-- | Computes the group of an instance per the primary node.
instancePriGroup :: Node.List -> Instance.Instance -> Gdx
instancePriGroup nl i =
  let pnode = Container.find (Instance.pNode i) nl
  in  Node.group pnode
instancePriGroup :: Node.List -> Instance.Instance -> Gdx
instancePriGroup nl i =
  let pnode = Container.find (Instance.pNode i) nl
  in  Node.group pnode
instancePriGroup nl i =
  let pnode = Container.find (Instance.pNode i) nl
  in  Node.group pnode