Goheeca/sdl2-cairo

Haskell library providing functions to use Cairo to draw on SDL textures and containing a Processing-style convenience drawing API.

sdl2-cairo

Haskell library providing functions to use Cairo to draw on SDL textures and containing a Processing-style convenience drawing API.

Install

This library depends on the new SDL2 bindings, available on Hackage as sdl2 version 2.0.0 or greater and cairo bindings.

Just clone and install this repository:

git clone git@github.com:apirogov/sdl2-cairo.git
cd sdl2-cairo
cabal install

It has been tested with GHC 7.10.1 on a Linux system without any problems.

Documentation

Generate the haddock documentation for reference.

You can use Cairo directly with the Render monad on an SDL texture like this:

import SDL.Cairo
import Graphics.Rendering.Cairo
...
  texture <- createCairoTexture renderer (V2 800 600)
  withCairoTexture texture $ do
    setSourceRGBA 1 0 0
    lineTo 800 600
    stroke

  copy renderer texture Nothing Nothing
  present renderer

If you are familiar with Processing, you can also use the simpler Canvas-API:

import SDL.Cairo
import SDL.Cairo.Canvas
...
  texture <- createCairoTexture renderer (V2 800 600)
  withCanvas texture $ do
    background $ gray 100
    stroke $ red 255
    fill $ blue 255 !@ 128
    rect $ D 0 0 100 100
    rect $ toD (V2 50 50) (V2 150 150)

  copy renderer texture Nothing Nothing
  present renderer

Finally, you can of course use this as glue to use diagrams with SDL with the Cairo backend:

import SDL.Cairo
import Diagrams.Backend.Cairo
...
  let (_,render) = renderDia Cairo (CairoOptions "" (mkSizeSpec $ V2 (Just 800) (Just 600))
                                                 RenderOnly False)
                                   (myDiagram :: QDiagram Cairo V2 Double Any)
  withCairoTexture texture render
...

See also the source of Main.hs for more examples. You start that demo with:

cabal run