lily/font-metric.cc

   1 /*
   2   font-metric.cc --  implement Font_metric
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1999--2002 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7
   8     Mats Bengtsson <matsb@s3.kth.se> (the ugly TeX parsing in text_dimension)
   9  */
  10
  11 #include <math.h>
  12 #include <ctype.h>
  13
  14 #include "warn.hh"
  15 #include "molecule.hh"
  16 #include "ly-smobs.icc"
  17 #include "font-metric.hh"
  18 #include "string.hh"
  19
  20 Box
  21 Font_metric::text_dimension (String text) const
  22 {
  23   Interval ydims;
  24   Real w=0.0;
  25
  26   for (int i = 0; i < text.length (); i++)
  27     {
  28
  29       switch (text[i])
  30         {
  31         case '\\':
  32   // accent marks use width of base letter
  33          if (i +1 < text.length ())
  34            {
  35              if (text[i+1]=='\'' || text[i+1]=='`' || text[i+1]=='"' ||
  36                  text[i+1]=='^')
  37                {
  38                  i++;
  39                  break;
  40                }
  41              // for string width \\ is a \ and \_ is a _.
  42              if (text[i+1]=='\\' || text[i+1]=='_')
  43                {
  44                  break;
  45                }
  46            }
  47
  48           for (i++; (i < text.length ()) && !isspace (text[i])
  49                  && text[i]!='{' && text[i]!='}'; i++)
  50             ;
  51           // ugh.
  52           i--; // Compensate for the increment in the outer loop!
  53           break;
  54         case '{':  // Skip '{' and '}'
  55         case '}':
  56           break;
  57
  58         default:
  59           Box b = get_char ((unsigned char)text[i]);
  60
  61           // Ugh, use the width of 'x' for unknown characters
  62           if (b[X_AXIS].length () == 0)
  63             b = get_char ((unsigned char)'x');
  64
  65           w += b[X_AXIS].length ();
  66           ydims.unite (b[Y_AXIS]);
  67           break;
  68         }
  69     }
  70   if (ydims.empty_b ())
  71     ydims = Interval (0,0);
  72
  73   return Box (Interval (0, w), ydims);
  74 }
  75
  76
  77
  78 Font_metric::~Font_metric ()
  79 {
  80 }
  81
  82 Font_metric::Font_metric ()
  83 {
  84   description_ = SCM_EOL;
  85
  86   smobify_self ();
  87 }
  88
  89 Font_metric::Font_metric (Font_metric const &)
  90 {
  91 }
  92
  93 int
  94 Font_metric::count () const
  95 {
  96   return 0;
  97 }
  98
  99 Box
 100 Font_metric::get_char (int)const
 101 {
 102   return Box (Interval (0,0),Interval (0,0));
 103 }
 104
 105
 106 void
 107 Font_metric::derived_mark ()
 108 {
 109
 110 }
 111
 112
 113
 114 SCM
 115 Font_metric::mark_smob (SCM s)
 116 {
 117   Font_metric * m = (Font_metric*) SCM_CELL_WORD_1 (s);
 118
 119   do_derived_mark();
 120   return m->description_;
 121 }
 122
 123 int
 124 Font_metric::print_smob (SCM s, SCM port, scm_print_state *)
 125 {
 126   Font_metric *m = unsmob_metrics (s);
 127   scm_puts ("#<Font_metric ", port);
 128   scm_write (m->description_, port);
 129   scm_puts (">", port);
 130   return 1;
 131 }
 132
 133
 134
 135 IMPLEMENT_SMOBS (Font_metric);
 136 IMPLEMENT_DEFAULT_EQUAL_P (Font_metric);
 137 IMPLEMENT_TYPE_P (Font_metric, "font-metric?");
 138
 139 Molecule
 140 Font_metric::find_by_name (String) const
 141 {
 142   Molecule m ;
 143   return m;
 144 }
 145
 146
 147 LY_DEFINE(ly_find_glyph_by_name, "ly-find-glyph-by-name", 2 , 0, 0,
 148           (SCM font, SCM name),
 149           "This function retrieves a Molecule for the glyph named @var{name} in
 150 @var{font}.  The font must be available as an AFM file.")
 151 {
 152   Font_metric *fm = unsmob_metrics (font);
 153   SCM_ASSERT_TYPE(fm, font, SCM_ARG1, __FUNCTION__, "font-metric");
 154   SCM_ASSERT_TYPE(gh_string_p (name), name, SCM_ARG2, __FUNCTION__, "string");
 155
 156   return fm->find_by_name (ly_scm2string (name)).smobbed_copy ();
 157 }
 158
 159
 160 LY_DEFINE(ly_text_dimension,"ly-text-dimension", 2 , 0, 0,
 161           (SCM font, SCM text),
 162           "Given the font metric in @var{font} and the string @var{text}, compute
 163 the extents of that text in that font. The return value is a pair of
 164 number-pairs.")
 165 {
 166   Box b;
 167   Font_metric *fm = unsmob_metrics (font);
 168   SCM_ASSERT_TYPE(fm, font, SCM_ARG1, __FUNCTION__, "font-metric");
 169   SCM_ASSERT_TYPE(gh_string_p (text), text, SCM_ARG2, __FUNCTION__, "string");
 170
 171   b = fm->text_dimension (ly_scm2string (text));
 172
 173   return gh_cons (ly_interval2scm (b[X_AXIS]), ly_interval2scm(b[Y_AXIS]));
 174 }
 175
 176