CG_3DArea — Computes area of 3D surface geometries. Will return 0 for solids.
floatCG_3DArea(geometry geom1);
Availability: 3.5.0
This method needs SFCGAL backend.
This method implements the SQL/MM specification.
SQL-MM IEC 13249-3: 8.1, 10.5
This function supports 3d and will not drop the z-index.
This function supports Polyhedral surfaces.
This function supports Triangles and Triangulated Irregular Network Surfaces (TIN).
Note: By default a PolyhedralSurface built from WKT is a surface geometry, not solid. It therefore has surface area. Once converted to a solid, no area.
SELECT CG_3DArea(geom) As cube_surface_area, CG_3DArea(CG_MakeSolid(geom)) As solid_surface_area FROM (SELECT 'POLYHEDRALSURFACE( ((0 0 0,0 0 1,0 1 1,0 1 0,0 0 0)), ((0 0 0,0 1 0,1 1 0,1 0 0,0 0 0)), ((0 0 0,1 0 0,1 0 1,0 0 1,0 0 0)), ((1 1 0,1 1 1,1 0 1,1 0 0,1 1 0)), ((0 1 0,0 1 1,1 1 1,1 1 0,0 1 0)), ((0 0 1,1 0 1,1 1 1,0 1 1,0 0 1)) )'::geometry) As f(geom);
cube_surface_area │ solid_surface_area ──────────────────┼──────────────────── 6 │ 0