geos: Geos (Geometry Engine - Open Source)
geos:
geos: Geos is a C++  port of the Java  Topology Suite (JTS). As such, it
geos: aims  to  contain  the  complete functionality of JTS in C++. This
geos: includes  all  the  OpenGIS  "Simple  Features  for  SQL"  spatial
geos: predicate functions and spatial operators, as well as specific JTS
geos: topology functions such as IsValid().
geos:
geos:
geos:
geos: