bind buffers before reading from them

src/Types/Graphics/IndexBuffer.hs

@@ -68,6 +68,7 @@ instance Buffer IndexBuffer where
             (fromIntegral currentBufSize `div`
               sizeOf (undefined :: StoreType IndexBuffer))
             $ \ (ptr :: Ptr (StoreType IndexBuffer)) -> do
+              bind buf
               GL.bufferSubData
                 (target buf)
                 GL.ReadFromBuffer

src/Types/Graphics/VertexBuffer.hs

@@ -98,6 +98,7 @@ instance Buffer VertexBuffer where
             (fromIntegral currentBufSize `div`
               sizeOf (undefined :: StoreType VertexBuffer))
             $ \ (ptr :: Ptr (StoreType VertexBuffer)) -> do
+              bind buf
               GL.bufferSubData
                 (target buf)
                 GL.ReadFromBuffer