Improve support for the Brahmi script

* lisp/language/indian.el ("Brahmi"): New language environment.
Add composition rules for Brahmi.
* lisp/international/fontset.el (script-representative-chars)
(setup-default-fontset): Support Brahmi.  (Bug#54914)

* etc/NEWS: Announce the new language environment.

1 files changed, 34 insertions, 0 deletions

diff --git a/lisp/language/indian.el b/lisp/language/indian.el
index e0adb0de6c3..310905534e6 100644
--- a/lisp/language/indian.el
+++ b/lisp/language/indian.el
@@ -126,6 +126,16 @@ environment."))
 South Indian language Malayalam is supported in this language environment."))
  '("Indian"))
 
+(set-language-info-alist
+ "Brahmi" '((charset unicode)
+	    (coding-system utf-8)
+	    (coding-priority utf-8)
+	    ; (input-method . "brahmi") ; FIXME
+	    (documentation . "\
+The ancient Brahmi script is supported in this language environment."))
+ '("Indian"))                           ; Should we have an "Old" category?
+
+
 ;; Replace mnemonic characters in REGEXP according to TABLE.  TABLE is
 ;; an alist of (MNEMONIC-STRING . REPLACEMENT-STRING).
 
@@ -384,6 +394,30 @@ South Indian language Malayalam is supported in this language environment."))
 	      (list (vector (cdr slot) 0 #'font-shape-gstring))))))
    char-script-table))
 
+;; Brahmi composition rules
+(let ((consonant     "[\U00011013-\U00011034]")
+      (non-consonant "[^\U00011013-\U00011034]")
+      (numeral       "[\U00011052-\U00011065]")
+      (multiplier    "[\U00011064\U00011065]")
+      (virama        "\U00011046")
+      (number-joiner "\U0001107F"))
+  (set-char-table-range composition-function-table
+		        '(#x11046 . #x11046)
+                        (list (vector
+                               ;; Consonant conjuncts
+                               (concat consonant virama consonant)
+                               1 'font-shape-gstring)
+                              (vector
+                               ;; Vowelless consonants
+                               (concat consonant virama non-consonant)
+                               1 'font-shape-gstring)))
+  (set-char-table-range composition-function-table
+                        '(#x1107F . #x1107F)
+                        (list (vector
+                               ;; Additive-multiplicative numerals
+                               (concat multiplier number-joiner numeral)
+                               1 'font-shape-gstring))))
+
 (provide 'indian)
 
 ;;; indian.el ends here