;; TELU-OTF.flt -- Font Layout Table for Telugu OpenType fonts
;; Copyright (C) 2004, 2007, 2008  AIST (H15PRO112)
;; See the end for copying conditions.

(font layouter telu-otf nil
      (font (nil nil unicode-bmp :otf=telu=blwf)))

;;; <li> TELU-OTF.flt
;;;
;;; For Telugu OpenType fonts to draw the Telugu script.

(category
 ;; C: consonant
 ;; H: HALANT
 ;; u: vowel sign (above)
 ;; p: vowel sign (post)
 ;; b: vowel sign (below)
 ;; a: vowel modifier (post)
 ;; V: independent vowel
 ;; N: ZWNJ (ZERO WIDTH NON-JOINER)
 ;; J: ZWJ (ZERO WIDTH JOINER)
 ;; X: generic
 (0x0C00 0x0C7F	?E)			; generic
 (0x0C01 0x0C03	?a)			; SIGN CANDRABINDU .. VISARGA
 (0x0C05 0x0C14	?V)			; LETTER A .. AU
 (0x0C15 0x0C39 ?C)			; LETTER KA .. HA
 (0x0C3E 0x0C40	?u)			; VOWEL SIGN AA .. II
 (0x0C41 0x0C44	?p)			; VOWEL SIGN U .. VOCALIC RR
 (0x0C46 0x0C47	?u)			; VOWEL SIGN E .. EE
 (0x0C4A 0x0C4C	?u)			; VOWEL SIGN O .. AU
 (0x0C4D	?H)			; SIGN VIRAMA
 (0x0C55	?u)			; LENGTH MARK
 (0x0C56	?b)			; AI LENGTH MARK
 (0x0C58 0x0C59 ?C)			; LETTER TSA .. DZA
 (0x0C60 0x0C61	?V)			; LETTER VOCALIC RR .. VOCALIC LL
 (0x0C62 0x0C63 ?b)			; VOWEL SIGN VOCALIC L .. LL
 (0x0964 0x0965	?X)			; DANDA .. DOUBLE DANDA
 (0x200C	?N)			; ZWNJ
 (0x200D	?J)			; ZWJ
 )

;; Decompose two-part vowels.
(generator
 (0
  (cond
   ((0x0C48)
    0x0C46 0x0C56)
   ("." =))
  *))

;; Syllable identification and reordering.  The base consonant is
;; always the first one, because all Telugu consonants have a below
;; form.
(generator
 (0
  (cond
   ;; A syllable with a vowel sign.
   ;;1  23     4      5
   ("(C)((HC)*)(ub?|p)(a)?"
    < | (1 =) (2 move-h) (4 = *) (5 =) | >)

   ;; A syllable with a vowel modifier.
   ;;1  23     4
   ("(C)((HC)*)(a)"
    < | (1 =) (2 move-h) (4 =) | >)

   ;; No vowel signs, no vowel modifiers.  If the syllable ends with a
   ;; Halant, cancel the Halant movement.
   ;;1  23     4
   ("(C)((HC)*)(HN?)?"
    < | (1 =) (4 0x0C4D) (2 move-h) | >)

   ;; A syllable starting with an independent vowel.
   ("Va?"
    < | = * | >)

   ("." =))
  *)

 (move-h
  (cond
   ("(H)(.+)"
    (2 = *) (1 =)))))

;; Apply OTF features.  In case of Telugu, 'akhn' is applied after
;; reordering.
(generator
 (0
  (cond
   ;; A syllable that ends with a Halant.
   (" (CH)([^ ]*) "
    (1 otf:telu=haln+) (2 otf:telu=akhn,blwf,abvs,blws,psts+abvm,blwm,dist))

   ;; Ordinary syllables.
   (" ([^ ]+) "
    (1 otf:telu=akhn,blwf,abvs,blws,psts+absm,blwm,dist))

   ("."
    [ = ]))
  *))

;; Copyright (C) 2004, 2007, 2008
;;   National Institute of Advanced Industrial Science and Technology (AIST)
;;   Registration Number H15PRO112

;; This file is part of the m17n database; a sub-part of the m17n
;; library.

;; The m17n library is free software; you can redistribute it and/or
;; modify it under the terms of the GNU Lesser General Public License
;; as published by the Free Software Foundation; either version 2.1 of
;; the License, or (at your option) any later version.

;; The m17n library is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
;; Lesser General Public License for more details.

;; You should have received a copy of the GNU Lesser General Public
;; License along with the m17n library; if not, write to the Free
;; Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
;; Boston, MA 02110-1301, USA.

;; Local Variables:
;; mode: emacs-lisp
;; End: