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
  13 #include "main.hh"
  14 #include "config.hh"
  15 #include "pango-font.hh"
  16 #include "warn.hh"
  17 #include "grob.hh"
  18 #include "font-interface.hh"
  19 #include "output-def.hh"
  20 #include "modified-font-metric.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       vsize char_len = 1;
  31       char cur = (*str)[i];
  32
  33       // U+10000 - U+10FFFF
  34       if ((cur & 0x11110000) == 0x11110000)
  35         char_len = 4;
  36       // U+0800 - U+FFFF
  37       else if ((cur & 0x11100000) == 0x11100000)
  38         char_len = 3;
  39       // U+0080 - U+07FF
  40       else if ((cur & 0x11000000) == 0x11000000)
  41         char_len = 2;
  42       else if (cur & 0x10000000)
  43         programming_error ("invalid utf-8 string");
  44       else
  45         // avoid the locale-dependent isspace
  46         if (cur == '\n' || cur == '\t' || cur == '\v')
  47           (*str)[i] = ' ';
  48
  49       i += char_len;
  50     }
  51 }
  52
  53 MAKE_SCHEME_CALLBACK (Text_interface, interpret_string, 3);
  54 SCM
  55 Text_interface::interpret_string (SCM layout_smob,
  56                                   SCM props,
  57                                   SCM markup)
  58 {
  59   LY_ASSERT_SMOB (Output_def, layout_smob, 1);
  60   LY_ASSERT_TYPE (scm_is_string, markup, 3);
  61
  62   string str = ly_scm2string (markup);
  63   Output_def *layout = unsmob_output_def (layout_smob);
  64   Font_metric *fm = select_encoded_font (layout, props);
  65
  66   replace_whitespace (&str);
  67   return fm->word_stencil (str).smobbed_copy ();
  68 }
  69
  70 MAKE_SCHEME_CALLBACK_WITH_OPTARGS (Text_interface, interpret_markup, 3, 0,
  71                                    "Convert a text markup into a stencil."
  72 "  Takes three arguments, @var{layout}, @var{props}, and @var{markup}.\n"
  73 "\n"
  74 "@var{layout} is a @code{\\layout} block; it may be obtained from a grob with"
  75 " @code{ly:grob-layout}.  @var{props} is an alist chain, i.e. a list of"
  76 "  alists.  This is typically obtained with"
  77 " @code{(ly:grob-alist-chain grob (ly:output-def-lookup layout 'text-font-defaults))}."
  78 "  @var{markup} is the markup text to be processed.");
  79 SCM
  80 Text_interface::interpret_markup (SCM layout_smob, SCM props, SCM markup)
  81 {
  82   if (scm_is_string (markup))
  83     return interpret_string (layout_smob, props, markup);
  84   else if (scm_is_pair (markup))
  85     {
  86       SCM func = scm_car (markup);
  87       SCM args = scm_cdr (markup);
  88       if (!is_markup (markup))
  89         programming_error ("markup head has no markup signature");
  90
  91       return scm_apply_2 (func, layout_smob, props, args);
  92     }
  93   else
  94     {
  95       programming_error ("Object is not a markup. ");
  96       scm_puts ("This object should be a markup: ", scm_current_error_port ());
  97       scm_display (markup, scm_current_error_port ());
  98       scm_puts ("\n", scm_current_error_port ());
  99
 100       Box b;
 101       b[X_AXIS].set_empty ();
 102       b[Y_AXIS].set_empty ();
 103
 104       Stencil s (b, SCM_EOL);
 105       return s.smobbed_copy ();
 106     }
 107 }
 108
 109 MAKE_SCHEME_CALLBACK (Text_interface, print, 1);
 110 SCM
 111 Text_interface::print (SCM grob)
 112 {
 113   Grob *me = unsmob_grob (grob);
 114
 115   SCM t = me->get_property ("text");
 116   SCM chain = Font_interface::text_font_alist_chain (me);
 117   return interpret_markup (me->layout ()->self_scm (), chain, t);
 118 }
 119
 120 /* Ugh. Duplicated from Scheme.  */
 121 bool
 122 Text_interface::is_markup (SCM x)
 123 {
 124   return (scm_is_string (x)
 125           || (scm_is_pair (x)
 126               && SCM_BOOL_F
 127               != scm_object_property (scm_car (x),
 128                                       ly_symbol2scm ("markup-signature"))));
 129 }
 130
 131 bool
 132 Text_interface::is_markup_list (SCM x)
 133 {
 134   SCM music_list_p = ly_lily_module_constant ("markup-list?");
 135   return scm_is_true (scm_call_1 (music_list_p, x));
 136 }
 137
 138
 139 ADD_INTERFACE (Text_interface,
 140                "A Scheme markup text, see @ruser{Formatting text} and"
 141                " @ruser{New markup command definition}.\n"
 142                "\n"
 143                "There are two important commands:"
 144                " @code{ly:text-interface::print}, which is a"
 145                " grob callback, and"
 146                " @code{ly:text-interface::interpret-markup}.",
 147
 148                /* properties */
 149                "baseline-skip "
 150                "text "
 151                "word-space "
 152                "text-direction "
 153                );
 154