[GRASS-dev] r51975, vlib: improve PostGIS topology support, introduce level 3

[Martin Landa]

Hi Markus,

2012/6/6 Markus Metz <markus.metz.giswork at googlemail.com>:

first of all, thanks for the quick review!

> I find the newly introduced level 3 for topology confusing because 1)
> level 3 could sometime in the future mean 3D topology, 2) level 3
> applies only to PostGIS. Before that change, the open level had the
> same meaning independent of the vector format (GRASS, PGR, PostGIS).

right.

> The open level is important for modules, and for modules it does not
> matter if topology is pseudo-topology or PostGIS topology or true
> GRASS topology. Modules only check if topology is available or not,
> but are and should not be interested in what kind of topology is
> available. This should be handled by the vector libs. I would

Sounds reasonable to me.

> therefore prefer to keep the two open levels and rather have a flag in
> struct Format_info_pg indicating whether this map is opened with
> pseudo-topology or PostGIS topology.

It's already there (pg_info->toposchema_name).

I was worried about introducing level 3 in this sense, you just made
me sure, that it was not a good idea. I will revert it back to the two
levels (keep level 3 for 3D topology).

Martin

-- 
Martin Landa <landa.martin gmail.com> * http://geo.fsv.cvut.cz/~landa