Implement inline display of linked images

doc/ChangeLog

@@ -1,3 +1,9 @@
+2010-05-08  Carsten Dominik  <carsten.dominik@gmail.com>
+
+	* orgcard.tex: Document inline image toggling.
+
+	* org.texi (Handling links): Document inline image toggling.
+
 2010-05-07  Carsten Dominik  <carsten.dominik@gmail.com>
 
 	* org.texi (Updating the table): Document new buffer-wide

doc/org.texi

@@ -2983,14 +2983,14 @@ to the current directory using @samp{../}.  Otherwise an absolute path
 is used, if possible with @samp{~/} for your home directory.  You can
 force an absolute path with two @kbd{C-u} prefixes.
 @c
-@item C-c C-l @r{(with cursor on existing link)}
+@item C-c C-l @ @r{(with cursor on existing link)}
 When the cursor is on an existing link, @kbd{C-c C-l} allows you to edit the
 link and description parts of the link.
 @c
 @cindex following links
 @kindex C-c C-o
-@kindex RET
-@item C-c C-o @r{or} @key{RET}
+@kindex @key{RET}
+@item C-c C-o @ @r{(or, if @code{org-return-follows-link} is set, also} @key{RET}
 @vindex org-file-apps
 Open link at point.  This will launch a web browser for URLs (using
 @command{browse-url-at-point}), run VM/MH-E/Wanderlust/Rmail/Gnus/BBDB for
@@ -3021,6 +3021,14 @@ Like @kbd{mouse-2}, but force file links to be opened with Emacs, and
 internal links to be displayed in another window@footnote{See the
 variable @code{org-display-internal-link-with-indirect-buffer}}.
 @c
+@cindex inlining images
+@cindex images, inlining
+@kindex C-c C-x C-v
+@item C-c C-x C-v
+Toggle the inline display of linked images.  Normally this will only inline
+images that have no description part in the link, i.e. images that will also
+be inlined during export.  When called with a prefix argument, also display
+images that do have a link description.
 @cindex mark ring
 @kindex C-c %
 @item C-c %

doc/orgcard.tex

@@ -442,6 +442,7 @@ formula, \kbd{:=} a field formula.
 \key{find next link}{C-c C-x C-n}
 \key{find previous link}{C-c C-x C-p}
 \key{edit code snippet of file at point}{C-c '}
+\key{toggle inline display of linked images}{C-c C-x C-v}
 
 {\bf Internal Links}
 

lisp/ChangeLog

@@ -1,3 +1,10 @@
+2010-05-08  Carsten Dominik  <carsten.dominik@gmail.com>
+
+	* org.el (org-inline-image-overlays): New variable.
+	(org-toggle-inline-images, org-display-inline-images)
+	(org-remove-inline-images): New commands.
+	(org-mode-map): Define a key for `org-toggle-inline-images'.
+
 2010-05-08  David Maus  <dmaus@ictsoc.de>
 
 	* org-wl.el (org-wl-message-field): New function.  Return

lisp/org.el

@@ -1295,8 +1295,7 @@ implementation is bad."
   :type 'boolean)
 
 (defcustom org-return-follows-link nil
-  "Non-nil means on links RET will follow the link.
-Needs to be set before org.el is loaded."
+  "Non-nil means on links RET will follow the link."
   :group 'org-link-follow
   :type 'boolean)
 
@@ -15463,6 +15462,52 @@ SNIPPETS-P indicates if this is run to create snippet images for HTML."
   "Return string to be used as color value for an RGB component."
   (format "%g" (/ value 65535.0)))
 
+;; Image display
+
+
+(defvar org-inline-image-overlays nil)
+(make-variable-buffer-local 'org-inline-image-overlays)
+
+(defun org-toggle-inline-images (&optional include-linked)
+  "Toggle the display of inline images.
+INCLUDE-LINKED is passed to `org-display-inline-images'."
+  (interactive "P")
+  (if org-inline-image-overlays
+      (progn
+	(org-remove-inline-images)
+	(message "Inline image display turned off"))
+    (org-display-inline-images arg)
+    (if org-inline-image-overlays
+	(message "%d images displayed inline"
+		 (length org-inline-image-overlays))
+      (message "No images to display inline"))))
+
+(defun org-display-inline-images (&optional include-linked)
+  "Display inline images.
+Normally only links without a description part are inlined, because this
+is how it will work for export.  When INCLUDE-LINKED is set, also links
+with a description part will be inlined."
+  (interactive "P")
+  (org-remove-inline-images)
+  (goto-char (point-min))
+  (let ((re (concat "\\[\\[\\(file:\\|\\./\\)\\(~?" "[-+./_0-9a-zA-Z]+"
+		    (substring (org-image-file-name-regexp) 0 -2)
+		    "\\)\\]" (if include-linked "" "\\]")))
+	file ov)
+  (while (re-search-forward re nil t)
+    (setq file (expand-file-name (match-string 2)))
+    (when (file-exists-p file)
+      (setq ov (make-overlay (match-beginning 0) (match-end 0)))
+      (overlay-put ov 'display (create-image file))
+      (overlay-put ov 'face 'default)
+      (push ov org-inline-image-overlays)))))
+
+(defun org-remove-inline-images ()
+  "Remove inline display of images."
+  (interactive)
+  (mapc 'delete-overlay org-inline-image-overlays)
+  (setq org-inline-image-overlays nil))
+
 ;;;; Key bindings
 
 ;; Make `C-c C-x' a prefix key
@@ -15632,6 +15677,7 @@ SNIPPETS-P indicates if this is run to create snippet images for HTML."
 (org-defkey org-mode-map "\C-c\C-x\C-r" 'org-clock-report)
 (org-defkey org-mode-map "\C-c\C-x\C-u" 'org-dblock-update)
 (org-defkey org-mode-map "\C-c\C-x\C-l" 'org-preview-latex-fragment)
+(org-defkey org-mode-map "\C-c\C-x\C-v" 'org-toggle-inline-images)
 (org-defkey org-mode-map "\C-c\C-x\C-b" 'org-toggle-checkbox)
 (org-defkey org-mode-map "\C-c\C-xp"    'org-set-property)
 (org-defkey org-mode-map "\C-c\C-xe"    'org-set-effort)
@@ -18636,7 +18682,6 @@ To get rid of the restriction, use \\[org-agenda-remove-restriction-lock]."
      (add-hook 'speedbar-visiting-tag-hook
 	       (lambda () (and (org-mode-p) (org-show-context 'org-goto))))))
 
-
 ;;; Fixes and Hacks for problems with other packages
 
 ;; Make flyspell not check words in links, to not mess up our keymap