In fact i am asking for the method and the data needed for determining school catchment area.Example is http://www.qgso.qld.gov.au/maps/edmap/.
- Catchment boundary must not cross buildings and should follow transport network.
- There not be any un-allocated area (void) i.e. area is not under any catchment.
- I need some sort of automation at most extent.
Overview-- see below
When zoomed in a bit more-- see below
N.B. I think Example website related one can give elaborate answer.