[PostGIS] #5859: Postgis Topology err Programmatic error ? Geometry of face 1098 is empty!

PostGIS trac at osgeo.org
Wed Mar 12 04:54:14 PDT 2025


#5859: Postgis Topology err Programmatic error ? Geometry of face 1098 is empty!
--------------------------------+---------------------------
  Reporter:  Lars Aksel Opsahl  |      Owner:  strk
      Type:  defect             |     Status:  new
  Priority:  medium             |  Milestone:  PostGIS 3.6.0
 Component:  topology           |    Version:  master
Resolution:                     |   Keywords:
--------------------------------+---------------------------
Comment (by strk):

 I guess edge 2 entered the topology AFTER edge 1 and thus missed to have
 edge 1 (pre-existing) SNAP to the very-close vertex of edge 2. This is the
 mother of all robustness bugs in PostGIS Topology. The experimental code
 handling edge merges now exists in the codebase but it is still only ever
 used when adding new NODES so this case doesn't trigger that code because
 no new node is considered to be needed by the preparation step.

 Maybe by using fixed-precision GEOS (available since GEOS-3.9) we'd get
 more nodes, this could be the road ahead...
-- 
Ticket URL: <https://trac.osgeo.org/postgis/ticket/5859#comment:5>
PostGIS <http://trac.osgeo.org/postgis/>
The PostGIS Trac is used for bug, enhancement & task tracking, a user and developer wiki, and a view into the subversion code repository of PostGIS project.


More information about the postgis-tickets mailing list