lily/text-interface.cc

   1 /*
   2   text-interface.cc -- implement Text_interface
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1998--2009 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7   Jan Nieuwenhuizen <janneke@gnu.org>
   8 */
   9
  10 #include "text-interface.hh"
  11
  12 #include "config.hh"
  13 #include "font-interface.hh"
  14 #include "grob.hh"
  15 #include "main.hh"
  16 #include "misc.hh"
  17 #include "modified-font-metric.hh"
  18 #include "output-def.hh"
  19 #include "pango-font.hh"
  20 #include "warn.hh"
  21
  22 static void
  23 replace_whitespace (string *str)
  24 {
  25   vsize i = 0;
  26   vsize n = str->size ();
  27
  28   while (i < n)
  29     {
  30       char cur = (*str)[i];
  31
  32       // avoid the locale-dependent isspace
  33       if (cur == '\n' || cur == '\t' || cur == '\v')
  34         (*str)[i] = ' ';
  35
  36       vsize char_len = utf8_char_len (cur);
  37
  38       i += char_len;
  39     }
  40 }
  41
  42 MAKE_SCHEME_CALLBACK (Text_interface, interpret_string, 3);
  43 SCM
  44 Text_interface::interpret_string (SCM layout_smob,
  45                                   SCM props,
  46                                   SCM markup)
  47 {
  48   LY_ASSERT_SMOB (Output_def, layout_smob, 1);
  49   LY_ASSERT_TYPE (scm_is_string, markup, 3);
  50
  51   string str = ly_scm2string (markup);
  52   Output_def *layout = unsmob_output_def (layout_smob);
  53   Font_metric *fm = select_encoded_font (layout, props);
  54
  55   replace_whitespace (&str);
  56
  57   /*
  58     We want to use "glyph-string" in the SVG backend for all
  59     music fonts (Emmentaler and Aybabtu) that pass through the
  60     text interface.  Here the font encoding is checked to see if
  61     it matches one of the music font encodings.  --pmccarty
  62   */
  63   SCM encoding = ly_chain_assoc_get (ly_symbol2scm ("font-encoding"),
  64                                      props,
  65                                      SCM_BOOL_F);
  66   SCM music_encodings = ly_lily_module_constant ("all-music-font-encodings");
  67
  68   if (scm_memq (encoding, music_encodings) != SCM_BOOL_F)
  69     return fm->word_stencil (str, true).smobbed_copy ();
  70   else
  71     return fm->word_stencil (str, false).smobbed_copy ();
  72 }
  73
  74 MAKE_SCHEME_CALLBACK_WITH_OPTARGS (Text_interface, interpret_markup, 3, 0,
  75                                    "Convert a text markup into a stencil."
  76 "  Takes three arguments, @var{layout}, @var{props}, and @var{markup}.\n"
  77 "\n"
  78 "@var{layout} is a @code{\\layout} block; it may be obtained from a grob with"
  79 " @code{ly:grob-layout}.  @var{props} is an alist chain, i.e. a list of"
  80 "  alists.  This is typically obtained with"
  81 " @code{(ly:grob-alist-chain grob (ly:output-def-lookup layout 'text-font-defaults))}."
  82 "  @var{markup} is the markup text to be processed.");
  83 SCM
  84 Text_interface::interpret_markup (SCM layout_smob, SCM props, SCM markup)
  85 {
  86   if (scm_is_string (markup))
  87     return interpret_string (layout_smob, props, markup);
  88   else if (scm_is_pair (markup))
  89     {
  90       SCM func = scm_car (markup);
  91       SCM args = scm_cdr (markup);
  92       if (!is_markup (markup))
  93         programming_error ("markup head has no markup signature");
  94
  95       return scm_apply_2 (func, layout_smob, props, args);
  96     }
  97   else
  98     {
  99       programming_error ("Object is not a markup. ");
 100       scm_puts ("This object should be a markup: ", scm_current_error_port ());
 101       scm_display (markup, scm_current_error_port ());
 102       scm_puts ("\n", scm_current_error_port ());
 103
 104       Box b;
 105       b[X_AXIS].set_empty ();
 106       b[Y_AXIS].set_empty ();
 107
 108       Stencil s (b, SCM_EOL);
 109       return s.smobbed_copy ();
 110     }
 111 }
 112
 113 MAKE_SCHEME_CALLBACK (Text_interface, print, 1);
 114 SCM
 115 Text_interface::print (SCM grob)
 116 {
 117   Grob *me = unsmob_grob (grob);
 118
 119   SCM t = me->get_property ("text");
 120   SCM chain = Font_interface::text_font_alist_chain (me);
 121   return interpret_markup (me->layout ()->self_scm (), chain, t);
 122 }
 123
 124 /* Ugh. Duplicated from Scheme.  */
 125 bool
 126 Text_interface::is_markup (SCM x)
 127 {
 128   return (scm_is_string (x)
 129           || (scm_is_pair (x)
 130               && SCM_BOOL_F
 131               != scm_object_property (scm_car (x),
 132                                       ly_symbol2scm ("markup-signature"))));
 133 }
 134
 135 bool
 136 Text_interface::is_markup_list (SCM x)
 137 {
 138   SCM music_list_p = ly_lily_module_constant ("markup-list?");
 139   return scm_is_true (scm_call_1 (music_list_p, x));
 140 }
 141
 142
 143 ADD_INTERFACE (Text_interface,
 144                "A Scheme markup text, see @ruser{Formatting text} and"
 145                " @rextend{New markup command definition}.\n"
 146                "\n"
 147                "There are two important commands:"
 148                " @code{ly:text-interface::print}, which is a"
 149                " grob callback, and"
 150                " @code{ly:text-interface::interpret-markup}.",
 151
 152                /* properties */
 153                "baseline-skip "
 154                "text "
 155                "word-space "
 156                "text-direction "
 157                );
 158