-- #hide
--------------------------------------------------------------------------------
-- |
-- Module      :  Graphics.Rendering.OpenGL.GL.Texturing.TextureTarget
-- 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 is a purely internal module for marshaling texture targets.
--
--------------------------------------------------------------------------------

module Graphics.Rendering.OpenGL.GL.Texturing.TextureTarget (
   TextureTarget(..), marshalTextureTarget, marshalProxyTextureTarget,
   CubeMapTarget(..), marshalCubeMapTarget, unmarshalCubeMapTarget,
) where

import Graphics.Rendering.OpenGL.GL.PixelRectangles
import Graphics.Rendering.OpenGL.Raw.Core31

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

data TextureTarget =
     Texture1D
   | Texture2D
   | Texture3D
   | TextureCubeMap
   | TextureRectangle
   deriving ( Eq, Ord, Show )

marshalTextureTarget :: TextureTarget -> GLenum
marshalTextureTarget x = case x of
   Texture1D -> gl_TEXTURE_1D
   Texture2D -> gl_TEXTURE_2D
   Texture3D -> gl_TEXTURE_3D
   TextureCubeMap -> gl_TEXTURE_CUBE_MAP
   TextureRectangle -> gl_TEXTURE_RECTANGLE

marshalProxyTextureTarget :: Proxy -> TextureTarget -> GLenum
marshalProxyTextureTarget NoProxy x = marshalTextureTarget x
marshalProxyTextureTarget Proxy   x = case x of
   Texture1D -> gl_PROXY_TEXTURE_1D
   Texture2D -> gl_PROXY_TEXTURE_2D
   Texture3D -> gl_PROXY_TEXTURE_3D
   TextureCubeMap -> gl_PROXY_TEXTURE_CUBE_MAP
   TextureRectangle -> gl_PROXY_TEXTURE_RECTANGLE

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

data CubeMapTarget =
     TextureCubeMapPositiveX
   | TextureCubeMapNegativeX
   | TextureCubeMapPositiveY
   | TextureCubeMapNegativeY
   | TextureCubeMapPositiveZ
   | TextureCubeMapNegativeZ
   deriving ( Eq, Ord, Show )

marshalCubeMapTarget :: CubeMapTarget -> GLenum
marshalCubeMapTarget x = case x of
   TextureCubeMapPositiveX -> gl_TEXTURE_CUBE_MAP_POSITIVE_X
   TextureCubeMapNegativeX -> gl_TEXTURE_CUBE_MAP_NEGATIVE_X
   TextureCubeMapPositiveY -> gl_TEXTURE_CUBE_MAP_POSITIVE_Y
   TextureCubeMapNegativeY -> gl_TEXTURE_CUBE_MAP_NEGATIVE_Y
   TextureCubeMapPositiveZ -> gl_TEXTURE_CUBE_MAP_POSITIVE_Z
   TextureCubeMapNegativeZ -> gl_TEXTURE_CUBE_MAP_NEGATIVE_Z

unmarshalCubeMapTarget :: GLenum -> CubeMapTarget
unmarshalCubeMapTarget x
   | x == gl_TEXTURE_CUBE_MAP_POSITIVE_X = TextureCubeMapPositiveX
   | x == gl_TEXTURE_CUBE_MAP_NEGATIVE_X = TextureCubeMapNegativeX
   | x == gl_TEXTURE_CUBE_MAP_POSITIVE_Y = TextureCubeMapPositiveY
   | x == gl_TEXTURE_CUBE_MAP_NEGATIVE_Y = TextureCubeMapNegativeY
   | x == gl_TEXTURE_CUBE_MAP_POSITIVE_Z = TextureCubeMapPositiveZ
   | x == gl_TEXTURE_CUBE_MAP_NEGATIVE_Z = TextureCubeMapNegativeZ
   | otherwise = error $ "unmarshalCubeMapTarget: unknown enum " ++ show x