    --------------------------------------------------------------------------------
    -- |
    -- Module      :  Graphics.Rendering.OpenGL.GLU.Initialization
    -- Copyright   :  (c) Sven Panne 2002-2009
    -- License     :  BSD-style (see the file libraries/OpenGL/LICENSE)
    --
    -- Maintainer  :  sven.panne@aedion.de
    -- Stability   :  stable
    -- Portability :  portable
    --
    -- This module corresponds to chapter 2 (Initialization) of the GLU specs.
    --
    --------------------------------------------------------------------------------

    module Graphics.Rendering.OpenGL.GLU.Initialization (
       gluVersion, gluExtensions
    ) where

    import Data.StateVar
    import Foreign.C.String
    import Foreign.Ptr
    import Graphics.Rendering.GLU.Raw
    import Graphics.Rendering.OpenGL.GL.QueryUtils
    import Graphics.Rendering.OpenGL.Raw.Core31

    --------------------------------------------------------------------------------

    gluVersion :: GettableStateVar String
    gluVersion = makeGettableStateVar (getString glu_VERSION)

    gluExtensions :: GettableStateVar [String]
    gluExtensions = makeGettableStateVar (fmap words $ getString glu_EXTENSIONS)

    getString :: GLenum -> IO String
    getString n = gluGetString n >>=
                  maybeNullPtr (return "") (peekCString . castPtr)