Announcing diagrams 0.5

I am pleased to announce the release of version 0.5 of diagrams, a full-featured framework and embedded domain-specific language for declarative drawing. Check out the gallery for examples of what it can do!

Highlights of this release include:

• A new diagrams-contrib package of user-contributed modules, which so far contains code for tree drawing, Apollonian gaskets, planar tilings, "wrapped" layout, and turtle graphics.
• Experimental support for animation, built on top of the new active library.
• Numerous small additions and improvements, including more general rounded rectangle shapes and better text support.
• Much better performance in some common situations, such as laying out a very long list of diagrams using ‘cat’ and related combinators.
• Added support for GHC 7.4.

See the release notes for complete details, and the diagrams wiki for help migrating code from 0.4 to 0.5 (changes should be minimal).

Try it out

For the truly impatient:

cabal install gtk2hs-buildtools
cabal install diagrams

Diagrams is supported under GHC 6.12, 7.0, 7.2, and 7.4. However, getting cairo to build can be tricky on some platforms; see the diagrams wiki for more information and workarounds regarding specific platforms. (A new native SVG backend is in the works, targeted for the 0.6 release.)

To get started with diagrams, read the quick tutorial, which will introduce you to the fundamentals of the framework.

For those who are even less impatient but want to really dig in and use the power features, read the user manual.

Get involved

Subscribe to the project mailing list, and/or come hang out in the #diagrams IRC channel on freenode.org for help and discussion. Make some diagrams. Fix some bugs. Submit your cool examples for inclusion in the gallery or your cool code for inclusion in the diagrams-contrib package!

Happy diagramming!

Brought to you by the diagrams team:

• Peter Hall
• Ian Ross
• Michael Sloan
• Ryan Yates
• Brent Yorgey

with contributions from:

• Sam Griffin
• Claude Heiland-Allen
• John Lato
• Vilhelm Sjöberg
• Luite Stegeman
• Kanchalai Suveepattananont
• Scott Walck

Announcing diagrams-0.4

I am pleased to announce the release of version 0.4 of diagrams, a full-featured framework and embedded domain-specific language for declarative drawing.

The last announcement was of the 0.1 release; there have been quite a few changes and improvements since then, including:

• A new website including a gallery of examples
• A new comprehensive user manual with lots of illustrative examples
• New primitive shapes: rounded rectangles, wedges, and a new flexible API for generating polygons
• Cubic splines
• Basic text support
• Support for external image primitives
• Lots more convenient combinators, bug fixes, and improvements

Cool, how can I try it out?

For the truly impatient:

cabal install gtk2hs-buildtools
cabal install diagrams

For the slightly less impatient, read the quick tutorial, which has detailed information about how to install the necessary packages and will introduce you to the fundamentals of the framework.

For those who are even less impatient but want to really dig in and use the power features, read the user manual.

Cool, how can I contribute?

There are lots of ways you can contribute! First, you may want to subscribe to the project mailing list, and/or come hang out in the #diagrams IRC channel on freenode.org.

• There are lots of easy bug fixes, improvements, and feature requests just waiting for people wanting to get involved: see the bug tracker for a list of open tickets.

  The source repositories are mirrored using both darcs (on patch-tag.com) and git (on github.com), and patches are accepted in either place, thanks to Owen Stephen’s great work on darcs-bridge.

• Create a higher-level module built on top of the diagrams framework (e.g. tree or graph layout, generating Turing machine configuration diagrams, Penrose tilings … your imagination is the only limit!) and submit it for inclusion in a special diagrams-contrib package which will be created for such higher-level user-contributed modules.
• Use diagrams to create some cool graphics and submit them for inclusion in the gallery.
• Start your own project built on top of diagrams and let us know how it goes!
• Last but certainly not least, just try it out for your pet graphics generation needs and contribute your bug reports and feature requests.

Happy diagramming!

Brought to you by the diagrams team:

• Brent Yorgey
• Ryan Yates

with contributions from:

• Sam Griffin
• Claude Heiland-Allen
• John Lato
• Vilhelm Sjöberg
• Luite Stegeman
• Kanchalai Suveepattananont
• Scott Walck

Announcing diagrams preview release

I am extremely pleased to announce a "developer preview" release of the diagrams framework for declarative drawing. This is a well-thought-out, well-documented, working release with all core functionality in place, but with many planned features still missing (for example, support for rendering text and higher-level tools for constructing curves). If you are interested in

• trying out a new way of producing vector graphics,
• providing feedback to help drive ongoing development, or
• getting involved and contributing some code yourself,

please give it a try! On the other hand, if you are looking for a complete, full-featured package that will let you jump right into producing the graphics you need, you may want to wait for the 1.0 release.

If you are familiar with the diagrams package already on Hackage, this is a complete rewrite which has been in the works for over a year and a half.

What is it?

Diagrams is an embedded domain-specific library (EDSL) for creating diagrams, illustrations, and other sorts of vector graphics. The overall vision is for diagrams to become a viable alternative to systems like MetaPost, Asymptote, and PGF/TikZ.

Diagrams is:

• Declarative: you specify what a diagram is, not how to draw it.

• Compositional: diagrams can be combined in many ways to produce more complex diagrams. Diagrams are scale- and translation-invariant, so you never have to worry about a "global" coordinate system, only "local" ones.

• Embedded: the full power of Haskell, including every library on Hackage, is available to help construct and manipulate diagrams.

• Extensible: extending diagrams with additional or higher-level functionality is as simple as writing a Haskell module.

• Flexible: diagrams is designed from the ground up to be as generic and flexible as possible. Features include:

  • Pluggable rendering backends — creating a new rendering backend is as simple as writing a type class instance.

  • Arbitrary vector spaces — the core diagrams library data types and primitives work for any vector space, so given a suitable rendering backend you can produce diagrams of any dimension, or even more exotic things…

Cool, how can I try it out?

Start by reading the quick tutorial, which has detailed information about how to install the necessary packages and will introduce you to the fundamentals of the framework.

Or, for the truly impatient:

cabal install diagrams-core diagrams-lib diagrams-cairo

How can I contribute?

There are lots of ways you can contribute! First, you may want to subscribe to the project mailing list, and/or come hang out in the #diagrams IRC channel on freenode.org.

• Cairo is the only well-supported backend at the moment, but you might create another backend or contribute to an existing project.

• The standard library is in need of additional features. Visit the Google Code site for a list of open tickets.

• Create a higher-level module built on top of the diagrams framework (e.g. tree or graph layout, generating Turing machine configuration diagrams, Penrose tilings … your imagination is the only limit!) and submit it for inclusion in a special diagrams-contrib package which will be created for such higher-level user-contributed modules.

• Use diagrams to create some cool graphics and submit them for inclusion in a gallery of examples (to be created soon).

• Start your own project built on top of diagrams and let us know how it goes!

• Last but certainly not least, just try it out for your pet graphics generation needs and contribute your bug reports and feature requests.

Happy diagramming!

Brought to you by the diagrams team:

• Brent Yorgey
• Ryan Yates

with contributions from:

• Sam Griffin
• Vilhelm Sjöberg
• Luite Stegeman
• Kanchalai Suveepattananont
• Scott Walck

Diagrams 0.2 release

After meaning to get around to it for quite a while, I’ve finally released version 0.2 of the Haskell diagrams library. Here’s the release announcement. And here’s one of my favorite examples showing off the new path support:

Heighway dragon

I made this Heighway dragon curve in just a few minutes of hacking this afternoon, with the following code:

{- Heighway dragon.  See http://en.wikipedia.org/wiki/Dragon_curve. -}
module Main where

import Graphics.Rendering.Diagrams
import Control.Monad.State
import Data.Maybe

dragonStr :: Int -> String
dragonStr 0 = "FX"
dragonStr n = concatMap rules $ dragonStr (n-1)
  where rules 'X' = "X+YF+"
        rules 'Y' = "-FX-Y"
        rules c = [c]

strToPath :: String -> Path
strToPath s = pathFromVectors . catMaybes $ evalState c (0,-1)
  where c        = mapM exec s
        exec 'F' = Just `fmap` get
        exec '-' = modify left >> return Nothing
        exec '+' = modify right >> return Nothing
        exec _   = return Nothing
        left (x,y)  = (-y,x)
        right (x,y) = (y,-x)

dragon :: Int -> Diagram
dragon = lc red . curved 0.8 . strToPath . dragonStr

main = renderAs PNG "dragon.png" (Width 300) (dragon 12)

A special thank you to Dougal Stanton for adding text rendering support and other features, switching diagrams over to Russell O’Connor’s colour library, and generally helping out with this release.