lib/ps-utf8.h

   1 /* Dia -- an diagram creation/manipulation program
   2  * Copyright (C) 1998 Alexander Larsson
   3  *
   4  * ps-utf8.h: builds custom Postscript encodings to write arbitrary utf8
   5  * strings and have the device understand what's going on.
   6  * Copyright (C) 2001 Cyrille Chepelov <chepelov@calixo.net>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  21  */
  22
  23 #ifndef PS_UTF8_H
  24 #define PS_UTF8_H
  25
  26 #include <config.h>
  27 #include <glib.h>
  28
  29 #include "diatypes.h"
  30
  31 #define PSEPAGE_BEGIN 32
  32 #define PSEPAGE_SIZE (256-PSEPAGE_BEGIN)
  33
  34 struct _PSFontDescriptor {
  35   const gchar *face; /* LE */
  36   const gchar *name; /* LE */
  37   const PSEncodingPage *encoding; /* DNLE */
  38   int encoding_serial_num; /* if encoding->serial_num > this, we have to
  39                               re-emit the font. If it's negative,
  40                               the font has never been emitted. */
  41 };
  42
  43 /* "defined_fonts" cache is simply a dictionary (g_hash_table):
  44        ("face-e%d-%f" % (encoding_page_#,size)) --> font descriptor
  45
  46 */
  47
  48 struct _PSEncodingPage {
  49   const gchar *name; /* LE. */
  50   int page_num;
  51   int serial_num;
  52   int last_realized;
  53   int entries;
  54   GHashTable *backpage; /* LE(unichar -> char) */
  55   gunichar page[PSEPAGE_SIZE];
  56 };
  57
  58 struct _PSUnicoder {
  59   gpointer usrdata;
  60   const PSUnicoderCallbacks *callbacks;
  61
  62   const gchar *face;
  63   float size;
  64   float current_size; /* might lag a little... */
  65   PSFontDescriptor *current_font; /* DNLE */
  66
  67   GHashTable *defined_fonts;   /* LE(DNLE name -> LE PSFontDescriptor *fd) */
  68   GHashTable *unicode_to_page; /* LE(unicode -> DNLE PSEncodingPage *ep) */
  69   GSList *encoding_pages;      /* LE(LE PSEncodingPage) */
  70   PSEncodingPage *last_page;   /* DNLE */
  71   const PSEncodingPage *current_encoding; /* DNLE */
  72 };
  73
  74 typedef void (*DestroyPSFontFunc)(gpointer usrdata, const gchar *fontname);
  75 typedef void (*BuildPSEncodingFunc)(gpointer usrdata,
  76                                     const gchar *name,
  77                                     const gunichar table[PSEPAGE_SIZE]);
  78 /* note: the first $PSEPAGE_BEGIN will always be /.notdef, likewise
  79    for ( and ) */
  80 typedef void (*BuildPSFontFunc)(gpointer usrdata,
  81                                 const gchar *name,
  82                                 const gchar *face,
  83                                 const gchar *encoding_name);
  84 /* must definefont a font under "fontname", with the "encname" encoding
  85    (already defined). */
  86 typedef void (*SelectPSFontFunc)(gpointer usrdata,
  87                                  const gchar *fontname,
  88                                  float size);
  89 /* must select (setfont) an already found and defined font. */
  90 typedef void (*ShowStringFunc)(gpointer usrdata, const gchar *string);
  91 /* typically, does "(string) show" (but can do other things).
  92    string is guaranteed to not have escaping issues. */
  93 typedef void (*GetStringWidthFunc)(gpointer usrdata, const gchar *string,
  94                                gboolean first);
  95 /* gets the string width on the PS stack. if !first, adds it to the previous
  96    element of the stack. */
  97
  98 struct _PSUnicoderCallbacks {
  99   DestroyPSFontFunc destroy_ps_font;
 100   BuildPSEncodingFunc build_ps_encoding;
 101   BuildPSFontFunc build_ps_font;
 102   SelectPSFontFunc select_ps_font;
 103   ShowStringFunc show_string;
 104   GetStringWidthFunc get_string_width;
 105 };
 106
 107
 108 extern PSUnicoder *ps_unicoder_new(const PSUnicoderCallbacks *psucbk,
 109                                    gpointer usrdata);
 110 extern void ps_unicoder_destroy(PSUnicoder *psu);
 111
 112 extern void psu_set_font_face(PSUnicoder *psu, const gchar *face, float size);
 113 /* just stores the font face and size we'll later use */
 114
 115 extern void psu_check_string_encodings(PSUnicoder *psu,
 116                                        const char *utf8_string);
 117 /* appends what's going to be needed in the encoding tables */
 118
 119 extern void psu_show_string(PSUnicoder *psu,
 120                            const char *utf8_string);
 121 /* shows the string, asking back for as many font and encoding manipulations
 122    as necessary. */
 123 extern void psu_get_string_width(PSUnicoder *psu,
 124                                  const char *utf8_string);
 125 /* puts the string width on the PS stack. */
 126
 127 extern const char *unicode_to_ps_name(gunichar val);
 128 /* returns "uni1234", or a special Adobe entity name. */
 129
 130
 131 #endif /* !PS_UTF8_H */
 132
 133