H2GIS

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ST_3DArea

Signature

DOUBLE ST_Area(GEOMETRY geom);

Description

Compute the 3D area of a polygon or a multipolygon derived from a 3D triangular decomposition. In the case of a 2D Geometry, ST_3DArea returns the same value as ST_Area.

Area is measured in the units of the spatial reference system.

Examples

SELECT ST_3DArea('POLYGON((0 0 3, 10 0 4, 10 10 6, 0 10 2, 0 0 3))');
-- Answer: 105.27

SELECT ST_3DArea('POLYGON((0 0, 10 0, 10 10, 0 10, 0 0))');
-- Answer: 100.0

SELECT ST_Area('MULTIPOLYGON(((0 0 3, 10 0 4, 10 10 6, 0 10 2, 0 0 3),
                              (5 4 1, 1 1 2, 3 4 3, 4 5 2, 5 4 1)))');
-- Answer: 111.88

SELECT ST_Area('GEOMETRYCOLLECTION(
                  LINESTRING(5 4, 1 1, 3 4, 4 5),
                  POINT(0 12),
                  POLYGON((0 0, 10 0, 10 10, 0 10, 0 0)),
                  POLYGON((5 4, 1 1, 3 4, 4 5, 5 4)))');
-- Answer: XXXX

SELECT ST_3DArea('LINESTRING(5 4, 1 1, 3 4, 4 5)');
-- Answer: 0.0
See also