By Ether Data
Interactive publicationBack to Geo-Interop KB
Read the modelOpen the conversion explorer93 edge casesSearch

Unclosed rings

Geometry

A polygon ring whose first and last coordinates differ is not technically closed, causing GeoJSON-strict fillers to throw or silently miscompute area.

Detection

First coordinate does not equal last coordinate for any ring.

Mitigation

  • Auto-close by appending the first vertex
  • Reject upstream sources that produce unclosed rings and flag for a data-contract fix

Affected conversions

  • PolygonH3 (center-contained)
  • PolygonH3 (fully-contained)
  • PolygonH3 (intersects)