lisp/language/indian.el

   1 ;;; indian.el --- Indian languages support -*- coding: iso-2022-7bit; -*-
   2
   3 ;; Copyright (C) 1997, 1999, 2001  Free Software Foundation, Inc.
   4 ;; Copyright (C) 2002, 2003
   5 ;;   National Institute of Advanced Industrial Science and Technology (AIST)
   6 ;;   Registration Number H14PRO021
   7
   8 ;; Maintainer:  KAWABATA, Taichi <kawabata@m17n.org>
   9 ;; Keywords:    multilingual, i18n, Indian
  10
  11 ;; This file is part of GNU Emacs.
  12
  13 ;; GNU Emacs is free software; you can redistribute it and/or modify
  14 ;; it under the terms of the GNU General Public License as published by
  15 ;; the Free Software Foundation; either version 2, or (at your option)
  16 ;; any later version.
  17
  18 ;; GNU Emacs is distributed in the hope that it will be useful,
  19 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  20 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21 ;; GNU General Public License for more details.
  22
  23 ;; You should have received a copy of the GNU General Public License
  24 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  25 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  26 ;; Boston, MA 02111-1307, USA.
  27
  28 ;;; Commentary:
  29
  30 ;; This file defines in-is13194 coding system and relationship between
  31 ;; indian-glyph character-set and various CDAC fonts.
  32
  33 ;;; Code:
  34
  35 (make-coding-system
  36  'in-is13194 2 ?D
  37  "8-bit encoding for ASCII (MSB=0) and IS13194-Devanagari (MSB=1)."
  38  '(ascii indian-is13194 nil nil
  39    nil ascii-eol)
  40  `((safe-chars . ,(let ((table (make-char-table 'safe-chars nil)))
  41                     (set-char-table-range table 'indian-is13194 t)
  42                     (dotimes (i 127)
  43                       (aset table i t)
  44                       (aset table (decode-char 'ucs (+ #x900 i)) t))
  45                     table))
  46    (post-read-conversion . in-is13194-post-read-conversion)
  47    (pre-write-conversion . in-is13194-pre-write-conversion)))
  48
  49 (define-coding-system-alias 'devanagari 'in-is13194)
  50
  51 (defvar indian-font-foundry 'cdac
  52   "Font foundry for Indian characters.
  53 Currently supported foundries are `cdac' and `akruti'.")
  54
  55 (defvar indian-script-language-alist
  56   '((devanagari (hindi sanskrit) nil)
  57     (bengali (bengali assamese) nil)
  58     (gurmukhi (punjabi) nil)
  59     (gujarati (gujarati) nil)
  60     (oriya (oriya) nil)
  61     (tamil (tamil) nil)
  62     (telugu (telugu) nil)
  63     (kannada (kannada) nil)
  64     (malayalam (malayalam) nil))
  65   "Alist of Indian scripts vs the corresponding language list and font foundry.
  66 Each element has this form:
  67
  68   (SCRIPT LANGUAGE-LIST FONT-FOUNDRY)
  69
  70 SCRIPT is one of Indian script names.
  71
  72 LANGUAGE-LIST is a list of Indian langauge names SCRIPT is used for.
  73 The list is in the priority order.
  74
  75 FONT-FOUNDRY is a font foundry representing a group of Indian
  76 fonts.  If the value is nil, the value of `indian-font-foundry'
  77 is used.")
  78
  79 (defconst indian-font-char-index-table
  80   '(                                    ; for which language(s)
  81     ;; CDAC fonts
  82     (#x0000 . cdac:dv-ttsurekh)         ; hindi, etc
  83     (#x0100 . cdac:sd-ttsurekh)         ; sanskrit
  84     (#x0200 . cdac:bn-ttdurga)          ; bengali
  85     (#x0300 . cdac:tm-ttvalluvar)       ; tamil
  86     (#x0400 . cdac:tl-tthemalatha)      ; telugu
  87     (#x0500 . cdac:as-ttdurga)          ; assamese
  88     (#x0600 . cdac:or-ttsarala)         ; oriya
  89     (#x0700 . cdac:kn-ttuma)            ; kannada
  90     (#x0800 . cdac:ml-ttkarthika)       ; malayalam
  91     (#x0900 . cdac:gj-ttavantika)       ; gujarati
  92     (#x0A00 . cdac:pn-ttamar)           ; punjabi
  93
  94     ;; AKRUTI fonts
  95     (#x0B00 . akruti:dev)               ; hindi, etc
  96     (#x0C00 . akruti:bng)               ; bengali
  97     (#x0D00 . akruti:pnj)               ; punjabi
  98     (#x0E00 . akruti:guj)               ; gujarati
  99     (#x0F00 . akruti:ori)               ; oriya
 100     (#x1000 . akruti:tml)               ; tamil
 101     (#x1100 . akruti:tlg)               ; telugu
 102     (#x1200 . akruti:knd)               ; kannada
 103     (#x1300 . akruti:mal)               ; malayalam
 104     )
 105   "Alist of indices of `indian-glyph' character vs Indian font identifiers.
 106 Each element has this form: (INDEX . FONT-IDENTIFIER)
 107
 108 INDEX is an index number of the first character in the charset
 109 `indian-glyph' assigned for glyphs in the font specified by
 110 FONT-IDENTIFIER.  Currently FONT-IDENTIFIERs are defined for CDAC
 111 and AKRUTI font groups.")
 112
 113 (defun indian-font-char (index font-identifier)
 114   "Return character of charset `indian-glyph' made from glyph index INDEX.
 115 FONT-IDENTIFIER is an identifier of an Indian font listed in the
 116 variable `indian-font-char-index-table'.  It specifies which
 117 font INDEX is for."
 118   (if (or (< index 0) (> index 255))
 119       (error "Invalid glyph index: %d" index))
 120   (let ((start (car (rassq font-identifier indian-font-char-index-table))))
 121     (if (not start)
 122         (error "Unknown font identifier: %s" font-identifier))
 123     (setq index (+ start index))
 124     (make-char 'indian-glyph (+ (/ index 96) 32) (+ (% index 96) 32))))
 125
 126 ;; Return a range of characters (cons of min and max character) of the
 127 ;; charset `indian-glyph' for displaying SCRIPT in LANGUAGE by a font
 128 ;; of FOUNDRY.
 129
 130 (defun indian-font-char-range (font-identifier)
 131   (cons (indian-font-char 0 font-identifier)
 132         (indian-font-char 255 font-identifier)))
 133
 134 (defvar indian-script-table
 135   '[
 136     devanagari
 137     sanskrit
 138     bengali
 139     tamil
 140     telugu
 141     assamese
 142     oriya
 143     kannada
 144     malayalam
 145     gujarati
 146     punjabi
 147     ]
 148   "Vector of Indian script names.")
 149
 150 (let ((len (length indian-script-table))
 151       (i 0))
 152   (while (< i len)
 153     (put (aref indian-script-table i) 'indian-glyph-code-offset (* 256 i))
 154     (setq i (1+ i))))
 155
 156 (defvar indian-default-script 'devanagari
 157   "Default script for Indian languages.
 158 Each Indian language environment sets this value
 159 to one of `indian-script-table' (which see).
 160 The default value is `devanagari'.")
 161
 162 (define-ccl-program ccl-encode-indian-glyph-font
 163   `(0
 164     ;; Shorten (r1 = (((((r1 - 32) * 96) + r2) - 32) % 256))
 165     (r1 = ((((r1 * 96) + r2) - ,(+ (* 32 96) 32)) % 256))))
 166
 167 (setq font-ccl-encoder-alist
 168       (cons (cons "-CDAC" 'ccl-encode-indian-glyph-font)
 169             font-ccl-encoder-alist))
 170
 171 (setq font-ccl-encoder-alist
 172       (cons (cons "-AKRUTI" 'ccl-encode-indian-glyph-font)
 173             font-ccl-encoder-alist))
 174
 175 (provide 'indian)
 176
 177 ;;; arch-tag: 83aa8fc7-7ee2-4364-a6e5-498f5e3b8c2f
 178 ;;; indian.el ends here