scm ("bracket"))
 115     m = staff_bracket (me,l);
 116   else if (gsym == ly_symbol2scm ("brace"))
 117     m =  staff_brace (me,l);
 118   else if (gsym == ly_symbol2scm ("bar-line"))
 119     m = simple_bar (me,l);
 120
 121   m.translate_axis (ext.center (), Y_AXIS);
 122   return m.smobbed_copy ();
 123 }
 124
 125 Molecule
 126 System_start_delimiter::staff_brace (Grob*me, Real y)
 127 {
 128   Font_metric *fm = 0;
 129
 130   /* We go through the style sheet to lookup the font file
 131      name.  This is better than using find_font directly,
 132      esp. because that triggers mktextfm for non-existent
 133      fonts. */
 134   SCM br = ly_symbol2scm ("braces");
 135   SCM fam = gh_cons (ly_symbol2scm ("font-family"), br);
 136   SCM sz = gh_cons (ly_symbol2scm ("font-relative-size"), ly_symbol2scm ("*"));
 137
 138   SCM alist = scm_list_n (fam, sz, SCM_UNDEFINED);
 139   fm = Font_interface::get_font (me, scm_list_n (alist, SCM_UNDEFINED));
 140
 141
 142   int lo = 0;
 143
 144   int hi = (fm->count () - 1) >? 2;
 145   Box b;
 146
 147   /* do a binary search for each Y, not very efficient, but passable?  */
 148   do
 149     {
 150       int cmp = (lo + hi) / 2;
 151       b = fm->get_char (cmp);
 152       if (b[Y_AXIS].empty_b () || b[Y_AXIS].length () > y)
 153         hi = cmp;
 154       else
 155         lo = cmp;
 156     }
 157   while (hi - lo > 1);
 158
 159   Molecule m (fm->get_char_molecule (lo));
 160   b=m.extent_box();
 161   b[X_AXIS] = Interval (0,0);
 162
 163   return Molecule (b, m.get_expr());
 164 }
 165
 166
 167
 168
 169 ADD_INTERFACE (System_start_delimiter,"system-start-delimiter-interface",
 170   "#'style can be bar-line, bracket or brace",
 171   "collapse-height thickness arch-height arch-angle arch-thick arch-width bracket-thick glyph");