Opened 20 months ago
#5377 new enhancement
Proposal: ST_Node as a window function
| Reported by: | mdavis | Owned by: | pramsey |
|---|---|---|---|
| Priority: | low | Milestone: | PostGIS Fund Me |
| Component: | postgis | Version: | 3.3.x |
| Keywords: | Cc: |
Description
This proposes making a window function version of ST_Node (perhaps called ST_NodeWin. This will support the situation of noding a set of features together while preserving the attribution of each feature.
An example is noding a linear network, and preserving the attribute information for each network linear feature.
Note that unlike ST_Node this function will NOT dissolve identical linework (since each feature needs to have its full linework returned, possibly containing new nodes).
The function should support the optional gridSize argument as in other overlay functions. If gridSize is specified, the noding will use snap-rounding to provide precise and robust output.
There are two options for output: split and merged. Split output will split LineStrings into MultiLineStrings at each node. Merged will maintain LineStrings, but with vertices added at node points.
This will require a new GEOS function to support this functionality. See https://github.com/libgeos/geos/issues/877 for some discussion around this requirement.
