[LaTeX2PNG support
clinton@unknownlamer.org**20081001184313
 Setup latex2png with a few temporary hacks until the release of Muse 3.13
] hunk ./init.d/muse.el 95
+;;; Latex2png
+;;; This is a suboptimal solution for displaying math, but will have
+;;; to do until I figure out how to embed mathml with an img and raw
+;;; latex source backup...
+
+(require 'muse-latex2png)
+
+(setq muse-latex2png-img-dest "img/latex"
+      muse-latex2png-scale-factor 1.5)
+
+;;; this differs from Muse 3.12 in that it calls dvipng
+;;; with call-process so as to avoid issues with filenames with spaces
+;;; in them (patch has been sent upstream and merged for 3.13)
+(defun muse-latex2png (code prefix preamble)
+  "Convert the LaTeX CODE into a png file beginning with PREFIX.
+PREAMBLE indicates extra packages and definitions to include."
+  (unless preamble
+    (setq preamble ""))
+  (unless prefix
+    (setq prefix "muse-latex2png"))
+  (let* ((tmpdir (cond ((boundp 'temporary-file-directory)
+                        temporary-file-directory)
+                       ((fboundp 'temp-directory)
+                        (temp-directory))
+                       (t "/tmp")))
+         (texfile (expand-file-name
+                   (concat prefix "__"  (format "%d" (abs (sxhash code))))
+                   tmpdir))
+         (defalt-directory default-directory))
+    (with-temp-file (concat texfile ".tex")
+      (insert muse-latex2png-template)
+      (goto-char (point-min))
+      (while (search-forward "%preamble%" nil t)
+        (replace-match preamble nil t))
+      (goto-char (point-min))
+      (while (search-forward "%code%" nil t)
+        (replace-match code nil t)))
+    (setq default-directory tmpdir)
+    (call-process "latex" nil nil nil texfile)
+    (if (file-exists-p (concat texfile ".dvi"))
+        (progn
+          (call-process "dvipng" nil nil nil
+			"-E"
+			"-fg" muse-latex2png-fg
+			"-bg" muse-latex2png-bg
+			"-T" "tight"
+			"-x" (format  "%s" (* muse-latex2png-scale-factor 1000))
+			"-y" (format  "%s" (* muse-latex2png-scale-factor 1000))
+			"-o" (concat texfile ".png")
+			(concat texfile ".dvi"))
+          (if (file-exists-p (concat texfile ".png"))
+              (progn
+                (delete-file (concat texfile ".dvi"))
+                (delete-file (concat texfile ".tex"))
+                (delete-file (concat texfile ".aux"))
+                (delete-file (concat texfile ".log"))
+                (concat texfile ".png"))
+            (message "Failed to create png file")
+            nil))
+      (message (concat "Failed to create dvi file " texfile))
+      nil)))
+
+;;; This differs from Muse 3.12 in that it inserts <p></p> in html
+;;; derived styles for non-inline blocks
+;;; fixme: send patch
+(defun muse-latex2png-region (beg end attrs)
+  "Generate an image for the Latex code between BEG and END.
+If a Muse page is currently being published, replace the given
+region with the appropriate markup that displays the image.
+Otherwise, just return the path of the generated image.
+
+Valid keys for the ATTRS alist are as follows.
+
+prefix: The prefix given to the image file.
+preamble: Extra text to add to the Latex preamble.
+inline: Display image as inline, instead of a block."
+  (let ((end-marker (set-marker (make-marker) (1+ end)))
+        (pubdir (expand-file-name
+                 muse-latex2png-img-dest
+                 (file-name-directory muse-publishing-current-output-path))))
+    (save-restriction
+      (narrow-to-region beg end)
+      (let* ((text (buffer-substring-no-properties beg end))
+             ;; the prefix given to the image file.
+             (prefix (cdr (assoc "prefix" attrs)))
+             ;; preamble (for extra options)
+             (preamble (cdr (assoc "preamble" attrs)))
+             ;; display inline or as a block
+             (display (car (assoc "inline" attrs))))
+        (when muse-publishing-p
+          (delete-region beg end)
+          (goto-char (point-min)))
+        (unless (file-directory-p pubdir)
+          (make-directory pubdir))
+        (let ((path (muse-latex2png-move2pubdir
+                     (muse-latex2png text prefix preamble)
+                     prefix pubdir)))
+          (when path
+            (when muse-publishing-p
+              (muse-insert-markup
+               (if (muse-style-derived-p "html")
+                   (concat (if (not display) "<p>" "")
+			   "<img src=\"" path
+                           "\" alt=\"latex2png equation\" "
+                           (if display (concat "class=\"latex-inline\"")
+                             (concat "class=\"latex-display\""))
+                           (if (muse-style-derived-p "xhtml")
+                               " />"
+                             ">")
+                           (muse-insert-markup "<!-- " text "-->")
+			   (if (not display) "</p>" ""))
+                 (let ((ext (or (file-name-extension path) ""))
+                       (path (muse-path-sans-extension path)))
+                   (muse-markup-text 'image path ext))))
+              (goto-char (point-max)))
+            path))))))
+