GetFaceByPoint
Name
GetFaceByPoint — Finds face intersecting a given point.
Synopsis
integer
GetFaceByPoint
(
varchar
atopology
, geometry
apoint
, float8
tol1
)
;
Description
Finds a face referenced by a Point, with given tolerance.
The function will effectively look for a face intersecting a circle having the point as center and the tolerance as radius.
If no face intersects the given query location, 0 is returned (universal face).
If more than one face intersect the query location an exception is thrown.
Availability: 2.0.0
Enhanced: 3.2.0 more efficient implementation and clearer contract, stops working with invalid topologies.
Examples
SELECT topology.GetFaceByPoint('ma_topo',geom, 10) As with1mtol, topology.GetFaceByPoint('ma_topo',geom,0) As withnotol
FROM ST_GeomFromEWKT('POINT(234604.6 899382.0)') As geom;
with1mtol | withnotol
-----------+-----------
1 | 0
SELECT topology.GetFaceByPoint('ma_topo',geom, 1) As nearnode
FROM ST_GeomFromEWKT('POINT(227591.9 893900.4)') As geom;
-- get error --
ERROR: Two or more faces found