SFCGAL is a C++ wrapper library around CGAL with the aim of supporting
ISO 19107:2013 and OGC Simple Features Access 1.2 for 3D operations.
SFCGAL provides standard compliant geometry types and operations, that
can be accessed from its C or C++ APIs. PostGIS uses the C API, to
expose some SFCGAL's functions in spatial databases (cf. PostGIS
manual).
Geometry coordinates have an exact rational number representation and
can be either 2D or 3D.
