import Graphics.Rendering.OpenGL
import Graphics.UI.GLUT
import Data.IORef

myPoints :: [(GLfloat,GLfloat,GLfloat)]
myPoints = map (\k -> (sin(2*pi*k/12),cos(2*pi*k/12),0.0)) [1..12]

main = do 
  (progname, _) <- getArgsAndInitialize
  --enterGameMode
  tme <- get elapsedTime
  lasttime <- newIORef(tme)
  state <- newIORef myPoints
  createWindow "Hello World"
  idleCallback $= Just (idle lasttime state)
  displayCallback $= (display state)
  mainLoop

display s = do 
  state<-readIORef s
  clear [ColorBuffer]
  renderPrimitive Triangles $ mapM_ (\(x, y, z)->vertex$Vertex3 x y z) state
  renderObject Solid (Cube 0.5)
  flush

idle lasttime state = do
   lTime <- readIORef lasttime
   currenttime <- get elapsedTime
   case (currenttime - lTime >= 16) of
         True -> do
            s<-readIORef state
            writeIORef state (map (\(x,y,z)->(x,y-0.01,z)) s)
            writeIORef lasttime currenttime
            postRedisplay Nothing
            return ()
         False -> return ()