class Peta.Root extends Peta.ElementNestableContent
  
  parts_element: () ->
    r = []
    _.each @my_class().child_models(), (k) =>
      l = @element_items(k)
      r = r.concat(l || [])
    r
  
  zorderd_elements: () ->
    res = []
    _.each @parts_element(), (e) =>
      res[e.get('z')-1] = e
    res
  
  scenario_elements: () ->
    res = []
    _.each @parts_element(), (e) =>
      res[e.get('t')] = e
    res