X-Git-Url: https://git.hcoop.net/bpt/emacs.git/blobdiff_plain/3f715d17fef56ee78a3df7ebb00d4e8b1aec37de..b0126eac41487b9bca5af5cbb2212ff5b2c58b80:/lisp/language/hebrew.el

diff --git a/lisp/language/hebrew.el b/lisp/language/hebrew.el
index 50c0a243d2..24ddfb2c11 100644
--- a/lisp/language/hebrew.el
+++ b/lisp/language/hebrew.el
@@ -1,9 +1,9 @@
-;;; hebrew.el --- support for Hebrew -*- coding: iso-2022-7bit; no-byte-compile: t -*-
+;;; hebrew.el --- support for Hebrew -*- coding: utf-8 -*-
 
-;; Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
+;; Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
 ;;   Free Software Foundation, Inc.
 ;; Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
-;;   2005, 2006, 2007, 2008
+;;   2005, 2006, 2007, 2008, 2009, 2010
 ;;   National Institute of Advanced Industrial Science and Technology (AIST)
 ;;   Registration Number H14PRO021
 
@@ -46,28 +46,27 @@
 (define-coding-system-alias 'iso-8859-8 'hebrew-iso-8bit)
 
 ;; These are for Explicit and Implicit directionality information, as
-;; defined in RFC 1556.  We don't yet support directional information
-;; in bidi languages, so these aliases are a lie, especially as far as
-;; iso-8859-8-e is concerned.  FIXME.
+;; defined in RFC 1556.
 (define-coding-system-alias 'iso-8859-8-e 'hebrew-iso-8bit)
 (define-coding-system-alias 'iso-8859-8-i 'hebrew-iso-8bit)
 
 (set-language-info-alist
- "Hebrew" '((charset iso-8859-8)
+ "Hebrew" '((tutorial . "TUTORIAL.he")
+	    (charset iso-8859-8)
 	    (coding-priority hebrew-iso-8bit)
 	    (coding-system hebrew-iso-8bit windows-1255 cp862)
 	    (nonascii-translation . iso-8859-8)
 	    (input-method . "hebrew")
 	    (unibyte-display . hebrew-iso-8bit)
-	    (sample-text . "Hebrew	,Hylem(B")
-	    (documentation . "Right-to-left writing is not yet supported.")))
+	    (sample-text . "Hebrew	שלום")
+	    (documentation . "Bidirectional editing is supported.")))
 
 (set-language-info-alist
  "Windows-1255" '((coding-priority windows-1255)
 		  (coding-system windows-1255)
 		  (documentation . "\
 Support for Windows-1255 encoding, e.g. for Yiddish.
-Right-to-left writing is not yet supported.")))
+Bidirectional editing is supported.")))
 
 (define-coding-system 'windows-1255
   "windows-1255 (Hebrew) encoding (MIME: WINDOWS-1255)"
@@ -85,6 +84,179 @@ Right-to-left writing is not yet supported.")))
   :mime-charset 'cp862)
 (define-coding-system-alias 'ibm862 'cp862)
 
+;; Return a nested alist of Hebrew character sequences vs the
+;; corresponding glyph of FONT-OBJECT.
+(defun hebrew-font-get-precomposed (font-object)
+  (let ((precomposed (font-get font-object 'hebrew-precomposed))
+	;; Vector of Hebrew precomposed charaters.
+	(chars [#xFB2A #xFB2B #xFB2C #xFB2D #xFB2E #xFB2F #xFB30 #xFB31
+		#xFB32 #xFB33 #xFB34 #xFB35 #xFB36 #xFB38 #xFB39 #xFB3A
+		#xFB3B #xFB3C #xFB3E #xFB40 #xFB41 #xFB43 #xFB44 #xFB46
+		#xFB47 #xFB48 #xFB49 #xFB4A #xFB4B #xFB4C #xFB4D #xFB4E])
+	;; Vector of decomposition character sequences corresponding
+	;; to the above vector.
+	(decomposed 
+	 [[#x05E9 #x05C1]
+	  [#x05E9 #x05C2]
+	  [#x05E9 #x05BC #x05C1]
+	  [#x05E9 #x05BC #x05C2]
+	  [#x05D0 #x05B7]
+	  [#x05D0 #x05B8]
+	  [#x05D0 #x05BC]
+	  [#x05D1 #x05BC]
+	  [#x05D2 #x05BC]
+	  [#x05D3 #x05BC]
+	  [#x05D4 #x05BC]
+	  [#x05D5 #x05BC]
+	  [#x05D6 #x05BC]
+	  [#x05D8 #x05BC]
+	  [#x05D9 #x05BC]
+	  [#x05DA #x05BC]
+	  [#x05DB #x05BC]
+	  [#x05DC #x05BC]
+	  [#x05DE #x05BC]
+	  [#x05E0 #x05BC]
+	  [#x05E1 #x05BC]
+	  [#x05E3 #x05BC]
+	  [#x05E4 #x05BC]
+	  [#x05E6 #x05BC]
+	  [#x05E7 #x05BC]
+	  [#x05E8 #x05BC]
+	  [#x05E9 #x05BC]
+	  [#x05EA #x05BC]
+	  [#x05D5 #x05B9]
+	  [#x05D1 #x05BF]
+	  [#x05DB #x05BF]
+	  [#x05E4 #x05BF]]))
+    (unless precomposed
+      (setq precomposed (list t))
+      (let ((gvec (font-get-glyphs font-object 0 (length chars) chars)))
+	(dotimes (i (length chars))
+	  (if (aref gvec i)
+	      (set-nested-alist (aref decomposed i) (aref gvec i)
+				precomposed))))
+      ;; Cache the result in FONT-OBJECT's property.
+      (font-put font-object 'hebrew-precomposed precomposed))
+    precomposed))
+
+;; Composition function for hebrew.  GSTRING is made of a Hebrew base
+;; character followed by Hebrew diacritical marks, or is made of
+;; single Hebrew diacritical mark.  Adjust GSTRING to display that
+;; sequence properly.  The basic strategy is:
+;;
+;; (1) If there's single diacritical, add padding space to the left
+;; and right of the glyph.
+;;
+;; (2) If the font has OpenType features for Hebrew, ask the OTF
+;; driver the whole work.
+;;
+;; (3) If the font has precomposed glyphs, use them as far as
+;; possible.  Adjust the remaining glyphs artificially.
+
+(defun hebrew-shape-gstring (gstring)
+  (let* ((font (lgstring-font gstring))
+	 (otf (font-get font :otf))
+	 (nchars (lgstring-char-len gstring))
+	 header nglyphs base-width glyph precomposed val idx)
+    (cond
+     ((= nchars 1)
+      ;; Independent diacritical mark.  Add padding space to left or
+      ;; right so that the glyph doesn't overlap with the surrounding
+      ;; chars.
+      (setq glyph (lgstring-glyph gstring 0))
+      (let ((width (lglyph-width glyph))
+	    bearing)
+	(if (< (setq bearing (lglyph-lbearing glyph)) 0)
+	    (lglyph-set-adjustment glyph bearing 0 (- width bearing)))
+	(if (> (setq bearing (lglyph-rbearing glyph)) width)
+	    (lglyph-set-adjustment glyph 0 0 bearing))))
+
+     ((or (assq 'hebr (car otf)) (assq 'hebr (cdr otf)))
+      ;; FONT has OpenType features for Hebrew.
+      (font-shape-gstring gstring))
+
+     (t
+      ;; FONT doesn't have OpenType features for Hebrew.
+      ;; Try a precomposed glyph.
+      ;; Now GSTRING is in this form:
+      ;;   [[FONT CHAR1 CHAR2 ... CHARn] nil GLYPH1 GLYPH2 ... GLYPHn nil ...]
+      (setq precomposed (hebrew-font-get-precomposed font)
+	    header (lgstring-header gstring)
+	    val (lookup-nested-alist header precomposed nil 1))
+      (if (and (consp val) (vectorp (car val)))
+	  ;; All characters can be displayed by a single precomposed glyph.
+	  ;; Reform GSTRING to [HEADER nil PRECOMPOSED-GLYPH nil ...]
+	  (let ((glyph (copy-sequence (car val))))
+	    (lglyph-set-from-to glyph 0 (1- nchars))
+	    (lgstring-set-glyph gstring 0 glyph)
+	    (lgstring-set-glyph gstring 1 nil))
+	(if (and (integerp val) (> val 2)
+		 (setq glyph (lookup-nested-alist header precomposed val 1))
+		 (consp glyph) (vectorp (car glyph)))
+	    ;; The first (1- VAL) characters can be displayed by a
+	    ;; precomposed glyph.  Provided that VAL is 3, the first
+	    ;; two glyphs should be replaced by the precomposed glyph.
+	    ;; In that case, reform GSTRING to:
+	    ;;   [HEADER nil PRECOMPOSED-GLYPH GLYPH3 ... GLYPHn nil ...]
+	    (let* ((ncmp (1- val))	; number of composed glyphs
+		   (diff (1- ncmp)))	; number of reduced glyphs
+	      (setq glyph (copy-sequence (car glyph)))
+	      (lglyph-set-from-to glyph 0 (1- nchars))
+	      (lgstring-set-glyph gstring 0 glyph)
+	      (setq idx ncmp)
+	      (while (< idx nchars)
+		(setq glyph (lgstring-glyph gstring idx))
+		(lglyph-set-from-to glyph 0 (1- nchars))
+		(lgstring-set-glyph gstring (- idx diff) glyph)
+		(setq idx (1+ idx)))
+	      (lgstring-set-glyph gstring (- idx diff) nil)
+	      (setq idx (- ncmp diff)
+		    nglyphs (- nchars diff)))
+	  (setq glyph (lgstring-glyph gstring 0))
+	  (lglyph-set-from-to glyph 0 (1- nchars))
+	  (setq idx 1 nglyphs nchars))
+	;; Now IDX is an index to the first non-precomposed glyph.
+	;; Adjust positions of the remaining glyphs artificially.
+	(setq base-width (lglyph-width (lgstring-glyph gstring 0)))
+	(while (< idx nglyphs)
+	  (setq glyph (lgstring-glyph gstring idx))
+	  (lglyph-set-from-to glyph 0 (1- nchars))
+	  (if (>= (lglyph-lbearing glyph) (lglyph-width glyph))
+	      ;; It seems that this glyph is designed to be rendered
+	      ;; before the base glyph.
+	      (lglyph-set-adjustment glyph (- base-width) 0 0)
+	    (if (>= (lglyph-lbearing glyph) 0)
+		;; Align the horizontal center of this glyph to the
+		;; horizontal center of the base glyph.
+		(let ((width (- (lglyph-rbearing glyph)
+				(lglyph-lbearing glyph))))
+		  (lglyph-set-adjustment glyph
+					 (- (/ (- base-width width) 2)
+					    (lglyph-lbearing glyph)
+					    base-width) 0 0))))
+	  (setq idx (1+ idx))))))
+    gstring))
+
+(let* ((base "[\u05D0-\u05F2]")
+       (combining "[\u0591-\u05BD\u05BF\u05C1-\u05C2\u05C4-\u05C5\u05C7]+")
+       (pattern1 (concat base combining))
+       (pattern2 (concat base "\u200D" combining)))
+  (set-char-table-range
+   composition-function-table '(#x591 . #x5C7)
+   (list (vector pattern2 3 'hebrew-shape-gstring)
+	 (vector pattern2 2 'hebrew-shape-gstring)
+	 (vector pattern1 1 'hebrew-shape-gstring)
+	 [nil 0 hebrew-shape-gstring]))
+  ;; Exclude non-combining characters.
+  (set-char-table-range
+   composition-function-table #x5BE nil)
+  (set-char-table-range
+   composition-function-table #x5C0 nil)
+  (set-char-table-range
+   composition-function-table #x5C3 nil)
+  (set-char-table-range
+   composition-function-table #x5C6 nil))
+
 (provide 'hebrew)
 
 ;; arch-tag: 3ca04f32-3f1e-498e-af46-8267498ba5d9