diff options
Diffstat (limited to 'lisp/language/misc-lang.el')
| -rw-r--r-- | lisp/language/misc-lang.el | 195 |
1 files changed, 191 insertions, 4 deletions
diff --git a/lisp/language/misc-lang.el b/lisp/language/misc-lang.el index 2843c7c9038..3d5b68f84be 100644 --- a/lisp/language/misc-lang.el +++ b/lisp/language/misc-lang.el @@ -1,5 +1,6 @@ -;;; misc-lang.el --- support for miscellaneous languages (characters) +;;; misc-lang.el --- support for miscellaneous languages (characters) -*- lexical-binding: t; -*- +;; Copyright (C) 2012-2022 Free Software Foundation, Inc. ;; Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, ;; 2005, 2006, 2007, 2008, 2009, 2010, 2011 ;; National Institute of Advanced Industrial Science and Technology (AIST) @@ -75,12 +76,198 @@ and Italian."))) (sample-text . "Persian فارسی") (documentation . "Bidirectional editing is supported."))) +(defcustom arabic-shaper-ZWNJ-handling nil + "How to handle ZWMJ in Arabic text rendering. +This variable controls the way to handle a glyph for ZWNJ +returned by the underling shaping engine. + +The default value is nil, which means that the ZWNJ glyph is +displayed as is. + +If the value is `absorb', ZWNJ is absorbed into the previous +grapheme cluster, and not displayed. + +If the value is `as-space', the glyph is displayed by a +thin (i.e. 1-dot width) space." + :group 'mule + :version "26.1" + :type '(choice + (const :tag "default" nil) + (const :tag "as space" as-space) + (const :tag "absorb" absorb)) + :set (lambda (sym val) + (set-default sym val) + (clear-composition-cache))) + +;; Record error in arabic-change-gstring. +(defvar arabic-shape-log nil) + +(defun arabic-shape-gstring (gstring direction) + (setq gstring (font-shape-gstring gstring direction)) + (condition-case err + (when arabic-shaper-ZWNJ-handling + (let ((font (lgstring-font gstring)) + (i 1) + (len (lgstring-glyph-len gstring)) + (modified nil)) + (while (< i len) + (let ((glyph (lgstring-glyph gstring i))) + (when (eq (lglyph-char glyph) #x200c) + (cond + ((eq arabic-shaper-ZWNJ-handling 'as-space) + (if (> (- (lglyph-rbearing glyph) (lglyph-lbearing glyph)) 0) + (let ((space-glyph (aref (font-get-glyphs font 0 1 " ") 0))) + (when space-glyph + (lglyph-set-code glyph (aref space-glyph 3)) + (lglyph-set-width glyph (aref space-glyph 4))))) + (lglyph-set-adjustment glyph 0 0 1) + (setq modified t)) + ((eq arabic-shaper-ZWNJ-handling 'absorb) + (let ((prev (lgstring-glyph gstring (1- i)))) + (lglyph-set-from-to prev (lglyph-from prev) (lglyph-to glyph)) + (setq gstring (lgstring-remove-glyph gstring i)) + (setq len (1- len))) + (setq modified t))))) + (setq i (1+ i))) + (if modified + (lgstring-set-id gstring nil)))) + (error (push err arabic-shape-log))) + gstring) + (set-char-table-range composition-function-table '(#x600 . #x74F) - (list (vector "[\u0600-\u074F\u200C\u200D]+" 0 'font-shape-gstring) - (vector "[\u200C\u200D][\u0600-\u074F\u200C\u200D]+" - 1 'font-shape-gstring))) + (list (vector "[\u0600-\u074F\u200C\u200D]+" + 0 #'arabic-shape-gstring))) +(set-char-table-range + composition-function-table + '(#x200C . #x200D) + (list (vector "[\u200C\u200D][\u0600-\u074F\u200C\u200D]+" + 0 #'arabic-shape-gstring))) + +;; The Egyptian Hieroglyph Format Controls were introduced in Unicode +;; Standard v12.0. Apparently, they are not yet well supported in +;; existing fonts, as of late 2020. But there's no reason for us not +;; to be ready for when they will be! +;; The below is needed to support the arrangement of the Egyptian +;; Hieroglyphs in "quadrats", as directed by the format controls, +;; which specify how the hieroglyphs should be joined horizontally and +;; vertically. +(defun egyptian-shape-grouping (gstring direction) + (if (= (lgstring-char gstring 0) #x13437) + (let ((nchars (lgstring-char-len gstring)) + (i 1) + (nesting 1) + ch) + ;; Find where this group ends. + (while (and (< i nchars) (> nesting 0)) + (setq ch (lgstring-char gstring i)) + (cond + ((= ch #x13437) + (setq nesting (1+ nesting))) + ((= ch #x13438) + (setq nesting (1- nesting)))) + (setq i (1+ i))) + (when (zerop nesting) + ;; Make a new gstring from the characters that constitute a + ;; complete nested group. + (let ((new-header (make-vector (1+ i) nil)) + (new-gstring (make-vector (+ i 2) nil))) + (aset new-header 0 (lgstring-font gstring)) + (dotimes (j i) + (aset new-header (1+ j) (lgstring-char gstring j)) + (lgstring-set-glyph new-gstring j (lgstring-glyph gstring j))) + (lgstring-set-header new-gstring new-header) + (font-shape-gstring new-gstring direction)))))) + +(let ((hieroglyph "[\U00013000-\U0001342F]")) + ;; HORIZONTAL/VERTICAL JOINER and INSERT AT.../OVERLAY controls + (set-char-table-range + composition-function-table + '(#x13430 . #x13436) + (list (vector (concat hieroglyph "[\U00013430-\U00013436]" hieroglyph) + ;; We use font-shape-gstring so that, if the font + ;; doesn't support these controls, the glyphs are + ;; displayed individually, and not as a single + ;; grapheme cluster. + 1 #'font-shape-gstring))) + ;; Grouping controls + (set-char-table-range + composition-function-table + #x13437 + (list (vector "\U00013437[\U00013000-\U0001343F]+" + 0 #'egyptian-shape-grouping))) + ;; "Normal" hieroglyphs, for fonts that don't support the above + ;; controls, but do shape sequences of hieroglyphs without the + ;; controls. + ;; FIXME: As of late 2021, Egyptian Hieroglyph Format Controls are + ;; not yet supported in existing fonts and/or shaping engines, but + ;; some fonts do provide ligatures with which texts in Egyptian + ;; Hieroglyphs are correctly displayed. If and when these format + ;; controls are supported, as described in section 11.4 "Egyptian + ;; Hieroglyphs" of the Unicode Standard, the five lines below (which + ;; allow composition of hieroglyphs without formatting controls + ;; around) can be removed, and the entry in etc/HELLO can be + ;; restored to: + ;; Egyptian Hieroglyphs (𓂋𓏤𓈖𓆎𓅓𓏏𓊖) 𓅓𓊵𓏏𓊪, 𓇍𓇋𓂻𓍘𓇋 + (set-char-table-range + composition-function-table + '(#x13000 . #x1342E) + (list (vector "[\U00013000-\U0001342E]+" + 0 #'font-shape-gstring)))) + +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; +;; Hanifi Rohingya +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; + +(set-language-info-alist + "Hanifi Rohingya" '((charset unicode) + (coding-system utf-8) + (coding-priority utf-8) + (input-method . "hanifi-rohingya") + (sample-text . "Hanifi Rohingya (𐴌𐴟𐴇𐴥𐴝𐴚𐴒𐴙𐴝 𐴇𐴝𐴕𐴞𐴉𐴞 𐴓𐴠𐴑𐴤𐴝) 𐴀𐴝𐴏𐴓𐴝𐴀𐴡𐴤𐴛𐴝𐴓𐴝𐴙𐴑𐴟𐴔") + (documentation . "\ +Rohingya language and its script Hanifi Rohingya are supported +in this language environment."))) + +;; Hanifi Rohingya composition rules +(set-char-table-range + composition-function-table + '(#x10D1D . #x10D27) + (list (vector + "[\x10D00-\x10D27]+" + 1 'font-shape-gstring))) + +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; +;; Kharoṣṭhī +;; Author: Stefan Baums <baums@gandhari.org> +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; + +(set-language-info-alist + "Kharoshthi" '((charset unicode) + (coding-system utf-8) + (coding-priority utf-8) + (input-method . "kharoshthi") + (sample-text . "Kharoṣṭhī (𐨑𐨪𐨆𐨛𐨁) 𐨣𐨨𐨲𐨪𐨆 𐨐𐨪𐨅𐨨𐨁") + (documentation . "\ +Language environment for Gāndhārī, Sanskrit, and other languages +using the Kharoṣṭhī script."))) + +(let ((consonant "[\U00010A00\U00010A10-\U00010A35]") + (vowel "[\U00010A01-\U00010A06]") + (virama "\U00010A3F") + (modifier "[\U00010A0C-\U00010A0F\U00010A38-\U00010A3A]")) + (set-char-table-range composition-function-table + '(#x10A3F . #x10A3F) + (list + (vector + (concat consonant + "\\(?:" virama consonant "\\)*" + modifier "*" + virama "?" + vowel "*" + modifier "*") + 1 'font-shape-gstring)))) (provide 'misc-lang) |