Constructs an sfmesh object from the well-known text (WKT) representation of an sfmesh.
Syntax
sfmesh ST_MeshFromText(text wkt);
sfmesh ST_MeshFromText(text wkt, int4 srid);Parameters
| Parameter | Type | Description |
|---|---|---|
wkt | text | The sfmesh object in WKT representation. |
srid | int4 | The spatial reference identifier (SRID) to embed in the returned sfmesh. |
Return type
sfmesh
Usage notes
Without `srid`: Returns an sfmesh with no embedded spatial reference identifier.
With `srid`: Embeds the specified SRID in the returned sfmesh as part of its metadata.
Examples
The following example constructs an sfmesh from a WKT string with SRID 4490 and returns it in EWKT format.
SELECT ST_AsEWKT(ST_MeshFromText('{"version" : 1, "root" : 0, "meshgeoms" : ["MESHGEOM(PATCH(TRIANGLESTRIP(0 0,0 10,10 10,10 0)))"], "primitives" : [{"meshgeom" : 0}], "nodes" : [{"primitive" : 0}]}', 4490));Expected output:
{"version" : 1, "srid" : 4490, "root" : 0, "meshgeoms" : ["MESHGEOM(PATCH(TRIANGLESTRIP(0 0,0 10,10 10,10 0)))"], "primitives" : [{"meshgeom" : 0}], "nodes" : [{"primitive" : 0}]}Notice that srid appears in the output when specified. Omit the second argument to construct an sfmesh without an embedded SRID.
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