;;; composite.el --- support character composition
+;; Copyright (C) 2001-2016 Free Software Foundation, Inc.
+
;; Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
;; 2008, 2009, 2010, 2011
;; National Institute of Advanced Industrial Science and Technology (AIST)
| | 7:bc or bottom-center
6----7----8 <---- descent 8:br or bottom-right
-Glyph reference point symbols are to be used to specify composition
-rule of the form \(GLOBAL-REF-POINT . NEW-REF-POINT), where
+Glyph reference point symbols are to be used to specify a composition
+rule of the form (GLOBAL-REF-POINT . NEW-REF-POINT), where
GLOBAL-REF-POINT is a reference point in the overall glyphs already
composed, and NEW-REF-POINT is a reference point in the new glyph to
be added.
| | |
| global| |
| glyph | |
- -- | | |-- <--- baseline \(doesn't change)
+ -- | | |-- <--- baseline (doesn't change)
+----+--*--+
| | new |
| |glyph|
+----+-----+ <--- new descent
-A composition rule may have the form \(GLOBAL-REF-POINT
+A composition rule may have the form (GLOBAL-REF-POINT
NEW-REF-POINT XOFF YOFF), where XOFF and YOFF specify 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
(defun compose-chars (&rest args)
"Return a string from arguments in which all characters are composed.
For relative composition, arguments are characters.
-For rule-based composition, Mth \(where M is odd) arguments are
-characters, and Nth \(where N is even) arguments are composition rules.
+For rule-based composition, Mth (where M is odd) arguments are
+characters, and Nth (where N is even) arguments are composition rules.
A composition rule is a cons of glyph reference points of the form
\(GLOBAL-REF-POINT . NEW-REF-POINT). See the documentation of
`reference-point-alist' for more detail."
(defun compose-last-chars (args)
"Compose last characters.
The argument is a parameterized event of the form
- \(compose-last-chars N COMPONENTS),
+ (compose-last-chars N COMPONENTS),
where N is the number of characters before point to compose,
COMPONENTS, if non-nil, is the same as the argument to `compose-region'
\(which see). If it is nil, `compose-chars-after' is called,
(rbearing (lglyph-rbearing glyph))
(lbearing (lglyph-lbearing glyph))
(center (/ (+ lbearing rbearing) 2))
+ ;; Artificial vertical gap between the glyphs.
(gap (round (* (font-get (lgstring-font gstring) :size) 0.1))))
+ (if (= gap 0)
+ ;; Assure at least 1 pixel vertical gap.
+ (setq gap 1))
(dotimes (i nchars)
(setq glyph (lgstring-glyph gstring i))
(when (> i 0)
(as (lglyph-ascent glyph))
(de (lglyph-descent glyph))
(ce (/ (+ lb rb) 2))
+ (w (lglyph-width glyph))
xoff yoff)
- (when (and class (>= class 200) (<= class 240))
+ (cond
+ ((and class (>= class 200) (<= class 240))
(setq xoff 0 yoff 0)
(cond
((= class 200)
rb (+ lb xoff)
as (- as yoff)
de (+ de yoff)))
+ ((and (= class 0)
+ (eq (get-char-code-property (lglyph-char glyph)
+ 'general-category) 'Me))
+ ;; Artificially laying out glyphs in an enclosing
+ ;; mark is difficult. All we can do is to adjust
+ ;; the x-offset and width of the base glyph to
+ ;; align it at the center of the glyph of the
+ ;; enclosing mark hoping that the enclosing mark
+ ;; is big enough. We also have to adjust the
+ ;; x-offset and width of the mark ifself properly
+ ;; depending on how the glyph is designed.
+
+ ;; (non-spacing or not). For instance, when we
+ ;; have these glyphs:
+ ;; X position |
+ ;; base: <-*-> lbearing=0 rbearing=5 width=5
+ ;; mark: <----------.> lb=-11 rb=2 w=0
+ ;; we get a correct layout by moving them as this:
+ ;; base: <-*-> XOFF=4 WAD=9
+ ;; mark: <----------.> xoff=2 wad=4
+ ;; we have moved the base to the left by 4-pixel
+ ;; and make its width 9-pixel, then move the mark
+ ;; to the left 2-pixel and make its width 4-pixel.
+ (let* (;; Adjustment for the base glyph
+ (XOFF (/ (- rb lb width) 2))
+ (WAD (+ width XOFF))
+ ;; Adjustment for the enclosing mark glyph
+ (xoff (- (+ lb WAD)))
+ (wad (- rb lb WAD)))
+ (lglyph-set-adjustment glyph xoff 0 wad)
+ (setq glyph (lgstring-glyph gstring 0))
+ (lglyph-set-adjustment glyph XOFF 0 WAD))))
(if (< ascent as)
(setq ascent as))
(if (< descent de)
(setq i (1+ i))))
gstring))))))
-(let ((elt `([,(purecopy "\\c.\\c^+") 1 compose-gstring-for-graphic]
- [nil 0 compose-gstring-for-graphic])))
- (map-char-table
- #'(lambda (key val)
- (if (memq val '(Mn Mc Me))
- (set-char-table-range composition-function-table key elt)))
- unicode-category-table))
+(defun compose-gstring-for-dotted-circle (gstring)
+ (let* ((dc (lgstring-glyph gstring 0)) ; glyph of dotted-circle
+ (dc-id (lglyph-code dc))
+ (fc (lgstring-glyph gstring 1)) ; glyph of the following char
+ (fc-id (lglyph-code fc))
+ (gstr (and nil (font-shape-gstring gstring))))
+ (if (and gstr
+ (or (= (lgstring-glyph-len gstr) 1)
+ (and (= (lgstring-glyph-len gstr) 2)
+ (= (lglyph-to (lgstring-glyph gstr 0))
+ (lglyph-to (lgstring-glyph gstr 1))))))
+ ;; It seems that font-shape-gstring has composed glyphs.
+ gstr
+ ;; Artificially compose the following glyph with the preceding
+ ;; dotted-circle.
+ (setq dc (lgstring-glyph gstring 0)
+ fc (lgstring-glyph gstring 1))
+ (let ((dc-width (lglyph-width dc))
+ (fc-width (- (lglyph-rbearing fc) (lglyph-lbearing fc)))
+ (from (lglyph-from dc))
+ (to (lglyph-to fc))
+ (xoff 0) (yoff 0) (width 0))
+ (if (and (< (lglyph-descent fc) 0)
+ (> (lglyph-ascent dc) (- (lglyph-descent fc))))
+ ;; Set YOFF so that the following glyph is put on top of
+ ;; the dotted-circle.
+ (setq yoff (- (- (lglyph-descent fc)) (lglyph-ascent dc))))
+ (if (> (lglyph-width fc) 0)
+ (setq xoff (- (lglyph-rbearing fc))))
+ (if (< dc-width fc-width)
+ ;; The following glyph is wider, but we don't know how to
+ ;; align both glyphs. So, try the easiest method;
+ ;; i.e. align left edges of the glyphs.
+ (setq xoff (- xoff (- dc-width) (- (lglyph-lbearing fc )))
+ width (- fc-width dc-width)))
+ (if (or (/= xoff 0) (/= yoff 0) (/= width 0) (/= (lglyph-width fc) 0))
+ (lglyph-set-adjustment fc xoff yoff width))
+ (lglyph-set-from-to dc from to)
+ (lglyph-set-from-to fc from to))
+ (if (> (lgstring-glyph-len gstring) 2)
+ (lgstring-set-glyph gstring 2 nil))
+ gstring)))
+
+;; Allow for bootstrapping without uni-*.el.
+(when unicode-category-table
+ (let ((elt `([,(purecopy "\\c.\\c^+") 1 compose-gstring-for-graphic]
+ [nil 0 compose-gstring-for-graphic])))
+ (map-char-table
+ #'(lambda (key val)
+ (if (memq val '(Mn Mc Me))
+ (set-char-table-range composition-function-table key elt)))
+ unicode-category-table))
+ ;; for dotted-circle
+ (aset composition-function-table #x25CC
+ `([,(purecopy ".\\c^") 0 compose-gstring-for-dotted-circle])))
(defun compose-gstring-for-terminal (gstring)
- "Compose glyph string GSTRING for terminal display.
+ "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
For more information on Auto Composition mode, see
`auto-composition-mode' ."
+ :global t
:variable (default-value 'auto-composition-mode))
(defalias 'toggle-auto-composition 'auto-composition-mode)