Schedule - FOSDEM PGDay 2013

3D an exact geometries for PostGIS

Date: 2013-02-01
Time: 14:30–15:20
Room: Radisson Blu
Level: Intermediate

PostGIS 2.0 brings extended support for the third dimension. Geometry types are able to carry a z coordinate and new types have been added for triangulated and polyhedral surfaces.

We are currently going a bit further with respect to 3D by adding support for 3D spatial operations (intersection and intersection test, 3D convex hull, 3D extrusion, etc.) to PostGIS, with the objective to support ISO 19107 and OGC Simple Features for SQL 3D operations.

This is done through the use of the powerful CGAL C++ library which also exhibits very good performances (even when used for 2D operations).

CGAL also brings the ability to compute geometrical operations without loss of precision, using a geometry representation based on arbitrary precision numbers.

This talk will focus on the new 3D geometry types and operations added in this prototype. Some benchmark results on 2D operations will be shown regarding performance comparison with the current implementation. It will also explain how the exact computation model has been taken into account into PostgreSQL (creation of a new type, issues with serialization and with the memory management policy).


Hugo Mercier