[PATCH] ob-R.el, ox-latex.el: support for tikz graphics

[Aaron Ecay <aaronecay@gmail.com>]

Tikz graphics should be exported to LaTeX by \include, not as a link.
This commit changes the file extension used for tikz graphics from .tex
to .tikz.

TINYCHANGE
---
 lisp/ob-R.el     |  2 +-
 lisp/ox-latex.el | 22 +++++++++++++---------
 2 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/lisp/ob-R.el b/lisp/ob-R.el
index 8db0853..9875f81 100644
--- a/lisp/ob-R.el
+++ b/lisp/ob-R.el
@@ -237,7 +237,7 @@ current code buffer."
 	 '((:bmp . "bmp")
 	   (:jpg . "jpeg")
 	   (:jpeg . "jpeg")
-	   (:tex . "tikz")
+	   (:tikz . "tikz")
 	   (:tiff . "tiff")
 	   (:png . "png")
 	   (:svg . "svg")
diff --git a/lisp/ox-latex.el b/lisp/ox-latex.el
index 0ac251f..13da3f0 100644
--- a/lisp/ox-latex.el
+++ b/lisp/ox-latex.el
@@ -482,7 +482,7 @@ which format headlines like for Org version prior to 8.0."
   :type 'string)
 
 (defcustom org-latex-inline-image-rules
-  '(("file" . "\\.\\(pdf\\|jpeg\\|jpg\\|png\\|ps\\|eps\\)\\'"))
+  '(("file" . "\\.\\(pdf\\|jpeg\\|jpg\\|png\\|ps\\|eps\\|tikz\\)\\'"))
   "Rules characterizing image files that can be inlined into LaTeX.
 
 A rule consists in an association whose key is the type of link
@@ -1737,6 +1737,7 @@ used as a communication channel."
 	 (path (let ((raw-path (org-element-property :path link)))
 		 (if (not (file-name-absolute-p raw-path)) raw-path
 		   (expand-file-name raw-path))))
+	 (filetype (file-name-extension path))
 	 (caption (org-latex--caption/label-string parent info))
 	 ;; Retrieve latex attributes from the element around.
 	 (attr (org-export-read-attribute :attr_latex parent))
@@ -1764,22 +1765,25 @@ used as a communication channel."
 			  ((org-string-nw-p opt) (format "[%s]" opt))
 			  ((eq float 'float) "[width=0.7\\textwidth]")
 			  ((eq float 'wrap) "[width=0.48\\textwidth]")
-			  (t "")))))
+			  (t ""))))
+	 (image-code (if (equal filetype "tikz")
+			 (format "\\input{%s}" path)
+		       (format "\\includegraphics%s{%s}" options path))))
     ;; Return proper string, depending on FLOAT.
     (case float
       (wrap (format "\\begin{wrapfigure}%s
 \\centering
-%s\\includegraphics%s{%s}
-%s\\end{wrapfigure}" placement comment-include options path caption))
+%s%s
+%s\\end{wrapfigure}" placement comment-include image-code caption))
       (multicolumn (format "\\begin{figure*}%s
 \\centering
-%s\\includegraphics%s{%s}
-%s\\end{figure*}" placement comment-include options path caption))
+%s%s
+%s\\end{figure*}" placement comment-include image-code caption))
       (figure (format "\\begin{figure}%s
 \\centering
-%s\\includegraphics%s{%s}
-%s\\end{figure}" placement comment-include options path caption))
-      (t (format "\\includegraphics%s{%s}" options path)))))
+%s%s
+%s\\end{figure}" placement comment-include image-code caption))
+      (t image-code))))
 
 (defun org-latex-link (link desc info)
   "Transcode a LINK object from Org to LaTeX.
-- 
1.8.1.4