[postgis-users] Topology and grade separation.

[Sandro Santilli]

On Wed, Jul 20, 2022 at 06:00:05PM +1000, Simon SPDBA Greener wrote:

> I could run up a quick test but does PostGIS topology have a mechanism for
> handling this situation? How does it handle linestrings defined as XYZ?

PostGIS Topology *forces* any planar intersection to generate a node.
There's no way to represent a river not intersecting a bridge over it.
Thee only handling of Z is to carry it around and interpolate it when
creating new intersections: it's a 2.5D topology.

What you describe may be better implemented with pgRouting.

--strk;