PostGIS
Description
Returns true if the 3D distance between two geometry values is no larger
than distance distance_of_srid. The distance is specified in units
defined by the spatial reference system of the geometries. For this
function to make sense the source geometries must be in the same
coordinate system (have the same SRID).
|
This function
supports 3d and will not drop the z-index.
This function
supports Polyhedral surfaces.
This method
implements the SQL/MM specification. SQL-MM ?
Availability: 2.0.0
Examples
-- Geometry example - units in meters (SRID: 2163 US National Atlas Equal area) (3D point and line compared 2D point and line)
-- Note: currently no vertical datum support so Z is not transformed and assumed to be same units as final.
SELECT ST_3DDWithin(
ST_Transform(ST_GeomFromEWKT('SRID=4326;POINT(-72.1235 42.3521 4)'),2163),
ST_Transform(ST_GeomFromEWKT('SRID=4326;LINESTRING(-72.1260 42.45 15, -72.123 42.1546 20)'),2163),
126.8
) As within_dist_3d,
ST_DWithin(
ST_Transform(ST_GeomFromEWKT('SRID=4326;POINT(-72.1235 42.3521 4)'),2163),
ST_Transform(ST_GeomFromEWKT('SRID=4326;LINESTRING(-72.1260 42.45 15, -72.123 42.1546 20)'),2163),
126.8
) As within_dist_2d;
within_dist_3d | within_dist_2d
----------------+----------------
f | tSee Also
ST_3DDFullyWithin, ST_DWithin, ST_DFullyWithin, ST_3DDistance, ST_Distance, ST_3DMaxDistance, ST_Transform
ST_Within |
ST_3DDFullyWithin |