1;;; indian.el --- Indian languages support -*- coding: iso-2022-7bit; -*-
2
3;; Copyright (C) 1997, 1999, 2001, 2002, 2003, 2004, 2005, 2006, 2007
4;;   Free Software Foundation, Inc.
5;; Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007
6;;   National Institute of Advanced Industrial Science and Technology (AIST)
7;;   Registration Number H14PRO021
8
9;; Maintainer:  KAWABATA, Taichi <kawabata@m17n.org>
10;; Keywords: 	multilingual, i18n, Indian
11
12;; This file is part of GNU Emacs.
13
14;; GNU Emacs is free software; you can redistribute it and/or modify
15;; it under the terms of the GNU General Public License as published by
16;; the Free Software Foundation; either version 2, or (at your option)
17;; any later version.
18
19;; GNU Emacs is distributed in the hope that it will be useful,
20;; but WITHOUT ANY WARRANTY; without even the implied warranty of
21;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
22;; GNU General Public License for more details.
23
24;; You should have received a copy of the GNU General Public License
25;; along with GNU Emacs; see the file COPYING.  If not, write to the
26;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
27;; Boston, MA 02110-1301, USA.
28
29;;; Commentary:
30
31;; This file defines in-is13194 coding system and relationship between
32;; indian-glyph character-set and various CDAC fonts.
33
34;;; Code:
35
36(make-coding-system
37 'in-is13194 2 ?D
38 "8-bit encoding for ASCII (MSB=0) and IS13194-Devanagari (MSB=1)."
39 '(ascii indian-is13194 nil nil
40   nil ascii-eol)
41 `((safe-chars . ,(let ((table (make-char-table 'safe-chars nil)))
42		    (set-char-table-range table 'indian-is13194 t)
43		    (dotimes (i 127)
44		      (aset table i t)
45		      (aset table (decode-char 'ucs (+ #x900 i)) t))
46		    table))
47   (post-read-conversion . in-is13194-post-read-conversion)
48   (pre-write-conversion . in-is13194-pre-write-conversion)))
49
50(define-coding-system-alias 'devanagari 'in-is13194)
51
52(defvar indian-font-foundry 'cdac
53  "Font foundry for Indian characters.
54Currently supported foundries are `cdac' and `akruti'.")
55
56(defvar indian-script-language-alist
57  '((devanagari (hindi sanskrit) nil)
58    (bengali (bengali assamese) nil)
59    (gurmukhi (punjabi) nil)
60    (gujarati (gujarati) nil)
61    (oriya (oriya) nil)
62    (tamil (tamil) nil)
63    (telugu (telugu) nil)
64    (kannada (kannada) nil)
65    (malayalam (malayalam) nil))
66  "Alist of Indian scripts vs the corresponding language list and font foundry.
67Each element has this form:
68
69  (SCRIPT LANGUAGE-LIST FONT-FOUNDRY)
70
71SCRIPT is one of Indian script names.
72
73LANGUAGE-LIST is a list of Indian langauge names SCRIPT is used for.
74The list is in the priority order.
75
76FONT-FOUNDRY is a font foundry representing a group of Indian
77fonts.  If the value is nil, the value of `indian-font-foundry'
78is used.")
79
80(defconst indian-font-char-index-table
81  '(					; for which language(s)
82    ;; CDAC fonts
83    (#x0000 . cdac:dv-ttsurekh)		; hindi, etc
84    (#x0100 . cdac:sd-ttsurekh)		; sanskrit
85    (#x0200 . cdac:bn-ttdurga)		; bengali
86    (#x0300 . cdac:tm-ttvalluvar)	; tamil
87    (#x0400 . cdac:tl-tthemalatha)	; telugu
88    (#x0500 . cdac:as-ttdurga)		; assamese
89    (#x0600 . cdac:or-ttsarala)		; oriya
90    (#x0700 . cdac:kn-ttuma)		; kannada
91    (#x0800 . cdac:ml-ttkarthika)	; malayalam
92    (#x0900 . cdac:gj-ttavantika)	; gujarati
93    (#x0A00 . cdac:pn-ttamar)		; punjabi
94
95    ;; AKRUTI fonts
96    (#x0B00 . akruti:dev)		; hindi, etc
97    (#x0C00 . akruti:bng)		; bengali
98    (#x0D00 . akruti:pnj)		; punjabi
99    (#x0E00 . akruti:guj)		; gujarati
100    (#x0F00 . akruti:ori)		; oriya
101    (#x1000 . akruti:tml)		; tamil
102    (#x1100 . akruti:tlg)		; telugu
103    (#x1200 . akruti:knd)		; kannada
104    (#x1300 . akruti:mal)		; malayalam
105    )
106  "Alist of indices of `indian-glyph' character vs Indian font identifiers.
107Each element has this form: (INDEX . FONT-IDENTIFIER)
108
109INDEX is an index number of the first character in the charset
110`indian-glyph' assigned for glyphs in the font specified by
111FONT-IDENTIFIER.  Currently FONT-IDENTIFIERs are defined for CDAC
112and AKRUTI font groups.")
113
114(defun indian-font-char (index font-identifier)
115  "Return character of charset `indian-glyph' made from glyph index INDEX.
116FONT-IDENTIFIER is an identifier of an Indian font listed in the
117variable `indian-font-char-index-table'.  It specifies which
118font INDEX is for."
119  (if (or (< index 0) (> index 255))
120      (error "Invalid glyph index: %d" index))
121  (let ((start (car (rassq font-identifier indian-font-char-index-table))))
122    (if (not start)
123	(error "Unknown font identifier: %s" font-identifier))
124    (setq index (+ start index))
125    (make-char 'indian-glyph (+ (/ index 96) 32) (+ (% index 96) 32))))
126
127;; Return a range of characters (cons of min and max character) of the
128;; charset `indian-glyph' for displaying SCRIPT in LANGUAGE by a font
129;; of FOUNDRY.
130
131(defun indian-font-char-range (font-identifier)
132  (cons (indian-font-char 0 font-identifier)
133	(indian-font-char 255 font-identifier)))
134
135(defvar indian-script-table
136  '[
137    devanagari
138    sanskrit
139    bengali
140    tamil
141    telugu
142    assamese
143    oriya
144    kannada
145    malayalam
146    gujarati
147    punjabi
148    ]
149  "Vector of Indian script names.")
150
151(let ((len (length indian-script-table))
152      (i 0))
153  (while (< i len)
154    (put (aref indian-script-table i) 'indian-glyph-code-offset (* 256 i))
155    (setq i (1+ i))))
156
157(defvar indian-default-script 'devanagari
158  "Default script for Indian languages.
159Each Indian language environment sets this value
160to one of `indian-script-table' (which see).
161The default value is `devanagari'.")
162
163(define-ccl-program ccl-encode-indian-glyph-font
164  `(0
165    ;; Shorten (r1 = (((((r1 - 32) * 96) + r2) - 32) % 256))
166    (r1 = ((((r1 * 96) + r2) - ,(+ (* 32 96) 32)) % 256))))
167
168(setq font-ccl-encoder-alist
169      (cons (cons "-CDAC" 'ccl-encode-indian-glyph-font)
170	    font-ccl-encoder-alist))
171
172(setq font-ccl-encoder-alist
173      (cons (cons "-AKRUTI" 'ccl-encode-indian-glyph-font)
174	    font-ccl-encoder-alist))
175
176(provide 'indian)
177
178;;; arch-tag: 83aa8fc7-7ee2-4364-a6e5-498f5e3b8c2f
179;;; indian.el ends here
180