Updates for Display chapter of Lisp manual.

* doc/lispref/display.texi (Image Formats): Add imagemagick type.
(Image Descriptors): Mention how they are used.
(ImageMagick Images): Clarify role of imagemagick-register-types.
(Character Display): Don't mention glyph tables.
(Display Tables): Use make-glyph-code in example.
(Glyphs): Avoid "simple glyph code" terminology.  Note that glyph
tables are semi-obsolete.  De-document create-glyph.
(Glyphless Chars): Note that display tables override this.
(Bidirectional Display): Copyedits.  Introduce "bidirectional
reordering" terminology, and use it.

* doc/emacs/files.texi (File Conveniences): Clarify Imagemagick discussion.

* lisp/image.el (imagemagick-types-inhibit)
(imagemagick-register-types): Doc fix.

1 files changed, 14 insertions, 12 deletions

diff --git a/lisp/image.el b/lisp/image.el
index 162cc8bb0ed..be1b1ef8f48 100644
--- a/lisp/image.el
+++ b/lisp/image.el
@@ -686,14 +686,13 @@ The minimum delay between successive frames is 0.01s."
 
 (defcustom imagemagick-types-inhibit
   '(C HTML HTM TXT PDF)
-  "ImageMagick types that Emacs should not use ImageMagick to handle.
-This should be a list of symbols, each of which has the same
-name as one of the format tags used internally by ImageMagick;
-see `imagemagick-types'.  Entries in this list are excluded from
-being registered by `imagemagick-register-types', so if you change
-this variable you must do so before you call that function.
-
-If Emacs is compiled without ImageMagick, this variable has no effect."
+  "ImageMagick types that should not be visited in Image mode.
+This should be a list of symbols, each of which should be one of
+the ImageMagick types listed in `imagemagick-types'.  These image
+types are not registered by `imagemagick-register-types'.
+
+If Emacs is compiled without ImageMagick support, this variable
+has no effect."
   :type '(choice (const :tag "Let ImageMagick handle all types it can" nil)
 		 (repeat symbol))
   ;; Ideally, would have a :set function that checks if we already did
@@ -704,10 +703,13 @@ If Emacs is compiled without ImageMagick, this variable has no effect."
 ;;;###autoload
 (defun imagemagick-register-types ()
   "Register file types that can be handled by ImageMagick.
-This adds the file types returned by `imagemagick-types'
-\(excluding the ones in `imagemagick-types-inhibit') to
-`auto-mode-alist' and `image-type-file-name-regexps', so that
-Emacs visits them in Image mode.
+This registers the ImageMagick types listed in `imagemagick-types',
+excluding those listed in `imagemagick-types-inhibit'.
+
+Registered image types are added to `auto-mode-alist', so that
+Emacs visits them in Image mode.  They are also added to
+`image-type-file-name-regexps', so that the `image-type' function
+recognizes these files as having image type `imagemagick'.
 
 If Emacs is compiled without ImageMagick support, do nothing."
   (when (fboundp 'imagemagick-types)