PostGIS topology ISO SQL/MM complete


PostGIS implementation of the ISO SQL/MM Topology-Geometry model is finally complete.

The SQL/MM model is just a portion of the whole topology support, but an important one, including schema definition and functions to create and populate the schema with primitive components (nodes, edges, faces).

In addition to the base model, PostGIS adds a TopoGeometry data type for use wherever you would normally use a Geometry type, except the former will be defined by references to primitive, shared, topological components.

The work on SQL/MM topology for PostGIS 2.0 was mainly funded by the Land Management department of the Tuscany Region as part of a larger project aimed at enhancing effectiveness of free software tools already in use within the institution for the management of the topographic database (chapeau!).

But more work is needed to make it easier to convert your layers to topological layers, your Geometries to TopoGeometries. Because I know you want to generalize your vectors in a topologically consistent way, don’t you ? And you want to edit the boundaries just once. And do you want to waste all that space for your triangles ?

Feature freeze for 2.0 will be by the end of November. Drop a note ASAP if you’d like to help with getting the enhanced TopoGeometry constructor shipped with it.