More tweaks of skeleton documentation wrt \n behavior at bol/eol.

[bpt/emacs.git] / lisp / composite.el

diff --git a/lisp/composite.el b/lisp/composite.el
index 3c25b8b..b46d41a 100644 (file)
--- a/lisp/composite.el
+++ b/lisp/composite.el
@@ -1,5 +1,7 @@
 ;;; composite.el --- support character composition
 
+;; Copyright (C) 2001-2014 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)
@@ -555,7 +557,11 @@ All non-spacing characters have this function in
                 (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)
@@ -566,8 +572,10 @@ All non-spacing characters have this function in
                       (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)
@@ -621,6 +629,38 @@ All non-spacing characters have this function in
                          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)
@@ -631,13 +671,15 @@ All non-spacing characters have this function in
              (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))
+;; 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)))
 
 (defun compose-gstring-for-terminal (gstring)
   "Compose glyph-string GSTRING for terminal display.