Fix demo dependencies

README.md

@@ -0,0 +1,7 @@
+Combinators for drawing 2D shapes and images in Haskell (using OpenGL)
+
+* Summary: this module is a functional wrapper around OpenGL, so you don't have to go into the deep, dark world of imperative stateful programming just to draw stuff. It supports 2D only (for now), with support drawing geometry, images, and text.
+
+* [Online documentation](http://hackage.haskell.org/package/graphics-drawingcombinators-1.4.4.1/docs/Graphics-DrawingCombinators.html)
+
+* [Hackage entry](http://hackage.haskell.org/package/graphics-drawingcombinators)

demo/example_b.hs

@@ -0,0 +1,63 @@
+import Control.Monad
+import Data.Monoid
+import Graphics.DrawingCombinators ((%%))
+import qualified Graphics.DrawingCombinators             as Draw
+import qualified Graphics.UI.GLFW                        as GLFW
+import Data.IORef
+import Data.Maybe
+
+import System.Environment(getArgs)
+
+windowWidth, windowHeight :: Int
+windowWidth = 800
+windowHeight = 600
+
+initGL :: IO GLFW.Window
+initGL = do
+    isInited <- GLFW.init
+    unless isInited $ error "Cannot init GLFW"
+
+    maybeW <- GLFW.createWindow windowWidth windowHeight "DrawingCombinators demo" Nothing Nothing
+    let window = fromMaybe (error "No window was created") maybeW
+    GLFW.makeContextCurrent $ Just window
+
+    return window
+
+unitText :: Draw.Font -> String -> Draw.Image Any
+unitText font str = (Draw.translate (-1,0) %% Draw.scale (2/w) (2/w) %% Draw.text font str)
+                        `mappend`
+                    Draw.tint (Draw.Color 1 0 0 1) (Draw.line (-1,0) (1,0))
+    where
+    w = Draw.textWidth font str
+
+quadrants :: (Monoid a) => Draw.Image a -> Draw.Image a
+quadrants img = mconcat [
+    (Draw.translate (-0.5,0.5) %%),
+    (Draw.translate (0.5,0.5)   `Draw.compose` Draw.rotate (-pi/2) %%),
+    (Draw.translate (0.5,-0.5)  `Draw.compose` Draw.rotate pi %%),
+    (Draw.translate (-0.5,-0.5) `Draw.compose` Draw.rotate (pi/2) %%)] (Draw.scale 0.5 0.5 %% img)
+
+circleText :: Draw.Font -> String -> Draw.Image Any
+circleText font str = unitText font str `mappend` Draw.tint (Draw.Color 0 0 1 0.5) Draw.circle
+
+main :: IO ()
+main = do
+    args <- getArgs
+    font <- case args of
+        [fontName] -> Draw.openFont fontName
+        _          -> error "Usage: drawingcombinators-example some_font.ttf"
+
+    window <- initGL
+
+    done <- newIORef False
+    GLFW.setWindowCloseCallback window (Just $ const $ writeIORef done True)
+    mainLoop window font done 0.0
+
+    where
+        mainLoop window font done rotation = do
+            Draw.clearRender $ Draw.rotate rotation %% quadrants (circleText font "Hello, world!")
+            GLFW.swapBuffers window
+            GLFW.pollEvents
+            doneValue <- readIORef done
+            when (not doneValue) $
+                mainLoop window font done (rotation - 0.01)

graphics-drawingcombinators.cabal

@@ -13,7 +13,7 @@ Author: Luke Palmer
 Homepage: http://github.com/luqui/graphics-drawingcombinators
 Maintainer: [email protected]
 Build-Type: Simple
-Extra-Source-Files: demo/example.hs
+Extra-Source-Files: demo/example.hs, demo/example-b.hs
 cabal-Version: >= 1.8
 
 source-repository head
@@ -47,5 +47,15 @@ Executable example
   else
     Buildable:     True
     Build-depends: base >= 3 && < 5,
-                   GLFW-b, OpenGL >= 2.2 && < 2.7, graphics-drawingcombinators
+                   GLFW, OpenGL >= 2.2 && < 2.9, graphics-drawingcombinators
+    ghc-options:   -Wall
+
+Executable example_b
+  Main-is:       demo/example_b.hs
+  if !flag(examples)
+    Buildable:     False
+  else
+    Buildable:     True
+    Build-depends: base >= 3 && < 5,
+                   GLFW-b >= 1.4, OpenGL >= 2.2 && < 2.9, graphics-drawingcombinators
     ghc-options:   -Wall