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Spatial Library

GEOS (Geometry Engine - Open Source) is a C++ port of the JTS Topology Suite (JTS). It includes the OpenGIS Simple Features for SQL spatial predicate functions and spatial operators, as well as specific JTS enhanced topology functions.

GEOS is the most widely used geospatial C++ geometry library, being used by open source projects such as PostGIS, QGIS, GDAL/OGR and MapServer, and by proprietary products including FME.

Implemented Standards

Core Features

  • Geometries: Point, LineString, Polygon, MultiPoint, MultiLineString, MultiPolygon, GeometryCollection
  • Predicates: Intersects, Touches, Disjoint, Crosses, Within, Contains, Overlaps, Equals, Covers
  • Operations: Union, Distance, Intersection, Symmetric Difference, Convex Hull, Envelope, Buffer, Simplify, Polygon Assembly, Valid, Area, Length,
  • Prepared geometries (pre-spatially indexed)
  • STR spatial index
  • OGC Well Known Text (WKT) and Well Known Binary (WKB) encoders and decoders.
  • C and C++ API (C API gives long term ABI stability)
  • Thread safe (using the reentrant API)



Licence: LGPL

Software Version: 3.5.1

Supported Platforms: Windows, Linux, Mac

API Interfaces: C, C++