cgal - ObjectVision/GeoDMS GitHub Wiki

The CGAL (Computational Geometry Algorithms Library) is a software library that provides easy access to efficient and reliable geometric algorithms. In the GeoDMS, CGAL is used alongside the geos, boost geometry and boost polygon libraries for geometric functions.

CGAL-based operators in the GeoDMS use exact predicates with exact constructions, providing robust and reliable results for geometric operations. This makes CGAL particularly well-suited for operations where numerical precision is critical.

when to use CGAL operators

CGAL operators are recommended when:

  • Maximum numerical precision is required
  • Complex polygon operations produce incorrect results with other libraries
  • Robustness is prioritized over speed

For most use cases, the geos-based operators are recommended as they offer the best balance of performance and reliability. CGAL operators may be slower but provide more mathematically exact results.

coordinate types

CGAL operators in the GeoDMS work with any point type (ipoint, spoint, fpoint, dpoint).

see also