module Graphics.Rendering.OpenGL.GL.VertexArrayObjects (
VertexArrayObject,
bindVertexArrayObject
) where
import Foreign.Marshal.Array
import Graphics.Rendering.OpenGL.GL.GLboolean
import Graphics.Rendering.OpenGL.GL.ObjectName
import Graphics.Rendering.OpenGL.GL.QueryUtils
import Graphics.Rendering.OpenGL.GL.StateVar
import Graphics.Rendering.OpenGL.Raw
newtype VertexArrayObject = VertexArrayObject { vertexArrayID :: GLuint }
deriving( Eq, Ord, Show )
instance ObjectName VertexArrayObject where
isObjectName = fmap unmarshalGLboolean . glIsVertexArray . vertexArrayID
deleteObjectNames bufferObjects =
withArrayLen (map vertexArrayID bufferObjects) $
glDeleteVertexArrays . fromIntegral
instance GeneratableObjectName VertexArrayObject where
genObjectNames n = allocaArray n $ \buf -> do
glGenVertexArrays (fromIntegral n) buf
fmap (map VertexArrayObject) $ peekArray n buf
bindVertexArrayObject :: StateVar (Maybe VertexArrayObject)
bindVertexArrayObject = makeStateVar getVAO bindVAO
getVAO :: IO (Maybe VertexArrayObject)
getVAO = do
vao <- getInteger1 (VertexArrayObject . fromIntegral) GetVertexArrayBinding
return $ if vao == noVAO then Nothing else Just vao
bindVAO :: Maybe VertexArrayObject -> IO ()
bindVAO = glBindVertexArray . vertexArrayID . maybe noVAO id
noVAO :: VertexArrayObject
noVAO = VertexArrayObject 0