X-Git-Url: https://code.delx.au/gnu-emacs/blobdiff_plain/771f48f0638f4832c882b2eab1bbc11e36ed5cf5..2988341a84f6e5faef7e5f5ce2c55142935d0fee:/lisp/composite.el diff --git a/lisp/composite.el b/lisp/composite.el index a2457ab751..effa8d6d0a 100644 --- a/lisp/composite.el +++ b/lisp/composite.el @@ -1,6 +1,7 @@ ;;; composite.el --- support character composition -;; Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 +;; Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, +;; 2008, 2009 ;; National Institute of Advanced Industrial Science and Technology (AIST) ;; Registration Number H14PRO021 @@ -8,10 +9,10 @@ ;; This file is part of GNU Emacs. -;; GNU Emacs is free software; you can redistribute it and/or modify +;; GNU Emacs is free software: you can redistribute it and/or modify ;; it under the terms of the GNU General Public License as published by -;; the Free Software Foundation; either version 3, or (at your option) -;; any later version. +;; the Free Software Foundation, either version 3 of the License, or +;; (at your option) any later version. ;; GNU Emacs is distributed in the hope that it will be useful, ;; but WITHOUT ANY WARRANTY; without even the implied warranty of @@ -19,15 +20,12 @@ ;; GNU General Public License for more details. ;; You should have received a copy of the GNU General Public License -;; along with GNU Emacs; see the file COPYING. If not, write to the -;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, -;; Boston, MA 02110-1301, USA. +;; along with GNU Emacs. If not, see . ;;; Commentary: ;;; Code: -;;;###autoload (defconst reference-point-alist '((tl . 0) (tc . 1) (tr . 2) (Bl . 3) (Bc . 4) (Br . 5) @@ -42,8 +40,7 @@ (mid-left . 3) (mid-center . 10) (mid-right . 5)) "Alist of symbols vs integer codes of glyph reference points. A glyph reference point symbol is to be used to specify a composition -rule in COMPONENTS argument to such functions as `compose-region' and -`make-composition'. +rule in COMPONENTS argument to such functions as `compose-region'. Meanings of glyph reference point codes are as follows: @@ -76,7 +73,12 @@ follows (the point `*' corresponds to both reference points): | | new | | |glyph| +----+-----+ <--- new descent -") + +A composition rule may have the form \(GLOBAL-REF-POINT +NEW-REF-POINT XOFF YOFF), where XOFF and YOFF specifies how much +to shift NEW-REF-POINT from GLOBAL-REF-POINT. In this case, XOFF +and YOFF are integers in the range -100..100 representing the +shifting percentage against the font size.") ;;;###autoload @@ -91,17 +93,29 @@ RULE is a cons of global and new reference point symbols (if (and (integerp rule) (< rule 144)) ;; Already encoded. rule - (or (consp rule) - (error "Invalid composition rule: %S" rule)) - (let ((gref (car rule)) - (nref (cdr rule))) - (or (integerp gref) - (setq gref (cdr (assq gref reference-point-alist)))) - (or (integerp nref) - (setq nref (cdr (assq nref reference-point-alist)))) - (or (and (>= gref 0) (< gref 12) (>= nref 0) (< nref 12)) - (error "Invalid composition rule: %S" rule)) - (+ (* gref 12) nref)))) + (if (consp rule) + (let ((gref (car rule)) + (nref (cdr rule)) + xoff yoff) + (if (consp nref) ; (GREF NREF XOFF YOFF) + (progn + (setq xoff (nth 1 nref) + yoff (nth 2 nref) + nref (car nref)) + (or (and (>= xoff -100) (<= xoff 100) + (>= yoff -100) (<= yoff 100)) + (error "Invalid composition rule: %s" rule)) + (setq xoff (+ xoff 128) yoff (+ yoff 128))) + ;; (GREF . NREF) + (setq xoff 0 yoff 0)) + (or (integerp gref) + (setq gref (cdr (assq gref reference-point-alist)))) + (or (integerp nref) + (setq nref (cdr (assq nref reference-point-alist)))) + (or (and (>= gref 0) (< gref 12) (>= nref 0) (< nref 12)) + (error "Invalid composition rule: %S" rule)) + (logior (lsh xoff 16) (lsh yoff 8) (+ (* gref 12) nref))) + (error "Invalid composition rule: %S" rule)))) ;; Decode encoded composition rule RULE-CODE. The value is a cons of ;; global and new reference point symbols. @@ -109,13 +123,20 @@ RULE is a cons of global and new reference point symbols ;; defined in composite.h. (defun decode-composition-rule (rule-code) - (or (and (natnump rule-code) (< rule-code 144)) + (or (and (natnump rule-code) (< rule-code #x1000000)) (error "Invalid encoded composition rule: %S" rule-code)) - (let ((gref (car (rassq (/ rule-code 12) reference-point-alist))) - (nref (car (rassq (% rule-code 12) reference-point-alist)))) + (let ((xoff (lsh rule-code -16)) + (yoff (logand (lsh rule-code -8) #xFF)) + gref nref) + (setq rule-code (logand rule-code #xFF) + gref (car (rassq (/ rule-code 12) reference-point-alist)) + nref (car (rassq (% rule-code 12) reference-point-alist))) (or (and gref (symbolp gref) nref (symbolp nref)) (error "Invalid composition rule code: %S" rule-code)) - (cons gref nref))) + (if (and (= xoff 0) (= yoff 0)) + (cons gref nref) + (setq xoff (- xoff 128) yoff (- yoff 128)) + (list gref xoff yoff nref)))) ;; Encode composition rules in composition components COMPONENTS. The ;; value is a copy of COMPONENTS, where composition rules (cons of @@ -159,7 +180,6 @@ RULE is a cons of global and new reference point symbols (setq i (+ i 2)))) components) -;;;###autoload (defun compose-region (start end &optional components modification-func) "Compose characters in the current region. @@ -171,14 +191,18 @@ When called from a program, expects these four arguments. First two arguments START and END are positions (integers or markers) specifying the region. -Optional 3rd argument COMPONENTS, if non-nil, is a character or a -sequence (vector, list, or string) of integers. In this case, -characters are composed not relatively but according to COMPONENTS. +Optional 3rd argument COMPONENTS, if non-nil, is a character, a string +or a vector or list of integers and rules. If it is a character, it is an alternate character to display instead of the text in the region. -If it is a string, the elements are alternate characters. +If it is a string, the elements are alternate characters. In +this case, TAB element has a special meaning. If the first +characer is TAB, the glyphs are displayed with left padding space +so that no pixel overlaps with the previous column. If the last +character is TAB, the glyphs are displayed with rigth padding +space so that no pixel overlaps with the following column. If it is a vector or list, it is a sequence of alternate characters and composition rules, where (2N)th elements are characters and (2N+1)th @@ -200,7 +224,6 @@ text in the composition." (compose-region-internal start end components modification-func) (restore-buffer-modified-p modified-p))) -;;;###autoload (defun decompose-region (start end) "Decompose text in the current region. @@ -212,11 +235,10 @@ positions (integers or markers) specifying the region." (remove-text-properties start end '(composition nil)) (restore-buffer-modified-p modified-p))) -;;;###autoload (defun compose-string (string &optional start end components modification-func) "Compose characters in string STRING. -The return value is STRING where `composition' property is put on all +The return value is STRING with the `composition' property put on all the characters in it. Optional 2nd and 3rd arguments START and END specify the range of @@ -237,13 +259,11 @@ text in the composition." (compose-string-internal string start end components modification-func) string) -;;;###autoload (defun decompose-string (string) "Return STRING where `composition' property is removed." (remove-text-properties 0 (length string) '(composition nil) string) string) -;;;###autoload (defun compose-chars (&rest args) "Return a string from arguments in which all characters are composed. For relative composition, arguments are characters. @@ -267,7 +287,6 @@ A composition rule is a cons of glyph reference points of the form (setq str (concat args))) (compose-string-internal str 0 (length str) components))) -;;;###autoload (defun find-composition (pos &optional limit string detail-p) "Return information about a composition at or nearest to buffer position POS. @@ -275,7 +294,7 @@ If the character at POS has `composition' property, the value is a list of FROM, TO, and VALID-P. FROM and TO specify the range of text that has the same `composition' -property, VALID-P is non-nil if and only if this composition is valid. +property, VALID-P is t if this composition is valid, and nil if not. If there's no composition at POS, and the optional 2nd argument LIMIT is non-nil, search for a composition toward LIMIT. @@ -299,56 +318,61 @@ and composition rules as described in `compose-region'. MOD-FUNC is a modification function of the composition. -WIDTH is a number of columns the composition occupies on the screen." +WIDTH is a number of columns the composition occupies on the screen. + +When Automatic Compostion mode is on, this function also finds a +chunk of text that is automatically composed. If such a chunk is +found closer to POS than the position that has `composition' +property, the value is a list of FROM, TO, and a glyph gstring +the specify how the chunk is composed. See the function +`composition-get-gstring' for the format of the glyph string." (let ((result (find-composition-internal pos limit string detail-p))) - (if (and detail-p result (nth 2 result) (not (nth 3 result))) + (if (and detail-p (> (length result) 3) (nth 2 result) (not (nth 3 result))) ;; This is a valid rule-base composition. (decode-composition-components (nth 2 result) 'nocopy)) result)) -;;;###autoload (defun compose-chars-after (pos &optional limit object) "Compose characters in current buffer after position POS. -It looks up the char-table `composition-function-table' (which see) by -a character after POS. If non-nil value is found, the format of the -value should be an alist of PATTERNs vs FUNCs, where PATTERNs are -regular expressions and FUNCs are functions. If the text after POS -matches one of PATTERNs, call the corresponding FUNC with three -arguments POS, TO, and PATTERN, where TO is the end position of text -matching PATTERN, and return what FUNC returns. Otherwise, return -nil. - -FUNC is responsible for composing the text properly. The return value -is: - nil -- if no characters were composed. - CHARS (integer) -- if CHARS characters were composed. +It looks up the char-table `composition-function-table' (which +see) by a character at POS, and compose characters after POS +according to the contents of `composition-function-table'. -Optional 2nd arg LIMIT, if non-nil, limits the matching of text. +Optional 2nd arg LIMIT, if non-nil, limits characters to compose. Optional 3rd arg OBJECT, if non-nil, is a string that contains the -text to compose. In that case, POS and LIMIT index to the string. +text to compose. In that case, POS and LIMIT index into the string. This function is the default value of `compose-chars-after-function'." (let ((tail (aref composition-function-table (char-after pos))) + (font-obj (and (display-multi-font-p) + (and (not (stringp object)) + (font-at pos (selected-window))))) pattern func result) - (when tail + (or limit + (setq limit (if (stringp object) (length object) (point-max)))) + (when (and font-obj tail) (save-match-data (save-excursion - (while (and tail (not func)) - (setq pattern (car (car tail)) - func (cdr (car tail))) + (while tail + (if (functionp (car tail)) + (setq pattern nil func (car tail)) + (setq pattern (car (car tail)) + func (cdr (car tail)))) (goto-char pos) - (if (if limit - (and (re-search-forward pattern limit t) - (= (match-beginning 0) pos)) - (looking-at pattern)) - (setq result (funcall func pos (match-end 0) pattern nil)) - (setq func nil tail (cdr tail))))))) - result)) + (if pattern + (if (and (if (stringp object) + (eq (string-match pattern object) 0) + (looking-at pattern)) + (<= (match-end 0) limit)) + (setq result + (funcall func pos (match-end 0) font-obj object))) + (setq result (funcall func pos limit font-obj object))) + (if result (setq tail nil)))))) + result)) -;;;###autoload (defun compose-last-chars (args) "Compose last characters. The argument is a parameterized event of the form @@ -369,13 +393,459 @@ after a sequence of character events." (compose-region (- (point) chars) (point) (nth 2 args)) (compose-chars-after (- (point) chars) (point)))))) -;;;###autoload(global-set-key [compose-last-chars] 'compose-last-chars) +(global-set-key [compose-last-chars] 'compose-last-chars) + + +;;; Automatic character composition. + +;; Copied from font-lock.el. +(eval-when-compile + ;; Borrowed from lazy-lock.el. + ;; We use this to preserve or protect things when modifying text properties. + (defmacro save-buffer-state (varlist &rest body) + "Bind variables according to VARLIST and eval BODY restoring buffer state." + `(let* ,(append varlist + '((modified (buffer-modified-p)) (buffer-undo-list t) + (inhibit-read-only t) (inhibit-point-motion-hooks t) + (inhibit-modification-hooks t) + deactivate-mark buffer-file-name buffer-file-truename)) + ,@body + (unless modified + (restore-buffer-modified-p nil)))) + ;; Fixme: This makes bootstrapping fail with this error. + ;; Symbol's function definition is void: eval-defun + ;;(def-edebug-spec save-buffer-state let) + ) + +(put 'save-buffer-state 'lisp-indent-function 1) + +;; These macros must match with C macros LGSTRING_XXX and LGLYPH_XXX in font.h +(defsubst lgstring-header (gstring) (aref gstring 0)) +(defsubst lgstring-set-header (gstring header) (aset gstring 0 header)) +(defsubst lgstring-font (gstring) (aref (lgstring-header gstring) 0)) +(defsubst lgstring-char (gstring i) (aref (lgstring-header gstring) (1+ i))) +(defsubst lgstring-char-len (gstring) (1- (length (lgstring-header gstring)))) +(defsubst lgstring-shaped-p (gstring) (aref gstring 1)) +(defsubst lgstring-set-id (gstring id) (aset gstring 1 id)) +(defsubst lgstring-glyph (gstring i) (aref gstring (+ i 2))) +(defsubst lgstring-glyph-len (gstring) (- (length gstring) 2)) +(defsubst lgstring-set-glyph (gstring i glyph) (aset gstring (+ i 2) glyph)) + +(defsubst lglyph-from (glyph) (aref glyph 0)) +(defsubst lglyph-to (glyph) (aref glyph 1)) +(defsubst lglyph-char (glyph) (aref glyph 2)) +(defsubst lglyph-code (glyph) (aref glyph 3)) +(defsubst lglyph-width (glyph) (aref glyph 4)) +(defsubst lglyph-lbearing (glyph) (aref glyph 5)) +(defsubst lglyph-rbearing (glyph) (aref glyph 6)) +(defsubst lglyph-ascent (glyph) (aref glyph 7)) +(defsubst lglyph-descent (glyph) (aref glyph 8)) +(defsubst lglyph-adjustment (glyph) (aref glyph 9)) + +(defsubst lglyph-set-from-to (glyph from to) + (progn (aset glyph 0 from) (aset glyph 1 to))) +(defsubst lglyph-set-char (glyph char) (aset glyph 2 char)) +(defsubst lglyph-set-code (glyph code) (aset glyph 3 code)) +(defsubst lglyph-set-width (glyph width) (aset glyph 4 width)) +(defsubst lglyph-set-adjustment (glyph &optional xoff yoff wadjust) + (aset glyph 9 (vector (or xoff 0) (or yoff 0) (or wadjust 0)))) + +(defsubst lglyph-copy (glyph) (copy-sequence glyph)) + +(defun lgstring-insert-glyph (gstring idx glyph) + (let ((nglyphs (lgstring-glyph-len gstring)) + (i idx) g) + (while (and (< i nglyphs) (setq g (lgstring-glyph gstring i))) + (setq i (1+ i))) + (if (= i nglyphs) + (setq gstring (vconcat gstring (vector glyph))) + (if (< (1+ i) nglyphs) + (lgstring-set-glyph gstring (1+ i) nil))) + (while (> i idx) + (lgstring-set-glyph gstring i (lgstring-glyph gstring (1- i))) + (setq i (1- i))) + (lgstring-set-glyph gstring i glyph) + gstring)) + +(defun compose-glyph-string (gstring from to) + (let ((glyph (lgstring-glyph gstring from)) + from-pos to-pos + ascent descent lbearing rbearing) + (setq from-pos (lglyph-from glyph) + to-pos (lglyph-to (lgstring-glyph gstring (1- to)))) + (lglyph-set-from-to glyph from-pos to-pos) + (setq from (1+ from)) + (while (and (< from to) + (setq glyph (lgstring-glyph gstring from))) + (lglyph-set-from-to glyph from-pos to-pos) + (let ((xoff (if (<= (lglyph-rbearing glyph) 0) 0 + (- (lglyph-width glyph))))) + (lglyph-set-adjustment glyph xoff 0 0)) + (setq from (1+ from))) + gstring)) + +(defun compose-glyph-string-relative (gstring from to &optional gap) + (let ((font-object (lgstring-font gstring)) + (glyph (lgstring-glyph gstring from)) + from-pos to-pos + ascent descent lbearing rbearing) + (if gap + (setq gap (floor (* (font-get font-object :size) gap))) + (setq gap 0)) + (setq from-pos (lglyph-from glyph) + to-pos (lglyph-to (lgstring-glyph gstring (1- to))) + ascent (lglyph-ascent glyph) + descent (lglyph-descent glyph)) + (lglyph-set-from-to glyph from-pos to-pos) + (setq from (1+ from)) + (while (< from to) + (setq glyph (lgstring-glyph gstring from)) + (lglyph-set-from-to glyph from-pos to-pos) + (let ((this-ascent (lglyph-ascent glyph)) + (this-descent (lglyph-descent glyph)) + xoff yoff wadjust) + (setq xoff (if (<= (lglyph-rbearing glyph) 0) 0 + (- (lglyph-width glyph)))) + (if (> this-ascent 0) + (if (< this-descent 0) + (setq yoff (- 0 ascent gap this-descent) + ascent (+ ascent gap this-ascent this-descent)) + (setq yoff 0)) + (setq yoff (+ descent gap this-ascent) + descent (+ descent gap this-ascent this-descent))) + (if (or (/= xoff 0) (/= yoff 0)) + (lglyph-set-adjustment glyph xoff yoff 0))) + (setq from (1+ from))) + gstring)) + +(defun compose-gstring-for-graphic (gstring) + "Compose glyph-string GSTRING for graphic display. +Non-spacing characters are composed with the preceding base +character. If the preceding character is not a base character, +each non-spacing character is composed as a spacing character by +a padding space before and/or after the character. + +All non-spacing characters has this function in +`composition-function-table' unless overwritten." + (let* ((header (lgstring-header gstring)) + (nchars (lgstring-char-len gstring)) + (nglyphs (lgstring-glyph-len gstring)) + (glyph (lgstring-glyph gstring 0))) + (cond + ;; A non-spacing character not following a proper base character. + ((= nchars 1) + (let ((lbearing (lglyph-lbearing glyph)) + (rbearing (lglyph-rbearing glyph)) + (width (lglyph-width glyph)) + xoff wadjust) + (if (< lbearing 0) + (setq xoff (- lbearing)) + (setq xoff 0 lbearing 0)) + (if (< rbearing width) + (setq rbearing width)) + (lglyph-set-adjustment glyph xoff 0 (- rbearing lbearing)) + gstring)) + + ;; This sequence doesn't start with a proper base character. + ((memq (get-char-code-property (lgstring-char gstring 0) + 'general-category) + '(Mn Mc Me Zs Zl Zp Cc Cf Cs)) + nil) + + ;; A base character and the following non-spacing characters. + (t + (let ((gstr (font-shape-gstring gstring))) + (if (and gstr + (> (lglyph-to (lgstring-glyph gstr 0)) 0)) + gstr + ;; The shaper of the font couldn't shape the gstring. + ;; Shape them according to canonical-combining-class. + (lgstring-set-id gstring nil) + (let* ((width (lglyph-width glyph)) + (ascent (lglyph-ascent glyph)) + (descent (lglyph-descent glyph)) + (rbearing (lglyph-rbearing glyph)) + (lbearing (lglyph-lbearing glyph)) + (center (/ (+ lbearing rbearing) 2)) + (gap (round (* (font-get (lgstring-font gstring) :size) 0.1))) + xoff yoff) + (dotimes (i nchars) + (setq glyph (lgstring-glyph gstring i)) + (when (> i 0) + (let* ((class (get-char-code-property + (lglyph-char glyph) 'canonical-combining-class)) + (lb (lglyph-lbearing glyph)) + (rb (lglyph-rbearing glyph)) + (as (lglyph-ascent glyph)) + (de (lglyph-descent glyph)) + (ce (/ (+ lb rb) 2)) + xoff yoff) + (when (and class (>= class 200) (<= class 240)) + (setq xoff 0 yoff 0) + (cond + ((= class 200) + (setq xoff (- lbearing ce) + yoff (if (> as 0) 0 (+ descent as)))) + ((= class 202) + (if (> as 0) (setq as 0)) + (setq xoff (- center ce) + yoff (if (> as 0) 0 (+ descent as)))) + ((= class 204) + (if (> as 0) (setq as 0)) + (setq xoff (- rbearing ce) + yoff (if (> as 0) 0 (+ descent as)))) + ((= class 208) + (setq xoff (- lbearing rb))) + ((= class 210) + (setq xoff (- rbearing lb))) + ((= class 212) + (setq xoff (- lbearing ce) + yoff (if (>= de 0) 0 (- (- ascent) de)))) + ((= class 214) + (setq xoff (- center ce) + yoff (if (>= de 0) 0 (- (- ascent) de)))) + ((= class 216) + (setq xoff (- rbearing ce) + yoff (if (>= de 0) 0 (- (- ascent) de)))) + ((= class 218) + (setq xoff (- lbearing ce) + yoff (if (> as 0) 0 (+ descent as gap)))) + ((= class 220) + (setq xoff (- center ce) + yoff (if (> as 0) 0 (+ descent as gap)))) + ((= class 222) + (setq xoff (- rbearing ce) + yoff (if (> as 0) 0 (+ descent as gap)))) + ((= class 224) + (setq xoff (- lbearing rb))) + ((= class 226) + (setq xoff (- rbearing lb))) + ((= class 228) + (setq xoff (- lbearing ce) + yoff (if (>= de 0) 0 (- (- ascent) de gap)))) + ((= class 230) + (setq xoff (- center ce) + yoff (if (>= de 0) 0 (- (- ascent) de gap)))) + ((= class 232) + (setq xoff (- rbearing ce) + yoff (if (>= de 0) 0 (- (+ ascent de) gap))))) + (lglyph-set-adjustment glyph (- xoff width) yoff) + (setq lb (+ lb xoff) + rb (+ lb xoff) + as (- as yoff) + de (+ de yoff))) + (if (< ascent as) + (setq ascent as)) + (if (< descent de) + (setq descent de)))))) + (let ((i 0)) + (while (and (< i nglyphs) (setq glyph (lgstring-glyph gstring i))) + (lglyph-set-from-to glyph 0 (1- nchars)) + (setq i (1+ i)))) + gstring)))))) + +(let ((elt '(["[[:alpha:]]\\c^+" 1 compose-gstring-for-graphic] + [nil 0 compose-gstring-for-graphic]))) + (map-char-table + #'(lambda (key val) + (if (= val 0) + (set-char-table-range composition-function-table key elt))) + char-width-table)) + +(defun compose-gstring-for-terminal (gstring) + "Compose glyph string GSTRING for terminal display. +Non-spacing characters are composed with the preceding base +character. If the preceding character is not a base character, +each non-spacing character is composed as a spacing character by +a prepending a space before it." + (let* ((header (lgstring-header gstring)) + (nchars (lgstring-char-len gstring)) + (nglyphs (lgstring-glyph-len gstring)) + (i 0) + glyph) + (while (and (< i nglyphs) + (setq glyph (lgstring-glyph gstring i))) + (if (= (lglyph-width glyph) 0) + (progn + ;; Compose by prepending a space. + (setq gstring (lgstring-insert-glyph gstring i (lglyph-copy glyph)) + nglyphs (lgstring-glyph-len gstring)) + (lglyph-set-char (lgstring-glyph gstring i) 32) + (setq i (+ 2))) + (let ((from (lglyph-from glyph)) + (to (lglyph-to glyph)) + (j (1+ i))) + (while (and (< j nglyphs) + (setq glyph (lgstring-glyph gstring j)) + (= (lglyph-width glyph) 0)) + (setq to (lglyph-to glyph) + j (1+ j))) + (while (< i j) + (setq glyph (lgstring-glyph gstring i)) + (lglyph-set-from-to glyph from to) + (setq i (1+ i)))))) + gstring)) + + +(defun auto-compose-chars (func from to font-object string) + "Compose the characters at FROM by FUNC. +FUNC is called with one argument GSTRING which is built for characters +in the region FROM (inclusive) and TO (exclusive). + +If the character are composed on a graphic display, FONT-OBJECT +is a font to use. + +Otherwise, FONT-OBJECT is nil, and the fucntion +`compose-gstring-for-terminal' is used instead of FUNC. + +If STRING is non-nil, it is a string, and FROM and TO are indices +into the string. In that case, compose characters in the string. + +The value is a gstring containing information for shaping the characters. + +This function is the default value of `auto-composition-function' (which see)." + (let ((gstring (composition-get-gstring from to font-object string))) + (if (lgstring-shaped-p gstring) + gstring + (or font-object + (setq func 'compose-gstring-for-terminal)) + (funcall func gstring)))) + +(make-variable-buffer-local 'auto-composition-function) + +;;;###autoload +(define-minor-mode auto-composition-mode + "Toggle Auto Composition mode. +With ARG, turn Auto Composition mode off if and only if ARG is a non-positive +number; if ARG is nil, toggle Auto Composition mode; anything else turns Auto +Composition on. + +When Auto Composition is enabled, text characters are automatically composed +by functions registered in `composition-function-table' (which see). + +You can use `global-auto-composition-mode' to turn on +Auto Composition mode in all buffers (this is the default)." + nil nil nil + (if noninteractive + (setq auto-composition-mode nil)) + (cond (auto-composition-mode + (add-hook 'after-change-functions 'auto-composition-after-change nil t) + (setq auto-composition-function 'auto-compose-chars)) + (t + (remove-hook 'after-change-functions 'auto-composition-after-change t) + (setq auto-composition-function nil))) + (save-buffer-state nil + (save-restriction + (widen) + (remove-text-properties (point-min) (point-max) '(auto-composed nil)) + (decompose-region (point-min) (point-max))))) + +(defun auto-composition-after-change (start end old-len) + (save-buffer-state nil + (if (< start (point-min)) + (setq start (point-min))) + (if (> end (point-max)) + (setq end (point-max))) + (when (and auto-composition-mode (not memory-full)) + (let (func1 func2) + (when (and (> start (point-min)) + (setq func2 (aref composition-function-table + (char-after (1- start)))) + (or (= start (point-max)) + (not (setq func1 (aref composition-function-table + (char-after start)))) + (eq func1 func2))) + (setq start (1- start) + func1 func2) + (while (eq func1 func2) + (if (> start (point-min)) + (setq start (1- start) + func2 (aref composition-function-table + (char-after start))) + (setq func2 nil)))) + (when (and (< end (point-max)) + (setq func2 (aref composition-function-table + (char-after end))) + (or (= end (point-min)) + (not (setq func1 (aref composition-function-table + (char-after (1- end))))) + (eq func1 func2))) + (setq end (1+ end) + func1 func2) + (while (eq func1 func2) + (if (< end (point-max)) + (setq func2 (aref composition-function-table + (char-after end)) + end (1+ end)) + (setq func2 nil)))) + (if (< start end) + (remove-text-properties start end '(auto-composed nil))))))) + +(defun turn-on-auto-composition-if-enabled () + (if enable-multibyte-characters + (auto-composition-mode 1))) + +;;;###autoload +(define-global-minor-mode global-auto-composition-mode + auto-composition-mode turn-on-auto-composition-if-enabled + :extra-args (dummy) + :initialize 'custom-initialize-safe-default + :init-value (not noninteractive) + :group 'auto-composition + :version "23.1") + +(defun toggle-auto-composition (&optional arg) + "Change whether automatic character composition is enabled in this buffer. +With arg, enable it if and only if arg is positive." + (interactive "P") + (let ((enable (if (null arg) (not auto-composition-function) + (> (prefix-numeric-value arg) 0)))) + (if enable + (kill-local-variable 'auto-composition-function) + (make-local-variable 'auto-composition-function) + (setq auto-composition-function nil) + (save-buffer-state nil + (save-restriction + (widen) + (decompose-region (point-min) (point-max))))) + + (save-buffer-state nil + (save-restriction + (widen) + (remove-text-properties (point-min) (point-max) + '(auto-composed nil)))))) + +(defun auto-compose-region (from to) + "Force automatic character composition on the region FROM and TO." + (save-excursion + (if (get-text-property from 'auto-composed) + (setq from (next-single-property-change from 'auto-composed nil to))) + (goto-char from) + (let ((modified-p (buffer-modified-p)) + (inhibit-read-only '(composition auto-composed)) + (stop (next-single-property-change (point) 'auto-composed nil to))) + (while (< (point) to) + (if (= (point) stop) + (progn + (goto-char (next-single-property-change (point) + 'auto-composed nil to)) + (setq stop (next-single-property-change (point) + 'auto-composed nil to))) + (let ((func (aref composition-function-table (following-char))) + (font-obj (and (display-multi-font-p) + (font-at (point) (selected-window)))) + (pos (point))) + (if (and (functionp func) font-obj) + (goto-char (funcall func (point) to font-obj nil))) + (if (<= (point) pos) + (forward-char 1))))) + (put-text-property from to 'auto-composed t) + (set-buffer-modified-p modified-p)))) ;; The following codes are only for backward compatibility with Emacs ;; 20.4 and earlier. -;;;###autoload (defun decompose-composite-char (char &optional type with-composition-rule) "Convert CHAR to string. @@ -387,7 +857,6 @@ Optional 3rd arg WITH-COMPOSITION-RULE is ignored." ((eq type 'list) (list char)) (t (vector char)))) -;;;###autoload (make-obsolete 'decompose-composite-char 'char-to-string "21.1")