+++ Braden Shepherdson [Jan 31 09 18:23 ]:
Brent Yorgey wrote:
I am very pleased to announce the 0.2 release of the diagrams package, an embedded domain-specific language for creating simple graphics in a compositional style. This release includes a number of significant new features, including:
* support for arbitrary straight and curved paths * more shape primitives, including polygons and rounded rectangles * support for rendering text * PNG, PDF, PS, and SVG output * built-in color support replaced with external dependence on the feature-rich colour library
and many more! More information, examples, and installation instructions can be found at http://code.haskell.org/diagrams. More features are planned for future releases, so contributions and suggestions are welcome.
(Please note: since diagrams depends on the Cairo library, which has unfortunately not been Cabalized, you cannot install the diagrams library with cabal-install, unless you already have the cairo package installed. See the above website for instructions.)
A special thanks to Dougal Stanton for his contributions to the library and help in preparing this release.
-Brent
Would this make a handy plugin for gitit? I'm currently putting diagrams together in xfig and saving them to my gitit tree while taking notes in gitit, but being able to write diagrams code into gitit would be great.
How easy or hard would this be to accomplish?
Not too hard, I think. Here's code for something similar (for graphviz diagrams), derived from plugins/DotPlugin.hs in SVN pandoc. transform :: Block -> IO Block transform (CodeBlock (id, classes, namevals) contents) | "dot" `elem` classes = do let (name, outfile) = case lookup "name" namevals of Just fn -> ([Str fn], fn ++ ".png") Nothing -> ([], uniqueName contents ++ ".png") result <- readProcess "dot" ["-Tpng"] contents writeFile outfile result return $ Para [Image name (outfile, "")] transform x = return x -- | Generate a unique filename given the file's contents. uniqueName :: String -> String uniqueName = showDigest . sha1 . fromString The 'transform' function will transform delimited code blocks such as ~~~ {.dot name="diagram1"} digraph G {Hello->World} ~~~ into images generated by running the contents through graphviz's dot. To lift this into a transformation of Pandoc documents, you can use syb: convertGraphviz :: Pandoc -> IO Pandoc convertGraphviz = everywhereM (mkM transform) With minimal modifications, the same technique should work for diagrams... Best, John